Max Planck

Mosquito-borne illnesses cause more than 1 million deaths annually, making the mosquito the world’s deadliest animal. Mosquito control has historically relied on the use of insecticides, which negatively impact the environment and has led to an increase in insecticide resistance among mosquito populations, necessitating the development of alternative control methods. One promising area to combat mosquitoes and the diseases they spread is to suppress their ability to reproduce. However, the male and female molecules required for optimal fertility, and the physiological processes that lead to progeny generation, first need to be identified in mosquito vectors of disease.

Reproduction is complex and requires numerous interactions between males and females for the successful generation of progeny. Prior to the physical act of mating, a series of male-female behavioral interactions occur important for the localization, recognition, and attraction of opposite-sexed individuals of the same species. When a female accepts a male, she will allow him to copulate, and males transfer seminal fluid—a complex mixture of sperm, seminal fluid proteins (SFPs), and other small molecules—to the female during mating. When copulation ends, male-female interactions continue at the molecular level inside the female reproductive tract between female-specific molecules, sperm, and SFPs.

After insemination, females undergo numerous physiological and behavioral changes that primarily serve to facilitate the production of progeny. In mosquitoes, female post-mating changes include increases in the rates of egg development, oviposition, and female lifespan. Mating also reduces female sexual receptivity and alters gene expression in tissues of the female reproductive tract. Furthermore, females need to store the sperm they receive at mating in specialized organs of the reproductive tract. Post-mating changes are mediated by the receipt of SFPs (and not sperm), but also require gene products expressed from the female reproductive tract. Finally, environmental factors (e.g., temperature, larval nutrition, the microbiome) can influence adult fertility.

The goal of the Max Planck Tandem Group in Mosquito Reproductive Biology is to characterize precopulatory male-female behavioral interactions that lead to a successful copulation and to identify male- and female-specific genes required for fertility. We are further interested in understanding how environmental factors influence adult fertility of mosquito vectors. We study precopulatory male-female behavioral interactions in the New World malaria vectors Anopheles albimanus and An. darlingi, postcopulatory physiological processes in the dengue vector Aedes aegypti, and examine how environmental factors influence fertility in Ae. aegypti and Ae. albopictus, a secondary dengue vector. Finally, as both Ae. aegypti and Ae. albopictus are present in Medellín, we are also interested in understating the population ecology of these vector species in a tropical urban setting.