674 results about "Double strand" patented technology

The invention provides double-stranded ribonucleic acid for reducing blood coagulation factor XI expression and a modifier and application of the double-stranded ribonucleic acid. Cell experiment results show that the oligonucleotide duplex can significantly inhibit the expression of the FXI gene, and can be used for developing anticoagulant drugs.

The invention discloses light-driven toxin-enriched composite hydrogel as well as a preparation method and application thereof. The composite hydrogel comprises light-driven hydrogel and detection hydrogel, the light-driven hydrogel is agarose hydrogel doped with Au (at) Ag core-shell nano particles; the detection hydrogel is a double strand formed by an okadaic acid aptamer and a complementary sequence cDNA thereof, and a double strand formed by a domoic acid aptamer and a complementary sequence DNAzyme thereof, the hairpin H1 is used for modifying a quenching group BHQ2 at the 3'end, the hairpin H2 is used for modifying a fluorophore Cy3 at the neck part, the hairpin H3 is used for modifying a fluorophore FAM and a quenching group BHQ1 at the two ends respectively, and the metal ion doped agarose hydrogel is used for catalyzing DNAzyme cyclic shearing; and the photo-thermal driving unit is positioned on the detection function unit. According to the present invention, with the composite system of upper layer photo-thermal enrichment and lower layer dual-signal detection, the rapid and high-sensitivity simultaneous detection of the okadaic acid and the domoic acid is achieved through the combination of the photo-thermal transpiration effect and the HCR and DNAzyme cyclic shearing reaction;

The invention discloses a divalent nucleic acid aptamer fluorescence detection method based on an exonuclease I auxiliary target circulation strategy, and belongs to the field of analysis and detection.The divalent nucleic acid aptamer is a repetitive sequence composed of two monovalent nucleic acid aptamers and can form double-stranded DNA through base complementary pairing with complementary strand cDNA of the divalent nucleic acid aptamer, and the divalent nucleic acid aptamer can be used for fluorescence detection of the divalent nucleic acid aptamer. The method comprises the following steps: taking a bivalent nucleic acid aptamer as a template, forming a DNA silver nanocluster (DNA-AgNCs) under the action of silver nitrate and sodium borohydride, and when the target okadaic acid exists, combining the bivalent nucleic acid aptamer with the target, so that cDNA can be replaced from double-stranded DNA by the target. Exonuclease I is added to perform enzyme digestion on the cDNA and the divalent nucleic acid aptamer, so that the fluorescence intensity of the DNA-AgNCs can be rapidly reduced. The content of the okadaic acid can be judged by detecting the change of the fluorescence intensity. The invention provides a simple, convenient, rapid, high-sensitivity and high-specificity detection method for okadaic acid detection based on a divalent nucleic acid aptamer for the first time.

The disclosure provides, for example, a DNA molecule comprising a first strand of DNA, wherein the first strand is circular and single stranded over at least 90% of its length, and a second strand of DNA covalently linked to the first strand as described herein. The DNA molecule may comprise an effector sequence encoding a therapeutic effector. In some embodiments, the DNA molecule shows improved conversion to double-stranded DNA relative to a DNA molecule that lacks the second strand.

The invention relates to the field of veterinary drug residue detection, in particular to a fluorescence sensor based on DNA molecular machine mediated split Cas12a and application of the fluorescence sensor to ofloxacin detection, the fluorescence sensor comprises a system A, a system B and a system C. According to the final concentration of each system, the system A comprises an AP / CP double-stranded compound and a 20 mM Tris-HCl buffer solution 1, the system B comprises a double-stranded compound, an sRNA probe and a 10 mM Tris-HCl buffer solution 2, and the system C comprises a DNA molecular machine mediated split Cas12a. The system C comprises a Cas12a / hRNA compound, a pDNA / psG43 signal probe, ThT and a 20 mM Tris-HCl buffer solution; aP in the AP / CP double-chain compound is an aptamer of ofloxacin, and AP and CP in the AP / CP double-chain compound are paired and connected through complementary base pairing; the sequences of AP, CP, PS, SS, sRNA, hRNA, pDNA and psG43 are respectively as shown in SEQ ID NO.1-SEQ ID NO.8. The invention also discloses a kit for detecting the content of the protein. According to the application, the nucleic acid aptamer of ofloxacin is utilized, based on a DNA molecular machine and SCas12a as a signal amplification technology and sulfo-modified G43 as a fluorescent signal probe, even if the content of ofloxacin in a sample is extremely low, detection can be accurately realized.

Provided is a CFB-targeting double-stranded RNA molecule, specifically an siRNA. The provided siRNA can effectively inhibit the CFB expression, and can be used for preventing and treating diseases caused by up-regulated CFB expression or diseases associated with abnormal activation of an alternative complement pathway.

This disclosure relates to isolated oligonucleotides comprising duplex regions targeting human FXI mRNA, and delivery systems, kits and compositions comprising the same, and methods of using the same for inhibiting or downregulating FXI gene expression and treating or preventing a disease or disorder associated with aberrant or increased expression or activity of FXI or a disease or disorder where FXI plays a role.

Disclosed herein is a composition comprising a lipid nanoparticle and a double-stranded oligodeoxynucleotide (dsODN) encapsulated in the lipid nanoparticle. According to the embodiments of the present disclosure, the dsODN comprises two strands complementary to each other, in which the first strand comprises the nucleotide sequence of SEQ ID NO: 1. Also disclosed herein are methods of treating cancers by using the present composition.

Methods of processing pooled samples of single template molecules for sequencing are provided. Template nucleic acid segments are prepared and pooled. The prepared template nucleic acids include double stranded segments and a linking oligonucleotide with a unique, identifiable barcode sequence. The template nucleic acid segments are prepared by ligating a linking oligonucleotide segment to join the 3′ end of the first strand segment to the 5′ end of the second strand segment.

The present disclosure provides compositions comprising nucleic acid double-stranded splint adaptors, including kits, and methods that employ the double-stranded splint adaptors. The double-stranded splint adaptors (200) can be used in a one-pot, multi-enzyme reaction to introduce one or more new adaptor sequences into a library molecule. The double-stranded splint adaptor (200) comprises a first splint strand (long splint strand (300)) and a second splint strand (short splint strand (400)), where the first and second splint strands are hybridized together to form the double-stranded splint adaptor (200) having a double-stranded region and two flanking single-stranded regions. The second splint strand (400) carries the new adaptor sequence(s) to be introduced, such as for example a universal binding sequence, an index sequence and / or a random sequence.

Provided are a method for constructing a library based on an RNA sample and uses thereof. The method includes: step 1 of subjecting the RNA sample to a reverse transcription reaction to obtain DNA-RNA hybrid strands; step 2 of performing reaction of the DNA-RNA hybrid strands with an endoribonuclease, a first DNA polymerase, a second DNA polymerase, and dATPs to obtain a double-stranded DNA added with dA-tail, where the first DNA polymerase has a 5′-3′ exonuclease activity and a 3′-5′ exonuclease activity, and the second DNA polymerase has no 3′-5′ exonuclease activity; step 3 of ligating the double-stranded DNA added with dA-tail and a sequencing adaptor to obtain a ligated product; and step 4 of subjecting the ligated product to PCR amplification to obtain a sequencing library.

Double-stranded ribonucleic acid (dsRNAi) agents that target exon 1 of the huntingtin (HTT) gene are provided.SOLUTION: A double-stranded ribonucleic acid (dsRNA) agent for inhibiting the expression of huntingtin (HTT), the agent comprising a sense strand and an antisense strand forming a double-stranded region, wherein the sense strand comprises at least 15 contiguous nucleotides differing by no more than 3 nucleotides from a certain specific nucleotide sequence, and the antisense strand comprises at least 15 contiguous nucleotides differing by no more than 3 nucleotides from another certain specific nucleotide sequence, provided are dsRNA agents wherein one or more lipophilic moieties are conjugated to one or more internal positions on at least one of the sense or antisense strands.SELECTED DRAWING: None

The present disclosure relates to a nucleoside analogue and a use thereof. The nucleoside analogue is a compound shown in formula (Ia) or a prodrug thereof. The nucleoside analogue can enhance targeted delivery of oligonucleotide drugs to nervous system cells, thereby increasing the inhibition rate of the oligonucleotide drugs delivered in a targeted manner on expression of specific genes in the nervous system cells, or enabling the oligonucleotide drugs delivered in a targeted manner to achieve the purpose of preventing and / or treating pathological conditions or diseases caused by abnormal expression of the specific genes in the nervous system cells. The present disclosure also relates to a nucleotide analogue-containing double-stranded oligonucleotide and a use thereof. The double-stranded oligonucleotide comprises a sense strand and an antisense strand, each strand has 17-25 modified and / or unmodified nucleotides, and the antisense strand and the sense strand are complementary to form a duplex region; the sense strand and / or the antisense strand contains at least one nucleotide analogue represented by the structure of formula (100), or a tautomer, or stereoisomer, or pharmaceutically acceptable salt thereof; the double-stranded oligonucleotide can effectively treat and / or prevent pathological conditions or diseases caused by abnormal expression of specific genes in nervous system cells.

Embodiments of the invention include a method of purifying circular RNA (circRNA) from a solution. The method an include steps of (a) incubating the solution at about 55°C, (b) cellulose chromatography, (c) desalting and purifying RNA reactions with magnetic carboxylic acid beads, (d) ethanol precipitation to remove double stranded RNA byproducts and concentrated RNA, (e) poly-A polymerase treatment, (f) desalting and purifying RNA reactions with magnetic carboxylic acid beads to remove poly A reaction components, (g) RNase R treatment, and (h) desalting and purifying the solution to yield purified circRNA. In aspects, the method removes, among other contaminates, in vitro transcribed circular RNA from linear and doubled stranded RNA.

This invention provides a method and kit for enhancing the yield and quality of gene synthesis products, comprising the following steps: providing a total primer mixture, which includes multiple oligonucleotide single strands encoding a target gene sequence / encoding an operational sequence and sterile water; using the primer mixture as a template, performing the first... PCR The reaction yielded the primary spliced ​​product; a second reaction was then performed using start and end primers. PCR The reaction yielded the crude gene synthesis product; nested primers were then used for a third reaction. PCR The reaction yields a nested structure. PCR Products; nested PCR The product was subjected to agarose gel electrophoresis, and the target band was excised and recovered. This application improves upon traditional gene synthesis methods by adding operation sequences to both ends of the synthesized gene sequence and utilizing highly specific nested primers for nested gene synthesis. PCR It can synthesize more than 2000bp in one go. DNA Double-stranded sequences significantly improve the yield and quality of gene synthesis products.

The invention provides a novel base editor and application thereof. Specifically, the invention provides a novel double-stranded DNA deaminase, and a fusion protein (novel base editor), a base editing system, a base editing method and the like based on the novel double-stranded DNA deaminase, so as to improve the DNA editing efficiency of eukaryotic cell genes (especially mitochondrial genes), and especially improve the editing efficiency of non-TC DNA fragments such as' AC ',' GC 'and the like. According to the method, the types of the DNA fragments which can be effectively edited are expanded, and a wider prospect is provided for clinical application of DNA editing.

Disclosed is a method for editing mitochondrial DNA (mtDNA) within a cell, which include introducing into the cell (a) a DNA cleaving enzyme targeted to the mtDNA sequence to be deleted; (b) a first DNA binding component targeted to a sequence adjacent to the 5′ end of a mtDNA sequence to be deleted; and (c) a second DNA binding component targeted to a sequence adjacent to the 3′ end of the mtDNA sequence to be deleted, where the DNA cleaving enzyme generates a double stranded break (DSB) within the mtDNA sequence to be deleted or generates a single strand nick on the light strand of the mtDNA sequence to be deleted, and wherein the mtDNA sequence between the target sequence for the first DNA binding component and the target sequence for the second DNA binding component is deleted.

Provided are an siRNA targeting AZGP1 and the use thereof in the preparation of a drug for tumor treatment. An siRNA molecule for inhibiting the expression of an AZGP1 gene may be AZGP1-1, AZGP1-2, AZGP1-3, AZGP1-4, AZGP1-5, AZGP1-6 or AZGP1-7. The siRNA molecule comprises a sense strand and an antisense strand. The sense strand can be at least partially reverse complementary to the antisense strand to form a double-stranded region. The provided siRNA molecule targeting the AZGP1 gene can inhibit the invasion, proliferation and epithelial-mesenchymal transition of breast cancer cells, and is of great significance for treating cancer, especially breast cancer, by inhibiting the expression of the AZGP1 gene.

This invention belongs to the field of membrane separation and functional membrane materials technology, and discloses a chiral graphene oxide-based separation membrane, its preparation method, and its application. The membrane is composed of graphene oxide and / or reduced graphene oxide sheets and a single-stranded DNA-single-walled carbon nanotube complex. The single-stranded DNA helically winds around the outer surface of the single-walled carbon nanotubes to form a one-dimensional chiral nanochannel and intercalates between the sheets, forming a three-dimensional chiral channel network connected in the membrane thickness direction. The preparation method includes: heating and decohexing salmon sperm double-stranded DNA in a urea-containing buffer to obtain single-stranded DNA; dispersing single-walled carbon nanotubes and then complexing them with the single-stranded DNA; further mixing with a graphene oxide or reduced graphene oxide dispersion; and vacuum filtration to form the membrane. This membrane exhibits a high separation factor for chiral enantiomers such as L / D-phenylalanine, with an excess value of up to 99.95% for L-phenylalanine enantiomers after multi-stage separation, making it suitable for the efficient separation of chiral drugs and amino acids.

The application provides a double-stranded walking type DNA nanomachine and a preparation method and application thereof, and relates to the technical field of fluorescent analysis and detection.The double-stranded walking type DNA nanomachine for ctDNA fluorescent detection comprises a gold nanoparticle carrier, an anchor probe, a FAM fluorescent reporter probe, a double-stranded walking arm, a Cas12a protein and a crRNA to form a ribonucleoprotein complex.The walking arm of a conventional CRISPR / Cas12a nanomachine is a DNA single-stranded structure, which is easily cut in trans by activated Cas12a, thereby reducing the stability and sensitivity of the nanomachine.The application introduces a double-stranded DNA structure into the walking arm design to replace the conventional DNA single-stranded walking arm, constructs a double-stranded walking type three-dimensional DNA CRISPR / Cas12a nanomachine, effectively resists the reverse cutting of Cas12a on the walking arm, maintains the structural integrity and functional stability of the nanomachine, and greatly improves the detection sensitivity and specificity of lung cancer ctDNA, thereby having a good clinical application prospect.

The present disclosure provides compositions comprising nucleic acid double-stranded splint adaptors, including kits, and methods that employ the double-stranded splint adaptors. The double-stranded splint adaptors (200) can be used in a one-pot, multi-enzyme reaction to introduce one or more new adaptor sequences into a library molecule. The double-stranded splint adaptor (200) comprises a first splint strand (long splint strand (300)) and a second splint strand (short splint strand (400)), where the first and second splint strands are hybridized together to form the double-stranded splint adaptor (200) having a double-stranded region and two flanking single-stranded regions. The second splint strand (400) carries the new adaptor sequence(s) to be introduced, such as for example a universal binding sequence and / or an index sequence.

Provided herein are systems and methods for determining a level of disease, methylation, minimal residual diseases (MRDs) in an individual. Provided herein are systems and methods for retaining double-stranded context of a double-stranded nucleic acid molecule during sequencing.

The invention discloses a cholesterol modified double-stranded DNA membrane skeleton liposome delivery system and a preparation method and application thereof, and belongs to the technical field of drug delivery. The system is composed of cholesterol, distearoyl phosphatidylcholine, distearoyl phosphatidyl ethanolamine modified by methoxy polyethylene glycol and double-stranded DNA (chol-dsDNA) modified by 5 '-cholesterol, and the chol-dsDNA is anchored on the inner side and the outer side of a liposome membrane through a hydrophobic effect to form a bionic skeleton. The system is excellent in mechanical stability, low in drug leakage rate, high in tumor targeted enrichment capacity and good in biocompatibility, can efficiently entrap irinotecan hydrochloride and other hydrophilic drugs, is used for tumor treatment, and is simple and convenient to prepare and easy to scale.

siRNA, e.g., double stranded ribonucleic acid (dsRNA), is provided to interfere with target gene expression or inhibit its expression. A conjugate or a pharmaceutical composition contains the siRNA. And the use of the siRNA, the conjugate and the pharmaceutical composition thereof in preparing a drug used for treating and / or preventing the disease or disorder are also provided.

Provided are a prime editing system-based method for achieving inversion editing of a large genomic fragment and a composition used. By means of the efficient multi-gene prime editing protein construct ePPEplus in plants, the inversion of large fragments in plants is achieved by means of designing paired pegRNAs (pegL and pegR), and then by means of processes such as reverse transcription, DNA double-stranded annealing, DNA strand synthesis, and repair. The pegL comprises RTT-L, and the pegR comprises RTT-R. The nucleotide sequence of RTT-L is identical to that of strand A at the right terminus of a double-stranded DNA to be inverted. The nucleotide sequence of RTT-R is identical to that of strand B at the left terminus of said DNA. By means of testing in the monocotyledonous plant wheat and dicotyledonous plants Nicotiana benthamiana and tomato, it is indicated that the method is an effective method for mediating precise inversion of large-fragment DNA in plants.

The invention provides a method for producing a partially closed deoxyribonucleic acid (DNA) product, wherein the method comprises: (a) contacting a double-stranded DNA molecule with an endonuclease a

The invention discloses a cell membrane in-situ drug membrane protein target screening method based on variable configuration DNA, and belongs to the technical field of biological medicine. Two pairs of functionalized nucleic acid structures are constructed, the first pair is S1S2 semi-complementary DNA double strands, the second pair is S3S4 DNA-RNA hybrid double strands, and the S1S2 structure is covalently coupled to a non-natural amino acid site-directed modified membrane protein through a click chemical reaction in a living cell to realize tagging of the membrane protein; when the candidate drug coupled in S3 interacts with the membrane protein, triggering an allosteric response system to release the tagged chain in S1; the released DNA tag is subjected to PCR amplification and sequencing, and accurate identification and analysis of a membrane protein target are realized according to a tag sequence. The invention provides a high-specificity and non-in-vitro drug membrane protein target screening technology. According to the technology, active compound discovery or accurate screening of drug membrane protein targets in a living cell in-situ environment can be realized.

The invention discloses an activity detection method of formamide pyrimidine-DNA (deoxyribonucleic acid) glycosylase, which comprises the following steps: providing a double-chain probe which comprises two complementary single-chain probes containing 8-oxoG (8-oxoG) modification sites; uniformly mixing the Fpg enzyme, the double-stranded probe, a buffer solution and water to form a mixed system; carrying out PCR (Polymerase Chain Reaction) on the mixed system, and cutting the double-stranded probe containing the 8-oxoG modification site by using Fpg enzyme to obtain a longer and shorter fragment sample; performing electrophoresis on the fragment sample by using non-denaturing polyacrylamide gel; the non-denaturing polyacrylamide gel obtained after electrophoresis is completed is subjected to vibration dyeing, and a dyeing result is photographed so as to detect the activity of the Fpg enzyme. Compared with the prior art, the method is relatively simple and easy to operate, the reagent cost is relatively low, and the experimental result is sensitive and easy to observe; no radioactive and cancerogenic substance pollution exists, and the method is environment-friendly.

The application relates to the field of biological medicine, and particularly relates to application of a TMEM119 gene or protein in development of an anti-gastric cancer drug, and particularly to application of a TMEM119 inhibitor in preparation of an anti-gastric cancer drug, wherein the inhibitor can be a small-molecule nucleotide for targeted knockdown of the TMEM119 gene or protein, the small-molecule nucleotide is shRNA or siRNA, the shRNA is a double-stranded oligonucleotide composed of complementary base sequences shown in SEQ ID NO. 1-2 or SEQ ID NO. 3-4; and the siRNA has a guide strand with a base sequence shown in SEQ ID NO. 7 or SEQ ID NO. 8. Experiments prove that when the expression of the TMEM119 gene of human gastric cancer cells is knocked down, the viability and the colony formation ability of the human gastric cancer cells are significantly reduced, thereby inhibiting the proliferation and survival of the gastric cancer cells, and further achieving the effect of restraining the occurrence, development, recurrence or metastasis of the gastric cancer.

The invention relates to a method for evaluating and positioning nucleic acid pollution of a nucleic acid extraction kit, which comprises the following steps: 1) taking nucleic acid-free water as a negative sample, and performing nucleic acid extraction on the nucleic acid-free water by using the nucleic acid extraction kit according to nucleic acid extraction steps in the kit, the obtained nucleic acid is presumed as the polluted nucleic acid in the nucleic acid extraction kit; 2) amplifying polluted nucleic acid, purifying a PCR product, enriching double-chain cDNA, and determining the concentration of the double-chain cDNA so as to perform quantification, sample mixing and quality control treatment before library construction; (3) carrying out high-throughput deep sequencing by adopting a platform of the Illumina company, and then carrying out bioinformatics analysis to obtain classification information and gene sequences of polluted nucleic acid; and 4) designing a specific primer based on the gene sequence of the polluted nucleic acid, and carrying out pollution evaluation and positioning verification on each component of the nucleic acid extraction kit through qPCR (Quantitative Polymerase Chain Reaction).