The ring of confidence: a haloarchaeal CRISPR/Cas system.

@article{Maier2013TheRO,
  title={The ring of confidence: a haloarchaeal CRISPR/Cas system.},
  author={Lisa-Katharina Maier and Britta Stoll and Jutta Brendel and Susan Fischer and Friedhelm Pfeiffer and Michael Dyall-Smith and Anita Marchfelder},
  journal={Biochemical Society transactions},
  year={2013},
  volume={41 1},
  pages={
          374-8
        }
}
To survive the constant invasions by foreign genetic elements, prokaryotes have evolved various defensive systems. Almost all sequenced archaea, and half of the analysed bacteria use the CRISPR (clustered regularly interspaced short palindromic repeats)/Cas (CRISPR-associated) system, a recently identified prokaryotic immune system that can fend off invading elements in a sequence-specific manner. Few archaeal CRISPR/Cas systems have been analysed so far, and the molecular details of many of… 
View on PubMed
biochemsoctrans.org
17 Citations
Background Citations
4
Methods Citations
1

Figures from this paper

17 Citations

Citation Type

Citation Type

The Adaptive Immune System of Haloferax volcanii
TLDR
The characteristics of the CRISPR-Cas system of Haloferax volcanii, an extremely halophilic archaeon originally isolated from the Dead Sea, are summarized, revealing that six protospacer adjacent motif (PAM) sequences are recognised by theHaloferax defence system.
CRISPR and Salty: CRISPR-Cas Systems in Haloarchaea
TLDR
Haloarchaea is one of few archaeal classes in which CRISPR-Cas systems have been investigated in more than one genus and the available information on CRISpr-Cas defence in three Haloarchaea are summarized.
Investigation of prokaryotic immune defense system with quantitative and structural mass spectrometry
TLDR
The UV induced protein-RNA cross-liking approach was utilized to investigate RNA binding regions in single (recombinant) Cas proteins such as the archaeal and bacterial Cas6b proteins and the Cas7 family proteins from four different organisms, and these structural studies were extended to multi-subunit crRNP complexes.
Requirements for a successful defence reaction by the CRISPR-Cas subtype I-B system.
TLDR
The prerequisites for the detection and degradation of invaders in the halophilic archaeon Haloferax volcanii are summarized and results indicate a dependency on the type of origin present on the plasmid.
Gene Repression in Haloarchaea Using the CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)-Cas I-B System*
TLDR
This work uses the model archaeon Haloferax volcanii to demonstrate that its endogenous CRISPR-Cas system I-B can be harnessed to repress gene expression in archaea and results in efficient repression of transcription.
CRISPRi for Archaea
TLDR
Here the model archaeon Haloferax volcanii is used to demonstrate that its endogenous CRISPR-Cas system I-B can be harnessed to repress gene expression in archaea.
CRISPRi as an efficient tool for gene repression in archaea.
Prokaryotic immune defence with an icrRNA and without Cas 6 1 An Active Immune Defence with a Minimal CRISPR ( clustered regularly interspaced short palindromic repeats ) RNA and Without the Cas 6 Protein
TLDR
A Cas6b-independent crRNA maturation pathway for the Haloferax type I-B system in vivo, that expresses a functional crRNA that is termed independently generated crRNA (icrRNA) that is effective in triggering degradation of an invader plasmid carrying the matching protospacer sequence.
A Complex of Cas Proteins 5, 6, and 7 Is Required for the Biogenesis and Stability of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-derived RNAs (crRNAs) in Haloferax volcanii*
TLDR
It is shown that additional Cas proteins that form a CRISPR-associated complex for antiviral defense (Cascade)-like complex are needed for crRNA stability in the CRISpr-Cas type I-B system in Haloferax volcanii in vivo, the first systematic in vivo analysis of Cas6 protein variants.
New Insights Into Functions and Possible Applications of Clostridium difficile CRISPR-Cas System
TLDR
The recent advances in characterization of original features of the C. difficile CRISPR-Cas system in laboratory and clinical strains are discussed, as well as interesting perspectives for the understanding of this defense system function and regulation in this important enteropathogen.
...
1
2
...

References

SHOWING 1-10 OF 18 REFERENCES
In vivo activity of CRISPR‐mediated virus defence in a hyperthermophilic archaeon
TLDR
In vivo activity of CRISPR/Cas in archaea for the first time is demonstrated and it is suggested that – unlike the recently demonstrated in vitro cleavage of RNA in Pyrococcus– DNA is targeted in this archaeon.
An Archaeal Immune System Can Detect Multiple Protospacer Adjacent Motifs (PAMs) to Target Invader DNA*
TLDR
The CRISPR/Cas system in Haloferax recognized six different PAM sequences that could trigger a defense response, indicating that the PAM sequence specificity of the defense response in type ICRISPR systems is more relaxed than previously thought.
CRISPR-Cas systems in bacteria and archaea: versatile small RNAs for adaptive defense and regulation.
TLDR
Exciting breakthroughs in understanding the mechanisms of the CRISPR-Cas system and its potential for biotechnological applications and understanding evolutionary dynamics are discussed.
Evolution and classification of the CRISPR–Cas systems
TLDR
An updated analysis of the evolutionary relationships between CRISPR–Cas systems and Cas proteins is provided and a 'polythetic' classification that integrates the phylogenies of the most common cas genes, the sequence and organization of theCRISPR repeats and the architecture of the CRISpr–cas loci is proposed.
Short motif sequences determine the targets of the prokaryotic CRISPR defence system.
TLDR
It is shown that the conservation of proto-spacer adjacent motifs (PAMs) is a common theme for the most diverse CRISPR systems, implying that there is aCRISPR-type-specific (motif-directed) choice of the spacers, which subsequently determines the interference target.
Archaeal CRISPR-based immune systems: exchangeable functional modules.
Clustered regularly interspaced short palindromic repeats (CRISPRs): the hallmark of an ingenious antiviral defense mechanism in prokaryotes
TLDR
An application of the CRISPR/Cas system is the immunization of industry-relevant prokaryotes (or eukaryotes) against mobile-genetic invasion, and the high variability of theCRISPR spacer content can be exploited for phylogenetic and evolutionary studies.
Identification and characterization of E. coli CRISPR‐cas promoters and their silencing by H‐NS
TLDR
It is demonstrated that the DNA‐binding protein H‐NS is involved in silencing the CRISPR‐cas promoters, resulting in cryptic Cas protein expression, and suggested a potential link between two prokaryotic defence systems against foreign DNA.
A putative RNA-interference-based immune system in prokaryotes: computational analysis of the predicted enzymatic machinery, functional analogies with eukaryotic RNAi, and hypothetical mechanisms of action
TLDR
It appears most likely that CASS is a prokaryotic system of defense against phages and plasmids that functions via the RNAi mechanism, which seems to involve integration of fragments of foreign genes into archaeal and bacterial chromosomes yielding heritable immunity to the respective agents.
The CRISPR/Cas bacterial immune system cleaves bacteriophage and plasmid DNA
TLDR
In vivo evidence is provided that the Streptococcus thermophilus CRISPR1/Cas system can also naturally acquire spacers from a self-replicating plasmid containing an antibiotic-resistance gene, leading toplasmid loss.
...
1
2
...