is an initiator caspase
The aspartic acid specific protease caspase-9 has been linked to the mitochondrial death pathway. It is activated during programmed cell death (apoptosis). Induction of stress signalling pathways JNK/SAPK causes release of cytochrome c from mitochondria and activation of apaf-1 (apoptosome), which in turn cleaves the pro-enzyme of caspase-9 into the active form.
Once intiated caspase-9 goes on to cleave procaspase-3 & procaspase-7 and which cleave several cellular targets, including poly ADP ribose polymerase.
- Lei K, Nimnual A, Zong W, Kennedy N, Flavell R, Thompson C, Bar-Sagi D, Davis R (2002). "The Bax subfamily of Bcl2-related proteins is essential for apoptotic signal transduction by c-Jun NH(2)-terminal kinase.". Mol Cell Biol 22 (13): 4929–42.
- Earnshaw W, Martins L, Kaufmann S "Mammalian caspases: structure, activation, substrates, and functions during apoptosis.". Annu Rev Biochem 68 383–424.