caa a22 4500 467894221 CHVBK 20180406152758.0 cr unu---uuuuu 170328e20060701xx s 000 0 eng 10.1007/s11103-006-0045-4 doi (NATIONALLICENCE)springer-10.1007/s11103-006-0045-4 Heat stress-induced H2O2 is required for effective expression of heat shock genes in Arabidopsis [Elektronische Daten] [Roman Volkov, Irina Panchuk, Phillip Mullineaux, Friedrich Schöffl] The mechanisms of sensing and signalling of heat and oxidative stresses are not well understood. The central question of this paper is whether in plant cells oxidative stress, in particular H2O2, is required for heat stress- and heat shock factor (HSF)-dependent expression of genes. Heat stress increases intracellular accumulation of H2O2 in Arabidopsis cell culture. The accumulation was greatly diminished using ascorbate as a scavenger or respectively diphenyleneiodonium chloride (DPI) as an inhibitor of reactive oxygen species production. The mRNA of heat shock protein (HSP) genes, exemplified by Hsp17.6, Hsp18.2, and the two cytosolic ascorbate peroxidase genes Apx1, Apx2, reached similar levels by moderate heat stress (37°C) or by treatment with H2O2, butylperoxide and diamide at room temperature. The heat-induced expression levels were significantly reduced in the presence of ascorbate or DPI indicating that H2O2 is an essential component in the heat stress signalling pathway. Rapid (15min) formation of heat shock promoter element (HSE) protein-binding complex of high molecular weight in extracts of heat-stressed or H2O2-treated cells and the inability to form this complex after ascorbate treatment suggests that oxidative stress affects gene expression via HSF activation and conversely, that H2O2 is involved in HSF activation during the early phase of heat stress. The heat stress induction of a high mobility HSE-binding complex, characteristic for later phase of heat shock response, was blocked by ascorbate and DPI. H2O2 was unable to induce this complex suggesting that H2O2 is involved only in the early stages of HSF activation. Significant induction of the genes tested after diamid treatment and moderate expression of the sHSP genes in the presence of 50mM ascorbate at 37°C occurred without activation of HSF, indicating that other mechanisms may be involved in stress signalling. Springer Science+Business Media B.V., 2006 Ascorbate peroxidase nationallicence DPI nationallicence Heat shock factor nationallicence Heat shock protein nationallicence Hydrogen peroxide nationallicence Oxidative stress nationallicence Volkov Roman Zentrum für Molekularbiologie der Pflanzen - Allgemeine Genetik, Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany aut Panchuk Irina Zentrum für Molekularbiologie der Pflanzen - Allgemeine Genetik, Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany aut Mullineaux Phillip Department of Biological Sciences, University of Essex, Wivenhoe Park, CO4 3SQ, Colchester, Essex, UK aut Schöffl Friedrich Zentrum für Molekularbiologie der Pflanzen - Allgemeine Genetik, Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany aut Plant Molecular Biology Kluwer Academic Publishers 61/4-5(2006-07-01), 733-746 0167-4412 61:4-5<733 2006 61 11103 https://doi.org/10.1007/s11103-006-0045-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11103-006-0045-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Volkov Roman Zentrum für Molekularbiologie der Pflanzen - Allgemeine Genetik, Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany aut NATIONALLICENCE 700 1- Panchuk Irina Zentrum für Molekularbiologie der Pflanzen - Allgemeine Genetik, Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany aut NATIONALLICENCE 700 1- Mullineaux Phillip Department of Biological Sciences, University of Essex, Wivenhoe Park, CO4 3SQ, Colchester, Essex, UK aut NATIONALLICENCE 700 1- Schöffl Friedrich Zentrum für Molekularbiologie der Pflanzen - Allgemeine Genetik, Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany aut NATIONALLICENCE 773 0- Plant Molecular Biology Kluwer Academic Publishers 61/4-5(2006-07-01), 733-746 0167-4412 61:4-5<733 2006 61 11103 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer