Premating Isolation is Determined by Larval Rearing Substrates in Cactophilic Drosophila mojavensis. VII. Effects of Larval Dietary Fatty Acids on Adult Epicuticular Hydrocarbons

Abstract

Low concentrations of dietary triacylglycerols including tristearin, triolein, and tripalmitolein, were assessed to determine their effects during egg to pupal stages on adult epicuticular hydrocarbon (EHC) variation in cactophilic Drosophila mojavensis. Triacylglycerols were added singly and in combination at concentrations of 1%, 3%, and 9% to a lipid-free culture medium. Control diets included Carolina Drosophila and lipid-free media. Egg to adult viability was reduced at triacylglycerol concentrations greater than 1%, except for tristearin. Both triolein and tripalmitolein increased EHC amounts to levels similar to those in combination and control diets. Tristearin caused significantly lower quantities of EHCs in adult flies than triolein or tripalmitolein, consistent with previous studies on reduced tristearin assimilation into adult EHCs. We rejected the hypothesis that unsaturated and saturated triacylglycerols were assimilated into unsaturated and saturated adult EHCs, respectively. Since these triacylglycerols comprise a fraction of known lipids in the columnar cacti used for breeding in nature, and EHCs serve as contact pheromones in D. mojavensis, these and other naturally occurring triacylglycerols may provide a direct causal link between host plant use and patterns of chemically mediated mate choice.

Flexible origin of hydrocarbon/pheromone precursors in Drosophila melanogaster

“…4H ; supplementary Table 6D, F), indicating that alteration of lipid metabolism in the FB affects oenocyte activity. Therefore, to determine whether FA synthesis in the FB plays a role in CHC biogenesis, we used the C564-gal4 driver to knockdown lipid-enriched food to the larvae of the cactophilic Drosophila mojavensis decreases CHC production in adults ( 31 ). Here, we show that this is also the case in the polyphagous D. melanogaster and that the decrease in CHCs impacts sexual communication in adults.…”

Genetic Constraints and the Evolution of Display Trait Sexual Dimorphism by Natural and Sexual Selection

“…Dietary composition has been shown to affect CHC biosynthesis in many insects (Liang and Silverman 2000;Buczkowski et al 2005;Rojas et al 2005), including Drosophila (Etges et al 2006). When D. serrata that have adapted to standard yeast-based larval food are allowed to adapt to a novel corn-based larval food that differs in amino acid content, male and female CHCs evolve independently toward new optima (Rundle et al 2005).…”

Aging modulates cuticular hydrocarbons and sexual attractiveness inDrosophila melanogaster

“…CHC composition in the fly has been shown to respond to external influences, including diet and temperature during development, social interactions and light cycles (Etges et al, 2006;Kent et al, 2008;Krupp et al, 2008;Savarit and Ferveur, 2002). Their levels also fluctuate in a circadian manner, suggesting high rates of turnover (Krupp et al, 2008).…”