Abstract

Retinoic acid receptor-related orphan receptors (RORs) regulate a variety of physiological processes including hepatic gluconeogenesis, lipid metabolism, circadian rhythm, and immune function. Here we present the first high-affinity synthetic ligand for both RORα and RORγ. In a screen against all 48 human nuclear receptors, the benzenesulfonamide liver X receptor (LXR) agonist N-(2,2,2-trifluoroethyl)-N-[4-[2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl]phenyl]-benzenesulfonamide (T0901317) inhibited transactivation activity of RORα and RORγ but not RORβ. T0901317 was found to directly bind to RORα and RORγ with high affinity (K_i = 132 and 51 nM, respectively), resulting in the modulation of the receptor's ability to interact with transcriptional cofactor proteins. T0901317 repressed RORα/γ-dependent transactivation of ROR-responsive reporter genes and in HepG2 cells reduced recruitment of steroid receptor coactivator-2 by RORα at an endogenous ROR target gene (G6Pase). Using small interference RNA, we demonstrate that repression of the gluconeogenic enzyme glucose-6-phosphatase in HepG2 cells by T0901317 is ROR-dependent and is not due to the compound's LXR activity. In summary, T0901317 represents a novel chemical probe to examine RORα/γ function and an excellent starting point for the development of ROR selective modulators. More importantly, our results demonstrate that small molecules can be used to target the RORs for therapeutic intervention in metabolic and immune disorders.