Indicate whether each of the following mutations would likely promote (P) or inhibit (I) apoptosis in cells harboring the mutation(s). Your answer would be a four-letter string composed of letters P and I only, e.g. PPPI.
( ) Mutations in the pro-apoptotic effector Bcl2 family proteins Bax and Bak that prevent their association with the outer mitochondrial membrane.
( ) A mutation in the BIR domain of the IAP protein DIAP1 that prevents binding to either caspases or anti-IAP proteins.
( ) A mutation in the anti-IAP protein Reaper that prevents its binding to the IAP proteins.
( ) A mutation in the CARD domain of caspase-9 that prevents its binding to Apaf1.

Question

Indicate whether each of the following mutations would likely promote (P) or inhibit (I) apoptosis in cells harboring the mutation(s). Your answer would be a four-letter string composed of letters P and I only, e.g. PPPI.
( )	Mutations in the pro-apoptotic effector Bcl2 family proteins Bax and Bak that prevent their association with the outer mitochondrial membrane.
( )	A mutation in the BIR domain of the IAP protein DIAP1 that prevents binding to either caspases or anti-IAP proteins.
( )	A mutation in the anti-IAP protein Reaper that prevents its binding to the IAP proteins.
( )	A mutation in the CARD domain of caspase-9 that prevents its binding to Apaf1.

Quizplus · Accepted Answer

Association of Bax and Bak with the mitochondrial membrane is necessary (although not sufficient) for the activation of the intrinsic pathway of apoptosis. The same is true for the association of procaspase-9 with Apaf1 in apoptosomes. Interfering with the binding of IAPs to the caspases promotes apoptosis, while interfering with the binding of IAPs to anti-IAPs represses apoptosis.

Indicate Whether Each of the Following Mutations Would Likely Promote