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, ROR{alpha} by both SUMO-1 and SUMO-2. SUMOylation of ROR{alpha} occurred on the 240th lysine residue at the hinge region of human protein. PIAS family members, PIASx{alpha}, PIAS3, and PIASy, increased SUMOylation of ROR{alpha}, whereas SENP2 specifically removed SUMO from ROR{alpha}. SUMOylation-defective mutant form of ROR{alpha} exhibited decreased transcriptional activity on ROR{alpha}-responsive promoters indicating that SUMOylation may positively regulate transcriptional function of ROR{alpha}.