During the execution phase of apoptosis, which caspase is the principal 'executioner' caspase that cleaves cellular substrates including ICAD, lamins, and cytoskeletal proteins?
- A Caspase-8
- B Caspase-3 ✓
- C Caspase-9
- D Caspase-12
Correct answer: B. Caspase-3
Explanation
Caspase-3 is the principal executioner caspase in apoptosis, activated by either initiator caspase-8 (extrinsic pathway) or caspase-9 (intrinsic pathway). It cleaves ICAD releasing CAD endonuclease, lamins causing nuclear collapse, and cytoskeletal proteins. Caspase-12 is associated with ER stress-induced apoptosis, not the canonical execution phase. Caspase-8 and caspase-9 are initiator caspases.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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