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CRISPR–Cas systems: beyond adaptive immunity

Nature Reviews Microbiology volume 12, pages 317–326 (2014)Cite this article

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Abstract

The discovery of CRISPR–Cas (clustered, regularly interspaced short palindromic repeats–CRISPR-associated proteins) adaptive immune systems in prokaryotes has been one of the most exciting advances in microbiology in the past decade. Their role in host protection against mobile genetic elements is now well established, but there is mounting evidence that these systems modulate other processes, such as the genetic regulation of group behaviour and virulence, DNA repair and genome evolution. In this Progress article, we discuss recent studies that have provided insights into these unconventional CRISPR–Cas functions and consider their potential evolutionary implications. Understanding the role of CRISPR–Cas in these processes will improve our understanding of the evolution and maintenance of CRISPR–Cas systems in prokaryotic genomes.

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Figure 1: Regulation of fruiting body formation in Myxococcus xanthus.
Figure 2: Virulence regulation by Cas9–tracrRNA–scaRNA in Francisella novicida.

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Acknowledgements

E.R.W. received funding from the People Programme (Marie Curie Actions) of the European Union's Seventh Framework Programme (FP7/2007-2013) under Research Executive Agency (REA) grant agreement number 327606. A.B. is supported by a UK Royal Society Wolfson Research Merit Award. P.C.F. is supported by a Rutherford Discovery Fellowship from the Royal Society of New Zealand.

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  1. Biosciences, University of Exeter, Penryn, Cornwall TR10 9EZ, UK.,

    Edze R. Westra & Angus Buckling

  2. Department of Microbiology and Immunology, University of Otago, Dunedin, 9054, New Zealand

    Peter C. Fineran

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Supplementary information S1 (figure)

The partial complementarity between the scaRNA, tracrRNA and blp transcript is shown in detail, which is proposed to facilitate complex formation and subsequent degradation of the blp transcript. (PDF 206 kb)

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Westra, E., Buckling, A. & Fineran, P. CRISPR–Cas systems: beyond adaptive immunity. Nat Rev Microbiol 12, 317–326 (2014). https://doi.org/10.1038/nrmicro3241

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