GABRB3
Description
The GABRB3 (gamma-aminobutyric acid type A receptor subunit beta3) is a protein-coding gene located on chromosome 15.
Gamma-aminobutyric acid receptor subunit beta-3 is a protein that in humans is encoded by the GABRB3 gene. It is located within the 15q12 region in the human genome and spans 250kb. This gene includes 10 exons within its coding region. Due to alternative splicing, the gene codes for many protein isoforms, all being subunits in the GABAA receptor, a ligand-gated ion channel. The beta-3 subunit is expressed at different levels within the cerebral cortex, hippocampus, cerebellum, thalamus, olivary body and piriform cortex of the brain at different points of development and maturity. GABRB3 deficiencies are implicated in many human neurodevelopmental disorders and syndromes such as Angelman syndrome, Prader-Willi syndrome, nonsyndromic orofacial clefts, epilepsy and autism. The effects of methaqualone and etomidate are mediated through GABBR3 positive allosteric modulation.
== Gene == The GABRB3 gene is located on the long arm of chromosome 15, within the q12 region in the human genome. It is located in a gene cluster, with two other genes, GABRG3 and GABRA5. GABRB3 was the first gene to be mapped to this particular region.
Ligand-gated chloride channel which is a component of the heteropentameric receptor for GABA, the major inhibitory neurotransmitter in the brain. Plays an important role in the formation of functional inhibitory GABAergic synapses in addition to mediating synaptic inhibition as a GABA-gated ion channel. 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. The alpha1/beta3/gamma2 receptor exhibits synaptogenic activity. The alpha2/beta3/gamma2 receptor shows very little or no synaptogenic activity. Functions also as histamine receptor and mediates cellular responses to histamine. Plays an important role in somatosensation and in the production of antinociception.
GABRB3 is also known as DEE43, ECA5, EIEE43.
Associated Diseases
- Childhood absence epilepsy
- Lennox-Gastaut syndrome
- Epilepsy, childhood absence, susceptibility to, 5
- Epileptic encephalopathy, early infantile, 43
