SUMOylation of RORα potentiates transcriptional activation function

SUMOylation regulates a variety of cellular processes, including control of transcriptional activities of nuclear receptors. Here, we present SUMOylation of orphan nuclear receptor, RORα by both SUMO-1 and SUMO-2. SUMOylation of RORα occurred on the 240th lysine residue at the hinge region of human protein. PIAS family members, PIASxα, PIAS3, and PIASy, increased SUMOylation of RORα, whereas SENP2 specifically removed SUMO from RORα. SUMOylation-defective mutant form of RORα exhibited decreased transcriptional activity on RORα-responsive promoters indicating that SUMOylation may positively regulate transcriptional function of RORα.