FXR binds to the LRH-1 responsive element in the hSHP promoter.

FXR was precipitated from nuclear extracts of hFXR-overexpressing DLD-1 cells using a DNA probe containing the SHP −122/−69 region (“wild type”(WT) or “mutated”(mut)), the IR-1 from the hBSEP promoter (positive control), the LacI binding site (negative control) or empty beads (EB, negative control). A) DNA probes of SHP −122/−69 and BSEP-IR-1 bind FXR. Competition experiments were performed with 3-fold excess hBSEP-IR-1 or LacI lacking a biotin label. B) the SHP −122/−69 region with a mutated LRH-1 site failed to precipitate or compete for FXR binding. Competition experiments were performed with 3-fold excess wild type SHP −122/−69, mutated SHP −122/−69 or LacI lacking a biotin label.