All characterized lysine demethylases other than KDM1A belong to the jumonjiC domain (JmjC) containing family.The JmjC KDMs are members of the Cupin superfamily of mononuclear Fe (II) dependent oxygenases, which are characterized by the presence of a double-stranded beta-helix core fold. The JmjC KDMs require 2 oxoglutarate (2 OG) and molecular oxygen as co substrates, producing, along with formaldehyde, succinate and carbon dioxide. This hydroxylation based mechanism does not require a protonatable lysine e amine group and consequently JmjC containing demethylases are able to demethylate tri , di and monomethylated lysines.
KDM6A (UTX), KDM6B (JMJD3), KDM6C (UTY) and KDM7A (JHDM1D) catalyse the demethylation of di or tri-methylated lysine-28 of histone H3 (H3K27Me2/3) (Agger et al. 2007, Cho et al. 2007, De Santra et al. 2007, Hong et al. 2007, Lan et al. 2007, Lee et al. 2007, Horton et al. 2010, Huang et al. 2010, Walport et al. 2014).