Mining for protein S-sulfenylation in Arabidopsis uncovers redox-sensitive sites

Proc Natl Acad Sci U S A. 2019 Oct 15;116(42):21256-21261. doi: 10.1073/pnas.1906768116. Epub 2019 Oct 2.


Hydrogen peroxide (H2O2) is an important messenger molecule for diverse cellular processes. H2O2 oxidizes proteinaceous cysteinyl thiols to sulfenic acid, also known as S-sulfenylation, thereby affecting the protein conformation and functionality. Although many proteins have been identified as S-sulfenylation targets in plants, site-specific mapping and quantification remain largely unexplored. By means of a peptide-centric chemoproteomics approach, we mapped 1,537 S-sulfenylated sites on more than 1,000 proteins in Arabidopsis thaliana cells. Proteins involved in RNA homeostasis and metabolism were identified as hotspots for S-sulfenylation. Moreover, S-sulfenylation frequently occurred on cysteines located at catalytic sites of enzymes or on cysteines involved in metal binding, hinting at a direct mode of action for redox regulation. Comparison of human and Arabidopsis S-sulfenylation datasets provided 155 conserved S-sulfenylated cysteines, including Cys181 of the Arabidopsis MITOGEN-ACTIVATED PROTEIN KINASE4 (AtMAPK4) that corresponds to Cys161 in the human MAPK1, which has been identified previously as being S-sulfenylated. We show that, by replacing Cys181 of recombinant AtMAPK4 by a redox-insensitive serine residue, the kinase activity decreased, indicating the importance of this noncatalytic cysteine for the kinase mechanism. Altogether, we quantitatively mapped the S-sulfenylated cysteines in Arabidopsis cells under H2O2 stress and thereby generated a comprehensive view on the S-sulfenylation landscape that will facilitate downstream plant redox studies.

Keywords: Arabidopsis; S-sulfenylation; chemoproteomics; posttranslational modification; redox regulation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / metabolism*
  • Catalytic Domain / physiology
  • Cysteine / metabolism
  • Humans
  • Hydrogen Peroxide / metabolism
  • Mitogen-Activated Protein Kinase 1 / metabolism
  • Oxidation-Reduction
  • Proteins / metabolism*
  • RNA / metabolism
  • Serine / metabolism
  • Signal Transduction / physiology
  • Sulfenic Acids / metabolism
  • Sulfhydryl Compounds / metabolism*


  • Proteins
  • Sulfenic Acids
  • Sulfhydryl Compounds
  • Serine
  • RNA
  • Hydrogen Peroxide
  • Mitogen-Activated Protein Kinase 1
  • Cysteine