Role of PINK1 binding to the TOM complex and alternate intracellular membranes in recruitment and activation of the E3 ligase Parkin

Dev Cell. 2012 Feb 14;22(2):320-33. doi: 10.1016/j.devcel.2011.12.014. Epub 2012 Jan 25.

Abstract

Mutations in the mitochondrial kinase PINK1 and the cytosolic E3 ligase Parkin can cause Parkinson's disease. Damaged mitochondria accumulate PINK1 on the outer membrane where, dependent on kinase activity, it recruits and activates Parkin to induce mitophagy, potentially maintaining organelle fidelity. How PINK1 recruits Parkin is unknown. We show that endogenous PINK1 forms a 700 kDa complex with the translocase of the outer membrane (TOM) selectively on depolarized mitochondria whereas PINK1 ectopically targeted to the outer membrane retains association with TOM on polarized mitochondria. Inducibly targeting PINK1 to peroxisomes or lysosomes, which lack a TOM complex, recruits Parkin and activates ubiquitin ligase activity on the respective organelles. Once there, Parkin induces organelle selective autophagy of peroxisomes but not lysosomes. We propose that the association of PINK1 with the TOM complex allows rapid reimport of PINK1 to rescue repolarized mitochondria from mitophagy, and discount mitochondrial-specific factors for Parkin translocation and activation.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Autophagy
  • Carrier Proteins / metabolism*
  • Cytosol / metabolism
  • HeLa Cells
  • Humans
  • Immunoenzyme Techniques
  • Intracellular Membranes / metabolism*
  • Mitochondria / metabolism*
  • Protein Binding
  • Protein Kinases / metabolism*
  • Protein Multimerization
  • Protein Transport
  • Ubiquitin-Protein Ligases / metabolism*

Substances

  • Carrier Proteins
  • TOM translocase
  • Ubiquitin-Protein Ligases
  • parkin protein
  • Protein Kinases
  • PTEN-induced putative kinase