Gs alpha subunit

The Gs alpha subunit (or Gs protein) is a heterotrimeric G protein subunit that activates the cAMP-dependent pathway by activating adenylate cyclase.

Receptors
The G protein-coupled receptors that couple to this kind of G-protein include:
 * 5-HT receptors types 5-HT4 and 5-HT7
 * ACTH receptor
 * Adenosine receptor types A2a and A2b
 * Arginine vasopressin receptor 2
 * β-adrenergic receptors types β1, β2 and β3
 * Calcitonin receptor
 * Calcitonin gene-related peptide receptor
 * Corticotropin-releasing hormone receptor
 * Dopamine receptors D1-like family (D1 and D5)
 * FSH-receptor
 * Gastric inhibitory polypeptide receptor
 * Glucagon receptor
 * Histamine H2 receptor
 * Luteinizing hormone/choriogonadotropin receptor
 * Melanocortin receptor
 * Parathyroid hormone receptor 1
 * Prostaglandin receptor types D2 and I2
 * Secretin receptor
 * Thyrotropin receptor

Function
The general function of Gs is to activate adenylate cyclase, which, in turn, produces cAMP, which, in turn activates cAMP-dependent protein kinase. Further effects of Gs are thus found in function of cAMP-dependent protein kinase.

It provides a step in signal transduction. Amplification of the signal occurs for instance because the receptor activates several Gs. However, each Gs activates only one adenylate cyclase.