Singlet Oxygen-Induced Cell Death in Arabidopsis under High-Light Stress Is Controlled by OXI1 Kinase

Plant Physiol. 2016 Mar;170(3):1757-71. doi: 10.1104/pp.15.01546. Epub 2016 Jan 8.

Abstract

Studies of the singlet oxygen ((1)O2)-overproducing flu and chlorina1 (ch1) mutants of Arabidopsis (Arabidopsis thaliana) have shown that (1)O2-induced changes in gene expression can lead to either programmed cell death (PCD) or acclimation. A transcriptomic analysis of the ch1 mutant has allowed the identification of genes whose expression is specifically affected by each phenomenon. One such gene is OXIDATIVE SIGNAL INDUCIBLE1 (OXI1) encoding an AGC kinase that was noticeably induced by excess light energy and (1)O2 stress conditions leading to cell death. Photo-induced oxidative damage and cell death were drastically reduced in the OXI1 null mutant (oxi1) and in the double mutant ch1*oxi1 compared with the wild type and the ch1 single mutant, respectively. This occurred without any changes in the production rate of (1)O2 but was cancelled by exogenous applications of the phytohormone jasmonate. OXI1-mediated (1)O2 signaling appeared to operate through a different pathway from the previously characterized OXI1-dependent response to pathogens and H2O2 and was found to be independent of the EXECUTER proteins. In high-light-stressed plants, the oxi1 mutation was associated with reduced jasmonate levels and with the up-regulation of genes encoding negative regulators of jasmonate signaling and PCD. Our results show that OXI1 is a new regulator of (1)O2-induced PCD, likely acting upstream of jasmonate.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / genetics*
  • Arabidopsis / genetics*
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics*
  • Arabidopsis Proteins / metabolism
  • Cyclopentanes / pharmacology
  • Gene Expression Profiling / methods
  • Gene Expression Regulation, Plant / drug effects
  • Gene Expression Regulation, Plant / genetics*
  • Gene Expression Regulation, Plant / radiation effects
  • Light
  • Models, Genetic
  • Mutation
  • Oligonucleotide Array Sequence Analysis
  • Oxylipins / pharmacology
  • Photosystem II Protein Complex / genetics
  • Photosystem II Protein Complex / metabolism
  • Plant Growth Regulators / pharmacology
  • Protein-Serine-Threonine Kinases / genetics*
  • Protein-Serine-Threonine Kinases / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Signal Transduction / drug effects
  • Signal Transduction / genetics
  • Signal Transduction / radiation effects
  • Singlet Oxygen / metabolism*

Substances

  • Arabidopsis Proteins
  • Cyclopentanes
  • Oxylipins
  • Photosystem II Protein Complex
  • Plant Growth Regulators
  • Singlet Oxygen
  • jasmonic acid
  • OXI1 protein, Arabidopsis
  • Protein-Serine-Threonine Kinases