Involved in the activation cascade of caspases responsible for apoptosis execution. Recruited to both Fas- and TNFR-1 receptors in a FADD dependent manner. May participate in the granzyme B apoptotic pathways. Cleaves and activates effector caspases CASP3, CASP4, CASP6, CASP7, CASP8 and CASP9. Hydrolyzes the small- molecule substrates, Tyr-Val-Ala-Asp-; -AMC and Asp-Glu-Val-Asp-; -AMC. ; Isoform 7 can enhance NF-kappaB activity but promotes only slight apoptosis. ; Isoform C is proteolytically inactive.
