RNA polymerase variants for co-transcriptional capping

Abstract

The present disclosure provides RNA polymerase variants for high efficiency transcription.

Description

RELATED APPLICATIONS This application claims the benefit under 35 U.S.C. § 119(e) of U.S. provisional application number 62 / 808,182, filed February 20, 2019, U.S. provisional application number 62 / 832,314, filed April 11, 2019, and U.S. provisional application number 62 / 885,928, filed August 13, 2019, each of which is incorporated by reference herein in its entirety. BACKGROUND In vitro transcription (IVT) uses bacteriophage DNA-dependent ribonucleic acid (RNA) polymerases (e.g., SP6, T3 and T7) to synthesize template-directed mRNA transcripts. Problems in the IVT reaction can result in complete failure (e.g., no transcript generated) or in transcripts that are the incorrect size (e.g., shorter or longer than expected). Specific problems associated with IVT reactions include, for example, abortive (truncated) transcripts, run-on transcripts, polyA tail variants / 3' heterogeneity, mutated transcripts, and / or double-stranded contaminants produced during the reactions. RNA polymerases exhibit three phases of transcription - initiation, elongation and termination. During the initiation phase, the RNA polymerase binds to a specific promoter DNA sequence, opens the DNA duplex and feeds the template strand into the active site. T7 RNA polymerase, for example, forms a structure referred to as initiation complex, which includes a six-helix bundle sub-domain (the promoter binding domain) that interacts with the promoter to initiate DNA duplex melting. While bound to the promoter, the polymerase produces many short (truncated) transcripts from 2-12 nucleotides (nt) in length, a process often referred to as abortive synthesis / initiation. The truncated RNA transcripts cannot be converted to full-length transcripts by RNA polymerase and become by-products that accumulate during transcription. After the transition to the elongation phase and release of the promoter, the polymerase proceeds down the DNA template producing a full-length RNA transcript. During the elongation phase, RNA polymerase often continues to transcribe DNA beyond the point at which termination should be initiated, generating longer than expected RNA transcripts (“run-on transcripts”). T7 RNA polymerase, for example, adds nucleotides to the end of a transcript before ‘falling off’ the template. Studies suggest that more than 70% of transcripts generated by T7 RNA polymerase in vitro may be run-on transcripts. In some cases, these aberrant RNA products are twice the length of the encoded sequence. Because run-on transcription is stochastic, there is often great 3' heterogeneity among products in a given IVT reaction. This 3' heterogeneity is problematic for downstream applications, such as ligation reactions, which are dependent on RNA transcripts of a defined length and / or nucleotide composition. SUMMARY Provided herein, in some aspects, are RNA polymerase variants and in vitro transcription methods using these variants. The RNA polymerase variants of the present disclosure have been shown, in some embodiments, that when used in an in vitro transcription reaction, for example, the polymerase variants, increase transcription efficiency, increase co-transcriptional capping efficiency, increase yield of RNA and improve 3’ homogeneity of RNA at half the concentration of a cap analog, improve fidelity of transcription, and / or lower the amount of dsRNA contamination. Some aspects of the present disclosure provide a ribonucleic acid (RNA) polymerase variant comprising a RNA polymerase that comprises at least one amino acid substitution. In some embodiments, the RNA polymerase variant comprises a RNA polymerase that comprises at least one amino acid substitution at a position selected from the group consisting of E350, D351, K387, N437, K441, D506, R632, D653, S628, P657, F88O, and G884 relative to a RNA polymerase comprising the amino acid sequence of SEQ ID NO: 44. In some embodiments, the RNA polymerase variant comprises a RNA polymerase that comprises amino acid substitutions at two of the positions selected from the group consisting of E350, D351, K387, and D653, relative to a wild-type RNA polymerase comprising the amino acid sequence of SEQ ID NO: 1. In some embodiments, the two amino acid substiutions are E350 and D351. In some embodiments, the two amino acid substiutions are E350 and K387. In some embodiments, the two amino acid substiutions are K387 and D653. In some embodiments, the RNA polymerase comprises an amino acid substitution at E350. In some embodiments, the RNA polymerase comprises an amino acid substitution at D351. In some embodiments, the RNA polymerase comprises an amino acid substitution at K387. In some embodiments, the RNA polymerase comprises an amino acid substitution at N437. In some embodiments, the RNA polymerase comprises an amino acid substitution at K441. In some embodiments, the RNA polymerase comprises an amino acid substitution at D506. In some embodiments, the RNA polymerase comprises an amino acid substitution at R632. In some embodiments, the RNA polymerase comprises an amino acid substitution at D653. In some embodiments, the RNA polymerase comprises an amino acid substitution at S628. In some embodiments, the RNA polymerase comprises an amino acid substitution at P657. In some embodiments, the RNA polymerase comprises an amino acid substitution at F88O. In some embodiments, the RNA polymerase comprises an amino acid substitution at G884. In some embodiments, the RNA polymerase comprises at least two, at least three, at least four, or at least five amino acid substitutions at positions selected from the group consisting of E350, D351, K387, N437, K441, D506, R632, D653, S628, P657, F88O, and G884. In some embodiments, the RNA polymerase comprises amino acid substitutions at positions selected from the group consisting of: E350 and D351; E350 and K387; E350 and N437; E350 and K441; E350 and D506; E350 and R632; E350 and D653; E350 and S628; E350 and P657; E350 and F88O; E350 and G884; D351 and K387, D351 and N437; D351 and K441; D351 and D506; D351 and R632; D351 and D653; D351 and S628; D351 and P657; D351 and F88O; D351 and G884; K387 and N437; K387 and K441; K387 and D506; K387 and R632; K387 and D653; K387 and S628; K387 and P657; K387 and F88O; and K387 and G884; N437 and K441; N437 and D506; N437 and R632; N437 and D653; N437 and S628; N437 and P657; N437 and F88O; N437 and G884; K441 and D506; K441 and R632; K441 and D653; K441 and S628; K441 and P657; K441 and F88O; K441 and G884; D506 and R632; D506 and D653; D506 and S628; D506 and P657; D506 and F880; D506 and G884; R632 and D653; R632 and S628; R632 and P657; R632 and F88O; R632 and G884; D653 and S628; D653 and P657; D653 and F880; D653 and G884; S628 and P657; S628 and F88O; S628 and G884; P657 and F880; P657 and G884; and F88O and G884. In some embodiments, the RNA polymerase comprises acid substitutions at positions selected from the group consisting of: K387, D653, and G884; E350, D351, and K387; and D653, P657, and R632. In some embodiments, the amino acid substitution at E350 is selected from the group consisting of E350A, E350K, E350N, and E35OW, optionally wherein the amino acid substitution at E350 is E350N. In some embodiments, the amino acid substitution at D351 is D351V. In some embodiments, the amino acid substitution at K387 is selected from the group consisting of K387H, K387N, and K387S, optionally wherein the amino acid substitution at K387 is K387N. In some embodiments, the amino acid substitution at N437 is selected from the group consisting of N437F, N437I, N437T, and N437Y, optionally wherein the amino acid substitution at N437 is N437F. In some embodiments, the amino acid substitution at K441 is K441R. In some embodiments, the amino acid substitution at D506 is selected from the group consisting of D506F, D506L, D506R, D506W, and D506Y. In some embodiments, the amino acid substitution at R632 is R632K or R632T. In some embodiments, the amino acid substitution at D653 is selected from the group consisting of D653A, D653F, D653G, D653H, D653I, D653K, D653L, D653M, D653N, D653P, D653Q, D653R, D653S, D653T, D653V, D653W, and D653Y, optionally wherein the amino acid substitution at D653 is D653W. In some embodiments, the amino acid substitution at S628 is S628W. In some embodiments, the amino acid substitution at P657 is selected from the group consisting of P657A, P657R, and P657W. In some embodiments, the amino acid substitution at F88O is F88OY. In some embodiments, the amino acid substitution at G884 is selected from the group consisting of G884A, G884S, G884T, and G884P. In some embodiments, the RNA polymerase comprises a sequence of any one of claims 61-241. Other aspects of the present disclosure provide a method comprising producing a mRNA in an in vitro transcription reaction that comprises a DNA template, nucleoside triphosphates, any one of the RNA polymerase variants as described herein, and optionally a cap analog. In some embodiments, the reaction comprises the cap analog. In some embodiments, the reaction comprises a concentration of the cap analog that is at least 5-fold lower than a concentration of the cap analog required to produce an equivalent amount of mRNA using a T7 RNA polymerase that comprises the amino acid sequence of SEQ ID NO: 44. In some embodiments, greater than 80% of the mRNA produced includes a functional cap, greater the 50% of the mRNA produced is homogeneous at the 3’ end, and / or the reaction comprises less than 5 ng dsRNA per 25 pg of mRNA produced. In some embodiments, the cap analog and nucleoside triphosphates are present in the reaction at equimolar concentrations, or a molar ratio of cap analog to nucleoside triphosphates in the reaction is greater than 1:1. In some embodiments, the cap analog is a dinucleotide cap, a trinucleotide cap, or a tetranucleotide cap. In some embodiments, the cap analog is a trinucleotide cap analog comprising a GAG sequence. In some embodiments, the GAG cap analog comprises a compound selected from: In some embodiments, the cap analog is a tetranucleotide cap analog comprising a GGAG sequence. In some embodiments, the tetranucleotide cap analog comprises a compound selected from: In some embodiments, the polynucleotide template includes a 2'-deoxythymidine residue or a 2'-deoxycytidine residue at template position +1. Other aspects of the present disclosure provide a composition or kit comprising any one of the RNA polymerase variants as described herein and an IVT reaction component, optionally selected from the group consisting of a polynucleotide template, nucleoside triphosphates, and a cap analog. Other aspects of the present disclosure provide a nucleic acid encoding any one of the RNA polymerase variants as described herein. BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A-1H show graphs depicting the functional characteristics of transcribed RNA products resulting from in vitro transcription (IVT) reactions involving mutant variants of a control T7 RNA polymerase variant (G47A+C-terminal G) in the presence of varying levels of GAG cap analog. Following an oligo dT purification, transcribed RNA products were analyzed for yield (FIG. 1A), 3’ homogeneity (FIG. IB), amount of dsRNA (FIG. IC), percent capped RNA (FIG. ID and FIG. IE), purity according to a DBAA (dibutylammonium acetate) HPLC method (FIG. IF), percent tailed (i.e., percent of RNA comprising a polyA tail) according to a Tris RP (reverse-phase) method (FIG. 1G), and indel frequency (FIG. 1H). FIGS. 2A-2C show graphs depicting the percent capped RNA resulting from in vitro transcription (IVT) reactions involving mutant variants of a control T7 RNA polymerase variant (G47A+C-terminal G) in the presence of varying levels of GGG cap (FIG. 2A), m6A cap (FIG. 2B), and e6A cap (FIG. 2C). FIGS. 3A-3E show graphs depicting the functional characteristics of transcribed RNA products resulting from in vitro transcription (IVT) reactions involving mutant variants of a control T7 RNA polymerase variant (G47A+C-terminal G) in the presence of varying levels of GAG cap analog. Following an oligo dT purification, transcribed RNA products were analyzed for concentration (FIG. 3A), percent tailed (i.e., percent of RNA comprising a polyA tail) according to a Tris RP (reverse-phase) method (FIG. 3B), purity according to a DBAA (dibutylammonium acetate) HPLC method (FIG. 3C), 3’ homogeneity (FIG. 3D), and amount of dsRNA (FIG. 3E). FIGS. 4A-4E show graphs depicting the percent capped RNA resulting from in vitro transcription (IVT) reactions involving mutant variants of a control T7 RNA polymerase variant (G47A+C-terminal G) in the presence of varying levels of GAG cap. FIGS. 5A-5D show graphs depicting the percent capped RNA resulting from IVT reactions involving mutant variants of a control T7 RNA polymerase variant (G47A+C-terminal G) in the presence of varying levels of e6A trinucleotide (trinuc). FIGS. 6A-6D show graphs depicting the percent capped RNA resulting from IVT reactions involving mutant variants of a control T7 RNA polymerase variant (G47A+C-terminal G) in the presence of varying levels of m6A trinuc. FIG. 7 shows a graph depicting the percent capped RNA resulting from IVT reactions involving mutant variants of a control T7 RNA polymerase variant (G47A+C-terminal G) in the presence of varying levels of a GGAG tetranucleotide (tetranuc). The structure of the GGAG tetranucleotide is provided in the lower half of FIG. 7. FIGs. 8A-8I show graphs depicting the percent capped RNA (FIGs. 8A-8D) and relative RNA yield (FIG. 8E-8I) resulting from IVT reactions involving mutant variants of a control T7 RNA polymerase variant (G47A+C-terminal G) in the presence of a GAG trinuc, m6A trinuc, e6A trinuc, or tetranuc. FIGs. 8E-8I are normalized to an IVT reaction involving WT T7 RNA polymerase. FIGs. 9A-9D show graphs depicting dsRNA content resulting from IVT reactions involving mutant variants of a control T7 RNA polymerase in the presence of GAG trinuc (FIG. 9A), m6A trinuc (FIG. 9B), e6A trinuc (FIG. 9C), and GGAG tetranuc (FIG. 9D). FIGs. 10A-10D show graphs depicting the 3’ homogeneity (FIG. 10A), percent capped RNA (FIG. 10B), percent full-length RNA product (FIG. IOC), and crude yield over time (FIG. 10D) resulting from IVT reactions involving mutant variants of a control T7 RNA polymerase in the presence of a GAG trinuc. FIG. 11 shows a graph depicting the percent capped RNA resulting from IVT reactions involving the D653W+G47A RNA polymerase variant in the presence of varying concentrations of cap analogs. FIG. 12 shows a graph depicting the capping efficiency of multi-substitution RNA polymerase variants in the presence of a GAG trinucleotide cap analog. FIGs. 13A-13B show graphs depicting the relative RNA yield (FIG. 13A) and percent capped RNA (FIG. 13B) resulting from IVT reactions involving multi-substitution RNA polymerase variants in the presence of GGAG tetranucleotide cap analog. FIGS. 14A-14E show graphs depicting the functional characteristics of transcribed RNA products resulting from IVT reactions involving multi-substitution RNA polymerase variants and three different DNA templates in the presence of GGAG tetranucleotide cap analog. Following an oligo dT purification, transcribed RNA products were analyzed for percent capped RNA (FIG. 14A), percent tailed RNA (i.e., percent of RNA comprising a polyA tail) according to a Tris RP (reverse-phase) method (FIG. 14B), purity according to a RP HPLC method (FIG. 14C), 3’ homogeneity (FIG. 14D), and amount of dsRNA (FIG. 14E). FIGs. 15A-15E show graphs depicting the functional characteristics of transcribed RNA products resulting from IVT reactions involving multi-substitution RNA polymerase variants in the presence of GGAG tetranucleotide cap analog. Following an oligo dT purification, transcribed RNA products were analyzed for yield of RNA (FIG. 15A), percent capped RNA (FIG. 15B), amount of dsRNA (FIG. 15C), purity according to a RP HPLC method (FIG. 15D), and percent tailed RNA (i.e., percent of RNA comprising a polyA tail) (FIG. 15E). DETAILED DESCRIPTION RNA polymerase (DNA-dependent RNA polymerase) is an enzyme that catalyzes the sequential addition of a ribonucleotide to the 3' end of a growing RNA chain (transcription of RNA in the 5' —> 3' direction), with nucleoside triphosphates (NTPs) acting as substrates for the enzyme and with the sequence of nucleotides specified by a DNA template. Transcription relies on the complementary pairing of bases. The two strands of a double helix separate locally, and one of the separated strands serves as a template (DNA template). RNA polymerase then catalyzes the alignment of free nucleotides on the DNA template by their complementary bases in the template. Thus, a RNA polymerase is considered to have RNA polymerase activity if the polymerase catalyzes the sequential addition of a ribonucleotide to the 3' end of a growing RNA chain. DNA-directed RNA polymerases are capable of initiating synthesis of RNA without primers; the first catalytic stage of initiation is referred to as de novo RNA synthesis. De novo synthesis is a unique phase in the transcription cycle where the RNA polymerase binds two nucleotides rather than a nascent RNA polymer and a single nucleotide. For bacteriophage T7 RNA polymerase, transcription begins with a marked preference for GTP at the +1 and +2 positions. Initiating nucleotides bind RNA polymerase in locations distinct from those described for elongation complexes (Kennedy WP et al. J Mol Biol. 2007; 370(2): 256-68). Selection bias in favor of GTP as an initiating nucleotide is achieved by shape complementarity, extensive protein side-chain, and strong base-stacking interactions for the guanine moiety in the enzyme active site. Thus, an initiating GTP provides the largest stabilization force for the open promoter conformation (Kennedy et al. 2007). The RNA polymerase variants of the present disclosure, in some embodiments, comprise one or more amino acid substitution(s) at one or more binding site residue(s) for de novo RNA synthesis, which, without being bound by theory, alters RNA polymerase affinity to the cap analog of an in vitro transcription reaction, for example, such that there is an improvement in capping efficiency at low cap analog concentrations. Thus, the present disclosure, in some aspects, provides RNA polymerase variants that comprises a RNA polymerase that includes an amino acid substitution at a binding site residue for de novo RNA synthesis. A RNA polymerase variant is an enzyme having RNA polymerase activity and at least one substitution and / or modification relative to the counterpart wild-type RNA polymerase. In some embodiments, the amino acid substitution at a binding site residue is a substitution at a position selected from positions 350, 351, 387, 394, 425, 427, 437, 441, 506, 628, 632, 653, 657, 811, and 880, relative to the wild-type RNA polymerase, wherein the wildtype RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at a binding site residue is a substitution at a position selected from positions 350, 351, 387, 394, 437, 441, 506, 628, 632, 653, and 657, relative to the wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. Structural studies of T7 RNA polymerase have shown that the conformation of the N-terminal domain changes substantially between the initiation phase and elongation phase of transcription. The N-terminal domain comprises a C-helix subdomain and the promoter binding domain, which includes two segments separated by subdomain H. The promoter binding domain and the bound promoter rotate by approximately 45 degrees upon synthesis of an 8-nt RNA transcript, allowing the promoter contacts to be maintained while the active site is expanded to accommodate a growing heteroduplex. The C-helix subdomain moves modestly toward its elongation conformation, whereas subdomain H remains in its initiation- rather than its elongation-phase location, more than 70 angstroms away. Comparison of the structures of the T7 RNA polymerase initiation and elongation complexes reveal extensive conformational changes within the N-terminal 267 residues (N-terminal domain) and little change in the rest of the RNA polymerase. A rigid body rotation of the promoter binding domain as well as the refolding of the N-terminal C-helix (residues 28-71) and H (residues 151-190) subdomains are responsible for abolishing the promoter binding site, enlarging the active site and creating an exit tunnel for the RNA transcript. In particular, residues E42-G47 of T7 RNA polymerase, which exist as a P-loop structure in the initiation complex, adopt an a-helical structure in the elongation complex. The structural changes within the N-terminal domain account for the increased stability and the processivity of the elongation complex (see, e.g., Dumiak, K.J. et al., Science 322(5901): 553557, 2008, incorporated herein by reference). Provided herein, in some aspects, are RNA polymerase variants (e.g., T7 RNA polymerase variants) that facilitate the conformational change from the RNA polymerase initiation complex to the RNA polymerase elongation complex. In some embodiments, a RNA polymerase variant comprises at least one amino acid modification, relative to wild-type RNA polymerase, that causes at least one three-dimensional loop structure of the RNA polymerase variant to undergo a conformational change to a helix structure as the RNA polymerase variant transitions from an initiation complex to an elongation complex. Thus, in some embodiments, at least one amino acid modification has a high-helix propensity, relative to wild-type amino acid. In some embodiments, a RNA polymerase variant comprises an amino acid substitution at one or more of positions 42, 43, 44, 45, 46, and 47, relative to the wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 47 is G47A. Examples of loop structures include but are not limited to amino acid (aa) 42-47 in the C-helix structure (e.g., aa 28-71 of SEQ ID NO:1) of the T7 RNA polymerase initiation complex (IC) conformation and aa 257-262 in the C-linker structure (e.g., aa 258-266 of SEQ ID NO:1) of the IC. Thus, some aspects of the present disclosure provide RNA polymerase variants that comprise multiple amino acid substitutions and / or modifications, relative to wild-type RNA polymerase. In some embodiments, a RNA polymerase variant comprise a RNA polymerase that includes (a) an amino acid substitution at a binding site residue for de novo RNA synthesis, and (b) an amino acid substitution that facilitates the conformational change from the RNA polymerase initiation complex to the RNA polymerase elongation complex. Further, the RNA polymerase variants provided herein, in some embodiments, includes an amino acid modification comprising at least one additional amino acid at the C terminus of the polymerase. The at least one additional amino acid, in some embodiments, is selected from alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine. In some embodiments, the at least one additional amino acid is a polar amino acid. In some embodiments, the at least one additional amino acid is a non-polar amino acid. In some embodiments, the at least one additional amino acid is glycine. In some embodiments, the at least one additional amino acid is alanine. In some embodiments, the at least one additional amino acid is serine. Use of the RNA polymerase variants of the present disclosure, for example, in an in vitro transcription reaction, in some embodiments, increases transcription efficiency, relative to a control RNA polymerase. For example, use of a RNA polymerase variant may increase the transcription efficiency (e.g., RNA yield and / or rate of transcription) by at least 20%. In some embodiments, use of a RNA polymerase variant increases the transcription efficiency (e.g., RNA yield and / or rate of transcription) by at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 10%. In some embodiments, use of a RNA polymerase variant increases the transcription efficiency by 20-100%, 20-90%, 20-80%, 20-70%, 20-60%, 20-50%, 30-100%, 30-90%, 30-80%, 30-70%, 30-60%, 30-50%, 40-100%, 40-90%, 40-80%, 40-70%, 40-60%, 40-50%, 50-100%, 50-90%, 50-80%, 50-70%, or 50-60%. In some embodiments, use of a RNA polymerase variant increases the total RNA yield by at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 10%. In some embodiments, use of a RNA polymerase variant increases the total RNA yield by 20100%, 20-90%, 20-80%, 20-70%, 20-60%, 20-50%, 30-100%, 30-90%, 30-80%, 30-70%, 3060%, 30-50%, 40-100%, 40-90%, 40-80%, 40-70%, 40-60%, 40-50%, 50-100%, 50-90%, 5080%, 50-70%, or 50-60%. In some embodiments, use of a RNA polymerase variant increases the rate of transcription by at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 10%. In some embodiments, use of a RNA polymerase variant increases the rate of transcription by 20-100%, 20-90%, 20-80%, 20-70%, 20-60%, 20-50%, 30100%, 30-90%, 30-80%, 30-70%, 30-60%, 30-50%, 40-100%, 40-90%, 40-80%, 40-70%, 4060%, 40-50%, 50-100%, 50-90%, 50-80%, 50-70%, or 50-60%. In some embodiments, the control RNA polymerase is a wild-type RNA polymerase comprising the amino acid sequence of SEQ ID NO: 1 (“wild-type T7 RNA polymerase”). In other embodiments, the control RNA polymerase is a RNA polymerase variant comprising an amino acid sequence of SEQ ID NO: 1 modified to include G47A substitution and an additional glycine at its C-terminus (“control T7 RNA polymerase variant” or “G47A+C-terminal G T7 RNA polymerase variant” or “control RNA polymerase variant” or “G47A+C-terminal G RNA polymerase variant”). Surprisingly, the data provided herein show that use of the RNA polymerase variants of the present disclosure in an in vitro transcription reaction enable the use of a much lower concentration (amount) of cap analog to produce an amount of capped RNA equivalent to that produced using the wild-type T7 RNA polymerase or the control RNA polymerase variant. In some embodiments, use of the RNA polymerase variants of the present disclosure, for example, in an in vitro transcription reaction increases the yield of capped RNA when half the concentration of a cap analog use in the in vitro transcription reaction. In some embodiments, use of the RNA polymerase variants of the present disclosure, for example, in an in vitro transcription reaction increases the yield of capped RNA when only 25%, 50%, or 75% of the concentration of a cap analog is use in the in vitro transcription reaction. For example, use of a RNA polymerase variant may increase the yield of capped RNA by at least 20%, when only 25%, 50%, or 75% of the concentration of a cap analog is use in the in vitro transcription reaction. In some embodiments, use of a RNA polymerase variant increases the yield of capped RNA by at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 100%, when only 25%, 50%, or 75% of the concentration of a cap analog is use in the in vitro transcription reaction. In some embodiments, use of a RNA polymerase variant increases the yield of capped RNA by 20-100%, 20-90%, 20-80%, 20-70%, 20-60%, 20-50%, 30-100%, 30-90%, 30-80%, 30-70%, 30-60%, 30-50%, 40-100%, 40-90%, 40-80%, 40-70%, 40-60%, 40-50%, 50-100%, 50-90%, 50-80%, 50-70%, or 50-60%, when only 25%, 50%, or 75% of the concentration of a cap analog is use in the in vitro transcription reaction. In some embodiments, the control RNA polymerase is a wild-type T7 RNA polymerase. In other embodiments, the control RNA polymerase is a control RNA polymerase variant. In some embodiments, use of a RNA polymerase variant increases the total yield of capped RNA by at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 10%. In some embodiments, use of a RNA polymerase variant increases the total yield of capped RNA by 20-100%, 20-90%, 20-80%, 20-70%, 20-60%, 20-50%, 30100%, 30-90%, 30-80%, 30-70%, 30-60%, 30-50%, 40-100%, 40-90%, 40-80%, 40-70%, 4060%, 40-50%, 50-100%, 50-90%, 50-80%, 50-70%, or 50-60%. In some embodiments, use of the RNA polymerase variants of the present disclosure, for example, in an in vitro transcription reaction increases the co-transcriptional capping efficiency. For example, use of a RNA polymerase variant may increase the co-transcriptional capping efficiency (e.g., percentage of transcript comprising cap analog) by at least 20%. In some embodiments, use of a RNA polymerase variant increases the co-transcriptional capping efficiency (e.g., percentage of transcript comprising cap analog) by at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 100%. In some embodiments, use of a RNA polymerase variant increases the co-transcriptional capping efficiency by 20-100%, 20-90%, 20-80%, 20-70%, 20-60%, 20-50%, 30-100%, 30-90%, 3080%, 30-70%, 30-60%, 30-50%, 40-100%, 40-90%, 40-80%, 40-70%, 40-60%, 40-50%, 50100%, 50-90%, 50-80%, 50-70%, or 50-60%. In some embodiments, the control RNA polymerase is a wild-type T7 RNA polymerase. In other embodiments, the control RNA polymerase is a control RNA polymerase variant. In some embodiments, at least 50% of the mRNA comprises a functional cap analog. For example, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 95%, or 100% of the mRNA may comprise a cap analog. In some embodiments, 50%-100%, 50%-90%, 50%-80%, or 50%-70% of the mRNA comprises a cap analog. In some embodiments, use of the RNA polymerase variants of the present disclosure, for example, in an in vitro transcription reaction improves 3’ homogeneity of RNA at half the concentration of a cap analog use in the in vitro transcription reaction. For example, use of a RNA polymerase variant may improve 3’ homogeneity of RNA by at least 20%, when only 25%, 50%, or 75% of the concentration of a cap analog is use in the in vitro transcription reaction. In some embodiments, use of a RNA polymerase variant improves 3’ homogeneity by at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 100%, when only 25%, 50%, or 75% of the concentration of a cap analog is use in the in vitro transcription reaction. In some embodiments, use of a RNA polymerase variant improves 3’ homogeneity by 20-100%, 20-90%, 20-80%, 20-70%, 20-60%, 20-50%, 30-100%, 30-90%, 3080%, 30-70%, 30-60%, 30-50%, 40-100%, 40-90%, 40-80%, 40-70%, 40-60%, 40-50%, 50100%, 50-90%, 50-80%, 50-70%, or 50-60%, when only 25%, 50%, or 75% of the concentration of a cap analog is use in the in vitro transcription reaction. In some embodiments, the control RNA polymerase is a wild-type T7 RNA polymerase. In other embodiments, the control RNA polymerase is a control RNA polymerase variant. In some embodiments, at least 50% of the mRNA produced in an in vitro transcription reaction that comprises a RNA polymerase variant of the present disclosure exhibits 3’ homogeneity. For example, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 95%, or 100% of the mRNA exhibits 3’ homogeneity. In some embodiments, 50%-100%, 50%-90%, 50%-80%, or 50%-70% of the mRNA exhibits 3’ homogeneity. In some embodiments, the mRNA produced in an in vitro transcription reaction that comprises a RNA polymerase variant of the present disclosure has greater than a threshold 3’ homogeneity. In some embodiments, the threshold is 50% or at least 50%. For example, the threshold may be 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90%. In some embodiments, use of the RNA polymerase variants of the present disclosure, for example, in an in vitro transcription reaction improves fidelity (e.g., mutation rate) of transcription. For example, use of a RNA polymerase variant may improve fidelity of transcription by at least 20%. In some embodiments, use of a RNA polymerase variant improves fidelity of transcription by at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 100%. In some embodiments, use of a RNA polymerase variant improves fidelity of transcription by 20-100%, 20-90%, 20-80%, 20-70%, 20-60%, 2050%, 30-100%, 30-90%, 30-80%, 30-70%, 30-60%, 30-50%, 40-100%, 40-90%, 40-80%, 4070%, 40-60%, 40-50%, 50-100%, 50-90%, 50-80%, 50-70%, or 50-60%. A RNA polymerase variant of the present disclosure that improves fidelity of transcription will produce RNA transcript (e.g., mRNA transcript) with a lower rate or total number of mutations than a control RNA polymerase. In some embodiments, the control RNA polymerase is a wild-type T7 RNA polymerase. In other embodiments, the control RNA polymerase is a control RNA polymerase variant. In some embodiments, the mRNA produced using a RNA polymerase variant of the present disclosure has less than 1 mutation per 100 nucleotides relative to the DNA template. For example, the mRNA produced may have less than 1 mutation per 200, 300, 400, 500, 600, 700, 800, 900 or 1000 nucleotides relative to the DNA template. In some embodiments, use of the RNA polymerase variants of the present disclosure, for example, in an in vitro transcription reaction lowers the amount of double-stranded RNA (dsRNA) contamination in the in vitro transcription reaction. For example, use of a RNA polymerase variant may lower the amount of dsRNA contamination in the in vitro transcription reaction by at least 20%. In some embodiments, use of a RNA polymerase variant lowers the amount of dsRNA contamination in the in vitro transcription reaction by at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 100%. In some embodiments, use of a RNA polymerase variant lowers the amount of dsRNA contamination in the in vitro transcription reaction by 20-100%, 20-90%, 20-80%, 20-70%, 2060%, 20-50%, 30-100%, 30-90%, 30-80%, 30-70%, 30-60%, 30-50%, 40-100%, 40-90%, 4080%, 40-70%, 40-60%, 40-50%, 50-100%, 50-90%, 50-80%, 50-70%, or 50-60%. In some embodiments, the control RNA polymerase is a wild-type T7 RNA polymerase. In other embodiments, the control RNA polymerase is a control RNA polymerase variant. In some embodiments, the concentration of dsRNA contamination is less than 10 ng per 25 pig of mRNA product. In some embodiments, the concentration of dsRNA contamination is less than 5 ng per 25 pig of mRNA product. For example, the concentration of dsRNA contamination may be less than 4 ng per 25 pig of mRNA product, less than 3 ng per 25 pig of mRNA product, less than 2 ng per 25 pig of mRNA product, or less than less than 1 ng per 25 pig of mRNA product. In some embodiments, the concentration of dsRNA contamination is 0.5-1, 0.5-2, 0.5-3, 0-.4, or 0.5-5 ng per 25 pig of mRNA product. In some embodiments, the mRNA produced in an in vitro transcription reaction that comprises a RNA polymerase variant of the present disclosure has lower than a threshold quantity of dsRNA. In some embodiments, the threshold is 10 ng. In some embodiments, the threshold is 5 ng. In some embodiments, the threshold is 4 ng, 3 nm, 2 ng, or 1 ng. Amino Acid Substitutions and Modifications RNA polymerase variants of the present disclosure include at least one amino acid substitution, relative to the wild type (WT) RNA polymerase. For example, with reference to WT T7 RNA polymerase having an amino acid sequence of SEQ ID NO: 1, the glycine at position 47 is considered a “wild-type amino acid,” whereas a substitution of the glycine for alanine at position 47 is considered an “amino acid substitution” that has a high-helix propensity. In some embodiments, the RNA polymerase variant is a T7 RNA polymerase variant comprising at least one (one or more) amino acid substitution relative to WT RNA polymerase (e.g., WT T7 RNA polymerase having an amino acid sequence of SEQ ID NO:1). In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an (at least one) amino acid modification causes a loop structure of the RNA polymerase variant to undergo a conformational change to a helix structure as the RNA polymerase variant transitions from an initiation complex to an elongation complex. In some embodiments, the amino acid modification is an amino acid substitution at one or more of positions 42, 43, 44, 45, 46, and 47, relative to the wild-type RNA polymerase, wherein the wildtype RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. The amino acid substitution, in some embodiments, is a high propensity amino acid substitution. Examples of high-helix propensity amino acids include alanine, isoleucine, leucine, arginine, methionine, lysine, glutamine, and / or glutamate. In some embodiments, the amino acid substitution at position 47 is G47A. In some embodiments, a RNA polymerase variant comprise a RNA polymerase that includes an additional C-terminal amino acid, relative to the wild-type RNA polymerase. The additional C-terminal amino acid, in some embodiments, is selected from glycine, alanine, threonine, proline, glutamine, and serine. In some embodiments, the additional C-terminal amino acid (e.g., at position 884 relative to wild-type RNA polymerase comprising the amino acid sequence of SEQ ID NO: 1) is glycine. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an (at least one) amino acid modification at a position that is not a conserved amino acid residue. Conserved amino acid residues are amino acids or amino acid types (e.g., individual amino acids such as Gly or Ser, or groups of amino acids that share similar properties such as amino acids with acidic functional groups) that are generally shared across multiple homologous sequences of the same protein. Conserved amino acid residues can be identified using sequence alignments of homologous amino acid sequences. A sequence alignment of approximately 1000 RNA polymerase sequences obtained using a Basic Local Alignment search allowed for a determination of the 240 positions of SEQ ID NO: 1 that are most likely to be conserved across RNA polymerase sequences. These 240 positions of SEQ ID NO: 1 that are most likely to be conserved across RNA polymerase sequences are at positions 5-6, 39, 269-277, 279, 281-282, 323-333, 411-448, 454-470, 472-474, 497-516, 532-560, 562-573, 626-646, 691, 693-702, 724738, 775-794, 805-820, 828-833, 865-867, and 877-879. Accordingly, in some embodiments, a RNA polymerase variant of the present disclosure comprises a RNA polymerase that includes an (at least one) amino acid modification at a position that is not one of positions 5-6, 39, 269-277, 279, 281-282, 323-333, 411-448, 454-470, 472-474, 497-516, 532-560, 562-573, 626-646, 691, 693-702, 724-738, 775-794, 805-820, 828-833, 865-867, and 877-879 of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant as described herein may further comprise any number of amino acid modifications at any number of positions that are not one of positions 5-6, 39, 269277, 279, 281-282, 323-333, 411-448, 454-470, 472-474, 497-516, 532-560, 562-573, 626-646, 691, 693-702, 724-738, 775-794, 805-820, 828-833, 865-867, and 877-879 of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprising a RNA polymerase of any one of SEQ ID NO: 2-247 may further comprise an (at least one) additional amino acid modification at a position that is not one of positions 5-6, 39, 269-277, 279, 281-282, 323-333, 411-448, 454470, 472-474, 497-516, 532-560, 562-573, 626-646, 691, 693-702, 724-738, 775-794, 805-820, 828-833, 865-867, and 877-879. Conversely, the amino acid positions that are not conserved are most likely to be modified or mutated. Accordingly, in some embodiments, a RNA polymerase variant of the present disclosure comprises a RNA polymerase that includes an (at least one) amino acid modification at positions 1-4, 7-38, 40-268, 278, 280, 283-322, 334-410, 449-453, 471, 475-496, 517-531, 561, 574-625, 647-690, 692, 703-723, 739-774, 795-804, 821-827, 834864, 868-876, and 880-883. In some embodiments, a RNA polymerase variant comprising a RNA polymerase of any one of SEQ ID NO: 2-247 may further comprise an (at least one) additional amino acid modification at positions 1-4, 7-38, 40-268, 278, 280, 283-322, 334-410, 449-453, 471, 475-496, 517-531, 561, 574-625, 647-690, 692, 703-723, 739-774, 795-804, 821827, 834-864, 868-876, and 880-883. In some embodiments, a RNA polymerase variant comprising a RNA polymerase of any one of SEQ ID NO: 2-247 may further comprise an (at least one) amino acid modification at any amino acid position that does not disrupt the secondary or tertiary structure of the RNA polymerase protein. In some embodiments, a RNA polymerase variant comprising a RNA polymerase of any one of SEQ ID NO: 2-247 may further comprise an (at least one) amino acid modification at any amino acid position that does not disrupt the ability of the RNA polymerase protein to fold. In some embodiments, a RNA polymerase variant comprising a RNA polymerase of any one of SEQ ID NO: 2-247 may further comprise an (at least one) amino acid modification at any amino acid position that does not disrupt the ability of the RNA polymerase protein to bind to nucleic acids (e.g., DNA). In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes (a) an amino acid substitution at aposition selected from positions 350, 351, 387, 394, 425, 427, 437, 441, 506, 628, 632, 653, 657, 811, and 880, and (b) an additional amino acid substitution and / or an amino acid modification at the C-terminal end, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes (a) an amino acid substitution at aposition selected from positions 350, 351, 387, 394, 437, 441, 506, 628, 632, 653, and 657, and (b) an additional amino acid substitution and / or an amino acid modification at the C-terminal end, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 350, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a lysine (K) at position 350 (E350K), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an asparagine (N) at position 350 (E350N), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an alanine (A) at position 350 (E350A), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a tryptophan at position 350 (E350W), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 351, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a valine (V) at position 351 (D351V), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 387, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a serine at position 387 (K387S), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a histidine (H) at position 387 (K387H), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an asparagine at position 387 (K387N), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wildtype RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 394, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 425, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 427, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 437, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a threonine at position 437 (N437T), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an isoleucine at position 437 (N437I), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a tyrosine at position 437 (N437Y), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a phenylalanine at position 437 (N437F), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 441, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an arginine at position 441 (K441R), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 506, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a tryptophan (W) at position 506 (D506W), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wildtype RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 506 is D506A, D506R, D506N, D506C, D506E, D506Q, D506G, D506H, D506I, D506L, D506K, D506M, D506F, D506P, D506S, D506T, D506W, D506Y, or D506V. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 628, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a tryptophan (W) at position 628 (S628W), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wildtype RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 628 is S628A, S628R, S628N, S628D, S628C, S628E, S628Q, S628G, S628H, S628I, S628L, S628K, S628M, S628F, S628P, S628T, S628W, S628Y, or S628V. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 632, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 653, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a tryptophan (W) at position 653 (D563W), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wildtype RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 653 is D653A, D653R, D653N, D653C, D653E, D653Q, D653G, D653H, D653I, D653L, D653K, D653M, D653F, D653P, D653S, D653T, D653W, D653Y, or D653V. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 657, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a tryptophan (W) at position 657 (P657W), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wildtype RNA polymerase comprises the amino acid sequence of SEQ ID NO: l.In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 811, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 657 is P657A, P657R, P657N, P657D, P657C, P657E, P657Q, P657G, P657H, P657I, P657L, P657K, P657M, P657F, P657S, P657T, P657W, P657Y, or P657V. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), an amino acid substitution at position 880, and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), a tyrosine at position 880 (F88OY), and / or an additional amino acid (e.g., G) at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes an amino acid substitution at position 47 (e.g., G47A), and an additional amino acid at the C-terminal end (at position 884), relative to wild-type RNA polymerase, wherein the wildtype RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the additional amino acid at the C-terminal end is threonine (T). In some embodiments, the additional amino acid at the C-terminal end is serine (S). In some embodiments, the additional amino acid at the C-terminal end is alanine (A). In some embodiments, the additional amino acid at the C-terminal end is proline (P). In some embodiments, a RNA polymerase variant comprises a RNA polymerase that comprises an amino acid substitution at position 350, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 350 is selected from the group consisting of E350R, E350K, E350H, E350D, E350Q, E350N, E350T, E350S, E350C, E350G, E350A, E350V, E350I, E350M, E350P, E350Y, E350W, and E350F. In some embodiments, the amino acid substitution at position 350 is E350R. In some embodiments, the amino acid substitution at position 350 is E350K. In some embodiments, the amino acid substitution at position 350 is E350H. In some embodiments, the amino acid substitution at position 350 is E350D. In some embodiments, the amino acid substitution at position 350 is E350Q. In some embodiments, the amino acid substitution at position 350 is E350N. In some embodiments, the amino acid substitution at position 350 is E350T. In some embodiments, the amino acid substitution at position 350 is E350S. In some embodiments, the amino acid substitution at position 350 is E350C. In some embodiments, the amino acid substitution at position 350 is E350G. In some embodiments, the amino acid substitution at position 350 is E350A. In some embodiments, the amino acid substitution at position 350 is E350V. In some embodiments, the amino acid substitution at position 350 is E350I. In some embodiments, the amino acid substitution at position 350 is E350M. In some embodiments, the amino acid substitution at position 350 is E350P. In some embodiments, the amino acid substitution at position 350 is E350Y. In some embodiments, the amino acid substitution at position 350 is E350W. In some embodiments, the amino acid substitution at position 350 is E350F. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that comprises an amino acid substitution at position 351, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 351 is selected from the group consisting of D351R, D351K, D351H, D351E, D351Q, D351N, D351T, D351S, D351C, D351G, D351A, D351V, D351I, D351M, D351P, D351Y, D351W, and D351F. In some embodiments, the amino acid substitution at position 351 is D351R. In some embodiments, the amino acid substitution at position 351 is D351K. In some embodiments, the amino acid substitution at position 351 is D351H. In some embodiments, the amino acid substitution at position 351 is D351E. In some embodiments, the amino acid substitution at position 351 is D351Q. In some embodiments, the amino acid substitution at position 351 is D351N. In some embodiments, the amino acid substitution at position 351 is D351T. In some embodiments, the amino acid substitution at position 351 is D351S. In some embodiments, the amino acid substitution at position 351 is D351C. In some embodiments, the amino acid substitution at position 351 is D351G. In some embodiments, the amino acid substitution at position 351 is D351A. In some embodiments, the amino acid substitution at position 351 is D351V. In some embodiments, the amino acid substitution at position 351 is D351I. In some embodiments, the amino acid substitution at position 351 is D351M. In some embodiments, the amino acid substitution at position 351 is D351P. In some embodiments, the amino acid substitution at position 351 is D351Y. In some embodiments, the amino acid substitution at position 351 is D351W. In some embodiments, the amino acid substitution at position 351 is D351F. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that comprises an amino acid substitution at position 387, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 387 is selected from the group consisting of K387R, K387H, K387E, K387D, K387Q, K387N, K387T, K387S, K387C, K387G, K387A, K387V, K387I, K387M, K387P, K387Y, K387W, and K387F. In some embodiments, the amino acid substitution at position 387 is K387R. In some embodiments, the amino acid substitution at position 387 is K387H. In some embodiments, the amino acid substitution at position 387 is K387E. In some embodiments, the amino acid substitution at position 387 is K387D. In some embodiments, the amino acid substitution at position 387 is K387Q. In some embodiments, the amino acid substitution at position 387 is K387N. In some embodiments, the amino acid substitution at position 387 is K387T. In some embodiments, the amino acid substitution at position 387 is K387S. In some embodiments, the amino acid substitution at position 387 is K387C. In some embodiments, the amino acid substitution at position 387 is K387G. In some embodiments, the amino acid substitution at position 387 is K387A. In some embodiments, the amino acid substitution at position 387 is K387V. In some embodiments, the amino acid substitution at position 387 is K387I. In some embodiments, the amino acid substitution at position 387 is K387M. In some embodiments, the amino acid substitution at position 387 is K387P. In some embodiments, the amino acid substitution at position 387 is K387Y. In some embodiments, the amino acid substitution at position 387 is K387W. In some embodiments, the amino acid substitution at position 387 is K387F. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that comprises an amino acid substitution at position 394, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 394 is selected from the group consisting of R394K, R394H, R394E, R394D, R394Q, R394N, R394T, R394S, R394C, R394G, R394A, R394V, R394I, R394M, R394P, R394Y, R394W, and R394F. In some embodiments, the amino acid substitution at position 394 is R394K. In some embodiments, the amino acid substitution at position 394 is R394H. In some embodiments, the amino acid substitution at position 394 is R394E. In some embodiments, the amino acid substitution at position 394 is R394D. In some embodiments, the amino acid substitution at position 394 is R394Q. In some embodiments, the amino acid substitution at position 394 is R394N. In some embodiments, the amino acid substitution at position 394 is R394T. In some embodiments, the amino acid substitution at position 394 is R394S. In some embodiments, the amino acid substitution at position 394 is R394C. In some embodiments, the amino acid substitution at position 394 is R394G. In some embodiments, the amino acid substitution at position 394 is R394A. In some embodiments, the amino acid substitution at position 394 is R394V. In some embodiments, the amino acid substitution at position 394 is R394I. In some embodiments, the amino acid substitution at position 394 is R394M. In some embodiments, the amino acid substitution at position 394 is R394P. In some embodiments, the amino acid substitution at position 394 is R394Y. In some embodiments, the amino acid substitution at position 394 is R394W. In some embodiments, the amino acid substitution at position 394 is R394F. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that comprises an amino acid substitution at position 425, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 425 is selected from the group consisting of R425K, R425H, R425E, R425D, R425Q, R425N, R425T, R425S, R425C, R425G, R425A, R425V, R425I, R425M, R425P, R425Y, R425W, and R425F. In some embodiments, the amino acid substitution at position 425 is R425K. In some embodiments, the amino acid substitution at position 425 is R425H. In some embodiments, the amino acid substitution at position 425 is R425E. In some embodiments, the amino acid substitution at position 425 is R425D. In some embodiments, the amino acid substitution at position 425 is R425Q. In some embodiments, the amino acid substitution at position 425 is R425N. In some embodiments, the amino acid substitution at position 425 is R425T. In some embodiments, the amino acid substitution at position 425 is R425S. In some embodiments, the amino acid substitution at position 425 is R425C. In some embodiments, the amino acid substitution at position 425 is R425G. In some embodiments, the amino acid substitution at position 425 is R425A. In some embodiments, the amino acid substitution at position 425 is R425V. In some embodiments, the amino acid substitution at position 425 is R425I. In some embodiments, the amino acid substitution at position 425 is R425M. In some embodiments, the amino acid substitution at position 425 is R425P. In some embodiments, the amino acid substitution at position 425 is R425Y. In some embodiments, the amino acid substitution at position 425 is R425W. In some embodiments, the amino acid substitution at position 425 is R425F. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that comprises an amino acid substitution at position 427, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 427 is selected from the group consisting of Y427R, Y427K, Y427H, Y427E, Y427D, Y427Q, Y427N, Y427T, Y427S, Y427C, Y427G, Y427A, Y427V, Y427I, Y427M, Y427P, Y427W, and Y427F. In some embodiments, the amino acid substitution at position 427 is Y427R. In some embodiments, the amino acid substitution at position 427 is Y427K. In some embodiments, the amino acid substitution at position 427 is Y427H. In some embodiments, the amino acid substitution at position 427 is Y427E. In some embodiments, the amino acid substitution at position 427 is Y427D. In some embodiments, the amino acid substitution at position 427 is Y427Q. In some embodiments, the amino acid substitution at position 427 is Y427N. In some embodiments, the amino acid substitution at position 427 is Y427T. In some embodiments, the amino acid substitution at position 427 is Y427S. In some embodiments, the amino acid substitution at position 427 is Y427C. In some embodiments, the amino acid substitution at position 427 is Y427G. In some embodiments, the amino acid substitution at position 427 is Y427A. In some embodiments, the amino acid substitution at position 427 is Y427V. In some embodiments, the amino acid substitution at position 427 is Y427I. In some embodiments, the amino acid substitution at position 427 is Y427M. In some embodiments, the amino acid substitution at position 427 is Y427P. In some embodiments, the amino acid substitution at position 427 is Y427W. In some embodiments, the amino acid substitution at position 427 is Y427F. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that comprises an amino acid substitution at position 437, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 437 is selected from the group consisting of N437R, N437K, N437H, N437E, N437D, N437Q, N437T, N437S, N437C, N437G, N437A, N437V, N437I, N437M, N437P, N437Y, N437W, and N437F. In some embodiments, the amino acid substitution at position 437 is N437R. In some embodiments, the amino acid substitution at position 437 is N437K. In some embodiments, the amino acid substitution at position 437 is N437H. In some embodiments, the amino acid substitution at position 437 is N437E. In some embodiments, the amino acid substitution at position 437 is N437D. In some embodiments, the amino acid substitution at position 437 is N437Q. In some embodiments, the amino acid substitution at position 437 is N437T. In some embodiments, the amino acid substitution at position 437 is N437S. In some embodiments, the amino acid substitution at position 437 is N437C. In some embodiments, the amino acid substitution at position 437 is N437G. In some embodiments, the amino acid substitution at position 437 is N437A. In some embodiments, the amino acid substitution at position 437 is N437V. In some embodiments, the amino acid substitution at position 437 is N437I. In some embodiments, the amino acid substitution at position 437 is N437M. In some embodiments, the amino acid substitution at position 437 is N437P. In some embodiments, the amino acid substitution at position 437 is N437Y. In some embodiments, the amino acid substitution at position 437 is N437W. In some embodiments, the amino acid substitution at position 437 is N437F. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that comprises an amino acid substitution at position 441, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 441 is selected from the group consisting of K441R, K441H, K441E, K441D, K441Q, K441N, K441T, K441S, K441C, K441G, K441A, K441V, K441I, K441M, K441P, K441Y, K441W, and K441F. In some embodiments, the amino acid substitution at position 441 is K441R. In some embodiments, the amino acid substitution at position 441 is K441H. In some embodiments, the amino acid substitution at position 441 is K441E. In some embodiments, the amino acid substitution at position 441 is K441D. In some embodiments, the amino acid substitution at position 441 is K441Q. In some embodiments, the amino acid substitution at position 441 is K441N. In some embodiments, the amino acid substitution at position 441 is K441T. In some embodiments, the amino acid substitution at position 441 is K441S. In some embodiments, the amino acid substitution at position 441 is K441C. In some embodiments, the amino acid substitution at position 441 is K441G. In some embodiments, the amino acid substitution at position 441 is K441A. In some embodiments, the amino acid substitution at position 441 is K441V. In some embodiments, the amino acid substitution at position 441 is K441I. In some embodiments, the amino acid substitution at position 441 is K441M. In some embodiments, the amino acid substitution at position 441 is K441P. In some embodiments, the amino acid substitution at position 441 is K441Y. In some embodiments, the amino acid substitution at position 441 is K441W. In some embodiments, the amino acid substitution at position 441 is K441F. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that comprises an amino acid substitution at position 632, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 632 is selected from the group consisting of R632K, R632H, R632E, R632D, R632Q, R632N, R632T, R632S, R632C, R632G, R632A, R632V, R632I, R632M, R632P, R632Y, R632W, and R632F. In some embodiments, the amino acid substitution at position 632 is R632K. In some embodiments, the amino acid substitution at position 632 is R632H. In some embodiments, the amino acid substitution at position 632 is R632E. In some embodiments, the amino acid substitution at position 632 is R632D. In some embodiments, the amino acid substitution at position 632 is R632Q. In some embodiments, the amino acid substitution at position 632 is R632N. In some embodiments, the amino acid substitution at position 632 is R632T. In some embodiments, the amino acid substitution at position 632 is R632S. In some embodiments, the amino acid substitution at position 632 is R632C. In some embodiments, the amino acid substitution at position 632 is R632G. In some embodiments, the amino acid substitution at position 632 is R632A. In some embodiments, the amino acid substitution at position 632 is R632V. In some embodiments, the amino acid substitution at position 632 is R632I. In some embodiments, the amino acid substitution at position 632 is R632M. In some embodiments, the amino acid substitution at position 632 is R632P. In some embodiments, the amino acid substitution at position 632 is R632Y. In some embodiments, the amino acid substitution at position 632 is R632W. In some embodiments, the amino acid substitution at position 632 is R632F. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that comprises an amino acid substitution at position 811, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 811 is selected from the group consisting of H811R, H811K, H811E, H811D, H811Q, H811N, H811T, H811S, H811C, H811G, H811A, H811V, H811I, H811M, H811P, H811Y, H811W, and H811F. In some embodiments, the amino acid substitution at position 811 is H811R. In some embodiments, the amino acid substitution at position 811 is H81 IK. In some embodiments, the amino acid substitution at position 811 is H811E. In some embodiments, the amino acid substitution at position 811 is H81 ID. In some embodiments, the amino acid substitution at position 811 is H811Q. In some embodiments, the amino acid substitution at position 811 is H811N. In some embodiments, the amino acid substitution at position 811 is H81 IT. In some embodiments, the amino acid substitution at position 811 is H81 IS. In some embodiments, the amino acid substitution at position 811 is H811C. In some embodiments, the amino acid substitution at position 811 is H811G. In some embodiments, the amino acid substitution at position 811 is H811A. In some embodiments, the amino acid substitution at position 811 is H811V. In some embodiments, the amino acid substitution at position 811 is H811I. In some embodiments, the amino acid substitution at position 811 is H811M. In some embodiments, the amino acid substitution at position 811 is H8IIP. In some embodiments, the amino acid substitution at position 811 is H811Y. In some embodiments, the amino acid substitution at position 811 is H811W. In some embodiments, the amino acid substitution at position 811 is H811F. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that comprises an amino acid substitution at position 880, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the amino acid substitution at position 880 is selected from the group consisting of F88OR, F880K, F88OH, F88OE, F88OD, F88OQ, F880N, F88OT, F88OS, F88OC, F88OG, F88OA, F88OV, F88OI, F88OM, F88OP, F880Y, and F88OW. In some embodiments, the amino acid substitution at position 880 is F880R. In some embodiments, the amino acid substitution at position 880 is F88OK. In some embodiments, the amino acid substitution at position 880 is F88OH.In some embodiments, the amino acid substitution at position 880 is F88OE. In some embodiments, the amino acid substitution at position 880 is F88OD. In some embodiments, the amino acid substitution at position 880 is F88OQ. In some embodiments, the amino acid substitution at position 880 is F880N. In some embodiments, the amino acid substitution at position 880 is F88OT. In some embodiments, the amino acid substitution at position 880 is F88OS. In some embodiments, the amino acid substitution at position 880 is F88OC. In some embodiments, the amino acid substitution at position 880 is F88OG. In some embodiments, the amino acid substitution at position 880 is F88OA. In some embodiments, the amino acid substitution at position 880 is F880V. In some embodiments, the amino acid substitution at position 880 is F88OI. In some embodiments, the amino acid substitution at position 880 is F88OM. In some embodiments, the amino acid substitution at position 880 is F88OP. In some embodiments, the amino acid substitution at position 880 is F88OY. In some embodiments, the amino acid substitution at position 880 is F88OW. In should be understood that the RNA polymerase variants of the present disclosure may include more than one (e.g., 2, 3, 4, 5, or more) amino acid substitution and / or modification. It should also be understood that any of the RNA polymerase variants may include a G47A substitution and / or an additional C-terminal amino acid, such as glycine, relative to a wild-type RNA polymerase comprising the amino acid sequence of SEQ ID NO: 1. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes (a) an amino acid substitution at positions 350, 351, and 387, and (b) an additional amino acid substitution and / or an amino acid modification at the C-terminal end, relative to wildtype RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the additional amino acid substitution at position 350 is E350A. In some embodiments, the additional amino acid substitution at position 350 is E350K. In some embodiments, the additional amino acid substitution at position 350 is E350N. In some embodiments, the additional amino acid substitution at position 350 is E350W. In some embodiments, the additional amino acid substitution at position 351 is D351V. In some embodiments, the additional amino acid substitution at position 387 is K387S. In some embodiments, the additional amino acid substitution at position 387 is K387H. In some embodiments, the additional amino acid substitution at position 387 is K387N. In some embodiments, the RNA polymerase variant comprises a G47A substitution. In some embodiments, the RNA polymerase variant comprises an additional glycine at the C-terminus. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes (a) an amino acid substitution at positions 437 and 441, and (b) an additional amino acid substitution and / or an amino acid modification at the C-terminal end, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the additional amino acid substitution at position 437 is N437T. In some embodiments, the additional amino acid substitution at position 437 is N437Y. In some embodiments, the additional amino acid substitution at position 437 is N437I. In some embodiments, the additional amino acid substitution at position 437 is N437F. In some embodiments, the additional amino acid substitution at position 441 is K441R. In some embodiments, the RNA polymerase variant comprises a G47A substitution. In some embodiments, the RNA polymerase variant comprises an additional glycine at the C-terminus. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes (a) an amino acid substitution at positions 880, and (b) an amino acid modification at the C-terminal end, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the additional amino acid substitution at position 880 is F880Y. In some embodiments, the amino acid modification at the C-terminal end is an additional alanine (A). In some embodiments, the amino acid modification at the C-terminal end is an additional serine (S). In some embodiments, the amino acid modification at the C-terminal end is an additional threonine (T). In some embodiments, the amino acid modification at the C-terminal end is an additional proline (P). In some embodiments, the RNA polymerase variant comprises a G47A substitution. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes (a) an amino acid substitution at positions 632, 653, and 657, and (b) an additional amino acid substitution and / or an amino acid modification at the C-terminal end, relative to wildtype RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the additional amino acid substitution at position 632 is R632K. In some embodiments, the additional amino acid substitution at position 632 is R632T. In some embodiments, the additional amino acid substitution at position 653 is D653T. In some embodiments, the additional amino acid substitution at position 653 is D653K. In some embodiments, the additional amino acid substitution at position 657 is P657W. In some embodiments, the additional amino acid substitution at position 657 is P657R. In some embodiments, the additional amino acid substitution at position 657 is P657A. In some embodiments, the RNA polymerase variant comprises a G47A substitution. In some embodiments, the RNA polymerase variant comprises an additional glycine at the C-terminus. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes (a) an amino acid substitution at positions 628, 632, 653, and 657, and (b) an additional amino acid substitution and / or an amino acid modification at the C-terminal end, relative to wildtype RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, the additional amino acid substitution at position 628 is S628W. In some embodiments, the additional amino acid substitution at position 632 is R632K. In some embodiments, the additional amino acid substitution at position 632 is R632T. In some embodiments, the additional amino acid substitution at position 653 is D653T. In some embodiments, the additional amino acid substitution at position 653 is D653K. In some embodiments, the additional amino acid substitution at position 657 is P657W. In some embodiments, the additional amino acid substitution at position 657 is P657R. In some embodiments, the additional amino acid substitution at position 657 is P657A. In some embodiments, the RNA polymerase variant comprises a G47A substitution. In some embodiments, the RNA polymerase variant comprises an additional glycine at the C-terminus. In some embodiments, a RNA polymerase variant comprises a RNA polymerase that includes (a) an amino acid substitution at positions 387, 657, and 884, and (b) an additional amino acid substitution and / or an amino acid modification at the C-terminal end, relative to wildtype RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. It should also be understood that the present disclosure encompasses RNA polymerases that have at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% identity to the RNA polymerase variants of described herein. It should also be understood that any of the RNA polymerase variants described herein may share at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95% identity with a RNA polymerase comprising the amino acid sequence of SEQ ID NO: 1. The term “identity” refers to a relationship between the sequences of two or more polypeptides (e.g. enzymes) or polynucleotides (nucleic acids), as determined by comparing the sequences. Identity also refers to the degree of sequence relatedness between or among sequences as determined by the number of matches between strings of two or more amino acid residues or nucleic acid residues. Identity measures the percent of identical matches between the smaller of two or more sequences with gap alignments (if any) addressed by a particular mathematical model or computer program (e.g., “algorithms”). Identity of related proteins or nucleic acids can be readily calculated by known methods. “Percent (%) identity” as it applies to polypeptide or polynucleotide sequences is defined as the percentage of residues (amino acid residues or nucleic acid residues) in the candidate amino acid or nucleic acid sequence that are identical with the residues in the amino acid sequence or nucleic acid sequence of a second sequence after aligning the sequences and introducing gaps, if necessary, to achieve the maximum percent identity. Methods and computer programs for the alignment are well known in the art. It is understood that identity depends on a calculation of percent identity but may differ in value due to gaps and penalties introduced in the calculation. Generally, variants of a particular polynucleotide or polypeptide (e.g., antigen) have at least 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% but less than 100% sequence identity to that particular reference polynucleotide or polypeptide as determined by sequence alignment programs and parameters described herein and known to those skilled in the art. Such tools for alignment include those of the BLAST suite (Stephen F. Altschul, et al (1997), "Gapped BLAST and PSI-BLAST: a new generation of protein database search programs", Nucleic Acids Res. 25:3389-3402). Another popular local alignment technique is based on the Smith-Waterman algorithm (Smith, T.F. & Waterman, M.S. (1981) “Identification of common molecular subsequences.” J. Mol. Biol. 147:195-197). A general global alignment technique based on dynamic programming is the Needleman-Wunsch algorithm (Needleman, S.B. & Wunsch, C.D. (1970) “A general method applicable to the search for similarities in the amino acid sequences of two proteins.” J. Mol. Biol. 48:443-453). More recently a Fast Optimal Global Sequence Alignment Algorithm (FOGSAA) has been developed that purportedly produces global alignment of nucleotide and protein sequences faster than other optimal global alignment methods, including the Needleman-Wunsch algorithm. Nucleotide Cap Analogs Also provided herein are co-transcriptional capping methods for ribonucleic acid (RNA) synthesis, using any of the RNA polymerase variants described herein. That is, RNA is produced in a “one-pot” reaction, without the need for a separate capping reaction. Thus, the methods, in some embodiments, comprise reacting a polynucleotide template with a RNA polymerase variant, nucleoside triphosphates, and a cap analog under in vitro transcription reaction conditions to produce RNA transcript. A cap analog may be, for example, a dinucleotide cap, a trinucleotide cap, or a tetranucleotide cap. In some embodiments, a cap analog is a dinucleotide cap. In some embodiments, a cap analog is a trinucleotide cap. In some embodiments, a cap analog is a tetranucleotide cap. A nucleotide cap (e.g., a trinucleotide cap or tetranucleotide cap), in some embodiments, comprises a compound of formula (I) tautomer or salt thereof, wherein ring B i is a modified or unmodified Guanine; ring B2 and ring B3 each independently is a nucleobase or a modified nucleobase; X2 is O, S(O)P, NR24 or CR25R26 in which p is 0, 1, or 2; Yo is O or CReR?; Y1 is O, S(O)n, CReR?, or NR8, in which n is 0, 1 , or 2; each — is a single bond or absent, wherein when each — is a single bond, Yi is O, S(O)n, CReR?, or NRs; and when each — is absent, Yi is void; Y2 is (OP(O)R4)m in which m is 0, 1, or 2, or -0-(CR4oR4i)u-Qo-(CR42R43)v-, in which Qo is a bond, O, S(O)r, NR44, or CR45R46, r is 0, 1 , or 2, and each of u and v independently is 1, 2, 3 or 4; each R2 and R2' independently is halo, LNA, or OR3; each R3 independently is H, Ci-Ce alkyl, C2-C6 alkenyl, or C2-C6 alkynyl and R3, when being Ci-Ce alkyl, C2-C6 alkenyl, or C2-C6 alkynyl, is optionally substituted with one or more of halo, OH and Ci-Ce alkoxyl that is optionally substituted with one or more OH or OC(O)-Ci-Ce alkyl; each R4 and R4' independently is H, halo, Ci-Ce alkyl, OH, SH, SeH, or BH3"; each of R6, R7, and Rs, independently, is -Q1-T1, in which Qi is a bond or C1-C3 alkyl linker optionally substituted with one or more of halo, cyano, OH and Ci-Ce alkoxy, and Ti is H, halo, OH, COOH, cyano, or Rsi, in which Rsi is C1-C3 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, Ci-C6 alkoxyl, C(O)O-Ci-C6 alkyl, C3-C8 cycloalkyl, C6-Cio aryl, NR31R32, (NR3iR32R33)+, 4 to 12membered heterocycloalkyl, or 5- or 6-membered heteroaryl, and Rsi is optionally substituted with one or more substituents selected from the group consisting of halo, OH, oxo, Ci-Ce alkyl, COOH, C(O)O-Ci-C6 alkyl, cyano, Ci-C6 alkoxyl, NR31R32, (NR3iR32R33)+, C3-C8 cycloalkyl, Ce-Cio aryl, 4 to 12-membered heterocycloalkyl, and 5- or 6-membered heteroaryl; each of Rio, R11, R12, R13 R14, and R15, independently, is -Q2-T2, in which Q2 is a bond or C1-C3 alkyl linker optionally substituted with one or more of halo, cyano, OH and Ci-Ce alkoxy, and T2 is H, halo, OH, NH2, cyano, NO2, N3, Rs2, or ORS2, in which RS2 is Ci-Ce alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C3-C8 cycloalkyl, C6-Cio aryl, NHC(O)-Ci-C6 alkyl, NR31R32, (NR3iR32R33)+, 4 to 12-membered heterocycloalkyl, or 5- or 6-membered heteroaryl, and RS2 is optionally substituted with one or more substituents selected from the group consisting of halo, OH, oxo, Ci-Ce alkyl, COOH, C(O)O-Ci-Ce alkyl, cyano, Ci -Ce alkoxyl, NR31R32, (NR3iR32R33)+, C3-C8 cycloalkyl, Ce-Cio aryl, 4 to 12-membered heterocycloalkyl, and 5- or 6- membered heteroaryl; or alternatively R12 together with R14 is oxo, or R13 together with R15 is oxo, each of R20, R21, R22, and R23 independently is -Q3-T3, in which Q3 is a bond or C1-C3 alkyl linker optionally substituted with one or more of halo, cyano, OH and Ci-Ce alkoxy, and T3 is H, halo, OH, NH2, cyano, NO2, N3, Rs3, or ORs3, in which Rs3 is Ci-Ce alkyl, C2-Ce alkenyl, C2-C6 alkynyl, C3-C8 cycloalkyl, Ce-Cio aryl, NHC(O)-Ci-C6 alkyl, mono-Ci-Ce alkylamino, di-Ci-Ce alkylamino, 4 to 12-membered heterocycloalkyl, or 5- or 6-membered heteroaryl, and RS3 is optionally substituted with one or more substituents selected from the group consisting of halo, OH, oxo, Ci-Ce alkyl, COOH, C(O)O-Ci-Ce alkyl, cyano, Ci-Ce alkoxyl, amino, mono-Ci-Ce alkylamino, di-Ci-Ce alkylamino, C3-C8 cycloalkyl, Ce-Cio aryl, 4 to 12-membered heterocycloalkyl, and 5- or 6-membered heteroaryl; each of R24, R25, and R26 independently is H or Ci-Ce alkyl; each of R27 and R28 independently is H or OR29; or R27 and R28 together form O-R30-O; each R29 independently is H, Ci-Ce alkyl, C2-C6 alkenyl, or C2-C6 alkynyl and R29, when being Ci-Ce alkyl, C2-C6 alkenyl, or C2-C6 alkynyl, is optionally substituted with one or more of halo, OH and Ci-Ce alkoxyl that is optionally substituted with one or more OH or OC(O)-Ci-C6 alkyl; R30 is Ci-Ce alkylene optionally substituted with one or more of halo, OH and Ci-Ce alkoxyl; each of R31, R32, and R33, independently is H, Ci-Ce alkyl, C3-C8 cycloalkyl, Ce-Cio aryl, 4 to 12-membered heterocycloalkyl, or 5- or 6-membered heteroaryl; each of R40, R41, R42, and R43 independently is H, halo, OH, cyano, N3, OP(O)R4?R48, or Ci-Ce alkyl optionally substituted with one or more OP(O)R4?R48, or one R41 and one R43, together with the carbon atoms to which they are attached and Qo, form C4-C10 cycloalkyl, 4- to 14-membered heterocycloalkyl, Ce-Cio aryl, or 5- to 14-membered heteroaryl, and each of the cycloalkyl, heterocycloalkyl, phenyl, or 5- to 6-membered heteroaryl is optionally substituted with one or more of OH, halo, cyano, N3, oxo, OP(O)R4?R48, C1-C6 alkyl, C1-C6 haloalkyl, COOH, C(O)O-Ci-C6 alkyl, Ci-Ce alkoxyl, Ci-Ce haloalkoxyl, amino, mono-Ci-Ce alkylamino, and di-Ci-Ce alkylamino; R44 is H, C1-C6 alkyl, or an amine protecting group; each of R45 and R46 independently is H, OP(O)R4?R48, or Ci-Ce alkyl optionally substituted with one or more OP(O)R4?R48, and each of R47 and R48, independently is H, halo, Ci-Ce alkyl, OH, SH, SeH, or BHs'. It should be understood that a cap analog, as provided herein, may include any of the cap analogs described in international publication WO 2017 / 066797, published on 20 April 2017, incorporated by reference herein in its entirety. In some embodiments, the B2 middle position can be a non-ribose molecule, such as arabinose. In some embodiments R2 is ethyl-based. Thus, in some embodiments, a trinucleotide cap comprises the following structure: Me-# ’A . N si N OH OH OH z-N HO OH O i HO-P^O HO OH (W. In other embodiments, a trinucleotide cap comprises the following structure: NH2 HO OH O 0 ~ i             O             ar j              O-p-O OH             s          1  \ £k »   < !             § i                      \        / !                        ? s HSH |       I O O* i-.                                      S3                         ••                                         / / HO“P~O N’ yo o \ / HO OH (III). In yet other embodiments, a trinucleotide cap comprises the following structure: HO OH (IV). In still other embodiments, a trinucleotide cap comprises the following structure: HO OH O  O   p 0....p... 0... p.....0...p ...0                 'yr.?.".’ OH OH  OH W H„N o 0-^ HO-P-O H7 1 HO OH (V). Thus, in some embodiments, a tetranucleotide cap comprises the following structure: In other embodiments, a tetranucleotide cap comprises the following structure: In yet other embodiments, a tetranucleotide cap comprises the following structure: In yet other embodiments, a tetranucleotide cap comprises the following structure: HO OH      NH2 (IX) In some embodiments, R is an alkyl (e.g., Ci-Ce alkyl). In some embodiments, R is a methyl group (e.g., Ci alkyl). In some embodiments, R is an ethyl group (e.g., C2 alkyl). In some embodiments, R is a hydrogen. A trinucleotide cap, in some embodiments, comprises a sequence selected from the following sequences: GAA, GAC, GAG, GAU, GCA, GCC, GCG, GCU, GGA, GGC, GGG, GGU, GUA, GUC, GUG, and GUU. In some embodiments, a trinucleotide cap comprises GAA. In some embodiments, a trinucleotide cap comprises GAC. In some embodiments, a trinucleotide cap comprises GAG. In some embodiments, a trinucleotide cap comprises GAU. In some embodiments, a trinucleotide cap comprises GCA. In some embodiments, a trinucleotide cap comprises GCC. In some embodiments, a trinucleotide cap comprises GCG. In some embodiments, a trinucleotide cap comprises GCU. In some embodiments, a trinucleotide cap comprises GGA. In some embodiments, a trinucleotide cap comprises GGC. In some embodiments, a trinucleotide cap comprises GGG. In some embodiments, a trinucleotide cap comprises GGU. In some embodiments, a trinucleotide cap comprises GUA. In some embodiments, a trinucleotide cap comprises GUC. In some embodiments, a trinucleotide cap comprises GUG. In some embodiments, a trinucleotide cap comprises GUU. In some embodiments, a trinucleotide cap comprises a sequence selected from the following sequences: m7GpppApA, m7GpppApC, m7GpppApG, m7GpppApU, m7GpppCpA, m7GpppCpC, m7GpppCpG, m7GpppCpU, m7GpppGpA, m7GpppGpC, m7GpppGpG, m7GpppGpU, m7GpppUpA, m7GpppUpC, m7GpppUpG, and m7GpppUpU. In some embodiments, a trinucleotide cap comprises m7GpppApA. In some embodiments, a trinucleotide cap comprises m7GpppApC. In some embodiments, a trinucleotide cap comprises m7GpppApG. In some embodiments, a trinucleotide cap comprises m7GpppApU. In some embodiments, a trinucleotide cap comprises m7GpppCpA. In some embodiments, a trinucleotide cap comprises m7GpppCpC. In some embodiments, a trinucleotide cap comprises m7GpppCpG. In some embodiments, a trinucleotide cap comprises m7GpppCpU. In some embodiments, a trinucleotide cap comprises m7GpppGpA. In some embodiments, a trinucleotide cap comprises m7GpppGpC. In some embodiments, a trinucleotide cap comprises m7GpppGpG. In some embodiments, a trinucleotide cap comprises m7GpppGpU. In some embodiments, a trinucleotide cap comprises m7GpppUpA. In some embodiments, a trinucleotide cap comprises m7GpppUpC. In some embodiments, a trinucleotide cap comprises m7GpppUpG. In some embodiments, a trinucleotide cap comprises m7GpppUpU. A trinucleotide cap, in some embodiments, comprises a sequence selected from the following sequences: m7G3'OMepppApA, m7G3'OMepppApC, m7G3'OMepppApG, m7G3'OMepppApU, m7G3'OMepppCpA, m7G3'OMepppCpC, m7G3'OMepppCpG, m7G3'OMepppCpU, m7G3'OMePPpGpA, m7G3'OMePPpGpC, m7G3'OMePPpGpG, m7G3'0MePPpGpU, m7G3'OMePPpUpA, m7G3'OMePPpUpC, m7G3'OMePPpUpG, and m7G3'0MepppUpU. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpApA. In some embodiments, a trinucleotide cap comprises m7G3'OMepppApC. In some embodiments, a trinucleotide cap comprises m7G3'OMepppApG. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpApU. In some embodiments, a trinucleotide cap comprises m7G3'OMepppCpA. In some embodiments, a trinucleotide cap comprises m7G3'OMepppCpC. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpCpG. In some embodiments, a trinucleotide cap comprises m7G3'OMepppCpU. In some embodiments, a trinucleotide cap comprises m7G3'OMepppGpA. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpGpC. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpGpG. In some embodiments, a trinucleotide cap comprises m7G3'OMepppGpU. In some embodiments, a trinucleotide cap comprises m7G3'oMepppUpA. In some embodiments, a trinucleotide cap comprises m7G3'OMepppUpC. In some embodiments, a trinucleotide cap comprises m7G3'OMepppUpG. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpUpU. A trinucleotide cap, in other embodiments, comprises a sequence selected from the following sequences: m7G3'OMepppA2'OMepA, m7G3'OMepppA2'OMepC, m7G3'OMePPpA2'OMepG, m7G3'OMePPpA2'OMepU, m7G3'OMePPpC2'OMepA, m7G3'OMepppC2'OMepC, m7G3'OMePPpC2'OMepG, m7G3'OMePPpC2'OMepU, m7G3'OMepppG2'OMepA, m7G3'OMepppG2'OMepC, m7G3'OMePPpG2'OMepG, m7G3'OMePPpG2'OMepU, m7G3'OMepppU2'OMepA, m7G3'OMepppU2'OMepC, m7G3'OMePPpU2'OMepG, and m7G3'OMepppU2'OMepU. In some embodiments, a trinucleotide cap comprises m7G3'OMepppA2'OMepA. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpA2'OMepC. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpA2'oMepG. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpA2'oMepU. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpC2'OMepA. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpC2'OMepC. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpC2'OMepG. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpC2'OMepU. In some embodiments, a trinucleotide cap comprises m7G3'OMepppG2'OMepA. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpG2'OMepC. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpG2'OMepG. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpG2'OMepU. In some embodiments, a trinucleotide cap comprises m7G3'OMepppU2'OMepA. In some embodiments, a trinucleotide cap comprises m7G3'oMepppU2'oMepC. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpU2'OMepG. In some embodiments, a trinucleotide cap comprises m7G3'OMePPpU 2'OMepU. A trinucleotide cap, in still other embodiments, comprises a sequence selected from the following sequences: m7GpppA2'OMepA, m7GpppA2'OMepC, m7GpppA2'OMepG, m7GpppA2'OMepU, m7GpppC2'OMepA, m7GpppC2'OMepC, m7GpppC2'OMepG, m7GpppC2'OMepU, m7GpppG2'OMepA, m7GpppG2'OMEpC, m7GpppG2'OMepG, m7GpppG2'OMepU, m7GpppU2'OMepA, m7GpppU2'oMepC, m7GpppU2'oMepG, and m7GpppU2'oMepU. In some embodiments, a trinucleotide cap comprises m7GpppA2'0MepA. In some embodiments, a trinucleotide cap comprises m7GpppA2'OMepC. In some embodiments, a trinucleotide cap comprises m7GpppA2'oMepG. In some embodiments, a trinucleotide cap comprises m7GpppA2'0MepU. In some embodiments, a trinucleotide cap comprises m7GpppC2'oMepA. In some embodiments, a trinucleotide cap comprises m7GpppC2'oMepC. In some embodiments, a trinucleotide cap comprises m7GpppC2'OMepG. In some embodiments, a trinucleotide cap comprises m7GpppC2'OMepU. In some embodiments, a trinucleotide cap comprises m7GpppG2'OMepA. In some embodiments, a trinucleotide cap comprises m7GpppG2'OMepC. In some embodiments, a trinucleotide cap comprises m7GpppG2'OMepG. In some embodiments, a trinucleotide cap comprises m7GpppG2'OMepU. In some embodiments, a trinucleotide cap comprises m7GpppU2'OMepA. In some embodiments, a trinucleotide cap comprises m7GpppU2'OMepC. In some embodiments, a trinucleotide cap comprises m7GpppU2'OMepG. In some embodiments, a trinucleotide cap comprises m7GpppU2'OMepU. In some embodiments, a trinucleotide cap comprises m7Gppprn6A2’OmepG. In some embodiments, a trinucleotide cap comprises m7Gpppe6A2 OmepG. In some embodiments, a trinucleotide cap comprises GAG. In some embodiments, a trinucleotide cap comprises GCG. In some embodiments, a trinucleotide cap comprises GUG. In some embodiments, a trinucleotide cap comprises GGG. In some embodiments, a trinucleotide cap comprises any one of the following structures: In some embodiments, a tetranucleotide cap comprises GGAG. (ii); or (iii). In some embodiments, a tetranucleotide cap comprises any one of the following structures: In vitro Transcription Methods Some aspects of the present disclosure provide methods of producing (synthesizing) a RNA transcript (e.g., mRNA transcript) comprising contacting a DNA template with a RNA polymerase (e.g., a T7 RNA polymerase such as a T7 RNA polymerase variant) under conditions that result in the production of RNA transcript. In some embodiments, the methods comprise contacting a DNA template with a T7 RNA polymerase variant that comprises an (at least one) additional C terminal amino acid (e.g., Gly, Ala, GlyGly, AlaAla, GlyAla, or AlaGly). In some aspects, the present disclosure provides methods of performing an IVT reaction, comprising contacting a DNA template with the RNA polymerase (e.g., a T7 RNA polymerase, such as a T7 RNA polymerase variant) in the presence of nucleoside triphosphates and buffer under conditions that result in the production of RNA transcripts. Other aspects of the present disclosure provide co-transcriptional capping methods that comprise reacting a polynucleotide template with a T7 RNA polymerase variant, nucleoside triphosphates, and a cap analog under in vitro transcription reaction conditions to produce RNA transcript. In some embodiments, a co-transcriptional capping method for RNA synthesis comprises reacting a polynucleotide template with (a) a T7 RNA polymerase variant comprising at least one amino acid substitution, relative to wild-type RNA polymerase, that causes at least one loop structure of the RNA polymerase variant to undergo a conformational change to a helix structure as the RNA polymerase variant transitions from an initiation complex to an elongation complex (e.g., at least one amino acid substitution positions 42, 43, 44, 45, 46, and / or 47), (b) nucleoside triphosphates, and (c) a trinucleotide cap comprising sequence GpppAs'OmepG, under in vitro transcription reaction conditions to produce RNA transcript, wherein the polynucleotide template includes a 2'-deoxythymidine residue at template position +1. IVT conditions typically require a purified linear DNA template containing a promoter, nucleoside triphosphates, a buffer system that includes dithiothreitol (DTT) and magnesium ions, and a RNA polymerase. The exact conditions used in the transcription reaction depend on the amount of RNA needed for a specific application. Typical IVT reactions are performed by incubating a DNA template with a RNA polymerase and nucleoside triphosphates, including GTP, ATP, CTP, and UTP (or nucleotide analogs) in a transcription buffer. A RNA transcript having a 5' terminal guanosine triphosphate is produced from this reaction. A deoxyribonucleic acid (DNA) is simply a nucleic acid template for RNA polymerase. A DNA template may include a polynucleotide encoding a polypeptide of interest (e.g., an antigenic polypeptide). A DNA template, in some embodiments, includes a RNA polymerase promoter (e.g., a T7 RNA polymerase promoter) located 5' from and operably linked to polynucleotide encoding a polypeptide of interest. A DNA template may also include a nucleotide sequence encoding a polyadenylation (polyA) tail located at the 3' end of the gene of interest. Polypeptides of interest include, but are not limited to, biologies, antibodies, antigens (vaccines), and therapeutic proteins. The term “protein” encompasses peptides. A RNA transcript, in some embodiments, is the product of an IVT reaction. A RNA transcript, in some embodiments, is a messenger RNA (mRNA) that includes a nucleotide sequence encoding a polypeptide of interest linked to a polyA tail. In some embodiments, the mRNA is modified mRNA (mmRNA), which includes at least one modified nucleotide. A nucleotide includes a nitrogenous base, a five-carbon sugar (ribose or deoxyribose), and at least one phosphate group. Nucleotides include nucleoside monophosphates, nucleoside diphosphates, and nucleoside triphosphates. A nucleoside monophosphate (NMP) includes a nucleobase linked to a ribose and a single phosphate; a nucleoside diphosphate (NDP) includes a nucleobase linked to a ribose and two phosphates; and a nucleoside triphosphate (NTP) includes a nucleobase linked to a ribose and three phosphates. Nucleotide analogs are compounds that have the general structure of a nucleotide or are structurally similar to a nucleotide. Nucleotide analogs, for example, include an analog of the nucleobase, an analog of the sugar and / or an analog of the phosphate group(s) of a nucleotide. A nucleoside includes a nitrogenous base and a 5-carbon sugar. Thus, a nucleoside plus a phosphate group yields a nucleotide. Nucleoside analogs are compounds that have the general structure of a nucleoside or are structurally similar to a nucleoside. Nucleoside analogs, for example, include an analog of the nucleobase and / or an analog of the sugar of a nucleoside. It should be understood that the term “nucleotide” includes naturally-occurring nucleotides, synthetic nucleotides and modified nucleotides, unless indicated otherwise. Examples of naturally-occurring nucleotides used for the production of RNA, e.g., in an IVT reaction, as provided herein include adenosine triphosphate (ATP), guanosine triphosphate (GTP), cytidine triphosphate (CTP), uridine triphosphate (UTP), and 5-methyluridine triphosphate (m5UTP). In some embodiments, adenosine diphosphate (ADP), guanosine diphosphate (GDP), cytidine diphosphate (CDP), and / or uridine diphosphate (UDP) are used. Examples of nucleotide analogs include, but are not limited to, antiviral nucleotide analogs, phosphate analogs (soluble or immobilized, hydrolyzable or non-hydrolyzable), dinucleotide, trinucleotide, tetranucleotide, e.g., a cap analog, or a precursor / substrate for enzymatic capping (vaccinia or ligase), a nucleotide labeled with a functional group to facilitate 45 ligation / conjugation of cap or 5' moiety (IRES), a nucleotide labeled with a 5' PO4 to facilitate ligation of cap or 5' moiety, or a nucleotide labeled with a functional group / protecting group that can be chemically or enzymatically cleaved. Examples of antiviral nucleotide / nucleoside analogs include, but are not limited, to Ganciclovir, Entecavir, Telbivudine, Vidarabine and Cidofovir. Modified nucleotides may include modified nucleobases. For example, a RNA transcript (e.g., mRNA transcript) of the present disclosure may include a modified nucleobase selected from pseudouridine (\| / ), 1-methylpseudouridine (ml\| / ), 1-ethylpseudouridine, 2-thiouridine, 4’-thiouridine, 2-thio-l-methyl-l-deaza-pseudouridine, 2-thio-l-methyl-pseudouridine, 2-thio-5-aza-uridine , 2-thio-dihydropseudouridine, 2-thio-dihydrouridine, 2-thio-pseudouridine, 4-methoxy-2-thio-pseudouridine, 4-methoxy-pseudouridine, 4-thio-l-methyl-pseudouridine, 4-thio-pseudouridine, 5-aza-uridine, dihydropseudouridine, 5-methyluridine, 5-methoxyuridine (mo5U) and 2’-O-methyl uridine. In some embodiments, a RNA transcript (e.g., mRNA transcript) includes a combination of at least two (e.g., 2, 3, 4 or more) of the foregoing modified nucleobases. The nucleoside triphosphates (NTPs) as provided herein may comprise unmodified or modified ATP, modified or unmodified UTP, modified or unmodified GTP, and / or modified or unmodified CTP. In some embodiments, NTPs of an IVT reaction comprise unmodified ATP. In some embodiments, NTPs of an IVT reaction comprise modified ATP. In some embodiments, NTPs of an IVT reaction comprise unmodified UTP. In some embodiments, NTPs of an IVT reaction comprise modified UTP. In some embodiments, NTPs of an IVT reaction comprise unmodified GTP. In some embodiments, NTPs of an IVT reaction comprise modified GTP. In some embodiments, NTPs of an IVT reaction comprise unmodified CTP. In some embodiments, NTPs of an IVT reaction comprise modified CTP. The concentration of nucleoside triphosphates and cap analog present in an IVT reaction may vary. In some embodiments, NTPs and cap analog are present in the reaction at equimolar concentrations. In some embodiments, the molar ratio of cap analog (e.g., trinucleotide cap) to nucleoside triphosphates in the reaction is greater than 1:1. For example, the molar ratio of cap analog to nucleoside triphosphates in the reaction may be 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, 15:1, 20:1, 25:1, 50:1, or 100:1. In some embodiments, the molar ratio of cap analog (e.g., trinucleotide cap) to nucleoside triphosphates in the reaction is less than 1:1. For example, the molar ratio of cap analog (e.g., trinucleotide cap) to nucleoside triphosphates in the reaction may be 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:15, 1:20, 1:25, 1:50, or 1:100. The composition of NTPs in an IVT reaction may also vary. For example, ATP may be used in excess of GTP, CTP and UTP. As a non-limiting example, an IVT reaction may include 7.5 millimolar GTP, 7.5 millimolar CTP, 7.5 millimolar UTP, and 3.75 millimolar ATP. The same IVT reaction may include 3.75 millimolar cap analog (e.g., trinucleotide cap). In some embodiments, the molar ratio of G:C:U:A:cap is 1:1:1:0.5:0.5. In some embodiments, the molar ratio of G:C:U:A:cap is 1:1:0.5:1:0.5. In some embodiments, the molar ratio of G:C:U:A:cap is 1:0.5:1:1:0.5. In some embodiments, the molar ratio of G:C:U:A:cap is 0.5:1:1:1:0.5. In some embodiments, a RNA transcript (e.g., mRNA transcript) includes a modified nucleobase selected from pseudouridine (\| / ), 1-methylpseudouridine (m^), 5-methoxyuridine (mo5U), 5-methylcytidine (m5C), a-thio-guanosine and a-thio-adenosine. In some embodiments, a RNA transcript (e.g., mRNA transcript) includes a combination of at least two (e.g., 2, 3, 4 or more) of the foregoing modified nucleobases. In some embodiments, a RNA transcript (e.g., mRNA transcript) includes pseudouridine (\| / )- In some embodiments, a RNA transcript (e.g., mRNA transcript) includes 1-methylpseudouridine (m1^). In some embodiments, a RNA transcript (e.g., mRNA transcript) includes 5-methoxyuridine (mo5U). In some embodiments, a RNA transcript (e.g., mRNA transcript) includes 5-methylcytidine (m5C). In some embodiments, a RNA transcript (e.g., mRNA transcript) includes a-thio-guanosine. In some embodiments, a RNA transcript (e.g., mRNA transcript) includes a-thio-adenosine. In some embodiments, the polynucleotide (e.g., RNA polynucleotide, such as mRNA polynucleotide) is uniformly modified (e.g., fully modified, modified throughout the entire sequence) for a particular modification. For example, a polynucleotide can be uniformly modified with 1-methylpseudouridine (m1^), meaning that all uridine residues in the mRNA sequence are replaced with 1-methylpseudouridine (m1!] / ). Similarly, a polynucleotide can be uniformly modified for any type of nucleoside residue present in the sequence by replacement with a modified residue such as any of those set forth above. Alternatively, the polynucleotide (e.g., RNA polynucleotide, such as mRNA polynucleotide) may not be uniformly modified (e.g., partially modified, part of the sequence is modified). Each possibility represents a separate embodiment of the present invention. In some embodiments, the buffer system contains tris. The concentration of tris used in an IVT reaction, for example, may be at least 10 mM, at least 20 mM, at least 30 mM, at least 40 mM, at least 50 mM, at least 60 mM, at least 70 mM, at least 80 mM, at least 90 mM, at least 100 mM or at least 110 mM phosphate. In some embodiments, the concentration of phosphate is 20-60 mM or 10-100 mM. In some embodiments, the buffer system contains dithiothreitol (DTT). The concentration of DTT used in an IVT reaction, for example, may be at least 1 mM, at least 5 mM, or at least 50 mM. In some embodiments, the concentration of DTT used in an IVT reaction is 1-50 mM or 550 mM. In some embodiments, the concentration of DTT used in an IVT reaction is 5 mM. In some embodiments, the buffer system contains magnesium. In some embodiments, the molar ratio of NTP to magnesium ions (Mg2+; e.g., MgCh) present in an IVT reaction is 1:1 to 1:5. For example, the molar ratio of NTP to magnesium ions maybe 1:1, 1:2, 1:3, 1:4 or 1:5. In some embodiments, the molar ratio of NTP plus cap analog {e.g., trinucleotide cap, such as GAG) to magnesium ions (Mg2+; e.g., MgCh) present in an IVT reaction is 1:1 to 1:5. For example, the molar ratio of NTP+trinucleotide cap {e.g., GAG) to magnesium ions may be 1:1, 1:2, 1:3, 1:4 or 1:5. In some embodiments, the buffer system contains Tris-HCl, spermidine {e.g., at a concentration of 1-30 mM), TRITON® X-100 (polyethylene glycol p-(l,l,3,3-tetramethylbutyl)-phenyl ether) and / or polyethylene glycol (PEG). The addition of nucleoside triphosphates (NTPs) to the 3' end of a growing RNA strand is catalyzed by a polymerase, such as T7 RNA polymerase, for example, any one or more of the T7 RNA polymerase variants {e.g., G47A) of the present disclosure. In some embodiments, the RNA polymerase {e.g., T7 RNA polymerase variant) is present in a reaction {e.g., an IVT reaction) at a concentration of 0.01 mg / ml to 1 mg / ml. For example, the RNA polymerase may be present in a reaction at a concentration of 0.01 mg / mL, 0.05 mg / ml, 0.1 mg / ml, 0.5 mg / ml or 1.0 mg / ml. Surprisingly, use of the combination of a T7 RNA polymerase variant {e.g., G47A) as provided herein with a cap analog {e.g., GpppAi'omepG), in an in vitro transcription reaction, for example, results in the production of RNA transcript, wherein greater than 80% of the RNA transcript produced includes a functional cap. In some embodiments, greater than 85% of the RNA transcript produced includes a functional cap. In some embodiments, greater than 90% of the RNA transcript produced includes a functional cap. In some embodiments, greater than 95% of the RNA transcript produced includes a functional cap. In some embodiments, greater than 96% of the RNA transcript produced includes a functional cap. In some embodiments, greater than 97% of the RNA transcript produced includes a functional cap. In some embodiments, greater than 98% of the RNA transcript produced includes a functional cap. In some embodiments, greater than 99% of the RNA transcript produced includes a functional cap. Also surprising was the finding that use of a polynucleotide template that includes a 2'-deoxythymidine residue or 2'-deoxycytidine residue at template position +1 results in the production of RNA transcript, wherein greater than 80% {e.g., greater than 85%, greater than 90%, or greater than 95%) of the RNA transcript produced includes a functional cap. Thus, in some embodiments, a polynucleotide {e.g., DNA) template used, for example, in an IVT reaction, includes a 2'-deoxythymidine residue at template position +1. In other embodiments, a polynucleotide (e.g., DNA) template used, for example, in an IVT reaction, includes a 2'-deoxycytidine residue at template position +1. Multi-Substitution RNA T7 Polymerases Variants Various aspects of the present disclosure provide RNA T7 polymerase variants that comprise at least two amino acid substitutions. In some embodiments, an RNA T7 polymerase variant comprises at least three amino acid substitutions. In some embodiments, an RNA T7 polymerase variant comprises at least four amino acid substitutions. In some embodiments, an RNA T7 polymerase variant comprises at least five amino acid substitutions. A RNA T7 polymerase variant that includes a G47A substitution, relative to a wild-type T7 RNA polymerase (e.g., comprising the amino acid sequence of SEQ ID NO: 1) may be referred to herein as a “G47A T7 Pol variant.” Table 1 below provides examples of multi-substitution RNA T7 polymerase variants of the present disclosure. It should be understood that each of the T7 polymerase variants included in Table 1 comprises a G47A substitution, relative to a wild-type T7 RNA polymerase that comprises the amino acid sequence of SEQ ID NO: 1. It should also be understood that each of the T7 polymerase variants included in Table 1 comprises an additional C-terminal amino acid at position 884, relative to a wild-type T7 RNA polymerase that comprises the amino acid sequence of SEQ ID NO: 1. This additional C-terminal amino acid is glycine (G884) unless otherwise indicated: G884T denotes a T7 RNA polymerase variant that includes a threonine at position 884 (instead of the glycine); G884S denotes a T7 RNA polymerase variant that includes a serine at position 884 (instead of the glycine); G884P denotes a T7 RNA polymerase variant that includes a proline at position 884 (instead of the glycine); and G884A denotes a T7 RNA polymerase variant that includes an alanine at position 884 (instead of the glycine). All substitutions in Table 1 are relative to a wild-type T7 RNA polymerase variant that comprises the amino acid sequence of SEQ ID NO: 1. Table 1. Multi-Substitution RNA T7 Polymerase Variants Substitutions and / or C-terminal Modification SEQ ID NO: G47A, K387N, G884 61 G47A, G884T 62 G47A, G884T, K387N 63 G47A, G884S 64 G47A, G884S, K387N 65 G47A, G884P 66 Substitutions and / or C-terminal Modification SEQ ID NO: G47A, G884P, K387N 67 G47A, D653W, G884 68 G47A, D653W, K387N, G884 69 G47A, D653W, G884T 70 G47A, D653W, G884T, K387N 71 G47A, D653W, G884S 72 G47A, D653W, G884S, K387N 73 G47A, D653W, G884P 74 G47A, D653W, G884P, K387N 75 G47A, D653T, G884 76 G47A, D653T, K387N, G884 77 G47A, D653T, G884T 78 G47A, D653T, G884T, K387N 79 G47A, D653T, G884S 80 G47A, D653T, G884S, K387N 81 G47A, D653T, G884P 82 G47A, D653T, G884P, K387N 83 G47A, D653K, G884 84 G47A, D653K, K387N, G884 85 G47A, D653K, G884T 86 G47A, D653K, G884T, K387N 87 G47A, D653K, G884S 88 G47A, D653K, G884S, K387N 89 G47A, D653K, G884P 90 G47A, D653K, G884P, K387N 91 G47A, K387S, G884 92 G47A, K387H, G884 93 G47A, E350A, G884 94 G47A, E350A, K387S, G884 95 G47A, E350A, K387H, G884 96 G47A, E350A, K387N, G884 97 G47A, E350K, G884 98 G47A, E350K, K387S, G884 99 G47A, E350K, K387H, G884 100 G47A, E350K, K387N, G884 101 G47A, E350N, G884 102 G47A, E350N, K387S, G884 103 G47A, E350N, K387H, G884 104 G47A, E350N, K387N, G884 105 G47A, E350W, G884 106 G47A, E350W, K387S, G884 107 G47A, E350W, K387H, G884 108 Substitutions and / or C-terminal Modification SEQ ID NO: G47A, E350W, K387N, G884 109 G47A, D351V, G884 110 G47A, D351V, K387S, G884 111 G47A, D351V, K387H, G884 112 G47A, D351V, K387N, G884 113 G47A, D351V, E350A, G884 114 G47A, D351V, E350A, K387S, G884 115 G47A, D351V, E350A, K387H, G884 116 G47A, D351V, E350A, K387N, G884 117 G47A, D351V, E350K, G884 118 G47A, D351V, E350K, K387S, G884 119 G47A, D351V, E350K, K387H, G884 120 G47A, D351V, E350K, K387N, G884 121 G47A, D351V, E350N, G884 122 G47A, D351V, E350N, K387S, G884 123 G47A, D351V, E350N, K387H, G884 124 G47A, D351V, E350N, K387N, G884 125 G47A, D351V, E350W, G884 126 G47A, D351V, E350W, K387S, G884 127 G47A, D351V, E350W, K387H, G884 128 G47A, D351V, E350W, K387N, G884 129 G47A, D653A, G884 130 G47A, D653F, G884 131 G47A, D653G, G884 132 G47A, D653H, G884 133 G47A, D653I, G884 134 G47A, D653L, G884 135 G47A, D653M, G884 136 G47A, D653N, G884 137 G47A, D653P, G884 138 G47A, D653Q, G884 139 G47A, D653R, G884 140 G47A, D653S, G884 141 G47A, D653V, G884 142 G47A, D653Y, G884 143 G47A, P657W, G884 144 G47A, P657R, G884 145 G47A, P657A, G884 146 G47A, D653W, P657W, G884 147 G47A, D653W, P657R, G884 148 G47A, D653W, P657A, G884 149 G47A, D653T, P657W, G884 150 Substitutions and / or C-terminal Modification SEQ ID NO: G47A, D653T, P657R, G884 151 G47A, D653T, P657A, G884 152 G47A, D653K, P657W, G884 153 G47A, D653K, P657R, G884 154 G47A, D653K, P657A, G884 155 G47A, N437T, G884 156 G47A, N437Y, G884 157 G47A, N437I, G884 158 G47A, N437F, G884 159 G47A, K441R, G884 160 G47A, K441R, N437T, G884 161 G47A, K441R, N437Y, G884 162 G47A, K441R, N437I, G884 163 G47A, K441R, N437F, G884 164 G47A, S628W, G884 165 G47A, D506W, G884 166 G47A, D506W, S628W, G884 167 G47A, D506F, G884 168 G47A, D506F, S628W, G884 169 G47A, D506Y, G884 170 G47A, D506Y, S628W, G884 171 G47A, D506R, G884 172 G47A, D506R, S628W, G884 173 G47A, D506L, G884 174 G47A, D506L, S628W, G884 175 G47A, D653C, G884 176 G47A, D653E, G884 177 G47A, R632K, G884 178 G47A, R632T, G884 179 G47A, P657W, R632K, G884 180 G47A, P657W, R632T, G884 181 G47A, P657R, R632K, G884 182 G47A, P657R, R632T, G884 183 G47A, P657A, R632K, G884 184 G47A, P657A, R632T, G884 185 G47A, D653W, R632K, G884 186 G47A, D653W, R632T, G884 187 G47A, D653W, P657W, R632K, G884 188 G47A, D653W, P657W, R632T, G884 189 G47A, D653W, P657R, R632K, G884 190 G47A, D653W, P657R, R632T, G884 191 G47A, D653W, P657A, R632K, G884 192 Substitutions and / or C-terminal Modification SEQ ID NO: G47A, D653W, P657A, R632T, G884 193 G47A, D653F, R632K, G884 194 G47A, D653F, R632T, G884 195 G47A, D653F, P657W, G884 196 G47A, D653F, P657W, R632K, G884 197 G47A, D653F, P657W, R632T, G884 198 G47A, D653F, P657R, G884 199 G47A, D653F, P657R, R632K, G884 200 G47A, D653F, P657R, R632T, G884 201 G47A, D653F, P657A, G884 202 G47A, D653F, P657A, R632K, G884 203 G47A, D653F, P657A, R632T, G884 204 G47A, D653Y, R632K, G884 205 G47A, D653Y, R632T, G884 206 G47A, D653Y, P657W, G884 207 G47A, D653Y, P657W, R632K, G884 208 G47A, D653Y, P657W, R632T, G884 209 G47A, D653Y, P657R, G884 210 G47A, D653Y, P657R, R632K, G884 211 G47A, D653Y, P657R, R632T, G884 212 G47A, D653Y, P657A, G884 213 G47A, D653Y, P657A, R632K, G884 214 G47A, D653Y, P657A, R632T, G884 215 G47A, D653T, R632K, G884 216 G47A, D653T, R632T, G884 217 G47A, D653T, P657W, R632K, G884 218 G47A, D653T, P657W, R632T, G884 219 G47A, D653T, P657R, R632K, G884 220 G47A, D653T, P657R, R632T, G884 221 G47A, D653T, P657A, R632K, G884 222 G47A, D653T, P657A, R632T, G884 223 G47A, D653K, R632K, G884 224 G47A, D653K, R632T, G884 225 G47A, D653K, P657W, R632K, G884 226 G47A, D653K, P657W, R632T, G884 227 G47A, D653K, P657R, R632K, G884 228 G47A, D653K, P657R, R632T, G884 229 G47A, D653K, P657A, R632K, G884 230 G47A, D653K, P657A, R632T, G884 231 G47A, F88OY, G884 232 G47A, F88OY, G884S 233 G47A, F88OY, G884T 234 Substitutions and / or C-terminal Modification SEQ ID NO: G47A, F88OY, G884P 235 E350W, D351V 236 E350W, K387N 237 E350W, D653T 238 D351V, K387N 239 D351V, D653T 240 K387N, D653T 241 Applications The RNA transcripts produced according to the present disclosure include mRNA (including modified mRNA and / or unmodified RNA), IncRNA, self-replicating RNA, circular RNA, CRISPR guide RNA, and the like. In embodiments, the RNA is RNA (e.g., mRNA or selfreplicating RNA) that encodes a polypeptide (e.g., a therapeutic polypeptide). Thus, the RNA transcripts produced using RNA polymerase variants of the present disclosure may be used in a myriad of applications. For example, the RNA transcripts may be used to produce polypeptides of interest, e.g., therapeutic proteins, vaccine antigen, and the like. In some embodiments, the RNA transcripts are therapeutic RNAs. A therapeutic mRNA is an mRNA that encodes a therapeutic protein (the term ‘protein’ encompasses peptides). Therapeutic proteins mediate a variety of effects in a host cell or in a subject to treat a disease or ameliorate the signs and symptoms of a disease. For example, a therapeutic protein can replace a protein that is deficient or abnormal, augment the function of an endogenous protein, provide a novel function to a cell (e.g., inhibit or activate an endogenous cellular activity, or act as a delivery agent for another therapeutic compound (e.g., an antibody-drug conjugate). Therapeutic mRNA may be useful for the treatment of the following diseases and conditions: bacterial infections, viral infections, parasitic infections, cell proliferation disorders, genetic disorders, and autoimmune disorders. Other diseases and conditions are encompassed herein. A protein of interest encoded by an mRNA as provided herein can be essentially any protein. In some embodiments, the therapeutic protein is a cytokine, a growth factor, an antibody or a fusion protein. Non-limiting examples of therapeutic proteins include blood factors (such as Factor VIII and Factor VII), complement factors, Low Density Lipoprotein Receptor (LDLR) and MUTI. Non-limiting examples of cytokines include interleukins, interferons, chemokines, lymphokines and the like. Non-limiting examples of growth factors include erythropoietin, EGFs, PDGFs, FGFs, TGFs, IGFs, TNFs, CSFs, MCSFs, GMCSFs and the like. Non-limiting examples of antibodies include adalimumab, infliximab, rituximab, ipilimumab, tocilizumab, canakinumab, itolizumab, tralokinumab. Non-limiting examples of fusion proteins include, for example, etanercept, abatacept and belatacept. In some embodiments, the protein of interest is human erythropoietin, LDLR (for use in inhibiting cholesterol), or MUTI (for use in the treatment of methylmalonic acidemia (MMA)). In other embodiments, the protein of interest encoded by the mRNA is a therapeutic antibody, including but not limited to the antibodies listed above. A RNA transcript produced using a RNA polymerase variant as disclosed herein may encode one or more biologies. A biologic is a polypeptide-based molecule that may be used to treat, cure, mitigate, prevent, or diagnose a serious or life-threatening disease or medical condition. Biologies include, but are not limited to, allergenic extracts (e.g. for allergy shots and tests), blood components, gene therapy products, human tissue or cellular products used in transplantation, vaccines, monoclonal antibodies, cytokines, growth factors, enzymes, thrombolytics, and immunomodulators, among others. One or more biologies currently being marketed or in development may be encoded by the RNA of the present invention. While not wishing to be bound by theory, it is believed that incorporation of the encoding polynucleotides of a known biologic into the RNA of the present disclosure will result in improved therapeutic efficacy due at least in part to the specificity, purity and / or selectivity of the construct designs. A RNA transcript produced using a RNA polymerase variant as disclosed herein may encode one or more antibodies. The term “antibody” includes monoclonal antibodies (including full length antibodies which have an immunoglobulin Fc region), antibody compositions with polyepitopic specificity, multispecific antibodies (e.g., bispecific antibodies, diabodies, and single-chain molecules), as well as antibody fragments. The term “immunoglobulin” (Ig) is used interchangeably with "antibody" herein. A monoclonal antibody is an antibody obtained from a population of substantially homogeneous antibodies, i.e., the individual antibodies comprising the population are identical except for possible naturally occurring mutations and / or posttranslation modifications (e.g., isomerizations, amidations) that may be present in minor amounts. Monoclonal antibodies are highly specific, being directed against a single antigenic site. Monoclonal antibodies specifically include chimeric antibodies (immunoglobulins) in which a portion of the heavy and / or light chain is identical with or homologous to corresponding sequences in antibodies derived from a particular species or belonging to a particular antibody class or subclass, while the remainder of the chain(s) is(are) identical with or homologous to corresponding sequences in antibodies derived from another species or belonging to another antibody class or subclass, as well as fragments of such antibodies, so long as they exhibit the desired biological activity. Chimeric antibodies include, but are not limited to, “primatized” antibodies comprising variable domain antigen-binding sequences derived from a non-human primate (e.g.. Old World Monkey, Ape etc.) and human constant region sequences. Antibodies encoded in the RNA of the present disclosure may be utilized to treat conditions or diseases in many therapeutic areas such as, but not limited to, blood, cardiovascular, CNS, poisoning (including antivenoms), dermatology, endocrinology, gastrointestinal, medical imaging, musculoskeletal, oncology, immunology, respiratory, sensory and anti-infective. A RNA transcript produced using a RNA polymerase variant as disclosed herein may encode one or more vaccine antigens. A vaccine antigen is a biological preparation that improves immunity to a particular disease or infectious agent. One or more vaccine antigens currently being marketed or in development may be encoded by the RNA of the present disclosure. Vaccine antigens encoded in the RNA may be utilized to treat conditions or diseases in many therapeutic areas such as, but not limited to, cancer, allergy and infectious disease. In some embodiments, a cancer vaccine may be a personalized cancer vaccine in the form of a concatemer or individual RNAs encoding peptide epitopes or a combination thereof. A RNA transcript produced using a RNA polymerase variant as disclosed herein may be designed to encode on or more antimicrobial peptides (AMP) or antiviral peptides (AVP). AMPs and AVPs have been isolated and described from a wide range of animals such as, but not limited to, microorganisms, invertebrates, plants, amphibians, birds, fish, and mammals. The anti-microbial polypeptides may block cell fusion and / or viral entry by one or more enveloped viruses (e.g., HIV, HCV). For example, the anti-microbial polypeptide can comprise or consist of a synthetic peptide corresponding to a region, e.g., a consecutive sequence of at least about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, or 60 amino acids of the transmembrane subunit of a viral envelope protein, e.g., HIV-1 gpl20 or gp41. The amino acid and nucleotide sequences of HIV-1 gpl20 or gp41 are described in, e.g., Kuiken et al., (2008). "HIV Sequence Compendium," Los Alamos National Laboratory. In some embodiments, RNA transcripts are used as radiolabeled RNA probes. In some embodiments, RNA transcripts are used for non-isotopic RNA labeling. In some embodiments, RNA transcripts are used as guide RNA (gRNA) for gene targeting. In some embodiments, RNA transcripts (e.g., mRNA) are used for in vitro translation and micro injection. In some embodiments, RNA transcripts are used for RNA structure, processing and catalysis studies. In some embodiments, RNA transcripts are used for RNA amplification. In some embodiments, RNA transcripts are used as anti-sense RNA for gene expression experiment. Other applications are encompassed by the present disclosure. Additional Embodiments: Additional embodiments of the present disclosure are encompassed by the following numbered paragraphs: 1. A ribonucleic acid (RNA) polymerase variant comprising a RNA polymerase that comprises: (a) an amino acid substitution at a binding site residue for de novo RNA synthesis; and (b) an amino acid modification that causes increased transcription efficiency, relative to wild-type RNA polymerase. 2. The RNA polymerase variant of paragraph 1, wherein the amino acid modification causes a loop structure of the RNA polymerase variant to undergo a conformational change to a helix structure as the RNA polymerase variant transitions from an initiation complex to an elongation complex. 3. The RNA polymerase variant of paragraph 2, wherein the amino acid modification is an amino acid substitution at position 47, relative to the wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. 4. The RNA polymerase variant of paragraph 3, wherein the amino acid substitution at position 47 is G47A. 5. The RNA polymerase variant of any one of paragraphs 1-4, wherein the amino acid modification comprises an additional C-terminal amino acid, relative to the wild-type RNA polymerase. 6. The RNA polymerase variant of paragraph 5, wherein the additional C-terminal amino acid is glycine. 7. The RNA polymerase variant of any one of paragraphs 1-6, wherein the amino acid substitution at a binding site residue causes at least one of the following benefits, relative to the wild-type RNA polymerase: (i) increased transcription efficiency, (ii) increased co-transcriptional capping efficiency; (iii) increased yield of RNA at 1 / 2 concentration of a cap analog; (iv) improved 3’ homogeneity of RNA at 1 / 2 concentration of a cap analog; (v) improved fidelity of transcription; and / or (vi) lower amount of dsRNA contamination. 8. The polymerase variant of any one of paragraphs 1-6, wherein the amino acid substitution at a binding site residue causes at least one of the following benefits, relative to the amino acid modification of (b): (i) increased transcription efficiency, (ii) increased co-transcriptional capping efficiency; (iii) increased yield of RNA at 1 / 2 concentration of a cap analog; (iv) improved 3’ homogeneity of RNA at 1 / 2 concentration of a cap analog; (v) improved fidelity of transcription; and / or (vi) lower amount of dsRNA contamination. 9. The RNA polymerase variant of any one of paragraphs 1-8, wherein the amino acid substitution at the binding site residue is a substitution at a position selected from positions 350, 351, 387, 394, 425, 427, 437, 441, 506, 628, 632, 653, 657, 811, and 880, relative to the wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. 10. A RNA polymerase variant comprising a RNA polymerase that comprises: (a) an amino acid substitution at a position selected from positions 350, 351, 387, 394, 425,427,437,441,506,628,632,653,657, 811,and 880; and (b) an additional amino acid substitution and / or an amino acid modification at the C-terminal end, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. 11. The RNA polymerase variant of paragraph 10 comprising the additional amino acid substitution of (b). 12. The RNA polymerase variant of paragraph 11, wherein the additional amino acid substitution of (b) is at position 47. 13. The RNA polymerase variant of paragraph 12, wherein the additional amino acid substitution at position 47 is G47A. 14. The RNA polymerase variant of any one of paragraphs 10-13 comprising the amino acid modification at the C-terminal end. 15 The RNA polymerase variant of paragraph 14, wherein the amino acid modification at the C-terminal end comprises an additional C-terminal amino acid. 16. The RNA polymerase variant of paragraph 15, wherein the additional C-terminal amino acid is selected from glycine, serine, alanine, proline, and threonine. 17. The RNA polymerase variant of paragraph 16, wherein the additional C-terminal amino acid is glycine. 18. The RNA polymerase variant of paragraph 16, wherein the additional C-terminal amino acid is alanine. 19. The RNA polymerase variant of paragraph 17 or 18 comprising a RNA polymerase that comprises (a) an amino acid substitution at a position selected from positions 350, 351, 387, 394, 425,427,437,441,506,628,632,653,657,811,and 880; (b) an additional amino acid substitution; and (c) an amino acid modification at the C-terminal end, relative to a wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. 20. The RNA polymerase variant of paragraph 19, wherein the additional amino acid substitution is at position 47. 21. The RNA polymerase variant of paragraph 20, wherein the additional amino acid substitution at position 47 is G47A. 22. The RNA polymerase variant of any one of paragraphs 19-21, wherein the amino acid modification at the C-terminal end comprises an additional C-terminal amino acid. 23. The RNA polymerase variant of paragraph 22, wherein the additional C-terminal amino acid is selected from glycine, serine, alanine, proline, glutamine, and threonine. 24. The RNA polymerase variant of paragraph 23, wherein the additional C-terminal amino acid is glycine. 25. The RNA polymerase variant of any one of paragraphs 1-24, wherein the additional amino acid substitution of (a) is at a position selected from position 387, 350, 351, 506, 628, 653, and 657, relative to the wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. 26. The RNA polymerase variant of paragraph 25, wherein the additional amino acid substitution is selected from K387S, K387H, and K387N. 27. The RNA polymerase variant of paragraph 25, wherein the additional amino acid substitution is selected from E350K, E350N, E350A, and E350W. 28. The RNA polymerase variant of paragraph 25, wherein the additional amino acid substitution is D351V. 29. The RNA polymerase variant of paragraph 25, wherein the additional amino acid substitution is D506W. 30. The RNA polymerase variant of paragraph 25, wherein the additional amino acid substitution is S628W. 31. The RNA polymerase variant of paragraph 25, wherein the additional amino acid substitution is D653W. 32. The RNA polymerase variant of paragraph 25, wherein the additional amino acid substitution is P657W. 33. The RNA polymerase variant of any one of paragraphs 1-24, wherein the additional amino acid substitution of (a) is at a position selected from position 350, 351, 387, and 437, relative to the wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. 34. The RNA polymerase variant of paragraph 33, wherein the additional amino acid substitution of (a) is at position 350, and the additional amino acid substitution at position 350 is selected from E350R, E350K, E350D, E350Q, E350N, E350T, E350S, E350C, E350G, E350A, E350V, E350L, E350I, E350P, E350Y, E350W, and E350F. 35. The RNA polymerase variant of paragraph 33, wherein the additional amino acid substitution of (a) is at position 351, and the additional amino acid substitution at position 350 is selected from D351R, D351K, D351Q, D351T, D351S, D351C, D351V, D351L, D351I, D351M, D351P, D351Y, and D351W. 36. The RNA polymerase variant of paragraph 33, wherein the additional amino acid substitution of (a) is at position 387, and the additional amino acid substitution at position 387 is selected from K387R, K387H, K387T, K387S, K387V, K387L, K387I, and K387M. 37. The RNA polymerase variant of paragraph 33, wherein the additional amino acid substitution of (a) is at position 437, and the additional amino acid substitution at position 437 is selected from N437Q, N437T, N437S, N437G, and N437F. 38. The RNA polymerase variant of paragraph 22, wherein the additional C-terminal amino acid is serine or alanine. 39. The RNA polymerase variant of paragraph 33, wherein the additional amino acid substitution of (a) is at position 350, and the additional amino acid substitution at position 350 is selected from E350N, E350C, E350G, E350Y, E350W, and E350F. 40. The RNA polymerase variant of paragraph 33, wherein the additional amino acid substitution of (a) is at position 351, and the additional amino acid substitution at position 351 is selected from D351R, D351S, D351L, D351M, and D351Y. 41. The RNA polymerase variant of paragraph 33, wherein the additional amino acid substitution of (a) is at position 387, and the additional amino acid substitution at position 387 is selected from K387R, K387T, K387L, and K387M. 42. The RNA polymerase variant of paragraph 33, wherein the additional amino acid substitution of (a) is at position 437, and the additional amino acid substitution at position 437 is selected from N437R, N437K, N437H, N437T, N437V, N437I, and N437W. 43. The RNA polymerase variant of paragraph 22, wherein the additional C-terminal amino acid is glutamine, threonine, or proline. 44. The RNA polymerase variant of any one of paragraphs 1-24, wherein the additional amino acid substitution of (a) is at a position selected from position 350, 351, 387, 437, 441, 632, and 880, relative to the wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. 45. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 350, and the additional amino acid substitution at position 350 is selected from E350R, E350K, E350D, E350Q, E350N, E350T, E350S, E350C, E350G, E350A, E350V, E350L, E350I, E350Y, E350W, and E350F. 46. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 351, and the additional amino acid substitution at position 351 is selected from D351R, D351K, D351Q, D351T, D351C, D351V, D351L, D351M, and D351W. 47. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 387, and the additional amino acid substitution at position 387 is selected from K387H, K387E, K387N, K387T, K387S, K387G, K387A, K387Y, K387W, and K387F. 48. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 437, and the additional amino acid substitution at position 437 is selected from N437T, N437I, N437Y, N437W, and N437F. 49. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 444, and the additional amino acid substitution at position 444 is K444R. 50. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 632, and the additional amino acid substitution at position 632 is selected from R632K and R632T. 51. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 880, and the additional amino acid substitution at position 880 is F88OY. 52. The RNA polymerase variant of paragraph 22, wherein the additional C-terminal amino acid is glutamine, threonine, and proline. 53. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 350, and the additional amino acid substitution at position 350 is selected from E350K, E350N, E350A, and E350W. 54. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 351, and the additional amino acid substitution at position 351 is D351V. 55. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 387, and the additional amino acid substitution at position 387 is selected from K387H, K387N, and K387S. 56. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 437, and the additional amino acid substitution at position 437 is selected from N437T, N437I, N437Y, and N437F. 57. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 444, and the additional amino acid substitution at position 444 is selected from K444R. 58. The RNA polymerase variant of paragraph 44, wherein the additional amino acid substitution of (a) is at position 880, and the additional amino acid substitution at position 880 is F88OY. 59. The RNA polymerase variant of paragraph 22, wherein the additional C-terminal amino acid is threonine, serine, alanine, and proline. 60. A RNA polymerase variant comprising a RNA polymerase that comprises: (a) an amino acid substitution at positions 350, 351, and 387; and (b) an additional amino acid substitution and / or an amino acid modification at the C-terminal end, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. 61. The RNA polymerase variant of paragraph 60, wherein: the additional amino acid substitution at position 350 is selected from E350A, E350K, E350N, and E350W; the additional amino acid substitution at position 351 is D351V; and / or the additional amino acid substitution at position 387 is selected from K387S, K387H, and K387N. 62. A RNA polymerase variant comprising a RNA polymerase that comprises: (a) an amino acid substitution at positions 437 and 441; and (b) an additional amino acid substitution and / or an amino acid modification at the C-terminal end, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. 63. The RNA polymerase variant of paragraph 62, wherein: the additional amino acid substitution at position 437 is selected from N437T, N437Y, N437I, and N437F; and / or the additional amino acid substitution at position 441 is K441R. 64. A RNA polymerase variant comprising a RNA polymerase that comprises: (a) an amino acid substitution at positions 880; and (b) an amino acid modification at the C-terminal end, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. 65. The RNA polymerase variant of paragraph 64, wherein: the additional amino acid substitution at position 880 is F88OY; and / or the amino acid modification at the C-terminal end is an additional amino acid selected from alanine, serine, threonine, and proline. 66. A RNA polymerase variant comprising a RNA polymerase that comprises: (a) an amino acid substitution at positions 632, 653, and 657; and (b) an additional amino acid substitution and / or an amino acid modification at the C-terminal end, relative to wild-type RNA polymerase, wherein the wild-type RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. 67. The RNA polymerase variant of paragraph 66, wherein: the additional amino acid substitution at position 632 is selected from R632K and R632T; the additional amino acid substitution at position 653 is selected from D653T and D653K; and / or. the additional amino acid substitution at position 657 is selected from P657W, P657R, or P657A. 68. The RNA polymerase variant of any one of paragraphs 60-67 comprising the additional amino acid substitution of (b). 69. The RNA polymerase variant of paragraph 68, wherein the additional amino acid substitution of (b) is at position 47. 70. The RNA polymerase variant of paragraph 69, wherein the additional amino acid substitution of (b) at position 47 is G47A. 71. The RNA polymerase variant of any one of paragraphs 60-70 comprising the amino acid modification at the C-terminal end. 72. The RNA polymerase variant of paragraph 71, wherein the amino acid modification at the C-terminal end comprises an additional C-terminal amino acid. 73. The RNA polymerase variant of paragraph 72, wherein the additional C-terminal amino acid is glycine. 74. The RNA polymerase variant of any one of paragraphs 1-73 comprising an amino acid sequence having at least 90% identity to the wild-type RNA polymerase, wherein the wildtype RNA polymerase comprises the amino acid sequence of SEQ ID NO: 1. 75. A method comprising producing a ribonucleic acid (RNA) transcript in an in vitro transcription reaction that comprises a polynucleotide template, nucleoside triphosphates, a cap analog, and a RNA polymerase comprising at least one mutation relative to a wild-type RNA polymerase, wherein the reaction comprises a concentration of the cap analog that is at least 5fold lower than a concentration of the cap analog required to produce an equivalent amount of RNA transcript using wild-type RNA polymerase, optionally wherein the wild-type RNA polymerase is wild-type T7 RNA polymerase. 76. The method of paragraph 75, wherein greater than 80% of the RNA transcript produced includes a functional cap. 77. The method of paragraph 75 or 76, wherein the RNA transcript produced has greater than a threshold 3’ homogeneity, wherein the threshold 3’ homogeneity is at least 50% 3’ homogeneity. 78. The method of any one of paragraph 75-77, wherein the RNA transcript produced has lower than a threshold quantity of dsRNA, wherein the threshold quantity of dsRNA is 5 ng dsRNA per 25 pg of mRNA. 79. A method comprising producing a RNA transcript in an in vitro transcription reaction that comprises a polynucleotide template, nucleoside triphosphates, and the RNA polymerase variant of any one of paragraphs 1-74. 80. A method comprising producing a RNA transcript in an in vitro transcription reaction that comprises a polynucleotide template, nucleoside triphosphates, a cap analog, and the RNA polymerase variant of any one of paragraphs 1-72. 81. The method of paragraph 79 or 80, wherein the nucleoside triphosphates comprise unmodified or modified ATP, modified or unmodified UTP, modified or unmodified GTP, and / or modified or unmodified CTP. 82. The method of paragraph 80 or 81, wherein the reaction comprises a concentration of the cap analog that is at least 2-fold lower, at least 5-fold lower, or at least 10fold lower than a concentration of the cap analog required to produce an equivalent amount of RNA transcript using the wild-type RNA polymerase. 83. The method of any one of paragraphs 80-82, wherein greater than 80%, greater than 85%, greater than 90%, or greater than 95% of the RNA transcript produced includes a functional cap. 84. The method of any one of paragraphs 80-83, wherein the nucleoside triphosphates and cap analog are present in the reaction at equimolar concentrations. 85. The method of any one of paragraphs 80-84, wherein a molar ratio of cap analog to nucleoside triphosphates in the reaction is greater than 1:1 or equal to 1:1. 86. The method of any one of paragraphs 80-85, wherein the cap analog is a dinucleotide cap, a trinucleotide cap, or a tetranucleotide cap. 87. The method of any one of paragraphs 80-86, wherein the cap analog is a natural cap analog or a synthetic cap analog. 88. The method of paragraph 86 or 87, wherein the cap analog is a trinucleotide cap comprising a sequence selected from the following sequences: GAA, GAC, GAG, GAU, GCA, GCC, GCG, GCU, GGA, GGC, GGG, GGU, GUA, GUC, GUG, and GUU. 89. The method of paragraph 88, wherein the trinucleotide cap comprises a sequence selected from the following sequences: GAG, GCG, GUG, and GGG. 90. The method of paragraph 89, wherein the trinucleotide cap comprises sequence GAG. 91. The method of paragraph 90, wherein the trinucleotide cap comprises a sequence selected from the following sequences: (a) m7GpppApA, m7GpppApC, m7GpppApG, m7GpppApU, m7GpppCpA, m7GpppCpC, m7GpppCpG, m7GpppCpU, m7GpppGpA, m7GpppGpC, m7GpppGpG, m7GpppGpU, m7GpppUpA, m7GpppUpC, m7GpppUpG, and m7GpppUpU; (b) m7G3'OMepppApA, m7G3'OMepppApC, m7G3'OMepppApG, m'GsWepppApU. m7G3'OMePPpCpA, m7G3'OMePPpCpC, m7G3'OMePPpCpG, m7G3'OMePPpCpU, m7G3'OMePPpGpA, m7G3'OMePPpGpC, m7G3'OMePPpGpG, m7G3'OMepppGpU, m7G3'OMePPpUpA, m7G3'OMepppUpC, m7G3'OMePPpUpG, and m7G3'OMePPpUpU; (c) m7G3'OMepppA2'OMepA, m7G3'OMepppA2'OMepC, m7G3'OMepppA2'OMepG, m7G3'OMePPpA2'OMepU, m7G3'OMePPpC2'OMepA, m7G3'OMePPpC2'OMepC, m7G3'OMePPpC2'OMepG, m7G3'OMePPpC2'OMepU, m7G3'OMePPpG2'OMepA, m7G3'OMepppG2'OMepC, m7G3'OMepppG2'OMepG, m7G3'OMePPpG2'OMepU, m7G3'OMePPpU2'OMepA, m7G3'OMepppU2'OMepC, m7G3'OMepppU2'OMepG, and m7G3'OMepppU2'OMepU; or (d) m7GpppA2'oMepA, m7GpppA2'oMEpC, m7GpppA2'oMepG, m7GpppA2'oMepU, m7GpppC2'OMepA, m7GpppC2'OMepC, m7GpppC2'OMepG, m7GpppC2'OMepU, m7GpppG2'OMepA, m7GpppG2'OMepC, m7GpppG2'OMepG, m7GpppG2'OMepU, m7GpppU2'OMepA, m7GpppU2'OMepC, m7GpppU2'OMepG, and m7GpppU2'OMepU. 92. The method of paragraph 91, wherein the trinucleotide cap comprises GpppA2'omepG. 93. The method of any one of paragraphs 75-92, wherein the polynucleotide template includes a 2'-deoxythymidine residue or a 2'-deoxycytidine residue at template position +1. 94. The method of any one of paragraphs 75-93, wherein the RNA transcript produced, when delivered to cells, optionally in unpurified form, stimulates a cytokine response that is at least 50% lower relative to RNA produced using wild-type RNA polymerase. 95. The method of any one of paragraphs 75-94, wherein the concentration of doublestranded RNA (dsRNA) transcript produced is at least 50% lower relative to dsRNA transcript produced using wild-type RNA polymerase. 96. The method of any one of paragraphs 75-95, wherein less than 50%, less than 25%, or less than 10% of the RNA transcript produced is dsRNA. 97. The method of any one of paragraphs 75-96, wherein less than 30% or less than 20% of the RNA transcripts produced exhibit 3' heterogeneity. 98. The method of any one of paragraphs 75-97, wherein less than 50%, less than 25%, or less than 10% of the RNA transcript produced is run-on RNA transcript. 99. The method of any one of paragraphs 75-98, wherein the amount of full-length RNA transcript produced is at least 15 times greater than the amount of the polynucleotide template. 100. The method of any one of paragraphs 75-99, wherein the ratio of dsRNATull-length RNA transcript produced is less than 1:1. 101. The method of any one of paragraphs 75-100, wherein the RNA transcript produced has less than 1 mutation per 100 nucleotides relative to the polynucleotide template. 102. A nucleic acid encoding the RNA polymerase variant of any one of paragraphs 174. 103. A composition comprising the RNA polymerase variant of any one of paragraphs 1-74 and optionally nucleoside triphosphates. 104. A kit comprising the RNA polymerase variant of any one of paragraphs 1-74 and an in vitro transcription (IVT) reagent. 105. A ribonucleic acid (RNA), optionally a messenger RNA (mRNA), produced by the method of any one of paragraphs 75-104. 106. A lipid nanoparticle comprising the RNA of paragraph 103, optionally wherein the lipid nanoparticle comprises a molar ratio of 20-60% ionizable amino lipid, 5-25% noncationic lipid, 25-55% sterol, and 0.5-15% PEG-modified lipid. 107. A RNA polymerase variant derived from a starting RNA polymerase that has an amino acid modification at position G47 and an additional C-terminal amino acid relative to a wild type amino acid sequence of T7 RNA polymerase comprising the sequence of SEQ ID NO: 1, wherein the variant comprises at least one substitution that affects first nucleotide binding to the D-site within the RNA polymerase variant as it is in the conformational state for de novo initiation of RNA synthesis, and wherein the amino acid substitution causes at least one of the following benefits relative to the starting RNA polymerase: (i) increased transcription efficiency, (ii) increased co-transcriptional capping efficiency; (iii) increased yield of RNA; (iv) improved 3’ homogeneity of RNA transcripts; (v) improved fidelity of transcription; and (vi) lower amounts of dsRNA in the reaction mixture. 108. A RNA polymerase variant comprising the amino acid sequence of any one of SEQ ID NOS: 3-14, 45-48, or 242-247, wherein X is any amino acid selected from R, K, H, E, D, Q, N, T, S, C, G, A, V, L, I, M, P, Y, W, and F. 109. The RNA polymerase of paragraph 108 comprising the amino acid sequence of SEQ ID NO: 47. 110. The RNA polymerase of paragraph 109, wherein X is W. 111. The RNA polymerase variant of any one of paragraphs 108-110 further comprising a G47A substitution. 112. The RNA polymerase variant of any one of paragraphs 108-111 further comprising an additional C-terminal amino acid. 113. The RNA polymerase variant of paragraph 112, wherein the additional C-terminal amino acid is glycine. 114. A RNA polymerase variant comprising the amino acid sequence of any one of SEQ ID NOS: 61-241. 115. A nucleic acid encoding the RNA polymerase variant of paragraph 114. 116. A method comprising producing a RNA transcript in an in vitro transcription reaction that comprises a polynucleotide template, nucleoside triphosphates, and the RNA polymerase variant of paragraph 114. 117. A method comprising producing a RNA transcript in an in vitro transcription reaction that comprises a polynucleotide template, nucleoside triphosphates, a cap analog, and the RNA polymerase variant of paragraph 114. 118. A RNA polymerase variant comprising a RNA polymerase that comprises: (a)    an amino acid substitution at position E350, K387, N437, F880, or D653; (b)    an amino acid substitution at position G47; and / or (c)    an amino acid modification at the C-terminal end, relative to a wild-type RNA polymerase comprising the amino acid sequence of SEQ ID NO: 1. 119. The RNA polymerase of paragraph 118, wherein the amino acid substitution of (a) is selected from the group consisting of E350N, K387N, N437F, F88OY, and D653W. 120. The RNA polymerase variant of paragraph 119, wherein the amino acid substitution of (a) is D653W. 121. The RNA polymerase variant of any one of paragraphs 118-120, wherein the amino acid substitution at position G47 is G47A. 122. The RNA polymerase variant of any one of paragraphs 118-121, wherein the amino acid modification at the C-terminal end is an additional glycine, an additional alanine, an additional threonine, or an additional proline. 123. A RNA polymerase variant comprising a RNA polymerase that comprises amino acid substitution at two of the positions selected from the group consisting of E350, D351, K387, N437, K441, D506, R632, D653, S628, P657, and F88O, relative to a wild-type RNA polymerase comprising the amino acid sequence of SEQ ID NO: 1. 124. The RNA polymerase variant of paragraph 123 comprising amino acid substiutions at E350 and D351. 125. The RNA polymerase variant of paragraph 123 comprising amino acid substiutions at E350 and K387. 126. The RNA polymerase variant of paragraph 123 comprising amino acid substiutions at K387 and D653. 127. The RNA polymerase variant of any one of paragraphs 123-125, wherein the amino acid substitution at position E350 is E350W, E350A, E350K, or E350N. 128. The RNA polymerase variant of paragraph 123 or 124, wherein the amino acid substitution at position D351 is D351V. 129. The RNA polymerase variant of any one of paragraphs 123, 125, or 126, wherein the amino acid substitution at position K387 is K387N, K387S, or K387H. 130. The RNA polymerase variant of paragraph 123 or 126, wherein the amino acid substitution at position D653 is D653T or D653K. 131. A method comprising producing a RNA transcript in an in vitro transcription reaction that comprises a polynucleotide template, nucleoside triphosphates, a cap analog, and the RNA polymerase variant of any one of the preceding paragraphs, wherein the cap analog is a trinucleotide cap analog or a tetranucleotide cap analog. 132. The method of any one of the preceding paragraphs, wherein the cap analog is a trinucleotide cap analog that comprises GAG. 133. The method of paragraph 132, wherein the GAG cap analog is selected from: (i); (ii); or 134. The method of any one of the preceding paragraphs, wherein the cap analog is a tetranucleotide cap analog that comprises GGAG. 135. The method of paragraph 134, wherein the tetranucleotide cap analog is selected from: 136. The method of any one of the preceding paragraphs, wherein greater than 80%, greater than 85%, greater than 90%, or greater than 95% of the RNA transcript produced includes a cap analog. 137. The method of any one of the preceding paragraphs, wherein the method produces at least 50%, at least 60%, or at least 75% more RNA transcript comprising a cap analog than a control in vitro transcription reaction comprising a wild-type RNA polymerase of SEQ ID NO: 1. 138. The method of any one of the preceding paragraphs, wherein a molar ratio of cap analog to nucleoside triphosphates in the reaction is between 1:10 and 1:1. 139. The method of any one of the preceding paragraphs, wherein less than 1%, less than 0.5%, or less than 0.1% of the RNA transcript produced is double-stranded RNA (dsRNA). 140. The method of any one of the preceding paragraphs, wherein the reaction produces at least 5 mg / mL, at least 6 mg / mL, at least 7 mg / mL, at least 8 mg / mL, at least 9 mg / mL, or at least 10 mg / mL of RNA transcript. 141. The method of any one of the preceding paragraphs, wherein at least 85%, at least 90%, or at least 95% of RNA transcript produced is a full-length RNA transcript. 142. The method of any one of the preceding paragraphs, wherein the method produces at least 10%, at least 25%, or at least 50% more RNA transcript comprising a cap analog than a control in vitro transcription reaction involving a control RNA polymerase variant, wherein the control RNA polymerase variant is derived from SEQ ID NO:1 and comprises a G47A mutation and an additional glycine at the C-terminal end. 143. A method comprising producing a RNA transcript in an in vitro transcription reaction that comprises a polynucleotide template, nucleoside triphosphates, a cap analog, and a wild-type RNA polymerase, wherein the cap analog is a trinucleotide cap analog or a tetranucleotide cap analog. 144. The method of paragraph 143, wherein the wild-type RNA polymerase comprises an amino acid sequence of SEQ ID NO: 1. 145.   The method of paragraph 143 or 144, wherein the cap analog is a tetranucleotide cap analog that comprises GGAG. 146. The method of any one of paragraphs 143-145, wherein the tetranucleotide cap analog is selected from: Wild-type T7 RNA Polymerase MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRKMFERQLKAGEVADNAAAKPLITTL LPKMIARINDWFEEVKAKRGKRPTAFQFLQEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRI RDLEAKHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHVGVRCIEMLIESTGMVSLHR QNAGWGQDSETIELAPEYAEAIATRAGALAGISPMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRY EDVYMPEVYKAINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNPEALTAWKRAAAAVY RKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRGRVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKI HGANCAGVDKVPFPERIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNCSLPLAFDGS CSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQADAINGTDNEWTVTDENTGEISEKVKLGTKAL AGQWLAYGVTRSVTKRSVMTLAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTWAAV EAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKPIQTRLNLMFLGQFRLQPTINTNKDSEID AHKQESGIAPNFVHSQDGSHLRKTWWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYD QFADQLHESQLDKMPALPAKGNLNLRDILESDFAFA (SEQ ID NO: 1) Control T7 RNA Polymerase Variant (G47A+C-terminal G) MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRKMFERQLKAGEVADNAAAKPLITTL LPKMIARINDWFEEVKAKRGKRPTAFQFLQEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRI RDLEAKHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHVGVRCIEMLIESTGMVSLHR QNAGWGQDSETIELAPEYAEAIATRAGALAGISPMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRY EDVYMPEVYKAINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNPEALTAWKRAAAAVY RKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRGRVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKI HGANCAGVDKVPFPERIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNCSLPLAFDGS CSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQADAINGTDNEWTVTDENTGEISEKVKLGTKAL AGQWLAYGVTRSVTKRSVMTLAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTWAAV EAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKPIQTRLNLMFLGQFRLQPTINTNKDSEID AHKQESGIAPNFVHSQDGSHLRKTWWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYD QFADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG (SEQ ID NO: 44) EXAMPLES Example 1. Production of RNA polymerases variants. RNA polymerase variants were generated with the substitutions shown in Tables 2-6. Table 2. RNA Polymerase Variants RNA Polymerase Variants Amino Acid Sequence SEQ ID NO For the amino acid sequences of SEQ ID NO: 2-14, 45-48, and 242-247, X may be any amino acid selected from R, K, H, E, D, Q, N, T, S, C, G, A, V, L, I, M, P, Y, W, and F. G47X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMXEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 2 E350X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVXDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 3 D351X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEXIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP 4 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA K387X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRXDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 5 R394X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSXRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTLQPALDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTLNTNKDSELDAHKQESGLAPNFVHSQDGSHLRKTV VWAHEKYGIESFALLHDSFGTLPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDLLESDFAFA 6 R425X MNTLNLAKNDFSDLELAALPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARLNDWFEEVKAKRGKRPTAFQFL QELKPEAVAYLTIKTTLACLTSADNTTVQAVASALGRALEDEARFGRLRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG XVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 7 Y427X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK 8 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVXAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA N437X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGXDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 9 K441X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTXGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 10 R632X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKXSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV 11 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA H811X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIXDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 12 F880X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDXAFA 13 884X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAX 14 D506X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP 45 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQXSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA S628X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRXVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 46 D653X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEXTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 47 P657X MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQXAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV 48 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA Table 3. Exemplary Single-Substitution Variants RNA Polymerase Variants Amino Acid Sequence SEQ ID NO G47A MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 15 E350K MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVKDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 16 E350N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVNDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV 17 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA E350A MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVADIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 18 E350W MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVWDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 19 D351V MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 20 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO K387S MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 21 K387H MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP EYAEAIATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRHDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTLQPALDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTLNTNKDSELDAHKQESGLAPNFVHSQDGSHLRKTV VWAHEKYGIESFALLHDSFGTLPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDLLESDFAFA 22 K387N MNTLNLAKNDFSDLELAALPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARLNDWFEEVKAKRGKRPTAFQFL QELKPEAVAYLTIKTTLACLTSADNTTVQAVASALGRALEDEARFGRLRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 23 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO D506W MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQWSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 49 S628W MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP EYAEAIATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE ISEKVKLGTKALAGQWLAYGVTRWVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 50 D653W MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEWTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 51 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO P657W MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMGEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQWAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 52 Table 4. Exemplary Multi-Substitution Variants RNA Polymerase Variants Amino Acid Sequence SEQ ID NO G47A E350K MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVKDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 24 G47A E350N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVNDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 25 G47A E350A MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA 26 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVADIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA G47A E350W MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVWDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 27 G47A D351V MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 28 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO G47A K387S MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 29 G47A K387H MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP EYAEAIATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRHDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTLQPALDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTLNTNKDSELDAHKQESGLAPNFVHSQDGSHLRKTV VWAHEKYGIESFALLHDSFGTLPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDLLESDFAFA 30 G47A K387N MNTLNLAKNDFSDLELAALPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARLNDWFEEVKAKRGKRPTAFQFL QELKPEAVAYLTIKTTLACLTSADNTTVQAVASALGRALEDEARFGRLRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 31 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO G47A D506W MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQWSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 53 G47A S628W MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP EYAEAIATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE ISEKVKLGTKALAGQWLAYGVTRWVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 54 G47A D653W MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEWTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 55 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO G47A P657W MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQWAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFA 56 Table 5. Exemplary Multi-Substitution + C-Terminal G Variants RNA Polymerase Variants Amino Acid Sequence SEQ ID NO G47A E350K C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVKDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 32 G47A E350N C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVNDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 33 G47A E350A MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL 34 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO C-Terminal G QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVADIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A E350W C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVWDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 35 G47A D351V C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 36 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO G47A K387S C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 37 G47A K387H C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP EYAEAIATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRHDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTLNTNKDSELDAHKQESGLAPNFVHSQDGSHLRKTV VWAHEKYGIESFALLHDSFGTLPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDLLESDFAFAG 38 G47A K387N C-Terminal G MNTLNLAKNDFSDLELAALPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARLNDWFEEVKAKRGKRPTAFQFL QELKPEAVAYLTIKTTLACLTSADNTTVQAVASALGRALEDEARFGRLRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 39 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO G47A D506W C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQWSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 57 G47A S628W C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP EYAEAIATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE ISEKVKLGTKALAGQWLAYGVTRWVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 58 G47A D653W C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEWTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 59 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO G47A P657W C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQWAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 60 Table 6.     Additional Multi-Substitution Variants RNA Polymerase Variants Amino Acid Sequence SEQ ID NO G47A E350Xb wherein Xi is A, K, N, or W D351V K387X2, wherein X2 is S, H, or N C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVXiVIPAIEREELPMKPEDIDMN PEALTAWKRAAAAVYRX2DKARKSRRISLEFMLEQANKFANHKAIWFPYNMDW RGRVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPF PERIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSY NCSLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEI LQADAINGTDNEWTVTDENTGEI SEKVKLGTKALAGQWLAYGVTRSVTKRSV MTLAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSV TWAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYK KPIQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRK TWWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFY DQFADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 40 G47A N437Xb wherein Xi is T, Y, I, or F K441R C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGXDMTRGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 41 G47A F880Y MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL 42 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO C-Terminal X, wherein X is A, S, T, or P QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDYAFAX G47A R632Xb wherein Xi is K or T D653X2, wherein Xj is T or K P657X3, wherein X3 is W, R, or A C-Terminal G MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKXiSVM TLAYGSKEFGFRQQVLEX2TIQX3AIDSGKGLMFTQPNQAAGYMAKLIWESVS VTWAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEY KKPIQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLR KTWWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADF YDQFADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 43 G47A, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 61 G47A, G884T MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ 62 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAT G47A, G884T, K387N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAT 63 G47A, G884S MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAS 64 G47A, G884S, K387N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAS 65 G47A, G884P MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA 66 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAP G47A, G884P, K387N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAP 67 G47A, D653W, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEWTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 68 G47A, D653W, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT 69 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO LAYGSKEFGFRQQVLEWTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, D653W, G884T MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEWTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAT 70 G47A, D653W, G884T, K387N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEWTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTLNTNKDSELDAHKQESGLAPNFVHSQDGSHLRKTV VWAHEKYGIESFALLHDSFGTLPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDLLESDFAFAT 71 G47A, D653W, G884S MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARLNDWFEEVKAKRGKRPTAFQFL QELKPEAVAYLTIKTTLACLTSADNTTVQAVASALGRALEDEARFGRLRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEWTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAS 72 G47A, D653W, G884S, K387N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV 73 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP EYAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEWTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAS G47A, D653W, G884P MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEWTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAP 74 G47A, D653W, G884P, K387N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEWTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAP 75 G47A, D653T, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLETTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV 76 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, D653T, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLETTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 77 G47A, D653T, G884T MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLETTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDLLESDFAFAT 78 G47A, D653T, G884T, K387N MNTLNLAKNDFSDLELAALPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARLNDWFEEVKAKRGKRPTAFQFL QELKPEAVAYLTIKTTLACLTSADNTTVQAVASALGRALEDEARFGRLRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLETTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAT 79 G47A, D653T, G884S MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS 80 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLETTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAS G47A, D653T, G884S, K387N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLETTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAS 81 G47A, D653T, G884P MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLETTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAP 82 G47A, D653T, G884P, K387N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLETTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP 83 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAP G47A, D653K, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEKTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 84 G47A, D653K, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEKTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDLLESDFAFAG 85 G47A, D653K, G884T MNTLNLAKNDFSDLELAALPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARLNDWFEEVKAKRGKRPTAFQFL QELKPEAVAYLTIKTTLACLTSADNTTVQAVASALGRALEDEARFGRLRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEKTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAT 86 G47A, D653K, G884T, K387N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK 87 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEKTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAT G47A, D653K, G884S MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEKTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAS 88 G47A, D653K, G884S, K387N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEKTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAS 89 G47A, D653K, G884P MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEKTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV 90 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAP G47A, D653K, G884P, K387N MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEKTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAP 91 G47A, K387S, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 92 G47A, K387H, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARLNDWFEEVKAKRGKRPTAFQFL QELKPEAVAYLTIKTTLACLTSADNTTVQAVASALGRALEDEARFGRLRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRHDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 93 G47A, E350A, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVADIPAIEREELPMKPEDIDMNP 94 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, E350A, K387S, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVADIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 95 G47A, E350A, K387H, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVADIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 96 G47A, E350A, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVADIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV 97 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, E350K, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVKDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 98 G47A, E350K, K387S, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVKDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 99 G47A, E350K, K387H, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QELKPEAVAYLTIKTTLACLTSADNTTVQAVASALGRALEDEARFGRLRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVKDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRHDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 100 G47A, E350K, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVKDIPAIEREELPMKPEDIDMNP 101 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, E350N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVNDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 102 G47A, E350N, K387S, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVNDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 103 G47A, E350N, K387H, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVNDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV 104 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, E350N, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVNDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 105 G47A, E350W, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVWDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 106 G47A, E350W, K387S, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QELKPEAVAYLTIKTTLACLTSADNTTVQAVASALGRALEDEARFGRLRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVWDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 107 G47A, E350W, K387H, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVWDIPAIEREELPMKPEDIDMNP 108 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO EALTAWKRAAAAVYRHDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, E350W, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVWDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRHDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 109 G47A, D351V, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 110 G47A, D351V, K387S, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV 111 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, D351V, K387H, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRHDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 112 G47A, D351V, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 113 G47A, D351V, E350A, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QELKPEAVAYLTIKTTLACLTSADNTTVQAVASALGRALEDEARFGRLRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVAVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRHDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 114 G47A, D351V, E350A, K387S, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVAVIPAIEREELPMKPEDIDMNP 115 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, D351V, E350A, K387H, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVAVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRHDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 116 G47A, D351V, E350A, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVAVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 117 G47A, D351V, E350K, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVKVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV 118 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, D351V, E350K, K387S, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVKVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 119 G47A, D351V, E350K, K387H, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVKVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRHDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 120 G47A, D351V, E350K, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVKVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 121 G47A, D351V, E350N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVNVIPAIEREELPMKPEDIDMNP 122 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, D351V, E350N, K387S, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVNVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 123 G47A, D351V, E350N, K387H, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVNVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 124 G47A, D351V, E350N, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVNVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV 125 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, D351V, E350W, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVWVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 126 G47A, D351V, E350W, K387S, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVWVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRSDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGE I SEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 127 G47A, D351V, E350W, K387H, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSLHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVWVIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRHDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 128 G47A, D351V, E350W, K387N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVWVIPAIEREELPMKPEDIDMNP 129 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO EALTAWKRAAAAVYRNDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEDTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, D653A, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEATIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 130 G47A, D653F, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEFTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 131 G47A, D653G, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEGTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV 132 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, D653H, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEHTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 133 G47A, D653I, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEITIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 134 G47A, D653L, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLELTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 135 G47A, D653M, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP 136 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEMTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, D653N, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLENTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 137 G47A, D653P, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEPTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 138 G47A, D653Q, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEQTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV 139 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, D653R, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRCIEMLIE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEAIATRAGALAGIS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLERTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 140 G47A, D653S, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E T L E LAP E YAEA L ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLESTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 141 G47A, D653V, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEVTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG 142 G47A, D653Y, G884 MNTINIAKNDFSDIELAAIPFNTLADHYGERLAREQLALEHESYEMAEARFRK MFERQLKAGEVADNAAAKPLITTLLPKMIARINDWFEEVKAKRGKRPTAFQFL QEIKPEAVAYITIKTTLACLTSADNTTVQAVASAIGRAIEDEARFGRIRDLEA KHFKKNVEEQLNKRVGHVYKKAFMQWEADMLSKGLLGGEAWSSWHKEDSIHV GVRC I EML IE S T GMVS LHRQNAGWGQD S E TIE LAP E YAEA I ATRAGALAG IS PMFQPCWPPKPWTGITGGGYWANGRRPLALVRTHSKKALMRYEDVYMPEVYK AINIAQNTAWKINKKVLAVANVITKWKHCPVEDIPAIEREELPMKPEDIDMNP 143 RNA Polymerase Variants Amino Acid Sequence SEQ ID NO EALTAWKRAAAAVYRKDKARKSRRISLEFMLEQANKFANHKAIWFPYNMDWRG RVYAVSMFNPQGNDMTKGLLTLAKGKPIGKEGYYWLKIHGANCAGVDKVPFPE RIKFIEENHENIMACAKSPLENTWWAEQDSPFCFLAFCFEYAGVQHHGLSYNC SLPLAFDGSCSGIQHFSAMLRDEVGGRAVNLLPSETVQDIYGIVAKKVNEILQ ADAINGTDNEWTVTDENTGEISEKVKLGTKALAGQWLAYGVTRSVTKRSVMT LAYGSKEFGFRQQVLEYTIQPAIDSGKGLMFTQPNQAAGYMAKLIWESVSVTV VAAVEAMNWLKSAAKLLAAEVKDKKTGEILRKRCAVHWVTPDGFPVWQEYKKP IQTRLNLMFLGQFRLQPTINTNKDSEIDAHKQESGIAPNFVHSQDGSHLRKTV VWAHEKYGIESFALIHDSFGTIPADAANLFKAVRETMVDTYESCDVLADFYDQ FADQLHESQLDKMPALPAKGNLNLRDILESDFAFAG G47A, P657W, G884 MNTINIAKNDFSDIE...

Claims

1. A ribonucleic acid (RNA) polymerase variant comprising a RNA polymerase thatcomprises an amino acid substitution at position E350 and D351, relative to a RNA polymerase comprising the amino acid sequence of SEQ ID NO: 1 or SEQ ID NO: 44 and has at least 95% identity to the amino acid sequences of SEQ ID NO: 1 or SEQ ID NO: 44.

2. The RNA polymerase variant of any one of claim 1, wherein the RNA polymerasecomprises an amino acid substitution at a position selected from the group consisting of K387, N437, K441, D506, D653, S628, P657, and F880.

3. The RNA polymerase variant of claims 1 or 2, wherein the RNA polymerase comprisesan amino acid substitution at R632.

4. The RNA polymerase variant of any one of claims 1-3, wherein the RNA polymerasecomprises at least 95% identity to the amino acid sequence of SEQ ID NO: 1.

5. The RNA polymerase variant of any one of claims 1-3, wherein the RNA polymerasevariant has at least 98% identity to the amino acid sequence of SEQ ID NO: 1.

6. The RNA polymerase variant of any one of claims 1-3, wherein the RNA polymerasevariant has the amino acid sequence of SEQ ID NO: 1 with the cited mutations.

7. The RNA polymerase variant of any one of claims 1-6, further comprising a C-terminalG.

8. The RNA polymerase variant of any one of claims 1-7, further comprising an amino acidsubstitution at position G47.

9. The RNA polymerase variant of claim 8, wherein the amino acid substitution at positionG47 is G47A.2020224103   26 Jun 202610. The RNA polymerase variant of claim 1, wherein the RNA polymerase comprises at least three, at least four, or at least five amino acid substitutions at positions selected from the group consisting of E350, D351, K387, N437, K441, D506, R632, D653, S628, P657, F880, and G884.

11. The RNA polymerase variant of claim 10, wherein the RNA polymerase comprises amino acid substitutions at positions selected from the group consisting of: E350 and K387; E350 and N437; E350 and K441; E350 and D506; E350 and R632; E350 and D653; E350 and S628; E350 and P657; E350 and F880; E350 and G884; D351 and K387, D351 and N437; D351 and K441; D351 and D506; D351 and R632; D351 and D653; D351 and S628; D351 and P657; D351 and F880; D351 and G884; K387 and N437; K387 and K441; K387 and D506; K387 and R632; K387 and D653; K387 and S628; K387 and P657; K387 and F880; and K387 and G884; N437 and K441; N437 and D506; N437 and R632; N437 and D653; N437 and S628; N437 and P657; N437 and F880; N437 and G884; K441 and D506; K441 and R632; K441 and D653;K441 and S628; K441 and P657; K441 and F880; K441 and G884; D506 and R632; D506 and D653; D506 and S628; D506 and P657; D506 and F880; D506 and G884; R632 and D653; R632 and S628; R632 and P657; R632 and F880; R632 and G884; D653 and S628; D653 and P657; D653 and F880; D653 and G884; S628 and P657; S628 and F880; S628 and G884; P657 and F880; P657 and G884; and F880 and G884.

12. The RNA polymerase variant of claim 11, wherein the RNA polymerase comprises amino acid substitutions at positions selected from the group consisting of: K387, D653, and G884; E350, D351, and K387; and D653, P657, and R632.

13. The RNA polymerase variant of any one of claims 1-12, wherein the amino acid substitution at E350 is selected from the group consisting of E350A, E350K, E350N, and E350W, optionally wherein the amino acid substitution at E350 is E350N.

14. The RNA polymerase variant of any one of claims 1-13, wherein the amino acid substitution at D351 is selected from D351C, D351I, D351K, D351L, D351M, D351P, D351Q, D351R, D351S, D351T, D351V, and D351W and optionally is D351V.2020224103   26 Jun 202615. The RNA polymerase variant of any one of claims 10-14, wherein the amino acid substitution at R632 is R632K or R632T.

16. The RNA polymerase variant of any one of claims 10-15, wherein the amino acid substitution at G884 is selected from the group consisting of G884A, G884S, G884T, and G884P.

17. A method comprising producing a mRNA in an in vitro transcription reaction that comprises a DNA template, nucleoside triphosphates, and the RNA polymerase variant of any one of claims 1-16.

18. The method of claim 17, wherein the reaction comprises a cap analog.

19. The method of claim 18, wherein the reaction comprises a concentration of the capanalog that is at least 5-fold lower than a concentration of the cap analog required to produce an equivalent amount of mRNA using a T7 RNA polymerase that comprises the amino acid sequence of SEQ ID NO: 44.

20. The method of any one of claims 18-19, wherein the cap analog and nucleoside triphosphates are present in the reaction at equimolar concentrations, or a molar ratio of cap analog to nucleoside triphosphates in the reaction is greater than 1:1.

21. The method of any one of claims 18-20, wherein the cap analog is a dinucleotide cap, a trinucleotide cap, or a tetranucleotide cap.

22. The method of any one of claims 18-21, wherein the cap analog is a trinucleotide cap analog comprising a GAG sequence.

23. The method of claim 22, wherein the GAG cap analog comprises a compound selected from:2020224103   26 Jun 2026(i);(ii); or(iii).

24. The method of any one of claims 18-23, wherein the cap analog is a tetranucleotide capanalog comprising a GGAG sequence.

25. The method of claim 24, wherein the tetranucleotide cap analog comprises a compoundselected from:2020224103   26 Jun 20260 OHHO' OH       NH2 (vi).

26. The method of any one of claims 17-25, wherein the polynucleotide template includes a 2‘-deoxythymidine residue or a 2‘-deoxycytidine residue at template position +1.2020224103   26 Jun 202627. A composition or kit comprising the RNA polymerase variant of any one of claims 1-16 and an IVT reaction component, optionally selected from the group consisting of a polynucleotide template, nucleoside triphosphates, and a cap analog.

28. A nucleic acid encoding the RNA polymerase variant of any one of claims 1-16.

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