FIGURE 17.

Tentative model of regulation of the mitochondrial quality control by Δψ. Parkin is an E3 ubiquitin ligase located in the cytosol, while PINK1 is a mitochondrial kinase carrying mitochondrial import sequence to be accumulated inside of mitochondria followed by degradation by PARL. Δψ drives PINK1 into mitochondria where it is processed by mitochondrial processing protease (MMP). When mitochondrial membrane potential is dissipated, PINK1 accumulates on the outer mitochondrial membrane, where it can recruit Parkin to impaired mitochondria followed by its ubiquitination as a starting point for mitophagy. OM, outer membrane; IM, inner membrane. TOM and TIM are transport outer and inner membrane proteins correspondingly. (From Ref. 210: Copyright 2010 Jin et al. Originally published in Journal of Cell Biology. 191: 933–942. doi:10.1083/jcb.201008084.)