Taste receptor type 1 member 1 (TAS1R1)

Taste receptor type 11 (TASIR) is a class C G protein-coupled receptor that forms a functional heterodimer with Taste receptor type I member III (TASIR). This dimer acts as an amino acid sensor on specialized cells within human taste buds—primarily those located on fungiform papillae at the tip and edges of the tongue—and mediates detection of "umami" flavor from foods rich in L-amino acids such as glutamate. The functional unit responds specifically to L-amino acids but not D-enantiomers. The activity requires both subunits; neither functions independently outside their dimeric complex. Variations in expression or sequence may underlie individual differences in umami sensitivity. While primarily studied for its role in gustatory signaling, there is emerging interest regarding its broader physiological relevance beyond oral sensation[1][3][5].

Other names

TAS1R1T1R1G protein-coupled receptor 70 (GPR70)TR1gm148

For antagonists like lactisole: - Inhibition/antagonism at the TIR/TASIR heterodimer blocks signal transduction triggered by umami stimuli such as monosodium glutamate or L-glutamine. For potentiators like cyclamate: - Allosteric modulation enhances response to natural ligands without direct activation.