FUNCTION: SwissProt: P55211 # Isoform 2 lacks activity is an dominant-negative inhibitor of caspase-9.
SIZE: 416 amino acids; 46281 Da
SUBUNIT: Heterotetramer that consists of two anti-parallel arranged heterodimers, each one formed by a 35 kDa (p35) and a 10 kDa (p10) subunit. Caspase-9 and APAF1 bind to each other via their respective NH2-terminal CED-3 homologous domains in the presence of cytochrome C and ATP. Interacts with the inhibitors BIRC2, BIRC4, BIRC5 and BIRC7.
TISSUE SPECIFICITY: Ubiquitous, with highest expression in the heart, moderate expression in liver, skeletal muscle, and pancreas. Low levels in all other tissues.
PTM: Cleavages at Asp-315 by granzyme B and at Asp-330 by caspase- 3 generate the two active subunits. Caspase-8 and -10 can also be involved in these processing events.
SIMILARITY: SwissProt: P55211 ## Belongs to the peptidase C14 family. & Contains 1 CARD domain.