The Effects of Population Density and Knock-downs of Llipid Metabolism Genes on the Expression of Cuticular Hydrocarbons in Drosophila melanogaser

In Drosophila melanogaster, chemical cues in the form of cuticular hydrocarbons play an important role in reproductive behavior. The social and genetic processes that regulate their expression, however, are poorly understood. The social environment has been shown to influence hydrocarbon display. In this study, the effect of population density on the expression of hydrocarbons was evaluated. I demonstrate that the production of certain hydrocarbons depends on the population density in which the animal is reared. Individual hydrocarbons fluctuate in quantity independently from one another but the peaks during a light-dark cycle are static depending mostly on chain length. The regulation of fly hydrocarbons which are density-dependent is shown to be sexually dimorphic. The RNAi knockdown of various putative lipid metabolism genes was also used to study hydrocarbon expression. This study reveals that lipid metabolism genes which are not obvious mediators of HC synthesis influence cuticular hydrocarbon profiles.MAS