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Arora K, Sen S. Cytokinin Oxygenase/Dehydrogenase Inhibitors: An Emerging Tool in Stress Biotechnology Employed for Crop Improvement. Front Genet 2022; 13:877510. [PMID: 35401687 PMCID: PMC8987495 DOI: 10.3389/fgene.2022.877510] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 03/04/2022] [Indexed: 12/02/2022] Open
Abstract
In order to meet the global challenges of food security, one of the foremost solutions lies in enhancing the crop productivity. This can be attained by considering key plant hormones such as cytokinins as agrochemicals as cytokinins in particular are known to control the essential processes of the plants. Even though, it has already been established since 1980s that the enzyme, cytokinin oxidase/dehydrogenase (CKO/CKX) deactivates cytokinins; the potential applications of manipulating these enzymes have mostly been speculated to have a high potential in the biotechnology industry and spreads to agriculture, horticulture and agroforestry. The enzyme is critical in maintaining a balanced level of cytokinins in plants. However, it is yet to be fully established that inhibiting this enzyme can be the constant source of improvement in the productivity of plants, even though success has been obtained in some economically important plant species. Furthermore, the impact efficiency of this enzyme may vary from plant to plant, which needs to be evaluated employing tissue culture and other extrinsic applications. This review intends to cover the relevant studies addressing any biological activity of this enzyme in the current context and any associated biotechnological applications specific to enhanced grain yield, abiotic stress tolerance, delayed senescence and in vitro organogenesis among various plants and not only cereals. Moreover, our study will identify the present gaps in research with respect to many important food crops, which will be useful for researchers who are actively involved in providing a foundation for a variety of genetically improved plants achieved through this manner. In addition to this, other ways of engineering the amount of cytokinin levels appropriate for signaling also needs to be analyzed in order to extend the benefits of cytokinin biology to other crops too. The application of these inhibitors can be considered among the best alternates as well as addition to genetically modified plants for overcoming the gaps in crop demand.
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Affiliation(s)
- Kavita Arora
- Department of Botany, National P.G. College, Lucknow, India
- *Correspondence: Kavita Arora, ; Sangeeta Sen,
| | - Sangeeta Sen
- Bangalore, India
- *Correspondence: Kavita Arora, ; Sangeeta Sen,
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Kaźmierczak A, Kunikowska A, Doniak M, Kornaś A. Mechanism of kinetin-induced death of Vicia faba ssp. minor root cortex cells. Sci Rep 2021; 11:23746. [PMID: 34887458 PMCID: PMC8660813 DOI: 10.1038/s41598-021-03103-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 11/16/2021] [Indexed: 01/03/2023] Open
Abstract
Cell death (CD) may be induced by endogenous or exogenous factors and contributes to all the steps of plant development. This paper presents results related to the mechanism of CD regulation induced by kinetin (Kin) in the root cortex of Vicia faba ssp. minor. To explain the process, 6-(2-hydroxy-3-methylbenzylamino)purine (PI-55), adenine (Ad), 5'-amine-5'-deoxyadenosine (Ado) and N-(2-chloro-4-piridylo)-N'-phenylurea (CPPU) were applied to (i) block cytokinin receptors (CKs) and inhibit the activities of enzymes of CK metabolism, i.e., (ii) phosphoribosyltransferase, (iii) kinases, and (iv) oxidases, respectively. Moreover, ethylene glycol-bis(β-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA), lanthanum chloride (LaCl3), ruthenium red (RRed) and cyclosporine A (CS-A) were applied to (i) chelate extracellular calcium ions (Ca2+) as well as blocks of (ii) plasma-, (iii) endoplasmic reticulum- (ER) membrane Ca2+ ion channels and (iv) mitochondria- (MIT) Ca2+ ions release by permeability transition por (PTP), respectively. The measured physiological effectiveness of these factors was the number of living and dying cortex cells estimated with orange acridine (OA) and ethidium bromide (EB), the amounts of cytosolic Ca2+ ions with chlortetracycline (CTC) staining and the intensity of chromatin and Ca2+-CTC complex fluorescence, respectively. Moreover, the role of sorafenib, an inhibitor of RAF kinase, on the vitality of cortex cells and ethylene levels as well as the activities of RAF-like kinase and MEK2 with Syntide-2 and Mek2 as substrates were studied. The results clarified the previously presented suggestion that Kin is converted to appropriate ribotides (5'-monophosphate ribonucleotides), which cooperate with the ethylene and Ca2+ ion signalling pathways to transduce the signal of kinetin-programmed cell death (Kin-PCD). Based on the present and previously published results related to Kin-PCD, the crosstalk between ethylene and MAP kinase signalling, as well as inhibitors of CK receptors and enzymes of their metabolism, is proposed.
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Affiliation(s)
- Andrzej Kaźmierczak
- Department of Cytophysiology, Institute of Experimental Biology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/143, 90-236, Lodz, Poland.
| | - Anita Kunikowska
- Department of Cytophysiology, Institute of Experimental Biology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/143, 90-236, Lodz, Poland
| | - Magdalena Doniak
- Department of Cytophysiology, Institute of Experimental Biology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/143, 90-236, Lodz, Poland
| | - Andrzej Kornaś
- Institute of Biology, Pedagogical University of Krakow, Podchorążych 2, 30-084, Kraków, Poland
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van Voorthuizen MJ, Song J, Novák O, Jameson PE. Plant Growth Regulators INCYDE and TD-K Underperform in Cereal Field Trials. PLANTS (BASEL, SWITZERLAND) 2021; 10:plants10112309. [PMID: 34834672 PMCID: PMC8618831 DOI: 10.3390/plants10112309] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 10/22/2021] [Indexed: 06/13/2023]
Abstract
Using plant growth regulators to alter cytokinin homeostasis with the aim of enhancing endogenous cytokinin levels has been proposed as a strategy to increase yields in wheat and barley. The plant growth regulators INCYDE and CPPU inhibit the cytokinin degrading enzyme cytokinin oxidase/dehydrogenase (CKX), while TD-K inhibits the process of senescence. We report that the application of these plant growth regulators in wheat and barley field trials failed to enhance yields, or change the components of yields. Analyses of the endogenous cytokinin content showed a high concentration of trans-zeatin (tZ) in both wheat and barley grains at four days after anthesis, and statistically significant, but probably biologically insignificant, increases in cisZ-O-glucoside, along with small decreases in cZ riboside (cZR), dihydro Z (DHZ), and DHZR and DHZOG cytokinins, following INCYDE application to barley at anthesis. We discuss possible reasons for the lack of efficacy of the three plant growth regulators under field conditions and comment on future approaches to manipulating yield in the light of the strong homeostatic mechanisms controlling endogenous cytokinin levels.
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Affiliation(s)
- Matthew J. van Voorthuizen
- School of Biological Sciences, University of Canterbury, Christchurch 8140, New Zealand; (M.J.v.V.); (J.S.)
| | - Jiancheng Song
- School of Biological Sciences, University of Canterbury, Christchurch 8140, New Zealand; (M.J.v.V.); (J.S.)
- School of Life Sciences, Yantai University, Yantai 264005, China
| | - Ondřej Novák
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences & Faculty of Science of Palacký University, CZ-783 71 Olomouc, Czech Republic;
| | - Paula E. Jameson
- School of Biological Sciences, University of Canterbury, Christchurch 8140, New Zealand; (M.J.v.V.); (J.S.)
- School of Life Sciences, Yantai University, Yantai 264005, China
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Nisler J, Kopečný D, Pěkná Z, Končitíková R, Koprna R, Murvanidze N, Werbrouck SPO, Havlíček L, De Diego N, Kopečná M, Wimmer Z, Briozzo P, Moréra S, Zalabák D, Spíchal L, Strnad M. Diphenylurea-derived cytokinin oxidase/dehydrogenase inhibitors for biotechnology and agriculture. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:355-370. [PMID: 32945834 DOI: 10.1093/jxb/eraa437] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 09/17/2020] [Indexed: 05/11/2023]
Abstract
Increasing crop productivity is our major challenge if we are to meet global needs for food, fodder and fuel. Controlling the content of the plant hormone cytokinin is a method of improving plant productivity. Cytokinin oxidase/dehydrogenase (CKO/CKX) is a major target in this regard because it degrades cytokinins. Here, we describe the synthesis and biological activities of new CKX inhibitors derived mainly from diphenylurea. They were tested on four CKX isoforms from maize and Arabidopsis, where the best compounds showed IC50 values in the 10-8 M concentration range. The binding mode of the most efficient inhibitors was characterized from high-resolution crystal complexed structures. Although these compounds do not possess intrinsic cytokinin activity, we have demonstrated their tremendous potential for use in the plant tissue culture industry as well as in agriculture. We have identified a key substance, compound 19, which not only increases stress resistance and seed yield in Arabidopsis, but also improves the yield of wheat, barley and rapeseed grains under field conditions. Our findings reveal that modulation of cytokinin levels via CKX inhibition can positively affect plant growth, development and yield, and prove that CKX inhibitors can be an attractive target in plant biotechnology and agriculture.
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Affiliation(s)
- Jaroslav Nisler
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences & Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
- Department of Chemistry of Natural Compounds, Faculty of Food and Biochemical Technology, University of Chemistry and Technology in Prague, Technická 5, Prague, Czech Republic
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - David Kopečný
- Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - Zuzana Pěkná
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - Radka Končitíková
- Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - Radoslav Koprna
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - Nino Murvanidze
- Department Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Stefaan P O Werbrouck
- Department Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Libor Havlíček
- Isotope Laboratory, Institute of Experimental Botany, The Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic
| | - Nuria De Diego
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - Martina Kopečná
- Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - Zdeněk Wimmer
- Department of Chemistry of Natural Compounds, Faculty of Food and Biochemical Technology, University of Chemistry and Technology in Prague, Technická 5, Prague, Czech Republic
- Isotope Laboratory, Institute of Experimental Botany, The Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic
| | - Pierre Briozzo
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Route de Saint-Cyr, Versailles, France
| | - Solange Moréra
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, Gif-sur-Yvette, France
| | - David Zalabák
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - Lukáš Spíchal
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences & Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
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Targeting Cytokinin Homeostasis in Rapid Cycling Brassica rapa with Plant Growth Regulators INCYDE and TD-K. PLANTS 2020; 10:plants10010039. [PMID: 33375745 PMCID: PMC7824111 DOI: 10.3390/plants10010039] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/19/2020] [Accepted: 12/22/2020] [Indexed: 01/25/2023]
Abstract
Modifying the cytokinin content in plants is a means of improving plant productivity. Here, we report the development and biological activity of compound TD-K (1-(furan-2-ylmethyl)-3-(1,2,3-thiadiazol-5-yl)urea)which is related to thidiazuron. TD-K—which exhibited extremely high antisenescence activity in the wheat leaf bioassay—and INCYDE (2-chloro-6-(3-methoxyphenyl)aminopurine)—a plant growth regulator reported to inhibit cytokinin oxidase/dehydrogenase (CKX), an enzyme involved in the degradation of the plant hormone cytokinin—were selected for investigation of their effects on the model plant Rapid Cycling Brassica rapa (RCBr). We monitored the expression of BrCKX and isopentenyl transferase (BrIPT), which codes for the key cytokinin biosynthesis enzyme, in developing leaves following INCYDE and TD-K application. Growth room experiments revealed that INCYDE increased RCBr seed yield per plant, but only when applied multiple times and when grown in 5 mM KNO3. Expression in control leaves showed transient, high levels of expression of BrCKX and BrIPT at true leaf appearance. Following INCYDE application, there was a rapid and strong upregulation of BrCKX3, and a transient downregulation of BrIPT1 and BrIPT3. Interestingly, the upregulation of BrCKX3 persisted in a milder form throughout the course of the experiment (16 days). TD-K also upregulated BrCKX3. However, in contrast to INCYDE, this effect disappeared after two days. These results suggest that both compounds (CKX inhibitor and cytokinin TD-K) influenced cytokinin homeostasis in RCBr leaves, but with different mechanisms.
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Goh DM, Cosme M, Kisiala AB, Mulholland S, Said ZMF, Spíchal L, Emery RJN, Declerck S, Guinel FC. A Stimulatory Role for Cytokinin in the Arbuscular Mycorrhizal Symbiosis of Pea. FRONTIERS IN PLANT SCIENCE 2019; 10:262. [PMID: 30915091 PMCID: PMC6423060 DOI: 10.3389/fpls.2019.00262] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 02/19/2019] [Indexed: 05/03/2023]
Abstract
The arbuscular mycorrhizal (AM) symbiosis between terrestrial plants and AM fungi is regulated by plant hormones. For most of these, a role has been clearly assigned in this mutualistic interaction; however, there are still contradictory reports for cytokinin (CK). Here, pea plants, the wild type (WT) cv. Sparkle and its mutant E151 (Pssym15), were inoculated with the AM fungus Rhizophagus irregularis. E151 has previously been characterized as possessing high CK levels in non-mycorrhizal (myc-) roots and exhibiting high number of fungal structures in mycorrhizal (myc+) roots. Myc- and myc+ plants were treated 7, 9, and 11 days after inoculation (DAI) with synthetic compounds known to alter CK status. WT plants were treated with a synthetic CK [6-benzylaminopurine (BAP)] or the CK degradation inhibitor INCYDE, whereas E151 plants were treated with the CK receptor antagonist PI-55. At 13 DAI, plant CK content was analyzed by mass spectrometry. The effects of the synthetic compounds on AM colonization were assessed at 28 (WT) or 35 (E151) DAI via a modified magnified intersections method. The only noticeable difference seen between myc- and myc+ plants in terms of CK content was in the levels of nucleotides (NTs). Whereas WT plants responded to fungi by lowering their NT levels, E151 plants did not. Since NTs are thought to be converted into active CK forms, this result suggests that active CKs were synthesized more effectively in WT than in E151. In general, myc+ and myc- WT plants responded similarly to INCYDE by lowering significantly their NT levels and increasing slightly their active CK levels; these responses were less obvious in BAP-treated WT plants. In contrast, the response of E151 plants to PI-55 depended on the plant mycorrhizal status. Whereas treated myc- plants exhibited high NT and low active CK levels, treated myc+ plants displayed low levels of both NTs and active CKs. Moreover, treated WT plants were more colonized than treated E151 plants. We concluded that CKs have a stimulatory role in AM colonization because increased active CK levels were paralleled with increased AM colonization while decreased CK levels corresponded to reduced AM colonization.
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Affiliation(s)
- Dane M. Goh
- Biology, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Marco Cosme
- Mycology, Applied Microbiology, Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | | | | | | | - Lukáš Spíchal
- Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University Olomouc, Olomouc, Czechia
| | | | - Stéphane Declerck
- Mycology, Applied Microbiology, Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgium
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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: 61] [Impact Index Per Article: 10.2] [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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Nisler J, Kopečný D, Končitíková R, Zatloukal M, Bazgier V, Berka K, Zalabák D, Briozzo P, Strnad M, Spíchal L. Novel thidiazuron-derived inhibitors of cytokinin oxidase/dehydrogenase. PLANT MOLECULAR BIOLOGY 2016; 92:235-48. [PMID: 27422623 DOI: 10.1007/s11103-016-0509-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 06/29/2016] [Indexed: 05/11/2023]
Abstract
Two new TDZ derivatives (HETDZ and 3FMTDZ) are very potent inhibitors of CKX and are promising candidates for in vivo studies. Cytokinin hormones regulate a wide range of essential processes in plants. Thidiazuron (N-phenyl-N'-1,2,3-thiadiazol-5-yl urea, TDZ), formerly registered as a cotton defoliant, is a well known inhibitor of cytokinin oxidase/dehydrogenase (CKX), an enzyme catalyzing the degradation of cytokinins. TDZ thus increases the lifetime of cytokinins and their effects in plants. We used in silico modeling to design, synthesize and characterize twenty new TDZ derivatives with improved inhibitory properties. Two compounds, namely 1-[1,2,3]thiadiazol-5-yl-3-(3-trifluoromethoxy-phenyl)urea (3FMTDZ) and 1-[2-(2-hydroxyethyl)phenyl]-3-(1,2,3-thiadiazol-5-yl)urea (HETDZ), displayed up to 15-fold lower IC 50 values compared with TDZ for AtCKX2 from Arabidopsis thaliana and ZmCKX1 and ZmCKX4a from Zea mays. Binding modes of 3FMTDZ and HETDZ were analyzed by X-ray crystallography. Crystal structure complexes, solved at 2.0 Å resolution, revealed that HETDZ and 3FMTDZ bound differently in the active site of ZmCKX4a: the thiadiazolyl ring of 3FMTDZ was positioned over the isoalloxazine ring of FAD, whereas that of HETDZ had the opposite orientation, pointing toward the entrance of the active site. The compounds were further tested for cytokinin activity in several cytokinin bioassays. We suggest that the combination of simple synthesis, lowered cytokinin activity, and enhanced inhibitory effects on CKX isoforms, makes 3FMTDZ and HETDZ suitable candidates for in vivo studies.
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Affiliation(s)
- Jaroslav Nisler
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research (CRH), Institute of Experimental Botany AS CR, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic.
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic.
- Department of Chemistry of Natural Compounds, Faculty of Food and Biochemical Technology, University of Chemistry and Technology in Prague, Technická 5, 166 28, Prague, Czech Republic.
| | - David Kopečný
- Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic.
| | - Radka Končitíková
- Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
| | - Marek Zatloukal
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research (CRH), Institute of Experimental Botany AS CR, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
| | - Václav Bazgier
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research (CRH), Institute of Experimental Botany AS CR, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
- Department of Physical Chemistry, Faculty of Science, Palacký University, 17. listopadu 1192/12, 771 46, Olomouc, Czech Republic
| | - Karel Berka
- Department of Physical Chemistry, Faculty of Science, Palacký University, 17. listopadu 1192/12, 771 46, Olomouc, Czech Republic
- Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacký University, 17. listopadu 1192/12, 771 46, Olomouc, Czech Republic
| | - David Zalabák
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
| | - Pierre Briozzo
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, Université Paris-Saclay, 78026, Versailles, France
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research (CRH), Institute of Experimental Botany AS CR, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
| | - Lukáš Spíchal
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research (CRH), Institute of Experimental Botany AS CR, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
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Plíhalová L, Vylíčilová H, Doležal K, Zahajská L, Zatloukal M, Strnad M. Synthesis of aromatic cytokinins for plant biotechnology. N Biotechnol 2016; 33:614-624. [DOI: 10.1016/j.nbt.2015.11.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 11/11/2015] [Accepted: 11/27/2015] [Indexed: 11/25/2022]
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