Light-Induced Acclimation of the Arabidopsis chlorina1 Mutant to Singlet Oxygen

• Published in: The Plant cell Vol. 25; no. 4; pp. 1445 - 1462
• Main Authors: Ramel, Fanny, Ksas, Brigitte, Akkari, Elsy, Mialoundama, Alexis S., Monnet, Fabien, Krieger-Liszkay, Anja, Ravanat, Jean-Luc, Mueller, Martin J., Bouvier, Florence, Havaux, Michel
• Format: Journal Article
• Language: English
• Published: England American Society of Plant Biologists 01-04-2013; American Society of Plant Biologists (ASPB)
• Subjects: Acclimatization; Acclimatization - genetics; Acclimatization - radiation effects; Acetates - pharmacology; Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Biochemistry, Molecular Biology; Biosynthetic Pathways - drug effects; Biosynthetic Pathways - genetics; Biosynthetic Pathways - radiation effects; Cell death; Cellular Biology; Chlorophyll - metabolism; Chlorophylls; Cyclopentanes - metabolism; Cyclopentanes - pharmacology; Gene Expression Regulation, Plant - drug effects; Gene Expression Regulation, Plant - radiation effects; Genes; Leaves; Life Sciences; Light; Lipid Peroxidation - radiation effects; Lipids; Molecular biology; Mutation; Oligonucleotide Array Sequence Analysis; Oxidation-Reduction - radiation effects; Oxidative stress; Oxygenases - genetics; Oxygenases - metabolism; Oxylipins - metabolism; Oxylipins - pharmacology; Photosystem II Protein Complex - genetics; Photosystem II Protein Complex - metabolism; Plant cells; Plant Growth Regulators - pharmacology; Plant Leaves - genetics; Plant Leaves - metabolism; Plants; Reactive Oxygen Species - metabolism; Reverse Transcriptase Polymerase Chain Reaction; Singlet oxygen; Singlet Oxygen - metabolism; Transcriptome - drug effects; Transcriptome - genetics; Transcriptome - radiation effects
• ISSN: 1040-4651; 1532-298X
• DOI: 10.1105/tpc.113.109827

Singlet oxygen ( 1 O 2 ) is a reactive oxygen species that can function as a stress signal in plant leaves leading to programmed cell death. In microalgae, 1 O 2 -induced transcriptomic changes result in acclimation to 1 O 2 . Here, using a chlorophyll b—less Arabidopsis thaliana mutant (chlorina1 [ch1]), we show that this phenomenon can also occur in vascular plants. The ch1 mutant is highly photosensitive due to a selective increase in the release of 1 O 2 by photosystem II. Under photooxidative stress conditions, the gene expression profile of ch1 mutant leaves very much resembled the gene responses to 1 O 2 reported in the Arabidopsis mutant flu. Preexposure of ch1 plants to moderately elevated light intensities eliminated photooxidative damage without suppressing 1 O 2 formation, indicating acclimation to 1 O 2 . Substantial differences in gene expression were observed between acclimation and high-light stress: A number of transcription factors were selectively induced by acclimation, and contrasting effects were observed for the jasmonate pathway. Jasmonate biosynthesis was strongly induced in ch1 mutant plants under high-light stress and was noticeably repressed under acclimation conditions, suggesting the involvement of this hormone in 1 O 2 -induced cell death. This was confirmed by the decreased tolerance to photooxidative damage of jasmonate-treated ch1 plants and by the increased tolerance of the jasmonate-deficient mutant delayed-dehiscence2.