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
  • depalmitoylated upon glutamate stimulation
  • Cys-610 palmitoylation leads to Golgi retention & decreased cell surface expression
  • 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

More general terms

• ionotropic receptor subunit
• phosphoprotein
• glycoprotein

Database

• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:2891
• OMIM: https://mirror.omim.org/entry/138247
• UniProt: http://www.uniprot.org/uniprot/P42262.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=2891