Glycine receptors are ligand-gated chloride channels. Channel opening is triggered by extracellular glycine (PubMed:15131310, PubMed:20978350). Channel characteristics depend on the subunit composition; heteropentameric channels display faster channel closure (By similarity). Plays an important role in the down-regulation of neuronal excitability. Contributes to the generation of inhibitory postsynaptic currents (PubMed:15131310). Contributes to increased pain perception in response to increased prostaglandin E2 levels (PubMed:15131310). Plays a role in the regulation of breathing rhythm, especially of the duration of the postinspiratory phase (PubMed:20978350). Plays a role in cellular responses to ethanol (By similarity). Inhibited by prostaglandin E2, probably via PKA-mediated phosphorylation at Ser-379 (PubMed:15131310). Homopentamer (in vitro) (By similarity). Heteropentamer composed of GLRA3 and GLRB. Both homopentamers and heteropentamers form functional ion channels, but their characteristics are subtly different (By similarity). Partially colocalizes with GPHN that is known to mediate receptor clustering at postsynaptic membranes. Detected in brainstem, also in neurons that control rhythmic breathing (PubMed:20978350). Detected in superficial laminae of the dorsal horn of the thoracic spinal cord (PubMed:15131310). Detected in dentate gyrus in hippocampus, especially in stratum granulare (PubMed:19723286). Detected in the inner plexiform layer in the retina (at protein level) (PubMed:12975813). Detected in midbrain, thalamus, brain cortex, hippocampus, and at lower levels in cerebellum (PubMed:19723286). The N-terminal domain carries structural determinants essential for agonist and antagonist binding. The channel pore is formed by pentameric assembly of the second transmembrane domain from all five subunits. The cytoplasmic loop is an important determinant of channel inactivation kinetics. Phosphorylated by PKA; this causes down-regulation of channel activity. Dephosphorylated in response to activation of HTR1A signaling; this increases channel activity (PubMed:20978350). Mutant mice are born at the expected Mendelian rate, appear normal and are fertile. They do not display notable alterations in motor coordination and startle response, or other neuromotor defects. Glycinergic postsynaptic inhibitory currents in spinal cord appear unchanged, but are not inhibited by prostaglandin E2, contrary to what is observed with wild-type. Basal nociception is unchanged, but contrary to wild-type, mutant mice do not display increased sensitivity to pain after prostaglandin E2 injection. Likewise, they show a more rapid decrease of the increased pain sensitivity caused by agents that cause local inflammation, such as subcutaneous zymosan injection (PubMed:15131310). Mutant mice display altered phrenic nerve activity, resulting in an irregular breathing rhythm that affects especially the duration of the postinspiratory phase. Contrary to wild-type, their respiratory rhythm is not accelerated by serotonin (PubMed:20978350). 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. GLRA3 sub-subfamily.