CAREER: Regulation of female mating receptivity in Aedes aegypti mosquitoes

Mosquitoes can spread serious diseases to people when they bite, including dengue, chikungunya, and malaria. As mosquito populations expand into new areas, more people are at risk. One effective strategy to reduce disease transmission is to reduce mosquito populations by stopping them from successfully mating and reproducing. Some programs already release sterile male mosquitoes to reduce population size. These males can mate with females, but no offspring are produced. However, scientists still do not fully understand how mosquito mating behavior works, which can limit how effective these strategies are. Our research aims to better understand what signals and behaviors control successful mating in mosquitoes. We are especially interested in how these behaviors may differ among mosquito groups living in different environments. To investigate this, we will collaborate with a Vector Control Agency in Florida to collect mosquitoes from different regions, where habitats vary and may influence how mosquitoes mate. This work will help improve mosquito control strategies by identifying when and where sterile male releases may be effective, especially in areas where female mosquitoes are unlikely to mate more than once. In addition, understanding the biology behind mating could reveal new ways to reduce mosquito populations, such as methods that "switch off" a female mosquito's drive to mate. As part of this research experience, undergraduate trainees will assist with field collections and laboratory experiments, and will also participate in oral and written presentations, as well as mock interviews to prepare for graduate training as members of the STEM workforce. This project advances NSF's priorities in Biotechnology. In Aedes aegypti, females typically mate once and store sufficient sperm to fertilize all eggs produced over their lifetime. During mating, males also transfer proteinaceous factors that induce long-lasting suppression of female receptivity, ensuring exclusive paternity. Although our group previously identified a regulator of short-term post-mating receptivity suppression, the mechanisms by which females detect mating status and initiate and maintain long-term refractoriness remain poorly understood. The goal of this project is to define the molecular and neural mechanisms that link mating status to sustained changes in female behavior. We hypothesize, based on preliminary data, that receptor-expressing cells in females detect male-derived proteins transferred during copulation and relay this information to neural circuits that suppress receptivity. To test this hypothesis, we will pursue three research aims: (1) identify receptors responsive to male-derived, paternity-enforcing factors using a multiplexed high-throughput in vitro screening platform; (2) anatomically map cells expressing candidate receptors using genetic labeling and immunohistochemistry; and (3) functionally investigate candidate receptors and associated circuits using pharmacological and genetic perturbations, coupled with behavioral and paternity assays. Together, these studies will identify the sensory and circuit-level basis of post-mating behavioral plasticity in female mosquitoes. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.