TAS2R5

TAS2R5 is a gene that encodes a member of the TAS2R (taste receptor, type 2) family of G protein-coupled receptors (GPCRs). These receptors are primarily located on the taste receptor cells of the tongue, where they mediate the perception of bitter taste. The TAS2R family is characterized by a relatively high degree of sequence diversity between members, which allows for the detection of a wide range of bitter-tasting compounds.

The specific ligands (bitter compounds) that activate TAS2R5 are not fully characterized, but like other TAS2Rs, it is believed to bind to specific bitter molecules present in food and other substances. Upon activation, TAS2R5 triggers an intracellular signaling cascade involving G proteins and downstream effectors. This cascade ultimately leads to depolarization of the taste receptor cell and transmission of a signal to the brain, resulting in the perception of bitterness.

Genetic variation in the TAS2R5 gene can lead to differences in bitter taste sensitivity among individuals. Single nucleotide polymorphisms (SNPs) and other genetic variations in this gene can affect the receptor's affinity for certain bitter compounds, leading to differences in the perceived intensity of bitterness. These variations may contribute to individual preferences for certain foods and drinks.

While primarily expressed in taste receptor cells, some evidence suggests that TAS2Rs, including TAS2R5, may also be expressed in other tissues, such as the gastrointestinal tract and the respiratory system. The potential function of TAS2R5 and other taste receptors in these extra-oral tissues is an area of ongoing research. It has been hypothesized that they may play a role in innate immune responses or the regulation of digestive processes by detecting and responding to harmful compounds.