What is the Role of Caspases in the Extrinsic Pathway?

Caspases are central to the execution of apoptosis. In the extrinsic pathway, the activation of caspase-8 is a pivotal step. Once activated within the DISC, caspase-8 can directly cleave and activate downstream executioner caspases such as caspase-3 and caspase-7. This leads to the cleavage of cellular substrates, the dismantling of cellular structures, and ultimately cell death. Additionally, in certain contexts, activated caspase-8 can also engage the intrinsic apoptotic pathway by cleaving Bid, a pro-apoptotic Bcl-2 family protein, thereby linking the two pathways.