Dr. Capaldi's lab focuses on determining how budding yeast processes and integrates information from the environment to regulate cell growth. To tackle this problem they use a three-pronged approach. First, they use systems, genomic, proteomic, and traditional biochemical and cell biology methods to determine how known signaling pathways and proteins function and interact in different stress and starvation conditions. Second, they use high-throughput screens to identify new components of the cell growth control network. Third, they study key signaling events and proteins in detail using biochemical methods to add mechanistic detail to our network model.
These studies impact their understanding of cancer since many of the proteins involved in cell growth control are conserved across eukaryotes. For example, they recently discovered that a poorly studied class of second messengers are called as the Inositol Pyrophosphates (PP-IPs) act in parallel with the Target of Rapamycin Complex I (TORC1) pathway to control the activity of a Class I histone deacetylase and the expression of cell growth genes. These new data may explain why mutations in enzymes that synthesize the PP-IPs (Kcs1 and Vip1) lead to cancer. Going forward, they expect that collaboration with other members of the University of Arizona Cancer Center will help them to determine the impact that the PP-IPs and other proteins they discover play in human cells and cancer development.