Ligand-gated chloride channel which is a component of the heteropentameric receptor for GABA, the major inhibitory neurotransmitter in the brain (PubMed:18514161, PubMed:22303015, PubMed:26950270, PubMed:22243422, PubMed:24909990). Plays an important role in the formation of functional inhibitory GABAergic synapses in addition to mediating synaptic inhibition as a GABA-gated ion channel (PubMed:25489750). The gamma2 subunit is necessary but not sufficient for a rapid formation of active synaptic contacts and the synaptogenic effect of this subunit is influenced by the type of alpha and beta subunits present in the receptor pentamer (By similarity). The alpha1/beta3/gamma2 receptor exhibits synaptogenic activity (PubMed:25489750). The alpha2/beta3/gamma2 receptor shows very little or no synaptogenic activity (By similarity). Functions also as histamine receptor and mediates cellular responses to histamine (PubMed:18281286). Plays an important role in somatosensation and in the production of antinociception (By similarity). Heteropentamer, formed by a combination of alpha, beta, gamma, delta and rho chains (PubMed:22243422, PubMed:18281286, PubMed:18514161, PubMed:24909990). Can form functional homopentamers (in vitro) (PubMed:22303015). Interacts with UBQLN1 (By similarity). May interact with KIF21B (By similarity). Identified in a complex of 720 kDa composed of LHFPL4, NLGN2, GABRA1, GABRB2, GABRG2 and GABRB3 (By similarity). Interacts with LHFPL4 (By similarity). Interacts with GIT1; this interaction is required for synaptic GABRB3 surface stability and inhibitory synapse strength (By similarity). Isoforms differ in their signal region. GABRB3 variants may be associated with insomnia, a condition of inability to initiate or maintain sleep [MIM:137192]. Disease susceptibility is associated with variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. Belongs to the ligand-gated ion channel (TC 1.A.9) family. Gamma-aminobutyric acid receptor (TC 1.A.9.5) subfamily. GABRB3 sub-subfamily. Forbidden fruit - Issue 56 of March 2005