IUBMB Enzyme Nomenclature


Accepted name: [histone H3]-lysine27 N-methyltransferase

Reaction: S-adenosyl-L-methionine + a [histone H3]-L-lysine27 = S-adenosyl-L-homocysteine + a [histone H3]-N6-methyl-L-lysine27

Other name(s): ATXR5 (gene name)

Systematic name: S-adenosyl-L-methionine:[histone H3]-L-lysine27 N6-methyltransferase

Comments: This entry describes enzymes that methylate the L-lysine-27 residue of histone H3 only once, generating a monomethylated form. This modification influences the binding of chromatin-associated proteins. The methylation of lysine-27 leads to transcriptional repression of the affected target genes. cf. EC, [histone H3]-lysine27 N-dimethyltransferase, and EC, [histone H3]-lysine27 N-trimethyltransferase.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc PDB, CAS registry number:


1. Jacob, Y., Feng, S., LeBlanc, C.A., Bernatavichute, Y.V., Stroud, H., Cokus, S., Johnson, L.M., Pellegrini, M., Jacobsen, S.E. and Michaels, S.D. ATXR5 and ATXR6 are H3K27 monomethyltransferases required for chromatin structure and gene silencing. Nat. Struct. Mol. Biol. 16 (2009) 763-768. [PMID: 19503079]

[EC created 2020.]

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