The cytochrome c oxidase biogenesis factor AtCOX17 modulates stress responses in Arabidopsis

Plant Cell Environ. 2016 Mar;39(3):628-44. doi: 10.1111/pce.12647. Epub 2015 Dec 21.


COX17 is a soluble protein from the mitochondrial intermembrane space that participates in the transfer of copper for cytochrome c oxidase (COX) assembly in eukaryotic organisms. In this work, we studied the function of both Arabidopsis thaliana AtCOX17 genes using plants with altered expression levels of these genes. Silencing of AtCOX17-1 in a cox17-2 knockout background generates plants with smaller rosettes and decreased expression of genes involved in the response of plants to different stress conditions, including several genes that are induced by mitochondrial dysfunctions. Silencing of either of the AtCOX17 genes does not affect plant development or COX activity but causes a decrease in the response of genes to salt stress. In addition, these plants contain higher reactive oxygen and lipid peroxidation levels after irrigation with high NaCl concentrations and are less sensitive to abscisic acid. In agreement with a role of AtCOX17 in stress and abscisic acid responses, both AtCOX17 genes are induced by several stress conditions, abscisic acid and mutation of the transcription factor ABI4. The results indicate that AtCOX17 is required for optimal expression of a group of stress-responsive genes, probably as a component of signalling pathways that link stress conditions to gene expression responses.

Keywords: abscisic acid; mitochondrion; salt stress.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological / drug effects
  • Arabidopsis / enzymology*
  • Arabidopsis / genetics
  • Arabidopsis / physiology*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Cation Transport Proteins / genetics
  • Cation Transport Proteins / metabolism*
  • Cluster Analysis
  • Copper Transport Proteins
  • Electron Transport Complex IV / metabolism*
  • Gene Expression Regulation, Plant / drug effects
  • Gene Silencing / drug effects
  • Genes, Plant
  • Mitochondria / drug effects
  • Mitochondria / metabolism
  • Oxidative Stress / drug effects
  • Oxidative Stress / genetics
  • Plant Development / drug effects
  • Plant Development / genetics
  • Plants, Genetically Modified
  • Protein Transport / drug effects
  • Sodium Chloride / pharmacology
  • Stress, Physiological* / drug effects
  • Stress, Physiological* / genetics
  • Transcription Factors / metabolism


  • ABI4 protein, Arabidopsis
  • Arabidopsis Proteins
  • AtCOX17 protein, Arabidopsis
  • Cation Transport Proteins
  • Copper Transport Proteins
  • Transcription Factors
  • Sodium Chloride
  • Electron Transport Complex IV