6533b837fe1ef96bd12a23b1

RESEARCH PRODUCT

effects of early combined pheromone and food exposure on the behavioral development of adult drosophila melanogaster

subject

description

In Drosophila melanogaster, pheromonal communication is mainly mediated through sex-specific cuticular hydrocarbons (and derived compounds) and the male lipidic pheromone 11 - cis - Vaccényl Acétate (cVA). When deposited together on the feeding substrate they attract conspecifics males and females, promoting mating and collective behaviors. Initially described as stereotyped, recent findings showed that adult response to pheromones could be plastic and depend on the juvenile experience of an individual (i.e. imprinting). In this context, we studied cVA imprinting through its aggregative effect in individuals whose imprinting has been manipulated.The first goal, behavioral, was to study long-range attraction of cVA (or not)-imprinted males and females presented with a dual food choice in a flight tunnel. Foods were either naturally labelled by conspecifics (depositing their pheromonal and microbial compounds) or manually enriched with cVA. This first experiment was completed by the analysis of labeled food headspaces to decipher sources and natures of volatiles odorant compounds attracting Drosophila. This experiment highlighted the necessity of an early larval contact with cVA to modulate adult attraction to the pheromone. However, manual larval exposure to cVA alone was not sufficient to fully restore adult attraction,which may indicate that other compounds are needed in the pheromone imprinting. Food choice finally appeared to be a sex-specific behavior dependent on the nature of the food labelling and the dual food choice presented.The second goal was to study the electrophysiological antennal response of cVA (or not)-imprinted males and females when presented with a short-range puff of the pheromone. Recording showed modulation of the peripheric response according to pre-imaginal exposure to cVA but not the sex. It seems that sex-specific long-range attraction in the flight tunnel is rather explained by the central dimorphism of cVA–neural olfactory system than by a different peripheral detection of the pheromone. Finally, the similarity of peripheric response in unimprinted and manually imprinted individuals to cVA alone support the hypothesis that larval imprinting to cVA needs additional parental compounds to be fully effective in adult.