Gamma-aminobutyric acid receptor subunit gamma-2

UniProtKB accession:  P18508

Grouped By:  Matching UniProtKB accession

UniProtKB description:  Gamma subunit of the heteropentameric ligand-gated chloride channel gated by gamma-aminobutyric acid (GABA), a major inhibitory neurotransmitter in the brain (PubMed:2561970, PubMed:30044221). GABA-gated chloride channels, also named GABA(A) receptors (GABAAR), consist of five subunits arranged around a central pore and contain GABA active binding site(s) located at the alpha and beta subunit interface(s) (PubMed:30044221). When activated by GABA, GABAARs selectively allow the flow of chloride anions across the cell membrane down their electrochemical gradient (PubMed:2561970, PubMed:30044221). Gamma-2/GABRG2-containing GABAARs are found at both synaptic and extrasynaptic sites (PubMed:9464994). Chloride influx into the postsynaptic neuron following GABAAR opening decreases the neuron ability to generate a new action potential, thereby reducing nerve transmission (By similarity). GABAARs containing alpha-1 and beta-2 or -3 subunits exhibit synaptogenic activity; the gamma-2 subunit being necessary but not sufficient to induce rapid synaptic contacts formation (By similarity). Extrasynaptic gamma-2-containing receptors contribute to the tonic GABAergic inhibition (PubMed:9464994). GABAARs function also as histamine receptor where histamine binds at the interface of two neighboring beta subunits and potentiates GABA response in a gamma-2 subunit-controlled manner (By similarity).