19 results about "Site-specific recombination" patented technology

Among other things, provided herein are systems that replace the natural random integration activity of a retrovirus with site-specific integration machinery. This approach allows for a more precise targeting of a gene of interest into a human genome, e.g., for therapeutic purposes. The system may include integration-deficient retrovirus (e.g., lentivirus) (IDLV), in which the natural integration activity has been reduced (e.g., by mutation to the viral integrase polypeptide). Instead, the system may comprise a site-specific recombinase (e.g., a serine recombinase, e.g., a serine integrase) capable of directing insertion of a template DNA, or portion thereof, into a desired site in the human genome.

Disclosed herein are engineered LSR sequences, compositions, and uses including in genome-editing systems and therapeutic compositions. The LSRs can facilitate nucleic acid recombination at particular attachment sites, using suitable donor sequences. The disclosed LSRs may be used to site-specifically recombine or integrate nucleic acid sequences for a variety of purposes, including treatment of human diseases.

A homologous recombination method of excising a specific DNA sequence from a DNA molecule. The method includes providing the DNA molecule including a pair of target sequences that are a target of a site-specific recombination enzyme and a pair of homologous sequences that are DNA sequences sharing homology with each other. The pair of target sequences are oriented in different directions from each other and arranged on opposite sides of the specific DNA sequence. The pair of homologous sequences are arranged on opposite sides of the specific DNA sequence at positions further outside of the pair of target sequences. The method further includes inducing homologous recombination between the pair of homologous sequences by action of the site-specific recombination enzyme on the DNA molecule so that the specific DNA sequence and the pair of target sequences are excised from the DNA molecule.

Recombinant DNA molecules and constructs are provided that are useful for modulating gene expression in plants. One or more expression cassette(s) of a recombinant DNA molecule or construct may be excised from transgenic plants following transformation by the presence of flanking site-specific recombination sites in the recombinant DNA molecule or construct by expression of a recombinase enzyme encoded by the recombinant DNA molecule or construct. Such a recombinase system may be used to remove such expression cassette(s) from plants transformed with the recombinant DNA construct or vector. The recombinase transgene may be operably linked to a tissue-preferred or tissue-specific promoter for autoexcision in transformed plants without crossing to a different transgenic line expressing the recombinase. Methods for causing autoexcision of one or more expression cassette(s) in a transgenic plant, and plants and cells containing or transformed with a recombinant DNA molecule or construct of the present disclosure, are also provided.

Recombinant DNA molecules and constructs are provided that are useful for modulating gene expression in plants. One or more expression cassette(s) of a recombinant DNA molecule or construct may be excised from transgenic plants following transformation by the presence of flanking site-specific recombination sites in the recombinant DNA molecule or construct by expression of a recombinase enzyme encoded by the recombinant DNA molecule or construct. Such a recombinase system may be used to remove such expression cassette(s) from plants transformed with the recombinant DNA construct or vector. The recombinase transgene may be operably linked to a tissue-preferred or tissue-specific promoter for autoexcision in transformed plants without crossing to a different transgenic line expressing the recombinase. Methods for causing autoexcision of one or more expression cassette(s) in a transgenic plant, and plants and cells containing or transformed with a recombinant DNA molecule or construct of the present disclosure, are also provided.

The application discloses a corynebacterium striatum phage and application thereof. The corynebacterium striatum phage is a corynebacterium striatum phage CSP1, the preservation number of which is CGMCC NO: 45598, and the preservation time is July 4, 2023. The corynebacterium striatum phage has strong tolerance, biological safety and carries site-specific recombination functional elements (integrase and recombination sites). Meanwhile, the corynebacterium striatum phage can lyse 20 strains of multi-drug resistant corynebacterium striatum, and lays a foundation for subsequent medical researches using the corynebacterium striatum phage as a test and treatment carrier, a targeted pathogenic bacterium or symbiotic bacterium, and an immune regulator inducer.

The present disclosure relates to a novel screening method for screening a plurality of pGREs in parallel and nucleotide constructs for use in the method. The construction body comprises a nucleotide block, the sequence of the nucleotide block is PRIMREG1-pGREE-PRIMREG2-GENEE or GENE-PRIMREG1-pGREE-PRIMREG2, and the PRIMREG1 is a primer recognition sequence 1 or an FLEx box containing the primer recognition sequence 1. PGRE is a presumed gene regulatory element, PRIMREG2 is a primer recognition sequence 2 or a FLEx cassette comprising a primer recognition sequence 2, GENE comprises nucleotide blocks REPSEQ, IRES and SSR, where REPSEQ is a reporter gene and is present or absent, IRES is an internal ribosome entry site or a 2A self-cleaving peptide, and SSR is a site-specific recombinase gene. At least one of the PRIMREG1 and the PRIMREG2 is a FLEx cassette comprising a primer recognition sequence.

The invention belongs to the technical field of bioengineering, and particularly relates to a recombinant plasmid for promoting synthesis of tylosin, an engineering bacterium and a preparation method thereof, the genetically engineered bacterium (Streptomyces fradiae G3-F2) is preserved in China Center for Type Culture Collection on February 24, 2025, and the preservation number is CCTCC NO: M 2025278. According to the streptomyces fradiae G3-F2 disclosed by the invention, through site-specific recombination, a recombinant plasmid is constructed by utilizing an optimized ZouA gene DNA amplification system, so that multi-copy increase of a tylF gene is realized, and further, streptomyces fradiae G3-F2 is prepared; the enzymatic reaction rate of the methyltransferase is greatly improved; the efficient conversion of the component C is realized; and low-temperature culture fermentation is combined, so that the tylosin synthesis rate and efficiency are greatly improved. The titer of the strain in a 50L tank can reach 18500U / mL under the low-temperature culture condition of 28 DEG C, so that the production cost can be greatly reduced.

The application discloses a method for continuous editing of multi-site chromosomes in eukaryotic cells. The application provides a method for integrating the genome of eukaryotic cells, comprising: using a knock-in site-specific recombination site (such as noxM) in the genome of eukaryotic cells, realizing integration of a large fragment circular DNA molecule at a specific site of the genome under the action of a knock-in site-specific recombinase (such as Nigri), and simultaneously using an adjacent knock-out site-specific recombination site (such as loxP or a mutant thereof), rearranging the related sites under the action of a knock-out site-specific recombinase (such as Cre), so as to realize continuity of integration. The novel editing platform of high-efficiency site-specific recombination provided by the application can realize directional, continuous and multi-site integration of a large fragment DNA in eukaryotic cells, and the application has important application prospects in the field of biological technologies including plant breeding, animal cell line development, fungus engineering and the like.

This invention belongs to the field of bioengineering technology, specifically relating to a recombinant plasmid for tylosin synthesis, an engineered bacterial strain, and its preparation method. The genetically engineered bacterial strain (Streptomyces freundii G3-F2) was deposited at the China Center for Type Culture Collection (CCTCC) on February 24, 2025, with accession number CCTCC NO: M 2025278. This invention achieves site-specific recombination, utilizes an optimized ZouA gene DNA amplification system to construct the recombinant plasmid, and realizes… tulle Multiple copies of the F gene were increased, resulting in the preparation of *Streptomyces freundii* G3-F2. This significantly improved the rate of methyltransferase enzymatic reaction and achieved efficient conversion of component C. Combined with low-temperature fermentation, the rate and efficiency of tylosin synthesis were greatly enhanced. The strain achieved a titer of 18500 U / mL in a 50L tank under 28℃ low-temperature culture conditions, which can significantly reduce production costs.

The application provides a tumor cell dormancy and awakening marker tracing system (DormTracer), specifically, the system combines a gene switch and a site-specific recombination technology, expression of a reporter gene is driven by a recombination enzyme fused with a dormancy marker protein, the reporter gene is affected by a cell dormancy history, but does not affect the cycle of cell dormancy and proliferation, therefore, the tumor cell dormancy history can be traced, and the current instantaneous state of the cell is not limited to monitoring. The system can distinguish tumor cells in three states of proliferation, dormancy and dormancy awakening.

The invention relates to a method for tracing mononuclear macrophages. Comprising the following steps: placing a coding sequence of a fusion protein formed by connecting a site-specific recombinase and a ligand binding domain which can be combined with an exogenous ligand and regulate and control the activity of the recombinase after combination under the control of a regulation and control element of a C3aR1 gene, so that the expression of the fusion protein is limited in a cell with a C3aR1 expression history; setting an excidable blocking sequence corresponding to the recombinase recognition site in a genome of the recombinase recognition site, so that the blocking sequence inhibits the expression of a signal output molecule when the recombinase recognition site is not recombined; after the exogenous ligand is given, the recombinase is activated by regulating and controlling the conformational change of the ligand binding domain in the fusion protein, so that the recombinase is cut off the resectable blocking sequence, and the inhibition on the signal output molecule is relieved; and the signal output molecule for tracing is irreversibly expressed in the mononuclear macrophage with the C3aR1 expression history.

Compositions and methods are provided for the introduction and the regulated expression of genes in plants. Compositions include promoter constructs that provide a level of activity useful for the regulated expression of site-specific recombinases, while avoiding premature excision. Further provided are isolated polynucleotides encoding novel babyboom polypeptides, expression cassettes, and plants comprising the same. Methods for the introduction of genes into plants are provided, including methods for plastid transformation and methods for the transformation of tissues from mature seeds and leaves.

Disclosed herein are engineered LSR sequences, compositions, and uses including in genome-editing systems and therapeutic compositions. The LSRs can facilitate nucleic acid recombination at particular attachment sites, using suitable donor sequences. The disclosed LSRs may be used to site-specifically recombine or integrate nucleic acid sequences for a variety of purposes, including treatment of human diseases.

The present invention is related to a nucleic acid molecule, which is also referred to as third nucleic acid molecule, wherein the third nucleic acid molecule comprises(1) a nucleic acid molecule comprising the following elements:(a) optionally, a first part of a genome of a virus;(b) a nucleotide sequence, preferably a genomic nucleotide sequence, or a transcription unit;(c) a regulatory nucleic acid sequence which has a regulatory activity in a prokaryote;(d) exactly one site-specific recombination site;(e) a nucleotide sequence providing for a negative selection marker;(f) a bacterial nucleotide sequence unit comprising (i) bacterial nucleotide sequences for conditional replication and (ii) a nucleotide sequence providing for a positive selection marker;(g) optionally a first restriction site; or(2) a nucleic acid molecule comprising a nucleotide sequence according to SEQ ID NO: 6; or(3) a nucleic acid molecule identical or similar to the nucleic acid molecule contained in the organism deposited with the DSMZ under the Budapest treaty under accession number DSM 23754, wherein preferably the nucleic acid molecule contained in the organism is a heterologous nucleic acid molecule;wherein the third nucleic acid molecule is either a linear or a circular molecule.

The invention relates to methods and systems for gene editing combining endonuclease mediated homology directed repair using single stranded oligonucleotides templates with a site-specific recombinase to allow large cargos to be integrated at any location in the genome.

Provided herein are methods of generating a transgenic animal that include (a) generating an exogenous nucleic acid sequence, (b) inserting the exogenous nucleic acid sequence into a genome of an animal, wherein the exogenous nucleic acid sequence comprises a pair of site-specific recombinase recognition sequences, and wherein the exogenous nucleic acid sequence is introduced into the genome of the animal by using a gene-editing agent, thereby generating a transgenic animal, and optionally (c) delivering a transgene and a recombinase to the transgenic animal, wherein the transgene is integrated into the genome of the animal at a site of the site-specific recombinase recognition sequence, and wherein expression of the transgene is under control of an endogenous promoter of the gene locus, thereby altering somatic cells of the transgenic animal.

The present disclosure concerns evaluation as to whether or not a nucleic acid fragment having a target gene had been accurately integrated into the host genome. A group of nucleic acid fragments comprising a nucleic acid fragment having a target gene is introduced into host cells, and host cells in which the target gene had been cleaved from the genome DNA by the action of a site-specific recombinase are selected.

The present invention is in the field of recombinase and provides a method of producing site-specific DNA recombination comprising the steps of: a) contacting a nucleic acid comprising at least a first and a second recognition site, which are substantially identical or substantially reverse complementary to each other, with a protein having recombinase activity; and b) enabling the protein with recombinase activity to generate site-specific DNA recombination, wherein the recognition site comprises a first half site, a spacer region and a second half site, and wherein substantially identical or substantially reverse complementary to each other means that the nucleotide sequences of the first and second half-sites in the first recognition site may deviate from the nucleotide sequences of the first and second half-sites in the second recognition site by at most two nucleotides, wherein the protein having recombinase activity comprises an amino acid sequence having at least 80% identity to any one of SEQ ID NO: 1 to 9, and wherein the at least two recognition sites comprise: a nucleic acid sequence of any one of SEQ ID NO: 10 to 17 or a functional mutant thereof, or a nucleic acid sequence reverse complementary to any one of SEQ ID NO: 10 to 17 or a functional mutant thereof, wherein the functional mutant comprises a nucleic acid sequence having at least 60% sequence identity to SEQ ID NO: 10 to 17.