Taste receptor biology: Taste receptor cells present in taste buds on the tongue express a number of membrane proteins that mediate taste sensation. In humans, bitter taste is one of the five basic taste sensations and is mediated by 25 bitter taste receptors (T2Rs). Recent studies from our group and others have shown that T2Rs are also expressed outside the tongue, including many extraoral tissues such as brain, airways, vasculature, and in pathophysiological conditions such as breast cancer. This suggests that T2Rs possess as yet largely uncharacterized cellular and physiological functions that are in addition to taste sensing. A major focus of our group is on studying the role of these chemosensory receptors in airway diseases such as Cystic Fibrosis and in certain types of cancers.
Identification of novel bitter ligands: Structure-function analysis of T2Rs is also an area of intense investigation by our group members. Most of the T2Rs are activated by a wide variety of plant derived bitter compounds including peptides and advanced glycation end products (AGEs). Therefore, customized proteolysis could be used to generate peptides that activate or deactivate T2Rs. By studying the effects of different peptides, it will be possible to elucidate the structural requirements that determine T2R-activation or deactivation potency of natural peptide sequences. Similarly, AGEs can be custom-produced through optimized in vitro reactions between sugars and peptides followed by structure-function studies. Therefore, a major focus of the research is to determine the structure-function properties of natural peptides and AGEs as T2R agonists or antagonists.