Farnesoid X Receptor (FXR)

The farnesoid X receptor (FXR),is a nuclear hormone receptor with activity similar to that seen in other steroid receptors such as estrogen or progesterone but more similar in form to PPAR, LXR and RXR. FXR is encoded by the NR1H4 gene.

FXR is expressed at high levels in the liver and intestine. Chenodeoxycholic acid and other bile acids are natural ligands for FXR. Like other steroid receptors, when activated, FXR translocates to the cell nucleus, forms a dimer (in this case a heterodimer with RXR) and binds to hormone response elements on DNA which elicits expression or transrepression of gene products.