Where they breed determines how they bite – Mechanistic links between larval ecology and host-seeking behavior in mosquitoes

Mosquitoes are important vectors of diseases that claim several million lives every year worldwide. As larvae, they occupy diverse habitats and are influenced by many ecological factors that impact their adult life. Interestingly, the magnitude of these effects differs between males and females. Female mosquitoes show remarkable plasticity of body size in response to environmental variability. Also, body size in females strongly correlates with their adult behavior and reproductive traits. Here, we varied levels of intraspecific competition to quantify how larval conditions impacted olfactory responses of virgin and mated adult females seeking hosts for blood. The results suggest that host-seeking preferences are strongly linked to variations in female body size and mating status. Analysis of the head transcriptome of the large and small-sized females, both virgin and mated, reveals differences in genes linked to the onset of host-seeking and olfactory sensitivity. In my talk, I will discuss a novel multi-threaded approach that compares the gene transcripts’ co-expression levels to identify ‘hub genes’ whose expression states likely mediate the links between larval ecology and adult host-seeking in mosquitoes. Using results from the transcriptomic analysis, we are pursuing electrophysiological investigations to understand the neural bases of the observed size and mating status-dependent variability in mosquito host-seeking behavior. These results will be discussed in the context of mosquito vector potential and the ensuing disease consequences.