Genes for Taste Receptors. Isolation of a Gene for a Sour Taste Receptor.

Taste receptor cells located in taste buds respond to gustatory stimuli using a complex arrangement of receptor molecules, signaling cascades, and ion channels. To depolarize taste receptor cells, ionic stimuli, such as salts and acids (protons), interact directly with apically located ion channels, whereas the second messenger systems via specific taste receptors are important in transducing bitter, sweet, and umami stimuli. In this article, we report the isolation of a cDNA encoding a taste receptor for sourness from a rat circumvallate papilla cDNA library by combined homology and functional expression approaches. Taste receptors for other tastes are also mentioned.