Molecular cloning and characterization of the murine bile salt export pump.

Article Details

Citation

Green RM, Hoda F, Ward KL

Molecular cloning and characterization of the murine bile salt export pump.

Gene. 2000 Jan 4;241(1):117-23.

PubMed ID
10607905 [ View in PubMed
]
Abstract

Hepatic bile salt secretion and bile formation are essential functions of the mammalian liver, and the rate-limiting step of hepatocellular secretion of bile salts is canalicular secretion. Recently, the rat sister-of-p-glycoprotein/bile salt export pump (spgp/BSEP) was demonstrated to encode for the rat ATP-dependent canalicular bile salt export protein, and mutations of human BSEP were identified as the cause of PFIC 2. Since mouse models are vital for studies in hepatocellular transport and metabolism, cloning and characterization of the murine gene are essential. In this study, we have cloned a full-length, functional cDNA for the mBsep. The deduced amino acid sequence encodes for a 1321-amino-acid protein and is 94% similar to rat and 89% similar to human bsep. Western immunoblotting using an antibody directed against a carboxy-terminal peptide of mbsep protein reveals a 160kDa protein, which is highly enriched in mouse canalicular membranes. Transfection of mBSEP into Sf-9 insect cells or mammalian Balb-3T3 cells confers functional transport of the bile salt taurocholate. The mBsep mRNA is expressed in murine liver, but not in other tissues. Hepatic mBsep levels appear highly regulated, being markedly diminished in both LPS and estrogen models of cholestasis. These data are important for further murine studies of hepatocellular transport physiology and metabolism.

DrugBank Data that Cites this Article

Drug Transporters
DrugTransporterKindOrganismPharmacological ActionActions
Cholic AcidBile salt export pumpProteinHumans
Unknown
Substrate
Inhibitor
Inducer
Details
Taurocholic acidBile salt export pumpProteinHumans
Unknown
Substrate
Inducer
Details
Ursodeoxycholic acidBile salt export pumpProteinHumans
Unknown
Substrate
Inhibitor
Inducer
Details