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Prerostova S, Dobrev PI, Gaudinova A, Knirsch V, Körber N, Pieruschka R, Fiorani F, Brzobohatý B, černý M, Spichal L, Humplik J, Vanek T, Schurr U, Vankova R. Cytokinins: Their Impact on Molecular and Growth Responses to Drought Stress and Recovery in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2018; 9:655. [PMID: 29872444 PMCID: PMC5972670 DOI: 10.3389/fpls.2018.00655] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 04/27/2018] [Indexed: 05/02/2023]
Abstract
Our phenotyping and hormonal study has characterized the role of cytokinins (CK) in the drought and recovery responses of Arabidopsis thaliana. CK down-regulation was achieved by overexpression of the gene for CK deactivating enzyme cytokinin oxidase/dehydrogenase (CKX): constitutive (35S:CKX) or at the stress onset using a dexamethasone-inducible pOp/LhGR promoter (DEX:CKX). The 35S:CKX plants exhibited slow ontogenesis and higher expression levels of stress-associated genes, e.g., AtP5CS1, already at well-watered conditions. CK down-regulation resulted during drought in higher stress tolerance (indicated by relatively low up-regulation of the expression of drought stress marker gene AtRD29B) accompanied with lower leaf water loss. Nevertheless, these plants exhibited slow and delayed recovery after re-watering. CK levels were increased at the stress onset by stimulation of the expression of CK biosynthetic gene isopentenyl transferase (ipt) (DEX:IPT) or by application of exogenous CK meta-topolin. After water withdrawal, long-term CK elevation resulted in higher water loss in comparison with CKX transformants as well as with plants overexpressing ipt driven by senescence-inducible SAG12 promoter (SAG:IPT), which gradually enhanced CKs during the stress progression. In all cases, CK up-regulation resulted in fast and more vigorous recovery. All drought-stressed plants exhibited growth suppression associated with elevation of abscisic acid and decrease of auxins and active CKs (with the exception of SAG:IPT plants). Apart from the ipt overexpressers, also increase of jasmonic and salicylic acid was found.
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Affiliation(s)
- Sylva Prerostova
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Prague, Czechia
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Prague, Czechia
| | - Petre I. Dobrev
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Prague, Czechia
| | - Alena Gaudinova
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Prague, Czechia
| | - Vojtech Knirsch
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Prague, Czechia
| | - Niklas Körber
- IBG-2: Plant Sciences, Institute for Bio-and Geosciences, Forschungszentrum Jülich, Jülich, Germany
| | - Roland Pieruschka
- IBG-2: Plant Sciences, Institute for Bio-and Geosciences, Forschungszentrum Jülich, Jülich, Germany
| | - Fabio Fiorani
- IBG-2: Plant Sciences, Institute for Bio-and Geosciences, Forschungszentrum Jülich, Jülich, Germany
| | - Břetislav Brzobohatý
- Laboratory of Plant Molecular Biology, Institute of Biophysics AS and CR — Central European Institute of Technology, Mendel University in Brno, Brno, Czechia
| | - Martin černý
- Laboratory of Plant Molecular Biology, Institute of Biophysics AS and CR — Central European Institute of Technology, Mendel University in Brno, Brno, Czechia
| | - Lukas Spichal
- Department of Chemical Biology and Genetics, Centre of the Region Hana for Biotechnological and Agricultural Research, Institute of Experimental Botany Czech Academy of Sciences and Faculty of Science of Palacky University, Olomouc, Czechia
| | - Jan Humplik
- Laboratory of Growth Regulators, Centre of the Region Hana for Biotechnological and Agricultural Research, Institute of Experimental Botany Czech Academy of Sciences, Faculty of Science of Palacky University, Olomouc, Czechia
| | - Tomas Vanek
- Laboratory of Plant Biotechnologies, Institute of Experimental Botany, Czech Academy of Sciences, Prague, Czechia
| | - Ulrich Schurr
- IBG-2: Plant Sciences, Institute for Bio-and Geosciences, Forschungszentrum Jülich, Jülich, Germany
| | - Radomira Vankova
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Prague, Czechia
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