Noncaspase proteases in apoptosis

Biochemical and genetic analysis of apoptosis has determined that intracell ular proteases are key effecters of cell death pathways. In particular, ear ly studies have pointed to the primacy of caspase proteases as mediators of execution. More recently, however, evidence has accumulated that noncaspas es, including cathepsins, calpains, granzymes, and the proteasome complex, also have roles in mediating and promoting cell death. An important goal is to understand the importance of distinct noncaspases in various forms of a poptosis, and to determine whether pathways mediated by noncaspase protease s intersect with those mediated by caspases. In this review the roles of no ncaspase proteases in the biochemistry of apoptosis will be discussed.