Taste receptor type 2 member (TAS2R)

The taste receptor type 2 members (TAS2Rs, also called T2Rs) constitute a large family of G protein-coupled receptors responsible primarily for the detection of bitter compounds. In humans there are about 25 functional TAS2R genes. These receptors are expressed on taste cells within taste buds on the tongue and palate epithelium but also found throughout extraoral tissues including the gastrointestinal tract, lungs, brain, and others. Their primary biological function is chemosensation—detecting potentially harmful substances such as plant alkaloids or toxins by mediating aversive ("bitter") taste signals. Activation occurs when a ligand binds to the extracellular domain of a TAS2R protein; this triggers coupling with specific G-proteins like gustducin or related subunits leading to increased intracellular calcium levels and subsequent signal transduction events. Beyond their role in oral sensation, some TAS2Rs have been implicated in physiological processes such as airway smooth muscle relaxation/vasodilation/vasoconstriction depending on tissue context, regulation of gastric acid secretion, hormone release from enteroendocrine cells, and possibly cancer biology. Many natural products—including denatonium benzoate and phenylthiocarbamide—are known agonists. The diversity among species is high due to rapid evolutionary expansion. As written ("family"), this entry refers collectively rather than specifically—each individual gene/protein should be referenced by its full name/number for structured data purposes. If you need information about a specific member—for example "Taste receptor type 2 member 38"—please specify which one.

Other names

TAS2RT2RBitter taste receptor

Agonists bind to the extracellular domain of TAS2Rs, activating intracellular G-protein signaling pathways that lead to increased intracellular calcium and downstream cellular responses.