Uptake of foreign mobile genetic elements is often detrimental and can result in cell death. For protection against invasion, prokaryotes have developed several defence mechanisms, which take effect at all stages of infection; an example is the recently discovered CRISPR (clustered regularly interspaced short palindromic repeats)–Cas (CRISPR-associated) immune system. This defence system directly degrades invading genetic material and is present in almost all archaea and many bacteria. Current data indicate a large variety of mechanistic molecular approaches. Although almost all archaea carry this defence weapon, only a few archaeal systems have been fully characterized. In the present paper, we summarize the prerequisites for the detection and degradation of invaders in the halophilic archaeon Haloferax volcanii. H. volcanii encodes a subtype I-B CRISPR–Cas system and the defence can be triggered by a plasmid-based invader. Six different target-interference motifs are recognized by the Haloferax defence and a 9-nt non-contiguous seed sequence is essential. The repeat sequence has the potential to fold into a minimal stem–loop structure, which is conserved in haloarchaea and might be recognized by the Cas6 endoribonuclease during the processing of CRISPR loci into mature crRNA (CRISPR RNA). Individual crRNA species were present in very different concentrations according to an RNA-Seq analysis and many were unable to trigger a successful defence reaction. Recognition of the plasmid invader does not depend on its copy number, but instead results indicate a dependency on the type of origin present on the plasmid.
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
Requirements for a successful defence reaction by the CRISPR–Cas subtype I-B system
Britta Stoll;
Britta Stoll
*Biology II, Ulm University, Albert-Einstein-Allee 11, 89069 Ulm, Germany
Search for other works by this author on:
Lisa-Katharina Maier;
Lisa-Katharina Maier
*Biology II, Ulm University, Albert-Einstein-Allee 11, 89069 Ulm, Germany
Search for other works by this author on:
Sita J. Lange;
Sita J. Lange
†Bioinformatics Group, Department of Computer Science, University of Freiburg, Georges-Köhler-Allee 106, 79110 Freiburg, Germany
Search for other works by this author on:
Jutta Brendel;
Jutta Brendel
*Biology II, Ulm University, Albert-Einstein-Allee 11, 89069 Ulm, Germany
Search for other works by this author on:
Susan Fischer;
Susan Fischer
*Biology II, Ulm University, Albert-Einstein-Allee 11, 89069 Ulm, Germany
Search for other works by this author on:
Rolf Backofen;
Rolf Backofen
†Bioinformatics Group, Department of Computer Science, University of Freiburg, Georges-Köhler-Allee 106, 79110 Freiburg, Germany
‡Centre for Biological Systems Analysis (ZBSA), University of Freiburg, Habsburgerstrasse 49, 79104 Freiburg, Germany
§Centre for Biological Signalling Studies (BIOSS), Cluster of Excellence, University of Freiburg, Schänzlestrasse 18, 79104 Freiburg, Germany
∥Centre for Non-Coding RNA in Technology and Health, University of Copenhagen, Grønnegårdsvej 3, 1870 Frederiksberg C, Denmark
Search for other works by this author on:
Anita Marchfelder
Anita Marchfelder
1
*Biology II, Ulm University, Albert-Einstein-Allee 11, 89069 Ulm, Germany
1To whom correspondence should be addressed (emailanita.marchfelder@uni-ulm.de).
Search for other works by this author on:
Publisher: Portland Press Ltd
Received:
June 03 2013
Online ISSN: 1470-8752
Print ISSN: 0300-5127
© The Authors Journal compilation © 2013 Biochemical Society
2013
Biochem Soc Trans (2013) 41 (6): 1444–1448.
Article history
Received:
June 03 2013
Citation
Britta Stoll, Lisa-Katharina Maier, Sita J. Lange, Jutta Brendel, Susan Fischer, Rolf Backofen, Anita Marchfelder; Requirements for a successful defence reaction by the CRISPR–Cas subtype I-B system. Biochem Soc Trans 1 December 2013; 41 (6): 1444–1448. doi: https://doi.org/10.1042/BST20130098
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.