What Molecular Pathways are Involved in Apoptosis Regulation?

Apoptosis is controlled by a complex network of signaling pathways. The intrinsic (mitochondrial) pathway is primarily regulated by the Bcl-2 family of proteins, which includes both pro-apoptotic and anti-apoptotic members. The extrinsic pathway is mediated by death receptors on the cell surface, such as Fas and tumor necrosis factor receptor (TNFR). Both pathways converge on the activation of caspases, which are proteases that execute apoptosis by cleaving specific cellular substrates. Dysregulation at any point in these pathways can lead to insufficient apoptosis.