GABBR2 Gene - GABA-B Receptor Subunit 2 | Function, Mutations & Disease

GABBR2 encodes the subunit 2 of the gamma-aminobutyric acid type B (GABAB) receptor, a G-protein-coupled receptor that mediates slow inhibitory neurotransmission in the central nervous system. The functional GABAB receptor is a heterodimer of GABBR1 and GABBR2 subunits; GABBR2 is essential for receptor trafficking, ligand binding, and signal transduction via Gi/o proteins. Mutations in GABBR2 are associated with neurodevelopmental disorders including epileptic encephalopathy, autism spectrum disorder, and Rett-like phenotypes.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• GABAergic synapse (KEGG hsa04727)

• Neuroactive ligand-receptor interaction (KEGG hsa04080)

• GPCR downstream signaling (Reactome R-HSA-388396)

GABBR2 (UniProt O75899) is a 941-amino acid transmembrane protein with a large extracellular N-terminal domain, seven transmembrane helices, and a cytoplasmic C-terminal tail. It forms a functional heterodimer with GABBR1 via coiled-coil interactions in the C-terminal region. GABBR2 couples to Gi/o proteins to inhibit adenylyl cyclase, modulate calcium and potassium channels, and regulate neurotransmitter release. The protein is highly expressed in brain regions involved in learning, memory, and motor control.