GLRB

This gene encodes the beta subunit of the glycine receptor, which is a pentamer composed of alpha and beta subunits. The receptor functions as a neurotransmitter-gated ion channel, which produces hyperpolarization via increased chloride conductance due to the binding of glycine to the receptor. Mutations in this gene cause startle disease, also known as hereditary hyperekplexia or congenital stiff-person syndrome, a disease characterized by muscular rigidity. Alternative splicing results in multiple transcript variants.

Full Name

glycine receptor beta

Function

Glycine receptors are ligand-gated chloride channels. GLRB does not form ligand-gated ion channels by itself, but is part of heteromeric ligand-gated chloride channels. Channel opening is triggered by extracellular glycine (PubMed:8717357, PubMed:15302677, PubMed:16144831, PubMed:22715885, PubMed:25445488, PubMed:11929858, PubMed:23238346).

Heteropentameric channels composed of GLRB and GLRA1 are activated by lower glycine levels than homopentameric GLRA1 (PubMed:8717357).

Plays an important role in the down-regulation of neuronal excitability (PubMed:11929858, PubMed:23238346).

Contributes to the generation of inhibitory postsynaptic currents (PubMed:25445488).

Biological Process

Acrosome reaction Source: Ensembl
Adult walking behavior Source: Ensembl
Chemical synaptic transmission Source: UniProtKB
Chloride transmembrane transport Source: UniProtKB
Gamma-aminobutyric acid receptor clustering Source: Ensembl
Ion transmembrane transport Source: GO_Central
Ion transport Source: UniProtKB
Nervous system development Source: UniProtKB
Nervous system process Source: GO_Central
Neuropeptide signaling pathway Source: UniProtKB
Regulation of membrane potential Source: GO_Central
Response to amino acid Source: GO_Central
Righting reflex Source: Ensembl
Signal transduction Source: GO_Central
Startle response Source: UniProtKB
Synaptic transmission, glycinergic Source: GO_Central
Visual perception Source: Ensembl

Cellular Location

Postsynaptic cell membrane; Cell membrane; Cytoplasm; Synapse; Dendrite. Retained in the cytoplasm upon heterologous expression by itself. Coexpression with GPHN promotes expression at the cell membrane (PubMed:12684523). Coexpression with GLRA1, GLRA2 or GLRA3 promotes expression at the cell membrane.

Involvement in disease

Hyperekplexia 2 (HKPX2):
A neurologic disorder characterized by muscular rigidity of central nervous system origin, particularly in the neonatal period, and by an exaggerated startle response to unexpected acoustic or tactile stimuli.

Topology

Extracellular: 23-268
Helical: 269-290
Cytoplasmic: 291-295
Helical: 296-316
Extracellular: 317-327
Helical: 328-348
Cytoplasmic: 349-475
Helical: 476-496