Characterization of AMPK in female Aedes aegypti and Georgecraigius atropalpus mosquitoes in relation to low and adequate food intake

Abstract:

AMPK is a sensor of cellular fuel and energy status in mammals and Drosophila melanogaster. When activated, AMPK switches off anabolic pathways that consume ATP and switches on catabolic processes that produce ATP. We investigated the role of AMPK in regulating energy metabolism in autogenous Georgecraigius atropalpus (formerly Ochlerotatus atropalpus) and anautogenous Aedes aegypti L. (Stegomyia aegypti), mosquitoes that differ to varying degrees on larval and adult-derived nutrients for reproduction. We fed chemical activators of AMPK to mosquitoes to signal metabolic stress, and then measured macronutrients utilized in response and whether this response affected mosquito egg development. Our results demonstrate a role for AMPK in mosquito energy metabolism and we report that catabolic pathways affected by AMPK activation differ according to female nutritional condition and breeding strategy. Glycogen was the first source of energy utilized by well-nourished females in response to chronic AMPK activation. In malnourished females, the catabolic pathway activated depended on female breeding strategy. Lastly, we observed delayed follicle development in female Gc. atropalpus in which AMPK was chronically activated. Our results indicate that AMPK signaling of metabolic stress leads to a decrease in macronutrients that may affect mosquito reproduction. The AMPK regulatory pathway offers an attractive target for disruption as an approach for mosquito vector population control.

Keywords::

• 5′-AMP-activated protein kinase
• glycogen
• lipid
• energetics
• nutrient utilization
• metabolism
• oogenesis

Acknowledgments

This paper has greatly benefitted from comments by anonymous reviewers. The authors would like to thank John Frey and Ben Peterson for mosquito rearing and the School of Arts and Science for a summer fellowship to AA Qayum. Portions of this research were funded by NIH/NIAID grant (K22AI070644) to A Telang as well as by University of South Florida Sarasota-Manatee Arts and Science Dean’s funds to A Telang.

Disclosure

The authors report no conflicts of interest in this work.