PIAS1 SUMOylates DDX5 at lysine-53 with SUMO2 (Jacobs et al. 2007, Hendriks et al. 2014, Impens et al. 2014). SUMOylation reduces the coactivation activity of DDX5 with p53 but enhances coactivation of the estrogen receptor. SUMOylation also increases stability of DDX5 and promotes interaction of DDX5 with HDAC1. DDX5 is a coactivator of p53 (TP53).
Verlaan-de Vries, M,