Comparative analysis of the reactive oxygen species-producing enzymatic activity of Arabidopsis NADPH oxidases

Plant J. 2019 Apr;98(2):291-300. doi: 10.1111/tpj.14212. Epub 2019 Feb 14.


Reactive oxygen species (ROS) produced by NADPH oxidases, called respiratory burst oxidase homologs (Rbohs), play crucial roles in development as well as biotic and abiotic stress responses in plants. Arabidopsis has 10 Rboh genes, AtRbohA to AtRbohJ. Five AtRbohs (AtRbohC, -D, -F, -H and -J) are synergistically activated by Ca2+ -binding and protein phosphorylation to produce ROS that play various roles in planta, although the activities of the other Rbohs remain unknown. With a heterologous expression system, we found a range of ROS-producing activity among the AtRbohs with differences up to 100 times, indicating that the required amounts of ROS are different in each situation where AtRbohs act. To specify the functions of AtRbohs involved in cell growth, we focused on AtRbohC, -H and -J, which are involved in tip growth of root hairs or pollen tubes. Ectopic expression of the root hair factor AtRbohC/ROOT HAIR DEFECTIVE 2 (RHD2) in pollen tubes restored the atrbohH atrbohJ defects in tip growth of pollen tubes. However, expression of AtRbohH or -J in root hairs did not complement the tip growth defect in the atrbohC/rhd2 mutant. Our data indicate that Rbohs possess different ranges of enzymatic activity, and that some Rbohs have evolved to carry specific functions in cell growth.

Keywords: Arabidopsis thaliana; Ca2+; phosphorylation; reactive oxygen species (ROS); respiratory burst oxidase homolog (Rboh).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / enzymology*
  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism
  • HEK293 Cells
  • Humans
  • Mutation
  • NADPH Oxidases / classification
  • NADPH Oxidases / genetics
  • NADPH Oxidases / metabolism*
  • Phosphorylation
  • Plant Roots / growth & development
  • Pollen Tube / growth & development
  • Reactive Oxygen Species / metabolism*


  • Arabidopsis Proteins
  • Reactive Oxygen Species
  • Rhd2 protein, Arabidopsis
  • respiratory burst oxidase homolog D, Arabidopsis
  • NADPH Oxidases
  • RBOHH protein, Arabidopsis
  • RBOHJ protein, Arabidopsis
  • superoxide-forming enzyme