Gamma-aminobutyric acid type A receptor subunit gamma-3 (GABRG3)

Gamma-aminobutyric acid type A receptor subunit gamma-3 (GABRG3) is a protein subunit of the GABA(A) receptor, a pentameric, ligand-gated chloride ion channel crucial for fast inhibitory neurotransmission in the central nervous system[1][2][3]. The GABA(A) receptor is assembled from multiple subunits (mainly alpha, beta, gamma, delta, and rho), with the gamma subunits playing a critical role in determining receptor pharmacology and providing binding sites for benzodiazepines and some anesthetics[1][5]. The GABRG3 gene is located on chromosome 15q12, and its product is predominantly expressed in the brain, where it modulates synaptic inhibition by facilitating chloride influx upon GABA binding, leading to cellular hyperpolarization[1][3][5]. Dysfunction or altered expression of GABRG3 and its receptor complex is associated with neurodevelopmental disorders (such as Angelman syndrome, autism spectrum disorder, and Rett syndrome), as well as with epilepsy and altered responses to sedative or anxiolytic medications[1][3][5]. The receptor is pharmacologically targeted by various clinically important drug classes (e.g., benzodiazepines), which act as positive allosteric modulators, as well as by barbiturates, neurosteroids, and alcohols[2][5]. Safety considerations for drugs targeting this receptor include tolerance, dependence, sedation, and risk of withdrawal seizures[2].

Other names

Gamma-aminobutyric acid receptor subunit gamma-3GABA(A) receptor subunit gamma-3GABAAR subunit gamma-3GABA(G) receptor gamma-3

Positive allosteric modulation (e.g. benzodiazepines enhance channel opening); Direct agonism (e.g. GABA acts as the endogenous agonist); Negative allosteric modulation (e.g. inverse agonists or channel blockers)