Sodium-dependent, high-affinity amino acid transporter that mediates the uptake of L-glutamate and also L-aspartate and D-aspartate (PubMed:7698742, PubMed:7557442, PubMed:9373176). Functions as a symporter that transports one amino acid molecule together with two or three Na(+) ions and one proton, in parallel with the counter-transport of one K(+) ion. Mediates Cl(-) flux that is not coupled to amino acid transport; this avoids the accumulation of negative charges due to aspartate and Na(+) symport (By similarity). Essential for the rapid removal of released glutamate from the synaptic cleft, and for terminating the postsynaptic action of glutamate (PubMed:9180080). H(+)(out) + K(+)(in) + L-glutamate(out) + 3 Na(+)(out) = H(+)(in) + K(+)(out) + L-glutamate(in) + 3 Na(+)(in) H(+)(out) + K(+)(in) + L-aspartate(out) + 3 Na(+)(out) = H(+)(in) + K(+)(out) + L-aspartate(in) + 3 Na(+)(in) D-aspartate(out) + H(+)(out) + K(+)(in) + 3 Na(+)(out) = D-aspartate(in) + H(+)(in) + K(+)(out) + 3 Na(+)(in) Homotrimer (By similarity). Interacts with AJUBA (By similarity). Detected in brain (PubMed:9180080). Detected in embryonic forebrain, especially in globus pallidus, perirhinal cortex, lateral hypothalamus, hippocampus, and on fimbria and axonal pathways connecting the neocortex, basal ganglia and thalamus (at protein level) (PubMed:16880397). Isoform GLT1 is expressed in the brain (PubMed:7698742, PubMed:7557442, PubMed:9373176, PubMed:9180080). Isoforms GLT-1A and GLT-1B are expressed in the liver (PubMed:9373176). Contains eight transmembrane regions plus two helical hairpins that dip into the membrane. These helical hairpin structures play an important role in the transport process. The first enters the membrane from the cytoplasmic side, the second one from the extracellular side. During the transport cycle, the regions involved in amino acid transport, and especially the helical hairpins, move vertically by about 15-18 Angstroms, alternating between exposure to the aqueous phase and reinsertion in the lipid bilayer. In contrast, the regions involved in trimerization do not move. Glycosylated. Palmitoylation at Cys-38 is not required for correct subcellular localization, but is important for glutamate uptake activity. No visible phenotype at birth (PubMed:9180080, PubMed:16880397). Mice are born at the expected Mendelian rate, but gain weight more slowly, especially after the first 30 days after birth (PubMed:9180080). Only half of them are still alive 60 days after birth (PubMed:9180080). Death is due to spontaneous epileptic seizures (PubMed:9180080). Besides, mutant mice display neuronal degeneration in the hippocampus CA1 field, probably due to impaired glutamate removal from the synaptic cleft (PubMed:9180080). Glutamate uptake by synaptosomes from mutant mouse brain cortex is reduced by 94% (PubMed:9180080). Mice deficient in both Slc1a2 and Slc1a3 die at about 17 dpc; they display defects in the brain structure that affects the brain cortex, hippocampus and olfactory bulb, due to impaired radial migration of neurons into the cortical plate and disorganization of the radial glial cell arrangement (PubMed:16880397). Belongs to the dicarboxylate/amino acid:cation symporter (DAACS) (TC 2.A.23) family. SLC1A2 subfamily.