Molecular mechanisms of signal reception and transduction in taste and smell are being studied. Synthetic genes for the sweet-tasting proteins are being expressed for production of a high affinity ligands for taste receptor identification and characterization. A soluble binding protein and a G-protein that appear to function in taste discrimination and signal transduction respectively have been expressed and are being studied in situ. A novel G-protein gamma-subunit from the basal (stem) cells and developing neurons of the olfactory and vomeronasal epithelia has been cloned and functional studies are in progress. Several putative olfactory receptors are also being expressed for functional characterization; antibodies are being raised to study these native and recombinant receptors.