Dynamic Arginine Methylation of Tumor Necrosis Factor (TNF) Receptor-associated Factor 6 Regulates Toll-like Receptor Signaling

J Biol Chem. 2015 Sep 4;290(36):22236-49. doi: 10.1074/jbc.M115.653543. Epub 2015 Jul 28.

Abstract

Arginine methylation is a common post-translational modification, but its role in regulating protein function is poorly understood. This study demonstrates that, TNF receptor-associated factor 6 (TRAF6), an E3 ubiquitin ligase involved in innate immune signaling, is regulated by reversible arginine methylation in a range of primary and cultured cells. Under basal conditions, TRAF6 is methylated by the methyltransferase PRMT1, and this inhibits its ubiquitin ligase activity, reducing activation of toll-like receptor signaling. In response to toll-like receptor ligands, TRAF6 is demethylated by the Jumonji domain protein JMJD6. Demethylation is required for maximal activation of NF-κB. Loss of JMJD6 leads to reduced response, and loss of PRMT1 leads to basal pathway activation with subsequent desensitization to ligands. In human primary cells, variations in the PRMT1/JMJD6 ratio significantly correlate with TRAF6 methylation, basal activation of NF-κB, and magnitude of response to LPS. Reversible arginine methylation of TRAF6 by the opposing effects of PRMT1 and JMJD6 is, therefore, a novel mechanism for regulation of innate immune pathways.

Keywords: Jumonji domain-containing protein 6; TNF receptor associated factor (TRAF); arginine methylation; endotoxin; hepatocyte; innate immunity; macrophage; post-translational modification; protein arginine methyltransferase; toll-like receptor (TLR).

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arginine / metabolism*
  • Blotting, Western
  • Cell Line
  • Cell Line, Tumor
  • Cells, Cultured
  • Humans
  • Interleukin-1 Receptor-Associated Kinases / genetics
  • Interleukin-1 Receptor-Associated Kinases / metabolism
  • Jumonji Domain-Containing Histone Demethylases / genetics
  • Jumonji Domain-Containing Histone Demethylases / metabolism
  • Kinetics
  • Ligands
  • Male
  • Methylation
  • Mice, Inbred C57BL
  • NF-kappa B / genetics
  • NF-kappa B / metabolism
  • Protein-Arginine N-Methyltransferases / genetics
  • Protein-Arginine N-Methyltransferases / metabolism
  • RNA Interference
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism
  • Signal Transduction*
  • TNF Receptor-Associated Factor 6 / genetics
  • TNF Receptor-Associated Factor 6 / metabolism*
  • Toll-Like Receptors / metabolism*
  • Ubiquitin-Protein Ligases / genetics
  • Ubiquitin-Protein Ligases / metabolism

Substances

  • Ligands
  • NF-kappa B
  • Repressor Proteins
  • TNF Receptor-Associated Factor 6
  • Toll-Like Receptors
  • Arginine
  • JMJD6 protein, human
  • Jumonji Domain-Containing Histone Demethylases
  • PRMT1 protein, human
  • Protein-Arginine N-Methyltransferases
  • Ubiquitin-Protein Ligases
  • IRAK3 protein, human
  • Interleukin-1 Receptor-Associated Kinases