Multimodal sensory integration of courtship stimulating cues in Drosophila melanogaster

Abstract

Mechanisms for identifying appropriate mating partners are required for any species to survive. In many types of animals, males employ multiple sensory modalities to initially search for females and to subsequently determine if they are fit and/or receptive. In this paper we will detail the multiple types of sensory information that are used to initiate and drive courtship in Drosophila melanogaster and discuss the importance of context in the interpretation of chemosensory cues. We find that food-related olfactory cues increase the salience of the aversive pheromone cis-vaccenyl acetate.

Figure 1

The courtship response to cVA is modulated by both the age of the female and the presence of food odors from yeast, the fly's main food source. (A) Diagram of the behavior chamber. The male and the female are videotaped in an 8 mm diameter × 3 mm high chamber with a mesh floor. Odors are presented in a chamber of the same size below the courting pair so that they have no direct contact with odorants. (B) Courtship in the presence of pheromone and food odor (10% v/v yeast paste). Courtship index (% of a 10-min observation period spent in active courtship, measured as described8) was assessed for 4–5 day old Canton-S wild-type males presented with either a 0 day old immature virgin (iV; white bars) or a 4–5 day old decapitated mature virgin (mVd; gray bars). Odorants presented are indicted below the dotted line in the figure. Odorants (or water as a control) were applied to a disc of filter paper. The order of application for cVA and yeast paste was varied: cVA + yeast indicates cVA was put on top of yeast paste; yeast + cVA indicates cVA was applied first and covered with yeast. Data are presented as mean ± SEM and analyzed by ANOVA with posthoc test for pair-wise comparisons. * indicates P < 0.05 for the comparison to the water control value.