TAS1R2

TAS1R2 is a gene that encodes the protein T1R2, a component of the sweet taste receptor. This receptor is a heterodimeric G protein-coupled receptor that also includes the protein T1R3, encoded by the TAS1R3 gene. The T1R2+3 receptor is responsible for the perception of sweetness, including both natural sugars and artificial sweeteners.

Structure

The T1R2 protein is a large, multi-domain protein that spans the cell membrane. It contains a large extracellular domain, a seven-transmembrane domain, and an intracellular domain. The extracellular domain is thought to be involved in ligand binding, while the seven-transmembrane domain is responsible for coupling the receptor to intracellular signaling pathways.

Function

The T1R2+3 receptor is expressed in taste bud cells on the tongue, where it is involved in the perception of sweet taste. When a sweet substance is present in the mouth, it binds to the T1R2+3 receptor, triggering a series of intracellular events that ultimately lead to the perception of sweetness.

The T1R2+3 receptor is also expressed in other tissues, including the gut and pancreas, where it may play a role in glucose homeostasis.

Clinical significance

Mutations in the TAS1R2 gene can lead to a reduced ability to taste sweetness, a condition known as hypogeusia. This can have significant effects on diet and nutrition, as individuals with hypogeusia may consume more sugar in an attempt to compensate for their reduced ability to taste it.

See also

• TAS1R3
• Taste receptor
• G protein-coupled receptor