Excitatory Amino Acid Transporter 4 (EAAT4)

EAAT4 is expressed predominantly in the cerebellum, has high affinity for the excitatory amino acids L-aspartate and L-glutamate. When stimulated by these amino acids, EAAT4 conducts chloride ions.Excitatory amino acid transporters (EAATs) in the central nervous system maintain extracellular glutamate concentrations below excitotoxic levels and may limit the activation of glutamate receptors. The transport activity encoded by EAAT4 has high apparent affinity for L-aspartate and L-glutamate, and has a pharmacologic profile consistent with previously described cerebellar transport activities. In Xenopus oocytes expressing EAAT4, L-aspartate and L-glutamate elicited a current predominantly carried by chloride ions. This chloride conductance was not blocked by components that block endogenous oocyte chloride channels.