Molecular characterization of a high-affinity mouse glutamate transporter.

The complete coding sequence of a mouse glutamate transporter (mEAAT2) has been cloned by polymerase chain reaction (PCR) from adult whole-brain total RNA. Southern hybridization analysis of PCR products amplified from templates derived from various murine adult tissues demonstrated that the transcript for mEAAT2 was specific to the central nervous system. High-affinity transport of D-aspartate, Km value (17 +/- 5 microM), was determined in a vaccinia/T7 RNA polymerase expression system. The deduced amino-acid sequence of mEAAT2 shares 96 and 93% identity with the rat and human EAAT2 homologues, respectively.