Figure 2.

Mitochondrial quality control by mitochondrial dynamics and mitophagy. Mitochondrial health is maintained through the interaction between mitochondrial dynamics and mitophagy which is a selective separation of damaged mitochondria by autophagy. Stress induces mitochondrial fission, which divides stress-damaged mitochondria by healthy and damaged parts. Damaged mitochondria result in accumulation of PINK1, which phosphorylates Mfn2, in turn activating Parkin. Parkin then ubiquitinates Mfn2, and the Mfn2-Parkin interaction triggers mitophagy. P62 is recruited and binds the Parkin-ubiquitinated substrates, linking them to LC3. Mitochondria are then engulfed after elongation of the isolation membrane, referred to as the autophagosome. Mitophagy by the PINK1-Mfn2-Parkin signaling pathway is achieved by elimination of damaged mitochondria. P, phosphorylation; Ub, Ubiquitination.