Which member of the BCL-2 protein family functions as an ANTI-apoptotic regulator that sequesters BH3-only proteins and prevents mitochondrial outer membrane permeabilization?
- A BAD
- B BIM
- C MCL-1 ✓
- D BAK
Correct answer: C. MCL-1
Explanation
MCL-1, like BCL-2, BCL-XL and BCL-W, contains BH domains that allow it to bind and neutralize pro-apoptotic members, maintaining mitochondrial integrity. BAD, BIM, BID, PUMA and NOXA are BH3-only pro-apoptotic sensors that either activate BAX/BAK or antagonize the anti-apoptotics. BAK is a multidomain effector that, with BAX, forms the pores releasing cytochrome c. Distinguishing these subfamilies is frequently tested.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.