Taste receptor type 2 (bitter taste receptor) (TAS2R)

TAS2R receptors constitute a family of G protein-coupled receptors (GPCRs) found primarily in taste receptor cells of the tongue, where they are responsible for detecting a wide variety of bitter compounds, serving as a warning system against the ingestion of potentially toxic substances[1][3][9]. Humans have about 25 functional TAS2R genes, each detecting a different subset of bitter chemicals; these receptors are highly divergent, allowing the recognition of structurally diverse tastants[1][3][6]. TAS2Rs are also expressed in extraoral tissues—including the airway and gastrointestinal tract—where they participate in additional physiological functions, such as innate immune responses and hormone secretion[9]. Variation in TAS2R genes (polymorphisms) is associated with differences in taste sensitivity, food choices, susceptibility to some infections, and behavioral traits like smoking and alcohol use[5][9]. Drugs and natural compounds acting as agonists or antagonists of TAS2Rs can modulate taste as well as extraoral functions.

Other names

T2RBitter taste receptorTaste receptor type 2TAS2R gene familyHuman bitter taste receptor

Binding of bitter ligands causes conformational change, activates G protein signaling, leads to intracellular calcium mobilization and depolarization of taste receptor cells, thereby initiating neural signals for bitter taste perception\nIn extraoral tissues, can modulate immune responses and hormone secretion