Olfactory transduction and taste processing in Drosophila

We completed two separate studies examining chemosensation in Drosophila. The first study investigated taste processing. It was our aim in this study to identify and characterize higher-order gustatory neurons. Our strategy for tackling this problem involved complementary functional and anatomical approaches. First, we used calcium imaging to screen for cells responding to stimulation of gustatory receptor neurons. Second, we used photo-activatable GFP to localize the cell bodies of neurons innervating the gustatory neuropil. Third, based on the information we gained from these imaging experiments, we were able to identify some promising Gal4 lines that labeled candidate gustatory neurons. Fourth and finally, we made whole-cell patch clamp recordings from these candidate gustatory neurons while stimulating the proboscis with tastants. Unfortunately, none of these candidates turned out to be gustatory neurons. However, this study illustrates a flexible and powerful general approach to identifying and characterizing sensory neurons in the Drosophila brain.