Isolation of a multispecific organic anion and cardiac glycoside transporter from rat brain

Noé, B. and Hagenbuch, B. and Stieger, B. and Meier, P. J.. (1997) Isolation of a multispecific organic anion and cardiac glycoside transporter from rat brain. Proceedings of the National Academy of Sciences of the United States of America, Vol. 94, No. 19. pp. 10346-10350.

Full text not available from this repository.

Official URL: http://edoc.unibas.ch/dok/A5261718

Downloads: Statistics Overview


A novel multispecific organic anion transporting polypeptide (oatp2) has been isolated from rat brain. The cloned cDNA contains 3,640 bp. The coding region extends over 1,983 nucleotides, thus encoding a polypeptide of 661 amino acids. Oatp2 is homologous to other members of the oatp gene family of membrane transporters with 12 predicted transmembrane domains, five potential glycosylation, and six potential protein kinase C phosphorylation sites. In functional expression studies in Xenopus laevis oocytes, oatp2 mediated uptake of the bile acids taurocholate (Km approximately 35 microM) and cholate (Km approximately 46 microM), the estrogen conjugates 17beta-estradiol-glucuronide (Km approximately 3 microM) and estrone-3-sulfate (Km approximately 11 microM), and the cardiac gylcosides ouabain (Km approximately 470 microM) and digoxin (Km approximately 0.24 microM). Although most of the tested compounds are common substrates of several oatp-related transporters, high-affinity uptake of digoxin is a unique feature of the newly cloned oatp2. On the basis of Northern blot analysis under high-stringency conditions, oatp2 is highly expressed in brain, liver, and kidney but not in heart, spleen, lung, skeletal muscle, and testes. These results provide further support for the overall significance of oatps as a new family of multispecific organic anion transporters. They indicate that oatp2 may play an especially important role in the brain accumulation and toxicity of digoxin and in the hepatobiliary and renal excretion of cardiac glycosides from the body.
Faculties and Departments:11 Rektorat und Verwaltung > Vizerektorat Forschung
UniBasel Contributors:Meier-Abt, Peter J.
Item Type:Article, refereed
Article Subtype:Research Article
Publisher:National Academy of Sciences
Note:Publication type according to Uni Basel Research Database: Journal article
Related URLs:
Identification Number:
Last Modified:22 Mar 2012 14:23
Deposited On:22 Mar 2012 13:34

Repository Staff Only: item control page