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Cai Y, Ping H, Zhao J, Li C, Li Y, Liang G. IRON MAN interacts with Cu-DEFICIENCY INDUCED TRANSCRIPTION FACTOR 1 to maintain copper homeostasis. THE NEW PHYTOLOGIST 2024; 242:1206-1217. [PMID: 38031525 DOI: 10.1111/nph.19439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 11/06/2023] [Indexed: 12/01/2023]
Abstract
Copper (Cu) is essential for plant growth and development. IRON MAN (IMA) is a family of small peptides that can bind both iron (Fe) and Cu ions. It was reported that IMAs mediate Fe homeostasis in Arabidopsis thaliana. However, it remains unclear whether IMAs are involved in Cu homeostasis. The transcript abundance of IMA genes decreased in response to Cu deficiency. The combined disruption of all IMA genes caused enhanced tolerance to Cu deficiency and resulted in an increase in the transcript abundance of Cu uptake genes, whereas the overexpression of IMA1 or IMA3 led to the opposite results. Protein interaction assays indicated that IMAs interact with Cu-DEFICIENCY INDUCED TRANSCRIPTION FACTOR1 (CITF1), which is a positive regulator of the Cu uptake genes. Further studies showed that IMAs not only interfere with the DNA binding of CITF1 but also repress the transcriptional activation activity of CITF1, hence resulting in downregulation of the Cu uptake genes. Genetic analyses indicated that IMAs modulate Cu homeostasis in a CITF1-dependent manner. Our findings indicate that IMAs inhibit the functions of CITF1 in regulating Cu deficiency responses, thereby providing a conceptual framework for comprehending the regulation of Cu homeostasis.
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Affiliation(s)
- Yuerong Cai
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, 650223, China
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
| | - Huaqian Ping
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, 650223, China
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
| | - Junhui Zhao
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, 650223, China
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
| | - Chenyang Li
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, 650223, China
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
| | - Yang Li
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, 650223, China
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
| | - Gang Liang
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, 650223, China
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
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Abstract
Nutrients are scarce and valuable resources, so plants developed sophisticated mechanisms to optimize nutrient use efficiency. A crucial part of this is monitoring external and internal nutrient levels to adjust processes such as uptake, redistribution, and cellular compartmentation. Measurement of nutrient levels is carried out by primary sensors that typically involve either transceptors or transcription factors. Primary sensors are only now starting to be identified in plants for some nutrients. In particular, for nitrate, there is detailed insight concerning how the external nitrate status is sensed by members of the nitrate transporter 1 (NRT1) family. Potential sensors for other macronutrients such as potassium and sodium have also been identified recently, whereas for micronutrients such as zinc and iron, transcription factor type sensors have been reported. This review provides an overview that interprets and evaluates our current understanding of how plants sense macro and micronutrients in the rhizosphere and root symplast.
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Perea-García A, Puig S, Peñarrubia L. The role of post-transcriptional modulators of metalloproteins in response to metal deficiencies. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:1735-1750. [PMID: 34849747 DOI: 10.1093/jxb/erab521] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 11/25/2021] [Indexed: 06/13/2023]
Abstract
Copper and iron proteins have a wide range of functions in living organisms. Metal assembly into metalloproteins is a complex process, where mismetalation is detrimental and energy consuming to cells. Under metal deficiency, metal distribution is expected to reach a metalation ranking, prioritizing essential versus dispensable metalloproteins, while avoiding interference with other metals and protecting metal-sensitive processes. In this review, we propose that post-transcriptional modulators of metalloprotein mRNA (ModMeR) are good candidates in metal prioritization under metal-limited conditions. ModMeR target high quota or redundant metalloproteins and, by adjusting their synthesis, ModMeR act as internal metal distribution valves. Inappropriate metalation of ModMeR targets could compete with metal delivery to essential metalloproteins and interfere with metal-sensitive processes, such as chloroplastic photosynthesis and mitochondrial respiration. Regulation of ModMeR targets could increase or decrease the metal flow through interconnected pathways in cellular metal distribution, helping to achieve adequate differential metal requirements. Here, we describe and compare ModMeR that function in response to copper and iron deficiencies. Specifically, we describe copper-miRNAs from Arabidopsis thaliana and diverse iron ModMeR from yeast, mammals, and bacteria under copper and iron deficiencies, as well as the influence of oxidative stress. Putative functions derived from their role as ModMeR are also discussed.
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Affiliation(s)
- Ana Perea-García
- Departament de Bioquímica i Biologia Molecular and Institut Universitari de Biotecnologia i Biomedicina (BIOTECMED), Universitat de València, Burjassot, Valencia, Spain
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Paterna, Valencia, Spain
| | - Sergi Puig
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Paterna, Valencia, Spain
| | - Lola Peñarrubia
- Departament de Bioquímica i Biologia Molecular and Institut Universitari de Biotecnologia i Biomedicina (BIOTECMED), Universitat de València, Burjassot, Valencia, Spain
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Mancini E, Garcia-Molina A. Analysis of Alternative Splicing During the Combinatorial Response to Simultaneous Copper and Iron Deficiency in Arabidopsis Reveals Differential Events in Genes Involved in Amino Acid Metabolism. FRONTIERS IN PLANT SCIENCE 2022; 13:827828. [PMID: 35173758 PMCID: PMC8841432 DOI: 10.3389/fpls.2022.827828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 01/11/2022] [Indexed: 06/14/2023]
Abstract
Copper (Cu) and iron (Fe) constitute fundamental nutrients for plant biology but are often limited due to low bioavailability. Unlike responses to single Cu or Fe deprivation, the consequences of simultaneous Cu and Fe deficiency have not yet been fully deciphered. Previously, it was demonstrated that Cu and Fe deficiency applied in combination imposes transcriptome, proteome, and metabolome changes different from those triggered under each deficiency individually. Here, we evaluated the effect of alternative splicing (AS) on the transcriptome of rosette leaves under single and simultaneous Cu and Fe deficiency. Differentially spliced genes (DSGs) and differentially expressed genes (DEGs) coincided in number (2,600 approx.) although the overlapping fraction was minimal (15%). Functional annotation of changes exclusively detected under simultaneous Cu and Fe deficiency revealed that DEGs participated in general stress responses and translation, while DSGs were involved in metabolic reactions, especially amino acid biosynthesis. Interestingly, transcripts encoding central features for tryptophan (Trp) and asparagine (Asn) synthesis - two significantly altered metabolites under simultaneous Cu and Fe deficiency - underwent exclusive intron retention events under the double deficiency. However, transcript and protein amounts for these enzymes did not correlate with Trp and Asn concentration. In consequence, we propose that AS might act as a regulatory mechanism to modify the stability and/or functionality of the enzymes and therefore fine-tune amino acid production during the combinatorial response to simultaneous Cu and Fe deficiency.
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Affiliation(s)
| | - Antoni Garcia-Molina
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Barcelona, Spain
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Transcriptome Profiling of Cu Stressed Petunia Petals Reveals Candidate Genes Involved in Fe and Cu Crosstalk. Int J Mol Sci 2021; 22:ijms222111604. [PMID: 34769033 PMCID: PMC8583722 DOI: 10.3390/ijms222111604] [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: 09/19/2021] [Revised: 10/21/2021] [Accepted: 10/23/2021] [Indexed: 11/16/2022] Open
Abstract
Copper (Cu) is an essential element for most living plants, but it is toxic for plants when present in excess. To better understand the response mechanism under excess Cu in plants, especially in flowers, transcriptome sequencing on petunia buds and opened flowers under excess Cu was performed. Interestingly, the transcript level of FIT-independent Fe deficiency response genes was significantly affected in Cu stressed petals, probably regulated by basic-helix-loop-helix 121 (bHLH121), while no difference was found in Fe content. Notably, the expression level of bHLH121 was significantly down-regulated in petals under excess Cu. In addition, the expression level of genes related to photosystem II (PSII), photosystem I (PSI), cytochrome b6/f complex, the light-harvesting chlorophyll II complex and electron carriers showed disordered expression profiles in petals under excess Cu, thus photosynthesis parameters, including the maximum PSII efficiency (FV/FM), nonphotochemical quenching (NPQ), quantum yield of the PSII (ΦPS(II)) and photochemical quenching coefficient (qP), were reduced in Cu stressed petals. Moreover, the chlorophyll a content was significantly reduced, while the chlorophyll b content was not affected, probably caused by the increased expression of chlorophyllide a oxygenase (CAO). Together, we provide new insight into excess Cu response and the Cu–Fe crosstalk in flowers.
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Garcia-Molina A, Lehmann M, Schneider K, Klingl A, Leister D. Inactivation of cytosolic FUMARASE2 enhances growth and photosynthesis under simultaneous copper and iron deprivation in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:766-784. [PMID: 33583065 DOI: 10.1111/tpj.15199] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 01/22/2021] [Accepted: 02/10/2021] [Indexed: 05/29/2023]
Abstract
Copper (Cu) and iron (Fe) are essential for plant growth and are often in short supply under natural conditions. Molecular responses to simultaneous lack of both metals (-Cu-Fe) differ from those seen in the absence of either alone. Metabolome profiling of plant leaves previously revealed that fumarate levels fall under -Cu-Fe conditions. We employed lines lacking cytosolic FUMARASE2 (FUM2) activity to study the impact of constitutive suppression of cytosolic fumarate synthesis on plant growth under Cu and/or Fe deficiency. In fum2 mutants, photosynthesis and growth were less impaired under -Cu-Fe conditions than in wild-type (WT) seedlings. In particular, levels of photosynthetic proteins, chloroplast ultrastructure, amino acid profiles and redox state were less perturbed by simultaneous Cu-Fe deficiency in lines that cannot produce fumarate in the cytosol. Although cytosolic fumarate has been reported to promote acclimation of photosynthesis to low temperatures when metal supplies are adequate, the photosynthetic efficiency of fum2 lines grown under Cu-Fe deficiency in the cold was higher than in WT. Uptake and contents of Cu and Fe are similar in WT and fum2 plants under control and -Cu-Fe conditions, and lack of FUM2 does not alter the ability to sense metal deficiency, as indicated by marker gene expression. Collectively, we propose that reduced levels of cytosolic fumarate synthesis ultimately increase the availability of Fe for incorporation into metalloproteins.
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Affiliation(s)
- Antoni Garcia-Molina
- Faculty of Biology, Plant Molecular Biology, Ludwig-Maximilians-University Munich, Großhadernerstr. 2-4, Planegg-Martinsried, D-82152, Germany
| | - Martin Lehmann
- Faculty of Biology, Plant Molecular Biology, Ludwig-Maximilians-University Munich, Großhadernerstr. 2-4, Planegg-Martinsried, D-82152, Germany
| | - Katja Schneider
- Faculty of Biology, Plant Molecular Biology, Ludwig-Maximilians-University Munich, Großhadernerstr. 2-4, Planegg-Martinsried, D-82152, Germany
| | - Andreas Klingl
- Faculty of Biology, Plant Molecular Biology, Ludwig-Maximilians-University Munich, Großhadernerstr. 2-4, Planegg-Martinsried, D-82152, Germany
| | - Dario Leister
- Faculty of Biology, Plant Molecular Biology, Ludwig-Maximilians-University Munich, Großhadernerstr. 2-4, Planegg-Martinsried, D-82152, Germany
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Cai Y, Li Y, Liang G. FIT and bHLH Ib transcription factors modulate iron and copper crosstalk in Arabidopsis. PLANT, CELL & ENVIRONMENT 2021; 44:1679-1691. [PMID: 33464620 DOI: 10.1111/pce.14000] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 01/05/2021] [Accepted: 01/07/2021] [Indexed: 05/22/2023]
Abstract
Although the crosstalk between iron (Fe) and copper (Cu) homeostasis signalling networks exists in plants, the underlined molecular mechanism remains unclear. FIT (FER-LIKE IRON DEFICIENCY-INDUCED TRANSCRIPTION FACTOR) and four bHLH Ib members (bHLH38, bHLH39, bHLH100 and bHLH101) are the key regulators of Fe homeostasis. Here, we reveal that FIT and bHLH Ib control the up-regulation of Cu-uptake genes (COPT2, FRO4 and FRO5) by Fe deficiency, and Cu is required for improving plant growth under Fe-deficiency conditions. The induction of Cu-uptake gene expression and the elevation of Cu concentration are inhibited in the fit-2 or bhlh4x (the quadruple mutant of four bHLH Ib genes) under Fe-deficiency conditions. The dual overexpression of both bHLH38 (or bHLH39) and FIT activates the expression of COPT2, FRO4 and FRO5 and increases Cu accumulation. Furthermore, bHLH Ib proteins directly bind to the promoters of COPT2, FRO4 and FRO5. Either Cu supplement or overexpression of COPT2 or FRO4 improves the growth of fit-2 under Fe-deficiency conditions. Moreover, the induction of COPT2, FRO4 and FRO5 by Fe deficiency is independent of SPL7, a central regulator of Cu-deficiency responses. This work through the link between bHLH Ib/FIT and COPT2/FRO4/FRO5 under Fe-deficiency conditions establishes a new relationship between Cu and Fe homeostasis.
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Affiliation(s)
- Yuerong Cai
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Kunming, China
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, China
- The College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yang Li
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Kunming, China
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, China
| | - Gang Liang
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Kunming, China
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, China
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Kleine T, Nägele T, Neuhaus HE, Schmitz-Linneweber C, Fernie AR, Geigenberger P, Grimm B, Kaufmann K, Klipp E, Meurer J, Möhlmann T, Mühlhaus T, Naranjo B, Nickelsen J, Richter A, Ruwe H, Schroda M, Schwenkert S, Trentmann O, Willmund F, Zoschke R, Leister D. Acclimation in plants - the Green Hub consortium. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:23-40. [PMID: 33368770 DOI: 10.1111/tpj.15144] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 12/08/2020] [Accepted: 12/14/2020] [Indexed: 05/04/2023]
Abstract
Acclimation is the capacity to adapt to environmental changes within the lifetime of an individual. This ability allows plants to cope with the continuous variation in ambient conditions to which they are exposed as sessile organisms. Because environmental changes and extremes are becoming even more pronounced due to the current period of climate change, enhancing the efficacy of plant acclimation is a promising strategy for mitigating the consequences of global warming on crop yields. At the cellular level, the chloroplast plays a central role in many acclimation responses, acting both as a sensor of environmental change and as a target of cellular acclimation responses. In this Perspective article, we outline the activities of the Green Hub consortium funded by the German Science Foundation. The main aim of this research collaboration is to understand and strategically modify the cellular networks that mediate plant acclimation to adverse environments, employing Arabidopsis, tobacco (Nicotiana tabacum) and Chlamydomonas as model organisms. These efforts will contribute to 'smart breeding' methods designed to create crop plants with improved acclimation properties. To this end, the model oilseed crop Camelina sativa is being used to test modulators of acclimation for their potential to enhance crop yield under adverse environmental conditions. Here we highlight the current state of research on the role of gene expression, metabolism and signalling in acclimation, with a focus on chloroplast-related processes. In addition, further approaches to uncovering acclimation mechanisms derived from systems and computational biology, as well as adaptive laboratory evolution with photosynthetic microbes, are highlighted.
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Affiliation(s)
- Tatjana Kleine
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, 82152, Germany
| | - Thomas Nägele
- Plant Evolutionary Cell Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Munich, 82152, Germany
| | - H Ekkehard Neuhaus
- Plant Physiology, Department of Biology, Technische Universität Kaiserslautern, Kaiserslautern, 67663, Germany
| | | | - Alisdair R Fernie
- Central Metabolism, Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm, 14476, Germany
| | - Peter Geigenberger
- Plant Metabolism, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Munich, 82152, Germany
| | - Bernhard Grimm
- Plant Physiology, Institute of Biology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
| | - Kerstin Kaufmann
- Plant Cell and Molecular Biology, Institute of Biology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
| | - Edda Klipp
- Theoretical Biophysics, Institute of Biology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
| | - Jörg Meurer
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, 82152, Germany
| | - Torsten Möhlmann
- Plant Physiology, Department of Biology, Technische Universität Kaiserslautern, Kaiserslautern, 67663, Germany
| | - Timo Mühlhaus
- Computational Systems Biology, Department of Biology, Technische Universität Kaiserslautern, Kaiserslautern, 67663, Germany
| | - Belen Naranjo
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, 82152, Germany
| | - Jörg Nickelsen
- Molecular Plant Science, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Munich, 82152, Germany
| | - Andreas Richter
- Physiology of Plant Organelles, Institute of Biology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
| | - Hannes Ruwe
- Molecular Genetics, Institute of Biology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
| | - Michael Schroda
- Molecular Biotechnology & Systems Biology, Department of Biology, Technische Universität Kaiserslautern, Kaiserslautern, 67663, Germany
| | - Serena Schwenkert
- Plant Biochemistry and Physiology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Munich, 82152, Germany
| | - Oliver Trentmann
- Plant Physiology, Department of Biology, Technische Universität Kaiserslautern, Kaiserslautern, 67663, Germany
| | - Felix Willmund
- Molecular Genetics of Eukaryotes, Department of Biology, Technische Universität Kaiserslautern, Kaiserslautern, 67663, Germany
| | - Reimo Zoschke
- Translational Regulation in Plants, Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm, 14476, Germany
| | - Dario Leister
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, 82152, Germany
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Bernal M, Krämer U. Involvement of Arabidopsis Multi-Copper Oxidase-Encoding LACCASE12 in Root-to-Shoot Iron Partitioning: A Novel Example of Copper-Iron Crosstalk. FRONTIERS IN PLANT SCIENCE 2021; 12:688318. [PMID: 34707625 PMCID: PMC8544784 DOI: 10.3389/fpls.2021.688318] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 08/23/2021] [Indexed: 05/17/2023]
Abstract
Numerous central biological processes depend on the participation of the essential elements iron (Fe) or copper (Cu), including photosynthesis, respiration, cell wall remodeling and oxidative stress protection. Yet, both Fe and Cu metal cations can become toxic when accumulated in excess. Because of the potent ligand-binding and redox chemistries of these metals, there is a need for the tight and combined homeostatic control of their uptake and distribution. Several known examples pinpoint an inter-dependence of Fe and Cu homeostasis in eukaryotes, mostly in green algae, yeast and mammals, but this is less well understood in multicellular plants to date. In Arabidopsis, Cu deficiency causes secondary Fe deficiency, and this is associated with reduced in vitro ferroxidase activity and decreased root-to-shoot Fe translocation. Here we summarize the current knowledge of the cross-talk between Cu and Fe homeostasis and present a partial characterization of LACCASE12 (LAC12) that encodes a member of the multicopper oxidase (MCO) protein family in Arabidopsis. LAC12 transcript levels increase under Fe deficiency. The phenotypic characterization of two mutants carrying T-DNA insertions suggests a role of LAC12 in root-to-shoot Fe partitioning and in maintaining growth on Fe-deficient substrates. A molecular understanding of the complex interactions between Fe and Cu will be important for combating Fe deficiency in crops and for advancing biofortification approaches.
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Affiliation(s)
- María Bernal
- Department of Molecular Genetics and Physiology of Plants, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
- Department of Plant Nutrition, Estación Experimental de Aula Dei-CSIC, Zaragoza, Spain
- *Correspondence: María Bernal,
| | - Ute Krämer
- Department of Molecular Genetics and Physiology of Plants, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
- Ute Krämer,
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