Glycine receptors are ligand-gated chloride channels. Channel opening is triggered by extracellular glycine. Channel opening is also triggered by taurine and beta-alanine (PubMed:10762330). Plays a role in the down-regulation of neuronal excitability. Contributes to the generation of inhibitory postsynaptic currents (Probable). Inhibited by strychnine (PubMed:10762330). Homopentamer (in vitro). Heteropentamer composed of GLRA4 and GLRB. Detected in the retina inner plexiform layer, especially at the border between layer three and four (at protein level) (PubMed:17154252). The alpha subunit binds strychnine. Belongs to the ligand-gated ion channel (TC 1.A.9) family. Glycine receptor (TC 1.A.9.3) subfamily. GLRA4 sub-subfamily.