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CRISPR-Cas: an adaptive immunity system in prokaryotes.

ABSTRACT: Most of the archaea and numerous bacteria possess an elaborate system of adaptive immunity to mobile genetic elements known as the CRISPR (clustered regularly interspaced short palindromic repeats)-associated system (CRISPR-Cas), which consists of arrays of short repeats interspersed with unique DNA spacers and adjacent operons encompassing CRISPR-associated (cas) genes with predicted and, in some cases, experimentally validated nuclease, helicase, and polymerase activities. The system functions by integrating fragments of alien DNA between the repeats and employing their transcripts to degrade the DNA of the respective invading elements via an RNA interference-like mechanism. The CRISPR-Cas system is a case of apparent Lamarckian inheritance.

SUBMITTER: Koonin EV

PROVIDER: S-EPMC2884157 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

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CRISPR-Cas: an adaptive immunity system in prokaryotes.

Koonin Eugene V EV Makarova Kira S KS

F1000 biology reports 20091201

Most of the archaea and numerous bacteria possess an elaborate system of adaptive immunity to mobile genetic elements known as the CRISPR (clustered regularly interspaced short palindromic repeats)-associated system (CRISPR-Cas), which consists of arrays of short repeats interspersed with unique DNA spacers and adjacent operons encompassing CRISPR-associated (cas) genes with predicted and, in some cases, experimentally validated nuclease, helicase, and polymerase activities. The system functions ...[more]

PMID: 20556198

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