Mitochondrial fragmentation in apoptosis.
Mitochondrial outer membrane permeabilization (MOMP) is associated with most pro-apoptotic stimuli. MOMP results in the release of cytochrome c from the mitochondria into the cytosol, triggering caspase activation and subsequent apoptosis. Several theories explaining the mechanisms of MOMP have been proposed, one of which suggests that MOMP relies on the activation of the molecular machinery involved in fission, resulting in mitochondrial fragmentation. By contrast, several recent studies suggest that mitochondrial fragmentation occurs following MOMP. Moreover, under some conditions. MOMP occurs without mitochondrial fragmentation and, in fact, fragmentation even inhibits MOMP. Here, I discuss the apparently conflicting data and conclude that mitochondrial fragmentation is probably not a prerequisite for MOMP and cytochrome c release.
Arnoult
Damien
D
Unité de Physiopathologie des Infections Lentivirales, Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris, cedex 15, France. damarn@pasteur.fr <damarn@pasteur.fr>
D000818:Animals; D017209:Apoptosis; D045304:Cytochromes c / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D006801:Humans; D008928:Mitochondria / Q000378:metabolism*; D051336:Mitochondrial Membranes / Q000378:metabolism*; D008954:Models, Biological; D013997:Time Factors; D014346:Trypanosoma brucei brucei / Q000378:metabolism; D050998:bcl-2 Homologous Antagonist-Killer Protein / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000378:metabolism
D050998:bcl-2 Homologous Antagonist-Killer Protein; D051028:bcl-2-Associated X Protein; D045304:Cytochromes c