Cytochrome c is a crucial player in the intrinsic pathway. Once released from the mitochondria, it binds to apoptotic protease activating factor-1 (Apaf-1) in the cytosol, leading to the formation of the apoptosome. This complex recruits and activates caspase-9, which in turn activates downstream executioner caspases like caspase-3 and caspase-7, culminating in apoptosis. The release of cytochrome c is a point of no return in the apoptotic process, emphasizing its importance in the regulation of cell death.
