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CRISPR-Associated Protein 9 MeSH Descriptor Data 2025


MeSH Heading
CRISPR-Associated Protein 9
Tree Number(s)
D08.811.277.352.355.325.150
D12.776.097.219
D12.776.212.500
Unique ID
D000076987
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D000076987
Scope Note
An RNA-guided endodeoxyribonuclease that associates with CRISPR SEQUENCES in STREPTOCOCCUS PYOGENES and other bacteria where it participates in an adaptive immune function to cleave foreign DNA complimentary to small GUIDE RNA (sgRNAs). Structurally, Cas9 consists of an ALPHA-HELIX module and a nuclease module connected by a single helix. The nuclease module contains two enzymatic domains: RuvC, which cleaves non-target DNA strand, and an HNH nuclease domain, which cleaves the target strand. Specificity for the DNA target depends on the presence of a protospacer adjacent motif (PAM) sequence, a 2-6 nucleotide DNA sequence immediately following the sequence targeted by Cas9.
Entry Term(s)
Cas9 Endonuclease
Cas9 Enzyme
Cas9 Protein
Registry Numbers
EC 3.1.-
Previous Indexing
Bacterial Proteins (2015-2018)
Endonucleases (2015-2018)
See Also
CRISPR-Cas Systems
Gene Editing
Public MeSH Note
2019
History Note
2019
Date Established
2019/01/01
Date of Entry
2018/07/09
Revision Date
2021/07/07
CRISPR-Associated Protein 9 Preferred
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