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Anti-CRISPR: discovery, mechanism and function

Nature Reviews Microbiology volume 16, pages 12–17 (2018)Cite this article

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Abstract

CRISPR–Cas adaptive immune systems are widespread among bacteria and archaea. Recent studies have shown that these systems have minimal long-term evolutionary effects in limiting horizontal gene transfer. This suggests that the ability to evade CRISPR–Cas immunity must also be widespread in phages and other mobile genetic elements. In this Progress article, we discuss recent discoveries that highlight how phages inactivate CRISPR–Cas systems by using anti-CRISPR proteins, and we outline evolutionary and biotechnological implications of their activity.

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Figure 1: Anti-CRISPR gene discovery.
Figure 2: Inhibition of CRISPR–Cas systems by anti-CRISPR proteins is a common strategy across CRISPR–Cas system types and bacterial phylogeny.

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Acknowledgements

A.P. was supported by a Canadian Institutes of Health Research Doctoral Award. Research in this area in the authors' laboratories is supported by Canadian Institutes of Health Research grants to A.R.D. (MOP-130482) and K.L.M. (MOP-136845).

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Authors and Affiliations

  1. Department of Biochemistry, University of Toronto, Toronto, M5G 1M1, Ontario, Canada

    April Pawluk & Karen L. Maxwell

  2. Departments of Biochemistry and Molecular Genetics, University of Toronto, Toronto, M5G 1M1, Ontario, Canada

    Alan R. Davidson

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  1. April Pawluk
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Contributions

A.P. researched the data for the article. A.P. and K.L.M. wrote the article. A.P., K.L.M. and A.R.D. substantially contributed to discussions of the content and reviewed and edited the manuscript before submission.

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Correspondence to Karen L. Maxwell.

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Competing interests

The authors declare potential competing interest as all authors have a patent pending for anti-CRISPR technologies on which they are inventors.

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Pawluk, A., Davidson, A. & Maxwell, K. Anti-CRISPR: discovery, mechanism and function. Nat Rev Microbiol 16, 12–17 (2018). https://doi.org/10.1038/nrmicro.2017.120

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