Liver X and farnesoid X receptors (LXR and FXR, nomenclature as agreed by the NC-IUPHAR Subcommittee on Nuclear Hormone Receptors [78, 3]) are members of a steroid analogue-activated nuclear receptor subfamily, which form heterodimers with members of the retinoid X receptor family. Endogenous ligands for LXRs include hydroxycholesterols (OHC), while FXRs appear to be activated by bile acids. In humans and primates, NR1H5P is a pseudogene. However, in other mammals, it encodes a functional nuclear hormone receptor that appears to be involved in cholesterol biosynthesis [83]
