articleScienceAug 14, 2008GREEN OA

Small CRISPR RNAs Guide Antiviral Defense in Prokaryotes

National Center for Biotechnology Information · University of Sheffield · +1 more institution

PubMed
Indexed incrossrefpubmed

Abstract

Prokaryotes acquire virus resistance by integrating short fragments of viral nucleic acid into clusters of regularly interspaced short palindromic repeats (CRISPRs). Here we show how virus-derived sequences contained in CRISPRs are used by CRISPR-associated (Cas) proteins from the host to mediate an antiviral response that counteracts infection. After transcription of the CRISPR, a complex of Cas proteins termed Cascade cleaves a CRISPR RNA precursor in each repeat and retains the cleavage products containing the virus-derived sequence. Assisted by the helicase Cas3, these mature CRISPR RNAs then serve as small guide RNAs that enable Cascade to interfere with virus proliferation. Our results demonstrate that…

No related works found for this paper.

Funding