RAR-related orphan receptor gamma (RORγ (also sometimes RORC for the gene; for the thymus-specific isoform, RORγt))

RAR-related orphan receptor gamma (RORγ) is a nuclear receptor and transcription factor encoded by the RORC gene, with two main isoforms: RORγ1 (or RORC1), widely expressed, and RORγt (or RORC2), specifically expressed in developing thymocytes and certain immune cells. RORγt is a master regulator of Th17 cell differentiation, lymphoid organogenesis, and immune homeostasis, controlling the expression of interleukin-17 (IL-17) and related cytokines. Because of its central role in pro-inflammatory immune responses, RORγ—especially RORγt—is considered a major therapeutic target for autoimmune diseases and cancer immunotherapy. Both natural (oxysterols) and synthetic ligands have been identified, and drug modulation (agonism or inverse agonism) alters immune cell fate by shifting the balance of coactivator/corepressor recruitment and downstream gene transcription. Clinical development of RORγ modulators is ongoing, but significant safety and efficacy challenges remain, particularly related to immunosuppression and off-target effects.

Other names

nuclear receptor ROR-gammanuclear receptor RZR-gammaRORC1 (long isoform)RORγt (thymus-specific isoform, also known as RORC2)RORγ1RZRγThorthymus orphan receptorTOR

Agonism: Small molecules or endogenous oxysterols bind to the ligand-binding domain, stabilize the activation helix (H12), recruit coactivators, increase transcription of target genes (including those for Th17 differentiation and IL-17 production). Inverse agonism/antagonism: Small molecules induce a conformational shift that impairs coactivator binding, recruits corepressors, suppresses gene transcription (inhibiting Th17 cell development and inflammatory cytokine production).