Role of mitochondria in apoptosis.

Apoptosis is characterized by biochemical processes that are largely conserved throughout evolution. The basic elements of the system comprise caspases, their activators and inhibitors, and regulators of mitochondrial integrity. New evidence reveals the role of mitochondria as the central coordinators of apoptosis. Accordingly, some caspases are sequestered within the mitochondria, and mitochondria contain additional proapoptotic factors. Bcl-2 and Bax homologs regulate the integrity of the mitochondrial outer membrane, which may also serve as a scaffold for the apoptotic machinery.