FIP200 Phosphorylation Regulates Late Steps in Mitophagy

J Mol Biol. 2024 Aug 1;436(15):168631. doi: 10.1016/j.jmb.2024.168631. Epub 2024 May 29.

Abstract

Mitophagy is a specific type of autophagy responsible for the selective elimination of dysfunctional or superfluous mitochondria, ensuring the maintenance of mitochondrial quality control. The initiation of mitophagy is coordinated by the ULK1 kinase complex, which engages mitophagy receptors via its FIP200 subunit. Whether FIP200 performs additional functions in the subsequent later phases of mitophagy beyond this initial step and how its regulation occurs, remains unclear. Our findings reveal that multiple phosphorylation events on FIP200 differentially control the early and late stages of mitophagy. Furthermore, these phosphorylation events influence FIP200's interaction with ATG16L1. In summary, our results highlight the necessity for precise and dynamic regulation of FIP200, underscoring its importance in the progression of mitophagy.

Keywords: ATG16L1; Atg1/ULK1 kinase complex; FIP200; autophagy; mitophagy.

MeSH terms

  • Autophagy-Related Protein-1 Homolog / genetics
  • Autophagy-Related Protein-1 Homolog / metabolism
  • Autophagy-Related Proteins* / genetics
  • Autophagy-Related Proteins* / metabolism
  • Carrier Proteins / metabolism
  • HeLa Cells
  • Humans
  • Mitochondria* / metabolism
  • Mitophagy*
  • Phosphorylation
  • mRNA Cleavage and Polyadenylation Factors / genetics
  • mRNA Cleavage and Polyadenylation Factors / metabolism

Substances

  • Autophagy-Related Proteins
  • RB1CC1 protein, human
  • ATG16L1 protein, human
  • Autophagy-Related Protein-1 Homolog
  • mRNA Cleavage and Polyadenylation Factors
  • Carrier Proteins