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Pavlíková D, Zemanová V, Pavlík M, Dobrev PI, Hnilička F, Motyka V. Response of cytokinins and nitrogen metabolism in the fronds of Pteris sp. under arsenic stress. PLoS One 2020; 15:e0233055. [PMID: 32413087 PMCID: PMC7228123 DOI: 10.1371/journal.pone.0233055] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 04/27/2020] [Indexed: 12/13/2022] Open
Abstract
Given the close relationship between cytokinins (CKs), photosynthesis and nitrogen metabolism, this study assessed the effect of arsenic (As) contamination on these metabolic components in the As-hyperaccumulators Pteris cretica L. var. Albo-lineata (Pc-A) and var. Parkerii (Pc-P) as well as the As-non-hyperaccumulator Pteris straminea Mett. ex Baker (Ps). The ferns were cultivated in a pot experiment for 23 weeks in soil spiked with As at the levels 20 and 100 mg·kg-1. For the purpose of this study, the CKs were placed into five functionally different groups according to their structure and physiological roles: bioactive forms (bCKs; CK free bases); inactive or weakly active forms (dCKs; CK N-glucosides); transport forms (tCKs; CK ribosides); storage forms (sCKs; O-glucosides); and primary products of CK biosynthesis (ppbCKs; CK nucleotides). An important finding was higher CKs total content, accumulation of sCKs and reduction of dCKs in As-hyperaccumulators in contrast to non-hyperaccumulator ferns. A significant depletion of C resources was confirmed in ferns, especially Ps, which was determined by measuring the photosynthetic rate and chlorophyll fluorescence. A fluorescence decrease signified a reduction in the C/N ratio, inducing an increase of bioactive CKs forms in Pc-P and Ps. The impact of As on N utilization was significant in As-hyperaccumulators. The glutamic acid/glutamine ratio, an indicator of primary N assimilation, diminished in all ferns with increased As level in the soil. In conclusion, the results indicate a large phenotypic diversity of Pteris species to As and suggest that the CKs composition and the glutamic acid/glutamine ratio can be used as a tool to diagnose As stress in plants.
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Affiliation(s)
- Daniela Pavlíková
- Department of Agro-Environmental Chemistry and Plant Nutrition, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Veronika Zemanová
- Department of Agro-Environmental Chemistry and Plant Nutrition, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Prague, Czech Republic
- Isotope Laboratory, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czech Republic
| | - Milan Pavlík
- Department of Agro-Environmental Chemistry and Plant Nutrition, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Prague, Czech Republic
- Isotope Laboratory, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czech Republic
| | - Petre I. Dobrev
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czech Republic
| | - František Hnilička
- Department of Botany and Plant Physiology, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Václav Motyka
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czech Republic
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Stoyneva-Gärtner M, Uzunov B, Gärtner G, Radkova M, Atanassov I, Atanasova R, Borisova C, Draganova P, Stoykova P. Review on the biotechnological and nanotechnological potential of the streptophyte genus Klebsormidium with pilot data on its phycoprospecting and polyphasic identification in Bulgaria. BIOTECHNOL BIOTEC EQ 2019. [DOI: 10.1080/13102818.2019.1593887] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Affiliation(s)
- Maya Stoyneva-Gärtner
- Department of Botany, Faculty of Biology, Sofia University “St. Kliment Ohridski”, Sofia, Bulgaria
| | - Blagoy Uzunov
- Department of Botany, Faculty of Biology, Sofia University “St. Kliment Ohridski”, Sofia, Bulgaria
| | - Georg Gärtner
- Institut für Botanik, Fakultät für Biologie, Universität Innsbruck, Innsbruck, Austria
| | - Mariana Radkova
- Functional Genetics Legumes Group, AgroBioInstitute, Agricultural Academy, Sofia, Bulgaria
| | - Ivan Atanassov
- Molecular Genetics Group, AgroBioInstitute, Agricultural Academy, Sofia, Bulgaria
| | - Ralitsa Atanasova
- Department of Botany, Faculty of Biology, Sofia University “St. Kliment Ohridski”, Sofia, Bulgaria
| | - Cvetanka Borisova
- Department of Botany, Faculty of Biology, Sofia University “St. Kliment Ohridski”, Sofia, Bulgaria
| | - Petya Draganova
- Department of Botany, Faculty of Biology, Sofia University “St. Kliment Ohridski”, Sofia, Bulgaria
| | - Petya Stoykova
- Functional Genetics Legumes Group, AgroBioInstitute, Agricultural Academy, Sofia, Bulgaria
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Hönig M, Plíhalová L, Husičková A, Nisler J, Doležal K. Role of Cytokinins in Senescence, Antioxidant Defence and Photosynthesis. Int J Mol Sci 2018; 19:E4045. [PMID: 30558142 PMCID: PMC6321018 DOI: 10.3390/ijms19124045] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 12/05/2018] [Accepted: 12/12/2018] [Indexed: 01/13/2023] Open
Abstract
Cytokinins modulate a number of important developmental processes, including the last phase of leaf development, known as senescence, which is associated with chlorophyll breakdown, photosynthetic apparatus disintegration and oxidative damage. There is ample evidence that cytokinins can slow down all these senescence-accompanying changes. Here, we review relationships between the various mechanisms of action of these regulatory molecules. We highlight their connection to photosynthesis, the pivotal process that generates assimilates, however may also lead to oxidative damage. Thus, we also focus on cytokinin induction of protective responses against oxidative damage. Activation of antioxidative enzymes in senescing tissues is described as well as changes in the levels of naturally occurring antioxidative compounds, such as phenolic acids and flavonoids, in plant explants. The main goal of this review is to show how the biological activities of cytokinins may be related to their chemical structure. New links between molecular aspects of natural cytokinins and their synthetic derivatives with antisenescent properties are described. Structural motifs in cytokinin molecules that may explain why these molecules play such a significant regulatory role are outlined.
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Affiliation(s)
- Martin Hönig
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
| | - Lucie Plíhalová
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
| | - Alexandra Husičková
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
| | - Jaroslav Nisler
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
| | - Karel Doležal
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
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Janečková H, Husičková A, Ferretti U, Prčina M, Pilařová E, Plačková L, Pospíšil P, Doležal K, Špundová M. The interplay between cytokinins and light during senescence in detached Arabidopsis leaves. PLANT, CELL & ENVIRONMENT 2018; 41:1870-1885. [PMID: 29744884 DOI: 10.1111/pce.13329] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 04/13/2018] [Accepted: 04/23/2018] [Indexed: 05/06/2023]
Abstract
Light and cytokinins are known to be the key players in the regulation of plant senescence. In detached leaves, the retarding effect of light on senescence is well described; however, it is not clear to what extent is this effect connected with changes in endogenous cytokinin levels. We have performed a detailed analysis of changes in endogenous content of 29 cytokinin forms in detached leaves of Arabidopsis thaliana (wild-type and 3 cytokinin receptor double mutants). Leaves were kept under different light conditions, and changes in cytokinin content were correlated with changes in chlorophyll content, efficiency of photosystem II photochemistry, and lipid peroxidation. In leaves kept in darkness, we have observed decreased content of the most abundant cytokinin free bases and ribosides, but the content of cis-zeatin increased, which indicates the role of this cytokinin in the maintenance of basal leaf viability. Our findings underscore the importance of light conditions on the content of specific cytokinins, especially N6 -(Δ2 -isopentenyl)adenine. On the basis of our results, we present a scheme summarizing the contribution of the main active forms of cytokinins, cytokinin receptors, and light to senescence regulation. We conclude that light can compensate the disrupted cytokinin signalling in detached leaves.
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Affiliation(s)
- Helena Janečková
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Biophysics, Faculty of Science, Palacký University, 78371, Olomouc, Czech Republic
| | - Alexandra Husičková
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Biophysics, Faculty of Science, Palacký University, 78371, Olomouc, Czech Republic
| | - Ursula Ferretti
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Biophysics, Faculty of Science, Palacký University, 78371, Olomouc, Czech Republic
| | - Maroš Prčina
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Biophysics, Faculty of Science, Palacký University, 78371, Olomouc, Czech Republic
| | - Eva Pilařová
- Laboratory of Growth Regulators, Faculty of Science, Palacký University & Institute of Experimental Botany AS CR, 78371, Olomouc, Czech Republic
| | - Lenka Plačková
- Laboratory of Growth Regulators, Faculty of Science, Palacký University & Institute of Experimental Botany AS CR, 78371, Olomouc, Czech Republic
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Chemical Biology and Genetics, Faculty of Science, Palacký University, 78371, Olomouc, Czech Republic
| | - Pavel Pospíšil
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Biophysics, Faculty of Science, Palacký University, 78371, Olomouc, Czech Republic
| | - Karel Doležal
- Laboratory of Growth Regulators, Faculty of Science, Palacký University & Institute of Experimental Botany AS CR, 78371, Olomouc, Czech Republic
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Chemical Biology and Genetics, Faculty of Science, Palacký University, 78371, Olomouc, Czech Republic
| | - Martina Špundová
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Biophysics, Faculty of Science, Palacký University, 78371, Olomouc, Czech Republic
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Zdarska M, Dobisová T, Gelová Z, Pernisová M, Dabravolski S, Hejátko J. Illuminating light, cytokinin, and ethylene signalling crosstalk in plant development. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:4913-31. [PMID: 26022257 DOI: 10.1093/jxb/erv261] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Integrating important environmental signals with intrinsic developmental programmes is a crucial adaptive requirement for plant growth, survival, and reproduction. Key environmental cues include changes in several light variables, while important intrinsic (and highly interactive) regulators of many developmental processes include the phytohormones cytokinins (CKs) and ethylene. Here, we discuss the latest discoveries regarding the molecular mechanisms mediating CK/ethylene crosstalk at diverse levels of biosynthetic and metabolic pathways and their complex interactions with light. Furthermore, we summarize evidence indicating that multiple hormonal and light signals are integrated in the multistep phosphorelay (MSP) pathway, a backbone signalling pathway in plants. Inter alia, there are strong overlaps in subcellular localizations and functional similarities in components of these pathways, including receptors and various downstream agents. We highlight recent research demonstrating the importance of CK/ethylene/light crosstalk in selected aspects of plant development, particularly seed germination and early seedling development. The findings clearly demonstrate the crucial integration of plant responses to phytohormones and adaptive responses to environmental cues. Finally, we tentatively identify key future challenges to refine our understanding of the molecular mechanisms mediating crosstalk between light and hormonal signals, and their integration during plant life cycles.
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Affiliation(s)
- Marketa Zdarska
- Functional Genomics and Proteomics of Plants, Central European Institute of Technology and National Centre for Biomolecular Research, Masaryk University, Brno 62500, Czech Republic
| | - Tereza Dobisová
- Functional Genomics and Proteomics of Plants, Central European Institute of Technology and National Centre for Biomolecular Research, Masaryk University, Brno 62500, Czech Republic
| | - Zuzana Gelová
- Functional Genomics and Proteomics of Plants, Central European Institute of Technology and National Centre for Biomolecular Research, Masaryk University, Brno 62500, Czech Republic
| | - Markéta Pernisová
- Functional Genomics and Proteomics of Plants, Central European Institute of Technology and National Centre for Biomolecular Research, Masaryk University, Brno 62500, Czech Republic
| | - Siarhei Dabravolski
- Functional Genomics and Proteomics of Plants, Central European Institute of Technology and National Centre for Biomolecular Research, Masaryk University, Brno 62500, Czech Republic
| | - Jan Hejátko
- Functional Genomics and Proteomics of Plants, Central European Institute of Technology and National Centre for Biomolecular Research, Masaryk University, Brno 62500, Czech Republic
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Du J, Li M, Kong D, Wang L, Lv Q, Wang J, Bao F, Gong Q, Xia J, He Y. Nitric oxide induces cotyledon senescence involving co-operation of the NES1/MAD1 and EIN2-associated ORE1 signalling pathways in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:4051-63. [PMID: 24336389 PMCID: PMC4106434 DOI: 10.1093/jxb/ert429] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
After germination, cotyledons undertake the major role in supplying nutrients to the pre-photoautorophy angiosperm seedlings until they senesce. Like other senescence processes, cotyledon senescence is a programmed degenerative process. Nitric oxide can induce premature cotyledon senescence in Arabidopsis thaliana, yet the underlying mechanism remains elusive. A screen for genetic mutants identified the nes1 mutant, in which cotyledon senescence was accelerated by nitric oxide. Map-based cloning revealed that NES1 is allelic to a previously reported mitotic checkpoint family gene, MAD1. The nes1/mad1 mutants were restored to the wild type, in response to nitric oxide, by transforming them with pNES1::NES1. Ectopic expression of NES1 in the wild type delayed nitric oxide-mediated cotyledon senescence, confirming the repressive role of NES1. Moreover, two positive regulators of leaf senescence, the ethylene signalling component EIN2 and the transcription factor ORE1/AtNAC2/ANAC092, were found to function during nitric oxide-induced senescence in cotyledons. The block of ORE1 function delayed senescence and ectopic expression induced the process, revealing the positive role of ORE1. EIN2 was required to induce ORE1. Furthermore, the genetic interaction analysis between NES1 and ORE1 showed that the ore1 loss-of-function mutants were epistatic to nes1, suggesting the dominant role of ORE1 and the antagonistic role of NES1 during nitric oxide-induced cotyledon senescence in Arabidopsis.
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Affiliation(s)
- Jing Du
- College of Life Sciences, Capital Normal University, Beijing, 100048, PR China
| | - Manli Li
- College of Life Sciences, Capital Normal University, Beijing, 100048, PR China
| | - Dongdong Kong
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
| | - Lei Wang
- College of Life Sciences, Capital Normal University, Beijing, 100048, PR China
| | - Qiang Lv
- College of Life Sciences, Capital Normal University, Beijing, 100048, PR China
| | - Jinzheng Wang
- College of Life Sciences, Capital Normal University, Beijing, 100048, PR China
| | - Fang Bao
- College of Life Sciences, Capital Normal University, Beijing, 100048, PR China
| | - Qingqiu Gong
- College of Life Sciences, Nankai University, Tianjin, 300071, PR China
| | - Jinchan Xia
- College of Life Sciences, Capital Normal University, Beijing, 100048, PR China
| | - Yikun He
- College of Life Sciences, Capital Normal University, Beijing, 100048, PR China
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7
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Han RM, Lefèvre I, Albacete A, Pérez-Alfocea F, Barba-Espín G, Díaz-Vivancos P, Quinet M, Ruan CJ, Hernández JA, Cantero-Navarro E, Lutts S. Antioxidant enzyme activities and hormonal status in response to Cd stress in the wetland halophyte Kosteletzkya virginica under saline conditions. PHYSIOLOGIA PLANTARUM 2013; 147:352-68. [PMID: 22697433 DOI: 10.1111/j.1399-3054.2012.01667.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 05/16/2012] [Accepted: 05/22/2012] [Indexed: 05/20/2023]
Abstract
Salt marshes constitute major sinks for heavy metal accumulation but the precise impact of salinity on heavy metal toxicity for halophyte plant species remains largely unknown. Young seedlings of Kosteletzkya virginica were exposed during 3 weeks in nutrient solution to Cd 5 µM in the presence or absence of 50 mM NaCl. Cadmium (Cd) reduced growth and shoot water content and had major detrimental effect on maximum quantum efficiency (F(v) /F(m) ), effective quantum yield of photosystem II (Y(II)) and electron transport rates (ETRs). Cd induced an oxidative stress in relation to an increase in O(2) (•-) and H(2) O(2) concentration and lead to a decrease in endogenous glutathione (GSH) and α-tocopherol in the leaves. Cd not only increased leaf zeatin and zeatin riboside concentration but also increased the senescing compounds 1-aminocyclopropane-1-carboxylic acid (ACC) and abscisic acid (ABA). Salinity reduced Cd accumulation already after 1 week of stress but was unable to restore shoot growth and thus did not induce any dilution effect. Salinity delayed the Cd-induced leaf senescence: NaCl reduced the deleterious impact of Cd on photosynthesis apparatus through an improvement of F(v) /F(m) , Y(II) and ETR. Salt reduced oxidative stress in Cd-treated plants through an increase in GSH, α-tocopherol and ascorbic acid synthesis and an increase in glutathione reductase (EC 1.6.4.2) activity. Additional salt reduced ACC and ABA accumulation in Cd+NaCl-treated leaves comparing to Cd alone. It is concluded that salinity affords efficient protection against Cd to the halophyte species K. virginica, in relation to an improved management of oxidative stress and hormonal status.
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Affiliation(s)
- Rui-Ming Han
- Groupe de Recherche en Physiologie végétale (GRPV), Earth and Life Institute - Agronomy (ELI-A), Université catholique de Louvain (UCL), Croix du Sud 5, bte L 7.07.13, B-1348, Louvain-la-Neuve, Belgium
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Schlüter T, Leide J, Conrad K. Light promotes an increase of cytokinin oxidase/dehydrogenase activity during senescence of barley leaf segments. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:694-698. [PMID: 21106275 DOI: 10.1016/j.jplph.2010.10.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Revised: 10/19/2010] [Accepted: 10/19/2010] [Indexed: 05/30/2023]
Abstract
Following a study of the relationship between cytokinin oxidase/dehydrogenase (CKX) and senescence in darkened barley leaf segments, we have now investigated the influence of light on the in vitro activity of CKX. Seedlings of Hordeum vulgare L. were grown for 8d under a light/dark regime of 18h white light and 6h darkness. Then apical parts of 7cm length were cut from the first foliage leaves and their bases were placed in water. In segments kept in the dark, the CKX activity measured by cleavage of N(6)-(Δ(2)-isopentenyl)adenine rose from 0.1pkat (gFW)(-1) to 0.8pkat (g initial FW)(-1) within the first 4d of incubation. In contrast, in segments kept under the light/dark regime it reached a value of 8.6pkat (g initial FW)(-1) over the same time period. The chlorophyll a content declined slightly slower during light/dark cycling than in darkness. In contrast to segments and isolated laminae, corresponding attached laminae exhibited less CKX activity after 2d under light/dark conditions than after 2d in the dark. The activity in attached laminae of first foliage leaves of plants growing in light/dark cycling increased strongly only when the plants were older than 4 weeks. In line with this, the CKX activity in attached laminae of flag leaves of barley growing in fields increased in a late developmental state. The senescence of darkened isolated laminae of Zea mays L. and Phragmites australis (Cav.) Trin. ex Steudel was associated with an enhancement of CKX activity too. Because in most cases a positive correlation between CKX activity and senescence was found, it is likely that the enzyme promotes senescence by destroying cytokinins, which help to keep Poaceae leaves green. Light may promote not only cytokinin degradation but also the formation of bioactive cytokinins in leaf segments.
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Affiliation(s)
- Torsten Schlüter
- Ernst-Moritz-Arndt-Universität Greifswald, Physiologisches Institut, Greifswalder Strasse 11c, D-17495 Karlsburg, Germany.
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