Genetic analysis of chemosensory perception in Drosophila

Drosophila, like the Brahmin, is born twice, first from the egg as a maggot, then from the pupa as an imago. In both of its incarnations the fly's olfactory behavior undergoes profound changes with age and experience. An important problem is to distinguish between innate and acquired behavior. This is a difficult and, in several respects, an unsettled issue. Understanding adaptive behavior and establishing its neural correlates is the focus of our group's interest. As a part of this effort we are studying learning and memory in larva and imago.

Some years ago we began to investigate imaginal conditioning, a process by which, in the first few days after eclosion, the fly learns to distinguish between attractants and repellents. It develops attraction towards chemicals to which it is exposed and an increased aversion to odors it has not experienced (these reports, 1999). In the following summaries, Bilal Rashid, Farzana Anjum and Jawaid Ahsan describe mutants, which affect imaginal conditioning. Tuhin Chakraborty and Sunil Prabhakar have found that imaginal conditioning is correlated with an increased peripheral sensory response (EAG). Abu Baker and Gayatri Ranganathan have analyzed shock avoidance learning in the larva to separate various components of olfactory memory. The experiment by Annapoorna Bhat on co-induction is our first attempt to develop psychophysics of odor perception with Drosophila.