Claude WICKER-THOMAS
Mecanismes de Communication, NAM, URA 1491, Université de Paris-Sud, Bat. 446.
91405 ORSAY Cedex. FRANCE
The Drosophila pheromonal hydrocarbons are long-chain (20 - 35 carbon) compounds that are on the cuticle surface. In D. melanogaster mature females heptacosadiene is present in high quantity and absent in males and young females and constitutes the main sexual pheromone.
The regulation of Drosophila pheromones and its regulation remain largely unknown. Most pheromonal mutant females are characterized by an accumulation of (!) 7 monoenes paralleled with a decrease in (!) 7,11 dienes. A desaturation step is then blocked in those mutants. The same step step is blocked in decapitated wildtype flies and seems thus to be under a cephalic control.
The regulation of this desaturation step is being studied with two different approaches: firstly the study of the influence of different factors on pheromone biosynthesis; secondly a molecular genetic study of the desaturase(s) that will give more information about its control.