Na+-coupled neutral amino acid transporter 2 (amino acid transporter A2, system A transporter 1, system A amino acid transporter 2, system N amino acid transporter 2, solute carrier family 38 member 2, protein 40-9-1, SLC38A2, ATA2, KIAA1382, SAT2, SNAT2)

Function: - Na⁺-dependent amino acid transporter - mediates the saturable, pH-sensitive & electrogenic cotransport of neutral amino acids & Na⁺ ions with a stoichiometry of 1:1 - may function in the transport of amino acids at the blood- brain barrier & in the supply of maternal nutrients to the fetus through the placenta - inhibited by N-methyl-D-glucamine & probably choline - polyubiquitination by NEDD4L regulates the degradation & the activity of SLC38A2 (putative) Kinetic parameters: - KM=0.39 mM for 2-methylamino-isobutyric acid (pH 8.0) Structure: - belongs to the amino acid/polyamine transporter 2 family Compartment: - cell membrane - insulin promotes recruitment to the plasma membrane from a pool localized in the trans-Golgi network or endosomes - nriched in the somatodendritic compartment of neurons, - detected at the axonal shaft but excluded from nerve terminal Alternative splicing: named isoforms=2 Expression: - ubiquitously expressed - widely expressed in the central nervous system with higher concentrations in caudal regions - expressed by glutamatergic & GABAergic neurons together with astrocytes & other non-neuronal cells in cerebral cortex (at protein level) - up-regulated upon hypertonic conditions & amino acid deprivation Note: - depletion of SCL38A2 by siRNA prevents the recovery of cells from hypertonic stress

General

glycoprotein membrane protein phosphoprotein solute carrier family 38 (SLC38, SLC38A)

Properties

SIZE: entity length = 506 aa MW = 56 kD COMPARTMENT: golgi MOTIF: Regulates protein turnover upon amino acid deprivation {1-96} MOTIF: cytoplasmic domain {1-76} Tyr phosphorylation site {Y20} Tyr phosphorylation site {Y41} transmembrane domain {77-97} exoplasmic loop {98-102} transmembrane domain {103-123} cytoplasmic loop {124-158} transmembrane domain {159-179} exoplasmic loop {180-188} transmembrane domain {189-209} cytoplasmic loop {210-217} transmembrane domain {218-238} exoplasmic loop {239-292} MOTIF: N-glycosylation site {N258} N-glycosylation site {N274} transmembrane domain {293-313} cytoplasmic loop {314-329} transmembrane domain {330-350} exoplasmic loop {351-371} transmembrane domain {372-392} cytoplasmic loop {393-413} transmembrane domain {414-434} exoplasmic loop {435-436} transmembrane domain {437-457} cytoplasmic loop {458-474} transmembrane domain {475-495} exoplasmic domain {496-506}

Database Correlations

OMIM 605180 UniProt Q96QD8 Pfam PF01490

References

UniProt :accession Q96QD8