Taste receptor type 2 member 42 (TAS2R42)

Taste receptor type 2 member 42 (TAS2R42) is a G protein-coupled receptor (GPCR) that functions primarily as a bitter taste receptor in humans. It is encoded by the TAS2R42 gene and is linked to the detection of bitter compounds, acting via a gustducin-mediated signaling cascade similar to other type 2 taste receptors. TAS2R42 is mainly known for its role in sensory perception within taste buds, but like other TAS2Rs, may also be expressed in extraoral tissues such as the gastrointestinal tract, where it could participate in sensing the chemical composition of ingested substances and contribute to physiological responses outside the oral cavity. Its activity results in intracellular signaling that ultimately transmits information about bitter substances to the nervous system for taste perception. There are emerging but yet unconfirmed associations between TAS2R42 activity and diseases such as submandibular gland cancer, and it may play a wider role in metabolism and immune system regulation, though concrete pathological or therapeutic links are still under research.

Other names

Taste receptor type 2 member 42TAS2R42T2R42Taste receptor type 2 member 55TAS2R55T2R55T2R24hT2R55candidate taste receptor hT2R55

Upon binding of a bitter compound (agonist), the receptor activates the heterotrimeric G protein gustducin. Downstream, this triggers phospholipase C-β2 (PLCβ2), leading to inositol triphosphate (IP₃) generation, release of intracellular calcium, activation of TRPM5 channels, cell depolarization, and transmission of the taste signal. The described pathway applies generally to type 2 taste receptors and is inferred for TAS2R42 by sequence similarity.