Cited by 1,423CRISPR and Genetic EngineeringBacterial Genetics and BiotechnologyRNA regulation and disease

Diversity, classification and evolution of CRISPR-Cas systems

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Koonin, Eugene V, Makarova, Kira S, Zhang, Feng·2017·Current Opinion in Microbiology

Abstract

The bacterial and archaeal CRISPR-Cas systems of adaptive immunity show remarkable diversity of protein composition, effector complex structure, genome locus architecture and mechanisms of adaptation, pre-CRISPR (cr)RNA processing and interference. The CRISPR-Cas systems belong to two classes, with multi-subunit effector complexes in Class 1 and single-protein effector modules in Class 2. Concerted genomic and experimental efforts on comprehensive characterization of Class 2 CRISPR-Cas systems led to the identification of two new types and several subtypes. The newly characterized type VI systems are the first among the CRISPR-Cas variants to exclusively target RNA. Unexpectedly, in some of the class 2 systems, the effector protein is additionally responsible for the pre-crRNA processing. Comparative analysis of the effector complexes indicates that Class 2 systems evolved from mobile genetic elements on multiple, independent occasions.

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  • Organisms possessing CRISPR-Cas systems can identify and degrade foreign DNA.

    “Therefore, organisms possessing CRISPR-Cas systems can identify and degrade foreign DNA.”

    From Characterization of Limnospira platensis PCC 9108 R-M and CRISPR-Cas systems (2024) · cites this paper as Koonin et al., 2017

  • CRISPR-Cas is an adaptive immunity system that confers immune memory stored in the form of spacer sequences derived from foreign DNA inserted into the leader-repeat junction.

    “CRISPR-Cas (that stand for Clustered Regularly Interspaced Short Palindromic Repeats and CRISPR-associated proteins) is an adaptive immunity system that confers immune memory stored in the form of spacer sequences derived from foreign DNA inserted into the leaderrepeat junction (Garrett et al., 2011; Koonin et al., 2017).”

    From Characterization of Limnospira platensis PCC 9108 R-M and CRISPR-Cas systems (2024) · cites this paper as Koonin et al., 2017

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Authors
Koonin, E. V., Makarova, K. S., & Zhang, F.
Affiliations
  • United States National Library of Medicine (US)
  • Broad Institute (US)
Corresponding author
Koonin, Eugene V
Venue
Current Opinion in Microbiology
Publisher
Elsevier BV
Published
2017-06
Volume
37
Pages
67-78
ISSN
1369-5274 (ISSN-L)
OpenAlex
W2623277795
Cited by
1,423
References
73
Citations by year
2026: 70 · 2025: 139 · 2024: 157 · 2023: 136 · 2022: 184 · 2021: 191 · 2020: 178 · 2019: 206 · 2018: 127 · 2017: 33 · 2013: 1
FWCI
13.98
Type
journal article
Language
en
Open access
Locations
  • Current Opinion in Microbiology (publishedVersion)
  • PubMed (publishedVersion)
  • Europe PMC (PubMed Central) (acceptedVersion)
  • PubMed Central (acceptedVersion)
  • DSpace@MIT (Massachusetts Institute of Technology) (submittedVersion, cc-by-nc-nd)
Funders
  • National Institutes of Health
  • U.S. National Library of Medicine (Z01LM000073)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › CRISPR and Genetic Engineering
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Bacterial Genetics and Biotechnology
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › RNA regulation and disease
Keywords
CRISPR-Cas, adaptive immunity, mobile genetic elements, CRISPR adaptation, comparative genomics
MeSH terms
Archaea, Bacteria, Genetic Variation, Evolution, Molecular, CRISPR-Cas Systems

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