Drosophila Food-Associated Pheromones: Effect of Experience, Genotype and Antibiotics on Larval Behavior.

Julien Thibert,Jérôme Cortot,Jean-Pierre Farine,Jean-François Ferveur

doi:10.1371/journal.pone.0151451

Abstract

Animals ubiquitously use chemical signals to communicate many aspects of their social life. These chemical signals often consist of environmental cues mixed with species-specific signals—pheromones—emitted by conspecifics. During their life, insects can use pheromones to aggregate, disperse, choose a mate, or find the most suitable food source on which to lay eggs. Before pupariation, larvae of several Drosophila species migrate to food sources depending on their composition and the presence of pheromones. Some pheromones derive from microbiota gut activity and these food-associated cues can enhance larval attraction or repulsion. To explore the mechanisms underlying the preference (attraction/repulsion) to these cues and clarify their effect, we manipulated factors potentially involved in larval response. In particular, we found that the (i) early exposure to conspecifics, (ii) genotype, and (iii) antibiotic treatment changed D. melanogaster larval behavior. Generally, larvae—tested either individually or in groups—strongly avoided food processed by other larvae. Compared to previous reports on larval attractive pheromones, our data suggest that such attractive effects are largely masked by food-associated compounds eliciting larval aversion. The antagonistic effect of attractive vs. aversive compounds could modulate larval choice of a pupariation site and impact the dispersion of individuals in nature.

Highlights

To develop and reproduce, animals need to perceive multimodal sensory signals informing them on the quality of their environment and on the presence and reproductive status of conspecifics [1]
After 5 min of test, Cs larvae showed a preference for plain food (PF), and this marked difference increased with time (Fig 2B)
At 30 min, 67% larvae aggregated on both food patches with a clear preference to PF compared to CsLF (45.7 and 21.3%, respectively), whereas pupae were distributed on the two food patches

Summary

Introduction

Animals need to perceive multimodal sensory signals informing them on the quality of their environment and on the presence and reproductive status of conspecifics [1]. Both environmental and species-specific cues often combine their effect to elicit the behavioral response in the receiver animal [2, 3, 4]. Pheromones are involved in many social behaviors occurring from larval to adult life. In adults, they can modulate aggregation, mating and aggression [7, 8, 9].

Methods

Results

Conclusion