One of the wonders of nature is how a single cell can develop into a multicellular animal with the form and function characteristic of the species. Animal development is remarkably reproducible even when environmental conditions fluctuate, suggesting that fitness depends on mechanisms that buffer development from variation. The Baugh Lab at Duke University seeks to understand the physiological mechanisms that result in such developmental homeostasis. The lab investigates how nutrient availability governs post-embryonic development in the roundworm C. elegans. Worm larvae respond to starvation by arresting development and increasing resistance to environmental stress (eg, heat, freezing, oxidation, pathogens, high salt, UV radiation, low oxygen, etc). Arrested larvae can survive starvation several weeks, which is longer than the normal lifespan of fed worms, but they respond rapidly to feeding and resume development. Insulin-like signaling controls this remarkable physiological transformation between arrest and development. However, the genome encodes 40 insulin-like signals, raising questions about their specificity and functional dynamics, while the function of individual signals remains largely uncharacterized. A genetic approach will be used to identify the insulin-like signals and signaling centers that promote development in response to feeding. A molecular approach will be used to investigate the regulation of all 40 insulin-like genes and to determine the influence of feedback on signaling dynamics. Graduate and undergraduate students, including those from underrepresented backgrounds, will be trained to perform the experiments and taught to write about and present the findings. With completion of this work, specific details critical to understanding how developmental homeostasis is maintained in this well-characterized model system will be learned, impacting research on organismal biology and insulin-like signaling in a variety of other systems.
