Nuclear receptor that acts as a key metabolic sensor by regulating the expression of genes involved in bile acid synthesis, cholesterol homeostasis and triglyceride synthesis. Together with the oxysterol receptors NR1H3/LXR-alpha and NR1H2/LXR-beta, acts as an essential transcriptional regulator of lipid metabolism. Plays an anti-inflammatory role during the hepatic acute phase response by acting as a corepressor: inhibits the hepatic acute phase response by preventing dissociation of the N-Cor corepressor complex. Key regulator of cholesterol 7-alpha-hydroxylase gene (CYP7A) expression in liver. May also contribute to the regulation of pancreas-specific genes and play important roles in embryonic development (By similarity). Activates the transcription of CYP2C38 (PubMed:30555544). Binds DNA as a monomer (By similarity). Interacts with GRIP1, NCOA2 and NR0B2 (PubMed:12820970, PubMed:15976031). Interacts (when sumoylated) with GPS2; interaction with GPS2 onto hepatic acute phase protein promoters prevents N-Cor corepressor complex dissociation (By similarity). Sumoylated by SUMO1 at Lys-289 during the hepatic acute phase response, leading to promote interaction with GPS2 and prevent N-Cor corepressor complex dissociation. Belongs to the nuclear hormone receptor family. NR5 subfamily.