Discovery of mosquito survival tactics leaves room for new disease vector control tactics

The appendages that protrude from a mosquito's head hold the sensory systems that account for nearly all of its ability to detect and respond to a wide range of chemical signals that are critical for its reproduction and survival. These systems rely on genes that are part of three families of chemosensory receptors. The genes include gustatory, ionotropic, and odorant receptors, which are all involved in a wide range of essential behaviors.

The lab of the professor of biological sciences used the techniques of gene editing to create mosquitoes that could map and functionally characterize the role of the chemosensory pathways.

While it is widely used in other model organisms, it remains technically demanding in Anopheles mosquitoes.

The Zwiebel lab had good reason to believe that Ir76b acts as a crucial co-receptor required to form active IR complexes on the mosquito head appendages. They collected data that supported the belief.

Female mosquitoes need the IR pathways for olfactory and probably gustatory responses to amines, which are a diverse family of chemical compounds that includes ammonia, an important component of human body odor that attracts biting mosquitoes.

The data shows the roles of Ir76b across olfactory and gustatory pathways, as well as a potential target for the design of new disease control strategies.

One exciting discovery we found is the unusual enhanced activities of mosquito antenna neuronal response to several amines, which are components of human sweat.

Malaria has persisted since the dawn of humanity. The global health crisis caused by these diseases is responsible for the deaths of more than half a million people each year. There is a chance to develop another approach to reducing mosquito-borne disease.

The data shows that the mosquito's behavior is complex and that it could be a new target for controlling mosquito transmission of diseases.

The study is in the National Academy of Sciences.

More information: Zi Ye et al, Discrete roles of Ir76b ionotropic coreceptor impact olfaction, blood feeding, and mating in the malaria vector mosquito Anopheles coluzzii, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2112385119 Journal information: Proceedings of the National Academy of Sciences