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Systematic discovery of natural CRISPR-Cas12a inhibitors.

ABSTRACT: Cas12a (Cpf1) is a CRISPR-associated nuclease with broad utility for synthetic genome engineering, agricultural genomics, and biomedical applications. Although bacteria harboring CRISPR-Cas9 or CRISPR-Cas3 adaptive immune systems sometimes acquire mobile genetic elements encoding anti-CRISPR proteins that inhibit Cas9, Cas3, or the DNA-binding Cascade complex, no such inhibitors have been found for CRISPR-Cas12a. Here we use a comprehensive bioinformatic and experimental screening approach to identify three different inhibitors that block or diminish CRISPR-Cas12a-mediated genome editing in human cells. We also find a widespread connection between CRISPR self-targeting and inhibitor prevalence in prokaryotic genomes, suggesting a straightforward path to the discovery of many more anti-CRISPRs from the microbial world.

SUBMITTER: Watters KE

PROVIDER: S-EPMC6185749 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Systematic discovery of natural CRISPR-Cas12a inhibitors.

Watters Kyle E KE Fellmann Christof C Bai Hua B HB Ren Shawn M SM Doudna Jennifer A JA

Science (New York, N.Y.) 20180906 6411

Cas12a (Cpf1) is a CRISPR-associated nuclease with broad utility for synthetic genome engineering, agricultural genomics, and biomedical applications. Although bacteria harboring CRISPR-Cas9 or CRISPR-Cas3 adaptive immune systems sometimes acquire mobile genetic elements encoding anti-CRISPR proteins that inhibit Cas9, Cas3, or the DNA-binding Cascade complex, no such inhibitors have been found for CRISPR-Cas12a. Here we use a comprehensive bioinformatic and experimental screening approach to id ...[more]

PMID: 30190307

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