UDP Glucuronosyltransferase 2 Family, Polypeptide B1 (UGT2B1)

UGT2B1 is expressed mainly in the liver where it glucuronidates steroids and environmental toxins and carcinogens. A region between -42 and -55 bp upstream from the UGT2B1 gene transcription start site was previously identified as sharing sequence similarity with the hepatocyte nuclear factor 1 (HNF1) consensus binding site. A minimal UGT2B1 gene promoter containing the putative HNF1 binding site was fused to the CAT reporter gene and transfected into HepG2 cells. Only low levels of CAT activity were detected. This activity was increased 50-fold when an HNF1 alpha expression vector was co-transfected with the UGT2B1 promoter CAT construct but was not altered when a HNF1 beta expression vector was used. A UGT2B1 promoter construct with the HNF1-like region deleted was not activated by either co-transfected HNF1 expression vector.