Biological process

GO:0008629

intrinsic apoptotic pathway, intrinsic apoptotic signalling pathway, mitochondrial-mediated apoptotic pathway

The series of molecular signals in which an intracellular signal is conveyed to trigger the apoptotic death of a cell. The pathway starts with reception of an intracellular signal (e.g. DNA damage, endoplasmic reticulum stress, oxidative stress etc.), and ends when the execution phase of apoptosis is triggered. The intrinsic apoptotic signaling pathway is crucially regulated by permeabilization of the mitochondrial outer membrane (MOMP).

induction of apoptosis by intracellular signals

The signals that start intrinsic apoptosis may come from extracellular sources (e.g. oxidative stress, UV exposure), but the reception of the signal and thus the signaling pathway start inside the cell (as a result of DNA damage, redox imbalance, etc.). Examples are ZPR9 (ZNF622) and ASK1 (MAP3K5) (UniProt symbols Q969S3 and Q99683) in PMID:21771788. A diagram of the intrinsic apoptotic pathway including examples of molecular players can be found in Figure 2 in PMID:21760595.