What does BH3-only protein do?

The BH3-only proteins activate apoptosis by binding and neutralizing the pro-survival proteins, allowing Bax/Bak to homo-oligomerize and permeabilize the mitochondria.

What is the role of BH3?

The BH3 domain of BH3-only proteins is required for the ability of these proteins to bind BCL-2-like pro-survival proteins and to trigger apoptosis. BH3-only proteins are essential for the initiation of programmed cell death and stress-induced apoptosis in species as distantly related as nematodes and mice.

Is Puma a BH3-only protein?

Earlier studies of Puma have yielded equivocal results, with some concluding that it also acts as a direct activator and other studies suggesting that it acts solely as a sensitizer BH3-only protein.

What are anti-apoptotic proteins?

The main function of anti-apoptotic BCL-2 proteins is to restrain pro-apoptotic BAX/BAK, thus preserving mitochondrial outer membrane integrity. This is achieved by direct binding and sequestration of pro-apoptotic BH3-only proteins that possess the ability to directly or indirectly activate BAX/BAK.

What is the role of Bcl-2 in apoptosis?

BCL2 prevents BAX/BAK oligomerization, which would otherwise lead to the release of several apoptogenic molecules from the mitochondrion. It is also known that BCL2 binds to and inactivates BAX and other pro-apoptotic proteins, thereby inhibiting apoptosis.

Which of the following is an apoptotic protein?

Anti-apoptotic proteins BCL-2, MCL-1 and A1 summate collectively to maintain survival of immune cell populations both in vitro and in vivo.

Why BH3 does not exist but BH3 exist?

BH3 molecule is electron deficient in nature since the B atom has only 6 electrons around it so it exist in the form of dimer that is B2H6. BF3 is also electron deficient but because of larger size of F atom it cannot undergo dimerization.