Which complex assembles in the cytosol during the intrinsic pathway of apoptosis and serves as the activation platform for the initiator caspase of this pathway?

• A Death-inducing signaling complex (DISC)
• B Apoptosome ✓
• C Inflammasome
• D Membrane attack complex

Explanation

After mitochondrial outer membrane permeabilization, cytochrome c leaks into the cytosol and binds Apaf-1. In the presence of dATP, multiple Apaf-1 molecules oligomerize into a wheel-like heptameric structure called the apoptosome, which recruits and activates procaspase-9, the initiator caspase of the intrinsic pathway. The DISC activates caspase-8 in the extrinsic pathway, the inflammasome activates caspase-1 in pyroptosis, and the MAC is a complement effector unrelated to apoptosis.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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