GABRB3

This gene encodes a member of the ligand-gated ionic channel family. The encoded protein is one the subunits of a multi-subunit chloride channel that serves as the receptor for gamma-aminobutyric acid, a major inhibitory neurotransmitter of the mammalian nervous system. This gene is located on the long arm of chromosome 15 in a cluster with two other genes encoding related subunits of the family. This gene may be associated with the pathogenesis of several disorders including Angelman syndrome, Prader-Willi syndrome, nonsyndromic orofacial clefts, epilepsy and autism. Alternatively spliced transcript variants encoding distinct isoforms have been described. [provided by RefSeq, Jul 2013]

Full Name

Gamma-Aminobutyric Acid Type A Receptor Beta3 Subunit

Function

Ligand-gated chloride channel which is a component of the heteropentameric receptor for GABA, the major inhibitory neurotransmitter in the brain (PubMed:18514161, PubMed:22303015, PubMed:26950270, PubMed:22243422, PubMed:24909990).

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:25489750).

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 (By similarity).

The alpha1/beta3/gamma2 receptor exhibits synaptogenic activity (PubMed:25489750).

The alpha2/beta3/gamma2 receptor shows very little or no synaptogenic activity (By similarity).

Functions also as histamine receptor and mediates cellular responses to histamine (PubMed:18281286).

Plays an important role in somatosensation and in the production of antinociception (By similarity).

Biological Process

Cellular response to histamine Source: UniProtKB
Chemical synaptic transmission Source: GO_Central
Chloride transmembrane transport Source: GO_Central
Gamma-aminobutyric acid signaling pathway Source: UniProtKB
Inhibitory synapse assembly Source: UniProtKB
Ion transmembrane transport Source: GO_Central
Nervous system process Source: GO_Central
Regulation of membrane potential Source: GO_Central
Roof of mouth development Source: UniProtKB
Signal transduction Source: GO_Central

Cellular Location

Postsynaptic cell membrane; Cell membrane; Cytoplasmic vesicle membrane

Involvement in disease

Epilepsy, childhood absence 5 (ECA5):
A subtype of idiopathic generalized epilepsy characterized by an onset at age 6-7 years, frequent absence seizures (several per day) and bilateral, synchronous, symmetric 3-Hz spike waves on EEG. Tonic-clonic seizures often develop in adolescence. Absence seizures may either remit or persist into adulthood.
Developmental and epileptic encephalopathy 43 (DEE43):
A form of epileptic encephalopathy, a heterogeneous group of severe early-onset epilepsies characterized by refractory seizures, neurodevelopmental impairment, and poor prognosis. Development is normal prior to seizure onset, after which cognitive and motor delays become apparent. DEE43 inheritance is autosomal dominant.

Topology

Extracellular: 26-245
Helical: 246-267
Cytoplasmic: 268-270
Helical: 271-293
Extracellular: 294-304
Helical: 305-327
Cytoplasmic: 328-450
Helical: 451-472