Behavioral and transcriptome analyses reveal the impact of sleep deprivation on mosquito biology

Sleep is well conserved in insects and influences different biological parameters, including cognition, metabolism, reproduction, and immunity. However, little is known about sleep in blood-feeding arthropods and how it impacts disease transmission. Previously, we have established sleep-like states in mosquitoes, characterized by stereotypical body postures, species-specific periods of immobility, reduced response to host stimulation, and the occurrence of sleep rebound following sleep deprivation. Furthermore, our studies showed that sleep deprivation caused the suppression of host landing and blood feeding in Aedes aegypti which are aspects of mosquito biology important in disease transmission. In this current study, we investigated population differences in activity and sleep parameters among 17 Ae. aegypti lines, representing recently collected lines from Africa and some other well-adapted populations. Infrared-based monitoring reveals consistent diurnal activity among the populations, but significant differences in activity and sleep levels, number of sleep bouts, and sleep bout duration were observed. In addition, differences in host preference, ancestry, and human population density were predictors that explained the variations in activity and sleep metrics observed among our African populations. Lastly, we evaluated the influence of sleep deprivation on gene expression profiles in Ae. aegypti using RNA-seq analyses. Functional enrichment analyses of differentially expressed genes in sleep-deprived mosquitoes relative to their control counterparts show processes associated with immune response, cellular developmental process, and neuron differentiation. These results provide an insight into the potential influence of sleep on disease transmission and underscore the need to account for population differences when investigating important aspects of mosquito biology.