The desaturase1 gene affects reproduction before, during and after copulation in Drosophila melanogaster

摘要

Desaturase1 (desat1) is one of the few genes known to be involved in the two complementary aspects of sensory communication - signal emission and signal reception - in Drosophila melanogaster. In particular, desati is necessary for the biosynthesis of major cuticular pheromones in both males and females. It is also involved in the male ability to discriminate sex pheromones. Each of these two sensory communication aspects depends on distinct desati putative regulatory regions. Here, we used (i) mutant alleles resulting from the insertion/excision of a transposable genomic element inserted in a desati regulatory region, and (ii) transgenics made with desati regulatory regions used to target desati RNAi. These genetic variants were used to study several reproduction-related phenotypes. In particular, we compared the fecundity of various mutant and transgenic desati females with regard to the developmental fate of their progeny. We also compared the mating performance in pairs of flies with altered desati expression in various desat1-expressing tissues together with their inability to disengage at the end of copulation. Moreover, we investigated the developmental origin of altered sex pheromone discrimination in male flies. We attempted to map some of the tissues involved in these reproduction-related phenotypes. Given that desati is expressed in many brain neurons and in non-neuronal tissues required for varied aspects of reproduction, our data suggest that the regulation of this gene has evolved to allow the optimal reproduction and a successful adaptation to varied environments in this cosmopolitan species.