The long-term objectives are to devise pharmacologic interventions to modulate mitochondrial uncoupling functions to improve metabolic homeostasis and extend life span. We are interested in developing Drosophila melanogaster as a novel model system for investigating the mechanisms whereby modulated mitochondrial uncoupling influences energy storage/utilization, glucose homeostasis, insulin signaling and aging. Our preliminary results demonstrate that targeting of two independent mitochondrial uncoupling proteins, hUCP2 and mUCP1, to the Drosophila insulin-like peptides producing cells (IPCs) affects the level of insulin-like peptide message, glucose homeostasis and leads to life span extension. The goals for this proposal are to first perform proof-of-principal studies with techniques well practiced in our lab in order to more thoroughly define the metabolic characteristics of these transgenic flies. Second, we will extend our preliminary analysis on components of the insulin signaling pathway to attain a comprehensive view of how increased UCP expression in the IPCs might be influencing insulin signaling. Third, given the promising life extension phenotype observed in these flies, we will develop molecular genetic tools to allow temporal control of UCP expression in the IPCs. By segregating the effect of UCP expression in IPCs during adulthood during development we can begin to understand the systemic impact of increased UCP expression in the adult IPCs, not only in metabolic homeostasis but also the aging process. The R21 mechanism would afford us the necessary resources to perform the proposed studies and yield results critical for a comprehensive development of a novel Drosophila model to more fully understand the role of modulated mitochondrial uncoupling in insulin signaling and longevity. [unreadable] [unreadable] [unreadable] [unreadable]