Gria1
Domain
The M4 transmembrane segment mediates tetramerization and is required for cell surface expression.
Function
Ionotropic glutamate receptor that functions as a ligand-gated cation channel, gated by L-glutamate and glutamatergic agonists such as alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), quisqualic acid, and kainic acid (PubMed:1699805). L-glutamate acts as an excitatory neurotransmitter at many synapses in the central nervous system. Binding of the excitatory neurotransmitter L-glutamate induces a conformation change, leading to the opening of the cation channel, and thereby converts the chemical signal to an electrical impulse upon entry of monovalent and divalent cations such as sodium and calcium. The receptor then desensitizes rapidly and enters in a transient inactive state, characterized by the presence of bound agonist. In the presence of CACNG2 or CACNG4 or CACNG7 or CACNG8, shows resensitization which is characterized by a delayed accumulation of current flux upon continued application of L-glutamate. Calcium (Ca(2+)) permeability depends on subunits composition and, heteromeric channels containing edited GRIA2 subunit are calcium-impermeable. Also permeable to other divalents cations such as strontium(2+) and magnesium(2+) and monovalent cations such as potassium(1+) and lithium(1+) (By similarity).
Post-translational modifications
Phosphorylated at Ser-645. Phosphorylated at Ser-710 by PKC. Phosphorylated at Ser-849 by PKC, PKA and CAMK2. Phosphorylated at Ser-863 by PKC, PKA and PRKG2 (By similarity). Phosphorylation of Ser-863 is reduced by induction of long-term depression and increased by induction of long-term potentiation (PubMed:23676497).
Palmitoylated. Depalmitoylated by CPT1C and upon L-glutamate stimulation. ZDHHC3/GODZ specifically palmitoylates Cys-603, which leads to Golgi retention and decreased cell surface expression (PubMed:16129400). In contrast, Cys-829 palmitoylation does not affect cell surface expression but regulates stimulation-dependent endocytosis (PubMed:16129400).
Sequence Similarities
Belongs to the glutamate-gated ion channel (TC 1.A.10.1) family. GRIA1 subfamily.
Tissue Specificity
Expressed in the outer plexiform layer of the retina of the eye (at protein level) (PubMed:28334377). Expressed in the forebrain and hippocampus (at protein level) (PubMed:31651360).
Cellular localization
- Cell membrane
- Multi-pass membrane protein
- Endoplasmic reticulum membrane
- Multi-pass membrane protein
- Postsynaptic cell membrane
- Multi-pass membrane protein
- Postsynaptic density membrane
- Multi-pass membrane protein
- Cell projection
- Dendrite
- Cell projection
- Dendritic spine
- Early endosome membrane
- Multi-pass membrane protein
- Recycling endosome membrane
- Multi-pass membrane protein
- Presynapse
- Synapse
- Interaction with CACNG2, CNIH2 and CNIH3 promotes cell surface expression. Colocalizes with PDLIM4 in early endosomes. Displays a somatodendritic localization and is excluded from axons in neurons (PubMed:18341993). Localized to cone photoreceptor pedicles (PubMed:28334377).
Alternative names
Glur1, Gria1, Glutamate receptor 1, GluR-1, AMPA-selective glutamate receptor 1, GluR-A, GluR-K1, GluA1