Figure 6. Schematic of Ubl and Ub binding and phosphorylation by PINK1.

PINK1 accumulates on the mitochondria upon mitochondrial damage and autophosphorylates in trans on S228. The phosphorylation results in the creation of binding site for Ub and Parkin Ubl, which are then phosphorylated by PINK1 resulting in Parkin activation and initiation of mitophagy.