CRISPR (clustered regularly interspaced short palindromic repeats)–Cas (CRISPR-associated) is an adaptive immunity system in bacteria and archaea that functions via a distinct self/non-self recognition mechanism that involves unique spacers homologous with viral or plasmid DNA and integrated into the CRISPR loci. Most of the Cas proteins evolve under relaxed purifying selection and some underwent dramatic structural rearrangements during evolution. In many cases, CRISPR–Cas system components are replaced either by homologous or by analogous proteins or domains in some bacterial and archaeal lineages. However, recent advances in comparative sequence analysis, structural studies and experimental data suggest that, despite this remarkable evolutionary plasticity, all CRISPR–Cas systems employ the same architectural and functional principles, and given the conservation of the principal building blocks, share a common ancestry. We review recent advances in the understanding of the evolution and organization of CRISPR–Cas systems. Among other developments, we describe for the first time a group of archaeal cas1 gene homologues that are not associated with CRISPR–Cas loci and are predicted to be involved in functions other than adaptive immunity.
Skip Nav Destination
Article navigation
December 2013
-
Cover Image
Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
Conference Article|
November 20 2013
The basic building blocks and evolution of CRISPR–Cas systems
Kira S. Makarova;
Kira S. Makarova
1
*National Center for Biotechnology Information, NLM, National Institutes of Health, Bethesda, MD 20894, U.S.A.
1To whom correspondence should be addressed (emailmakarova@ncbi.nlm.nih.gov).
Search for other works by this author on:
Yuri I. Wolf;
Yuri I. Wolf
*National Center for Biotechnology Information, NLM, National Institutes of Health, Bethesda, MD 20894, U.S.A.
Search for other works by this author on:
Eugene V. Koonin
Eugene V. Koonin
*National Center for Biotechnology Information, NLM, National Institutes of Health, Bethesda, MD 20894, U.S.A.
Search for other works by this author on:
Publisher: Portland Press Ltd
Received:
March 27 2013
Online ISSN: 1470-8752
Print ISSN: 0300-5127
© The Authors Journal compilation © 2013 Biochemical Society
2013
Biochem Soc Trans (2013) 41 (6): 1392–1400.
Article history
Received:
March 27 2013
Citation
Kira S. Makarova, Yuri I. Wolf, Eugene V. Koonin; The basic building blocks and evolution of CRISPR–Cas systems. Biochem Soc Trans 1 December 2013; 41 (6): 1392–1400. doi: https://doi.org/10.1042/BST20130038
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Captcha Validation Error. Please try again.