Aliases for GABBR1 Gene
External Ids for GABBR1 Gene
Previous GeneCards Identifiers for GABBR1 Gene
This gene encodes a receptor for gamma-aminobutyric acid (GABA), which is the main inhibitory neurotransmitter in the mammalian central nervous system. This receptor functions as a heterodimer with GABA(B) receptor 2. Defects in this gene may underlie brain disorders such as schizophrenia and epilepsy. Alternative splicing generates multiple transcript variants, but the full-length nature of some of these variants has not been determined. [provided by RefSeq, Jan 2016]
GeneCards Summary for GABBR1 Gene
GABBR1 (Gamma-Aminobutyric Acid Type B Receptor Subunit 1) is a Protein Coding gene. Diseases associated with GABBR1 include Childhood Absence Epilepsy and Temporal Lobe Epilepsy. Among its related pathways are GABA receptor activation and Signaling by GPCR. Gene Ontology (GO) annotations related to this gene include G protein-coupled receptor activity and G protein-coupled GABA receptor activity. An important paralog of this gene is GABBR2.
UniProtKB/Swiss-Prot Summary for GABBR1 Gene
Component of a heterodimeric G-protein coupled receptor for GABA, formed by GABBR1 and GABBR2 (PubMed:9872316, PubMed:9872744, PubMed:15617512, PubMed:18165688, PubMed:22660477, PubMed:24305054). Within the heterodimeric GABA receptor, only GABBR1 seems to bind agonists, while GABBR2 mediates coupling to G proteins (PubMed:18165688). Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of down-stream effectors, such as adenylate cyclase (PubMed:10906333, PubMed:10773016, PubMed:10075644, PubMed:9872744, PubMed:24305054). Signaling inhibits adenylate cyclase, stimulates phospholipase A2, activates potassium channels, inactivates voltage-dependent calcium-channels and modulates inositol phospholipid hydrolysis (PubMed:10075644). Calcium is required for high affinity binding to GABA (By similarity). Plays a critical role in the fine-tuning of inhibitory synaptic transmission (PubMed:9844003). Pre-synaptic GABA receptor inhibits neurotransmitter release by down-regulating high-voltage activated calcium channels, whereas postsynaptic GABA receptor decreases neuronal excitability by activating a prominent inwardly rectifying potassium (Kir) conductance that underlies the late inhibitory postsynaptic potentials (PubMed:9844003, PubMed:9872316, PubMed:10075644, PubMed:9872744, PubMed:22660477). Not only implicated in synaptic inhibition but also in hippocampal long-term potentiation, slow wave sleep, muscle relaxation and antinociception (Probable). Activated by (-)-baclofen, cgp27492 and blocked by phaclofen (PubMed:9844003, PubMed:9872316, PubMed:24305054).
Isoform 1E may regulate the formation of functional GABBR1/GABBR2 heterodimers by competing for GABBR2 binding. This could explain the observation that certain small molecule ligands exhibit differential affinity for central versus peripheral sites.
GABAB receptors are metabotropic G-protein-coupled receptors responsible for mediating the inhibitory effects of GABA alongside ionotropic GABAA and GABAA-rho receptors. They exist as heterodimers of GABAB1 and GABAB2 subunits, with both required for function.