Gabrb2
Domain
The extracellular domain contributes to synaptic contact formation.
GABAARs subunits share a common topological structure: a peptide sequence made up of a long extracellular N-terminal, four transmembrane domains, intracellular or cytoplasmic domain located between the third and the fourth transmembrane domains.
Function
Beta subunit of the heteropentameric ligand-gated chloride channel gated by gamma-aminobutyric acid (GABA), a major inhibitory neurotransmitter in the brain (PubMed:27129275). 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) (By similarity). When activated by GABA, GABAARs selectively allow the flow of chloride anions across the cell membrane down their electrochemical gradient (By similarity). 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 (PubMed:27129275). Extrasynaptic beta-2 receptors contribute to the tonic GABAergic inhibition (By similarity). Beta-containing GABAARs can simultaneously bind GABA and histamine where histamine binds at the interface of two neighboring beta subunits, which may be involved in the regulation of sleep and wakefulness (By similarity).
Post-translational modifications
Glycosylated.
Sequence Similarities
Belongs to the ligand-gated ion channel (TC 1.A.9) family. Gamma-aminobutyric acid receptor (TC 1.A.9.5) subfamily. GABRB2 sub-subfamily.
Cellular localization
- Postsynaptic cell membrane
- Multi-pass membrane protein
- Cell membrane
- Multi-pass membrane protein
- Cytoplasmic vesicle
Alternative names
Gabrb-2, Gabrb2, Gamma-aminobutyric acid receptor subunit beta-2, GABA(A) receptor subunit beta-2, GABAAR subunit beta-2