Changes in foraging gene expression of female Aedes aegypti (Diptera: Culicidae) are associated with physiological states and locomotor activity

The expression of the gene denominated foraging (for) has been associated with locomotor activity and foraging behavior in several insect species. In the mosquito Aedes aegypti, however, the expression patterns of for orthologue (Aafor) and its role in the mosquito locomotor activity and foraging behavior are unknown. In this study, we quantified Aafor gene expression in adult female A. aegypti across different ages and physiological states. We silenced Aafor expression using RNA interference (RNAi) via microinjection of a double-stranded RNA (dsAafor) and monitored females’ locomotor activity under controlled photoperiods. RNAi-treated females exhibited enhanced locomotor activity compared with control females at the morning peak of activity from the 4th to the 6th days post-microinjection and, at the evening peak throughout the entire observation period. Treatment with RNAi enhanced locomotor activity similar to the effect of a pharmacological cGMP-PKG activator (guanosine-3’-5’-cyclic monophosphate sodium salt; C10H11N5NaO7P) at the evening peak. However, neither treatment altered circadian parameters or the free-running period of females’ locomotor activity. The results indicate that expression of Aafor is reduced after insemination, enhanced after blood-feeding, and suggest Aafor expression is negatively associated with the female’s locomotor activity. Nevertheless, expression changes do not modify circadian rhythms of locomotor activity.