Bitter taste receptor research comes of age: from characterization to modulation of TAS2Rs.

The recognition of potentially harmful food components by the gustatory system is important for survival and well-being of vertebrates. The plethora of structurally diverse bitter substances present in nature is recognized by multiple bitter taste receptors belonging to the taste receptor 2 family (TAS2R) of heptahelical receptors resulting in a highly complex mechanism of bitterness perception. In particular, research on human bitter taste receptors allowed the characterization of the receptive range of most of the 25 TAS2Rs, which was a prerequisite for detailed experiments to elucidate the structure-function relationships of TAS2Rs and for the discovery of the first reasonably specific TAS2R antagonists. These new findings will be the focus of the present review.