Ligand-gated chloride channel which is a component of the heteropentameric receptor for GABA, the major inhibitory neurotransmitter in the brain (PubMed:27129275). 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:27129275). 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 (PubMed:27129275). The alpha1/beta2/gamma2 receptor, alpha2/beta2/gamma2 receptor and the alpha1/beta3/gamma2 receptor exhibit synaptogenic activity whereas the alpha2/beta3/gamma2 receptor shows very little or no synaptogenic activity (PubMed:27129275). Functions also as histamine receptor and mediates cellular responses to histamine (PubMed:18281286). Allosterically activated by benzodiazepines (By similarity). Activated by pentobarbitol (By similarity). Inhibited by the antagonist bicuculline (By similarity). Inhibited by zinc ions (By similarity). Heteropentamer, formed by a combination of alpha, beta, gamma, delta and rho chains (PubMed:18281286). Interacts with GABARAP (By similarity). Interacts 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 (PubMed:28978485, PubMed:29742426). Interacts with SHISA7; interaction leads to the regulation of GABA(A) receptor trafficking, channel deactivation kinetics and pharmacology (PubMed:31601770). Expressed in brain neurons (at protein level). The extracellular domain contributes to synaptic contact formation. Glycosylated. Palmitoylated by ZDHHC3/GODZ; required for the accumulation of GABA(A) receptors at the postsynaptic membrane of inhibitory GABAergic synapses. This subunit carries the benzodiazepine binding site. Belongs to the ligand-gated ion channel (TC 1.A.9) family. Gamma-aminobutyric acid receptor (TC 1.A.9.5) subfamily. GABRG2 sub-subfamily.