glutamate receptor 2; GluR-2; GluR-B; GluR-K2; glutamate receptor ionotropic, AMPA 2; AMPA-selective glutamate receptor 2 (GRIA2, GLUR2)

Function: - ionotropic glutamate receptor - binding of the excitatory neurotransmitter L-glutamate induces a conformation change, leading to the opening of the cation channel, & thereby converts the chemical signal to an electrical impulse - the receptor then desensitizes rapidly & enters a transient inactive state, characterized by the presence of bound agonist - palmitoylated a) depalmitoylated upon glutamate stimulation b) Cys-610 palmitoylation leads to Golgi retention & decreased cell surface expression c) in contrast, Cys-836 palmitoylation does not affect cell surface expression but regulates stimulation- dependent endocytosis (putative) - may interact with MPP4 - interacts with PRKCABP, GRIP1 & GRIP2 - forms a ternary complex with GRIP1 & CSPG4 - binds to PDZ domain of GRIP1 via C-terminal SVKI motif - receptor binds AMPA (quisqualate) > glutamate > kainate Structure: - homotetramer or heterotetramer of pore-forming glutamate receptor subunits - tetramers may be formed by the dimerization of dimer - belongs to the glutamate-gated ion channel (TC 1.A.10) family Compartment: - cell membrane - cell junction, synapse, postsynaptic cell membrane Alternative splicing: named isoforms=3 Genetics: - RNA editing: modified positions=607 - partially edited - fully edited in brain - heteromerically expressed edited GLUR2 (R) receptor complexes are impermeable to Ca⁺², whereas the unedited (Q) forms are highly permeable to divalent ions

General

glycoprotein ionotropic receptor subunit phosphoprotein

Properties

SIZE: entity length = 883 aa MW = 99 kD COMPARTMENT: plasma membrane MOTIF: exoplasmic domain {1-543} MOTIF: signal sequence {1-24} N-glycosylation site {N256} N-glycosylation site {N370} N-glycosylation site {N406} N-glycosylation site {N413} Glutamate binding {499-501} binding site SITE: 506-506 FOR-BINDING-OF: Glutamate transmembrane domain {544-564} cytoplasmic loop {565-624} MOTIF: cysteine residue {C610} MODIFICATION: palmitate COMPARTMENT: membrane transmembrane domain {625-645} exoplasmic loop {646-812} MOTIF: Glutamate binding {675-676} Ser phosphorylation site {S683} Ser phosphorylation site {S717} binding site SITE: 726-726 FOR-BINDING-OF: Glutamate transmembrane domain {813-833} cytoplasmic domain {834-883} MOTIF: cysteine residue {C836} MODIFICATION: palmitate COMPARTMENT: membrane Tyr phosphorylation site {Y869} Tyr phosphorylation site {Y876} Ser phosphorylation site {S880}

Database Correlations

OMIM 138247 UniProt P42262 PFAM correlations Entrez Gene 2891 Kegg hsa:2891

References

UniProt :accession P42262