Accepted name: [histone H3]-trimethyl-L-lysine9 demethylase
Reaction: a [histone H3]-N6,N6,N6-trimethyl-L-lysine9 + 2 2-oxoglutarate + 2 O2 = a [histone H3]-N6-methyl-L-lysine9 + 2 succinate + 2 formaldehyde + 2 CO2 (overall reaction)
(1a) a [histone H3]-N6,N6,N6-trimethyl-L-lysine9 + 2-oxoglutarate + O2 = a [histone H3]-N6,N6-dimethyl-L-lysine9 + succinate + formaldehyde + CO2
(1b) a [histone H3]-N6,N6-dimethyl-L-lysine9 + 2-oxoglutarate + O2 = a [histone H3]-N6-methyl-L-lysine9 + succinate + formaldehyde + CO2
Other name(s): KDM4A (gene name); KDM4B (gene name); KDM4C (gene name); KDM4D (gene name); JHDM3A (gene name); JMJD2 (gene name); JMJD2A (gene name); GASC1 (gene name)
Systematic name: [histone H3]-N6,N6,N6-trimethyl-L-lysine9,2-oxoglutarate:oxygen oxidoreductase
Comments: Requires iron(II). This entry describes a group of enzymes that demethylate N-methylated Lys-9 residues in the tail of the histone protein H3 (H3K9). This lysine residue can exist in three methylation states (mono-, di- and trimethylated), but this group of enzymes only act on the the tri- and di-methylated forms. The enzymes are dioxygenases and act by hydroxylating the methyl group, forming an unstable hemiaminal that leaves as formaldehyde. cf. EC, [histone H3]-dimethyl-L-lysine9 demethylase.
1.  Cloos, P.A., Christensen, J., Agger, K., Maiolica, A., Rappsilber, J., Antal, T., Hansen, K.H. and Helin, K. The putative oncogene GASC1 demethylates tri- and dimethylated lysine 9 on histone H3. Nature 442 (2006) 307–311. [PMID: 16732293]
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3.  Klose, R.J., Yamane, K., Bae, Y., Zhang, D., Erdjument-Bromage, H., Tempst, P., Wong, J. and Zhang, Y. The transcriptional repressor JHDM3A demethylates trimethyl histone H3 lysine 9 and lysine 36. Nature 442 (2006) 312–316. [PMID: 16732292]
4.  Whetstine, J.R., Nottke, A., Lan, F., Huarte, M., Smolikov, S., Chen, Z., Spooner, E., Li, E., Zhang, G., Colaiacovo, M. and Shi, Y. Reversal of histone lysine trimethylation by the JMJD2 family of histone demethylases. Cell 125 (2006) 467–481. [PMID: 16603238]
[EC created 2019]