During apoptosis, cytochrome c is released from the mitochondria into the cytoplasm. This release is often triggered by pro-apoptotic signals that cause mitochondrial outer membrane permeabilization (MOMP). Once in the cytoplasm, cytochrome c binds to Apaf-1 (apoptotic protease activating factor-1), forming the apoptosome. This complex then activates initiator caspase-9, which in turn activates executioner caspases like caspase-3 and caspase-7, leading to cell death.
