Component of the heteropentameric receptor for GABA, the major inhibitory neurotransmitter in the vertebrate brain. Functions also as histamine receptor and mediates cellular responses to histamine. Functions as receptor for diazepines and various anesthetics, such as pentobarbital; these are bound at a separate allosteric effector binding site. Functions as ligand-gated chloride channel. Binds UBQLN1 (By similarity). Heteropentamer, formed by a combination of alpha, beta, gamma, delta and rho chains. Interacts with KCTD8, KCTD12 and KCTD16; this interaction determines the pharmacology and kinetics of the receptor response, the KCTD proteins markedly accelerating the GABA-B response, although to different extents (By similarity). 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. GABRB1 sub-subfamily. Forbidden fruit - Issue 56 of March 2005