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Primary processing of CRISPR RNA by the endonuclease Cas6 in Staphylococcus epidermidis.

ABSTRACT: In many bacteria and archaea, an adaptive immune system (CRISPR-Cas) provides immunity against foreign genetic elements. This system uses CRISPR RNAs (crRNAs) derived from the CRISPR array, along with CRISPR-associated (Cas) proteins, to target foreign nucleic acids. In most CRISPR systems, endonucleolytic processing of crRNA precursors (pre-crRNAs) is essential for the pathway. Here we study the Cas6 endonuclease responsible for crRNA processing in the Type III-A CRISPR-Cas system from Staphylococcus epidermidis RP62a, a model for Type III-A CRISPR-Cas systems, and define substrate requirements for SeCas6 activity. We find that SeCas6 is necessary and sufficient for full-length crRNA biogenesis in vitro, and that it relies on both sequence and stem-loop structure in the 3' half of the CRISPR repeat for recognition and processing.

SUBMITTER: Wakefield N

PROVIDER: S-EPMC4593764 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Primary processing of CRISPR RNA by the endonuclease Cas6 in Staphylococcus epidermidis.

Wakefield Noelle N Rajan Rakhi R Sontheimer Erik J EJ

FEBS letters 20150910 20 Pt B

In many bacteria and archaea, an adaptive immune system (CRISPR-Cas) provides immunity against foreign genetic elements. This system uses CRISPR RNAs (crRNAs) derived from the CRISPR array, along with CRISPR-associated (Cas) proteins, to target foreign nucleic acids. In most CRISPR systems, endonucleolytic processing of crRNA precursors (pre-crRNAs) is essential for the pathway. Here we study the Cas6 endonuclease responsible for crRNA processing in the Type III-A CRISPR-Cas system from Staphylo ...[more]

PMID: 26364721

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