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RNA Polymerase I MeSH Descriptor Data 2026


MeSH Heading
RNA Polymerase I
Tree Number(s)
D08.811.913.696.445.735.270.750
Unique ID
D012318
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D012318
Scope Note
A DNA-dependent RNA polymerase present in bacterial, plant, and animal cells. The enzyme functions in the nucleolar structure and transcribes DNA into RNA. It has different requirements for cations and salts than RNA polymerase II and III and is not inhibited by alpha-amanitin.
Entry Term(s)
DNA-Dependent RNA Polymerase I
RNA Polymerase A
Registry Numbers
EC 2.7.7.6
Previous Indexing
RNA Nucleotidyltransferases (1968-1972)
RNA Polymerases (1973-1976)
Public MeSH Note
84; was see under RNA POLYMERASES 1977-83
History Note
84(77); was see under RNA POLYMERASES 1977-83
Date Introduced
1984/01/01
Last Updated
2016/06/29
RNA Polymerase I Preferred
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