p62/SQSTM1-droplet serves as a platform for autophagosome formation and anti-oxidative stress response

Nat Commun. 2021 Jan 4;12(1):16. doi: 10.1038/s41467-020-20185-1.

Abstract

Autophagy contributes to the selective degradation of liquid droplets, including the P-Granule, Ape1-complex and p62/SQSTM1-body, although the molecular mechanisms and physiological relevance of selective degradation remain unclear. In this report, we describe the properties of endogenous p62-bodies, the effect of autophagosome biogenesis on these bodies, and the in vivo significance of their turnover. p62-bodies are low-liquidity gels containing ubiquitin and core autophagy-related proteins. Multiple autophagosomes form on the p62-gels, and the interaction of autophagosome-localizing Atg8-proteins with p62 directs autophagosome formation toward the p62-gel. Keap1 also reversibly translocates to the p62-gels in a p62-binding dependent fashion to activate the transcription factor Nrf2. Mice deficient for Atg8-interaction-dependent selective autophagy show that impaired turnover of p62-gels leads to Nrf2 hyperactivation in vivo. These results indicate that p62-gels are not simple substrates for autophagy but serve as platforms for both autophagosome formation and anti-oxidative stress.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis Regulatory Proteins / metabolism
  • Autophagosomes / metabolism*
  • Autophagosomes / ultrastructure
  • Autophagy
  • Cell Line
  • Gels
  • Hepatocytes / metabolism
  • Hepatocytes / ultrastructure
  • Humans
  • Kelch-Like ECH-Associated Protein 1 / metabolism
  • Liver / injuries
  • Liver / pathology
  • Mice
  • Mice, Inbred C57BL
  • Microtubule-Associated Proteins / metabolism
  • NF-E2-Related Factor 2 / metabolism
  • Oxidative Stress*
  • Protein Binding
  • Sequestosome-1 Protein / metabolism*
  • Unilamellar Liposomes

Substances

  • Apoptosis Regulatory Proteins
  • GABARAP protein, mouse
  • Gels
  • Kelch-Like ECH-Associated Protein 1
  • Map1lc3b protein, mouse
  • Microtubule-Associated Proteins
  • NF-E2-Related Factor 2
  • Sequestosome-1 Protein
  • Unilamellar Liposomes

Associated data

  • figshare/10.6084/m9.figshare.13218746