1
|
Cohen JD, Strader LC. An auxin research odyssey: 1989-2023. THE PLANT CELL 2024; 36:1410-1428. [PMID: 38382088 PMCID: PMC11062468 DOI: 10.1093/plcell/koae054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 01/23/2024] [Accepted: 02/07/2024] [Indexed: 02/23/2024]
Abstract
The phytohormone auxin is at times called the master regulator of plant processes and has been shown to be a central player in embryo development, the establishment of the polar axis, early aspects of seedling growth, as well as growth and organ formation during later stages of plant development. The Plant Cell has been key, since the inception of the journal, to developing an understanding of auxin biology. Auxin-regulated plant growth control is accomplished by both changes in the levels of active hormones and the sensitivity of plant tissues to these concentration changes. In this historical review, we chart auxin research as it has progressed in key areas and highlight the role The Plant Cell played in these scientific developments. We focus on understanding auxin-responsive genes, transcription factors, reporter constructs, perception, and signal transduction processes. Auxin metabolism is discussed from the development of tryptophan auxotrophic mutants, the molecular biology of conjugate formation and hydrolysis, indole-3-butyric acid metabolism and transport, and key steps in indole-3-acetic acid biosynthesis, catabolism, and transport. This progress leads to an expectation of a more comprehensive understanding of the systems biology of auxin and the spatial and temporal regulation of cellular growth and development.
Collapse
Affiliation(s)
- Jerry D Cohen
- Department of Horticultural Science and the Microbial and Plant Genomics Institute, University of Minnesota, Saint Paul, MN 55108, USA
| | - Lucia C Strader
- Department of Biology, Duke University, Durham, NC 27008, USA
| |
Collapse
|
2
|
Gélinas-Marion A, Eléouët MP, Cook SD, Vander Schoor JK, Abel SAG, Nichols DS, Smith JA, Hofer JMI, Ross JJ. Plant Development in the Garden Pea as Revealed by Mutations in the Crd/PsYUC1 Gene. Genes (Basel) 2023; 14:2115. [PMID: 38136938 PMCID: PMC10742580 DOI: 10.3390/genes14122115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/28/2023] [Accepted: 11/17/2023] [Indexed: 12/24/2023] Open
Abstract
In common with other plant species, the garden pea (Pisum sativum) produces the auxin indole-3-acetic acid (IAA) from tryptophan via a single intermediate, indole-3-pyruvic acid (IPyA). IPyA is converted to IAA by PsYUC1, also known as Crispoid (Crd). Here, we extend our understanding of the developmental processes affected by the Crd gene by examining the phenotypic effects of crd gene mutations on leaves, flowers, and roots. We show that in pea, Crd/PsYUC1 is important for the initiation and identity of leaflets and tendrils, stamens, and lateral roots. We also report on aspects of auxin deactivation in pea.
Collapse
Affiliation(s)
- Ariane Gélinas-Marion
- School of Natural Sciences, University of Tasmania, Sandy Bay, Hobart 7001, Australia; (A.G.-M.); (J.K.V.S.); (S.A.G.A.); (J.A.S.)
| | - Morgane P. Eléouët
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Plas Gogerddan, Aberystwyth SY23 3EE, UK;
| | - Sam D. Cook
- Department of Chemistry, Umea University, Linnaeus vag 10, Kemi A3, 901 87 Umea, Sweden;
| | - Jacqueline K. Vander Schoor
- School of Natural Sciences, University of Tasmania, Sandy Bay, Hobart 7001, Australia; (A.G.-M.); (J.K.V.S.); (S.A.G.A.); (J.A.S.)
| | - Steven A. G. Abel
- School of Natural Sciences, University of Tasmania, Sandy Bay, Hobart 7001, Australia; (A.G.-M.); (J.K.V.S.); (S.A.G.A.); (J.A.S.)
| | - David S. Nichols
- Central Science Laboratory, University of Tasmania, Sandy Bay, Hobart 7001, Australia;
| | - Jason A. Smith
- School of Natural Sciences, University of Tasmania, Sandy Bay, Hobart 7001, Australia; (A.G.-M.); (J.K.V.S.); (S.A.G.A.); (J.A.S.)
| | - Julie M. I. Hofer
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Plas Gogerddan, Aberystwyth SY23 3EE, UK;
| | - John J. Ross
- School of Natural Sciences, University of Tasmania, Sandy Bay, Hobart 7001, Australia; (A.G.-M.); (J.K.V.S.); (S.A.G.A.); (J.A.S.)
| |
Collapse
|
3
|
Solanki M, Shukla LI. Recent advances in auxin biosynthesis and homeostasis. 3 Biotech 2023; 13:290. [PMID: 37547917 PMCID: PMC10400529 DOI: 10.1007/s13205-023-03709-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 07/18/2023] [Indexed: 08/08/2023] Open
Abstract
The plant proliferation is linked with auxins which in turn play a pivotal role in the rate of growth. Also, auxin concentrations could provide insights into the age, stress, and events leading to flowering and fruiting in the sessile plant kingdom. The role in rejuvenation and plasticity is now evidenced. Interest in plant auxins spans many decades, information from different plant families for auxin concentrations, transcriptional, and epigenetic evidences for gene regulation is evaluated here, for getting an insight into pattern of auxin biosynthesis. This biosynthesis takes place via an tryptophan-independent and tryptophan-dependent pathway. The independent pathway initiated before the tryptophan (trp) production involves indole as the primary substrate. On the other hand, the trp-dependent IAA pathway passes through the indole pyruvic acid (IPyA), indole-3-acetaldoxime (IAOx), and indole acetamide (IAM) pathways. Investigations on trp-dependent pathways involved mutants, namely yucca (1-11), taa1, nit1, cyp79b and cyp79b2, vt2 and crd, and independent mutants of tryptophan, ins are compiled here. The auxin conjugates of the IAA amide and ester-linked mutant gh3, iar, ilr, ill, iamt1, ugt, and dao are remarkable and could facilitate the assimilation of auxins. Efforts are made herein to provide an up-to-date detailed information about biosynthesis leading to plant sustenance. The vast information about auxin biosynthesis and homeostasis is consolidated in this review with a simplified model of auxin biosynthesis with keys and clues for important missing links since auxins can enable the plants to proliferate and override the environmental influence and needs to be probed for applications in sustainable agriculture. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-023-03709-6.
Collapse
Affiliation(s)
- Manish Solanki
- Department of Biotechnology, School of Life Sciences, Pondicherry University, Kalapet, Pondicherry, 605014 India
- Puducherry, India
| | - Lata Israni Shukla
- Department of Biotechnology, School of Life Sciences, Pondicherry University, Kalapet, Pondicherry, 605014 India
| |
Collapse
|
4
|
Hladík P, Petřík I, Žukauskaitė A, Novák O, Pěnčík A. Metabolic profiles of 2-oxindole-3-acetyl-amino acid conjugates differ in various plant species. FRONTIERS IN PLANT SCIENCE 2023; 14:1217421. [PMID: 37534287 PMCID: PMC10390838 DOI: 10.3389/fpls.2023.1217421] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 06/28/2023] [Indexed: 08/04/2023]
Abstract
Auxins are a group of phytohormones that play a key role in plant growth and development, mainly presented by the major member of the family - indole-3-acetic acid (IAA). The levels of free IAA are regulated, in addition to de novo biosynthesis, by irreversible oxidative catabolism and reversible conjugation with sugars and amino acids. These conjugates, which serve as inactive storage forms of auxin and/or degradation intermediates, can also be oxidized to form 2-oxindole-3-acetyl-1-O-ß-d-glucose (oxIAA-glc) and oxIAA-amino acids (oxIAA-AAs). Until now, only oxIAA conjugates with aspartate and glutamate have been identified in plants. However, detailed information on the endogenous levels of these and other putative oxIAA-amino acid conjugates in various plant species and their spatial distribution is still not well understood but is finally getting more attention. Herein, we identified and characterized two novel naturally occurring auxin metabolites in plants, namely oxIAA-leucine (oxIAA-Leu) and oxIAA-phenylalanine (oxIAA-Phe). Subsequently, a new liquid chromatography-tandem mass spectrometry method was developed for the determination of a wide range of IAA metabolites. Using this methodology, the quantitative determination of IAA metabolites including newly characterized oxIAA conjugates in roots, shoots and cotyledons of four selected plant models - Arabidopsis thaliana, pea (Pisum sativum L.), wheat (Triticum aestivum L.) and maize (Zea mays L.) was performed to compare auxin metabolite profiles. The distribution of various groups of auxin metabolites differed notably among the studied species as well as their sections. For example, oxIAA-AA conjugates were the major metabolites found in pea, while oxIAA-glc dominated in Arabidopsis. We further compared IAA metabolite levels in plants harvested at different growth stages to monitor the dynamics of IAA metabolite profiles during early seedling development. In general, our results show a great diversity of auxin inactivation pathways among angiosperm plants. We believe that our findings will greatly contribute to a better understanding of IAA homeostasis.
Collapse
Affiliation(s)
- Pavel Hladík
- Laboratory of Growth Regulators, Institute of Experimental Botany, The Czech Academy of Sciences & Faculty of Science, Palacký University, Olomouc, Czechia
| | - Ivan Petřík
- Laboratory of Growth Regulators, Institute of Experimental Botany, The Czech Academy of Sciences & Faculty of Science, Palacký University, Olomouc, Czechia
| | - Asta Žukauskaitė
- Department of Chemical Biology, Faculty of Science, Palacký University, Olomouc, Czechia
| | - Ondřej Novák
- Laboratory of Growth Regulators, Institute of Experimental Botany, The Czech Academy of Sciences & Faculty of Science, Palacký University, Olomouc, Czechia
| | - Aleš Pěnčík
- Laboratory of Growth Regulators, Institute of Experimental Botany, The Czech Academy of Sciences & Faculty of Science, Palacký University, Olomouc, Czechia
| |
Collapse
|
5
|
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.
Collapse
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
| |
Collapse
|
6
|
Sipari N, Lihavainen J, Keinänen M. Metabolite Profiling of Paraquat Tolerant Arabidopsis thaliana Radical-induced Cell Death1 ( rcd1)-A Mediator of Antioxidant Defence Mechanisms. Antioxidants (Basel) 2022; 11:antiox11102034. [PMID: 36290757 PMCID: PMC9598866 DOI: 10.3390/antiox11102034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 10/06/2022] [Accepted: 10/13/2022] [Indexed: 11/16/2022] Open
Abstract
RADICAL-INDUCED CELL DEATH1 (RCD1) is an Arabidopsis thaliana nuclear protein that is disrupted during oxidative stress. RCD1 is considered an important integrative node in development and stress responses, and the rcd1 plants have several phenotypes and altered resistance to a variety of abiotic and biotic stresses. One of the phenotypes of rcd1 is resistance to the herbicide paraquat, but the mechanisms behind it are unknown. Paraquat causes a rapid burst of reactive oxygen species (ROS) initially in the chloroplast. We performed multi-platform metabolomic analyses in wild type Col-0 and paraquat resistant rcd1 plants to identify pathways conveying resistance and the function of RCD1 in this respect. Wild type and rcd1 plants were clearly distinguished by their abundance of antioxidants and specialized metabolites and their responses to paraquat. The lack of response in rcd1 suggested constitutively active defense against ROS via elevated flavonoid, glutathione, β-carotene, and tocopherol levels, whereas its ascorbic acid levels were compromised under non-stressed control conditions when compared to Col-0. We propose that RCD1 acts as a hub that maintains basal antioxidant system, and its inactivation induces defense responses by enhancing the biosynthesis and redox cycling of low molecular weight antioxidants and specialized metabolites with profound antioxidant activities alleviating oxidative stress.
Collapse
Affiliation(s)
- Nina Sipari
- Viikki Metabolomics Unit, Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, P.O. Box 65, FI-00014 Helsinki, Finland
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland
- Correspondence: (N.S.); (M.K.)
| | - Jenna Lihavainen
- Umeå Plant Science Center, Department of Plant Physiology, Umeå Universitet, 90 187 Umeå, Sweden
| | - Markku Keinänen
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland
- Institute of Photonics, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland
- Correspondence: (N.S.); (M.K.)
| |
Collapse
|
7
|
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.
Collapse
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
| |
Collapse
|
8
|
Auxin Metabolome Profiling in the Arabidopsis Endoplasmic Reticulum Using an Optimised Organelle Isolation Protocol. Int J Mol Sci 2021; 22:ijms22179370. [PMID: 34502279 PMCID: PMC8431077 DOI: 10.3390/ijms22179370] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 08/20/2021] [Accepted: 08/25/2021] [Indexed: 11/17/2022] Open
Abstract
The endoplasmic reticulum (ER) is an extensive network of intracellular membranes. Its major functions include proteosynthesis, protein folding, post-transcriptional modification and sorting of proteins within the cell, and lipid anabolism. Moreover, several studies have suggested that it may be involved in regulating intracellular auxin homeostasis in plants by modulating its metabolism. Therefore, to study auxin metabolome in the ER, it is necessary to obtain a highly enriched (ideally, pure) ER fraction. Isolation of the ER is challenging because its biochemical properties are very similar to those of other cellular endomembranes. Most published protocols for ER isolation use density gradient ultracentrifugation, despite its suboptimal resolving power. Here we present an optimised protocol for ER isolation from Arabidopsis thaliana seedlings for the subsequent mass spectrometric determination of ER-specific auxin metabolite profiles. Auxin metabolite analysis revealed highly elevated levels of active auxin form (IAA) within the ER compared to whole plants. Moreover, samples prepared using our optimised isolation ER protocol are amenable to analysis using various “omics” technologies including analyses of both macromolecular and low molecular weight compounds from the same sample.
Collapse
|
9
|
Cu(II) complex with auxin (3-indoleacetic acid) and an aromatic planar ligand: synthesis, crystal structure, biomolecular interactions and radical scavenging activity. EUROPEAN BIOPHYSICS JOURNAL : EBJ 2021; 50:771-785. [PMID: 33929571 DOI: 10.1007/s00249-021-01525-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/26/2020] [Accepted: 03/25/2021] [Indexed: 10/21/2022]
Abstract
A novel water soluble ternary copper(II) complex,-[Cu2(phen)2(3-IAA)2(H2O)](ClO4)2·H2O-(phen: 1,10-phenanthroline, 3-IAA: 3-indoleacetic acid), has been synthesized and characterized by elemental CHN analysis, ESI-TOF, FTIR and single-crystal X-ray diffraction techniques. Interaction of the complex with calf thymus DNA (CT-DNA) has been investigated by absorption spectral titration, ethidium bromide (EB) and Hoechst 33258 displacement assay. The interactions between the complex and bovine serum albumin (BSA) were investigated by electronic absorption and fluorescence spectroscopy methods. The experimental results indicate that the fluorescence quenching mechanism between the complex and BSA is a static quenching process. The Stern-Volmer constants, binding constants, binding sites and the corresponding thermodynamic parameters (ΔG, ΔH, ΔS) of BSA + complex systems were determined at different temperatures. The binding distance between the complex and BSA was calculated according to Förster non-radiation energy transfer theory (FRET). The effect of the complex on the conformation of BSA was also examined using synchronous, two dimensional (2D) and three dimensional (3D) fluorescence spectroscopy. Furthermore, the oxygen radical scavenging activity of the complex was determined in terms of IC50, using the DPPH and H2O2 method, to show that it particularly enables electron loss from radical species. This study highlights the importance of indole and moieties in the development of antioxidant agents. A potent drug candidate novel water soluble ternary copper(II) complex,-[Cu2(phen)2(3-IAA)2(H2O)] (ClO4)2·H2O-(phen: 1,10-phenanthroline, 3-IAA: 3-indoleacetic acid), has been synthesized and characterized by elemental CHN analysis, FTIR, ESI-MS and single-crystal X-ray diffraction techniques. The complex has been tested for in vitro biomacromolecular interactions by spectroscopic methods. Furthermore, radical scavenging activities of the complex were also investigated.
Collapse
|
10
|
Cytokinin-Controlled Gradient Distribution of Auxin in Arabidopsis Root Tip. Int J Mol Sci 2021; 22:ijms22083874. [PMID: 33918090 PMCID: PMC8069370 DOI: 10.3390/ijms22083874] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/04/2021] [Accepted: 04/06/2021] [Indexed: 01/21/2023] Open
Abstract
The plant root is a dynamic system, which is able to respond promptly to external environmental stimuli by constantly adjusting its growth and development. A key component regulating this growth and development is the finely tuned cross-talk between the auxin and cytokinin phytohormones. The gradient distribution of auxin is not only important for the growth and development of roots, but also for root growth in various response. Recent studies have shed light on the molecular mechanisms of cytokinin-mediated regulation of local auxin biosynthesis/metabolism and redistribution in establishing active auxin gradients, resulting in cell division and differentiation in primary root tips. In this review, we focus our attention on the molecular mechanisms underlying the cytokinin-controlled auxin gradient in root tips.
Collapse
|
11
|
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.
Collapse
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
| |
Collapse
|
12
|
Sun L, Feraru E, Feraru MI, Waidmann S, Wang W, Passaia G, Wang ZY, Wabnik K, Kleine-Vehn J. PIN-LIKES Coordinate Brassinosteroid Signaling with Nuclear Auxin Input in Arabidopsis thaliana. Curr Biol 2020; 30:1579-1588.e6. [PMID: 32169207 PMCID: PMC7198975 DOI: 10.1016/j.cub.2020.02.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 12/12/2019] [Accepted: 02/03/2020] [Indexed: 11/15/2022]
Abstract
Auxin and brassinosteroids (BR) are crucial growth regulators and display overlapping functions during plant development. Here, we reveal an alternative phytohormone crosstalk mechanism, revealing that BR signaling controls PIN-LIKES (PILS)-dependent nuclear abundance of auxin. We performed a forward genetic screen for imperial pils (imp) mutants that enhance the overexpression phenotypes of PILS5 putative intracellular auxin transport facilitator. Here, we report that the imp1 mutant is defective in the BR-receptor BRASSINOSTEROID INSENSITIVE 1 (BRI1). Our set of data reveals that BR signaling transcriptionally and post-translationally represses the accumulation of PILS proteins at the endoplasmic reticulum, thereby increasing nuclear abundance and signaling of auxin. We demonstrate that this alternative phytohormonal crosstalk mechanism integrates BR signaling into auxin-dependent organ growth rates and likely has widespread importance for plant development.
Collapse
Affiliation(s)
- Lin Sun
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, Vienna 1190, Austria
| | - Elena Feraru
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, Vienna 1190, Austria
| | - Mugurel I Feraru
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, Vienna 1190, Austria
| | - Sascha Waidmann
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, Vienna 1190, Austria
| | - Wenfei Wang
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA; Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, College of Life Sciences, Fujian Agriculture and Forestry University (FAFU), Fuzhou 350002, China
| | - Gisele Passaia
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA
| | - Zhi-Yong Wang
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA
| | - Krzysztof Wabnik
- Centro de Biotecnología y Genómica de Plantas (CBGP, UPM-INIA) Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo-UPM, 28223 Pozuelo de Alarcón, Madrid, Spain
| | - Jürgen Kleine-Vehn
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, Vienna 1190, Austria.
| |
Collapse
|
13
|
Zhang C, He Q, Wang M, Gao X, Chen J, Shen C. Exogenous indole acetic acid alleviates Cd toxicity in tea (Camellia sinensis). ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 190:110090. [PMID: 31874405 DOI: 10.1016/j.ecoenv.2019.110090] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 11/12/2019] [Accepted: 12/12/2019] [Indexed: 06/10/2023]
Abstract
Cadmium (Cd), a toxic heavy metal, restrains the growth and development of plants and threatens global food safety. Many studies on the alleviation of heavy metal toxicity by exogenous phytohormones have emerged, but reports on tea (Camellia sinensis) are still scarce. In this study, the effects of indole acetic acid (IAA) (2 μM and 10 μM) on Cd uptake and on the physiological and biochemical characteristics of the 'Xiangfeicui' tea cultivar were investigated for the first time. The order of Cd accumulation in tea seedlings was root > stem > mature leaf > tender leaf. Under Cd stress (30 mg kg-1), photosynthetic pigment levels, antioxidant enzyme activity, root vigor, root IAA content, and the levels of most metabolites (including caffeine, soluble sugar, total amino acids, some amino acid components, and most catechins) were significantly reduced, while levels of malondialdehyde, proline, epicatechin, and some amino acids increased. We therefore propose that by reducing Cd accumulation, exogenous IAA can lessen the adverse effects of Cd on the physiology and biochemistry of tea seedlings, promoting the growth of healthier tea plants.
Collapse
Affiliation(s)
- Chenyu Zhang
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, Hunan, 410128, China; National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanicals, Collaborative Innovation Centre of Utilization of Functional Ingredients from Botanicals, Hunan Agricultural University, Changsha, Hunan, 410128, China.
| | - Qun He
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, Hunan, 410128, China; National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanicals, Collaborative Innovation Centre of Utilization of Functional Ingredients from Botanicals, Hunan Agricultural University, Changsha, Hunan, 410128, China
| | - Minghan Wang
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, Hunan, 410128, China; National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanicals, Collaborative Innovation Centre of Utilization of Functional Ingredients from Botanicals, Hunan Agricultural University, Changsha, Hunan, 410128, China
| | - Xizhi Gao
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, Hunan, 410128, China; National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanicals, Collaborative Innovation Centre of Utilization of Functional Ingredients from Botanicals, Hunan Agricultural University, Changsha, Hunan, 410128, China
| | - Jianjiao Chen
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, Hunan, 410128, China; National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanicals, Collaborative Innovation Centre of Utilization of Functional Ingredients from Botanicals, Hunan Agricultural University, Changsha, Hunan, 410128, China
| | - Chengwen Shen
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, Hunan, 410128, China; National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanicals, Collaborative Innovation Centre of Utilization of Functional Ingredients from Botanicals, Hunan Agricultural University, Changsha, Hunan, 410128, China.
| |
Collapse
|
14
|
The dynamic response of the Arabidopsis root metabolome to auxin and ethylene is not predicted by changes in the transcriptome. Sci Rep 2020; 10:679. [PMID: 31959762 PMCID: PMC6971091 DOI: 10.1038/s41598-019-57161-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 12/19/2019] [Indexed: 12/27/2022] Open
Abstract
While the effects of phytohormones on plant gene expression have been well characterized, comparatively little is known about how hormones influence metabolite profiles. This study examined the effects of elevated auxin and ethylene on the metabolome of Arabidopsis roots using a high-resolution 24 h time course, conducted in parallel to time-matched transcriptomic analyses. Mass spectrometry using orthogonal UPLC separation strategies (reversed phase and HILIC) in both positive and negative ionization modes was used to maximize identification of metabolites with altered levels. The findings show that the root metabolome responds rapidly to hormone stimulus and that compounds belonging to the same class of metabolites exhibit similar changes. The responses were dominated by changes in phenylpropanoid, glucosinolate, and fatty acid metabolism, although the nature and timing of the response was unique for each hormone. These alterations in the metabolome were not directly predicted by the corresponding transcriptome data, suggesting that post-transcriptional events such as changes in enzyme activity and/or transport processes drove the observed changes in the metabolome. These findings underscore the need to better understand the biochemical mechanisms underlying the temporal reconfiguration of plant metabolism, especially in relation to the hormone-metabolome interface and its subsequent physiological and morphological effects.
Collapse
|
15
|
Casanova-Sáez R, Voß U. Auxin Metabolism Controls Developmental Decisions in Land Plants. TRENDS IN PLANT SCIENCE 2019; 24:741-754. [PMID: 31230894 DOI: 10.1016/j.tplants.2019.05.006] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 05/15/2019] [Accepted: 05/20/2019] [Indexed: 05/03/2023]
Abstract
Unlike animals, whose body plans are set during embryo development, plants maintain the ability to initiate new organs throughout their life cycle. Auxin is a key regulator of almost all aspects of plant development, including morphogenesis and adaptive responses. Cellular auxin concentrations influence whether a cell will divide, grow, or differentiate, thereby contributing to organ formation, growth, and ultimately plant shape. Auxin gradients are established and maintained by a tightly regulated interplay between metabolism, signalling, and transport. Auxin is synthesised, stored, and inactivated by a multitude of parallel pathways that are all tightly regulated. Here we summarise the remarkable progress that has been achieved in identifying some key components of these pathways and the genetic complexity underlying their precise regulation.
Collapse
Affiliation(s)
- Rubén Casanova-Sáez
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden.
| | - Ute Voß
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK.
| |
Collapse
|
16
|
Skalický V, Kubeš M, Napier R, Novák O. Auxins and Cytokinins-The Role of Subcellular Organization on Homeostasis. Int J Mol Sci 2018; 19:E3115. [PMID: 30314316 PMCID: PMC6213326 DOI: 10.3390/ijms19103115] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/05/2018] [Accepted: 10/09/2018] [Indexed: 12/18/2022] Open
Abstract
Plant hormones are master regulators of plant growth and development. Better knowledge of their spatial signaling and homeostasis (transport and metabolism) on the lowest structural levels (cellular and subcellular) is therefore crucial to a better understanding of developmental processes in plants. Recent progress in phytohormone analysis at the cellular and subcellular levels has greatly improved the effectiveness of isolation protocols and the sensitivity of analytical methods. This review is mainly focused on homeostasis of two plant hormone groups, auxins and cytokinins. It will summarize and discuss their tissue- and cell-type specific distributions at the cellular and subcellular levels.
Collapse
Affiliation(s)
- Vladimír Skalický
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany of the Czech Academy of Sciences & Faculty of Science of Palacký University, Šlechtitelů 27, 78371 Olomouc, Czech Republic.
| | - Martin Kubeš
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science of Palacký University, Šlechtitelů 27, 78371 Olomouc, Czech Republic.
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK.
| | - Richard Napier
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK.
| | - Ondřej Novák
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany of the Czech Academy of Sciences & Faculty of Science of Palacký University, Šlechtitelů 27, 78371 Olomouc, Czech Republic.
| |
Collapse
|
17
|
Pěnčík A, Casanova-Sáez R, Pilařová V, Žukauskaitė A, Pinto R, Micol JL, Ljung K, Novák O. Ultra-rapid auxin metabolite profiling for high-throughput mutant screening in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:2569-2579. [PMID: 29514302 PMCID: PMC5920284 DOI: 10.1093/jxb/ery084] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 02/02/2018] [Indexed: 05/08/2023]
Abstract
Auxin (indole-3-acetic acid, IAA) plays fundamental roles as a signalling molecule during numerous plant growth and development processes. The formation of local auxin gradients and auxin maxima/minima, which is very important for these processes, is regulated by auxin metabolism (biosynthesis, degradation, and conjugation) as well as transport. When studying auxin metabolism pathways it is crucial to combine data obtained from genetic investigations with the identification and quantification of individual metabolites. Thus, to facilitate efforts to elucidate auxin metabolism and its roles in plants, we have developed a high-throughput method for simultaneously quantifying IAA and its key metabolites in minute samples (<10 mg FW) of Arabidopsis thaliana tissues by in-tip micro solid-phase extraction and fast LC-tandem MS. As a proof of concept, we applied the method to a collection of Arabidopsis mutant lines and identified lines with altered IAA metabolite profiles using multivariate data analysis. Finally, we explored the correlation between IAA metabolite profiles and IAA-related phenotypes. The developed rapid analysis of large numbers of samples (>100 samples d-1) is a valuable tool to screen for novel regulators of auxin metabolism and homeostasis among large collections of genotypes.
Collapse
Affiliation(s)
- Aleš Pěnčík
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science of Palacký University & Institute of Experimental Botany of the Czech Academy of Sciences, Šlechtitelů, Olomouc, Czech Republic
| | - Rubén Casanova-Sáez
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Veronika Pilařová
- Department of Analytical Chemistry, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Heyrovského, Hradec Králové, Czech Republic
| | - Asta Žukauskaitė
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science of Palacký University & Institute of Experimental Botany of the Czech Academy of Sciences, Šlechtitelů, Olomouc, Czech Republic
| | - Rui Pinto
- Computational Life Science Cluster (CLiC), Chemistry department (KBC), Umeå University, Umeå, Sweden
| | - José Luis Micol
- Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, Elche, Alicante, Spain
| | - Karin Ljung
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Ondřej Novák
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science of Palacký University & Institute of Experimental Botany of the Czech Academy of Sciences, Šlechtitelů, Olomouc, Czech Republic
| |
Collapse
|
18
|
Ma Q, Grones P, Robert S. Auxin signaling: a big question to be addressed by small molecules. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:313-328. [PMID: 29237069 PMCID: PMC5853230 DOI: 10.1093/jxb/erx375] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 10/16/2017] [Indexed: 05/20/2023]
Abstract
Providing a mechanistic understanding of the crucial roles of the phytohormone auxin has been an important and coherent aspect of plant biology research. Since its discovery more than a century ago, prominent advances have been made in the understanding of auxin action, ranging from metabolism and transport to cellular and transcriptional responses. However, there is a long road ahead before a thorough understanding of its complex effects is achieved, because a lot of key information is still missing. The availability of an increasing number of technically advanced scientific tools has boosted the basic discoveries in auxin biology. A plethora of bioactive small molecules, consisting of the synthetic auxin-like herbicides and the more specific auxin-related compounds, developed as a result of the exploration of chemical space by chemical biology, have made the tool box for auxin research more comprehensive. This review mainly focuses on the compounds targeting the auxin co-receptor complex, demonstrates the various ways to use them, and shows clear examples of important basic knowledge obtained by their usage. Application of these precise chemical tools, together with an increasing amount of structural information for the major components in auxin action, will certainly aid in strengthening our insights into the complexity and diversity of auxin response.
Collapse
Affiliation(s)
- Qian Ma
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Sweden
| | - Peter Grones
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Sweden
| | | |
Collapse
|
19
|
Hu Y, Depaepe T, Smet D, Hoyerova K, Klíma P, Cuypers A, Cutler S, Buyst D, Morreel K, Boerjan W, Martins J, Petrášek J, Vandenbussche F, Van Der Straeten D. ACCERBATIN, a small molecule at the intersection of auxin and reactive oxygen species homeostasis with herbicidal properties. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:4185-4203. [PMID: 28922768 PMCID: PMC5853866 DOI: 10.1093/jxb/erx242] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 06/22/2017] [Indexed: 05/30/2023]
Abstract
The volatile two-carbon hormone ethylene acts in concert with an array of signals to affect etiolated seedling development. From a chemical screen, we isolated a quinoline carboxamide designated ACCERBATIN (AEX) that exacerbates the 1-aminocyclopropane-1-carboxylic acid-induced triple response, typical for ethylene-treated seedlings in darkness. Phenotypic analyses revealed distinct AEX effects including inhibition of root hair development and shortening of the root meristem. Mutant analysis and reporter studies further suggested that AEX most probably acts in parallel to ethylene signaling. We demonstrated that AEX functions at the intersection of auxin metabolism and reactive oxygen species (ROS) homeostasis. AEX inhibited auxin efflux in BY-2 cells and promoted indole-3-acetic acid (IAA) oxidation in the shoot apical meristem and cotyledons of etiolated seedlings. Gene expression studies and superoxide/hydrogen peroxide staining further revealed that the disrupted auxin homeostasis was accompanied by oxidative stress. Interestingly, in light conditions, AEX exhibited properties reminiscent of the quinoline carboxylate-type auxin-like herbicides. We propose that AEX interferes with auxin transport from its major biosynthesis sites, either as a direct consequence of poor basipetal transport from the shoot meristematic region, or indirectly, through excessive IAA oxidation and ROS accumulation. Further investigation of AEX can provide new insights into the mechanisms connecting auxin and ROS homeostasis in plant development and provide useful tools to study auxin-type herbicides.
Collapse
Affiliation(s)
- Yuming Hu
- Laboratory of Functional Plant Biology, Department of Biology, Faculty of Sciences, Ghent University, K.L. Ledeganckstraat, Ghent, Belgium
| | - Thomas Depaepe
- Laboratory of Functional Plant Biology, Department of Biology, Faculty of Sciences, Ghent University, K.L. Ledeganckstraat, Ghent, Belgium
| | - Dajo Smet
- Laboratory of Functional Plant Biology, Department of Biology, Faculty of Sciences, Ghent University, K.L. Ledeganckstraat, Ghent, Belgium
| | - Klara Hoyerova
- Institute of Experimental Botany ASCR, Praha, Czech Republic
| | - Petr Klíma
- Institute of Experimental Botany ASCR, Praha, Czech Republic
| | - Ann Cuypers
- Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, Diepenbeek, Belgium
| | - Sean Cutler
- Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, CA, USA
| | - Dieter Buyst
- NMR and Structure Analysis, Department of Organic Chemistry, Krijgslaan, Ghent, Belgium
| | - Kris Morreel
- Department of Plant Systems Biology, VIB (Flanders Institute for Biotechnology), Technologiepark, Ghent, Belgium
| | - Wout Boerjan
- Department of Plant Systems Biology, VIB (Flanders Institute for Biotechnology), Technologiepark, Ghent, Belgium
| | - José Martins
- NMR and Structure Analysis, Department of Organic Chemistry, Krijgslaan, Ghent, Belgium
| | - Jan Petrášek
- Institute of Experimental Botany ASCR, Praha, Czech Republic
| | - Filip Vandenbussche
- Laboratory of Functional Plant Biology, Department of Biology, Faculty of Sciences, Ghent University, K.L. Ledeganckstraat, Ghent, Belgium
| | - Dominique Van Der Straeten
- Laboratory of Functional Plant Biology, Department of Biology, Faculty of Sciences, Ghent University, K.L. Ledeganckstraat, Ghent, Belgium
| |
Collapse
|
20
|
Abstract
Nearly all programmed and plastic plant growth responses are at least partially regulated by auxins, such as indole-3-acetic acid (IAA). Although vectorial, long distance auxin transport is essential to its regulatory function, all auxin responses are ultimately localized in individual target cells. As a consequence, cellular auxin concentrations are tightly regulated via coordinated biosynthesis, transport, conjugation, and oxidation. The primary auxin oxidative product across species is 2-oxindole-3-acetic acid (oxIAA), followed by glucose and amino acid conjugation to oxIAA. Recently, the enzymes catalyzing the oxidative reaction were characterized in Arabidopsis thaliana. DIOXYGENASE OF AUXIN OXIDATION (DAO) comprises a small subfamily of the 2-oxoglutarate and Fe(II) [2-OG Fe(II)] dependent dioxygenase superfamily. Biochemical and genetic studies have revealed critical physiological functions of DAO during plant growth and development. Thus far, DAO has been identified in three species by homology. Here, we review historical and recent studies and discuss future perspectives regarding DAO and IAA oxidation.
Collapse
Affiliation(s)
- Jun Zhang
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD 20742,USA
| | - Wendy Ann Peer
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD 20742, USA
- Department of Environmental Science and Technology, University of Maryland, College Park, MD 20742, USA
- Institute for Bioscience and Biotechnology Research, University of Maryland, College Park, MD 20742, USA
| |
Collapse
|
21
|
Hu Y, Vandenbussche F, Van Der Straeten D. Regulation of seedling growth by ethylene and the ethylene-auxin crosstalk. PLANTA 2017; 245:467-489. [PMID: 28188422 DOI: 10.1007/s00425-017-2651-6] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 01/08/2017] [Indexed: 05/06/2023]
Abstract
This review highlights that the auxin gradient, established by local auxin biosynthesis and transport, can be controlled by ethylene, and steers seedling growth. A better understanding of the mechanisms in Arabidopsis will increase potential applications in crop species. In dark-grown Arabidopsis seedlings, exogenous ethylene treatment triggers an exaggeration of the apical hook, the inhibition of both hypocotyl and root elongation, and radial swelling of the hypocotyl. These features are predominantly based on the differential cell elongation in different cells/tissues mediated by an auxin gradient. Interestingly, the physiological responses regulated by ethylene and auxin crosstalk can be either additive or synergistic, as in primary root and root hair elongation, or antagonistic, as in hypocotyl elongation. This review focuses on the crosstalk of these two hormones at the seedling stage. Before illustrating the crosstalk, ethylene and auxin biosynthesis, metabolism, transport and signaling are briefly discussed.
Collapse
Affiliation(s)
- Yuming Hu
- Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K.L. Ledeganckstraat 35, 9000, Ghent, Belgium
| | - Filip Vandenbussche
- Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K.L. Ledeganckstraat 35, 9000, Ghent, Belgium
| | - Dominique Van Der Straeten
- Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K.L. Ledeganckstraat 35, 9000, Ghent, Belgium.
| |
Collapse
|
22
|
Žižková E, Kubeš M, Dobrev PI, Přibyl P, Šimura J, Zahajská L, Záveská Drábková L, Novák O, Motyka V. Control of cytokinin and auxin homeostasis in cyanobacteria and algae. ANNALS OF BOTANY 2017; 119:151-166. [PMID: 27707748 PMCID: PMC5218379 DOI: 10.1093/aob/mcw194] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 07/18/2016] [Accepted: 08/11/2016] [Indexed: 05/10/2023]
Abstract
BACKGROUND AND AIMS The metabolism of cytokinins (CKs) and auxins in vascular plants is relatively well understood, but data concerning their metabolic pathways in non-vascular plants are still rather rare. With the aim of filling this gap, 20 representatives of taxonomically major lineages of cyanobacteria and algae from Cyanophyceae, Xanthophyceae, Eustigmatophyceae, Porphyridiophyceae, Chlorophyceae, Ulvophyceae, Trebouxiophyceae, Zygnematophyceae and Klebsormidiophyceae were analysed for endogenous profiles of CKs and auxins and some of them were used for studies of the metabolic fate of exogenously applied radiolabelled CK, [3H]trans-zeatin (transZ) and auxin ([3H]indole-3-acetic acid (IAA)), and the dynamics of endogenous CK and auxin pools during algal growth and cell division. METHODS Quantification of phytohormone levels was performed by high-performance or ultrahigh-performance liquid chromatography-electrospray tandem mass spectrometry (HPLC-MS/MS, UHPLC-MS/MS). The dynamics of exogenously applied [3H]transZ and [3H]IAA in cell cultures were monitored by HPLC with on-line radioactivity detection. KEY RESULTS The comprehensive screen of selected cyanobacteria and algae for endogenous CKs revealed a predominance of bioactive and phosphate CK forms while O- and N-glucosides evidently did not contribute greatly to the total CK pool. The abundance of cis-zeatin-type CKs and occurrence of CK 2-methylthio derivatives pointed to the tRNA pathway as a substantial source of CKs. The importance of the tRNA biosynthetic pathway was proved by the detection of tRNA-bound CKs during the course of Scenedesmus obliquus growth. Among auxins, free IAA and its oxidation catabolite 2-oxindole-3-acetic acid represented the prevailing endogenous forms. After treatment with [3H]IAA, IAA-aspartate and indole-3-acetyl-1-glucosyl ester were detected as major auxin metabolites. Moreover, different dynamics of endogenous CKs and auxin profiles during S. obliquus culture clearly demonstrated diverse roles of both phytohormones in algal growth and cell division. CONCLUSIONS Our data suggest the existence and functioning of a complex network of metabolic pathways and activity control of CKs and auxins in cyanobacteria and algae that apparently differ from those in vascular plants.
Collapse
Affiliation(s)
- Eva Žižková
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany CAS, Rozvojová 263, CZ-165 02 Prague 6, Czech Republic
| | - Martin Kubeš
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany CAS, Rozvojová 263, CZ-165 02 Prague 6, 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, CZ-783 71 Olomouc, Czech Republic
| | - Petre I Dobrev
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany CAS, Rozvojová 263, CZ-165 02 Prague 6, Czech Republic
| | - Pavel Přibyl
- Centre for Phycology and Biorefinery Research Centre of Competence, Institute of Botany CAS, Dukelská 135, CZ-379 82 Třeboň, Czech Republic
| | - Jan Šimura
- 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
| | - Lenka Zahajská
- Isotope Laboratory, Institute of Experimental Botany CAS, Vídeňská 1083, CZ-142 20 Prague 4, Czech Republic
| | - Lenka Záveská Drábková
- Department of Taxonomy and Biosystematics, Institute of Botany CAS, Zámek 1, CZ-252 43 Průhonice, Czech Republic
| | - Ondřej Novák
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science of Palacký University and Institute of Experimental Botany CAS, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic
| | - Václav Motyka
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany CAS, Rozvojová 263, CZ-165 02 Prague 6, Czech Republic
| |
Collapse
|
23
|
Kühn N, Serrano A, Abello C, Arce A, Espinoza C, Gouthu S, Deluc L, Arce-Johnson P. Regulation of polar auxin transport in grapevine fruitlets (Vitis vinifera L.) and the proposed role of auxin homeostasis during fruit abscission. BMC PLANT BIOLOGY 2016; 16:234. [PMID: 27793088 PMCID: PMC5084367 DOI: 10.1186/s12870-016-0914-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 10/04/2016] [Indexed: 05/05/2023]
Abstract
BACKGROUND Indole-3-acetic acid (IAA), the most abundant auxin, is a growth promoter hormone involved in several developmental processes. Auxin homeostasis is very important to its function and this is achieved through the regulation of IAA biosynthesis, conjugation, degradation and transport. In grapevine, IAA plays an essential role during initial stages of berry development, since it delays fruitlet abscission by reducing the ethylene sensitivity in the abscission zone. For this reason, Continuous polar IAA transport to the pedicel is required. This kind of transport is controlled by IAA, which regulates its own movement by modifying the expression and localization of PIN-FORMED (PIN) auxin efflux facilitators that localize asymmetrically within the cell. On the other hand, the hormone gibberellin (GA) also activates the polar auxin transport by increasing PIN stability. In Vitis vinifera, fruitlet abscission occurs during the first two to three weeks after flowering. During this time, IAA and GA are present, however the role of these hormones in the control of polar auxin transport is unknown. RESULTS In this work, the use of radiolabeled IAA showed that auxin is basipetally transported during grapevine fruitlet abscission. This observation was further supported by immunolocalization of putative VvPIN proteins that display a basipetal distribution in pericarp cells. Polar auxin transport and transcripts of four putative VvPIN genes decreased in conjunction with increased abscission, and the inhibition of polar auxin transport resulted in fruit drop. GA3 and IAA treatments reduced polar auxin transport, but only GA3 treatment decreased VvPIN transcript abundance. When GA biosynthesis was blocked, IAA was capable to increase polar auxin transport, suggesting that its effect depends on GA content. Finally, we observed significant changes in the content of several IAA-related compounds during the abscission period. CONCLUSIONS These results provide evidence that auxin homeostasis plays a central role during grapevine initial fruit development and that GA and IAA controls auxin homeostasis by reducing polar auxin transport.
Collapse
Affiliation(s)
- Nathalie Kühn
- Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Alameda 340, PO Box 114-D, Santiago, Chile
| | - Alejandra Serrano
- Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Alameda 340, PO Box 114-D, Santiago, Chile
| | - Carlos Abello
- Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Alameda 340, PO Box 114-D, Santiago, Chile
| | - Aníbal Arce
- Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Alameda 340, PO Box 114-D, Santiago, Chile
| | - Carmen Espinoza
- Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Alameda 340, PO Box 114-D, Santiago, Chile
| | | | - Laurent Deluc
- Department of Horticulture, Oregon State University, Corvallis, OR 97331 USA
| | - Patricio Arce-Johnson
- Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Alameda 340, PO Box 114-D, Santiago, Chile
| |
Collapse
|
24
|
Mellor N, Band LR, Pěnčík A, Novák O, Rashed A, Holman T, Wilson MH, Voß U, Bishopp A, King JR, Ljung K, Bennett MJ, Owen MR. Dynamic regulation of auxin oxidase and conjugating enzymes AtDAO1 and GH3 modulates auxin homeostasis. Proc Natl Acad Sci U S A 2016; 113:11022-7. [PMID: 27651495 PMCID: PMC5047161 DOI: 10.1073/pnas.1604458113] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The hormone auxin is a key regulator of plant growth and development, and great progress has been made understanding auxin transport and signaling. Here, we show that auxin metabolism and homeostasis are also regulated in a complex manner. The principal auxin degradation pathways in Arabidopsis include oxidation by Arabidopsis thaliana gene DIOXYGENASE FOR AUXIN OXIDATION 1/2 (AtDAO1/2) and conjugation by Gretchen Hagen3s (GH3s). Metabolic profiling of dao1-1 root tissues revealed a 50% decrease in the oxidation product 2-oxoindole-3-acetic acid (oxIAA) and increases in the conjugated forms indole-3-acetic acid aspartic acid (IAA-Asp) and indole-3-acetic acid glutamic acid (IAA-Glu) of 438- and 240-fold, respectively, whereas auxin remains close to the WT. By fitting parameter values to a mathematical model of these metabolic pathways, we show that, in addition to reduced oxidation, both auxin biosynthesis and conjugation are increased in dao1-1 Transcripts of AtDAO1 and GH3 genes increase in response to auxin over different timescales and concentration ranges. Including this regulation of AtDAO1 and GH3 in an extended model reveals that auxin oxidation is more important for auxin homoeostasis at lower hormone concentrations, whereas auxin conjugation is most significant at high auxin levels. Finally, embedding our homeostasis model in a multicellular simulation to assess the spatial effect of the dao1-1 mutant shows that auxin increases in outer root tissues in agreement with the dao1-1 mutant root hair phenotype. We conclude that auxin homeostasis is dependent on AtDAO1, acting in concert with GH3, to maintain auxin at optimal levels for plant growth and development.
Collapse
Affiliation(s)
- Nathan Mellor
- Centre for Plant Integrative Biology, Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, United Kingdom; Centre for Mathematical Medicine and Biology, School of Mathematical Sciences, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Leah R Band
- Centre for Plant Integrative Biology, Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, United Kingdom; Centre for Mathematical Medicine and Biology, School of Mathematical Sciences, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Aleš Pěnčík
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83 Umea, Sweden
| | - Ondřej Novák
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83 Umea, Sweden
| | - Afaf Rashed
- Centre for Plant Integrative Biology, Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, United Kingdom
| | - Tara Holman
- Centre for Plant Integrative Biology, Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, United Kingdom
| | - Michael H Wilson
- Centre for Plant Integrative Biology, Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, United Kingdom; Centre for Plant Sciences, School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Ute Voß
- Centre for Plant Integrative Biology, Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, United Kingdom
| | - Anthony Bishopp
- Centre for Plant Integrative Biology, Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, United Kingdom
| | - John R King
- Centre for Plant Integrative Biology, Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, United Kingdom; Centre for Mathematical Medicine and Biology, School of Mathematical Sciences, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Karin Ljung
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83 Umea, Sweden
| | - Malcolm J Bennett
- Centre for Plant Integrative Biology, Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, United Kingdom; Centre for Mathematical Medicine and Biology, School of Mathematical Sciences, University of Nottingham, Nottingham NG7 2RD, United Kingdom;
| | - Markus R Owen
- Centre for Plant Integrative Biology, Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, United Kingdom; Centre for Mathematical Medicine and Biology, School of Mathematical Sciences, University of Nottingham, Nottingham NG7 2RD, United Kingdom;
| |
Collapse
|
25
|
Dioxygenase-encoding AtDAO1 gene controls IAA oxidation and homeostasis in Arabidopsis. Proc Natl Acad Sci U S A 2016; 113:11016-21. [PMID: 27651491 DOI: 10.1073/pnas.1604375113] [Citation(s) in RCA: 124] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Auxin represents a key signal in plants, regulating almost every aspect of their growth and development. Major breakthroughs have been made dissecting the molecular basis of auxin transport, perception, and response. In contrast, how plants control the metabolism and homeostasis of the major form of auxin in plants, indole-3-acetic acid (IAA), remains unclear. In this paper, we initially describe the function of the Arabidopsis thaliana gene DIOXYGENASE FOR AUXIN OXIDATION 1 (AtDAO1). Transcriptional and translational reporter lines revealed that AtDAO1 encodes a highly root-expressed, cytoplasmically localized IAA oxidase. Stable isotope-labeled IAA feeding studies of loss and gain of function AtDAO1 lines showed that this oxidase represents the major regulator of auxin degradation to 2-oxoindole-3-acetic acid (oxIAA) in Arabidopsis Surprisingly, AtDAO1 loss and gain of function lines exhibited relatively subtle auxin-related phenotypes, such as altered root hair length. Metabolite profiling of mutant lines revealed that disrupting AtDAO1 regulation resulted in major changes in steady-state levels of oxIAA and IAA conjugates but not IAA. Hence, IAA conjugation and catabolism seem to regulate auxin levels in Arabidopsis in a highly redundant manner. We observed that transcripts of AtDOA1 IAA oxidase and GH3 IAA-conjugating enzymes are auxin-inducible, providing a molecular basis for their observed functional redundancy. We conclude that the AtDAO1 gene plays a key role regulating auxin homeostasis in Arabidopsis, acting in concert with GH3 genes, to maintain auxin concentration at optimal levels for plant growth and development.
Collapse
|
26
|
Yue X, Li XG, Gao XQ, Zhao XY, Dong YX, Zhou C. The Arabidopsis phytohormone crosstalk network involves a consecutive metabolic route and circular control units of transcription factors that regulate enzyme-encoding genes. BMC SYSTEMS BIOLOGY 2016; 10:87. [PMID: 27590055 PMCID: PMC5009710 DOI: 10.1186/s12918-016-0333-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 08/25/2016] [Indexed: 01/26/2023]
Abstract
Background Phytohormone synergies and signaling interdependency are important topics in plant developmental biology. Physiological and genetic experimental evidence for phytohormone crosstalk has been accumulating and a genome-scale enzyme correlation model representing the Arabidopsis metabolic pathway has been published. However, an integrated molecular characterization of phytohormone crosstalk is still not available. Results A novel modeling methodology and advanced computational approaches were used to construct an enzyme-based Arabidopsis phytohormone crosstalk network (EAPCN) at the biosynthesis level. The EAPCN provided the structural connectivity architecture of phytohormone biosynthesis pathways and revealed a surprising result; that enzymes localized at the highly connected nodes formed a consecutive metabolic route. Furthermore, our analysis revealed that the transcription factors (TFs) that regulate enzyme-encoding genes in the consecutive metabolic route formed structures, which we describe as circular control units operating at the transcriptional level. Furthermore, the downstream TFs in phytohormone signal transduction pathways were found to be involved in the circular control units that included the TFs regulating enzyme-encoding genes. In addition, multiple functional enzymes in the EAPCN were found to be involved in ion and pH homeostasis, environmental signal perception, cellular redox homeostasis, and circadian clocks. Last, publicly available transcriptional profiles and a protein expression map of the Arabidopsis root apical meristem were used as a case study to validate the proposed framework. Conclusions Our results revealed multiple scales of coupled mechanisms in that hormonal crosstalk networks that play a central role in coordinating internal developmental processes with environmental signals, and give a broader view of Arabidopsis phytohormone crosstalk. We also uncovered potential key regulators that can be further analyzed in future studies. Electronic supplementary material The online version of this article (doi:10.1186/s12918-016-0333-9) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Xun Yue
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China. .,State Key Laboratory of Crop Biology, College of Information Sciences and Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China.
| | - Xing Guo Li
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Xin-Qi Gao
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Xiang Yu Zhao
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Yu Xiu Dong
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Chao Zhou
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| |
Collapse
|
27
|
Sanchez Carranza AP, Singh A, Steinberger K, Panigrahi K, Palme K, Dovzhenko A, Dal Bosco C. Hydrolases of the ILR1-like family of Arabidopsis thaliana modulate auxin response by regulating auxin homeostasis in the endoplasmic reticulum. Sci Rep 2016; 6:24212. [PMID: 27063913 PMCID: PMC4827090 DOI: 10.1038/srep24212] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 03/22/2016] [Indexed: 12/21/2022] Open
Abstract
Amide-linked conjugates of indole-3-acetic acid (IAA) have been identified in most plant species. They function in storage, inactivation or inhibition of the growth regulator auxin. We investigated how the major known endogenous amide-linked IAA conjugates with auxin-like activity act in auxin signaling and what role ILR1-like proteins play in this process in Arabidopsis. We used a genetically encoded auxin sensor to show that IAA-Leu, IAA-Ala and IAA-Phe act through the TIR1-dependent signaling pathway. Furthermore, by using the sensor as a free IAA reporter, we followed conjugate hydrolysis mediated by ILR1, ILL2 and IAR3 in plant cells and correlated the activity of the hydrolases with a modulation of auxin response. The conjugate preferences that we observed are in agreement with available in vitro data for ILR1. Moreover, we identified IAA-Leu as an additional substrate for IAR3 and showed that ILL2 has a more moderate kinetic performance than observed in vitro. Finally, we proved that IAR3, ILL2 and ILR1 reside in the endoplasmic reticulum, indicating that in this compartment the hydrolases regulate the rates of amido-IAA hydrolysis which results in activation of auxin signaling.
Collapse
Affiliation(s)
- Ana Paula Sanchez Carranza
- Institute of Biology II/Molecular Plant Physiology, Faculty of Biology, Albert-Ludwigs-University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany
| | - Aparajita Singh
- Institute of Biology II/Molecular Plant Physiology, Faculty of Biology, Albert-Ludwigs-University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany
| | - Karoline Steinberger
- Institute of Biology II/Molecular Plant Physiology, Faculty of Biology, Albert-Ludwigs-University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany
| | - Kishore Panigrahi
- National Institute of Science Education and Research, Institute of Physics Campus, Bhubaneswar, Odisha 751005, India
| | - Klaus Palme
- Institute of Biology II/Molecular Plant Physiology, Faculty of Biology, Albert-Ludwigs-University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany.,BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany.,Freiburg Institute for Advanced Sciences (FRIAS), University of Freiburg, 79104 Freiburg, Germany.,Centre for Biological Systems Analysis (ZBSA), University of Freiburg, 79104 Freiburg, Germany
| | - Alexander Dovzhenko
- Institute of Biology II/Molecular Plant Physiology, Faculty of Biology, Albert-Ludwigs-University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany
| | - Cristina Dal Bosco
- Institute of Biology II/Molecular Plant Physiology, Faculty of Biology, Albert-Ludwigs-University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany
| |
Collapse
|
28
|
Ostrowski M, Ciarkowska A, Jakubowska A. The auxin conjugate indole-3-acetyl-aspartate affects responses to cadmium and salt stress in Pisum sativum L. JOURNAL OF PLANT PHYSIOLOGY 2016; 191:63-72. [PMID: 26717013 DOI: 10.1016/j.jplph.2015.11.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 11/25/2015] [Accepted: 11/25/2015] [Indexed: 05/20/2023]
Abstract
The synthesis of IAA-amino acid conjugates is one of the crucial regulatory mechanisms for the control of auxin activity during physiological and pathophysiological responses. Indole-3-acetyl-aspartate (IAA-Asp) is a low molecular weight amide conjugate that predominates in pea (Pisum sativum L.) tissues. IAA-Asp acts as an intermediate during the auxin degradation pathway. However, some recent investigations suggest a direct signaling function of this conjugate in various processes. In this study, we examine the effect of 100 μM IAA-Asp alone and in combination with salt stress (160 mM NaCl) or heavy metal stress (250 μM CdCl2) on H2O2 concentration, protein carbonylation as well as catalase and ascorbate (APX) and guaiacol peroxidase (GPX) activities in 7-day-old pea seedlings. As revealed by spectrophotometric analyses, IAA-Asp increased the carbonylated protein level and reduced the H2O2 concentration. Moreover, IAA-aspartate potentiated the effect of both Cd(2+) ions and NaCl on the H2O2 level. The enzymatic activities (catalase and peroxidases) were examined using spectrophotometric and native-PAGE assays. IAA-Asp alone did not affect catalase activity, whereas the two peroxidases were regulated differently. IAA-Asp reduced the APX activity during 48h cultivation. APX activity was potentiated by IAA-Asp+NaCl after 48h. Guaiacol peroxidase activity was diminished by all tested compounds. Based on these results, we suggest that IAA-Asp can directly and specifically affect the pea responses to abiotic stress.
Collapse
Affiliation(s)
- Maciej Ostrowski
- Nicolaus Copernicus University, Department of Biochemistry, Lwowska 1 87-100 Torun, Poland.
| | - Anna Ciarkowska
- Nicolaus Copernicus University, Department of Biochemistry, Lwowska 1 87-100 Torun, Poland
| | - Anna Jakubowska
- Nicolaus Copernicus University, Department of Biochemistry, Lwowska 1 87-100 Torun, Poland
| |
Collapse
|
29
|
Kuhn BM, Errafi S, Bucher R, Dobrev P, Geisler M, Bigler L, Zažímalová E, Ringli C. 7-Rhamnosylated Flavonols Modulate Homeostasis of the Plant Hormone Auxin and Affect Plant Development. J Biol Chem 2016; 291:5385-95. [PMID: 26742840 DOI: 10.1074/jbc.m115.701565] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Indexed: 11/06/2022] Open
Abstract
Flavonols are a group of secondary metabolites that affect diverse cellular processes. They are considered putative negative regulators of the transport of the phytohormone auxin, by which they influence auxin distribution and concomitantly take part in the control of plant organ development. Flavonols are accumulating in a large number of glycosidic forms. Whether these have distinct functions and diverse cellular targets is not well understood. The rol1-2 mutant of Arabidopsis thaliana is characterized by a modified flavonol glycosylation profile that is inducing changes in auxin transport and growth defects in shoot tissues. To determine whether specific flavonol glycosides are responsible for these phenotypes, a suppressor screen was performed on the rol1-2 mutant, resulting in the identification of an allelic series of UGT89C1, a gene encoding a flavonol 7-O-rhamnosyltransferase. A detailed analysis revealed that interfering with flavonol rhamnosylation increases the concentration of auxin precursors and auxin metabolites, whereas auxin transport is not affected. This finding provides an additional level of complexity to the possible ways by which flavonols influence auxin distribution and suggests that flavonol glycosides play an important role in regulating plant development.
Collapse
Affiliation(s)
- Benjamin M Kuhn
- From the Department of Plant and Microbial Biology, University of Zurich, 8008 Zurich, Switzerland
| | - Sanae Errafi
- From the Department of Plant and Microbial Biology, University of Zurich, 8008 Zurich, Switzerland
| | - Rahel Bucher
- the Department of Chemistry, University of Zurich, 8057 Zurich, Switzerland
| | - Petre Dobrev
- the Institute of Experimental Botany, Academy of Sciences of the Czech Republic, 165 02 Prague 6, Czech Republic, and
| | - Markus Geisler
- the Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Laurent Bigler
- the Department of Chemistry, University of Zurich, 8057 Zurich, Switzerland
| | - Eva Zažímalová
- the Institute of Experimental Botany, Academy of Sciences of the Czech Republic, 165 02 Prague 6, Czech Republic, and
| | - Christoph Ringli
- From the Department of Plant and Microbial Biology, University of Zurich, 8008 Zurich, Switzerland,
| |
Collapse
|
30
|
Feng S, Li C. Stereospecific, High-Yielding, and Green Synthesis of β-Glycosyl Esters. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:5732-9. [PMID: 26042825 DOI: 10.1021/acs.jafc.5b02534] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
A new method of synthesizing β-glycosyl esters stereospecifically has been developed by treating O-benzyl-protected glycosyl chlorides with Cs2CO3, tetrabutylammomium bromide (TBAB), a carboxylic acid, water, and granular polytetrafluoroethylene (PTFE) at 80 °C under mechanical agitation. D-Glucosyl, D-xylosyl, and D-galactosyl chlorides and 20 carboxylic acids were used to demonstrate the scope of the reaction. Control experiments showed that the water and granular PTFE had indispensable roles. Water-soluble TBAB has been found to be as efficient as N-methyl-N,N,N-trioctyloctan-1-ammonium chloride (Aliquat 336) in the reactions. After scaling up to 5-12 g, all of the products were obtained quantitatively via simple filtration and no organic solvents or chromatography was needed for the entire process.
Collapse
Affiliation(s)
- Suliu Feng
- Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China
| | - Chunbao Li
- Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China
| |
Collapse
|
31
|
Bochicchio R, Sofo A, Terzano R, Gattullo CE, Amato M, Scopa A. Root architecture and morphometric analysis of Arabidopsis thaliana grown in Cd/Cu/Zn-gradient agar dishes: A new screening technique for studying plant response to metals. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2015; 91:20-7. [PMID: 25839424 DOI: 10.1016/j.plaphy.2015.03.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 03/27/2015] [Indexed: 05/24/2023]
Abstract
A new screening strategy using Petri dishes with a gradient of distances between germinating seeds and a metal-contaminated medium was used for studying alterations in root architecture and morphology of Arabidopsis thaliana treated with cadmium, copper and zinc at sub-toxic concentrations. Metal concentrations in the dishes were determined by anodic stripping voltammetry on digested agar samples collected along the gradient, and kriging statistical interpolation method was performed. After two weeks, all agar dishes were scanned at high resolution and the root systems analyzed. In the presence of all the three metals, primary root length did not significantly change compared to controls, excepting for zinc applied alone (+45% of controls). In metal-treated seedlings, root system total length increased due to the higher number of lateral roots. The seedlings closer to the agar sectors including metals showed a marked curvature and a higher root branching in comparison to those further away from the metals. This behavior, together with an observed increase in root diameter in metal-treated seedlings could be interpreted as compensatory growth, and a thicker roots could act as a barrier to protect root from the metals. We therefore propose that the remodeling of the root architecture in response to metals could be a pollution 'escaping strategy' aimed at seeking metal-free patches.
Collapse
Affiliation(s)
- Rocco Bochicchio
- School of Agricultural, Forestry, Food and Environmental Sciences (SAFE), Università degli Studi della Basilicata, Viale dell' Ateneo Lucano, 10, 85100 Potenza, Italy.
| | - Adriano Sofo
- School of Agricultural, Forestry, Food and Environmental Sciences (SAFE), Università degli Studi della Basilicata, Viale dell' Ateneo Lucano, 10, 85100 Potenza, Italy.
| | - Roberto Terzano
- Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti (DiSSPA), Università degli Studi di Bari, Via Orabona, 4, 70126 Bari, Italy.
| | - Concetta Eliana Gattullo
- Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti (DiSSPA), Università degli Studi di Bari, Via Orabona, 4, 70126 Bari, Italy.
| | - Mariana Amato
- School of Agricultural, Forestry, Food and Environmental Sciences (SAFE), Università degli Studi della Basilicata, Viale dell' Ateneo Lucano, 10, 85100 Potenza, Italy.
| | - Antonio Scopa
- School of Agricultural, Forestry, Food and Environmental Sciences (SAFE), Università degli Studi della Basilicata, Viale dell' Ateneo Lucano, 10, 85100 Potenza, Italy.
| |
Collapse
|
32
|
Yu P, Lor P, Ludwig-Müller J, Hegeman AD, Cohen JD. Quantitative evaluation of IAA conjugate pools in Arabidopsis thaliana. PLANTA 2015; 241:539-548. [PMID: 25420555 DOI: 10.1007/s00425-014-2206-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 11/10/2014] [Indexed: 06/04/2023]
Abstract
This work has demonstrated that the major method of estimating the amount of unknown IAA conjugates-base hydrolysis-can be significantly complicated by chemical artifacts such as glucobrassicin or protein degradation. The concept of 'bound auxin' traces its origin back to more than 80 years ago and has driven research on the sources and forms of these plant hormones since. Indeed, analytical studies have demonstrated that the majority of cellular auxin is conjugated to simple sugars, cyclitols, glycans, amino acids, and other biomolecules. A number of studies have confirmed the enzymatic systems responsible for the synthesis and hydrolysis of a number of such conjugates in Arabidopsis thaliana and some of these compounds have been identified in situ. However, the amount of indole-3-acetic acid (IAA) released upon treating Arabidopsis tissue extracts with base, a commonly employed technique for estimating the amount of IAA conjugates, greatly exceeded the summation of all the IAA conjugates known individually to be present in Arabidopsis. This discrepancy has remained as an unsolved question. In this study, however, we found that a significant portion of the IAA found after base treatment could be attributed to chemical conversions other than conjugate hydrolysis. Specifically, we showed that glucobrassicin conversion, previously thought to occur at insignificant levels, actually accounted for the majority of solvent soluble IAA released and that proteinaceous tryptophan degradation accounted for a large portion of solvent insoluble IAA. These studies clearly demonstrated the limits associated with using a harsh technique like base hydrolysis in determining IAA conjugates and support using more direct approaches such as mass spectrometry-based strategies for unambiguous characterizations of the total complement of IAA conjugates in new plant materials under study.
Collapse
Affiliation(s)
- Peng Yu
- Department of Horticultural Science, Microbial and Plant Genomics Institute, University of Minnesota, 1970 Folwell Avenue, Saint Paul, MN, 55108, USA,
| | | | | | | | | |
Collapse
|
33
|
Guyon C, Métay E, Popowycz F, Lemaire M. Synthetic applications of hypophosphite derivatives in reduction. Org Biomol Chem 2015; 13:7879-906. [DOI: 10.1039/c5ob01032b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The purpose of this review is to collect the applications in fine synthesis of hypophosphite derivatives as reducing agents.
Collapse
Affiliation(s)
- Carole Guyon
- Equipe Catalyse Synthèse Environnement
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires
- UMR-CNRS 5246
- Université de Lyon
- Université Claude Bernard-Lyon 1
| | - Estelle Métay
- Equipe Catalyse Synthèse Environnement
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires
- UMR-CNRS 5246
- Université de Lyon
- Université Claude Bernard-Lyon 1
| | - Florence Popowycz
- Equipe Chimie Organique et Bioorganique
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires
- UMR-CNRS 5246
- Institut National des Sciences Appliquées (INSA Lyon)
- F-69621 Villeurbanne Cedex
| | - Marc Lemaire
- Equipe Catalyse Synthèse Environnement
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires
- UMR-CNRS 5246
- Université de Lyon
- Université Claude Bernard-Lyon 1
| |
Collapse
|
34
|
Tarkowská D, Novák O, Floková K, Tarkowski P, Turečková V, Grúz J, Rolčík J, Strnad M. Quo vadis plant hormone analysis? PLANTA 2014; 240:55-76. [PMID: 24677098 DOI: 10.1007/s00425-014-2063-9] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 03/08/2014] [Indexed: 05/04/2023]
Abstract
Plant hormones act as chemical messengers in the regulation of myriads of physiological processes that occur in plants. To date, nine groups of plant hormones have been identified and more will probably be discovered. Furthermore, members of each group may participate in the regulation of physiological responses in planta both alone and in concert with members of either the same group or other groups. The ideal way to study biochemical processes involving these signalling molecules is 'hormone profiling', i.e. quantification of not only the hormones themselves, but also their biosynthetic precursors and metabolites in plant tissues. However, this is highly challenging since trace amounts of all of these substances are present in highly complex plant matrices. Here, we review advances, current trends and future perspectives in the analysis of all currently known plant hormones and the associated problems of extracting them from plant tissues and separating them from the numerous potentially interfering compounds.
Collapse
Affiliation(s)
- Danuše Tarkowská
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany ASCR and Palacký University, Šlechtitelů 11, 783 71, Olomouc, Czech Republic,
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Xu XT, Liu C, Zhang XR, Xing YH, Zhang HZ, Bai FY. Synthesis, structure, fluorescence spectra study of two kinds of coordination supramolecular zinc compounds. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 127:131-136. [PMID: 24632166 DOI: 10.1016/j.saa.2014.02.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 01/26/2014] [Accepted: 02/09/2014] [Indexed: 06/03/2023]
Abstract
Two novel compounds [Zn(IAA)2(phen) (HIAA=indole-3-acetic acid, phen=1,10-phenanthroline) (1) and [Zn(IAA)2(4,4'-bipy)](4,4'-bipy=4,4'-bipyridine) (2) were synthesized by the reaction of Zn(Ac)2·2H2O or Zn(SO4)·4H2O as a metal source, HIAA as the first ligand and phen or 4,4'-bipy as the second ligand in the system of methanol or the mixed solution of methanol and water at room temperature. They were characterized by elemental analysis, IR spectroscopy, UV-vis spectra and single-crystal X-ray diffraction. Structural analysis shows that the center metal Zn(II) for the compound 1 is four-coordinated, displaying a distorted tetrahedron; the metal center coordinated model for compound 2 is similar to that of 1, in which the structural unit of Zn(IAA)2 was connected by bridging the 4, 4'- bipy ligand to form an infinite 1D chain. In the packing of the compounds, there are some hydrogen bonding interactions and by the hydrogen bonding, 1D and 2D supramolecular structures were formed. Additional, we have studied the fluorescent properties of the two compounds.
Collapse
Affiliation(s)
- Xue-Ting Xu
- College of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, PR China
| | - Cong Liu
- College of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, PR China
| | - Xin-Rui Zhang
- College of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, PR China
| | - Yong-Heng Xing
- College of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, PR China.
| | - Huan-Zhi Zhang
- Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004, PR China
| | - Feng-Ying Bai
- College of Life Sciences, Liaoning Normal University, Dalian 116029, PR China.
| |
Collapse
|
36
|
Vitti A, Nuzzaci M, Scopa A, Tataranni G, Tamburrino I, Sofo A. Hormonal response and root architecture in Arabidopsis thaliana subjected to heavy metals. INTERNATIONAL JOURNAL OF PLANT BIOLOGY 2014. [DOI: 10.4081/pb.2014.5226] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
In this work, specific concentrations of cadmium, copper and zinc in double combination, were supplied for 12 days to growing seedlings of the model species <em>Arabidopsis</em> <em>thaliana</em>. Metal accumulation was measured in roots and shoots. Microscopic analyses revealed that root morphology was affected by metals, and that the root and shoot levels of indole-3-acetic acid, <em>trans</em>-zeatin riboside and dihydrozeatin riboside varied accordingly. Minor modifications in gibberellic acid levels occurred in the Zinc treatments, whereas abscisic acid level did not change after the exposition to metals. Reverse transcription polymerase chain reaction analysis of some genes involved in auxin and cytokinin synthesis (<em>AtAAO</em>, <em>AtNIT</em> and <em>AtIPT</em>) revealed that their expression were not affected by metal treatments. The root morphological alterations that resulted in an increased surface area, due to the formation of root hairs and lateral roots, could be signs of the response to metal stress in terms of a functionally-addressed reorientation of root growth. The root system plasticity observed could be important for better understanding the manner in which the root architecture is shaped by environmental and hormonal stimuli.
Collapse
|
37
|
Kai K, Nakamura S, Wakasa K, Miyagawa H. Facile Preparation of Deuterium-Labeled Standards of Indole-3-Acetic Acid (IAA) and Its Metabolites to Quantitatively Analyze the Disposition of Exogenous IAA inArabidopsis thaliana. Biosci Biotechnol Biochem 2014; 71:1946-54. [PMID: 17690468 DOI: 10.1271/bbb.70151] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
[2',2'-(2)H(2)]-indole-3-acetic acid ([2',2'-(2)H(2)]IAA) was prepared in an easy and efficient manner involving base-catalyzed hydrogen/deuterium exchange. 1-O-([2',2'-(2)H(2)]-indole-3-acetyl)-beta-D-glucopyranose, [2',2'-(2)H(2)]-2-oxoindole-3-acetic acid, and 1-O-([2',2'-(2)H(2)]-2-oxoindole-3-acetyl)-beta-D-glucopyranose were also successfully synthesized from deuterated IAA, and effectively utilized as internal standards in the quantitative analysis of IAA and its metabolites in Arabidopsis thaliana by using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). The use of this technique shows that these metabolites were accumulated in the roots of Arabidopsis seedlings. Dynamic changes in the metabolites of IAA were observed in response to exogenous IAA, revealing that each metabolic action was regulated differently to contribute to the IAA homeostasis in Arabidopsis.
Collapse
Affiliation(s)
- Kenji Kai
- Division of Applied Life Science, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | | | | | | |
Collapse
|
38
|
Zhang S, Wu J, Yuan D, Zhang D, Huang Z, Xiao L, Yang C. Perturbation of auxin homeostasis caused by mitochondrial FtSH4 gene-mediated peroxidase accumulation regulates arabidopsis architecture. MOLECULAR PLANT 2014; 7:856-73. [PMID: 24482432 DOI: 10.1093/mp/ssu006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Reactive oxygen species and auxin play important roles in the networks that regulate plant development and morphogenetic changes. However, the molecular mechanisms underlying the interactions between them are poorly understood. This study isolated a mas (More Axillary Shoots) mutant, which was identified as an allele of the mitochondrial AAA-protease AtFtSH4, and characterized the function of the FtSH4 gene in regulating plant development by mediating the peroxidase-dependent interplay between hydrogen peroxide (H2O2) and auxin homeostasis. The phenotypes of dwarfism and increased axillary branches observed in the mas (renamed as ftsh4-4) mutant result from a decrease in the IAA concentration. The expression levels of several auxin signaling genes, including IAA1, IAA2, and IAA3, as well as several auxin binding and transport genes, decreased significantly in ftsh4-4 plants. However, the H2O2 and peroxidases levels, which also have IAA oxidase activity, were significantly elevated in ftsh4-4 plants. The ftsh4-4 phenotypes could be reversed by expressing the iaaM gene or by knocking down the peroxidase genes PRX34 and PRX33. Both approaches can increase auxin levels in the ftsh4-4 mutant. Taken together, these results provided direct molecular and genetic evidence for the interaction between mitochondrial ATP-dependent protease, H2O2, and auxin homeostasis to regulate plant growth and development.
Collapse
Affiliation(s)
- Shengchun Zhang
- Guangdong Key Lab of Biotechnology for Plant Development, College of Life Sciences, South China Normal University, Guangzhou 510631, China
| | | | | | | | | | | | | |
Collapse
|
39
|
Yang L, Wang G, Wang M, Jiang H, Chen L, Zhao F, Qiu F. Indole alkaloids from the roots of Isatis indigotica and their inhibitory effects on nitric oxide production. Fitoterapia 2014; 95:175-81. [PMID: 24685504 DOI: 10.1016/j.fitote.2014.03.019] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 03/14/2014] [Accepted: 03/22/2014] [Indexed: 11/30/2022]
Abstract
Three rare indole-2-S-glycosides, indole-3-acetonitrile-2-S-β-D-glucopyranoside (1), indole-3-acetonitrile-4-methoxy-2-S-β-D-glucopyranoside (2) and N-methoxy-indole-3-acetonitrile-2-S-β-D-glucopyranoside (3), together with 11 known indole alkaloids were isolated from the roots of Isatis indigotica Fort. (Cruciferae). The structures of 1-3 were elucidated on the basis of mass spectrometry and extensive 1D and 2D NMR spectroscopy. All of the isolated compounds were tested for inhibitory activity against LPS-induced nitric oxide production in RAW 264.7 macrophages. A plausible biosynthesis pathway of 1-3 is also proposed.
Collapse
Affiliation(s)
- Liguo Yang
- Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang 110016, PR China; Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, PR China
| | - Guan Wang
- Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang 110016, PR China; Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, PR China
| | - Meng Wang
- Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang 110016, PR China; Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, PR China
| | - Hongmei Jiang
- Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang 110016, PR China; Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, PR China
| | - Lixia Chen
- Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang 110016, PR China; Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, PR China
| | - Feng Zhao
- School of Pharmacy, Yantai University, Yantai 264005, PR China.
| | - Feng Qiu
- Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang 110016, PR China; Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, PR China; Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 300193, PR China.
| |
Collapse
|
40
|
Guyon C, Baron M, Lemaire M, Popowycz F, Métay E. Commutative reduction of aromatic ketones to arylmethylenes/alcohols by hypophosphites catalyzed by Pd/C under biphasic conditions. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.02.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
41
|
Tanaka K, Hayashi KI, Natsume M, Kamiya Y, Sakakibara H, Kawaide H, Kasahara H. UGT74D1 catalyzes the glucosylation of 2-oxindole-3-acetic acid in the auxin metabolic pathway in Arabidopsis. PLANT & CELL PHYSIOLOGY 2014; 55:218-28. [PMID: 24285754 PMCID: PMC3894777 DOI: 10.1093/pcp/pct173] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 11/19/2013] [Indexed: 05/18/2023]
Abstract
IAA is a naturally occurring auxin that plays a crucial role in the regulation of plant growth and development. The endogenous concentration of IAA is spatiotemporally regulated by biosynthesis, transport and its inactivation in plants. Previous studies have shown that the metabolism of IAA to 2-oxindole-3-acetic acid (OxIAA) and OxIAA-glucoside (OxIAA-Glc) may play an important role in IAA homeostasis, but the genes involved in this metabolic pathway are still unknown. In this study, we show that UGT74D1 catalyzes the glucosylation of OxIAA in Arabidopsis. By screening yeasts transformed with Arabidopsis UDP-glycosyltransferase (UGT) genes, we found that OxIAA-Glc accumulates in the culture media of yeasts expressing UGT74D1 in the presence of OxIAA. Further, we showed that UGT74D1 expressed in Escherichia coli converts OxIAA to OxIAA-Glc. The endogenous concentration of OxIAA-Glc decreased by 85% while that of OxIAA increased 2.5-fold in ugt74d1-deficient mutants, indicating the major role of UGT74D1 in OxIAA metabolism. Moreover, the induction of UGT74D1 markedly increased the level of OxIAA-Glc and loss of root gravitropism. These results indicate that UGT74D1 catalyzes a committed step in the OxIAA-dependent IAA metabolic pathway in Arabidopsis.
Collapse
Affiliation(s)
- Keita Tanaka
- United Graduate School of Agricultural Science, Tokyo
University of Agriculture & Technology, Tokyo, 183-8509 Japan
- RIKEN Center for Sustainable Resource Science, Yokohama,
Kanagawa, 230-0045 Japan
| | - Ken-ichiro Hayashi
- Department of Biochemistry, Okayama University of Science,
Okayama, 700-0005 Japan
| | - Masahiro Natsume
- United Graduate School of Agricultural Science, Tokyo
University of Agriculture & Technology, Tokyo, 183-8509 Japan
| | - Yuji Kamiya
- RIKEN Center for Sustainable Resource Science, Yokohama,
Kanagawa, 230-0045 Japan
| | - Hitoshi Sakakibara
- RIKEN Center for Sustainable Resource Science, Yokohama,
Kanagawa, 230-0045 Japan
| | - Hiroshi Kawaide
- United Graduate School of Agricultural Science, Tokyo
University of Agriculture & Technology, Tokyo, 183-8509 Japan
| | - Hiroyuki Kasahara
- RIKEN Center for Sustainable Resource Science, Yokohama,
Kanagawa, 230-0045 Japan
- Japan Science and Technology Agency (JST), Precursory
Research for Embryonic Science and Technology (PRESTO), Saitama, 332-0012 Japan
- *Corresponding author: E-mail,
; Fax +81-45-503-9665
| |
Collapse
|
42
|
Sofo A, Vitti A, Nuzzaci M, Tataranni G, Scopa A, Vangronsveld J, Remans T, Falasca G, Altamura MM, Degola F, Sanità di Toppi L. Correlation between hormonal homeostasis and morphogenic responses in Arabidopsis thaliana seedlings growing in a Cd/Cu/Zn multi-pollution context. PHYSIOLOGIA PLANTARUM 2013; 149:487-98. [PMID: 23496095 DOI: 10.1111/ppl.12050] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 03/08/2013] [Accepted: 03/10/2013] [Indexed: 05/04/2023]
Abstract
To date, almost no information is available in roots and shoots of the model plant Arabidopsis thaliana about the hierarchic relationship between metal accumulation, phytohormone levels, and glutathione/phytochelatin content, and how this relation affects root development. For this purpose, specific concentrations of cadmium, copper and zinc, alone or in triple combination, were supplied for 12 days to in vitro growing seedlings. The accumulation of these metals was measured in roots and shoots, and a significant competition in metal uptake was observed. Microscopic analyses revealed that root morphology was affected by metal exposure, and that the levels of trans-zeatin riboside, dihydrozeatin riboside, indole-3-acetic acid and the auxin/cytokinin ratio varied accordingly. By contrast, under metal treatments, minor modifications in gibberellic acid and abscisic acid levels occurred. Real-time polymerase chain reaction analysis of some genes involved in auxin and cytokinin synthesis (e.g. AtNIT in roots and AtIPT in shoots) showed on average a metal up-regulated transcription. The production of thiol-peptides was induced by all the metals, alone or in combination, and the expression of the genes involved in thiol-peptide synthesis (AtGSH1, AtGSH2, AtPCS1 and AtPCS2) was not stimulated by the metals, suggesting a full post-transcriptional control. Results show that the Cd/Cu/Zn-induced changes in root morphology are caused by a hormonal unbalance, mainly governed by the auxin/cytokinin ratio.
Collapse
Affiliation(s)
- Adriano Sofo
- School of Agricultural, Forestry, Food and Environmental Sciences, University of Basilicata, Viale dell'Ateneo Lucano, 10, I-85100, Potenza, Italy
| | - Antonella Vitti
- School of Agricultural, Forestry, Food and Environmental Sciences, University of Basilicata, Viale dell'Ateneo Lucano, 10, I-85100, Potenza, Italy
| | - Maria Nuzzaci
- School of Agricultural, Forestry, Food and Environmental Sciences, University of Basilicata, Viale dell'Ateneo Lucano, 10, I-85100, Potenza, Italy
| | - Giuseppe Tataranni
- School of Agricultural, Forestry, Food and Environmental Sciences, University of Basilicata, Viale dell'Ateneo Lucano, 10, I-85100, Potenza, Italy
| | - Antonio Scopa
- School of Agricultural, Forestry, Food and Environmental Sciences, University of Basilicata, Viale dell'Ateneo Lucano, 10, I-85100, Potenza, Italy
| | - Jaco Vangronsveld
- Environmental Biology Centre for Environmental Sciences, Hasselt University, B-3590, Diepenbeek, Belgium
| | - Tony Remans
- Environmental Biology Centre for Environmental Sciences, Hasselt University, B-3590, Diepenbeek, Belgium
| | - Giuseppina Falasca
- Department of Environmental Biology, "Sapienza" University of Rome, Piazzale A. Moro 5, I-00185, Rome, Italy
| | - Maria M Altamura
- Department of Environmental Biology, "Sapienza" University of Rome, Piazzale A. Moro 5, I-00185, Rome, Italy
| | - Francesca Degola
- Department of Life Sciences, University of Parma, Parco Area delle Scienze, I-43124, Parma, Italy
| | - Luigi Sanità di Toppi
- Department of Life Sciences, University of Parma, Parco Area delle Scienze, I-43124, Parma, Italy
| |
Collapse
|
43
|
Guan QL, Xing YH, Liu J, Wei WJ, Zhang R, Wang X, Bai FY. Application of multiple parallel perfused microbioreactors: Synthesis, characterization and cytotoxicity testing of the novel rare earth complexes with indole acid as a ligand. J Inorg Biochem 2013; 128:57-67. [DOI: 10.1016/j.jinorgbio.2013.07.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 07/02/2013] [Accepted: 07/08/2013] [Indexed: 12/20/2022]
|
44
|
Abstract
Auxin is a plant hormone involved in an extraordinarily broad variety of biological mechanisms. These range from basic cellular processes, such as endocytosis, cell polarity, and cell cycle control over localized responses such as cell elongation and differential growth, to macroscopic phenomena such as embryogenesis, tissue patterning, and de novo formation of organs. Even though the history of auxin research reaches back more than a hundred years, we are still far from a comprehensive understanding of how auxin governs such a wide range of responses. Some answers to this question may lie in the auxin molecule itself. Naturally occurring auxin-like substances have been found and they may play roles in specific developmental and cellular processes. The molecular mode of auxin action can be further explored by the utilization of synthetic auxin-like molecules. A second area is the perception of auxin, where we know of three seemingly independent receptors and signalling systems, some better understood than others, but each of them probably involved in distinct physiological processes. Lastly, auxin is actively modified, metabolized, and intracellularly compartmentalized, which can have a great impact on its availability and activity. In this review, we will give an overview of these rather recent and emerging areas of auxin research and try to formulate some of the open questions. Without doubt, the manifold facets of auxin biology will not cease to amaze us for a long time to come.
Collapse
Affiliation(s)
- Michael Sauer
- Centro Nacional de Biotecnología-CNB-CSIC, Darwin 3, 28049 Madrid, Spain
| | | | | |
Collapse
|
45
|
Korasick DA, Enders TA, Strader LC. Auxin biosynthesis and storage forms. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:2541-55. [PMID: 23580748 PMCID: PMC3695655 DOI: 10.1093/jxb/ert080] [Citation(s) in RCA: 292] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The plant hormone auxin drives plant growth and morphogenesis. The levels and distribution of the active auxin indole-3-acetic acid (IAA) are tightly controlled through synthesis, inactivation, and transport. Many auxin precursors and modified auxin forms, used to regulate auxin homeostasis, have been identified; however, very little is known about the integration of multiple auxin biosynthesis and inactivation pathways. This review discusses the many ways auxin levels are regulated through biosynthesis, storage forms, and inactivation, and the potential roles modified auxins play in regulating the bioactive pool of auxin to affect plant growth and development.
Collapse
Affiliation(s)
- David A. Korasick
- Department of Biology, Washington University in St. Louis, St Louis, MO 63130, USA
| | - Tara A. Enders
- Department of Biology, Washington University in St. Louis, St Louis, MO 63130, USA
| | - Lucia C. Strader
- Department of Biology, Washington University in St. Louis, St Louis, MO 63130, USA
| |
Collapse
|
46
|
Peer WA, Cheng Y, Murphy AS. Evidence of oxidative attenuation of auxin signalling. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:2629-39. [PMID: 23709674 DOI: 10.1093/jxb/ert152] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Indole-3-acetic acid (IAA) is the principle auxin in Arabidopsis and is synthesized primarily in meristems and nodes. Auxin is transported to distal parts of the plant in response to developmental programming or environmental stimuli to activate cell-specific responses. As with any signalling event, the signal must be attenuated to allow the system to reset. Local auxin accumulations are thus reduced by conjugation or catabolism when downstream responses have reached their optima. In most cell types, localized auxin accumulation increases both reactive oxygen species (ROS) and an irreversible catabolic product 2-oxindole-3-acid acid (oxIAA). oxIAA is inactive and does not induce expression of the auxin-responsive reporters DR5 or 2XD0. Here it is shown that oxIAA is not transported from cell to cell, although it appears to be a substrate for the ATP-binding cassette subfamily G (ABCG) transporters that are positioned primarily on the outer lateral surface of the root epidermis. However, oxIAA and oxIAA-Glc levels are higher in ABCB mutants that accumulate auxin due to defective cellular export. Auxin-induced ROS production appears to be at least partially mediated by the NAD(P)H oxidase RbohD. oxIAA levels are higher in mutants that lack ROS-scavenging flavonoids (tt4) and are lower in mutants that accumulate excess flavonols (tt3). These data suggest a model where IAA signalling is attenuated by IAA catabolism to oxIAA. Flavonoids appear to buffer ROS accumulations that occur with localized increases in IAA. This buffering of IAA oxidation would explain some growth responses observed in flavonoid-deficient mutants that cannot be explained by their established role in partially inhibiting auxin transport.
Collapse
Affiliation(s)
- Wendy Ann Peer
- Department of Environmental Science and Technology, University of Maryland, College Park, MD 20742, USA.
| | | | | |
Collapse
|
47
|
Abstract
Auxin plays important roles during the entire life span of a plant. This small organic acid influences cell division, cell elongation and cell differentiation, and has great impact on the final shape and function of cells and tissues in all higher plants. Auxin metabolism is not well understood but recent discoveries, reviewed here, have started to shed light on the processes that regulate the synthesis and degradation of this important plant hormone.
Collapse
Affiliation(s)
- Karin Ljung
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden.
| |
Collapse
|
48
|
Auxin and cytokinin metabolism and root morphological modifications in Arabidopsis thaliana seedlings infected with Cucumber mosaic virus (CMV) or exposed to cadmium. Int J Mol Sci 2013; 14:6889-902. [PMID: 23531542 PMCID: PMC3645669 DOI: 10.3390/ijms14046889] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 03/15/2013] [Accepted: 03/20/2013] [Indexed: 12/30/2022] Open
Abstract
Arabidopsis thaliana L. is a model plant but little information is available about morphological root changes as part of a phytohormonal common response against both biotic and abiotic stressors. For this purpose, two-week-old Arabidopsis seedlings were treated with 10 μM CdSO4 or infected with CMV. After 12 days the entire aerial parts and the root system were analyzed, and the presence of CMV or the accumulation of Cd were detected. Microscopic analysis revealed that both CMV and Cd influenced root morphology by a marked development in the length of root hairs and an intense root branching if compared to controls. Among the three treatments, Cd-treated seedlings showed a shorter root axis length and doubled their lateral root diameter, while the lateral roots of CMV-infected seedlings were the longest. The root growth patterns were accompanied by significant changes in the levels of indole-3-acetic acid, trans-zeatin riboside, dihydrozeatin riboside, as a probable consequence of the regulation of some genes involved in their biosynthesis/degradation. The opposite role on root development played by the phythormones studied is discussed in detail. The results obtained could provide insights into novel strategies for plant defense against pathogens and plant protection against pollutants.
Collapse
|
49
|
Barbez E, Kleine-Vehn J. Divide Et Impera--cellular auxin compartmentalization. CURRENT OPINION IN PLANT BIOLOGY 2013. [PMID: 23200033 DOI: 10.1016/j.pbi.2012.10.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The phytohormone auxin is an essential regulator for plant growth and development. Decades of intensive research revealed the mutual importance of auxin metabolism and intercellular cell-to-cell transport for the regulation of spatiotemporal auxin distribution. Just recently, intracellular putative auxin carriers, such as the PIN-FORMED (PIN)5/PIN8 and the PIN-LIKES (PILS)2/PILS5 were discovered at the endoplasmic reticulum (ER) and seem to limit nuclear auxin signaling via an auxin sequestration mechanism. Moreover, these auxin carriers at the ER might provide a link between auxin compartmentalization and auxin conjugation-based metabolism. Here we review the recent findings on auxin compartmentalization at the ER and discuss its potential contribution to cellular auxin homeostasis and its importance for plant development.
Collapse
Affiliation(s)
- Elke Barbez
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), 1190 Vienna, Austria
| | | |
Collapse
|
50
|
Novák O, Hényková E, Sairanen I, Kowalczyk M, Pospíšil T, Ljung K. Tissue-specific profiling of the Arabidopsis thaliana auxin metabolome. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 72:523-36. [PMID: 22725617 DOI: 10.1111/j.1365-313x.2012.05085.x] [Citation(s) in RCA: 181] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The plant hormone auxin is believed to influence almost every aspect of plant growth and development. Auxin transport, biosynthesis and degradation combine to form gradients of the hormone that influence a range of key developmental and environmental response processes. There is abundant genetic evidence for the existence of multiple pathways for auxin biosynthesis and degradation. The complexity of these pathways makes it difficult to obtain a clear picture of the relative importance of specific metabolic pathways during development. We have developed a sensitive mass spectrometry-based method to simultaneously profile the majority of known auxin precursors and conjugates/catabolites in small amounts of Arabidopsis tissue. The method includes a new derivatization technique for quantification of the most labile of the auxin precursors. We validated the method by profiling the auxin metabolome in root and shoot tissues from various Arabidopsis thaliana ecotypes and auxin over-producing mutant lines. Substantial differences were shown in metabolite patterns between the lines and tissues. We also found differences of several orders of magnitude in the abundance of auxin metabolites, potentially indicating the relative importance of these compounds in the maintenance of auxin levels and activity. The method that we have established will enable researchers to obtain a better understanding of the dynamics of auxin metabolism and activity during plant growth and development.
Collapse
Affiliation(s)
- Ondřej Novák
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-90183 Umeå, Sweden
| | | | | | | | | | | |
Collapse
|