Fig. 1.

Schematic representation of regulatory processes mediating MOMP and mitochondrial dynamics under healthy or apoptotic conditions. a Activation model of Bax/Bak-mediated MOMP. Illustrated is the dynamic interplay of pro- and anti-apoptotic Bcl-2 proteins in controlling permeabilization of mitochondrial outer membrane (MOM). Due to a lower rate of retrotranslocation BAK is mostly MOM-bound. Besides Bcl-2 family proteins, VDACs also regulate Bax and Bak activity, likely with different outcomes. In the case of Bax, they serve as platform for its assembly on the surface of mitochondria and formation of Bax pores. b Mitochondrial dynamics imbalance during apoptosis. (Left; Healthy mitochondria) Mitochondrial fusion and fission proteins and their roles in changing mitochondrial morphology. (Right; mitochondria in apoptotic cells) Activation of Bax/Bak during apoptosis leads to an imbalance in mitochondrial dynamics towards fission and cristae remodeling