Caspase-7

Caspases are key effectors of programmed cell death. Caspase-7 along with caspase 3 and 6 form the group of effector caspases that are responsible for the cleavage of multiple substrates including the cytokeratins, PARP, alpha fodrin, NuMA and others. Caspase-7 is a 303 amino acid protein with high similarity to caspase-3. Caspase-7 occurs in three varient forms. Granzyme B activates pro-caspase-7 to a form which can cleave poly(ADP-ribose) polymerase (PARP) to its signature fragment of ~85 kDa. Also, in vivo caspase-7 appears to be a better substrate for granzyme B than caspase-3. Pro-caspase-7 has been shown to exist as dimers or high order oligomers. Caspase-7 may be an important intracellular effector of granzyme B-mediated apoptosis and cytotoxic T-lymophocyte-induced cell killing in vivo.