Thomas Neufeld

,

Credentials

PhD

Research Summary

The Neufeld lab is interested in the basic mechanisms of cell growth control. They use the fruit fly Drosophila as a model system to investigate signaling pathways and cellular functions that regulate growth. The goal of their research is to understand how signals that control cell growth, such as nutrient conditions and growth factors, are connected to growth-promoting cellular processes such as nutrient uptake and biosynthesis. They focus on the target of rapamycin (TOR) protein kinases, which are central regulators of cell growth whose function is conserved from yeast to plants to mammals. TOR activity is controlled by nutrient levels, cellular energy state, and growth factors such as insulin, and in turn TOR controls multiple cellular functions critical for growth. Inappropriate activation of TOR signaling underlies a number of growth-related genetic diseases including cancer. In the lab, the approach is to identify mutations in genes involved in TOR signaling, and to characterize their function using multiple cellular and genetic assays.A second, related area of the lab's research centers on the degradative process known as autophagy. This process, which is controlled by the TOR pathway and induced by starvation, involves the non-selective engulfment and degradation of cytoplasm within the lysosome. Through autophagy, macromolecules and entire organelles are recycled into amino acids, lipids, and other simple molecules, thus supplying the cell with an internal source of nutrients under starvation conditions. Although autophagy has been understood morphologically for many years, the past decade has seen a new surge of interest in autophagy due to the recent discovery of approximately 20 "ATG" genes that regulate autophagy, and to the discovery that defects in autophagy are involved in aging, neurodegeneration, and cancer. The lab hopes to use the genetic tools available in Drosophila to define the functions and regulation of autophagy.