Anti-CRISPR protein applications: natural brakes for CRISPR-Cas technologies


Clustered, regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) genes, a diverse family of prokaryotic adaptive immune systems, have emerged as a biotechnological tool and therapeutic. The discovery of protein inhibitors of CRISPR-Cas systems, called anti-CRISPR (Acr) proteins, enables the development of more controllable and precise CRISPR-Cas tools. Here we discuss applications of Acr proteins for post-translational control of CRISPR-Cas systems in prokaryotic and mammalian cells, organisms and ecosystems.

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Fig. 1: Stages of CRISPR-Cas immunity and mechanisms of Acr function.
Fig. 2: Applications of acr genes in prokaryotes.
Fig. 3: Applications and regulation of Acr proteins.
Fig. 4: Use of Acr proteins for controlling gene drives.


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We thank M. Pinilla-Redondo, who made the figures for this manuscript. Acr research in the Bondy-Denomy lab was supported by the University of California San Francisco Program for Breakthrough in Biomedical Research, funded in part by the Sandler Foundation, by an NIH Office of the Director Early Independence Award DP5-OD021344, by NIH R01GM127489, and by DARPA HR0011-17-2-0043. N.D.M. was supported by NIH F32GM133127, B.C. was supported by the Eötvös National Scholarship of Hungary and a Marie Skłodowska-Curie Actions Individual Global Fellowship (number 844093) of the Horizon 2020 Research Program of the European Commission. R.P.R. was funded by Joint Programming Initiative-Antimicrobial Resistance (JIP-AMR; DARWIN project, #7044-00004B), the Innovation Fund Denmark (Trojan Horse Project, #5157-00005B).

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N.D.M. wrote the sections on the applications of Acr proteins for eukaryotic and in vitro systems and regulation of Acr proteins, and the informational boxes on the advantages and limitations of Acr proteins. R.P.R. wrote the introduction, informational box for Acr protein discovery, and Table 1. B.C. wrote the sections on controlling gene drives with Acr proteins and applications of Acr proteins for prokaryotic systems. J.B.-D. supervised and wrote the manuscript with N.D.M, R.P.R. and B.C. All authors contributed to figure content and edited the manuscript.

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Correspondence to Joseph Bondy-Denomy.

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J.B.-D. is a scientific advisory board member of SNIPR Biome and Excision Biotherapeutics and a scientific advisory board member and co-founder of Acrigen Biosciences. J.B.-D. and N.D.M. have filed patents on technology related to anti-CRISPR proteins. R.P.R. is a consultant for Ancilia Inc.

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Marino, N.D., Pinilla-Redondo, R., Csörgő, B. et al. Anti-CRISPR protein applications: natural brakes for CRISPR-Cas technologies. Nat Methods 17, 471–479 (2020).

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