Genetic elimination of known pheromones reveals the fundamental chemical bases of mating and isolation in Drosophila
Résumé
Overexpression of the UAS-tra transgene in Drosophila melanogaster females led to the complete elimination of their cuticular pheromones. According to current models of Drosophila behavior, these flies should induce no courtship. In fact, they are still attractive to conspecific males. Three classes of stimuli are shown to induce courtship, with different effects on male behavior: (i) known pheromones produced by control females, (ii) stimuli produced by living control and transgenic flies, and (iii) as-yet-undetermined pheromones present on both control and transgenic flies. Only the latter class of pheromones are required for mating. They appear to represent a layer of ancestral attractive substances present in D. melanogaster and its sibling species; known cuticular pheromones modulate this attractivity positively or negatively. The absence of inhibitory pheromones leads to high levels of interspecific mating, suggesting an important role for these cuticular hydrocarbons in isolation between species.
Mots clés
Animals
Genetically Modified
Crosses
Genetic
Drosophila/genetics/*physiology
Drosophila melanogaster/genetics/*physiology
Female
Fungal Proteins/biosynthesis/genetics
Genotype
HSP70 Heat-Shock Proteins/biosynthesis/genetics/physiology
Heat
Hydrocarbons
Male
Pheromones/genetics/*physiology
Recombinant Fusion Proteins/biosynthesis
Saccharomyces cerevisiae Proteins
Sexual Behavior
Animal/*physiology
Social Isolation
Transcription Factors/biosynthesis/genetics