G protein alpha s subunit (Gαs or Gs alpha)

The **G protein alpha s subunit (Gαs)** is a signaling protein that functions as the stimulatory alpha subunit of heterotrimeric G proteins. It plays a central role in mediating the cellular response to various hormones and neurotransmitters that signal through G protein-coupled receptors (GPCRs). Upon ligand binding to a GPCR, Gαs exchanges GDP for GTP, dissociates from Gβγ subunits, and activates adenylyl cyclase, leading to the production of cyclic AMP (cAMP). This pathway regulates numerous physiological processes, including metabolism, endocrine function, and neural signaling[4][5][10]. Mutations in the gene encoding Gαs (GNAS) are implicated in several diseases, and aberrant regulation can be exploited by bacterial toxins such as cholera toxin. Gαs is a validated signaling target but not a therapeutic target in the sense of having specific, clinically approved drugs that directly target it as a principal mode of action; most drug interventions modulate Gαs indirectly via GPCRs.

Other names

Gs protein alpha subunitGs alpha subunitGsαGNAS proteinAdenylate cyclase-stimulatory G protein alpha subunit

Activation of membrane-bound adenylyl cyclase, increasing cAMP and activating downstream effectors such as protein kinase A (PKA) Drugs or toxins can act as agonists or antagonists via their receptors, altering Gsα-mediated responses