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Montillet JL, Rondet D, Brugière S, Henri P, Rumeau D, Reichheld JP, Couté Y, Leonhardt N, Rey P. Plastidial and cytosolic thiol reductases participate in the control of stomatal functioning. Plant Cell Environ 2021; 44:1417-1435. [PMID: 33537988 DOI: 10.1111/pce.14013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 01/08/2021] [Accepted: 01/11/2021] [Indexed: 06/12/2023]
Abstract
Stomatal movements via the control of gas exchanges determine plant growth in relation to environmental stimuli through a complex signalling network involving reactive oxygen species that lead to post-translational modifications of Cys and Met residues, and alter protein activity and/or conformation. Thiol-reductases (TRs), which include thioredoxins, glutaredoxins (GRXs) and peroxiredoxins (PRXs), participate in signalling pathways through the control of Cys redox status in client proteins. Their involvement in stomatal functioning remains poorly characterized. By performing a mass spectrometry-based proteomic analysis, we show that numerous thiol reductases, like PRXs, are highly abundant in guard cells. When investigating various Arabidopsis mutants impaired in the expression of TR genes, no change in stomatal density and index was noticed. In optimal growth conditions, a line deficient in cytosolic NADPH-thioredoxin reductases displayed higher stomatal conductance and lower leaf temperature evaluated by thermal infrared imaging. In contrast, lines deficient in plastidial 2-CysPRXs or type-II GRXs exhibited compared to WT reduced conductance and warmer leaves in optimal conditions, and enhanced stomatal closure in epidermal peels treated with abscisic acid or hydrogen peroxide. Altogether, these data strongly support the contribution of thiol redox switches within the signalling network regulating guard cell movements and stomatal functioning.
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Affiliation(s)
- Jean-Luc Montillet
- Plant Protective Proteins Team, Aix Marseille University, CEA, CNRS, BIAM, Saint Paul-Lez-Durance, France
| | - Damien Rondet
- Plant Protective Proteins Team, Aix Marseille University, CEA, CNRS, BIAM, Saint Paul-Lez-Durance, France
- Laboratoire Nixe, Sophia-Antipolis, Valbonne, France
| | - Sabine Brugière
- Laboratoire EDyP, University of Grenoble Alpes, CEA, INSERM, IRIG, BGE, Grenoble, France
| | - Patricia Henri
- Plant Protective Proteins Team, Aix Marseille University, CEA, CNRS, BIAM, Saint Paul-Lez-Durance, France
| | - Dominique Rumeau
- Plant Protective Proteins Team, Aix Marseille University, CEA, CNRS, BIAM, Saint Paul-Lez-Durance, France
| | - Jean-Philippe Reichheld
- Laboratoire Génome et Développement des Plantes, CNRS, Université Perpignan Via Domitia, Perpignan, France
| | - Yohann Couté
- Laboratoire EDyP, University of Grenoble Alpes, CEA, INSERM, IRIG, BGE, Grenoble, France
| | - Nathalie Leonhardt
- SAVE Team, Aix Marseille University, CEA, CNRS, BIAM, Saint Paul-Lez-Durance, France
| | - Pascal Rey
- Plant Protective Proteins Team, Aix Marseille University, CEA, CNRS, BIAM, Saint Paul-Lez-Durance, France
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Henri P, Rumeau D. Ectopic expression of human apolipoprotein D in Arabidopsis plants lacking chloroplastic lipocalin partially rescues sensitivity to drought and oxidative stress. Plant Physiol Biochem 2021; 158:265-274. [PMID: 33262014 DOI: 10.1016/j.plaphy.2020.11.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 11/09/2020] [Indexed: 06/12/2023]
Abstract
The chloroplastic lipocalin (LCNP) is induced in response to various abiotic stresses including high light, dehydration and low temperature. It contributes to protection against oxidative damage promoted by adverse conditions by preventing accumulation of fatty acid hydroperoxides and lipid peroxidation. In contrast to animal lipocalins, LCNP is poorly characterized and the molecular mechanism by which it exerts protective effects during oxidative stress is largely unknown. LCNP is considered the ortholog of human apolipoprotein D (APOD), a protein whose lipid antioxidant function has been characterized. Here, we investigated whether APOD could functionally replace LCNP in Arabidopsis thaliana. We introduced APOD cDNA fused to a chloroplast transit peptide encoding sequence in an Arabidopsis LCNP KO mutant line and challenged the transgenic plants with different abiotic stresses. We demonstrated that expression of human APOD in Arabidopsis can partially compensate for the lack of the plastid lipocalin. The results are consistent with a conserved function of APOD and LCNP under stressful conditions. However, if the results obtained with the drought and oxidative stresses point to the protective effect of constitutive expression of APOD in plants lacking LCNP, this effect is not as effective as that conferred by LCNP overexpression. Moreover, when investigating APOD function in thylakoids after high light stress at low temperature, it appeared that APOD could not contribute to qH, a slowly reversible form of non-photochemical chlorophyll fluorescence quenching, as described for LCNP. This work provides a base of understanding the molecular mechanism underlying LCNP protective function.
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Affiliation(s)
- Patricia Henri
- Aix-Marseille Université, CEA, CNRS, UMR 7265, Institut Biosciences et Biotechnologies d'Aix-Marseille, Plant Protein Protection Laboratory, CEA/Cadarache, F-13108, Saint-Paul-lez-Durance, France
| | - Dominique Rumeau
- Aix-Marseille Université, CEA, CNRS, UMR 7265, Institut Biosciences et Biotechnologies d'Aix-Marseille, Plant Protein Protection Laboratory, CEA/Cadarache, F-13108, Saint-Paul-lez-Durance, France.
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Malnoë A, Schultink A, Shahrasbi S, Rumeau D, Havaux M, Niyogi KK. The Plastid Lipocalin LCNP Is Required for Sustained Photoprotective Energy Dissipation in Arabidopsis. Plant Cell 2018; 30:196-208. [PMID: 29233855 PMCID: PMC5810567 DOI: 10.1105/tpc.17.00536] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 11/01/2017] [Accepted: 12/08/2017] [Indexed: 05/18/2023]
Abstract
Light utilization is finely tuned in photosynthetic organisms to prevent cellular damage. The dissipation of excess absorbed light energy, a process termed nonphotochemical quenching (NPQ), plays an important role in photoprotection. Little is known about the sustained or slowly reversible form(s) of NPQ and whether they are photoprotective, in part due to the lack of mutants. The Arabidopsis thaliana suppressor of quenching1 (soq1) mutant exhibits enhanced sustained NPQ, which we term qH. To identify molecular players involved in qH, we screened for suppressors of soq1 and isolated mutants affecting either chlorophyllide a oxygenase or the chloroplastic lipocalin, now renamed plastid lipocalin (LCNP). Analysis of the mutants confirmed that qH is localized to the peripheral antenna (LHCII) of photosystem II and demonstrated that LCNP is required for qH, either directly (by forming NPQ sites) or indirectly (by modifying the LHCII membrane environment). qH operates under stress conditions such as cold and high light and is photoprotective, as it reduces lipid peroxidation levels. We propose that, under stress conditions, LCNP protects the thylakoid membrane by enabling sustained NPQ in LHCII, thereby preventing singlet oxygen stress.
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Affiliation(s)
- Alizée Malnoë
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Alex Schultink
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720
| | - Sanya Shahrasbi
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720
| | - Dominique Rumeau
- CEA, CNRS UMR 7265, Biologie Végétale et Microbiologie Environnementales, Aix-Marseille Université, Laboratoire d'Ecophysiologie Moléculaire des Plantes, Saint-Paul-lez-Durance 13108, France
| | - Michel Havaux
- CEA, CNRS UMR 7265, Biologie Végétale et Microbiologie Environnementales, Aix-Marseille Université, Laboratoire d'Ecophysiologie Moléculaire des Plantes, Saint-Paul-lez-Durance 13108, France
| | - Krishna K Niyogi
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720
- Howard Hughes Medical Institute, University of California, Berkeley, California 94720
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Montillet JL, Leonhardt N, Mondy S, Tranchimand S, Rumeau D, Boudsocq M, Garcia AV, Douki T, Bigeard J, Laurière C, Chevalier A, Castresana C, Hirt H. An abscisic acid-independent oxylipin pathway controls stomatal closure and immune defense in Arabidopsis. PLoS Biol 2013; 11:e1001513. [PMID: 23526882 PMCID: PMC3602010 DOI: 10.1371/journal.pbio.1001513] [Citation(s) in RCA: 189] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Accepted: 02/07/2013] [Indexed: 11/19/2022] Open
Abstract
In Arabidopsis the stomatal defense response, a feature of the innate immunity in plants, involves oxylipin-mediated mechanisms that are independent of the phytohormone abscisic acid. Plant stomata function in innate immunity against bacterial invasion and abscisic acid (ABA) has been suggested to regulate this process. Using genetic, biochemical, and pharmacological approaches, we demonstrate that (i) the Arabidopsis thaliana nine-specific-lipoxygenase encoding gene, LOX1, which is expressed in guard cells, is required to trigger stomatal closure in response to both bacteria and the pathogen-associated molecular pattern flagellin peptide flg22; (ii) LOX1 participates in stomatal defense; (iii) polyunsaturated fatty acids, the LOX substrates, trigger stomatal closure; (iv) the LOX products, fatty acid hydroperoxides, or reactive electrophile oxylipins induce stomatal closure; and (v) the flg22-mediated stomatal closure is conveyed by both LOX1 and the mitogen-activated protein kinases MPK3 and MPK6 and involves salicylic acid whereas the ABA-induced process depends on the protein kinases OST1, MPK9, or MPK12. Finally, we show that the oxylipin and the ABA pathways converge at the level of the anion channel SLAC1 to regulate stomatal closure. Collectively, our results demonstrate that early biotic signaling in guard cells is an ABA-independent process revealing a novel function of LOX1-dependent stomatal pathway in plant immunity. Stomata are microscopic pores that are present in the epidermis of the aerial parts of higher plants, such as the leaves. These pores, which are flanked by a pair of cells called guard cells, regulate transpiration and the exchange of gas between leaves and the atmosphere. It is well documented that the phytohormone abscisic acid (ABA) is a key regulator that controls the osmotic pressure in guard cells, allowing pore size to be adjusted in response to environmental conditions. Recently, stomata have also been shown to play an important role in the innate immune response. Indeed, upon contact with microbes, plants actively close stomata to prevent the entry of microbes and the consequent colonization of host tissue. This response is known as the stomatal defense response. However, the molecular mechanisms that regulate this defense response are not well understood. Using a variety of approaches, we show in this study that LOX1, a gene that encodes lipoxygenase (LOX) in guard cells, plays a major role in stomatal defense in the model plant Arabidopsis thaliana. Mutations in LOX1 impair stomatal closure and make plants more susceptible to the bacterium Pseudomonas syringae pv. tomato. We also show that several LOX-derived metabolites, the oxylipins, are potent inducers of stomatal closure. Finally, we provide evidence to show that ABA plays only a minor role in stomatal defense response, specifically by modulating this response.
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Affiliation(s)
- Jean-Luc Montillet
- CEA Cadarache, Direction des Sciences du Vivant, Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et de Microbiologie Environnementale, Laboratoire d'Ecophysiologie Moléculaire des Plantes, Unité Mixte de Recherche 7265, Centre National de la Recherche Scientifique/Commissariat à l'Energie Atomique/Aix-Marseille Université, Saint-Paul-lez-Durance, France.
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Laugier E, Tarrago L, Courteille A, Innocenti G, Eymery F, Rumeau D, Issakidis-Bourguet E, Rey P. Involvement of thioredoxin y2 in the preservation of leaf methionine sulfoxide reductase capacity and growth under high light. Plant Cell Environ 2013; 36:670-82. [PMID: 22943306 DOI: 10.1111/pce.12005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Methionine (Met) in proteins can be oxidized to two diastereoisomers of methionine sulfoxide, Met-S-O and Met-R-O, which are reduced back to Met by two types of methionine sulfoxide reductases (MSRs), A and B, respectively. MSRs are generally supplied with reducing power by thioredoxins. Plants are characterized by a large number of thioredoxin isoforms, but those providing electrons to MSRs in vivo are not known. Three MSR isoforms, MSRA4, MSRB1 and MSRB2, are present in Arabidopsis thaliana chloroplasts. Under conditions of high light and long photoperiod, plants knockdown for each plastidial MSR type or for both display reduced growth. In contrast, overexpression of plastidial MSRBs is not associated with beneficial effects in terms of growth under high light. To identify the physiological reductants for plastidial MSRs, we analyzed a series of mutants deficient for thioredoxins f, m, x or y. We show that mutant lines lacking both thioredoxins y1 and y2 or only thioredoxin y2 specifically display a significantly reduced leaf MSR capacity (-25%) and growth characteristics under high light, related to those of plants lacking plastidial MSRs. We propose that thioredoxin y2 plays a physiological function in protein repair mechanisms as an electron donor to plastidial MSRs in photosynthetic organs.
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Affiliation(s)
- Edith Laugier
- CEA, DSV, IBEB, Lab Ecophysiol Molecul Plantes, Saint-Paul-lez-Durance, F-13108, France
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Rey P, Sanz-Barrio R, Innocenti G, Ksas B, Courteille A, Rumeau D, Issakidis-Bourguet E, Farran I. Overexpression of plastidial thioredoxins f and m differentially alters photosynthetic activity and response to oxidative stress in tobacco plants. Front Plant Sci 2013; 4:390. [PMID: 24137166 PMCID: PMC3797462 DOI: 10.3389/fpls.2013.00390] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 09/12/2013] [Indexed: 05/07/2023]
Abstract
Plants display a remarkable diversity of thioredoxins (Trxs), reductases controlling the thiol redox status of proteins. The physiological function of many of them remains elusive, particularly for plastidial Trxs f and m, which are presumed based on biochemical data to regulate photosynthetic reactions and carbon metabolism. Recent reports revealed that Trxs f and m participate in vivo in the control of starch metabolism and cyclic photosynthetic electron transfer around photosystem I, respectively. To further delineate their in planta function, we compared the photosynthetic characteristics, the level and/or activity of various Trx targets and the responses to oxidative stress in transplastomic tobacco plants overexpressing either Trx f or Trx m. We found that plants overexpressing Trx m specifically exhibit altered growth, reduced chlorophyll content, impaired photosynthetic linear electron transfer and decreased pools of glutathione and ascorbate. In both transplastomic lines, activities of two enzymes involved in carbon metabolism, NADP-malate dehydrogenase and NADP-glyceraldehyde-3-phosphate dehydrogenase are markedly and similarly altered. In contrast, plants overexpressing Trx m specifically display increased capacity for methionine sulfoxide reductases, enzymes repairing damaged proteins by regenerating methionine from oxidized methionine. Finally, we also observed that transplastomic plants exhibit distinct responses when exposed to oxidative stress conditions generated by methyl viologen or exposure to high light combined with low temperature, the plants overexpressing Trx m being notably more tolerant than Wt and those overexpressing Trx f. Altogether, these data indicate that Trxs f and m fulfill distinct physiological functions. They prompt us to propose that the m type is involved in key processes linking photosynthetic activity, redox homeostasis and antioxidant mechanisms in the chloroplast.
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Affiliation(s)
- Pascal Rey
- Laboratoire d’Ecophysiologie Moléculaire des Plantes, Institut de Biologie Environnementale et Biotechnologie, Direction des Sciences du Vivant, Commissariat à l’Energie AtomiqueSaint-Paul-lez-Durance, France
- UMR 7265 Service de Biologie Végétale et de Microbiologie Environnementales, Centre National de la Recherche ScientifiqueSaint-Paul-lez-Durance, France
- Aix-Marseille Université Saint-Paul-lez-Durance, France
- *Correspondence: Pascal Rey, Laboratoire d’Ecophysiologie Moléculaire des Plantes, Institut de Biologie Environnementale et Biotechnologie, Direction des Sciences du Vivant, Commissariat à l’Energie Atomique, Bâtiment 158, SBVME, CEA-Cadarache, 13108 Saint-Paul-Lez-Durance Cedex, France e-mail:
| | - Ruth Sanz-Barrio
- Instituto de Agrobiotecnología, Universidad Pública de Navarra-Consejo Superior de Investigaciones CientíficasPamplona, Spain
| | - Gilles Innocenti
- UMR 8618 Institut de Biologie des Plantes, Centre National de la Recherche Scientifique, Université Paris-SudOrsay, France
| | - Brigitte Ksas
- Laboratoire d’Ecophysiologie Moléculaire des Plantes, Institut de Biologie Environnementale et Biotechnologie, Direction des Sciences du Vivant, Commissariat à l’Energie AtomiqueSaint-Paul-lez-Durance, France
- UMR 7265 Service de Biologie Végétale et de Microbiologie Environnementales, Centre National de la Recherche ScientifiqueSaint-Paul-lez-Durance, France
- Aix-Marseille Université Saint-Paul-lez-Durance, France
| | - Agathe Courteille
- Laboratoire d’Ecophysiologie Moléculaire des Plantes, Institut de Biologie Environnementale et Biotechnologie, Direction des Sciences du Vivant, Commissariat à l’Energie AtomiqueSaint-Paul-lez-Durance, France
- UMR 7265 Service de Biologie Végétale et de Microbiologie Environnementales, Centre National de la Recherche ScientifiqueSaint-Paul-lez-Durance, France
- Aix-Marseille Université Saint-Paul-lez-Durance, France
| | - Dominique Rumeau
- Laboratoire d’Ecophysiologie Moléculaire des Plantes, Institut de Biologie Environnementale et Biotechnologie, Direction des Sciences du Vivant, Commissariat à l’Energie AtomiqueSaint-Paul-lez-Durance, France
- UMR 7265 Service de Biologie Végétale et de Microbiologie Environnementales, Centre National de la Recherche ScientifiqueSaint-Paul-lez-Durance, France
- Aix-Marseille Université Saint-Paul-lez-Durance, France
| | - Emmanuelle Issakidis-Bourguet
- UMR 8618 Institut de Biologie des Plantes, Centre National de la Recherche Scientifique, Université Paris-SudOrsay, France
| | - Inmaculada Farran
- Instituto de Agrobiotecnología, Universidad Pública de Navarra-Consejo Superior de Investigaciones CientíficasPamplona, Spain
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Montillet JL, Leonhardt N, Mondy S, Tranchimand S, Rumeau D, Boudsocq M, Garcia AV, Douki T, Bigeard J, Laurière C, Chevalier A, Castresana C, Hirt H. An abscisic acid-independent oxylipin pathway controls stomatal closure and immune defense in Arabidopsis. PLoS Biol 2013; 11:e1001513. [PMID: 23526882 DOI: 10.3410/f.717991704.793474995] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Accepted: 02/07/2013] [Indexed: 05/22/2023] Open
Abstract
Plant stomata function in innate immunity against bacterial invasion and abscisic acid (ABA) has been suggested to regulate this process. Using genetic, biochemical, and pharmacological approaches, we demonstrate that (i) the Arabidopsis thaliana nine-specific-lipoxygenase encoding gene, LOX1, which is expressed in guard cells, is required to trigger stomatal closure in response to both bacteria and the pathogen-associated molecular pattern flagellin peptide flg22; (ii) LOX1 participates in stomatal defense; (iii) polyunsaturated fatty acids, the LOX substrates, trigger stomatal closure; (iv) the LOX products, fatty acid hydroperoxides, or reactive electrophile oxylipins induce stomatal closure; and (v) the flg22-mediated stomatal closure is conveyed by both LOX1 and the mitogen-activated protein kinases MPK3 and MPK6 and involves salicylic acid whereas the ABA-induced process depends on the protein kinases OST1, MPK9, or MPK12. Finally, we show that the oxylipin and the ABA pathways converge at the level of the anion channel SLAC1 to regulate stomatal closure. Collectively, our results demonstrate that early biotic signaling in guard cells is an ABA-independent process revealing a novel function of LOX1-dependent stomatal pathway in plant immunity.
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Affiliation(s)
- Jean-Luc Montillet
- CEA Cadarache, Direction des Sciences du Vivant, Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et de Microbiologie Environnementale, Laboratoire d'Ecophysiologie Moléculaire des Plantes, Unité Mixte de Recherche 7265, Centre National de la Recherche Scientifique/Commissariat à l'Energie Atomique/Aix-Marseille Université, Saint-Paul-lez-Durance, France.
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Courteille A, Vesa S, Sanz-Barrio R, Cazalé AC, Becuwe-Linka N, Farran I, Havaux M, Rey P, Rumeau D. Thioredoxin m4 controls photosynthetic alternative electron pathways in Arabidopsis. Plant Physiol 2013; 161:508-20. [PMID: 23151348 PMCID: PMC3532281 DOI: 10.1104/pp.112.207019] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 11/12/2012] [Indexed: 05/18/2023]
Abstract
In addition to the linear electron flow, a cyclic electron flow (CEF) around photosystem I occurs in chloroplasts. In CEF, electrons flow back from the donor site of photosystem I to the plastoquinone pool via two main routes: one that involves the Proton Gradient Regulation5 (PGR5)/PGRL1 complex (PGR) and one that is dependent of the NADH dehydrogenase-like complex. While the importance of CEF in photosynthesis and photoprotection has been clearly established, little is known about its regulation. We worked on the assumption of a redox regulation and surveyed the putative role of chloroplastic thioredoxins (TRX). Using Arabidopsis (Arabidopsis thaliana) mutants lacking different TRX isoforms, we demonstrated in vivo that TRXm4 specifically plays a role in the down-regulation of the NADH dehydrogenase-like complex-dependent plastoquinone reduction pathway. This result was confirmed in tobacco (Nicotiana tabacum) plants overexpressing the TRXm4 orthologous gene. In vitro assays performed with isolated chloroplasts and purified TRXm4 indicated that TRXm4 negatively controls the PGR pathway as well. The physiological significance of this regulation was investigated under steady-state photosynthesis and in the pgr5 mutant background. Lack of TRXm4 reversed the growth phenotype of the pgr5 mutant, but it did not compensate for the impaired photosynthesis and photoinhibition sensitivity. This suggests that the physiological role of TRXm4 occurs in vivo via a mechanism distinct from direct up-regulation of CEF.
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Affiliation(s)
| | | | - Ruth Sanz-Barrio
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7265, Biologie Végétale et Microbiologie Environnementales, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Commissariat à l'Energie Atomique, Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et Microbiologie Environnementales, Laboratoire d’Ecophysiologie Moléculaire des Plantes, 13108 Saint-Paul-lez-Durance, France (S.V., N.B.-L., M.H., P.R., D.R.); Université Aix-Marseille, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Instituto de Agrobiotecnologia, Universidad Pública de Navarra-Consejo Superior de Investigaciones Científicas-Gobierno de Navarra, 31006 Pamplona, Spain (R.S.-B., I.F.); Institut National de la Recherche Agronomique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 441, F-31326 Castanet-Tolosan, France (A.-C.C.); and Centre National de la Recherche Scientifique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 2594, F-31326 Castanet-Tolosan, France (A.-C.C.)
| | - Anne-Claire Cazalé
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7265, Biologie Végétale et Microbiologie Environnementales, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Commissariat à l'Energie Atomique, Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et Microbiologie Environnementales, Laboratoire d’Ecophysiologie Moléculaire des Plantes, 13108 Saint-Paul-lez-Durance, France (S.V., N.B.-L., M.H., P.R., D.R.); Université Aix-Marseille, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Instituto de Agrobiotecnologia, Universidad Pública de Navarra-Consejo Superior de Investigaciones Científicas-Gobierno de Navarra, 31006 Pamplona, Spain (R.S.-B., I.F.); Institut National de la Recherche Agronomique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 441, F-31326 Castanet-Tolosan, France (A.-C.C.); and Centre National de la Recherche Scientifique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 2594, F-31326 Castanet-Tolosan, France (A.-C.C.)
| | - Noëlle Becuwe-Linka
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7265, Biologie Végétale et Microbiologie Environnementales, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Commissariat à l'Energie Atomique, Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et Microbiologie Environnementales, Laboratoire d’Ecophysiologie Moléculaire des Plantes, 13108 Saint-Paul-lez-Durance, France (S.V., N.B.-L., M.H., P.R., D.R.); Université Aix-Marseille, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Instituto de Agrobiotecnologia, Universidad Pública de Navarra-Consejo Superior de Investigaciones Científicas-Gobierno de Navarra, 31006 Pamplona, Spain (R.S.-B., I.F.); Institut National de la Recherche Agronomique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 441, F-31326 Castanet-Tolosan, France (A.-C.C.); and Centre National de la Recherche Scientifique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 2594, F-31326 Castanet-Tolosan, France (A.-C.C.)
| | - Immaculada Farran
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7265, Biologie Végétale et Microbiologie Environnementales, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Commissariat à l'Energie Atomique, Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et Microbiologie Environnementales, Laboratoire d’Ecophysiologie Moléculaire des Plantes, 13108 Saint-Paul-lez-Durance, France (S.V., N.B.-L., M.H., P.R., D.R.); Université Aix-Marseille, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Instituto de Agrobiotecnologia, Universidad Pública de Navarra-Consejo Superior de Investigaciones Científicas-Gobierno de Navarra, 31006 Pamplona, Spain (R.S.-B., I.F.); Institut National de la Recherche Agronomique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 441, F-31326 Castanet-Tolosan, France (A.-C.C.); and Centre National de la Recherche Scientifique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 2594, F-31326 Castanet-Tolosan, France (A.-C.C.)
| | - Michel Havaux
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7265, Biologie Végétale et Microbiologie Environnementales, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Commissariat à l'Energie Atomique, Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et Microbiologie Environnementales, Laboratoire d’Ecophysiologie Moléculaire des Plantes, 13108 Saint-Paul-lez-Durance, France (S.V., N.B.-L., M.H., P.R., D.R.); Université Aix-Marseille, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Instituto de Agrobiotecnologia, Universidad Pública de Navarra-Consejo Superior de Investigaciones Científicas-Gobierno de Navarra, 31006 Pamplona, Spain (R.S.-B., I.F.); Institut National de la Recherche Agronomique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 441, F-31326 Castanet-Tolosan, France (A.-C.C.); and Centre National de la Recherche Scientifique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 2594, F-31326 Castanet-Tolosan, France (A.-C.C.)
| | - Pascal Rey
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7265, Biologie Végétale et Microbiologie Environnementales, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Commissariat à l'Energie Atomique, Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et Microbiologie Environnementales, Laboratoire d’Ecophysiologie Moléculaire des Plantes, 13108 Saint-Paul-lez-Durance, France (S.V., N.B.-L., M.H., P.R., D.R.); Université Aix-Marseille, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Instituto de Agrobiotecnologia, Universidad Pública de Navarra-Consejo Superior de Investigaciones Científicas-Gobierno de Navarra, 31006 Pamplona, Spain (R.S.-B., I.F.); Institut National de la Recherche Agronomique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 441, F-31326 Castanet-Tolosan, France (A.-C.C.); and Centre National de la Recherche Scientifique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 2594, F-31326 Castanet-Tolosan, France (A.-C.C.)
| | - Dominique Rumeau
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7265, Biologie Végétale et Microbiologie Environnementales, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Commissariat à l'Energie Atomique, Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et Microbiologie Environnementales, Laboratoire d’Ecophysiologie Moléculaire des Plantes, 13108 Saint-Paul-lez-Durance, France (S.V., N.B.-L., M.H., P.R., D.R.); Université Aix-Marseille, 13108 Saint-Paul-lez-Durance, France (A.C., S.V., N.B.-L., M.H., P.R., D.R.); Instituto de Agrobiotecnologia, Universidad Pública de Navarra-Consejo Superior de Investigaciones Científicas-Gobierno de Navarra, 31006 Pamplona, Spain (R.S.-B., I.F.); Institut National de la Recherche Agronomique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 441, F-31326 Castanet-Tolosan, France (A.-C.C.); and Centre National de la Recherche Scientifique, Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche 2594, F-31326 Castanet-Tolosan, France (A.-C.C.)
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Nashilevitz S, Melamed-Bessudo C, Izkovich Y, Rogachev I, Osorio S, Itkin M, Adato A, Pankratov I, Hirschberg J, Fernie AR, Wolf S, Usadel B, Levy AA, Rumeau D, Aharoni A. An orange ripening mutant links plastid NAD(P)H dehydrogenase complex activity to central and specialized metabolism during tomato fruit maturation. Plant Cell 2010; 22:1977-97. [PMID: 20571113 PMCID: PMC2910969 DOI: 10.1105/tpc.110.074716] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2010] [Revised: 05/14/2010] [Accepted: 06/07/2010] [Indexed: 05/18/2023]
Abstract
In higher plants, the plastidial NADH dehydrogenase (Ndh) complex supports nonphotochemical electron fluxes from stromal electron donors to plastoquinones. Ndh functions in chloroplasts are not clearly established; however, its activity was linked to the prevention of the overreduction of stroma, especially under stress conditions. Here, we show by the characterization of Orr(Ds), a dominant transposon-tagged tomato (Solanum lycopersicum) mutant deficient in the NDH-M subunit, that this complex is also essential for the fruit ripening process. Alteration to the NDH complex in fruit changed the climacteric, ripening-associated metabolites and transcripts as well as fruit shelf life. Metabolic processes in chromoplasts of ripening tomato fruit were affected in Orr(Ds), as mutant fruit were yellow-orange and accumulated substantially less total carotenoids, mainly beta-carotene and lutein. The changes in carotenoids were largely influenced by environmental conditions and accompanied by modifications in levels of other fruit antioxidants, namely, flavonoids and tocopherols. In contrast with the pigmentation phenotype in mature mutant fruit, Orr(Ds) leaves and green fruits did not display a visible phenotype but exhibited reduced Ndh complex quantity and activity. This study therefore paves the way for further studies on the role of electron transport and redox reactions in the regulation of fruit ripening and its associated metabolism.
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Affiliation(s)
- Shai Nashilevitz
- Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
- Faculty of Agricultural, Food, and Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | | | - Yinon Izkovich
- Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ilana Rogachev
- Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sonia Osorio
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| | - Maxim Itkin
- Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Avital Adato
- Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ilya Pankratov
- Department of Genetics, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Joseph Hirschberg
- Department of Genetics, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Alisdair R. Fernie
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| | - Shmuel Wolf
- Faculty of Agricultural, Food, and Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Björn Usadel
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| | - Avraham A. Levy
- Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Dominique Rumeau
- Commissariat à l'Energie Atomique Cadarache, Direction des Sciences du Vivant, Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et de Microbiologie Environnementale, Laboratoire d'Ecophysiologie Moléculaire des Plantes, Unité Mixte de Recherche 6191, Centre National de la Recherche Scientifique/Commissariat à l'Energie Atomique/Université de la Méditerranée, F-13108 Saint-Paul-lez-Durance, France
| | - Asaph Aharoni
- Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
- Address correspondence to
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10
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Munekage YN, Eymery F, Rumeau D, Cuiné S, Oguri M, Nakamura N, Yokota A, Genty B, Peltier G. Elevated Expression of PGR5 and NDH-H in Bundle Sheath Chloroplasts in C4Flaveria Species. ACTA ACUST UNITED AC 2010; 51:664-8. [DOI: 10.1093/pcp/pcq030] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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11
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Havaux M, Ksas B, Szewczyk A, Rumeau D, Franck F, Caffarri S, Triantaphylidès C. Vitamin B6 deficient plants display increased sensitivity to high light and photo-oxidative stress. BMC Plant Biol 2009; 9:130. [PMID: 19903353 PMCID: PMC2777905 DOI: 10.1186/1471-2229-9-130] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Accepted: 11/10/2009] [Indexed: 05/18/2023]
Abstract
BACKGROUND Vitamin B6 is a collective term for a group of six interconvertible compounds: pyridoxine, pyridoxal, pyridoxamine and their phosphorylated derivatives. Vitamin B6 plays essential roles as a cofactor in a range of biochemical reactions. In addition, vitamin B6 is able to quench reactive oxygen species in vitro, and exogenously applied vitamin B6 protects plant cells against cell death induced by singlet oxygen (1O2). These results raise the important question as to whether plants employ vitamin B6 as an antioxidant to protect themselves against reactive oxygen species. RESULTS The pdx1.3 mutation affects the vitamin B6 biosynthesis enzyme, pyridoxal synthase (PDX1), and leads to a reduction of the vitamin B6 concentration in Arabidopsis thaliana leaves. Although leaves of the pdx1.3 Arabidopsis mutant contained less chlorophyll than wild-type leaves, we found that vitamin B6 deficiency did not significantly impact photosynthetic performance or shoot and root growth. Chlorophyll loss was associated with an increase in the chlorophyll a/b ratio and a selective decrease in the abundance of several PSII antenna proteins (Lhcb1/2, Lhcb6). These changes were strongly dependent on light intensity, with high light amplifying the difference between pdx1.3 and the wild type. When leaf discs were exposed to exogenous 1O2, lipid peroxidation in pdx1.3 was increased relative to the wild type; this effect was not observed with superoxide or hydrogen peroxide. When leaf discs or whole plants were exposed to excess light energy, 1O2-mediated lipid peroxidation was enhanced in leaves of the pdx1.3 mutant relative to the wild type. High light also caused an increased level of 1O2 in vitamin B6-deficient leaves. Combining the pdx1.3 mutation with mutations affecting the level of 'classical' quenchers of 1O2 (zeaxanthin, tocopherols) resulted in a highly photosensitive phenotype. CONCLUSION This study demonstrates that vitamin B6 has a function in the in vivo antioxidant defense of plants. Thus, the antioxidant activity of vitamin B6 inferred from in vitro studies is confirmed in planta. Together with the finding that chloroplasts contain vitamin B6 compounds, the data show that vitamin B6 functions as a photoprotector that limits 1O2 accumulation in high light and prevents 1O2-mediated oxidative damage.
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Affiliation(s)
- Michel Havaux
- Commissariat à l'Energie Atomique (CEA), Institut de Biologie Environnementale et de Biotechnologie, Laboratoire d'Ecophysiologie Moléculaire des Plantes, 13108 Saint-Paul-lez-Durance, France
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche Biologie Végétale et Microbiologie Environnementales, 13108 Saint-Paul-lez-Durance, France
- Université Aix-Marseille, 13108 Saint-Paul-lez-Durance, France
| | - Brigitte Ksas
- Commissariat à l'Energie Atomique (CEA), Institut de Biologie Environnementale et de Biotechnologie, Laboratoire d'Ecophysiologie Moléculaire des Plantes, 13108 Saint-Paul-lez-Durance, France
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche Biologie Végétale et Microbiologie Environnementales, 13108 Saint-Paul-lez-Durance, France
- Université Aix-Marseille, 13108 Saint-Paul-lez-Durance, France
| | - Agnieszka Szewczyk
- Pharmaceutical Faculty of the Collegium Medicum, Jagiellonian University, Krakow, Poland
| | - Dominique Rumeau
- Commissariat à l'Energie Atomique (CEA), Institut de Biologie Environnementale et de Biotechnologie, Laboratoire d'Ecophysiologie Moléculaire des Plantes, 13108 Saint-Paul-lez-Durance, France
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche Biologie Végétale et Microbiologie Environnementales, 13108 Saint-Paul-lez-Durance, France
- Université Aix-Marseille, 13108 Saint-Paul-lez-Durance, France
| | - Fabrice Franck
- Laboratory of Plant Biochemistry and Photobiology, Institute of Plant Biology, University of Liège, 4000-Liège, Belgium
| | - Stefano Caffarri
- Commissariat à l'Energie Atomique (CEA), Institut de Biologie Environnementale et de Biotechnologie, Laboratoire d'Ecophysiologie Moléculaire des Plantes, 13108 Saint-Paul-lez-Durance, France
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche Biologie Végétale et Microbiologie Environnementales, 13108 Saint-Paul-lez-Durance, France
- Université Aix-Marseille, 13108 Saint-Paul-lez-Durance, France
| | - Christian Triantaphylidès
- Commissariat à l'Energie Atomique (CEA), Institut de Biologie Environnementale et de Biotechnologie, Laboratoire d'Ecophysiologie Moléculaire des Plantes, 13108 Saint-Paul-lez-Durance, France
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche Biologie Végétale et Microbiologie Environnementales, 13108 Saint-Paul-lez-Durance, France
- Université Aix-Marseille, 13108 Saint-Paul-lez-Durance, France
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Fabre N, Genty B, Rumeau D, Reiter I. Functional characterization of AtbCA5, a new chloroplastic carbonic anhydrase isoform in Arabidopsis. Comp Biochem Physiol A Mol Integr Physiol 2008. [DOI: 10.1016/j.cbpa.2008.04.505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
Besides major photosynthetic complexes of oxygenic photosynthesis, new electron carriers have been identified in thylakoid membranes of higher plant chloroplasts. These minor components, located in the stroma lamellae, include a plastidial NAD(P)H dehydrogenase (NDH) complex and a plastid terminal plastoquinone oxidase (PTOX). The NDH complex, by reducing plastoquinones (PQs), participates in one of the two electron transfer pathways operating around photosystem I (PSI), the other likely involving a still uncharacterized ferredoxin-plastoquinone reductase (FQR) and the newly discovered PGR5. The existence of a complex network of mechanisms regulating expression and activity of the NDH complex, and the presence of higher amounts of NDH complex and PTOX in response to environmental stress conditions the phenotype of mutants, indicate that these components likely play a role in the acclimation of photosynthesis to changing environmental conditions. Based on recently published data, we propose that the NDH-dependent cyclic pathway around PSI participates to the ATP supply in conditions of high ATP demand (such as high temperature or water limitation) and together with PTOX regulates cyclic electron transfer activity by tuning the redox state of intersystem electron carriers. In response to severe stress conditions, PTOX associated to the NDH and/or the PGR5 pathway may also limit electron pressure on PSI acceptor and prevent PSI photoinhibition.
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Affiliation(s)
- Dominique Rumeau
- Laboratoire d'Ecophysiologie Moléculaire des Plantes, CEA Cadarache, DSV, IBEB, SBVME, UMR 6191 CNRS/CEA/Université Aix-Marseilles, Saint Paul lez Durance F-13108, France
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14
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Fabre N, Reiter IM, Becuwe-Linka N, Genty B, Rumeau D. Characterization and expression analysis of genes encoding alpha and beta carbonic anhydrases in Arabidopsis. Plant Cell Environ 2007; 30:617-29. [PMID: 17407539 DOI: 10.1111/j.1365-3040.2007.01651.x] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Carbonic anhydrases (CAs) are Zn-containing metalloenzymes that catalyse the reversible hydration of CO(2). We investigated the alphaCA and betaCA families in Arabidopsis, which contain eight alphaCA (At alphaCA1-8) and six betaCA genes (At betaCA1-6). Analyses of expressed sequence tags (ESTs) from The Arabidopsis Information Resource (TAIR) database indicate that all the betaCA encoding sequences, but only three of the At alphaCA, are expressed. Using semi-quantitative PCR experiments, functional CA genes were more strongly expressed in green tissue, but strong expression was also found in roots for betaCA3, betaCA6 and alphaCA2. Two alphaCA genes were shown to respond to the CO(2) environment, while the others were unresponsive. Using the green fluorescent reporter protein gene fused with cDNA sequences coding for betaCAs, we provided evidence that betaCAs were targeted to specific subcellular compartments: betaCA1 and betaCA5 were targeted to the chloroplast, betaCA2 and betaCA3 to the cytosol, betaCA4 to the plasma membrane and betaCA6 to the mitochondria. The targeting and the pattern of gene expression suggest that CA isoforms play specific roles in subcellular compartments, tissues and organs. The data indicate that other CA isoforms than the well-characterized betaCA1 may contribute to the CO(2) transfer in the cell to the catalytic site of ribulose 1.5-bisphosphate carboxylase/oxygenase (Rubisco).
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Affiliation(s)
- Nicolas Fabre
- CEA/Cadarache, DSV, DEVM, Laboratoire d'Ecophysiologie Moléculaire des Plantes, UMR 6191 CNRS-CEA-Université de la Méditerranée, 13108 Saint-Paul-lez-Durance, Cedex, France
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15
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Rey P, Bécuwe N, Barrault MB, Rumeau D, Havaux M, Biteau B, Toledano MB. The Arabidopsis thaliana sulfiredoxin is a plastidic cysteine-sulfinic acid reductase involved in the photooxidative stress response. Plant J 2007; 49:505-14. [PMID: 17217469 DOI: 10.1111/j.1365-313x.2006.02969.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The 2-cysteine peroxiredoxins (2-Cys-Prxs) are antioxidants that reduce peroxides through a thiol-based mechanism. During catalysis, these ubiquitous enzymes are occasionally inactivated by the substrate-dependent oxidation of the catalytic cysteine to the sulfinic acid (-SO2H) form, and are reactivated by reduction by sulfiredoxin (Srx), an enzyme recently identified in yeast and in mammal cells. In plants, 2-Cys-Prxs constitute the most abundant Prxs and are located in chloroplasts. Here we have characterized the unique Srx gene in Arabidopsis thaliana (AtSrx) from a functional point of view, and analyzed the phenotype of two AtSrx knockout (AtSrx-) mutant lines. AtSrx is a chloroplastic enzyme displaying sulfinic acid reductase activity, as shown by the ability of the recombinant AtSrx to reduce the overoxidized 2-Cys-Prx form in vitro, and by the accumulation of the overoxidized Prx in mutant lines lacking Srx in vivo. Furthermore, AtSrx mutants exhibit an increased tolerance to photooxidative stress generated by high light combined with low temperature. These data establish that, as in yeast and in mammals, plant 2-Cys-Prxs are subject to substrate-mediated inactivation reversed by Srx, and suggest that the 2-Cys-Prx redox status and sulfiredoxin are parts of a signaling mechanism participating in plant responses to oxidative stress.
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Affiliation(s)
- Pascal Rey
- CEA, DSV, DEVM, LEMP, Laboratoire d'Ecophysiologie Moléculaire des Plantes, UMR 6191 CNRS-CEA-Université de la Méditerranée, 13108 Saint-Paul-lez-Durance, Cedex, France.
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16
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Havaux M, Rumeau D, Ducruet JM. Probing the FQR and NDH activities involved in cyclic electron transport around Photosystem I by the 'afterglow' luminescence. Biochim Biophys Acta 2005; 1709:203-13. [PMID: 16137641 DOI: 10.1016/j.bbabio.2005.07.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2005] [Revised: 06/16/2005] [Accepted: 07/06/2005] [Indexed: 11/28/2022]
Abstract
Far-red illumination of plant leaves for a few seconds induces a delayed luminescence rise, or afterglow, that can be measured with the thermoluminescence technique as a sharp band peaking at around 40-45 degrees C. The afterglow band is attributable to a heat-induced electron flow from the stroma to the plastoquinone pool and the PSII centers. Using various Arabidopsis and tobacco mutants, we show here that the electron fluxes reflected by the afterglow luminescence follow the pathways of cyclic electron transport around PSI. In tobacco, the afterglow signal relied mainly on the ferredoxin-quinone oxidoreductase (FQR) activity while the predominant pathway responsible for the afterglow in Arabidopsis involved the NAD(P)H dehydrogenase (NDH) complex. The peak temperature T(m) of the afterglow band varied markedly with the light conditions prevailing before the TL measurements, from around 30 degrees C to 45 degrees C in Arabidopsis. These photoinduced changes in Tm followed the same kinetics and responded to the same light stimuli as the state 1-state 2 transitions. PSII-exciting light (leading to state 2) induced a downward shift while preillumination with far-red light (inducing state 1) caused an upward shift. However, the light-induced downshift was strongly inhibited in NDH-deficient Arabidopsis mutants and the upward shift was cancelled in plants durably acclimated to high light, which can perform normal state transitions. Taken together, our results suggest that the peak temperature of the afterglow band is indicative of regulatory processes affecting electron donation to the PQ pool which could involve phosphorylation of NDH. The afterglow thermoluminescence band provides a new and simple tool to investigate the cyclic electron transfer pathways and to study their regulation in vivo.
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Affiliation(s)
- Michel Havaux
- CEA/Cadarache, DSV, DEVM, Laboratoire d'Ecophysiologie de la Photosynthèse, UMR 6191 CNRS-CEA-Aix Marseille II, F-13108 Saint-Paul-lez-Durance, France.
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17
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Rumeau D, Bécuwe-Linka N, Beyly A, Louwagie M, Garin J, Peltier G. New subunits NDH-M, -N, and -O, encoded by nuclear genes, are essential for plastid Ndh complex functioning in higher plants. Plant Cell 2005; 17:219-32. [PMID: 15608332 PMCID: PMC544500 DOI: 10.1105/tpc.104.028282] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2004] [Accepted: 11/09/2004] [Indexed: 05/18/2023]
Abstract
In higher plants, the Ndh complex reduces plastoquinones and is involved in cyclic electron flow around photosystem I, supplying extra-ATP for photosynthesis, particularly under environmental stress conditions. Based on plastid genome sequences, the Ndh complex would contain 11 subunits (NDH-A to -K), but homologies with bacterial complex indicate the probable existence of additional subunits. To identify missing subunits, tobacco (Nicotiana tabacum) NDH-H was His tagged at its N terminus using plastid transformation. A functional Ndh subcomplex was purified by Ni(2+) affinity chromatography and its subunit composition analyzed by mass spectrometry. Five plastid encoded subunits (NDH-A, -H, -I, -J, and -K) were identified as well as three new subunits (NDH-M, -N, and -O) homologous to cyanobacterial and higher plant proteins. Arabidopsis thaliana mutants missing one of these new subunits lack a functional Ndh complex, and NDH-M and NDH-N are not detected in a tobacco transformant lacking the Ndh complex. We discuss the involvement of these three nuclear-encoded subunits in the functional integrity of the plastidial complex.
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Affiliation(s)
- Dominique Rumeau
- Département d'Ecophysiologie Végétale et de Microbiologie, Laboratoire d'Ecophysiologie de la Photosynthèse, Centre National de la Recherche Scientifique, Université de la Méditerranée, Saint-Paul-lez-Durance, France.
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18
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Rumeau D, Bécuwe-Linka N, Beyly A, Carrier P, Cuiné S, Genty B, Medgyesy P, Horvath E, Peltier G. Increased zinc content in transplastomic tobacco plants expressing a polyhistidine-tagged Rubisco large subunit. Plant Biotechnol J 2004; 2:389-99. [PMID: 17168886 DOI: 10.1111/j.1467-7652.2004.00083.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Rubisco is a hexadecameric enzyme composed of two subunits: a small subunit (SSU) encoded by a nuclear gene (rbcS), and a large subunit (LSU) encoded by a plastid gene (rbcL). Due to its high abundance, Rubisco represents an interesting target to express peptides or small proteins as fusion products at high levels. In an attempt to modify the plant metal content, a polyhistidine sequence was fused to Rubisco, the most abundant protein of plants. Plastid transformation was used to express a polyhistidine (6x) fused to the C-terminal extremity of the tobacco LSU. Transplastomic tobacco plants were generated by cotransformation of polyethylene glycol-treated protoplasts using two vectors: one containing the 16SrDNA marker gene, conferring spectinomycin resistance, and the other the polyhistidine-tagged rbcL gene. Homoplasmic plants containing L8-(His)6S8 as a single enzyme species were obtained. These plants contained normal Rubisco amounts and activity and displayed normal photosynthetic properties and growth. Interestingly, transplastomic plants accumulated higher zinc amounts than the wild-type when grown on zinc-enriched media. The highest zinc increase observed exceeded the estimated chelating ability of the polyhistidine sequence, indicating a perturbation in intracellular zinc homeostasis. We discuss the possibility of using Rubisco to express foreign peptides as fusion products and to confer new properties to higher plants.
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Affiliation(s)
- Dominique Rumeau
- CEA Cadarache, Direction des Sciences du Vivant, Département d'Ecophysiologie Végétale et de Microbiologie, Unité Mixte de Recherche 6191 CNRS-CEA-Université de la Méditerranée, France.
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Cournac L, Josse EM, Joët T, Rumeau D, Redding K, Kuntz M, Peltier G. Flexibility in photosynthetic electron transport: a newly identified chloroplast oxidase involved in chlororespiration. Philos Trans R Soc Lond B Biol Sci 2000; 355:1447-54. [PMID: 11127998 PMCID: PMC1692870 DOI: 10.1098/rstb.2000.0705] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Besides electron transfer reactions involved in the 'Z' scheme of photosynthesis, alternative electron transfer pathways have been characterized in chloroplasts. These include cyclic electron flow around photosystem I (PS I) or a respiratory chain called chlororespiration. Recent work has supplied new information concerning the molecular nature of the electron carriers involved in the non-photochemical reduction of the plastoquinone (PQ) pool. However, until now little is known concerning the nature of the electron carriers involved in PQ oxidation. By using mass spectrometric measurement of oxygen exchange performed in the presence of 18O-enriched O2 and Chlamydomonas mutants deficient in PS I, we show that electrons can be directed to a quinol oxidase sensitive to propyl gallate but insensitive to salicyl hydroxamic acid. This oxidase has immunological and pharmacological similarities with a plastid protein involved in carotenoid biosynthesis.
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Affiliation(s)
- L Cournac
- CEA/Cadarache, DSV, DEVM, Laboratoire d'Ecophysiologie de la Photosynthèse, Saint-Paul-lez-Durance, France.
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Horváth EM, Peter SO, Joët T, Rumeau D, Cournac L, Horváth GV, Kavanagh TA, Schäfer C, Peltier G, Medgyesy P. Targeted inactivation of the plastid ndhB gene in tobacco results in an enhanced sensitivity of photosynthesis to moderate stomatal closure. Plant Physiol 2000; 123:1337-50. [PMID: 10938352 PMCID: PMC59092 DOI: 10.1104/pp.123.4.1337] [Citation(s) in RCA: 173] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/1999] [Accepted: 04/17/2000] [Indexed: 05/18/2023]
Abstract
The ndh genes encoding for the subunits of NAD(P)H dehydrogenase complex represent the largest family of plastid genes without a clearly defined function. Tobacco (Nicotiana tabacum) plastid transformants were produced in which the ndhB gene was inactivated by replacing it with a mutant version possessing translational stops in the coding region. Western-blot analysis indicated that no functional NAD(P)H dehydrogenase complex can be assembled in the plastid transformants. Chlorophyll fluorescence measurements showed that dark reduction of the plastoquinone pool by stromal reductants was impaired in ndhB-inactivated plants. Both the phenotype and photosynthetic performance of the plastid transformants was completely normal under favorable conditions. However, an enhanced growth retardation of ndhB-inactivated plants was revealed under humidity stress conditions causing a moderate decline in photosynthesis via stomatal closure. This distinctive phenotype was mimicked under normal humidity by spraying plants with abscisic acid. Measurements of CO(2) fixation demonstrated an enhanced decline in photosynthesis in the mutant plants under humidity stress, which could be restored to wild-type levels by elevating the external CO(2) concentration. These results suggest that the plastid NAD(P)H:plastoquinone oxidoreductase in tobacco performs a significant physiological role by facilitating photosynthesis at moderate CO(2) limitation.
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Affiliation(s)
- E M Horváth
- Biological Research Center, Hungarian Academy of Sciences, P.O. Box 521, H-6701 Szeged, Hungary
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Cournac L, Redding K, Ravenel J, Rumeau D, Josse EM, Kuntz M, Peltier G. Electron flow between photosystem II and oxygen in chloroplasts of photosystem I-deficient algae is mediated by a quinol oxidase involved in chlororespiration. J Biol Chem 2000; 275:17256-62. [PMID: 10748104 DOI: 10.1074/jbc.m908732199] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In Chlamydomonas reinhardtii mutants deficient in photosystem I because of inactivation of the chloroplast genes psaA or psaB, oxygen evolution from photosystem II occurs at significant rates and is coupled to a stimulation of oxygen uptake. Both activities can be simultaneously monitored by continuous mass spectrometry in the presence of (18)O(2). The light-driven O(2) exchange was shown to involve the plastoquinone pool as an electron carrier, but not cytochrome b(6)f. Photosystem II-dependent O(2) production and O(2) uptake were observed in isolated chloroplast fractions. Photosystem II-dependent oxygen exchange was insensitive to a variety of inhibitors (azide, carbon monoxide, cyanide, antimycin A, and salicylhydroxamic acid) and radical scavengers. It was, however, sensitive to propyl gallate. From inhibitors effects and electronic requirements of the O(2) uptake process, we conclude that an oxidase catalyzing oxidation of plastoquinol and reduction of oxygen to water is present in thylakoid membranes. From the sensitivity of flash-induced O(2) exchange to propyl gallate, we conclude that this oxidase is involved in chlororespiration. Clues to the identity of the protein implied in this process are given by pharmacological and immunological similarities with a protein (IMMUTANS) identified in Arabidopsis chloroplasts.
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Affiliation(s)
- L Cournac
- Commissariat à l'Energie Atomique (CEA) Cadarache, Départment d'Ecophysiologie Végétale et de Microbiologie (DEVM), Laboratoire d'Ecophysiologie de la Photosynthèse, 13108 Saint-Paul-lez-Durance, France.
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Rey P, Pruvot G, Becuwe N, Eymery F, Rumeau D, Peltier G. A novel thioredoxin-like protein located in the chloroplast is induced by water deficit in Solanum tuberosum L. plants. Plant J 1998; 13:97-107. [PMID: 9680968 DOI: 10.1046/j.1365-313x.1998.00015.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
By analysing two-dimensional patterns of chloroplastic proteins from Solanum tuberosum, the authors observed the accumulation of a 32-kDa polypeptide in the stroma of plants subjected to water deficit. N-terminus and internal peptides of the protein, named CDSP 32 for chloroplastic drought-induced stress protein, showed no obvious homology with known sequences. Using a serum raised against the protein N-terminus, a cDNA encoding CDSP 32 was cloned by screening an expression library. The deduced mature CDSP 32 protein is 243 amino acids long and displays typical features of thioredoxins in the C-terminal region (122 residues). In particular, CDSP 32 contains a CGPC motif corresponding to a thioredoxin active site and a number of amino acids conferring thioredoxin-type structure. The CDSP 32 C-terminal region was expressed as a fusion protein in Escherichia coli and was shown to possess thioredoxin activity based on reduction assay of insulin disulfide bridges. RNA blot analysis showed that CDSP 32 transcript does not accumulate upon mild water deficit conditions corresponding to leaf relative water contents (RWC) around 85%, but high levels of CDSP 32 transcripts were observed for more severe stress conditions (RWC around 70%). In vivo labelling and immunoprecipitation revealed a substantial increase in CDSP 32 synthesis upon similar stress conditions. Rewatering of wilted plants caused decreases in both transcript and protein abundances. In tomato wild-type plants and ABA-deficient mutants, a similar accumulation of a CDSP 32-related transcript was observed upon water deficit, most likely indicating no requirement for ABA in the regulation of CDSP 32 synthesis. Based on these results, it is proposed that CDSP 32 plays a role in preservation of the thiol: disulfide redox potential of chloroplastic proteins during water deficit.
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Affiliation(s)
- P Rey
- CEA/Cadarache, DSV, DEVM, Département d'Ecophysiologie Végétale et de Microbiologie, Bâtiment 161, Saint-Paul-lez-Durance, France.
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Rumeau D, Cuiné S, Fina L, Gault N, Nicole M, Peltier G. Subcellular distribution of carbonic anhydrase in Solanum tuberosum L. leaves: characterization of two compartment-specific isoforms. Planta 1996; 199:79-88. [PMID: 8680307 DOI: 10.1007/bf00196884] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The intracellular compartmentation of carbonic anhydrase (CA; EC 4.2.1.1), an enzyme that catalyses the reversible hydration of CO2 to bicarbonate, has been investigated in potato (Solanum tuberosum L.) leaves. Although enzyme activity was mainly located in chloroplasts (87% of total cellular activity), significant activity (13%) was also found in the cytosol. The corresponding CA isoforms were purified either from chloroplasts or crude leaf extracts, respectively. The cytosolic isoenzyme has a molecular mass of 255,000 and is composed of eight identical subunits with an estimated Mr of 30,000. The chloroplastic isoenzyme (Mr 220,000) is also an octamer composed of two different subunits with Mr estimated at 27,000 and 27,500, respectively. The N-terminal amino acid sequences of both chloroplastic CA subunits demonstrated that they were identical except that the Mr-27,000 subunit was three amino acids shorter than that of the Mr-27,500 subunit. Cytosolic and chloroplastic CA isoenzymes were found to be similarly inhibited by monovalent anions (Cl-, I-, N3- and NO3-) and by sulfonamides (ethoxyzolamide and acetozolamide). Both CA isoforms were found to be dependent on a reducing agent such as cysteine or dithiothreitol in order to retain the catalytic activity, but 2-mercaptoethanol was found to be a potent inhibitor. A polyclonal antibody directed against a synthetic peptide corresponding to the N-terminal amino acid sequence of the chloroplastic CA monomers also recognized the cytosolic CA isoform. This antibody was used for immunocytolocalization experiments which confirmed the intracellular compartmentation of CA: within chloroplasts, CA is restricted to the stroma and appears randomly distributed in the cytosol.
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Affiliation(s)
- D Rumeau
- CEA-CNRS, Département d'Ecophysiologie Végétale et Microbiologie, UMR-CNRS 163, Centre de Cadarache, Saint-Paul-lez Durance, France
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Abstract
Extensins comprise a family of structural cell wall hydroxyproline-rich glycoproteins in plants. Two tomato genomic clones, Tom J-10 and Tom L-4, were isolated from a tomato genomic DNA library by in situ plaque hybridization with extensin DNA probes. Tom J-10 encoded an extensin with 388 amino acid residues and a predicted molecular mass of 43 kDa. The Tom J-10 encoded extensin lacked a typical signal peptide sequence, but contained two distinct protein domains consisting of 19 tandem repeats of Ser-Pro4-Ser-Pro-Lys-Tyr-Val-Tyr-Lys at the amino terminus which were directly followed by 8 tandem repeats of the consensus sequence Ser-Pro4-Tyr3-Lys-Ser-Pro4-Ser-Pro at the carboxy terminus. RNA blot hybridization analysis with the Tom J-10 extensin probe demonstrated the presence of a 4.0 kb tomato stem mRNA which accumulated markedly in response to wounding. Tom L-4 encoded an extensin with 322 amino acid residues and a predicted molecular mass of 35 kDa. The Tom L-4 encoded extensin contained a typical signal peptide sequence at the amino terminus and was followed by at least 3 distinct domains. These domains consisted of an amino terminal domain containing several Lys-Pro and Ser-Pro4 repeat units, a central domain with repeats of the consensus sequence Ser-Pro2-5-Thr-Pro-Ser-Tyr-Glu-His-Pro-Lys-Thr-Pro, and a carboxy terminal domain containing repeats of the consensus sequence Ser-Ser-Pro4-Ser-Pro-Ser-Pro4-Thr-Tyr1-3. RNA blot hybridization analysis with the Tom L-4 extensin probe demonstrated the presence of a 2.6 kb tomato stem mRNA which accumulated in response to wounding.
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Affiliation(s)
- J Zhou
- Department of Botany, Ohio University, Athens 45701
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Showalter AM, Zhou J, Rumeau D, Worst SG, Varner JE. Tomato extensin and extensin-like cDNAs: structure and expression in response to wounding. Plant Mol Biol 1991; 16:547-65. [PMID: 1714316 DOI: 10.1007/bf00023421] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Two tomato cDNA libraries were synthesized from poly(A)+ RNAs isolated from unwounded and wounded tomato stems. These cDNA libraries were packaged in lambda gt10 and screened by in situ plaque hybridization with a tomato extensin gene clone (pTom 5.10). Several cDNA clones were identified and isolated from both libraries in this manner and subjected to restriction enzyme digestion. Southern gel blot hybridization, RNA gel blot hybridization, and DNA sequence analyses. From these analyses, the various cDNA clones were found to fall into one of five distinct classes (classes I-V). Class I clones hybridized to a 4.0 kb mRNA which accumulated markedly after wounding and encoded an extensin characterized largely by Ser-(Pro)4-Ser-Pro-Ser-(Pro)4-(Tyr)3-Lys repeats. Class II clones hybridized to a 2.6 kb mRNA which showed no accumulation following wounding and encoded an extensin containing Ser-(Pro)4-Ser-Pro-Ser-(Pro)4-Thr-(Tyr)1-3-Ser repeats. Class III clones hybridized to a 0.6 kb mRNA which greatly accumulated in response to wounding and encoded a glycine-rich protein (GRP) with (Gly)2-6-Tyr-Pro and (Gly)2-6-Arg repeats. Class IV clones contained both class I and class III DNA sequences and consequently hybridized to both the 4.0 kb and the 0.6 kb wound-accumulating mRNAs; these clones encoded a portion of a GRP sequence on one DNA strand and encoded a portion of an extensin sequence on the other DNA strand. Class V clones hybridized to a 2.3 kb mRNA which decreased following wounding and encoded a GRP sequence characterized by (Gly)2-5-Arg repeats.
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Rumeau D, Maher EA, Kelman A, Showalter AM. Extensin and Phenylalanine Ammonia-Lyase Gene Expression Altered in Potato Tubers in Response to Wounding, Hypoxia, and Erwinia carotovora Infection. Plant Physiol 1990; 93:1134-9. [PMID: 16667569 PMCID: PMC1062642 DOI: 10.1104/pp.93.3.1134] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Potato (Solanum tuberosum L.) tubers are susceptible to infection by Erwinia carotovora, causal agent of bacterial soft rot, when wounded and subjected to wet, hypoxic environments. The expression of two putative plant defense genes, extensin and phenylalanine ammonia-lyase (PAL), was examined by monitoring their respective mRNA levels and cell wall hydroxyproline levels in tuber tissues under various conditions leading to susceptibility or resistance and after inoculation with E. carotovora in order to assess the possible roles of these genes and their products in this plant-pathogen interaction. Extensin and PAL mRNA levels as well as cell wall hydroxyproline levels accumulated markedly in response to wounding and subsequent aerobic incubation. Extensin and PAL mRNA levels as well as cell wall hydroxyproline levels decreased in response to wounding and subsequent anaerobic incubation; these changes were correlated with high susceptibility of tuber tissue to E. carotovora infection. Inoculation of wound sites with E. carotovora caused some additional accumulation of the wound-regulated extensin and PAL mRNAs under certain aerobic conditions, but never under anaerobic conditions.
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Affiliation(s)
- D Rumeau
- Department of Botany, Molecular and Cellular Biology Program, Ohio University, Athens, Ohio 45701
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Mazau D, Rumeau D, Esquerre-Tugaye MT. Two different families of hydroxyproline-rich glycoproteins in melon callus: biochemical and immunochemical studies. Plant Physiol 1988; 86:540-6. [PMID: 16665943 PMCID: PMC1054520 DOI: 10.1104/pp.86.2.540] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Two different families of hydroxyproline-rich glycoproteins, HRGP(1) and HRGP(2), have been isolated from melon callus and separated by ion exchange chromatography on CM-sepharose. HRGP(1) corresponds to an arabinogalactan protein. The sugar portion of HRGP(1) accounts for 94% of the molecule and contains galactose (66%) and arabinose (34%); these residues are present as polysaccharide side chains attached to hydroxyproline. Hydroxyproline is the main amino acid residue (46%) of the protein moiety. The arabinogalactan protein nature of HRGP(1) has been checked by its ability to positively react with the beta-glucosyl Yariv antigen; the (3)H-labeled deglycosylated HRGP(1) also called HRP(1) migrates upon electrophoresis as a single band of molecular weight 76,000. HRGP(2) was fractionated by affinity chromatography on heparin-Ultrogel into three different glycoproteins, HRGP(2a,2b) and (2c). Two of these glycoproteins behave as polycations (HRGP(2b) and (2c)) and are chemically distinct from HRGP(2a). HRGP(2b) is the most abundant component and contains 41% protein and 50% sugar. Hydroxyproline, lysine, tyrosine, and arabinose are the most prominent residues of their respective moiety. The glycosylation pattern of hydroxyproline indicates that HRGP(2b) is related to and possibly a precursor of the wall HRGP; as in melon cell wall HRGP, Hyp-Ara(3) predominates, and small amounts of a putative Hyp-Ara(5) a hitherto unreported hyp-arabinoside, are recorded. The molecular weight of HRP(2b), the protein portion of HRGP(2b) is 55,000 +/- 5,000, as estimated after deglycosylation of the molecule with trifluoromethane sulfonic acid. Antibodies have been raised against HRGP(2b) and HRP(2b). Immunodiffusion shows that each antigen (HRGP(2b) or HRP(2b)) reacts with its own IgG, and cross-reacts with the heterologous IgG, thereby indicating the presence of common (unglycosylated) and specific (glycosylated and deglycosylated) epitopes. The arabinogalactan protein HRGP(1) is not recognized by either antibody and HRGP(2b) does not react with the Yariv antigen. Immunoprecipitation of (3)H-labeled HRP(1) and HRP(2b) in the presence of goat antirabbit IgG, followed by gel electrophoresis, allows to recover HRP(2b) only. Again, HRP(2b) is immunoprecipitated by the two antisera.
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Affiliation(s)
- D Mazau
- Université Paul Sabatier, Centre de Physiologie Végétale, U.A. 241, Centre National de la Recherche Scientifique, 118, route de Narbonne, 31062 Toulouse Cédex, France
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