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Karady M, Hladík P, Cermanová K, Jiroutová P, Antoniadi I, Casanova-Sáez R, Ljung K, Novák O. Profiling of 1-aminocyclopropane-1-carboxylic acid and selected phytohormones in Arabidopsis using liquid chromatography-tandem mass spectrometry. PLANT METHODS 2024; 20:41. [PMID: 38493175 PMCID: PMC10943774 DOI: 10.1186/s13007-024-01165-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Accepted: 02/27/2024] [Indexed: 03/18/2024]
Abstract
BACKGROUND Gaseous phytohormone ethylene levels are directly influenced by the production of its immediate non-volatile precursor 1-aminocyclopropane-1-carboxylic acid (ACC). Owing to the strongly acidic character of the ACC molecule, its quantification has been difficult to perform. Here, we present a simple and straightforward validated method for accurate quantification of not only ACC levels, but also major members of other important phytohormonal classes - auxins, cytokinins, jasmonic acid, abscisic acid and salicylic acid from the same biological sample. RESULTS The presented technique facilitates the analysis of 15 compounds by liquid chromatography coupled with tandem mass spectrometry. It was optimized and validated for 10 mg of fresh weight plant material. The extraction procedure is composed of a minimal amount of necessary steps. Accuracy and precision were the basis for evaluating the method, together with process efficiency, recovery and matrix effects as validation parameters. The examined compounds comprise important groups of phytohormones, their active forms and some of their metabolites, including six cytokinins, four auxins, two jasmonates, abscisic acid, salicylic acid and 1-aminocyclopropane-1-carboxylic acid. The resulting method was used to examine their contents in selected Arabidopsis thaliana mutant lines. CONCLUSION This profiling method enables a very straightforward approach for indirect ethylene study and explores how it interacts, based on content levels, with other phytohormonal groups in plants.
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Affiliation(s)
- Michal Karady
- Laboratory of Growth Regulators, Institute of Experimental Botany, Palacký University, The Czech Academy of Sciences & Faculty of Science, Olomouc, CZ-783 71, Czechia.
| | - Pavel Hladík
- Laboratory of Growth Regulators, Institute of Experimental Botany, Palacký University, The Czech Academy of Sciences & Faculty of Science, Olomouc, CZ-783 71, Czechia
| | - Kateřina Cermanová
- Laboratory of Growth Regulators, Institute of Experimental Botany, Palacký University, The Czech Academy of Sciences & Faculty of Science, Olomouc, CZ-783 71, Czechia
| | - Petra Jiroutová
- Laboratory of Growth Regulators, Institute of Experimental Botany, Palacký University, The Czech Academy of Sciences & Faculty of Science, Olomouc, CZ-783 71, Czechia
| | - Ioanna Antoniadi
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre (UPSC), Swedish University of Agricultural Sciences, Umeå, SE-901 83, Sweden
| | - Rubén Casanova-Sáez
- Department of Plant Physiology, Umeå Plant Science Centre (UPSC), Umeå University, Umeå, SE-901 87, Sweden
| | - Karin Ljung
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre (UPSC), Swedish University of Agricultural Sciences, Umeå, SE-901 83, Sweden
| | - Ondřej Novák
- Laboratory of Growth Regulators, Institute of Experimental Botany, Palacký University, The Czech Academy of Sciences & Faculty of Science, Olomouc, CZ-783 71, Czechia
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre (UPSC), Swedish University of Agricultural Sciences, Umeå, SE-901 83, Sweden
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Jiang X, Lai S, Kong D, Hou X, Shi Y, Fu Z, Liu Y, Gao L, Xia T. Al-induced CsUGT84J2 enhances flavonol and auxin accumulation to promote root growth in tea plants. HORTICULTURE RESEARCH 2023; 10:uhad095. [PMID: 37350798 PMCID: PMC10282599 DOI: 10.1093/hr/uhad095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 04/25/2023] [Indexed: 06/24/2023]
Abstract
Although Al is not necessary or even toxic to most plants, it is beneficial for the growth of tea plants. However, the mechanism through which Al promotes root growth in tea plants remains unclear. In the present study, we found that flavonol glycoside levels in tea roots increased following Al treatment, and the Al-induced UDP glycosyltransferase CsUGT84J2 was involved in this mechanism. Enzyme activity assays revealed that rCsUGT84J2 exhibited catalytic activity on multiple types of substrates, including phenolic acids, flavonols, and auxins in vitro. Furthermore, metabolic analysis with UPLC-QqQ-MS/MS revealed significantly increased flavonol and auxin glycoside accumulation in CsUGT84J2-overexpressing Arabidopsis thaliana. In addition, the expression of genes involved in the flavonol pathway as well as in the auxin metabolism, transport, and signaling pathways was remarkably enhanced. Additionally, lateral root growth and exogenous Al stress tolerance were significantly improved in transgenic A. thaliana. Moreover, gene expression and metabolic accumulation related to phenolic acids, flavonols, and auxin were upregulated in CsUGT84J2-overexpressing tea plants but downregulated in CsUGT84J2-silenced tea plants. In conclusion, Al treatment induced CsUGT84J2 expression, mediated flavonol and auxin glycosylation, and regulated endogenous auxin homeostasis in tea roots, thereby promoting the growth of tea plants. Our findings lay the foundation for studying the precise mechanisms through which Al promotes the growth of tea plants.
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Affiliation(s)
| | | | - Dexu Kong
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui, China
| | - Xiaohan Hou
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui, China
| | - Yufeng Shi
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui, China
| | - Zhouping Fu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui, China
| | - Yajun Liu
- School of Life Science, Anhui Agricultural University, Hefei, Anhui, China
| | | | - Tao Xia
- Corresponding author: E-mail:
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Brunoni F, Pěnčík A, Žukauskaitė A, Ament A, Kopečná M, Collani S, Kopečný D, Novák O. Amino acid conjugation of oxIAA is a secondary metabolic regulation involved in auxin homeostasis. THE NEW PHYTOLOGIST 2023; 238:2264-2270. [PMID: 36941219 DOI: 10.1111/nph.18887] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Accepted: 03/11/2023] [Indexed: 05/19/2023]
Affiliation(s)
- Federica Brunoni
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, Faculty of Science of Palacký University, Olomouc, CZ-78371, Czech Republic
| | - Aleš Pěnčík
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, Faculty of Science of Palacký University, Olomouc, CZ-78371, Czech Republic
| | - Asta Žukauskaitė
- Department of Chemical Biology, Faculty of Science, Palacký University, Olomouc, CZ-78371, Czech Republic
| | - Anita Ament
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, Faculty of Science of Palacký University, Olomouc, CZ-78371, Czech Republic
| | - Martina Kopečná
- Department of Experimental Biology, Faculty of Science, Palacký University, Olomouc, CZ-78371, Czech Republic
| | - Silvio Collani
- Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, Umeå, SE-90736, Sweden
| | - David Kopečný
- Department of Experimental Biology, Faculty of Science, Palacký University, Olomouc, CZ-78371, Czech Republic
| | - Ondřej Novák
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, Faculty of Science of Palacký University, Olomouc, CZ-78371, Czech Republic
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4
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Široká J, Brunoni F, Pěnčík A, Mik V, Žukauskaitė A, Strnad M, Novák O, Floková K. High-throughput interspecies profiling of acidic plant hormones using miniaturised sample processing. PLANT METHODS 2022; 18:122. [PMID: 36384566 PMCID: PMC9670418 DOI: 10.1186/s13007-022-00954-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 10/20/2022] [Indexed: 05/12/2023]
Abstract
BACKGROUND Acidic phytohormones are small molecules controlling many physiological functions in plants. A comprehensive picture of their profiles including the active forms, precursors and metabolites provides an important insight into ongoing physiological processes and is essential for many biological studies performed on plants. RESULTS A high-throughput sample preparation method for liquid chromatography-tandem mass spectrometry determination of 25 acidic phytohormones classed as auxins, jasmonates, abscisates and salicylic acid was optimised. The method uses a small amount of plant tissue (less than 10 mg fresh weight) and acidic extraction in 1 mol/L formic acid in 10% aqueous methanol followed by miniaturised purification on reverse phase sorbent accommodated in pipette tips organised in a 3D printed 96-place interface, capable of processing 192 samples in one run. The method was evaluated in terms of process efficiency, recovery and matrix effects as well as establishing validation parameters such as accuracy and precision. The applicability of the method in relation to the amounts of sample collected from distantly related plant species was evaluated and the results for phytohormone profiles are discussed in the context of literature reports. CONCLUSION The method developed enables high-throughput profiling of acidic phytohormones with minute amounts of plant material, and it is suitable for large scale interspecies studies.
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Affiliation(s)
- Jitka Široká
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences & Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic.
| | - Federica Brunoni
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences & Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Aleš Pěnčík
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences & Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Václav Mik
- Department of Experimental Biology, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Asta Žukauskaitė
- Department of Chemical Biology, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences & Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Ondřej Novák
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences & Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Kristýna Floková
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences & Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
- Plant Hormone Biology Group, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
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Casanova‐Sáez R, Mateo‐Bonmatí E, Šimura J, Pěnčík A, Novák O, Staswick P, Ljung K. Inactivation of the entire Arabidopsis group II GH3s confers tolerance to salinity and water deficit. THE NEW PHYTOLOGIST 2022; 235:263-275. [PMID: 35322877 PMCID: PMC9322293 DOI: 10.1111/nph.18114] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Accepted: 03/05/2022] [Indexed: 05/25/2023]
Abstract
Indole-3-acetic acid (IAA) controls a plethora of developmental processes. Thus, regulation of its concentration is of great relevance for plant performance. Cellular IAA concentration depends on its transport, biosynthesis and the various pathways for IAA inactivation, including oxidation and conjugation. Group II members of the GRETCHEN HAGEN 3 (GH3) gene family code for acyl acid amido synthetases catalysing the conjugation of IAA to amino acids. However, the high degree of functional redundancy among them has hampered thorough analysis of their roles in plant development. In this work, we generated an Arabidopsis gh3.1,2,3,4,5,6,9,17 (gh3oct) mutant to knock out the group II GH3 pathway. The gh3oct plants had an elaborated root architecture, showed an increased tolerance to different osmotic stresses, including an IAA-dependent tolerance to salinity, and were more tolerant to water deficit. Indole-3-acetic acid metabolite quantification in gh3oct plants suggested the existence of additional GH3-like enzymes in IAA metabolism. Moreover, our data suggested that 2-oxindole-3-acetic acid production depends, at least in part, on the GH3 pathway. Targeted stress-hormone analysis further suggested involvement of abscisic acid in the differential response to salinity of gh3oct plants. Taken together, our data provide new insights into the roles of group II GH3s in IAA metabolism and hormone-regulated plant development.
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Affiliation(s)
- Rubén Casanova‐Sáez
- Department of Forest Genetics and Plant PhysiologyUmeå Plant Science Centre (UPSC)Swedish University of Agricultural Sciences901 83UmeåSweden
| | - Eduardo Mateo‐Bonmatí
- Department of Forest Genetics and Plant PhysiologyUmeå Plant Science Centre (UPSC)Swedish University of Agricultural Sciences901 83UmeåSweden
| | - Jan Šimura
- Department of Forest Genetics and Plant PhysiologyUmeå Plant Science Centre (UPSC)Swedish University of Agricultural Sciences901 83UmeåSweden
| | - Aleš Pěnčík
- Laboratory of Growth RegulatorsFaculty of SciencePalacký University and Institute of Experimental Botany of the Czech Academy of SciencesŠlechtitelů 27OlomoucCzech Republic
| | - Ondřej Novák
- Department of Forest Genetics and Plant PhysiologyUmeå Plant Science Centre (UPSC)Swedish University of Agricultural Sciences901 83UmeåSweden
- Laboratory of Growth RegulatorsFaculty of SciencePalacký University and Institute of Experimental Botany of the Czech Academy of SciencesŠlechtitelů 27OlomoucCzech Republic
| | - Paul Staswick
- Department of Agronomy and HorticultureUniversity of NebraskaLincolnNEUSA
| | - Karin Ljung
- Department of Forest Genetics and Plant PhysiologyUmeå Plant Science Centre (UPSC)Swedish University of Agricultural Sciences901 83UmeåSweden
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Mateo-Bonmatí E, Casanova-Sáez R, Šimura J, Ljung K. Broadening the roles of UDP-glycosyltransferases in auxin homeostasis and plant development. THE NEW PHYTOLOGIST 2021; 232:642-654. [PMID: 34289137 DOI: 10.1111/nph.17633] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 07/03/2021] [Indexed: 05/02/2023]
Abstract
The levels of the important plant growth regulator indole-3-acetic acid (IAA) are tightly controlled within plant tissues to spatiotemporally orchestrate concentration gradients that drive plant growth and development. Metabolic inactivation of bioactive IAA is known to participate in the modulation of IAA maxima and minima. IAA can be irreversibly inactivated by oxidation and conjugation to aspartate and glutamate. Usually overlooked because of its reversible nature, the most abundant inactive IAA form is the IAA-glucose (IAA-glc) conjugate. Glycosylation of IAA in Arabidopsis thaliana is reported to be carried out by UDP-glycosyltransferase 84B1 (UGT84B1), while UGT74D1 has been implicated in the glycosylation of the irreversibly formed IAA catabolite oxIAA. Here we demonstrated that both UGT84B1 and UGT74D1 modulate IAA levels throughout plant development by dual IAA and oxIAA glycosylation. Moreover, we identified a novel UGT subfamily whose members redundantly mediate the glycosylation of oxIAA and modulate skotomorphogenic growth.
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Affiliation(s)
- Eduardo Mateo-Bonmatí
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, SE-901 83, Sweden
| | - Rubén Casanova-Sáez
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, SE-901 83, Sweden
| | - Jan Šimura
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, SE-901 83, Sweden
| | - Karin Ljung
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, SE-901 83, Sweden
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7
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Müller K, Dobrev PI, Pěnčík A, Hošek P, Vondráková Z, Filepová R, Malínská K, Brunoni F, Helusová L, Moravec T, Retzer K, Harant K, Novák O, Hoyerová K, Petrášek J. DIOXYGENASE FOR AUXIN OXIDATION 1 catalyzes the oxidation of IAA amino acid conjugates. PLANT PHYSIOLOGY 2021; 187:103-115. [PMID: 34618129 PMCID: PMC8418401 DOI: 10.1093/plphys/kiab242] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 04/29/2021] [Indexed: 05/15/2023]
Abstract
Together with auxin transport, auxin metabolism is a key determinant of auxin signaling output by plant cells. Enzymatic machinery involved in auxin metabolism is subject to regulation based on numerous inputs, including the concentration of auxin itself. Therefore, experiments characterizing altered auxin availability and subsequent changes in auxin metabolism could elucidate the function and regulatory role of individual elements in the auxin metabolic machinery. Here, we studied auxin metabolism in auxin-dependent tobacco BY-2 cells. We revealed that the concentration of N-(2-oxindole-3-acetyl)-l-aspartic acid (oxIAA-Asp), the most abundant auxin metabolite produced in the control culture, dramatically decreased in auxin-starved BY-2 cells. Analysis of the transcriptome and proteome in auxin-starved cells uncovered significant downregulation of all tobacco (Nicotiana tabacum) homologs of Arabidopsis (Arabidopsis thaliana) DIOXYGENASE FOR AUXIN OXIDATION 1 (DAO1), at both transcript and protein levels. Auxin metabolism profiling in BY-2 mutants carrying either siRNA-silenced or CRISPR-Cas9-mutated NtDAO1, as well as in dao1-1 Arabidopsis plants, showed not only the expected lower levels of oxIAA, but also significantly lower abundance of oxIAA-Asp. Finally, ability of DAO1 to oxidize IAA-Asp was confirmed by an enzyme assay in AtDAO1-producing bacterial culture. Our results thus represent direct evidence of DAO1 activity on IAA amino acid conjugates.
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Affiliation(s)
- Karel Müller
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Praha 6, Czech Republic
| | - Petre Ivanov Dobrev
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Praha 6, Czech Republic
| | - Aleš Pěnčík
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, and Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Petr Hošek
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Praha 6, Czech Republic
| | - Zuzana Vondráková
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Praha 6, Czech Republic
| | - Roberta Filepová
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Praha 6, Czech Republic
| | - Kateřina Malínská
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Praha 6, Czech Republic
| | - Federica Brunoni
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, and Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Lenka Helusová
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Praha 6, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 128 44 Prague 2, Czech Republic
| | - Tomáš Moravec
- Laboratory of Virology, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Praha 6, Czech Republic
| | - Katarzyna Retzer
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Praha 6, Czech Republic
| | - Karel Harant
- Proteomics Core Facility, Faculty of Science, Charles University, BIOCEV, Průmyslová 595, Vestec 252 42, Czech Republic
| | - Ondřej Novák
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, and Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Klára Hoyerová
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Praha 6, Czech Republic
| | - Jan Petrášek
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Praha 6, Czech Republic
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Brunoni F, Collani S, Casanova-Sáez R, Šimura J, Karady M, Schmid M, Ljung K, Bellini C. Conifers exhibit a characteristic inactivation of auxin to maintain tissue homeostasis. THE NEW PHYTOLOGIST 2020; 226:1753-1765. [PMID: 32004385 DOI: 10.1111/nph.16463] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 01/27/2020] [Indexed: 06/10/2023]
Abstract
Dynamic regulation of the concentration of the natural auxin (IAA) is essential to coordinate most of the physiological and developmental processes and responses to environmental changes. Oxidation of IAA is a major pathway to control auxin concentrations in angiosperms and, along with IAA conjugation, to respond to perturbation of IAA homeostasis. However, these regulatory mechanisms remain poorly investigated in conifers. To reduce this knowledge gap, we investigated the different contributions of the IAA inactivation pathways in conifers. MS-based quantification of IAA metabolites under steady-state conditions and after perturbation was investigated to evaluate IAA homeostasis in conifers. Putative Picea abies GH3 genes (PaGH3) were identified based on a comprehensive phylogenetic analysis including angiosperms and basal land plants. Auxin-inducible PaGH3 genes were identified by expression analysis and their IAA-conjugating activity was explored. Compared to Arabidopsis, oxidative and conjugative pathways differentially contribute to reduce IAA concentrations in conifers. We demonstrated that the oxidation pathway plays a marginal role in controlling IAA homeostasis in spruce. By contrast, an excess of IAA rapidly activates GH3-mediated irreversible conjugation pathways. Taken together, these data indicate that a diversification of IAA inactivation mechanisms evolved specifically in conifers.
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Affiliation(s)
- Federica Brunoni
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University (Umu), 90736, Umeå, Sweden
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences (SLU), 90183, Umeå, Sweden
- Laboratory of Growth Regulators, Faculty of Science, Palacký University & Institute of Experimental Botany, The Czech Academy of Sciences, Šlechtitelů 27, CZ-78371, Olomouc, Czech Republic
| | - Silvio Collani
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University (Umu), 90736, Umeå, Sweden
| | - Rubén Casanova-Sáez
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences (SLU), 90183, Umeå, Sweden
| | - Jan Šimura
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences (SLU), 90183, Umeå, Sweden
| | - Michal Karady
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences (SLU), 90183, Umeå, Sweden
- Departmebt of Chemical Biology and Genetics, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, CZ-78371, Olomouc, Czech Republic
| | - Markus Schmid
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University (Umu), 90736, Umeå, Sweden
| | - Karin Ljung
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences (SLU), 90183, Umeå, Sweden
| | - Catherine Bellini
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University (Umu), 90736, Umeå, Sweden
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
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