apoptosome

Pronunciation: ă-pop′tō-sōm

Definition: A heptameric apoptotic protease activating factor 1 (Apaf-1)–cytochrome-c complex. The apoptosome recruits and activates caspases that cleave intracellular substrates and ultimately lead to cell death by apoptosis. Release of mitochondrial cytochrome-c into the cytoplasm results in binding with monomers of Apaf-1, thereby inducing a conformational change that permits a stable association with (deoxy)adenosine triphosphate and formation of the heptameric complex.

[apoptosis + -some]

See Also: apoptosis

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