alpha5beta2gamma1

Alpha5beta2gamma1 refers to a putative or characterized subunit composition of the GABA-A receptor, a pentameric ligand-gated ion channel that mediates fast synaptic inhibition in the central nervous system. GABA-A receptors are generally assembled from two alpha, two beta, and one gamma subunits, and the particular combination of subunits determines the receptor’s pharmacological and electrophysiological properties. The alpha5beta2gamma1 composition is defined by the presence of the alpha5 subunit, the beta2 subtype, and the gamma1 subtype, which together shape ligand affinity, gating kinetics, and regional expression patterns compared with more common assemblies such as alpha1beta2gamma2 or alpha4beta2delta.

Benzodiazepines and related modulators typically target GABA-A receptors containing a gamma subunit, at the interface between an alpha and a gamma subunit. Therefore, alpha5beta2gamma1 would be expected to be benzodiazepine-sensitive under most circumstances, although the exact pharmacological profile can vary with the specific alpha5/beta2/gamma1 interfaces and post-translational modifications. Neurosteroids and other positive or negative allosteric modulators may further influence its activity.

Distribution and potential function: Alpha5-containing receptors are enriched in hippocampal and cortical circuits and have been linked to modulation of learning and memory and to tonic inhibition when located extrasynaptically. The beta2 and gamma1 subunits contribute to channel kinetics and synaptic versus extrasynaptic localization. The alpha5beta2gamma1 combination may occur in recombinant systems or specific neuronal populations, but detailed in vivo characterization remains limited.

Clinical and research relevance: As a distinct GABA-A receptor subtype, alpha5beta2gamma1 is of interest for understanding region-specific inhibition and for developing drugs with targeted cognitive and anxiolytic profiles. Further biochemical and electrophysiological studies are needed to define its exact stoichiometry, distribution, and pharmacological fingerprint.