Fig. 5.
From: PINK1 import regulation; a fine system to convey mitochondrial stress to the cytosol
High molecular weight (HMW) complex formation of PINK1. PINK1 forms a high molecular weight (HMW) complex with the TOM complex on the OMM in response to ΔΨm loss. Tom7, an accessory subunit of the TOM complex, may be involved in the lateral release of PINK1 into the OMM. The TOM complex is considered to provide a location for the activation of PINK1 kinase activity by facilitating the correct orientation of dimeric PINK1 to allow auto-phosphorylation in trans. At the same time, HMW complex formation with the TOM complex may allow rapid PINK1 re-import when mitochondria are repolarized to halt mitophagy