RNA in defense: CRISPRs protect prokaryotes against mobile genetic elements.

@article{Jore2012RNAID,
  title={RNA in defense: CRISPRs protect prokaryotes against mobile genetic elements.},
  author={M. M. Jore and Stan J. J. Brouns and J. van der Oost},
  journal={Cold Spring Harbor perspectives in biology},
  year={2012},
  volume={4 6}
}
The CRISPR/Cas system in prokaryotes provides resistance against invading viruses and plasmids. Three distinct stages in the mechanism can be recognized. Initially, fragments of invader DNA are integrated as new spacers into the repetitive CRISPR locus. Subsequently, the CRISPR is transcribed and the transcript is cleaved by a Cas protein within the repeats, generating short RNAs (crRNAs) that contain the spacer sequence. Finally, crRNAs guide the Cas protein machinery to a complementary… Expand
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