Molecular and functional characterization of an organic anion transporting polypeptide cloned from human liver.

Article Details

Citation

Kullak-Ublick GA, Hagenbuch B, Stieger B, Schteingart CD, Hofmann AF, Wolkoff AW, Meier PJ

Molecular and functional characterization of an organic anion transporting polypeptide cloned from human liver.

Gastroenterology. 1995 Oct;109(4):1274-82.

PubMed ID
7557095 [ View in PubMed
]
Abstract

BACKGROUND & AIMS: Based on a recently cloned rat liver organic anion transporter, we attempted to clone the corresponding human liver organic anion transporting polypeptide. METHODS: A human liver complementary DNA library was screened with a specific rat liver complementary DNA probe. The human liver transporter was cloned by homology with the rat protein and functionally characterized in Xenopus laevis oocytes. RESULTS: The cloned human liver organic anion transporting polypeptide consists of 670 amino acids and shows a 67% amino acid identity with the corresponding rat liver protein. Injection of in vitro transcribed complementary RNA into frog oocytes resulted in the expression of sodium-independent uptake of [35S]bromosulfophthalein (Michaelis constant [Km], approximately 20 mumol/L), [3H]cholate (Km, approximately 93 mumol/L), [3H]taurocholate (Km, approximately 60 mumol/L), [14C]glycocholate, [3H]taurochenodeoxycholate, and [3H]tauroursodeoxycholate (Km, approximately 19 mumol/L). Northern blot analysis showed cross-reactivity with messenger RNA species from human liver, brain, lung, kidney, and testes. Polymerase chain reaction analysis of genomic DNA from a panel of human-rodent somatic cell hybrids mapped the cloned human organic anion transporter to chromosome 12. CONCLUSIONS: These studies show that the cloned human liver organic anion transporter is closely related to, but probably not identical to, the previously cloned rat liver transporter. Furthermore, its additional localization in a variety of extrahepatic tissues suggests that it plays a fundamental role in overall transepithelial organic anion transport of the human body.

DrugBank Data that Cites this Article

Drug Transporters
DrugTransporterKindOrganismPharmacological ActionActions
Cholic AcidSolute carrier organic anion transporter family member 1A2ProteinHumans
Unknown
Substrate
Inhibitor
Inducer
Details
Taurochenodeoxycholic acidSolute carrier organic anion transporter family member 1A2ProteinHumans
Unknown
Not AvailableDetails
Taurocholic acidSolute carrier organic anion transporter family member 1A2ProteinHumans
Unknown
Substrate
Inhibitor
Inducer
Details
Tauroursodeoxycholic acidSolute carrier organic anion transporter family member 1A2ProteinHumans
Unknown
Not AvailableDetails
Ursodeoxycholic acidSolute carrier organic anion transporter family member 1A2ProteinHumans
Unknown
Substrate
Inhibitor
Inducer
Details
Polypeptides
NameUniProt ID
Solute carrier organic anion transporter family member 1A2P46721Details