Cytoplasmic DAXX drives SQSTM1/p62 phase condensation to activate Nrf2-mediated stress response

Nat Commun. 2019 Aug 21;10(1):3759. doi: 10.1038/s41467-019-11671-2.

Abstract

Autophagy cargo recognition and clearance are essential for intracellular protein quality control. SQSTM1/p62 sequesters intracellular aberrant proteins and mediates cargo delivery for their selective autophagic degradation. The formation of p62 non-membrane-bound liquid compartments is critical for its function as a cargo receptor. The regulation of p62 phase separation/condensation has yet been poorly characterised. Using an unbiased yeast two-hybrid screening and complementary approaches, we found that DAXX physically interacts with p62. Cytoplasmic DAXX promotes p62 puncta formation. We further elucidate that DAXX drives p62 liquid phase condensation by inducing p62 oligomerisation. This effect promotes p62 recruitment of Keap1 and subsequent Nrf2-mediated stress response. The present study suggests a mechanism of p62 phase condensation by a protein interaction, and indicates that DAXX regulates redox homoeostasis, providing a mechanistic insight into the prosurvival function of DAXX.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics
  • Adaptor Proteins, Signal Transducing / metabolism*
  • Animals
  • Autophagy / physiology
  • Cell Line
  • Co-Repressor Proteins
  • Cytoplasm / metabolism*
  • Drosophila
  • Female
  • Gene Knockdown Techniques
  • HEK293 Cells
  • HeLa Cells
  • Humans
  • Kelch-Like ECH-Associated Protein 1 / metabolism
  • Male
  • Mice
  • Molecular Chaperones
  • NF-E2-Related Factor 2 / metabolism*
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Protein Binding
  • Protein Folding
  • Protein Interaction Domains and Motifs
  • RNA-Binding Proteins / metabolism*
  • Sequestosome-1 Protein / metabolism*

Substances

  • Adaptor Proteins, Signal Transducing
  • Co-Repressor Proteins
  • DAXX protein, human
  • KEAP1 protein, human
  • Kelch-Like ECH-Associated Protein 1
  • Molecular Chaperones
  • NF-E2-Related Factor 2
  • NFE2L2 protein, human
  • Nuclear Proteins
  • P62 protein, human
  • RNA-Binding Proteins
  • SQSTM1 protein, human
  • Sequestosome-1 Protein