Ascorbate peroxidase 1 plays a key role in the response of Arabidopsis thaliana to stress combination.

TitleAscorbate peroxidase 1 plays a key role in the response of Arabidopsis thaliana to stress combination.
Publication TypeJournal Article
Year of Publication2008
AuthorsKoussevitzky S, Suzuki N, Huntington S, Armijo L, Sha W, Cortes D, Shulaev V, Mittler R
JournalJ Biol Chem
Volume283
Issue49
Pagination34197-203
Date Published2008 Dec 05
ISSN0021-9258
KeywordsArabidopsis, Arabidopsis Proteins, Ascorbate Peroxidases, Chloroplast Proteins, Chromatography, Liquid, Cytosol, Droughts, Gene Expression Regulation, Plant, Hot Temperature, Hydrogen Peroxide, Mass Spectrometry, Models, Biological, Mutation, Peroxidases, Proteomics, RNA, Messenger, Time Factors, Water
Abstract

<p>Within their natural habitat plants are subjected to a combination of different abiotic stresses, each with the potential to exacerbate the damage caused by the others. One of the most devastating stress combinations for crop productivity, which frequently occurs in the field, is drought and heat stress. In this study we conducted proteomic and metabolic analysis of Arabidopsis thaliana plants subjected to a combination of drought and heat stress. We identified 45 different proteins that specifically accumulated in Arabidopsis in response to the stress combination. These included enzymes involved in reactive oxygen detoxification, malate metabolism, and the Calvin cycle. The accumulation of malic enzyme during the combined stress corresponded with enhanced malic enzyme activity, a decrease in malic acid, and lower amounts of oxaloacetate, suggesting that malate metabolism plays an important role in the response of Arabidopsis to the stress combination. Cytosolic ascorbate peroxidase 1 (APX1) protein and mRNA accumulated during the stress combination. When exposed to heat stress combined with drought, an APX1-deficient mutant (apx1) accumulated more hydrogen peroxide and was significantly more sensitive to the stress combination than wild type. In contrast, mutants deficient in thylakoid or stromal/mitochondrial APXs were not more sensitive to the stress combination than apx1 or wild type. Our findings suggest that cytosolic APX1 plays a key role in the acclimation of plants to a combination of drought and heat stress.</p>

DOI10.1074/jbc.M806337200
Alternate JournalJ. Biol. Chem.
PubMed ID18852264
PubMed Central IDPMC2590703
Grant ListP20 RR16464-05 / RR / NCRR NIH HHS / United States
RR-03-008 / RR / NCRR NIH HHS / United States