Ca2+ is a signaling molecule that carries information in virtually all processes important to cell life, as well as participating in cell death. My laboratory focuses on the structure-function of proteins involved in either Ca2+ homeostasis or regulating mitochondrial function in cell life and death. Understanding the biological processes regulated by Ca2+ requires identification of the proteins involved and their control mechanisms. A second major focus addresses mitochondria, the "power house" of the cell that also plays a key role in programmed cell death - apoptosis. In apoptosis, the mitochondrial protein VDAC, regulating cellular energy metabolism, serves as a site for apoptotic signaling. Since VDAC functions at a checkpoint of cell life and death and because apoptosis is rendered ineffective in cancer cells, selective induction of VDAC-mediated apoptosis in carcinogenic tissues represents a potential cancer therapy.