NR1I2

Nuclear receptor that acts as a transcription factor regulating genes involved in the metabolism and excretion of xenobiotics, drugs, and endogenous compounds. Activated by a broad range of endogenous steroids (e.g. pregnenolone, progesterone) and xenobiotics, including the antibiotic rifampicin and certain plant-derived metabolites. Upon ligand binding, translocates to the nucleus, forms a heterodimer with the retinoid X receptor/RXR, and binds to response elements in target promoters, leading to transcriptional activation. Target genes include cytochrome P450 enzymes such as CYP3A4 and ATP-binding cassette transporters including ABCB1/MDR1..

Function from UniProtKB (O75469), read 2026-09-23. CC BY 4.0.