In this project, the researcher will investigate synergistic interactions between animal behavior and microbial metabolism during seasonal changes in temperature. Animals, including humans, rely on the dietary intake of essential chemical building blocks that they cannot synthesize. Polyunsaturated fatty acids (PUFAs) are a class of essential dietary lipids that are important for cell membrane structure at low temperatures and in the central nervous system. Cold temperature adaptation in poikilotherms (‘cold blooded’ animals that do not independently regulate their body temperature), and neurological function in animals more broadly, depends on an ability to forage for PUFA-enriched food sources. The project’s research will use fruit flies and their dietary fungi as a model system to understand how animal feeding strategies and microbial lipid biosynthesis have co-evolved to meet physiological needs. Through its research aims, the project will 1) identify molecular mechanisms underlying the physiology of a pair of organisms whose interactions are important in agriculture and biotechnology 2) elucidate general principles of animal-microbial interactions based on diet and 3) increase functional understanding of a key lipid class in animal physiology and behavior. Through its education aim, the project will promote participation in the biological sciences by students in underrepresented groups.
To goal of this project is to explore the mechanisms and consequences of microbial-animal lipid exchange using a combination of behavioral, genetic, and biochemical approaches in both Drosophila melanogaster and multiple yeast species. Polyunsaturated fatty acid (PUFA) biosynthetic genes have been lost in many fungal lineages, so flies must forage for specific yeast species to access these lipids. Yeast, in turn, are immobile and rely on attracting insects to colonize new environments. In preliminary work, the association between a natural fruit fly population and different yeast species has been found to be dependent on temperature and yeast PUFA metabolism. It has also been established that PUFA biosynthesis in a yeast-based laboratory diet dictates the activity of flies in the cold and other seasonally relevant behaviors. The project will first uncover the signaling pathways by which fatty acids dictate fly behavior in response to cold temperatures. It will then investigate how flies make foraging decisions to optimize their lipidome using olfaction-based communication that has co-evolved alongside yeast fermentation. Finally, the project will develop new experimental systems to dissect behavioral phenotypes and physiological functions dictated by PUFAs in specific tissue and cell types in the fly. In parallel, the project will support research through training programs that integrate concepts across animal physiology and biophysics. This project is jointly funded by the Behavioral System Cluster and the Integrative Ecological Physiology Program in the Division of Integrative Organismal Systems.
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.
