Molecular Aspects of Signal Transduction in the Visual System 
A toxin from the microorganism Bordetella 
pertussis specifically inactivates certain G pro- 
teins. To study the physiological importance of G 
proteins in Drosophila, we produced transgenic 
flies that conditionally express endogenous per- 
tussis toxin. Pertussis toxin induction in adult 
Drosophila alters their visual response and eat- 
ing behavior. We are investigating the molecular 
mechanisms responsible for these phenotypes. 
The long-term objective addressed in these 
projects is to identify biochemical mechanisms 
by which photoreceptors respond to stimuli. 
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