The sense of taste involves interaction of a taste molecule with a taste receptor cell, and the process of sensory transduction turns that event into a nerve signal to be sent to the brain. There are several possible ways in which a tastant molecule can interact with the receptor cell, and the molecular mechanisms of sweet taste transduction are not known. There are some particular compounds known to suppress sweet taste, and these taste modifiers provide a useful tool to explore transduction. This small exploratory project will use a novel genetic approach to study sweet taste transduction mechanisms. The model system used is the fruit fly of the genus Drosophila, which is very well known for genetic work. Hawaiian species provide unusually large animals in comparison to most laboratory strains, large enough to neurophysiological testing as well as behavioral work. Behavioral tests will be used to screen for flies that cannot taste specific sugars, and these variants will be bred and the mutant strains maintained. The mutant flies will be compared to the wild types in terms of their behavioral and physiological responses to taste stimuli and the sweet-suppressing compounds. Breeding studies will determine the genetic basis for the responses. Results will provide a new access to sweet taste mutant strains for molecular genetic studies, and will have an impact not only on taste physiology, but also on genetics, on evolutionary and environmental biology, and even on pest control by information gained on the genetics of insect feeding behavior.
