TAS1R3

Taste receptor type 1 member 3 (TAS1R3), also known as T1R3 or GPR70, is a G-protein coupled receptor (GPCR) expressed in taste buds. It forms functional heterodimers: with TAS1R1 to detect umami compounds (e.g., glutamate) and with TAS1R2 to sense sweet substances (sugars, artificial sweeteners). Upon ligand binding, it activates the Gα gustducin pathway, triggering IP3-mediated Ca²⁺ release and neurotransmitter secretion, relaying taste signals to afferent neurons.
Dysregulation of TAS1R3 links to taste disorders (hypogeusia, dysgeusia) and metabolic conditions like obesity—altered sweet taste perception may influence food intake. Drug development focuses on modulators: agonists to enhance taste in patients with taste loss (e.g., chemotherapy-induced), and antagonists to reduce sweet cravings for weight management, though most candidates remain in preclinical stages.