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Compartment-specific investigations of antioxidants and hydrogen peroxide in leaves of Arabidopsis thaliana during dark-induced senescence

The aim of this study was to gain insight into the compartment-specific roles of ascorbate and glutathione in leaf senescence in Arabidopsis thaliana. The subcellular distribution of ascorbate, glutathione, and hydrogen peroxide (H(2)O(2)) was analyzed by transmission electron microscopy and correla...

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Autores principales: Luschin-Ebengreuth, Nora, Zechmann, Bernd
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Springer Berlin Heidelberg 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4859865/
https://www.ncbi.nlm.nih.gov/pubmed/27217598
http://dx.doi.org/10.1007/s11738-016-2150-6
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author Luschin-Ebengreuth, Nora
Zechmann, Bernd
author_facet Luschin-Ebengreuth, Nora
Zechmann, Bernd
author_sort Luschin-Ebengreuth, Nora
collection PubMed
description The aim of this study was to gain insight into the compartment-specific roles of ascorbate and glutathione in leaf senescence in Arabidopsis thaliana. The subcellular distribution of ascorbate, glutathione, and hydrogen peroxide (H(2)O(2)) was analyzed by transmission electron microscopy and correlated with the activity of antioxidative enzymes in wildtype plants and the ascorbate- and glutathione-deficient mutants vtc2-1 and pad2-1, respectively. Both mutants showed earlier and stronger senescence than the wildtype indicating the importance of a functioning ascorbate and glutathione cycle in the induction and regulation of senescence. Glutathione levels dropped drastically and up to 93 % in all cell compartments of wildtype plants and the vtc2-1 mutant within the first day of dark-induced senescence while ascorbate contents remained unchanged until the very end. Glutathione contents in mitochondria of pad2-1 mutants decreased more slowly over the first 7 days than compared to the other plants indicating an important role of glutathione in mitochondria in this mutant during senescence. The strongest decrease (84 %) of glutathione contents in wildtype plants at this time point was found in mitochondria indicating an important role of mitochondria for the induction of senescence and cell death events. Due to the general decrease of the antioxidative capacity, a strong accumulation of H(2)O(2) was observed in cell walls, plastids, and the cytosol in all plants. Activities of glutathione reductase, dehydroascorbate reductase and catalase were strongly reduced while ascorbate peroxidase and monodehydroascorbate reductase were increased. The initial rapid drop of glutathione levels seemed to be the trigger for senescence, while ascorbate appeared to be the key factor in regulating senescence through controlling H(2)O(2) levels by the oxidation of reduced ascorbate to monodehydroascorbate and the subsequent reduction to ascorbate by monodehydroascorbate reductase. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11738-016-2150-6) contains supplementary material, which is available to authorized users.
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spelling pubmed-48598652016-05-21 Compartment-specific investigations of antioxidants and hydrogen peroxide in leaves of Arabidopsis thaliana during dark-induced senescence Luschin-Ebengreuth, Nora Zechmann, Bernd Acta Physiol Plant Original Article The aim of this study was to gain insight into the compartment-specific roles of ascorbate and glutathione in leaf senescence in Arabidopsis thaliana. The subcellular distribution of ascorbate, glutathione, and hydrogen peroxide (H(2)O(2)) was analyzed by transmission electron microscopy and correlated with the activity of antioxidative enzymes in wildtype plants and the ascorbate- and glutathione-deficient mutants vtc2-1 and pad2-1, respectively. Both mutants showed earlier and stronger senescence than the wildtype indicating the importance of a functioning ascorbate and glutathione cycle in the induction and regulation of senescence. Glutathione levels dropped drastically and up to 93 % in all cell compartments of wildtype plants and the vtc2-1 mutant within the first day of dark-induced senescence while ascorbate contents remained unchanged until the very end. Glutathione contents in mitochondria of pad2-1 mutants decreased more slowly over the first 7 days than compared to the other plants indicating an important role of glutathione in mitochondria in this mutant during senescence. The strongest decrease (84 %) of glutathione contents in wildtype plants at this time point was found in mitochondria indicating an important role of mitochondria for the induction of senescence and cell death events. Due to the general decrease of the antioxidative capacity, a strong accumulation of H(2)O(2) was observed in cell walls, plastids, and the cytosol in all plants. Activities of glutathione reductase, dehydroascorbate reductase and catalase were strongly reduced while ascorbate peroxidase and monodehydroascorbate reductase were increased. The initial rapid drop of glutathione levels seemed to be the trigger for senescence, while ascorbate appeared to be the key factor in regulating senescence through controlling H(2)O(2) levels by the oxidation of reduced ascorbate to monodehydroascorbate and the subsequent reduction to ascorbate by monodehydroascorbate reductase. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11738-016-2150-6) contains supplementary material, which is available to authorized users. Springer Berlin Heidelberg 2016-05-06 2016 /pmc/articles/PMC4859865/ /pubmed/27217598 http://dx.doi.org/10.1007/s11738-016-2150-6 Text en © The Author(s) 2016 Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.
spellingShingle Original Article
Luschin-Ebengreuth, Nora
Zechmann, Bernd
Compartment-specific investigations of antioxidants and hydrogen peroxide in leaves of Arabidopsis thaliana during dark-induced senescence
title Compartment-specific investigations of antioxidants and hydrogen peroxide in leaves of Arabidopsis thaliana during dark-induced senescence
title_full Compartment-specific investigations of antioxidants and hydrogen peroxide in leaves of Arabidopsis thaliana during dark-induced senescence
title_fullStr Compartment-specific investigations of antioxidants and hydrogen peroxide in leaves of Arabidopsis thaliana during dark-induced senescence
title_full_unstemmed Compartment-specific investigations of antioxidants and hydrogen peroxide in leaves of Arabidopsis thaliana during dark-induced senescence
title_short Compartment-specific investigations of antioxidants and hydrogen peroxide in leaves of Arabidopsis thaliana during dark-induced senescence
title_sort compartment-specific investigations of antioxidants and hydrogen peroxide in leaves of arabidopsis thaliana during dark-induced senescence
topic Original Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4859865/
https://www.ncbi.nlm.nih.gov/pubmed/27217598
http://dx.doi.org/10.1007/s11738-016-2150-6
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