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CRISPR-CasΦ from huge phages is a hypercompact genome editor.

ABSTRACT: CRISPR-Cas systems are found widely in prokaryotes, where they provide adaptive immunity against virus infection and plasmid transformation. We describe a minimal functional CRISPR-Cas system, comprising a single ~70-kilodalton protein, CasΦ, and a CRISPR array, encoded exclusively in the genomes of huge bacteriophages. CasΦ uses a single active site for both CRISPR RNA (crRNA) processing and crRNA-guided DNA cutting to target foreign nucleic acids. This hypercompact system is active in vitro and in human and plant cells with expanded target recognition capabilities relative to other CRISPR-Cas proteins. Useful for genome editing and DNA detection but with a molecular weight half that of Cas9 and Cas12a genome-editing enzymes, CasΦ offers advantages for cellular delivery that expand the genome editing toolbox.

SUBMITTER: Pausch P

PROVIDER: S-EPMC8207990 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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CRISPR-CasΦ from huge phages is a hypercompact genome editor.

Pausch Patrick P Al-Shayeb Basem B Bisom-Rapp Ezra E Tsuchida Connor A CA Li Zheng Z Cress Brady F BF Knott Gavin J GJ Jacobsen Steven E SE Banfield Jillian F JF Doudna Jennifer A JA

Science (New York, N.Y.) 20200701 6501

CRISPR-Cas systems are found widely in prokaryotes, where they provide adaptive immunity against virus infection and plasmid transformation. We describe a minimal functional CRISPR-Cas system, comprising a single ~70-kilodalton protein, CasΦ, and a CRISPR array, encoded exclusively in the genomes of huge bacteriophages. CasΦ uses a single active site for both CRISPR RNA (crRNA) processing and crRNA-guided DNA cutting to target foreign nucleic acids. This hypercompact system is active in vitro an ...[more]

PMID: 32675376

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