WO2017215619A1 - Protéine de fusion produisant une mutation ponctuelle dans une cellule, sa préparation et son utilisation - Google Patents

Protéine de fusion produisant une mutation ponctuelle dans une cellule, sa préparation et son utilisation Download PDF

Info

Publication number
WO2017215619A1
WO2017215619A1 PCT/CN2017/088369 CN2017088369W WO2017215619A1 WO 2017215619 A1 WO2017215619 A1 WO 2017215619A1 CN 2017088369 W CN2017088369 W CN 2017088369W WO 2017215619 A1 WO2017215619 A1 WO 2017215619A1
Authority
WO
WIPO (PCT)
Prior art keywords
amino acid
seq
fusion protein
sequence
protein
Prior art date
Application number
PCT/CN2017/088369
Other languages
English (en)
Chinese (zh)
Inventor
常兴
Original Assignee
中国科学院上海生命科学研究院
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 中国科学院上海生命科学研究院 filed Critical 中国科学院上海生命科学研究院
Publication of WO2017215619A1 publication Critical patent/WO2017215619A1/fr

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K19/00Hybrid peptides, i.e. peptides covalently bound to nucleic acids, or non-covalently bound protein-protein complexes
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N9/00Enzymes; Proenzymes; Compositions thereof; Processes for preparing, activating, inhibiting, separating or purifying enzymes
    • C12N9/14Hydrolases (3)
    • C12N9/16Hydrolases (3) acting on ester bonds (3.1)
    • C12N9/22Ribonucleases RNAses, DNAses
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N15/00Mutation or genetic engineering; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification; Use of hosts therefor
    • C12N15/09Recombinant DNA-technology
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N15/00Mutation or genetic engineering; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification; Use of hosts therefor
    • C12N15/09Recombinant DNA-technology
    • C12N15/63Introduction of foreign genetic material using vectors; Vectors; Use of hosts therefor; Regulation of expression
    • C12N15/79Vectors or expression systems specially adapted for eukaryotic hosts
    • C12N15/85Vectors or expression systems specially adapted for eukaryotic hosts for animal cells
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N9/00Enzymes; Proenzymes; Compositions thereof; Processes for preparing, activating, inhibiting, separating or purifying enzymes
    • C12N9/14Hydrolases (3)
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N9/00Enzymes; Proenzymes; Compositions thereof; Processes for preparing, activating, inhibiting, separating or purifying enzymes
    • C12N9/14Hydrolases (3)
    • C12N9/78Hydrolases (3) acting on carbon to nitrogen bonds other than peptide bonds (3.5)
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12YENZYMES
    • C12Y305/00Hydrolases acting on carbon-nitrogen bonds, other than peptide bonds (3.5)
    • C12Y305/04Hydrolases acting on carbon-nitrogen bonds, other than peptide bonds (3.5) in cyclic amidines (3.5.4)
    • C12Y305/04001Cytosine deaminase (3.5.4.1)
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12YENZYMES
    • C12Y306/00Hydrolases acting on acid anhydrides (3.6)
    • C12Y306/04Hydrolases acting on acid anhydrides (3.6) acting on acid anhydrides; involved in cellular and subcellular movement (3.6.4)
    • C12Y306/04012DNA helicase (3.6.4.12)
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2319/00Fusion polypeptide
    • C07K2319/01Fusion polypeptide containing a localisation/targetting motif
    • C07K2319/02Fusion polypeptide containing a localisation/targetting motif containing a signal sequence
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2319/00Fusion polypeptide
    • C07K2319/01Fusion polypeptide containing a localisation/targetting motif
    • C07K2319/09Fusion polypeptide containing a localisation/targetting motif containing a nuclear localisation signal
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2319/00Fusion polypeptide
    • C07K2319/20Fusion polypeptide containing a tag with affinity for a non-protein ligand
    • C07K2319/21Fusion polypeptide containing a tag with affinity for a non-protein ligand containing a His-tag
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2319/00Fusion polypeptide
    • C07K2319/20Fusion polypeptide containing a tag with affinity for a non-protein ligand
    • C07K2319/22Fusion polypeptide containing a tag with affinity for a non-protein ligand containing a Strep-tag
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2319/00Fusion polypeptide
    • C07K2319/40Fusion polypeptide containing a tag for immunodetection, or an epitope for immunisation
    • C07K2319/41Fusion polypeptide containing a tag for immunodetection, or an epitope for immunisation containing a Myc-tag
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2319/00Fusion polypeptide
    • C07K2319/40Fusion polypeptide containing a tag for immunodetection, or an epitope for immunisation
    • C07K2319/42Fusion polypeptide containing a tag for immunodetection, or an epitope for immunisation containing a HA(hemagglutinin)-tag
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2319/00Fusion polypeptide
    • C07K2319/40Fusion polypeptide containing a tag for immunodetection, or an epitope for immunisation
    • C07K2319/43Fusion polypeptide containing a tag for immunodetection, or an epitope for immunisation containing a FLAG-tag
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2800/00Nucleic acids vectors
    • C12N2800/10Plasmid DNA
    • C12N2800/106Plasmid DNA for vertebrates
    • C12N2800/107Plasmid DNA for vertebrates for mammalian

Definitions

  • the present invention relates to fusion proteins which produce point mutations in cells, their preparation and use.
  • genotype There is a close relationship between genotype and phenotype.
  • spontaneous mutations cause genotypic changes that produce multiple phenotypes.
  • mutations are still made to diversify genes, produce a variety of phenotypes, and thus screen out functional mutants, study the relationship between genes and functions, and obtain more functional proteins.
  • the frequency of spontaneous mutations is extremely low.
  • the spontaneous mutation rate of human genome is 5.0 ⁇ 10 -10
  • the spontaneous mutation rate of mouse genome is 1.8 ⁇ 10 -10
  • the spontaneous mutation rate of E. coli genome is 5.4 ⁇ 10 -10
  • the spontaneous mutation rate of HIV is 3 ⁇ 10 -5
  • the spontaneous mutation frequency of the organism increases with the decrease of the biological genome [Holmes E C.
  • In vivo point mutation method 1. Physical method: ultraviolet radiation, mutation frequency is 1 ⁇ 10 -10 [Packer M S, Liu D R. Methods for the directed evolution of proteins [J]. Nature Reviews Genetics, 2015]. 2. Chemical method: ENU is an alkylating agent that transfers ethyl groups to the oxygen and nitrogen atoms of DNA, causing mismatches, base substitutions or deletions, with a mutation frequency of 1-1.5 ⁇ 10 -5 [FILBY.ZEBRAFISH :METHODS AND PROTOCOLS.METHODS IN MOLECULAR BIOLOGY ⁇ By GJLieschke, AC Oates and K.
  • B cells in the germinal center can produce multi-component antibodies by high-frequency mutation of somatic cells to resist the invasion of pathogens [Odegard VH, Schatz D G. Targeting of somatic hypermutation. [J]. Nature Reviews Immunology, 2006, 6(8): 573-583].
  • High-frequency mutations in somatic cells refer to non-template point mutations in the immunoglobulin heavy light chain variable region, which are associated with B cell affinity maturation [Odegard V H et al., supra].
  • the enzyme that mediates this process is activation-induced cytosine deaminase (AID).
  • AID is a cytosine deaminase belonging to the APOBEC family, an RNA editing enzyme family: N-terminal nuclear localization signal, C-terminal nuclear export signal, and its catalytic domain is shared by APOBEC family [Zhenming X, Hong Z , Pone EJ, et al. Immunoglobulin class-switch DNA recombination: induction, targeting and beyond. [J]. Nature Reviews Immunology, 2012, 12(7): 517-31]. It is generally believed that the N-terminal structure is necessary for SHM. The expression of AID is restricted to the B cells of the germinal center, and its function of point mutation is conditional. It must act on single-stranded DNA and has sequence preference.
  • the hotspot domain is RGYW [Kiyotsugu Y, Il-Mi O, Tomonori E, et al. AID Enzyme-Induced Hypermutation in an Actively Transcribed Gene in Fibroblasts [J]. Science, 2002, 296 (5575): 2033-2036].
  • R stands for A/G
  • Y stands for C/T
  • W stands for A/T. It can be seen that the function of AID is related to the primary structure of DNA. First, the deamination of cytosine on single-stranded DNA is changed to U to form a UG mismatch. If UG is not repaired, a CT GA conversion mutation will be formed during DNA replication.
  • U can be excised by UNG (uracil DNA glycosidase) to form a pyrimidine-free site, and four bases are randomly incorporated [Odegard V H et al., supra].
  • UNG uracil DNA glycosidase
  • the point mutations produced by the above process are significant for somatic high frequency mutations and can produce diverse antibodies.
  • the frequency of point mutations caused in vivo is 1 ⁇ 10 -4 -1 ⁇ 10 -3 , and the sites are random [Masatoshi A, Nesreen H, Andre S, et al.Accumulation of the FACT complex, as well as Histone H3.3, serves as a target marker for somatic hypermutation. [J]. Proceedings of the National Academy of Sciences of the United States of America, 2013, 110 (19): 7784-7789], still unable to meet the experimental screening mutation Required for the body.
  • the first aspect herein provides a fusion protein comprising a Cas enzyme having a cytosine deaminase and a nuclease activity loss, retaining an understanding of the chymase activity.
  • the fusion protein is formed by a Casase that lacks cytosine deaminase and nuclease activity, retains knowledge of the chymase activity.
  • the Cas enzyme is selected from the group consisting of: Cas1, Cas1B, Cas2, Cas3, Cas4, Cas5, Cas6, Cas7, Cas8, Cas9 (also known as Csn1 and Csx12), Cas10, Csy1, Csy2, Csy3, Cse1, Cse2, Csc1, Csc2, Csa5, Csn2, Csm2, Csm3, Csm4, Csm5, Csm6, Cmr1, Cmr3, Cmr4, Cmr5, Cmr6, Csb1, Csb2, Csb3, Csx17, Csx14, Csx10, Csx16, CsaX, Csx3, Csx1, Csx15, Csf1, Csf2, Csf3, Csf4, homologs thereof or modified forms thereof.
  • the nuclease activity of the Cas enzyme is partially deleted such that the Cas enzyme only causes DNA single strand breaks; or the nuclease activity of the Cas enzyme is all deleted, causing DNA double stranding fracture.
  • the Cas enzyme is a Cas9 enzyme selected from the group consisting of: Cas9 (SpCas9) from S. pyogenes, Cas9 (SaCas9) from S. aureus, and Cas9 from S. thermophilus ( St1Cas9).
  • the Cas enzyme is a Cas9 enzyme
  • the two endonuclease catalytic domains of the enzyme are mutated in RuvC1 and/or HNH, resulting in loss of nuclease activity of the enzyme .
  • both the RuvC1 and HNH of the Cas9 enzyme are mutated, resulting in a loss of the nuclease activity of the enzyme, retaining an understanding of the chymase activity.
  • the 10th amino acid asparagine of the Cas9 enzyme is mutated to alanine or other amino acid
  • the amino acid histidine at position 841 is mutated to alanine or other amino acid.
  • the amino acid sequence of the Cas9 enzyme is set forth in SEQ ID NO: 2, pp. 42-1452, or as shown in SEQ ID NO: 72, amino acid residues 42-1419.
  • the cytosine deaminase is a full length cytosine deaminase or a fragment thereof, wherein the fragment comprises at least an NLS domain, a catalytic domain, and an APOBEC-like cytosine deaminase Domain.
  • the cytosine deaminase undergoes a substitution mutation at amino acid residues 10, 82, and 156.
  • the substitution mutations are K10E, T82I, and E156G.
  • the fragment comprises at least amino acid residues 9-182 of the AID, eg, at least amino acid residues 1-182 of the AID.
  • the amino acid sequence of the cytosine deaminase is as shown in amino acids 1457-1654 of SEQ ID NO: 2, or as amino acid residues 1447-1629 of SEQ ID NO: 68 Show.
  • the fragment comprises at least amino acid residues 1465-1638 of SEQ ID NO: 2, eg, at least amino acid residues 1457-1638 of SEQ ID NO: 2.
  • the fragment consists of amino acid residues 1-182, consists of amino acid residues 1-164, or consists of amino acid residues 1-109.
  • the fusion protein further comprises one or more of the following sequences: A head, a nuclear localization sequence, and an amino acid residue or amino acid sequence introduced for the purpose of constructing a fusion protein, promoting expression of a recombinant protein, obtaining a recombinant protein that is automatically secreted outside the host cell, or facilitating purification of the recombinant protein.
  • the amino acid sequence of the fusion protein is set forth in SEQ ID NO: 2, 4, 66, 68, 70 or 72, or as shown in amino acids 26-1654 of SEQ ID NO: 2. Or as shown in SEQ ID NO: 4, positions 26-1638, or as shown in SEQ ID NO: 68, amino acids 26-1629, or as SEQ ID NO: 70, amino acids 26-1629, or as SEQ ID NO: 72 is shown in amino acids 26-1638.
  • a second aspect of the invention provides a polynucleotide sequence selected from the group consisting of:
  • a third aspect of the invention provides a nucleic acid construct comprising the polynucleotide sequence of the second aspect herein.
  • the nucleic acid construct is an expression vector for expression of a fusion protein described herein in a host cell.
  • a fourth aspect of the invention provides a host cell comprising a fusion protein, a coding sequence thereof or a nucleic acid construct as described herein.
  • a fifth aspect herein provides a method of producing a point mutation in a cell, the method comprising the step of expressing a fusion protein and sgRNA described herein in said cell.
  • the methods comprise the step of transferring a fusion protein described herein, or an expression vector thereof, and sgRNA or an expression vector thereof into the cell, followed by screening to obtain the desired mutated nucleic acid sequence.
  • the sgRNA comprises a target binding region and a Cas protein recognition region, the target binding region being capable of specifically binding to a nucleic acid sequence to be mutated, the Cas protein recognition region being capable of being The Cas enzyme recognizes and binds.
  • the target binding region of the sgRNA specifically binds to a template strand of a nucleic acid sequence to be mutated, and the contralateral region of the sgRNA binding region on the template strand is immediately adjacent to the anterior region sequence recognized by the Cas protein Adjacent motifs, or bases separated by 10 or less.
  • the gene to be mutated encodes a functional protein.
  • the functional protein includes proteins involved in the development, progression, and metastasis of diseases, proteins involved in cell differentiation, proliferation, and apoptosis, proteins involved in metabolism, development-related proteins, and Drug targets and so on.
  • the functional protein is selected from the group consisting of antibodies, enzymes, lipoproteins, hormone proteins, transport and storage proteins, motor proteins, receptor proteins, and membrane proteins.
  • a sixth aspect of the invention provides a kit comprising a fusion protein, polynucleotide sequence or nucleic acid construct as described herein.
  • a seventh aspect of the invention provides the use of a fusion protein, polynucleotide sequence or nucleic acid construct as described herein for producing a point mutation in a cell, or in the preparation of a composition or kit for producing a point mutation in a cell Applications.
  • Figure 1 A and C are PCR-amplified AID (lane 1) and AIDX fragment (lane 1); B is pEntr11-dCas9-AID plasmid agarose gel, in which one lane is pEntr11 empty plasmid, 2 The plasmid is pEntr11-dCas9 plasmid, the 3-7 lanes are pEntr11-dCas9-AID plasmid; D is the PCR result of pEntr11-dCas9-AIDX plasmid bacterial solution, and the amplified fragment is AIDX. Lanes 1-5 in D represent 5 different positive clones, respectively, and No. 6 is an empty plasmid as a negative control.
  • Figure 2 A, 1 and 2 lanes are respectively PCR-amplified dCas9-AID and dCas9-AIDX fragments; B, enzymatically cleavage of MO91 empty-loaded plasmid, one of which is BglII single-cut, and the other is MO91 empty Plasmid, 3 lanes are BglII and XhoI double digestion; C, MO91-dCas9-AIDX plasmid bacterial solution PCR results, the amplified fragment is AIDX; D, MO91-dCas9-AID plasmid bacterial solution PCR results, amplified The fragment is an AID.
  • Figure 3 A, 1 is the 3*flag+NLS fragment amplified by PCR, and 2 and 3 lanes are BglII single-cutting MO91-dCas9-AID plasmid and MO91-dCas9-AIDX plasmid, respectively, and 4 lanes are MO91- dCas9-AID plasmid control; B, 1-4 lanes are MO91-dCas9 (3*flag, NLS)-AID plasmid, lane 5 is MO91-dCas9-AID plasmid, and lane 6-9 is MO91-dCas9 (3*flag, NLS)-AIDX plasmid.
  • Figure 4 Sequence of the EGFP reporter, the stop codon is shown in bold. The designed sgRNA is indicated by an arrow.
  • Figure 5 Schematic representation of the pattern of the reporter plasmid.
  • Figure 6 Flow cytometry reporting cell line. The three curves from left to right indicate Thy1.1 expression levels of unstained controls, reporter negative cells, and reporter positive cells, respectively.
  • Figure 7 Comparison of dCas9-AID, dCas9-AIDX, AID and AIDX point mutation efficiencies in reporter cells.
  • Figure 8 Optimization of dCas9-AID point mutation efficiency in reporter cells.
  • A dCas9-AID induces GFP expression;
  • B a schematic of different AID variants and the efficiency of their induction of point mutations;
  • C dCas9-AIDX induces point mutations requiring cytosine deaminase activity of AID.
  • Figure 9 Point mutation frequency distribution of dCas9-AIDX and AID on EGFP and cMyc genes.
  • Figure 10 dCas9-AIDX randomly mutates C and G bases to three other bases.
  • A statistics of base mutation types;
  • B dCas9-AIDX induces point mutation mechanism.
  • Figure 12 dCas9-AIDX not only acts on exogenous genes, but also on endogenous genes.
  • Figure 13 Structural functional domain of the AID.
  • Figure 14 Experimental procedure (a) and results (b-d) of the application of dCas9-AIDX to the Gleevec resistance screening of the K562BCR-ABL gene.
  • FIG. 15 TAM (targeting cytosine deaminase AID-mediated gene mutation technique) mutating amino acids of the anti-HEL-IgG1 variable region.
  • TAM induces base mutations in the anti-HEL-IgG1 variable region (top panel) and can repeatedly induce base mutations in the IgGl CDRs (bottom panel).
  • Figure 17 The affinity of the mutated antibody for HEL is increased by more than 10 fold.
  • Figure 18 Results of expression of nCas9-AIDX in bacteria.
  • the boxed box is a band of nCas9-AIDX fusion protein.
  • Figure 19 Functional test results for different fusion proteins.
  • the three pillars from left to right represent the results of MO91-AIDX-XTEN-dCas9, MO91-dCas9-XTEN-AIDX, and MO91-dCas9-AIDX.
  • Figure 20 Functional test results for different fusion proteins.
  • the three pillars from left to right represent the results of MO91-dCas9-AIDX, MO91-dCas9-XTEN-AIDX (K10E T82I E156G) and MO91-dCas9-XTEN-AIDX.
  • Figure 21 Functional verification results of the nCas9-AIDX fusion protein.
  • This document relates to a fusion protein of Cas protein with nuclease activity and cytosine deaminase AID or a mutant thereof.
  • the fusion protein Under the guidance of sgRNA, the fusion protein is recruited to a specific DNA sequence, and AID or its mutant deamination of cytosine to produce uracil, which is then randomly mutated into other bases during DNA repair. High mutation efficiency is obtained while achieving site-directed mutagenesis.
  • CRISPR Clustered Regularly Interspaced Short Palindromic Repeats
  • a complex of a Cas protein with endonuclease activity and its specifically recognized sgRNA is complementary paired with a template strand in the target DNA by a pairing region of the sgRNA, and the double stranded DNA is cleaved by Cas at a specific position.
  • Cas protein and “Cas enzyme” are used interchangeably herein.
  • Cas/sgRNA The above-described property of Cas/sgRNA is utilized herein to utilize sgRNA specific binding to a target to position Cas to a desired position at which the cytosine is deaminated by AID or a mutant thereof in the fusion protein.
  • Partial or complete deletions of nuclease activity suitable for use in the present invention, particularly partial or complete deletion of endonuclease activity, but retaining knowledge of the chymase activity may be derived from various Cas proteins and variants thereof well known in the art.
  • a Cas9 enzyme lacking nuclease activity and a single-stranded sgRNA specifically recognized by the same are used.
  • the Cas9 enzyme may be a Cas9 enzyme from a different species including, but not limited to, Cas9 (SpCas9) from S. pyogenes, Cas9 (SaCas9) from S. aureus, and Cas9 (St1 Cas9) from Streptococcus thermophilus, and the like.
  • Various variants of the Cas9 enzyme can be used as long as the Cas9 enzyme specifically recognizes its sgRNA and lacks nuclease activity.
  • the Cas protein with nuclease activity deletion can be prepared by methods well known in the art, including but not limited to deletion of the entire catalytic domain of the endonuclease in the Cas protein or mutation of one or several amino acids in the domain. Thereby producing a Cas protein lacking in nuclease activity.
  • the mutation may be one or several (for example, two or more, three or more, four or more, five or more, more than ten, to the entire catalytic domain) deletion or substitution of amino acid residues, or one or several new amino acids. Insertion of residues (for example, one or more, two or more, three or more, four or more, five or more, ten or more, or 1 to 10, and 1 to 15).
  • Deletion of the above domains or mutation of amino acid residues can be carried out by methods conventional in the art, and whether the Cas protein after the mutation also has nuclease activity.
  • Cas9 its two endonuclease catalytic domains, RuvC1 and HNH, can be mutated, for example, the 10th amino acid of the enzyme (in the RuvC1 domain) is mutated to alanine or other An amino acid that mutates the histidine of amino acid 841 (located in the HNH domain) to alanine or other amino acids.
  • the Cas enzyme is completely nuclease free.
  • the amino acid sequence of the nuclease-free Cas9 enzyme used herein is set forth in SEQ ID NO: 2, pp. 42-1452.
  • the Cas enzyme portion used herein lacks nuclease activity, ie, the Cas enzyme can cause DNA single strand breaks.
  • a representative example of such a Cas enzyme can be shown as amino acid residues 42-14-19 of SEQ ID NO:72.
  • the function of the Cas/sgRNA complex requires a protospacer adjacent motif (PAM) in the non-template strand (3' to 5') of the DNA.
  • PAM protospacer adjacent motif
  • Different Cas enzymes their corresponding PAMs are not identical.
  • the PAM for SpCas9 is typically NGG
  • the PAM for the SaCas9 enzyme is typically NNGRR
  • the PAM for the St1Cas9 enzyme is typically NNAGAA; wherein N is A, C, T or G and R is G or A.
  • the PAM for the SaCas9 enzyme is NNGRRT. In certain preferred embodiments, the PAM for SpCas9 is TGG.
  • sgRNA usually consists of two parts: a target binding region and a Cas protein recognition region.
  • the target binding region and the Cas protein recognition region are usually joined in the 5' to 3' direction.
  • the target binding region is typically 15 to 25 bases in length, more typically 18 to 22 bases, such as 20 bases.
  • the target binding region specifically binds to the template strand of DNA, thereby recruiting the fusion protein to a predetermined site.
  • the contralateral region of the sgRNA binding region on the DNA template strand is in close proximity to the PAM, or is separated by a few bases (eg, within 10, or within 8 or within 5). Therefore, when designing sgRNA, the PAM of the enzyme is usually determined according to the Cas enzyme used, and then a site which can be used as a PAM is found on the non-template strand of DNA, and then the non-template strand (3' to 5') PAM is used. Fragments 15 to 25 bases long, more usually 18 to 22 bases long downstream of the PAM site or within 10 (eg, within 8 or less, etc.) of the PAM site A sequence that is the target binding region of sgRNA.
  • the Cas protein recognition region of sgRNA is determined based on the Cas protein used, which is well known to those skilled in the art.
  • the sequence of the target binding region of the sgRNA herein is that the DNA strand containing the PAM site recognized by the selected Cas enzyme is immediately downstream of the PAM site or within 10 of the PAM site (for example, 8 or less, 5 Fragments of 15 to 25 bases in length, usually 18 to 22 bases in length; the Cas protein recognition region is specifically recognized by the selected Cas enzyme.
  • the sgRNA can be prepared by methods conventional in the art, for example, by conventional chemical synthesis methods.
  • the sgRNA can also be transformed into cells via an expression vector to express the sgRNA in the cell.
  • Expression vectors for sgRNA can be constructed using methods well known in the art.
  • AID is a cytosine deaminase belonging to the APOBEC family, an RNA editing enzyme family: a nuclear localization signal at the N-terminus and a nuclear export signal at the C-terminus.
  • the catalytic domain is shared by the APOBEC family. It is generally believed that the N-terminal structure is required for somatic hypermutation (SHM).
  • SHM somatic hypermutation
  • AID function is deamination of cytosine, cytosine The pyridine becomes uracil, and subsequent DNA repair can turn uracil into other bases. It will be appreciated that cytosine deaminase, or fragments or mutants thereof that retain the biological activity of cytosine deamination, cytosine to uracil, are well known in the art.
  • amino acids 9-26 are nuclear localization (NLS) domains, especially amino acids 13-26 are involved in DNA binding, amino acids 56-94 are catalytic domains, amino acids 109-182 are APOBEC-like domains, and amino acids 193-198 are The nuclear export (NES) domain, amino acids 39-42 interact with catenin-like protein 1 (CTNNBL1), and amino acids 113-123 are hotspot recognition loops.
  • NLS nuclear localization
  • amino acids 39-42 interact with catenin-like protein 1 (CTNNBL1)
  • amino acids 113-123 are hotspot recognition loops.
  • a full length sequence of AID (as indicated by amino acids 1457-1654 of SEQ ID NO: 2) can also be used herein, and fragments of AID can also be used.
  • the fragment comprises at least an NLS domain, a catalytic domain and an APOBEC-like domain.
  • the fragment comprises at least amino acid residues 9-182 of the AID (ie, amino acid residues 1465-1638 of SEQ ID NO: 2).
  • the fragment comprises at least amino acid residues 1-182 of the AID (ie, amino acid residues 1457-1638 of SEQ ID NO: 2).
  • an AID fragment as used herein consists of amino acid residues 1-182, consists of amino acid residues 1-164, or consists of amino acid residues 1-190.
  • the AID fragment used herein consists of amino acid residues 1457-1638 of SEQ ID NO: 2, amino acid residues 1457-1642 of SEQ ID NO: 2, or SEQ ID NO: 2 Amino acid residue composition of 1457-1646.
  • variants of AID that retain their cytosine deaminase activity can also be used herein.
  • such variants may correspond to a wild-type sequence of AIDs having from 1 to 10, such as 1-8, 1-5 or 1-3 amino acid variations, including deletions, substitutions and mutations of amino acids.
  • these amino acid variations do not occur within the above-described NLS domain, catalytic domain and APOBEC-like domain, or even within these domains do not affect the original biological function of these domains.
  • it is preferred that these variations do not occur at positions 24, 27, 38, 56, 58, 87, 90, 112, 140, etc. of the AID amino acid sequence.
  • these variations also do not occur within amino acids 39-42, amino acids 113-123.
  • variation can occur among amino acids 1-8, amino acids 28-37, amino acids 43-55, and/or amino acids 183-198.
  • the variation occurs at positions 10, 82, and 156.
  • substitution mutations occur at positions 10, 82, and 156, and such substitution mutations can be K10E, T82I, and E156G.
  • the amino acid sequence of an exemplary AID mutant comprises the amino acid sequence set forth at positions 1447-1629 of SEQ ID NO: 68, or the amino acid set forth at positions 1447-1629 of SEQ ID NO:68. Residue composition.
  • fusion proteins comprising Cas enzyme and AID.
  • the Cas enzyme is usually at the N-terminus of the amino acid sequence of the fusion protein, and the AID is at the C-terminus.
  • fusion proteins formed primarily of Cas enzyme and AID are provided herein.
  • a fusion protein or similar expression "formed primarily by" herein does not mean that the fusion protein includes only Cas enzyme and AID, and the definition is understood to mean that the fusion protein may include only Cas enzyme and AID, or It may also contain other components that do not affect the targeting of the Cas enzyme in the fusion protein and the function of the AID mutant target sequence, including but not limited to various linker sequences, nuclear localization sequences, and gene cloning operations, as described below, And/or an amino acid sequence introduced in the fusion protein for the purpose of constructing a fusion protein, promoting expression of a recombinant protein, obtaining a recombinant protein that is automatically secreted outside the host cell, or facilitating detection and/or purification of the recombinant protein.
  • the Cas enzyme can be fused to the AID via a linker.
  • the linker may be a peptide of 3 to 25 residues, for example, a peptide of 3 to 15, 5 to 15, 10 to 20 residues. Suitable examples of peptide linkers are well known in the art.
  • the linker contains one or more motifs that are repeated before and after, and the motif typically contains Gly and/or Ser.
  • the motif can be SGGS, GSSGS, GGGS, GGGGS, SSSSG, GSGSA, and GGSGG.
  • the motif is contiguous in the linker sequence with no amino acid residues inserted between the repeats.
  • the linker sequence may comprise 1, 2, 3, 4 or 5 repeat motifs.
  • the linker sequence is a polyglycine linker sequence.
  • the amount of glycine in the linker sequence is not particularly limited, but is usually 2 to 20, for example, 2 to 15, 2 to 10, and 2 to 8.
  • the linker may also contain other known amino acid residues such as alanine (A), leucine (L), threonine (T), glutamic acid (E), styrene Amino acid (F), arginine (R), glutamine (Q), and the like.
  • the linker sequence is XTEN, the amino acid sequence of which is set forth in amino acid residues 183-198 of SEQ ID NO:66.
  • a linker can be composed of the following amino acid sequences: G(SGGGG) 2 SGGGLGSTEF (SEQ ID NO: 21), RSTSGLGGGS (GGGGS) 2 G (SEQ ID NO: 22), QLTSGLGGGS (GGGGS) 2 G (SEQ ID NO: 23) ), GGGS (SEQ ID NO: 24), GGGGS (SEQ ID NO: 25), SSSSG (SEQ ID NO: 26), GSGSA (SEQ ID NO: 27), GGSGGGGGGSGGGGSGGGGS (SEQ ID NO: 28), SSSSGSSSSGSSSSG (SEQ) ID NO: 29), GGSGAGSGSAGSGSA (SEQ ID NO: 30), GGSGGGGSGGGGSGG (SEQ ID NO: 31), SEQ ID NO: 72, amino acid residues 1420-1456, and the like.
  • a suitable cleavage site which necessarily introduces one or more irrelevant residues at the end of the expressed amino acid sequence without affecting the activity of the sequence of interest.
  • promote expression of a recombinant protein obtain a recombinant protein that is automatically secreted outside the host cell, or facilitate purification of the recombinant protein, it is often necessary to add some amino acids to the N-terminus, C-terminus of the recombinant protein or within the protein.
  • Other suitable regions for example, including but not limited to, suitable linker peptides, signal peptides, leader peptides, End extension, etc.
  • the amino terminus or carboxy terminus of the fusion protein herein may also contain one or more polypeptide fragments as a protein tag.
  • Any suitable label can be used in this article.
  • the tag may be FLAG (DYKDDDDK, SEQ ID NO: 32), HA, HA1, c-Myc, Poly-His, Poly-Arg, Strep-TagII, AU1, EE, T7, 4A6, ⁇ , B , gE and Ty1. These tags can be used to purify proteins.
  • the fusion proteins herein may also contain a nuclear localization sequence (NLS).
  • Nuclear localization sequences of various sources and various amino acids well known in the art can be used.
  • Such nuclear localization sequences include, but are not limited to, the NLS of the SV40 viral large T antigen having the amino acid sequence PKKKRKV (SEQ ID NO: 33); the NLS from the nuclear protein, for example, having the sequence KRPAATKKAGQAKKKK (SEQ ID NO: 34) Nuclear protein dichotomous NLS; NLS from c-myc having the amino acid sequence PAAKRVKLD (SEQ ID NO: 35) or RQRRNELRSRSP (SEQ ID NO: 36); NLS from hRNPA1M9 having the sequence NQSSNFGPMKGGNFGGRSSGPYGGGGQYFAKPRNQGGY (SEQ ID NO: 37); sequence from the IBB domain of the input protein- ⁇ RMRIZFKNKGKDTAELRRRRVEVSVELRKAKKDEQILK
  • the sequence shown by amino acid residues 26-33 of SEQ ID NO: 2 is used herein as the NLS.
  • the NLS may be located at the N-terminus and C-terminus of the fusion protein; it may also be located in the fusion protein sequence, such as the N-terminus and/or C-terminus of the Cas9 enzyme in the fusion protein, or the N-terminus and/or C of the AID located in the fusion protein. end.
  • the accumulation of the fusion protein of the invention in the nucleus can be detected by any suitable technique.
  • a detection marker can be fused to the Cas enzyme such that the location of the fusion protein within the cell can be visualized when combined with means for detecting the location of the nucleus (eg, a dye specific for the nucleus, such as DAPI).
  • 3*flag is used herein as a marker, and the peptide sequence can be as shown in amino acid residues 1-23 of SEQ ID NO:2. It will be understood that, in general, if a marker sequence is present, the marker sequence is typically at the N-terminus of the fusion protein.
  • the tag sequence can be directly linked to the NLS or can be joined by a suitable linker sequence.
  • the NLS sequence can be ligated directly to the Cas enzyme or AID, or it can be ligated to the Cas enzyme or AID by a suitable linker sequence.
  • the fusion proteins herein consist of a Cas enzyme and an AID.
  • the fusion protein herein is formed by the Cas enzyme linked to the AID via a linker.
  • the fusion protein NLS, Cas enzyme, AID, and optional linker sequences between the Cas enzyme and the AID are comprised herein.
  • the Cas enzyme in the fusion protein is a Cas9 enzyme as described hereinbefore.
  • the amino acid sequence of the AID in the fusion protein is set forth in amino acid residues 1457-1654 of SEQ ID NO:2.
  • amino acid sequence of the AID in the fusion protein is set forth in amino acid residues 1457-1646 of SEQ ID NO:4. In other specific embodiments, the amino acid sequence of the AID in the fusion protein is set forth in amino acid residues 1447-1629 of SEQ ID NO:68.
  • the amino acid sequence of the fusion protein herein is as set forth in SEQ ID NO: 2, 4, 66, 68, 70 or 72, or as shown in amino acids 26-1654 of SEQ ID NO: 2, or As shown in SEQ ID NO: 4, positions 26-1638, or as shown in SEQ ID NO: 68, amino acids 26-1629, or as SEQ ID NO: 70, amino acids 26-1629, or as SEQ ID NO: 72 is shown in amino acids 26-1638.
  • polynucleotide sequences encoding the fusion proteins herein may be in the form of DNA or RNA.
  • DNA forms include cDNA, genomic DNA or synthetic DNA.
  • DNA can be single-stranded or double-stranded.
  • the DNA can be a coding strand or a non-coding strand.
  • the nucleotide sequences described herein can generally be obtained by PCR amplification.
  • primers can be designed according to the nucleotide sequences disclosed herein, particularly the open reading frame sequences, and using a commercially available cDNA library or a cDNA library prepared by conventional methods known to those skilled in the art as a template, The relevant sequences were amplified. When the sequence is long, it is often necessary to perform two or more PCR amplifications, and then the amplified fragments are spliced together in the correct order.
  • the polynucleotide sequence encoding a fusion protein described herein is set forth in SEQ ID NO: 1, 3, 65, 67, 79 or 71, or as SEQ ID NO: 1 73-4965 Shown as a base, or as shown in bases 73-4917 of SEQ ID NO: 3, or as bases 76-4890 of SEQ ID NO: 67, or as SEQ ID NO: 70, 76- The 4890 bases are shown, or as shown in SEQ ID NO: 72, positions 76-4917.
  • nucleic acid constructs comprising the polynucleotides.
  • the nucleic acid construct contains the coding sequences for the fusion proteins described herein, as well as one or more regulatory sequences operably linked to the sequences.
  • the coding sequences for the fusion proteins of the invention can be manipulated in a variety of ways to ensure expression of the proteins.
  • the nucleic acid construct can be manipulated depending on the identity or requirements of the expression vector prior to insertion of the nucleic acid construct into the vector. Techniques for altering polynucleotide sequences using recombinant DNA methods are known in the art.
  • the control sequence can be a suitable promoter sequence.
  • the promoter sequence is typically operably linked to the coding sequence of the protein to be expressed.
  • the promoter may be any nucleotide sequence that exhibits transcriptional activity in the host cell of choice, including mutated, truncated and hybrid promoters, and may be derived from an extracellular or heterologous source encoding the host cell. Or Gene acquisition of intracellular polypeptides.
  • the control sequence may also be a suitable transcription terminator sequence, a sequence recognized by the host cell to terminate transcription.
  • the terminator sequence is operably linked to the 3' terminus of the nucleotide sequence encoding the polypeptide. Any terminator that is functional in the host cell of choice may be used in the present invention.
  • the control sequence may also be a suitable leader sequence, an untranslated region of the mRNA that is important for translation by the host cell.
  • the leader sequence is operably linked to the 5' terminus of the nucleotide sequence encoding the polypeptide. Any terminator that is functional in the host cell of choice may be used in the present invention.
  • the nucleic acid construct is a vector.
  • a polynucleotide sequence herein can be inserted into a recombinant expression vector.
  • recombinant expression vector refers to bacterial plasmids, phage, yeast plasmids, plant cell viruses, mammalian cell viruses such as adenoviruses, retroviruses or other vectors well known in the art. Any plasmid and vector can be used as long as it can replicate and stabilize in the host.
  • An important feature of expression vectors is that they typically contain an origin of replication, a promoter, a marker gene, and a translational control element.
  • the expression vector may also include a ribosome binding site for translation initiation and a transcription terminator.
  • the polynucleotide sequences described herein are operably linked to a suitable promoter in an expression vector to direct mRNA synthesis via the promoter.
  • suitable promoters are: lac or trp promoter of E. coli; lambda phage PL promoter; eukaryotic promoters include CMV immediate early promoter, HSV thymidine kinase promoter, early and late SV40 promoter, anti- Promoters for the expression of LTRs of transcriptional viruses and other known controllable genes in prokaryotic or eukaryotic cells or their viruses.
  • the marker gene can be used to provide phenotypic traits for selection of transformed host cells including, but not limited to, dihydrofolate reductase for eukaryotic cell culture, neomycin resistance, and green fluorescent protein (GFP), or for the large intestine Bacillus tetracycline or ampicillin resistance.
  • GFP green fluorescent protein
  • a polynucleotide described herein is expressed in a higher eukaryotic cell, transcription will be enhanced if an enhancer sequence is inserted into the vector.
  • An enhancer is a cis-acting factor of DNA, usually about 10 to 300 base pairs, acting on a promoter to enhance transcription of the gene.
  • Expression vectors containing the polynucleotide sequences described herein and appropriate transcription/translation control signals can be constructed using methods well known to those of skill in the art. These methods include in vitro recombinant DNA techniques, DNA synthesis techniques, in vivo recombinant techniques, and the like.
  • the vectors described herein can be transformed into a suitable host cell to enable expression of the fusion proteins described herein.
  • the host cell can be a prokaryotic cell, such as a bacterial cell; or a lower eukaryotic cell, such as a yeast cell; a filamentous fungal cell, or a higher eukaryotic cell, such as a mammalian cell.
  • the host cell can also be a plant cell.
  • host cells are: Escherichia coli; Streptomyces; bacterial cells of Salmonella typhimurium; fungal cells such as yeast, filamentous fungi; plant cells; insect cells of Drosophila S2 or Sf9; CHO, COS, 293 cells, Or animal cells of Bowes melanoma cells, etc.
  • others include A polynucleotide sequence or vector and a cell of sgRNA or an expression vector thereof, such as a cell for the preparation of a point mutant protein, are also within the scope of the host cells described herein.
  • Transformation of host cells with recombinant DNA can be carried out using conventional techniques well known to those skilled in the art.
  • the host is a prokaryote such as E. coli
  • competent cells capable of absorbing DNA can be harvested after the exponential growth phase and treated by the CaCl 2 method, and the procedures used are well known in the art.
  • Another method is to use MgCl 2 .
  • Conversion can also be carried out by electroporation if desired.
  • the host is a eukaryote, the following DNA transfection methods can be used: calcium phosphate coprecipitation, conventional mechanical methods such as microinjection, electroporation, liposome packaging, and the like.
  • the obtained transformant can be cultured in a conventional manner to allow it to express the fusion protein described herein.
  • the medium used in the culture may be selected from various conventional media depending on the host cell used.
  • the recombinant fusion proteins herein can be isolated and purified using various separation methods known in the art.
  • host cells comprising a fusion protein described herein, a coding sequence or expression vector thereof, and optionally sgRNA or an expression vector thereof, are also included herein.
  • Such host cells can constitutively express the fusion proteins described herein, and can also express the fusion proteins described herein under certain conditions of induction.
  • Methods for constitutively expressing a host cell or expressing a fusion protein of the invention under inducing conditions are well known in the art.
  • an expression vector of the invention is constructed using an inducible promoter to effect inducible expression of the fusion protein.
  • the fusion protein herein, its coding sequence or expression vector, and/and sgRNA, its coding sequence or expression vector can be provided in the form of a composition.
  • the composition may contain an expression vector for the fusion protein and sgRNA or sgRNA herein, or an expression vector containing the fusion protein herein and an expression vector for sgRNA or sgRNA.
  • the fusion protein or its expression vector, or sgRNA or its expression vector may be provided as a mixture, or may be packaged separately.
  • the composition may be in the form of a solution or it may be in a lyophilized form.
  • kits containing the compositions described herein comprising the expression vector of the fusion protein and sgRNA or sgRNA herein, or an expression vector comprising the expression vector of the fusion protein herein and sgRNA or sgRNA.
  • the fusion protein or its expression vector, or sgRNA or its expression vector can be packaged separately or in the form of a mixture.
  • reagents for transferring the fusion protein or its expression vector and/or sgRNA or expression vector thereof into a cell and instructions for directing the skilled person to perform the transfer.
  • the kit can also include instructions for the skilled artisan to practice the various methods and uses described herein using the components contained in the kit. Kit Other reagents, such as reagents for PCR, etc., are also included.
  • a third aspect herein provides a method of producing a point mutation in a cell, the method comprising the step of expressing a fusion protein and sgRNA described herein in said cell.
  • a fusion protein of the invention, or an expression vector thereof, and sgRNA or an expression vector thereof are introduced into the cell.
  • the cell constitutively expresses a fusion protein described herein only the corresponding sgRNA or its expression vector can be transferred into the cell.
  • the cells may also be incubated with the inducer after administration of the sgRNA, or the cells may be subjected to corresponding inducing measures (eg, illumination).
  • the fusion protein or its expression vector and/or sgRNA or expression vector thereof can be transferred into a cell using conventional transfection methods.
  • a plasmid DNA-liposome complex is first prepared, and then the plasmid DNA-liposome complex and the corresponding sgRNA are co-transfected into cells.
  • the cell can be cultured under conditions suitable for the growth of the cell and expression of a desired protein, and the resulting mutant can be isolated and analyzed by various conventional methods such as a high-throughput method.
  • the methods described herein for generating point mutations in cells can also be used to generate mutant libraries, and then the mutants in the library can be isolated and screened using conventional techniques to obtain mutants having the desired biological function. Accordingly, the invention also provides a method of constructing a mutant library, the method comprising the step of expressing a fusion protein and sgRNA described herein in said cell.
  • One or more sgRNAs can be designed for the same site to be mutated.
  • the target binding regions of the various sgRNAs designed are different, but have the same Cas protein recognition region.
  • the one or more sgRNAs can then be transferred into the cell along with the corresponding fusion protein.
  • the cell can be any cell of interest, including prokaryotic cells and eukaryotic cells, such as plant cells, animal cells, microbial cells, and the like. Particularly preferred are animal cells, such as mammalian cells, rodent cells, including humans, horses, cows, sheep, rats, rabbits, and the like.
  • Microbial cells include cells from a variety of microbial species well known in the art, especially those having microbial species of medical research value, production value (e.g., production of fuels such as ethanol, protein production, lipids such as DHA production).
  • the cells may also be cells of various organ origin, such as cells from human liver, kidney, skin, and the like.
  • the cells may also be various mature cell lines currently marketed, such as 293 cells, COS cells.
  • the cell is a cell from a healthy individual; in other embodiments, the cell is a cell from a diseased tissue of a diseased individual, such as a cell from an inflammatory tissue, a tumor cell, an induced pluripotent stem cell, and the like.
  • the cells may also be cells that have been genetically engineered to have a particular function (eg, to produce a protein of interest) or to produce a phenotype of interest.
  • the gene or nucleic acid sequence to be mutated may be naturally present in the cell for the cell (endogenous)
  • the gene or nucleic acid sequence may also be a foreign-transferred (exogenous) gene or nucleic acid sequence.
  • the extraneously transferred gene or nucleic acid sequence can be integrated into the genomic sequence of the cell or independently of the genome and stably expressed.
  • expression vectors expressing the fusion proteins and sgRNAs herein can be designed using known techniques to render these expression vectors suitable for expression in such cells.
  • a promoter that facilitates expression in the cell and other related regulatory sequences can be provided in an expression vector. These can be selected and implemented by the technician according to the actual situation.
  • Nucleic acid sequences which are expected to produce point mutations can be any nucleic acid sequence of interest, such as a gene sequence, particularly various diseases, or related to the production of various proteins of interest, or various biological functions of interest.
  • Such gene or nucleic acid sequences of interest include, but are not limited to, nucleic acid sequences encoding various functional proteins.
  • a functional protein refers to a protein capable of performing physiological functions of an organism, including a catalytic protein, a transport protein, an immune protein, and a regulatory protein.
  • the functional proteins include, but are not limited to, proteins involved in the development, progression, and metastasis of diseases, proteins involved in cell differentiation, proliferation, and apoptosis, proteins involved in metabolism, development-related proteins. , as well as various drug targets and so on.
  • the functional protein may be an antibody, an enzyme, a lipoprotein, a hormone protein, a transport and storage protein, a motor protein, a receptor protein, a membrane protein, or the like.
  • mutant libraries, polynucleotides, nucleic acid constructs, cells, methods, and the like, as described herein can be used to construct mutant libraries and further screen for proteins with new or greater functions, such as antibodies, enzymes, or other functional proteins. Wait.
  • Mutations can be made on the nucleic acid sequence of interest using the methods described herein, or at specific sites in the nucleic acid sequence of interest.
  • the PAM site on the template strand can be searched according to the Cas enzyme used, and the PAM site is immediately downstream of the PAM site or within 10 cells (for example, within 8, within 5 or 3).
  • a fragment of 15 to 25 bases in length, usually 18 to 22 bases in length, is designed as the target recognition region of the sgRNA to design the sgRNA recognized by the Cas enzyme.
  • a site that can serve as a PAM can be found near the specific site, and the Cas enzyme capable of recognizing the PAM can be selected according to the PAM, and the fusion protein of the present invention containing the Cas enzyme and correspondingly designed and prepared according to the description herein sgRNA.
  • the method herein may be an in vitro method or an in vivo method.
  • the fusion protein or expression vector thereof and sgRNA or expression vector thereof can be transferred into a subject, such as a corresponding tissue cell, by a means well known in the art, and the sensation can be screened by observing the phenotypic change of the animal.
  • a subject such as a corresponding tissue cell
  • the sensation can be screened by observing the phenotypic change of the animal.
  • a functional variant of interest it should be understood that in vivo experiments, the subject may be a variety of non-human animals, particularly various non-human model organisms conventionally employed in the art. In vivo experiments should also meet ethical requirements.
  • Example 1 Construction of pEntr11-dCas9-AID plasmid and pEntr11-dCas9-AIDX plasmid
  • a dCas9 gene fragment was amplified from dCas9 plasmid (Addgene) by PCR;
  • the TBi1CD was cloned into the pEntr11-dCas9 plasmid by the Gibson Assembly method, and the construction of the pEntr11-dCas9-TET1CD plasmid was completed.
  • the dCas9-AID fragment and the dCas9-AIDX fragment were amplified from the pEntr11-dCas9-AID plasmid and the pEntr11-dCas9-AIDX plasmid using the primers shown in SEQ ID NOS: 8 and 9 (Fig. 2, A);
  • the MO91 plasmid (Addgene Plasmid #19755) and the AID and AIDX fragments were digested with restriction endonucleases BglII and XhoI, and then the vector, AID fragment and AIDX fragment were recovered (Fig. 2, B);
  • the AID fragment and the AIDX fragment after digestion are ligated to the MO91 vector, and then the ligated product is transformed into Stbl3 competent cells;
  • Example 4 Establish an effective reporting system indicating the efficiency of AID point mutations
  • the level of point mutations at the genomic level needs to be detected by a simple and intuitive method.
  • the present invention mainly uses flow analysis techniques to indirectly detect the level of point mutations at the protein level.
  • the human insertion insertion stop codon (TAG) in the EGFP gene, EGFP could not be expressed normally.
  • TAG human insertion insertion stop codon
  • the fusion protein of this example acts on the stop codon in the EGFP gene, the stop codon is mutated and the EGFP gene mutation is normally expressed. Therefore, the higher the level of EGFP expression, the higher the efficiency of point mutations.
  • the EGFP gene containing the stop codon was inserted into the MO405-thy1.1 plasmid (Addgene), and MSCV initiated gene expression. Infecting 293T with this plasmid, specifically including:
  • the poisoning method is the same as the transfection method
  • sgRNA was cloned into pLX (Addgene 50662) to obtain pLX sgRNA.
  • the following four primers are required, wherein R1 and F2 are sgRNA specific:
  • R1 rc (GN 19) GGTGTTTCGTCCTTTCC (SEQ ID NO: 11)
  • R2 AAAGCTAGCTAATGCCAACTTTGTACAAGAAAGCTG (SEQ ID NO: 13)
  • GN 19 new target sequence
  • rc (GN 19 ) reverse complement of the new target sequence
  • the base sequences of the target binding regions of the four sgRNAs are as follows:
  • Example 6 CRISPR-Cas9 improves AID point mutation efficiency
  • Transfection was carried out by culturing the reporter cells constructed in Example 4 to a confluency of 70-90%.
  • transfected first prepare a plasmid DNA-liposome complex, including four times the amount 2000 reagent diluted in In the medium, dilute the MO91-dCas9 (3*flag, NLS)-AID plasmid or the MO91-dCas9 (3*flag, NLS)-AIDX plasmid, respectively.
  • the diluted plasmid is then separately added to the diluted Incubate for 30 minutes in 2000 reagents (1:1).
  • Example 4 The plasmid DNA-liposome complex and the 4 sgRNAs against the EGFP stop codon prepared in Example 5 were then co-transfected with the reporter cells constructed in Example 4.
  • the reporter cells constructed in Example 4 were transfected only with the plasmid DNA-liposome complex. Incubation was carried out by adding 2 ug/ml of puromycin and 20 ug/ml of blasticidin, and screening for 3d, and analyzing the expression level of EGFP on the 4th and 7th day after transfection, respectively.
  • the %EGFP+ of AID and AIDX were 0.14% and 0.30%, respectively.
  • the %EGFP+ of dCas9-AID+sgRNA and dCas9-AIDX+sgRNA were 2.14% and 4.36%, respectively.
  • Example 7 CRISPR-Cas9 improves AID point mutation efficiency and optimization
  • the expression vector of sgRNA and dCas9-AID was co-transduced in the reporter cells constructed in Example 4 in the same manner as in Example 6.
  • the sgRNA was divided into two groups, one of which was a control sgRNA against AAVS1, and the target binding regions thereof were as follows: GATTCCCAGGGCCGGTTAATG (SEQ ID NO: 18); GTCCCCTCCACCCCACAGTG (SEQ ID NO: 19); and GGGGCCACTAGGGACAGGAT (SEQ ID NO: 20).
  • the other group is the sgRNA group against EGFP (SEQ ID NOS: 14-17).
  • the control group was set to single-turn AID in the reporter cells.
  • An expression vector for the control sgRNA was constructed as described in Example 5.
  • dCas9 was fused to different AID mutants: AID-FL (full length), AID-CD (catalytic domain only), P182X (from amino acid residue 183) Short), R186X (truncated from amino acid residue at position 187), R190X (truncated from amino acid residue at position 191).
  • dCas9-AID expression vector and sgRNA were co-transformed in the reporter cells, with dCas9-R186X being the most efficient ( Figure 8, B and C).
  • the experiments of Examples 8-13 were therefore carried out using dCas9-R186X, and in these examples, dCas9-R186X was simply referred to as dCas9-AIDX.
  • the entire system has a base substitution function, and a functional mutant of Cas9, dCas9, dCas9-AIDX is separately co-transferred in the reporter cells [R186X(E58Q) ], dCas9-AIDX and sgRNA, only the dcas9-AIDX and sgRNA groups have EGFP%+, while the other groups are all 0 (Fig. 8, C). It also proves that it is indeed the fusion of AID and dCas9 that the entire system has a base replacement function.
  • Example 8 CRISPR-Cas9 limits AID point mutation to sgRNA targeting sites
  • Example 9 dCas9-AIDX randomly mutates C and G bases to three other bases
  • AIDX itself will mutate C to T and G to A. After the fusion of dCas9 and AIDX, the mutation direction of C and G became more uniform compared with the AIDX group.
  • the role of the AID itself is dependent on the WRCY of the hotspot motif (W stands for A/T, R stands for A/C, Y stands for C/T), and the most preferred motif is AGCT.
  • W stands for A/T
  • R stands for A/C
  • Y stands for C/T
  • the most preferred motif is AGCT.
  • the inventors have proposed a hypothesis that under normal circumstances, AID will deamination of cytosine to form uracil, which is repaired by DNA replication, and this ug mismatch is retained, and mutations of C to T and G to A occur, and The U base can be excised by base excision repair, and then four bases are inserted. Therefore, the fusion of dCas9 and AID is likely to inhibit the DNA replication pathway, promote base excision repair, and make the mutation direction more uniform (Fig. 10, b).
  • Example 10 UGI increases the base substitution frequency of the dCas9-AIDX system, reveals the trajectory of dCas9-AIDX on the gene, and makes the base mutation direction more singular.
  • UGI is an inhibitor of UNG, a phage protein that protects its genome from host UNG when it invades E. coli (Fig. 11, a).
  • Three plasmids were co-transduced in the reporter cells, expressing dCas9-AIDX, a single sgRNA (target binding region GCCTCGAACTTCACCTCGGCG, SEQ ID NO: 16) and UGI (protein sequence: UniProtKB-P14739) to enhance a single sgRNA throughout the system. Mutation efficiency. The results showed a 10-fold increase in the highest point mutation efficiency (Fig. 11, b).
  • Figure 11 (c) is a statistic based on data for 4 sgRNAs designed for the EGFP site.
  • N is the first base in NGG in the PAM sequence.
  • the upstream is -, the downstream is +, the statistical results of the two sets of data are consistent, both of which cause mutations in the upstream 20 bp of the PAM, that is, in the prototype interval region, and the highest point of mutation is in the -12/-13 position of the PAM.
  • UGI can increase the overall mutation frequency of AID, but it will increase the proportion of base substitutions and reduce the conversion ratio (Fig. 11, d).
  • Example 11 dCas9-AIDX can act not only on exogenous genes, but also on endogenous genes.
  • the above experiments were all carried out in the reporter cells.
  • the endogenous gene AAVS1 was selected as the target site, and three sgRNAs (SEQ ID NO: 18-20) were designed, and dCas9-AID and AAVS1 were co-transduced in 293T.
  • the vector of three sgRNAs (as described in Example 7).
  • the dCas9-AID system can also generate base substitutions to the endogenous gene AAVS1, and this mutation is also concentrated in the sgRNA target site.
  • Example 12 Application of dCas9-AIDX to Gleevec resistance screening of K562BCR-ABL gene
  • K562 is a leukemia cell line derived from human chronic myeloid leukemia. There is a chromosome in this cell called the ph chromosome. The chromosome is transposed by the long arms of chromosomes 9 and 22.
  • the ABL gene on chromosome 9 contains a tyrosine kinase active center, which is in a low activity state under normal conditions, and has a high activity when translocated into the BCR locus.
  • BCR-ABL is a proto-oncogene
  • the commonly used drug is Gleevec (Gleevec, the active ingredient is imatinib mesylate)
  • the main mechanism of action is gleevec ATP can be competitively bound to ABL, resulting in a low activity of the ABL gene.
  • point mutations such as T315I
  • T315I point mutations, such as T315I
  • base substitutions at other sites can also cause Gleevec resistance.
  • the dCas9-AIDX system can be used to screen for Gleevec resistance sites and specific mutation types as a basis for designing next generation inhibitors.
  • the cells were cultured with 2 ml of anti-seeding solution, and virus was collected at 48 hours and 72 hours, respectively. Good collection 1000rpm virus immediate cell debris was removed by centrifugation for 5 minutes, the supernatant was added 2ul 10mg / ml Polybrene of infection 1x10 5 K562 cells, 37 °C, 900g speed rejection board 90 minutes. The cells were centrifuged 4 hours after infection, and the pellet was cultured with an anti-seeding solution. After two days of continuous infection, K562 cells need to be cultured for another two days. Flow cytometry is used to label cells expressing Thy1.1 surface molecules as PE + (antibody 1:200 dilution) and using single cell sorting technique.
  • PE + antibody 1:200 dilution
  • RNA of the cell population produced by each single cell clone was collected and subjected to RT-qPCR experiments.
  • the cell line with the highest expression of dCas9-AIDX was used for subsequent screening of Gleevec resistance sites and mutation types.
  • sgRNA for the genomic region of Exon6, the sixth exon of ABL gene.
  • a total of 16 sgRNAs were designed (target sequence sequences are shown in SEQ ID NOs: 49-64, respectively), of which 6 are targeted to intron regions adjacent to exon Exon6, and 10 are directly targeted to the Exon6 region. And covered 83% of the exon sequences. Since the mutation of T315I has been recognized as one of the most important mutations causing Gleevec resistance, one and only one of the sgRNAs we designed can cover the T315I mutation site (944C) and can be used as a positive control.
  • sgRNAs as negative controls for the genomic sequence of the AAVS1 gene unrelated to Gleevec resistance (target sequence sequences are shown in SEQ ID NOs: 18-20). These sgRNA sequences were all chemically synthesized, digested with BamH1 and HindIII, and finally cloned into the pSUPER-sgRNA vector carrying the H1 promoter.
  • the K562 cell line stably expressing dCas9-AIDX was electroporated with ABL-Exon6 and AAVS1 mixed sgRNA libraries, respectively, and the instrument was used by the American Life Technology company Neoelectric transducer. 12-24 hours before electroporation, K562 cells were cultured in IMDM medium without anti-10% FBS. On the day of electroporation, two 1.2 ⁇ 10 6 K562 cells were transfected with 8ug respectively on the condition of 1000V voltage, single pulse and 50ms shock time. Equally mixed ABL-Exon6 or AAVS1 sgRNA.
  • pSUPER-sgRNA plasmid vector carries the puromycin resistance gene
  • cells expressing sgRNA were screened 24 hours after transfection by adding 2 ug/ml puromycin. After treatment with puromycin for 48 hours, K562 cells continued to expand.
  • 2x10 5 of cellular DNA and RNA were collected for high-throughput sequencing and used as an Input control. The remaining cells were split into two portions and treated with 10 uM Gleevec drug or with an equal volume of DMSO, respectively. Once every three days Ficoll, remove dead cells, until the cell number far lower than when 2x10 4.
  • Example 13 Application of dCas9-AIDX to increase the affinity and specificity of antibodies in vitro
  • Antibodies can specifically recognize antigens as drug proteins for the treatment of various diseases.
  • the affinity of an antibody is directly proportional to the somatic mutations produced in the germinal center in vivo.
  • high affinity antibodies have multiple somatic high frequency mutations. Therefore, dCas9-AIDX can be used to mutate antibody genes to screen for antibodies with stronger affinity or other characteristics (such as better specificity, etc.).
  • the protocol is as follows.
  • the antibody molecule is stably expressed on the surface of 293T cells, and then sgRNA is designed for the antibody gene, and 293T cells are simultaneously transfected with dCas9-AIDX, and then the cell surface is stained. The stronger the stained cells, the mutant antibody molecules have Stronger affinity.
  • the present embodiment employs from Invitrogen stably expressing Flp-In TM -293 lacZ-ZeocinTM a cell fusion locus.
  • the transmembrane region sequence of the protein was cloned into a cDNA sequence such as pcDNA5/FRT/GOI vector (Life Science Technology, USA).
  • the vector into Flp-InMM-293 cells using the Flp-In TM system Flp-In TM -293 cells contained the coding sequence containing the IgG1 Flp recombinase integrated into the target site by Flp recombinase lacZ- ZeocinTM fusion locus.
  • Cells that were not successfully integrated were able to express anti-Zeocin proteins; after successful integration, anti-Zeocin proteins could not be expressed due to the lack of the initiation codon ATG, but were able to express hygromycin-resistant proteins. Therefore, hygromycin antibiotics were used to screen for IgG1-synthesized 293 cells in which only one copy of the anti-HEL-IgG1 gene was expressed per cell.
  • the sgRNA sequence was then cloned into the pSUPER-puro plasmid vector (Addgene).
  • the MO91-dCas9 (3*flag, NLS)-AIDX plasmid constructed in Example 3 and the sgRNA library (ie, 16 sgRNAs were mixed together in equal amounts) or the sgRNA of the control gene AAVS1 were co-transfected into the IgG1-expressing IgG1 obtained previously.
  • the sgRNA library ie, 16 sgRNAs were mixed together in equal amounts
  • the sgRNA of the control gene AAVS1 were co-transfected into the IgG1-expressing IgG1 obtained previously.
  • PE anti-mouse IgG and Alex647-HEL were stained on the 7th day after transfection, and then flow sorted to sort out IgG strength. Cells that are unchanged and bind to the HEL antigen.
  • mutant cells were detected by flow cytometry using PE anti-mouse IgG1 and 647-HEL surface staining, and it was found that a small group of cells had unchanged IgG1 expression and increased binding to HEL. This group of cells was then subjected to flow sorting, and after sorting and amplification, compared with the cells before the mutation, it was found that the affinity of the mutant antibody to HEL was enhanced more than 10 times (Fig. 17).
  • MO91-AIDX-XTEN-dCas9 MO91-dCas9-XTEN-AIDX (K10E T82I E156G) and MO91-nCas9-AIDX can be constructed by referring to the above steps and the methods of Examples 1 and 2.
  • the 3*flag and/or NLS fragment can be cloned into the above plasmid by the method of Example 3 to obtain SEQ ID NO: 66, 68, 70 and 72, respectively.
  • the AIDX in these fusion proteins is an AID fragment or a mutant thereof truncated from amino acid residue 183.
  • the resulting expression strain was grown overnight in LB medium containing 100 ⁇ g/ml kanamycin at 37 °C.
  • the culture was cooled to 4 ° C in 2 hours, IPTG 0.5 mM was added, and the protein expression was induced for ⁇ 16 h;
  • His-tagged fusion protein was eluted in elution buffer and concentrated to a total volume of 1 ml by ultrafiltration (Amicon-Millipore, 100 kDa molecular weight cut-off);
  • the protein was diluted to 20 ml in buffer A and loaded onto a Hi-Trap SP column (29051324, GE Healthcare) and eluted with a gradient of 100 mM-1 M NaCl;

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Genetics & Genomics (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Wood Science & Technology (AREA)
  • Zoology (AREA)
  • Biochemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • General Health & Medical Sciences (AREA)
  • Molecular Biology (AREA)
  • Biomedical Technology (AREA)
  • Biotechnology (AREA)
  • Microbiology (AREA)
  • Medicinal Chemistry (AREA)
  • Biophysics (AREA)
  • Physics & Mathematics (AREA)
  • Plant Pathology (AREA)
  • Proteomics, Peptides & Aminoacids (AREA)
  • Micro-Organisms Or Cultivation Processes Thereof (AREA)
  • Peptides Or Proteins (AREA)
  • Enzymes And Modification Thereof (AREA)

Abstract

L'invention concerne une protéine de fusion produisant une mutation ponctuelle dans une cellule, ainsi que sa préparation et son utilisation. La protéine de fusion comprend ou est formée par une cytosine désaminase et une enzyme Cas dans laquelle l'activité nucléase est déficiente mais l'activité hélicase est conservée. L'invention concerne également la séquence codante pour la protéine de fusion, une séquence polynucléotidique contenant la séquence codante, une construction d'acide nucléique contenant la séquence polynucléotidique, la cellule hôte correspondante, un procédé de production de la mutation ponctuelle dans la cellule, et un kit, etc. Le procédé permet d'obtenir une mutagenèse dirigée, et en même temps, d'obtenir une efficacité de mutation élevée et de multiples combinaisons de mutations dans une région de gène particulière.
PCT/CN2017/088369 2016-06-15 2017-06-15 Protéine de fusion produisant une mutation ponctuelle dans une cellule, sa préparation et son utilisation WO2017215619A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201610423512.8 2016-06-15
CN201610423512 2016-06-15

Publications (1)

Publication Number Publication Date
WO2017215619A1 true WO2017215619A1 (fr) 2017-12-21

Family

ID=60663317

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2017/088369 WO2017215619A1 (fr) 2016-06-15 2017-06-15 Protéine de fusion produisant une mutation ponctuelle dans une cellule, sa préparation et son utilisation

Country Status (2)

Country Link
CN (2) CN114380922A (fr)
WO (1) WO2017215619A1 (fr)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108504676A (zh) * 2018-02-05 2018-09-07 上海科技大学 一种pnCasSA-BEC质粒及其应用
CN109593781A (zh) * 2018-12-20 2019-04-09 华中农业大学 陆地棉基因组的精准高效编辑方法
CN112480262A (zh) * 2019-09-11 2021-03-12 中国科学院沈阳应用生态研究所 一种融合蛋白及其制备与应用
WO2022047624A1 (fr) * 2020-09-01 2022-03-10 Huigene Therapeutics Co., Ltd Petites protéines cas et leurs utilisations
CN115850385A (zh) * 2022-07-04 2023-03-28 北京惠之衡生物科技有限公司 一种促表达肽及其应用
WO2023160163A1 (fr) * 2022-02-22 2023-08-31 中国科学院深圳先进技术研究院 Procédé de détection de la position de liaison d'une protéine et d'un désoxyribonucléotide in situ
WO2024069581A1 (fr) * 2022-09-30 2024-04-04 Illumina Singapore Pte. Ltd. Complexes hélicase-cytidine désaminase et procédés d'utilisation

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110527697B (zh) * 2018-05-23 2023-07-07 中国科学院分子植物科学卓越创新中心 基于CRISPR-Cas13a的RNA定点编辑技术
CN110938658B (zh) * 2018-09-21 2023-02-07 中国科学院分子细胞科学卓越创新中心 一种抗体进化方法及其应用
CN109402096B (zh) * 2018-11-20 2021-01-01 中国科学院生物物理研究所 一种aid酶突变体及其应用
CN111748546B (zh) * 2019-03-26 2023-05-09 复旦大学附属中山医院 一种产生基因点突变的融合蛋白及基因点突变的诱导方法
CA3139581A1 (fr) * 2019-05-03 2020-11-12 Specific Biologics Inc. Endonuclease a double clivage encapsulee dans des lipides pour adn et gene
CN111304180B (zh) * 2019-06-04 2023-05-26 山东舜丰生物科技有限公司 一种新的dna核酸切割酶及其应用
JP2023508669A (ja) * 2019-12-26 2023-03-03 エージェンシー フォー サイエンス, テクノロジー アンド リサーチ 核酸塩基エディター
CN111518794B (zh) * 2020-04-13 2023-05-16 中山大学 基于激活诱导性胞苷脱氨酶的诱导突变蛋白的制备和用途
CN113773373B (zh) * 2021-10-12 2024-02-06 成都齐碳科技有限公司 孔蛋白单体的突变体、蛋白孔及其应用
CN113896776B (zh) * 2021-10-12 2024-02-06 成都齐碳科技有限公司 孔蛋白单体的突变体、蛋白孔及其应用

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015089406A1 (fr) * 2013-12-12 2015-06-18 President And Fellows Of Harvard College Variantes genetiques de cas pour l'edition genique
WO2015133554A1 (fr) * 2014-03-05 2015-09-11 国立大学法人神戸大学 Procédé de modification de séquence génomique permettant la conversion de façon spécifique de bases d'acide nucléique de séquences d'adn ciblées et complexe moléculaire destiné à être utilisée dans ce dernier
WO2016022363A2 (fr) * 2014-07-30 2016-02-11 President And Fellows Of Harvard College Protéines cas9 comprenant des intéines dépendant de ligands
CN105518146A (zh) * 2013-04-04 2016-04-20 哈佛学院校长同事会 利用CRISPR/Cas系统的基因组编辑的治疗性用途

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2636075C (fr) * 2006-01-03 2011-11-08 F. Hoffmann-La Roche Ag Proteine de fusion chimerique d'activites chaperone et de repliement superieures
CN108291218B (zh) * 2015-07-15 2022-08-19 新泽西鲁特格斯州立大学 核酸酶非依赖性靶向基因编辑平台及其用途

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105518146A (zh) * 2013-04-04 2016-04-20 哈佛学院校长同事会 利用CRISPR/Cas系统的基因组编辑的治疗性用途
WO2015089406A1 (fr) * 2013-12-12 2015-06-18 President And Fellows Of Harvard College Variantes genetiques de cas pour l'edition genique
WO2015133554A1 (fr) * 2014-03-05 2015-09-11 国立大学法人神戸大学 Procédé de modification de séquence génomique permettant la conversion de façon spécifique de bases d'acide nucléique de séquences d'adn ciblées et complexe moléculaire destiné à être utilisée dans ce dernier
WO2016022363A2 (fr) * 2014-07-30 2016-02-11 President And Fellows Of Harvard College Protéines cas9 comprenant des intéines dépendant de ligands

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
LEE, C.M. ET AL.: "The Neisseria Meningitidis CRISPR-Cas9 System Enables Specific Genome Editing in Mammalian Cells", MOLECULAR THERAPY, vol. 24, no. 3, 16 February 2016 (2016-02-16), pages 645 - 654, XP055449590 *
MA, Y.Q. ET AL.: "Targeted AID-Mediated Mutagenesis (TAM) Enables Efficient Genomic Diversification in Mammalian Cells", NATURE METHODS, vol. 13, no. 12, 10 October 2016 (2016-10-10), pages 1029 - 1035, XP002778319 *

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108504676A (zh) * 2018-02-05 2018-09-07 上海科技大学 一种pnCasSA-BEC质粒及其应用
CN108504676B (zh) * 2018-02-05 2021-12-10 上海科技大学 一种pnCasSA-BEC质粒及其应用
CN109593781A (zh) * 2018-12-20 2019-04-09 华中农业大学 陆地棉基因组的精准高效编辑方法
CN112480262A (zh) * 2019-09-11 2021-03-12 中国科学院沈阳应用生态研究所 一种融合蛋白及其制备与应用
CN112480262B (zh) * 2019-09-11 2022-10-28 中国科学院沈阳应用生态研究所 一种融合蛋白及其制备与应用
WO2022047624A1 (fr) * 2020-09-01 2022-03-10 Huigene Therapeutics Co., Ltd Petites protéines cas et leurs utilisations
WO2023160163A1 (fr) * 2022-02-22 2023-08-31 中国科学院深圳先进技术研究院 Procédé de détection de la position de liaison d'une protéine et d'un désoxyribonucléotide in situ
CN115850385A (zh) * 2022-07-04 2023-03-28 北京惠之衡生物科技有限公司 一种促表达肽及其应用
CN115850385B (zh) * 2022-07-04 2023-08-11 北京惠之衡生物科技有限公司 一种促表达肽及其应用
WO2024069581A1 (fr) * 2022-09-30 2024-04-04 Illumina Singapore Pte. Ltd. Complexes hélicase-cytidine désaminase et procédés d'utilisation

Also Published As

Publication number Publication date
CN107522787A (zh) 2017-12-29
CN114380922A (zh) 2022-04-22

Similar Documents

Publication Publication Date Title
WO2017215619A1 (fr) Protéine de fusion produisant une mutation ponctuelle dans une cellule, sa préparation et son utilisation
JP6892642B2 (ja) 光依存的に又は薬物存在下でヌクレアーゼ活性若しくはニッカーゼ活性を示す、又は標的遺伝子の発現を抑制若しくは活性化するポリペプチドのセット
CN107794272B (zh) 一种高特异性的crispr基因组编辑体系
US11162084B2 (en) Enhanced hAT family transposon-mediated gene transfer and associated compositions, systems, and methods
US7244609B2 (en) Synthetic genes and bacterial plasmids devoid of CpG
KR20210056329A (ko) 신규 cas12b 효소 및 시스템
JP6502259B2 (ja) 部位特異的酵素および使用方法
CN114729368A (zh) 用于免疫疗法的组合物和方法
JP2016523084A (ja) 標的組込み
JP2009017884A (ja) 染色体に基くプラットホーム
JPH04505104A (ja) 相同組換え法を用いてのタンパク質の生成
JP6956416B2 (ja) トランスポゾン系、それを含むキット及びそれらの使用
JP2022070950A (ja) 生合成経路を発現する合成染色体の作成方法及びその使用
EP3810764A2 (fr) Transfert amélioré de gènes médié par transposon de la famille hat et compositions, systèmes et méthodes associés
CN109295053A (zh) 通过诱导剪接位点碱基突变或多聚嘧啶区碱基置换调控rna剪接的方法
JP2023156365A (ja) Crispr/cas融合タンパク質およびシステム
EP4349979A1 (fr) Nucléase cas12i modifiée, protéine effectrice et utilisation de celle-ci
JP2009538144A (ja) 真核細胞株を用いたタンパク質産生
US20210403924A1 (en) Method for selecting cells based on CRISPR/Cas-mediated integration of a detectable tag to a target protein
JP3844656B2 (ja) 動物細胞の形質転換のための方法
CN115244177A (zh) 用于基因组修饰的高保真SpCas9核酸酶
JP2011504741A (ja) 新規組換え配列
JP7026304B2 (ja) 部位特異的dna開裂及び修復による標的化原位置タンパク質多様化
TWI260346B (en) Internal ribosome entry site of the labial gene for protein expression
JP2006510358A (ja) invivo親和性成熟系

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 17812730

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 17812730

Country of ref document: EP

Kind code of ref document: A1