Expression of weight and aggression regulating genes in Drosophila melanogaster after exposure to the behavioural pheromone 11-cis-vaccenyl acetate

Abstract:

Obesity is a growing public health issue with few effective treatments. Many of the human genes involved in weight regulation have homologues in other species. In Drosophila melanogaster, 11-cis-vaccenyl acetate (cVA) is a pheromone shown to affect both aggression and feeding behaviour. The aim of this study was to investigate the effect of cVA exposure on gene expression in wild type flies and to confirm crosses with genetic knockouts in the cVA pathway. The genes studied in the wild type flies were Akh (homologue of glucagon), Dilp2,-3 and -5 (homologues of insulin), Dsk (homologue of cholecystokinin), sNPF (homologue of neuropeptide Y) and TβH. The knockout genes studied were Or65a, Or67d and TβH. RNA was extracted from whole heads, cDNA synthesis was performed and the cDNA was then used in SYBR Green RT-qPCR. The knockout genes were not confirmed, due to methodological problems. The expression of Dilp3, Dilp5 and Dsk were significantly lower in the experimental flies, the expression of the other genes where not affected. The results indicate that exposure to cVA affects the expression of some of the neuropeptides involved in weight regulation. Due to the methodological problems experienced, a recommendation is to confirm the data using different reagents.