LMS Ad hoc Seminar – William W. Ja
“Drosophila ABCs: Aging, Behavior, and ‘Crobes”
The Ja lab uses Drosophila as a model for dissecting genetic and neural mechanisms of aging, behavior, and disease. Here, we discuss some of our recent work on 1) how diet and temperature affect aging, 2) new tools for studying the dynamic interactions between sleep and feeding, and 3) the impact of the microbiota on fly physiology and development. (1) Aging. Dietary restriction (DR) and cold temperature prolong life in a variety of organisms ranging from invertebrates to mammals. Contrary to previous studies, we show that flies exposed to cold show metabolic changes reminiscent of DR, including reduced protein translation, enhanced mitochondrial efficiency, and upregulation of the translation initiation inhibitor, d4E-BP. d4E-BP levels also affect lifespan regulation by cold, suggesting that DR and temperature act via at least partially overlapping mechanisms. (2) Behavior. Sleep and feeding are closely regulated and, although many studies have examined their relationship, these two behaviors are typically assayed independently. We have recently developed the Activity Recording CAFE (ARC) that enables simultaneous measurements of feeding and motion from individual flies at high resolution, allowing us to identify mechanisms regulating homeostatic and postprandial sleep. (3) Microbe interactions. Fly-associated microbes can promote host development or extend fly lifespan. Our recent results show that microbial quantity, rather than quality or composition, plays an important role on fly physiology and lifespan during undernutrition.