Anti-CRISPR AcrIIA5 Potently Inhibits All Cas9 Homologs Used for Genome Editing
Bianca Garcia,
Jooyoung Lee,
Alireza Edraki,
Yurima Hidalgo-Reyes,
Steven Erwood,
Aamir Mir,
Chantel N. Trost,
Uri Seroussi,
Sabrina Y. Stanley,
Ronald D. Cohn,
Julie M. Claycomb,
Erik J. Sontheimer,
Karen L. Maxwell,
Alan R. Davidson
Affiliations
Bianca Garcia
Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
Jooyoung Lee
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
Alireza Edraki
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
Yurima Hidalgo-Reyes
Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
Steven Erwood
Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada; Program in Genetics and Genome Biology, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada
Aamir Mir
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
Chantel N. Trost
Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
Uri Seroussi
Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
Sabrina Y. Stanley
Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
Ronald D. Cohn
Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada; Program in Genetics and Genome Biology, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada; Department of Pediatrics, University of Toronto and The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
Julie M. Claycomb
Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
Erik J. Sontheimer
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA; Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
Karen L. Maxwell
Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada; Corresponding author
Alan R. Davidson
Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada; Corresponding author
Summary: CRISPR-Cas9 systems provide powerful tools for genome editing. However, optimal employment of this technology will require control of Cas9 activity so that the timing, tissue specificity, and accuracy of editing may be precisely modulated. Anti-CRISPR proteins, which are small, naturally occurring inhibitors of CRISPR-Cas systems, are well suited for this purpose. A number of anti-CRISPR proteins have been shown to potently inhibit subgroups of CRISPR-Cas9 systems, but their maximal inhibitory activity is generally restricted to specific Cas9 homologs. Since Cas9 homologs vary in important properties, differing Cas9s may be optimal for particular genome-editing applications. To facilitate the practical exploitation of multiple Cas9 homologs, here we identify one anti-CRISPR, called AcrIIA5, that potently inhibits nine diverse type II-A and type II-C Cas9 homologs, including those currently used for genome editing. We show that the activity of AcrIIA5 results in partial in vivo cleavage of a single-guide RNA (sgRNA), suggesting that its mechanism involves RNA interaction. : Garcia et al. show that anti-CRISPR protein AcrIIA5 strongly inhibits all of the CRISPR-Cas9 homologs that are commonly used for genome editing. They show that it functions effectively in bacterial and mammalian cells. This anti-CRISPR will be useful for a wide variety of biotechnological applications. Keywords: Cas9, anti-CRISPR, genome editing, bacteriophage
