Expression cloning of a rat glutamate transporter

Abstract

A functional cDNA clone for the rat glutamate transporter was isolated by a cloning approach using a Xenopus oocyte expression system. The cDNA sequence predicts a protein of 543 amino acids with 6 putative transmembrane domains. The glutamate transporter shows no sequence similarity to other members of the known neurotransmitter transporter family. Expression of the cDNA clone in Xenopus oocyte indicates that glutamate transport activity is Na⁺- and Cl⁻-dependent and sensitive to selective glutamate transporter inhibitor. The glutamate transporter mRNA is expressed in both the brain and the peripheral tissues at different levels.