ASTMH 2016, Kristine Werling: “The role of Ecdysone Receptor in Anopheles gambiae mosquito post-mating biology”

In collaboration with ASTMH, Image Audiovisuals, and session presenters, MESA brings you this webcast from the 65th ASTMH annual meeting in Atlanta, November 2016.

Title: “The role of Ecdysone Receptor in Anopheles gambiae mosquito post-mating biology”

Speaker: Kristine Werling, Harvard T.H. Chan School of Public Health

Session information: Scientific Session 144: “Mosquitoes: Molecular Genetics and Genomics”

Wednesday, 16 November, 1:45 – 3:30, Marriott – Room A602

Abstract:

The Anopheles gambiae mosquito is responsible for infecting millions of people with malaria each year throughout Africa. Female Anophelines mate a single time in their life making reproduction a crucial point in their life cycle, and a potential target for vector control. The critical insect steroid hormone, 20-hydroxyecdysone (20E), is essential for regulating larval development and egg production in numerous insect species. Recently, our lab identified multiple novel roles for 20E in An. gambiae reproduction. We demonstrated that sexual transfer of 20E during copulation is necessary and sufficient to induce two key female post-mating phenotypes: oviposition and refractoriness to multiple matings. Here we show that male-transferred 20E induces these phenotypes by initiating signaling cascades following its interaction with specific receptors localized to the female reproductive tissues. Ecdysone Receptor (EcR) is known to be an ecdysone-responsive nuclear receptor regulating 20E signaling during larval development, metamorphosis, and adult female vitellogenesis. Our findings suggest that EcR in An. gambiae is responsible for regulating 20E-induced oviposition, while female mating refractoriness is induced through a novel, yet unidentified, 20E receptor. We have also discovered that in an EcR depleted background, females fail to store sperm. This sensitized genetic background can be used to provide important biological insights into the mechanism of sperm storage – a critical process for the female’s lifelong fertility. Overall, understanding the mechanisms through which male-transferred 20E induces vast transcriptional and physiological changes in the female An. gambiae mosquito can not only advance knowledge of unique vector reproductive biology, but it can also reveal novel biological targets for mosquito control.