Back to article: Mitochondrial stress management: a dynamic journey
FIGURE 4: The interplay between mitochondrial dynamics and mitophagy. The mitochondrial network shifts between continuous cycles of fusion and fission, each of which can last seconds to minutes. Fission of mitochondria (2) is carried out by the Drp1 GTPase, which is recruited to the OMM from the cytosol. Fission events often generate daughter units with different Δym: on the one hand, some mitochondria are depolarized, but the Δym can be restored (3) by fusion with other mitochondria (1). After solitary periods, mitochondria might also fuse if the membrane potential is above a certain threshold. On the other hand, sustained Δym depolarization triggers cleavage of Opa1, reduction in Mfn capacity and accumulation of PINK1/Parkin in the OMM (4). This targets single dysfunctional mitochondrion to mitophagy (5), where it is engulfed by the autophagosome. Image adapted from Twig G. and Shirihai O.S. (2011) [220].
220. Twig G, Shirihai OS (2011). The Interplay Between Mitochondrial Dynamics and Mitophagy. Antioxid Redox Signal 14(10): 1939-1951. http://dx.doi.org/10.1089/ars.2010.3779