Expression cloning and characterization of a renal organic anion transporter from winter flounder

Open Access
Publisher Website
Google Scholar
Abstract
The cDNA coding for a renal p‐aminohippurate (PAH) transporter from winter flounder (Pseudopleuronectes americanus), designated fROAT, was cloned by functional expression in Xenopus laevis oocytes. fROAT is approximately 2.8 kbp in length and encodes a protein of 562 amino acids, related to the rat renal organic anion transporter ROAT1/OAT1 and the organic cation transporters OCT1 and OCT2. In oocytes, fROAT mediated probenecid‐sensitive PAH uptake, with a K m for PAH of about 20 μM, and inhibited by external glutarate (GA) (1 mM). The functional characteristics suggest that fROAT is the basolateral PAH/dicarboxylate exchanger of the flounder kidney.