Methods for genomic integration
Provided herein are methods of integrating one or more exogenous nucleic acids into one or more selected target sites of a host cell genome. In certain embodiments, the methods comprise contacting the host cell genome with one or more integration polynucleotides comprising an exogenous nucleic acid to be integrated into a genomic target site, a nuclease capable of causing a break at the genomic target site, and a linear nucleic acid capable of homologous recombination with itself or with one or more additional linear nucleic acids contacted with the population of cells, whereupon said homologous recombination results in formation of a circular extrachromosomal nucleic acid comprising a coding sequence for a selectable marker. In some embodiments, the methods further comprise selecting a host cell that expresses the selectable marker.
1. A host cell comprising:
(i) an exogenous nucleic acid (ES) capable of recombining, via homologous recombination, at a target site (TS) of the host cell genome;
(ii) a nuclease (N) capable of generating a break at TS; and
(iii) a nucleic acid that is introduced into the host cell as a linear nucleic acid and is capable of homologous recombination with itself or with one or more additional linear nucleic acid within the host cell, whereupon said homologous recombination results in formation of a circular extrachromosomal nucleic acid comprising a coding sequence for a selectable marker.
2. The host cell of claim 1 , wherein the linear nucleic acid comprises two internal homology regions that are capable of homologously recombining with each other, whereupon homologous recombination of the internal homology regions results in formation of the circular extrachromosomal nucleic acid expressing the selectable marker.
3. The host cell of claim 1 , wherein the linear nucleic acid comprises a homology region that is capable of recombining with a homology region of an additional linear nucleic acid within the host cell, whereupon homologous recombination of the two linear nucleic acids results in formation of the circular extrachromosomal nucleic acid expressing the selectable marker.
4. The host cell of claim 1 , wherein the linear nucleic acid comprises a partial, interrupted and/or non-contiguous coding sequence for the selectable marker, wherein the selectable marker cannot be expressed from the linear nucleic acid, whereupon said formation of the circular extrachromosomal nucleic acid results in formation of a complete coding sequence of the selectable marker, wherein the selectable marker can be expressed from the circular extrachromosomal nucleic acid.
5. The host cell of claim 1 , wherein the host cell comprises:
(i) a plurality of exogenous nucleic acids, wherein
x is an integer that varies from 1 to n, and for each integer x, each exogenous nucleic acid (ES) x is capable of recombining, via homologous recombination, at a target site (TS) x selected from said plurality of (n) target sites of said host cell genome;
(ii) for each said target site (TS) x , a nuclease (N) x capable of generating a break at (TS) x .
6. The host cell of claim 1 , wherein ES comprises a first homology region (HR1) and a second homology region (HR2), wherein HR1 and HR2 are capable of recombining, via homologous recombination, with a third homology region (HR3) and a fourth homology region (HR4), respectively, wherein HR3 and HR4 are each at TS.
7. The host cell of claim 1 , wherein N is capable of generating a single stranded break or a double stranded break at TS.
8. The host cell of claim 1 , wherein ES further comprises a nucleic acid of interest D.
9. The host cell of claim 8 , wherein D is selected from the group consisting of a selectable marker, a promoter, a nucleic acid sequence encoding an epitope tag, a gene of interest, a reporter gene, and a nucleic acid sequence encoding a termination codon.
10. The host cell of claim 1 , wherein ES is linear.
11. The host cell of claim 1 , wherein the circular extrachromasomal nucleic acid further comprises a coding sequence for the nuclease.
12. The host cell of claim 1 , wherein the nuclease is an RNA-guided DNA endonuclease.
13. The host cell of claim 12 , wherein the RNA-guided DNA endonuclease is a Cas9 endonuclease.
14. The host cell of claim 12 , wherein the circular extrachromosomal nucleic acid further comprises a sequence that encodes a crRNA activity and a tracrRNA activity that enables site-specific recognition and cleavage of TS by the RNA-guided DNA endonuclease.
15. The host cell of claim 14 , wherein the crRNA activity and the tracrRNA activity are expressed as a single contiguous RNA molecule.
16. The host cell of claim 1 , wherein the nuclease is selected from the group consisting of an endonuclease, a zinc finger nuclease, a TAL-effector DNA binding domain-nuclease fusion protein (TALEN), a transposase, and a site-specific recombinase.
17. The host cell of claim 16 , wherein the zinc finger nuclease is a fusion protein comprising the cleavage domain of a TypeIIS restriction endonuclease fused to an engineered zinc finger binding domain.
18. The host cell of claim 17 , wherein the TypeIIS restriction endonuclease is selected from the group consisting of HO endonuclease and Fok I endonuclease.
19. The host cell of claim 17 , wherein the zinc finger binding domain comprises 3, 5 or 6 zinc fingers.
20. The host cell of claim 17 , wherein the endonuclease is a homing endonuclease selected from the group consisting of: an LAGLIDADG (SEQ ID NO: 1) homing endonuclease, an HNH homing endonuclease, a His-Cys box homing endonuclease, a GIY-YIG homing endonuclease, and a cyanobacterial homing endonuclease.
21. The host cell of claim 17 , wherein the endonuclease is selected from the group consisting of: H-DreI, I-SceI, I-SceII, I-SceIII, I-SceIV, I-SceV, I-SceVI, I-SceVII, I-CeuI, I-CeuAIIP, I-CreI, I-CrepsbIP, I-CrepsbIIP, I-CrepsbIIIP, I-CrepsbIVP, I-TliI, I-PpoI, Pi-PspI, F-SceI, F-SceII, F-SuvI, F-CphI, F-TevI, F-TevII, I-AmaI, I-AniI, I-ChuI, I-CmoeI, I-CpaI, I-CpaII, I-CsmI, I-CvuI, I-CvuAIP, I-DdiI, I-DdiII, I-DirI, I-DmoI, I-HmuI, I-HmuII, I-HsNIP, I-LlaI, I-MsoI, I-NaaI, I-NanI, I-NclIP, I-NgrIP, I-NitI, I-NjaI, I-Nsp236IP, I-PakI, I-PboIP, I-PcuIP, I-PcuAI, I-PcuVI, I-PgrIP, I-PobIP, I-PorI, I-PorIIP, I-PbpIP, I-SpBetaIP, I-ScaI, I-SexIP, I-SneIP, I-SpomI, I-SpomCP, I-SpomIP, I-SpomIIP, I-SquIP, I-Ssp68031, I-SthPhiJP, I-SthPhiST3P, I-SthPhiSTe3bP, I-TdeIP, I-TevI, I-TevII, I-TevIII, i-UarAP, i-UarHGPAIP, I-UarHGPA13P, I-VinIP, I-ZbiIP, PI-MgaI, PI-MtuI, PI-MtuHIP PI-MtuHIIP, PI-PfuI, PI-PfuII, PI-PkoI, PI-PkoII, PI-Rma43812IP, PI-SpBetaIP, PI-SceI, PI-TfuI, PI-TfuII, PI-ThyI, PI-TliI, or PI-TliII.
22. The host cell of claim 17 , wherein the endonuclease is modified to specifically bind an endogenous genomic sequence, wherein the modified endonuclease no longer binds to its wild type endonuclease recognition sequence.
23. The host cell of claim 22 , wherein the modified endonuclease is derived from a homing endonuclease selected from the group consisting of: an LAGLIDADG (SEQ ID NO: 1) homing endonuclease, an HNH homing endonuclease, a His-Cys box homing endonuclease, a GIY-YIG homing endonuclease, and a cyanobacterial homing endonuclease.
24. The host cell of claim 22 , wherein the modified endonuclease is derived from an endonuclease selected from the group consisting of: H-DreI, I-SceI, I-SceII, I-SceIII, I-SceIV, I-SceV, I-SceVI, I-SceVII, I-CeuI, I-CeuAIIP, I-CreI, I-CrepsbIP, I-CrepsbIIP, I-CrepsbIIIP, I-CrepsbIVP, I-TliI, I-PpoI, Pi-PspI, F-SceI, F-SceII, F-SuvI, F-CphI, F-TevI, F-TevII, I-AmaI, I-AniI, I-ChuI, I-CmoeI, I-CpaI, I-CpaII, I-CsmI, I-CvuI, I-CvuAIP, I-DdiI, I-DdiII, I-DirI, I-DmoI, I-HmuI, I-HmuII, I-HsNIP, I-LlaI, I-MsoI, I-NaaI, I-NanI, I-NclIP, I-NgrIP, I-NitI, I-NjaI, I-Nsp236IP, I-PakI, I-PboIP, I-PcuIP, I-PcuAI, I-PcuVI, I-PgrIP, I-PobIP, I-PorI, I-PorIIP, I-PbpIP, I-SpBetaIP, I-ScaI, I-SexIP, I-SneIP, I-SpomI, I-SpomCP, I-SpomIP, I-SpomIIP, I-SquIP, I-Ssp68031, I-SthPhiJP, I-SthPhiST3P, I-SthPhiSTe3bP, I-TdeIP, I-TevI, I-TevII, I-TevIII, i-UarAP, i-UarHGPAIP, I-UarHGPA13P, I-VinIP, I-ZbiIP, PI-MgaI, PI-MtuI, PI-MtuHIP PI-MtuHIIP, PI-PfuI, PI-PfuII, PI-PkoI, PI-PkoII, PI-Rma43812IP, PI-SpBetaIP, PI-SceI, PI-TfuI, PI-TfuII, PI-ThyI, PI-TliI, or PI-TliII.
25. A host cell comprising:
an exogenous nucleic acid (ES) capable of recombining, via homologous recombination, at the target site (TS) of the host cell genome; and
(ii) a nucleic acid that is introduced into the host cell as a linear nucleic acid and is capable of homologous recombination with itself or with one or more additional linear nucleic acids contacted with the host cell, whereupon said homologous recombination results in formation of a circular extrachromosomal nucleic acid comprising a coding sequence for a selectable marker and a coding sequence for a nuclease (N) capable of generating a break at TS.
26. A method for integrating an exogenous nucleic acid into a target site of a host cell genome, the method comprising:
(a) contacting one or more host cells with:
(i) an exogenous nucleic acid (ES) capable of recombining, via homologous recombination, at the target site (TS) of the host cell genome;
(ii) a nuclease (N) capable of generating a break at TS; and
(iii) a linear nucleic acid capable of homologous recombination with itself or with one or more additional linear nucleic acids contacted with the host cell, whereupon said homologous recombination results in formation of a circular extrachromosomal nucleic acid comprising a coding sequence for a selectable marker;
and
(b) selecting a host cell that expresses the selectable marker,
wherein the linear nucleic acid comprises a partial, interrupted and/or non-contiguous coding sequence for the selectable marker, wherein the selectable marker cannot be expressed from the linear nucleic acid, whereupon said formation of the circular extrachromosomal nucleic acid results in formation of a complete coding sequence of the selectable marker, wherein the selectable marker can be expressed from the circular extrachromosomal nucleic acid.