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Hidouri S, Karmous I, Kadri O, Kharbech O, Chaoui A. Clue of zinc oxide and copper oxide nanoparticles in the remediation of cadmium toxicity in Phaseolus vulgaris L. via the modulation of antioxidant and redox systems. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:85271-85285. [PMID: 35793019 DOI: 10.1007/s11356-022-21799-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 06/28/2022] [Indexed: 06/15/2023]
Abstract
The present study represents new evidence of the successful use of metal oxide nanoparticles in the remediation of heavy metals. Zinc oxide nanoparticles (ZnO NP) and copper oxide nanoparticles (CuO NP) were assessed to alleviate cadmium (Cd) toxicity in Phaseolus vulgaris L. seedlings and plants. Monitoring physiological and metabolic parameters allowed to elucidate Cd mechanism and process whereby it exerts phytotoxic effects on bean. The response of P. vulgaris seedlings is NP dose-dependent (10 mg/L, 50 mg/L, 100 mg/L, and 200 mg/L). Similarly, applied concentrations triggered a differential response of growing plants in terms of length and biomass. Our physiological data allowed to select 100 mg/L as the most appropriate concentration to apply, in order to avoid any risk of phytotoxicity. The regulatory mechanisms by which ZnO NP and CuO NP act are for the first time compared in the embryonic axes of bean seedlings under Cd stress. Both NP were able to reduce the hypergeneration of hydrogen peroxide (H2O2). They also acted via enhancing ROS scavenging enzymatic capacity, and activity of antioxidant enzymes CAT, APX, GPOX, GPX, and GR, and inhibited the activity of ROS producing enzymes such as GOX and NOX. Another mechanistic effect of NP consisted of the modulation of redox enzymes Trx, NTR, Fd, and FNR evolved in cellular homeostasis and maintaining reduced status in cells. Taken together, ZnO NP triggered more significant metabolic regulations allowing to mitigate the oxidative damage caused by Cd.
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Affiliation(s)
- Safa Hidouri
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, Zarzouna, Tunisia
| | - Inès Karmous
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, Zarzouna, Tunisia.
- Biology and Environmental Department. Insitute of Applied Biology of Medenine (ISBAM), University of Gabes, Gabes, Tunisia.
- The Connecticut Agricultural Experiment Station (CAES), New Haven, Connecticut, USA.
| | - Oumaima Kadri
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, Zarzouna, Tunisia
| | - Oussama Kharbech
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, Zarzouna, Tunisia
| | - Abdelilah Chaoui
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, Zarzouna, Tunisia
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2
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Sakouhi L, Kharbech O, Massoud MB, Gharsallah C, Hassine SB, Munemasa S, Murata Y, Chaoui A. Calcium and ethylene glycol tetraacetic acid mitigate toxicity and alteration of gene expression associated with cadmium stress in chickpea (Cicer arietinum L.) shoots. PROTOPLASMA 2021; 258:849-861. [PMID: 33432416 DOI: 10.1007/s00709-020-01605-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 12/28/2020] [Indexed: 05/20/2023]
Abstract
In the aim to estimate the protective role of calcium (Ca) and ethylene glycol tetraacetic acid (EGTA) against cadmium (Cd)-induced damage, chickpea (Cicer arietinum L.) seeds were exposed to 200 μM Cd stress for 6 days or 3 days then subjected to co-treatment of the metal with either 100 mM CaCl2 or 100 μM EGTA for 3 additional days. The addition of Ca and EGTA improved seedling growth. This protecting effect was correlated to the alleviation of the metal-induced oxidative stress, exemplified by the reduction of hydrogen peroxide (H2O2) contents. Besides, Ca and EGTA stimulated thioredoxin (Trx) and thioredoxin reductase (NTR) activities (2.75- and 1.75-fold increase when compared to Cd-stressed, respectively) protecting, thereby, protein -SH groups from the Cd-mediated oxidation, and modulated ferredoxin (Fdx) activity to a control level. Moreover, Ca and EGTA reinstated the glutathione redox steady state, mainly via preserving a high level of glutathione reduced form (GSH). This effect coincided with the maintaining of the Cd-stimulated glutathione reductase (GR) activity and the decline of glutathione peroxidase (GPX, 43% lower than Cd-stressed shoots) activity. Ca and EGTA counteracted the inhibitory effect of Cd on the activity and gene expression of Cu/Zn-superoxide dismutase (Cu/Zn-SOD) isoenzyme and modulated the activities of catalase (CAT) and ascorbate peroxidase (APX). Overall, our results provided evidence that Ca and EGTA supplement could be a promising approach in the remediation of Cd-contaminated environment.
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Affiliation(s)
- Lamia Sakouhi
- Faculty of Sciences of Bizerte, LR18ES38 Plant Toxicology and Environmental Microbiology, University of Carthage, 7021, Bizerte, Tunisia.
| | - Oussama Kharbech
- Faculty of Sciences of Bizerte, LR18ES38 Plant Toxicology and Environmental Microbiology, University of Carthage, 7021, Bizerte, Tunisia
| | - Marouane Ben Massoud
- Faculty of Sciences of Bizerte, LR18ES38 Plant Toxicology and Environmental Microbiology, University of Carthage, 7021, Bizerte, Tunisia
- Proteomics Research Group, School of Biochemistry and Cell Biology & Environmental Research Institute, University College Cork, Lee Maltings, Prospect Row, Mardyke, Cork, Ireland
| | - Charfeddine Gharsallah
- Laboratory of Molecular Genetics, Immunology and Biotechnology, Faculty of Sciences of Tunis, University of Tunis ElManar, 2092, Tunis, Tunisia
| | - Sihem Ben Hassine
- Faculty of Sciences of Bizerte, LR18ES38 Plant Toxicology and Environmental Microbiology, University of Carthage, 7021, Bizerte, Tunisia
| | - Shintaro Munemasa
- Graduate School of Environmental and Life Science, Okayama University, Okayama, 700-8530, Japan
| | - Yoshiyuki Murata
- Graduate School of Environmental and Life Science, Okayama University, Okayama, 700-8530, Japan
| | - Abdelilah Chaoui
- Faculty of Sciences of Bizerte, LR18ES38 Plant Toxicology and Environmental Microbiology, University of Carthage, 7021, Bizerte, Tunisia
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3
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Rödiger A, Agne B, Dobritzsch D, Helm S, Müller F, Pötzsch N, Baginsky S. Chromoplast differentiation in bell pepper (Capsicum annuum) fruits. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:1431-1442. [PMID: 33258209 DOI: 10.1111/tpj.15104] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/20/2020] [Accepted: 11/24/2020] [Indexed: 05/21/2023]
Abstract
We report here a detailed analysis of the proteome adjustments that accompany chromoplast differentiation from chloroplasts during bell pepper (Capsicum annuum) fruit ripening. While the two photosystems are disassembled and their constituents degraded, the cytochrome b6 f complex, the ATPase complex, and Calvin cycle enzymes are maintained at high levels up to fully mature chromoplasts. This is also true for ferredoxin (Fd) and Fd-dependent NADP reductase, suggesting that ferredoxin retains a central role in the chromoplasts' redox metabolism. There is a significant increase in the amount of enzymes of the typical metabolism of heterotrophic plastids, such as the oxidative pentose phosphate pathway (OPPP) and amino acid and fatty acid biosynthesis. Enzymes of chlorophyll catabolism and carotenoid biosynthesis increase in abundance, supporting the pigment reorganization that goes together with chromoplast differentiation. The majority of plastid encoded proteins decline but constituents of the plastid ribosome and AccD increase in abundance. Furthermore, the amount of plastid terminal oxidase (PTOX) remains unchanged despite a significant increase in phytoene desaturase (PDS) levels, suggesting that the electrons from phytoene desaturation are consumed by another oxidase. This may be a particularity of non-climacteric fruits such as bell pepper that lack a respiratory burst at the onset of fruit ripening.
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Affiliation(s)
- Anja Rödiger
- Plant Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
- Biochemistry of Plants, Biology and Biotechnology, Ruhr-University Bochum, Bochum, Germany
| | - Birgit Agne
- Plant Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
- Biochemistry of Plants, Biology and Biotechnology, Ruhr-University Bochum, Bochum, Germany
| | - Dirk Dobritzsch
- Plant Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
| | - Stefan Helm
- Plant Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
| | - Fränze Müller
- Plant Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
- Biochemistry and Functional Proteomics, Institute of Biology II, University of Freiburg, Freiburg, Germany
| | - Nina Pötzsch
- Plant Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
| | - Sacha Baginsky
- Plant Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
- Biochemistry of Plants, Biology and Biotechnology, Ruhr-University Bochum, Bochum, Germany
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4
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Grabsztunowicz M, Rantala M, Ivanauskaite A, Blomster T, Koskela MM, Vuorinen K, Tyystjärvi E, Burow M, Overmyer K, Mähönen AP, Mulo P. Root-type ferredoxin-NADP + oxidoreductase isoforms in Arabidopsis thaliana: Expression patterns, location and stress responses. PLANT, CELL & ENVIRONMENT 2021; 44:548-558. [PMID: 33131061 DOI: 10.1111/pce.13932] [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: 09/08/2020] [Revised: 10/23/2020] [Accepted: 10/24/2020] [Indexed: 06/11/2023]
Abstract
In Arabidopsis, two leaf-type ferredoxin-NADP+ oxidoreductase (LFNR) isoforms function in photosynthetic electron flow in reduction of NADP+ , while two root-type FNR (RFNR) isoforms catalyse reduction of ferredoxin in non-photosynthetic plastids. As the key to understanding, the function of RFNRs might lie in their spatial and temporal distribution in different plant tissues and cell types, we examined expression of RFNR1 and RFNR2 genes using β-glucuronidase (GUS) reporter lines and investigated accumulation of distinct RFNR isoforms using a GFP approach and Western blotting upon various stresses. We show that while RFNR1 promoter is active in leaf veins, root tips and in the stele of roots, RFNR2 promoter activity is present in leaf tips and root stele, epidermis and cortex. RFNR1 protein accumulates as a soluble protein within the plastids of root stele cells, while RFNR2 is mainly present in the outer root layers. Ozone treatment of plants enhanced accumulation of RFNR1, whereas low temperature treatment specifically affected RFNR2 accumulation in roots. We further discuss the physiological roles of RFNR1 and RFNR2 based on characterization of rfnr1 and rfnr2 knock-out plants and show that although the function of these proteins is partly redundant, the RFNR proteins are essential for plant development and survival.
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Affiliation(s)
- Magda Grabsztunowicz
- Department of Biochemistry, Molecular Plant Biology, University of Turku, Turku, Finland
| | - Marjaana Rantala
- Department of Biochemistry, Molecular Plant Biology, University of Turku, Turku, Finland
| | - Aiste Ivanauskaite
- Department of Biochemistry, Molecular Plant Biology, University of Turku, Turku, Finland
| | - Tiina Blomster
- Organismal and Evolutionary Biology Research Program, Faculty of Biological and Environmental Sciences, and Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
| | - Minna M Koskela
- Department of Biochemistry, Molecular Plant Biology, University of Turku, Turku, Finland
| | - Katariina Vuorinen
- Organismal and Evolutionary Biology Research Program, Faculty of Biological and Environmental Sciences, and Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Esa Tyystjärvi
- Department of Biochemistry, Molecular Plant Biology, University of Turku, Turku, Finland
| | - Meike Burow
- DynaMo Center, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark
- Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Kirk Overmyer
- Organismal and Evolutionary Biology Research Program, Faculty of Biological and Environmental Sciences, and Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Ari P Mähönen
- Organismal and Evolutionary Biology Research Program, Faculty of Biological and Environmental Sciences, and Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
| | - Paula Mulo
- Department of Biochemistry, Molecular Plant Biology, University of Turku, Turku, Finland
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5
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Grabsztunowicz M, Mulo P, Baymann F, Mutoh R, Kurisu G, Sétif P, Beyer P, Krieger-Liszkay A. Electron transport pathways in isolated chromoplasts from Narcissus pseudonarcissus L. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 99:245-256. [PMID: 30888718 DOI: 10.1111/tpj.14319] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 03/05/2019] [Accepted: 03/11/2019] [Indexed: 06/09/2023]
Abstract
During daffodil flower development, chloroplasts differentiate into photosynthetically inactive chromoplasts having lost functional photosynthetic reaction centers. Chromoplasts exhibit a respiratory activity reducing oxygen to water and generating ATP. Immunoblots revealed the presence of the plastid terminal oxidase (PTOX), the NAD(P)H dehydrogenase (NDH) complex, the cytochrome b6 f complex, ATP synthase and several isoforms of ferredoxin-NADP+ oxidoreductase (FNR), and ferredoxin (Fd). Fluorescence spectroscopy allowed the detection of chlorophyll a in the cytochrome b6 f complex. Here we characterize the electron transport pathway of chromorespiration by using specific inhibitors for the NDH complex, the cytochrome b6 f complex, FNR and redox-inactive Fd in which the iron was replaced by gallium. Our data suggest an electron flow via two separate pathways, both reducing plastoquinone (PQ) and using PTOX as oxidase. The first oxidizes NADPH via FNR, Fd and cytochrome bh of the cytochrome b6 f complex, and does not result in the pumping of protons across the membrane. In the second, electron transport takes place via the NDH complex using both NADH and NADPH as electron donor. FNR and Fd are not involved in this pathway. The NDH complex is responsible for the generation of the proton gradient. We propose a model for chromorespiration that may also be relevant for the understanding of chlororespiration and for the characterization of the electron input from Fd to the cytochrome b6 f complex during cyclic electron transport in chloroplasts.
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Affiliation(s)
| | - Paula Mulo
- Molecular Plant Biology, University of Turku, 20520, Turku, Finland
| | - Frauke Baymann
- Bioénergétique et Ingénierie des Protéines, UMR 7281, CNRS - Aix-Marseille Université, 31, chemin Joseph Aiguier, 13009, Marseille, France
| | - Risa Mutoh
- Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Genji Kurisu
- Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Pierre Sétif
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette cedex, France
| | - Peter Beyer
- Faculty of Biology, University of Freiburg, 79104, Freiburg, Germany
| | - Anja Krieger-Liszkay
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette cedex, France
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6
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Ben Massoud M, Sakouhi L, Karmous I, Zhu Y, El Ferjani E, Sheehan D, Chaoui A. Protective role of exogenous phytohormones on redox status in pea seedlings under copper stress. JOURNAL OF PLANT PHYSIOLOGY 2018; 221:51-61. [PMID: 29247887 DOI: 10.1016/j.jplph.2017.11.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 11/05/2017] [Accepted: 11/09/2017] [Indexed: 05/08/2023]
Abstract
The present work aims to provide insight on the role of phytohormone application in developing efficient practical defense strategies to improve plants tolerance under heavy metal contamination. For this purpose, pea (Pisum sativum L.) seeds were germinated in an aqueous solution of 200μM CuCl2 up to the 3rd day and then continued to germinate in the presence of distilled water (stress cessation) or were subjected to following combinations: Cu+1μM IAA and Cu+1μM GA3 for 3 additional days. The results showed that copper excess induced oxidative stress in germinating seeds, which resulted in changes of the redox state of glutathione and cysteine, and proteomics revealed Cu-induced modifications of thiols (SH) and carbonyls (CO) (indicators of protein oxidation). However, application of IAA or GA3 in the germination medium after 3days of Cu exposure alleviated toxicity on seedlings, despite the persistence of Cu up to 6th day. This improving effect seems to be mediated by a cell Cu accumulation decrease and a protein reduced status recovery, since phytohormones modulate thioredoxin/ferredoxin systems in favor of protecting proteins against oxidation. In addition, an IAA and GA3 protective effect was evidenced by a cellular homeostasis amelioration resulting from the balance conservation between the regeneration and consumption processes of glutathione and cysteine reduced forms. The exogenous effectors also induced modifications of profiles of SH and CO, suggesting changes in the regulation and expression of proteins that could be involved in defense mechanism against Cu stress.
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Affiliation(s)
- Marouane Ben Massoud
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, 7021 Zarzouna, Tunisia; Proteomics Research Group, School of Biochemistry and Cell Biology & Environmental Research Institute, University College Cork, Ireland.
| | - Lamia Sakouhi
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, 7021 Zarzouna, Tunisia.
| | - Inès Karmous
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, 7021 Zarzouna, Tunisia.
| | - Yao Zhu
- Teagasc Food Research Center, Department of Food Chemistry and Technology, Ashton, Dublin 15, Ireland.
| | - Ezzedine El Ferjani
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, 7021 Zarzouna, Tunisia.
| | - David Sheehan
- Proteomics Research Group, School of Biochemistry and Cell Biology & Environmental Research Institute, University College Cork, Ireland; College of Science, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates.
| | - Abdelilah Chaoui
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, 7021 Zarzouna, Tunisia.
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7
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Mulo P, Medina M. Interaction and electron transfer between ferredoxin-NADP + oxidoreductase and its partners: structural, functional, and physiological implications. PHOTOSYNTHESIS RESEARCH 2017; 134:265-280. [PMID: 28361449 DOI: 10.1007/s11120-017-0372-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 03/20/2017] [Indexed: 05/25/2023]
Abstract
Ferredoxin-NADP+ reductase (FNR) catalyzes the last step of linear electron transfer in photosynthetic light reactions. The FAD cofactor of FNR accepts two electrons from two independent reduced ferredoxin molecules (Fd) in two sequential steps, first producing neutral semiquinone and then the fully anionic reduced, or hydroquinone, form of the enzyme (FNRhq). FNRhq transfers then both electrons in a single hydride transfer step to NADP+. We are presenting the recent progress in studies focusing on Fd:FNR interaction and subsequent electron transfer processes as well as on interaction of FNR with NADP+/H followed by hydride transfer, both from the structural and functional point of views. We also present the current knowledge about the physiological role(s) of various FNR isoforms present in the chloroplasts of higher plants and the functional impact of subchloroplastic location of FNR. Moreover, open questions and current challenges about the structure, function, and physiology of FNR are discussed.
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Affiliation(s)
- Paula Mulo
- Molecular Plant Biology, University of Turku, 20520, Turku, Finland
| | - Milagros Medina
- Department of Biochemistry and Molecular and Cellular Biology, Faculty of Sciences, and Institute of Biocomputation and Physics of Complex Systems (Joint Units: BIFI-IQFR and GBsC-CSIC), University of Zaragoza, 50009, Zaragoza, Spain.
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8
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Karmous I, Trevisan R, El Ferjani E, Chaoui A, Sheehan D. Redox biology response in germinating Phaseolus vulgaris seeds exposed to copper: Evidence for differential redox buffering in seedlings and cotyledon. PLoS One 2017; 12:e0184396. [PMID: 28981522 PMCID: PMC5628808 DOI: 10.1371/journal.pone.0184396] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 08/23/2017] [Indexed: 12/27/2022] Open
Abstract
In agriculture, heavy metal contamination of soil interferes with processes associated with plant growth, development and productivity. Here, we describe oxidative and redox changes, and deleterious injury within cotyledons and seedlings caused by exposure of germinating (Phaseolus vulgaris L. var. soisson nain hâtif) seeds to copper (Cu). Cu induced a marked delay in seedling growth, and was associated with biochemical disturbances in terms of intracellular oxidative status, redox regulation and energy metabolism. In response to these alterations, modulation of activities of antioxidant proteins (thioredoxin and glutathione reductase, peroxiredoxin) occurred, thus preventing oxidative damage. In addition, oxidative modification of proteins was detected in both cotyledons and seedlings by one- and two-dimensional electrophoresis. These modified proteins may play roles in redox buffering. The changes in activities of redox proteins underline their fundamental roles in controlling redox homeostasis. However, observed differential redox responses in cotyledon and seedling tissues showed a major capacity of the seedlings' redox systems to protect the reduced status of protein thiols, thus suggesting quantitatively greater antioxidant protection of proteins in seedlings compared to cotyledon. To our knowledge, this is the first comprehensive redox biology investigation of the effect of Cu on seed germination.
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Affiliation(s)
- Inès Karmous
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, Zarzouna, Tunisia
| | - Rafael Trevisan
- Nicholas School of the Environment, Duke University, Durham, North Carolina, United States of America
| | - Ezzeddine El Ferjani
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, Zarzouna, Tunisia
| | - Abdelilah Chaoui
- Plant Toxicology and Molecular Biology of Microorganisms, Faculty of Sciences of Bizerta, Zarzouna, Tunisia
| | - David Sheehan
- College of Science, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
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9
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Modular electron-transport chains from eukaryotic organelles function to support nitrogenase activity. Proc Natl Acad Sci U S A 2017; 114:E2460-E2465. [PMID: 28193863 DOI: 10.1073/pnas.1620058114] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
A large number of genes are necessary for the biosynthesis and activity of the enzyme nitrogenase to carry out the process of biological nitrogen fixation (BNF), which requires large amounts of ATP and reducing power. The multiplicity of the genes involved, the oxygen sensitivity of nitrogenase, plus the demand for energy and reducing power, are thought to be major obstacles to engineering BNF into cereal crops. Genes required for nitrogen fixation can be considered as three functional modules encoding electron-transport components (ETCs), proteins required for metal cluster biosynthesis, and the "core" nitrogenase apoenzyme, respectively. Among these modules, the ETC is important for the supply of reducing power. In this work, we have used Escherichia coli as a chassis to study the compatibility between molybdenum and the iron-only nitrogenases with ETC modules from target plant organelles, including chloroplasts, root plastids, and mitochondria. We have replaced an ETC module present in diazotrophic bacteria with genes encoding ferredoxin-NADPH oxidoreductases (FNRs) and their cognate ferredoxin counterparts from plant organelles. We observe that the FNR-ferredoxin module from chloroplasts and root plastids can support the activities of both types of nitrogenase. In contrast, an analogous ETC module from mitochondria could not function in electron transfer to nitrogenase. However, this incompatibility could be overcome with hybrid modules comprising mitochondrial NADPH-dependent adrenodoxin oxidoreductase and the Anabaena ferredoxins FdxH or FdxB. We pinpoint endogenous ETCs from plant organelles as power supplies to support nitrogenase for future engineering of diazotrophy in cereal crops.
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10
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Atkinson JT, Campbell I, Bennett GN, Silberg JJ. Cellular Assays for Ferredoxins: A Strategy for Understanding Electron Flow through Protein Carriers That Link Metabolic Pathways. Biochemistry 2016; 55:7047-7064. [DOI: 10.1021/acs.biochem.6b00831] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joshua T. Atkinson
- Systems,
Synthetic, and Physical Biology Graduate Program, Rice University, MS-180, 6100 Main Street, Houston, Texas 77005, United States
| | - Ian Campbell
- Biochemistry
and Cell Biology Graduate Program, Rice University, MS-140, 6100
Main Street, Houston, Texas 77005, United States
| | - George N. Bennett
- Department
of Biosciences, Rice University, MS-140, 6100 Main Street, Houston, Texas 77005, United States
- Department
of Chemical and Biomolecular Engineering, Rice University, MS-362,
6100 Main Street, Houston, Texas 77005, United States
| | - Jonathan J. Silberg
- Department
of Biosciences, Rice University, MS-140, 6100 Main Street, Houston, Texas 77005, United States
- Department
of Bioengineering, Rice University, MS-142, 6100 Main Street, Houston, Texas 77005, United States
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11
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Fisher B, Yarmolinsky D, Abdel-Ghany S, Pilon M, Pilon-Smits EA, Sagi M, Van Hoewyk D. Superoxide generated from the glutathione-mediated reduction of selenite damages the iron-sulfur cluster of chloroplastic ferredoxin. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2016; 106:228-35. [PMID: 27182957 DOI: 10.1016/j.plaphy.2016.05.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 05/04/2016] [Accepted: 05/05/2016] [Indexed: 05/23/2023]
Abstract
Selenium assimilation in plants is facilitated by several enzymes that participate in the transport and assimilation of sulfate. Manipulation of genes that function in sulfur metabolism dramatically affects selenium toxicity and accumulation. However, it has been proposed that selenite is not reduced by sulfite reductase. Instead, selenite can be non-enzymatically reduced by glutathione, generating selenodiglutathione and superoxide. The damaging effects of superoxide on iron-sulfur clusters in cytosolic and mitochondrial proteins are well known. However, it is unknown if superoxide damages chloroplastic iron-sulfur proteins. The goals of this study were twofold: to determine whether decreased activity of sulfite reductase impacts selenium tolerance in Arabidopsis, and to determine if superoxide generated from the glutathione-mediated reduction of selenite damages the iron-sulfur cluster of ferredoxin. Our data demonstrate that knockdown of sulfite reductase in Arabidopsis does not affect selenite tolerance or selenium accumulation. Additionally, we provide in vitro evidence that the non-enzymatic reduction of selenite damages the iron-sulfur cluster of ferredoxin, a plastidial protein that is an essential component of the photosynthetic light reactions. Damage to ferredoxin's iron-sulfur cluster was associated with formation of apo-ferredoxin and impaired activity. We conclude that if superoxide damages iron-sulfur clusters of ferredoxin in planta, then it might contribute to photosynthetic impairment often associated with abiotic stress, including toxic levels of selenium.
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Affiliation(s)
- Brian Fisher
- Coastal Carolina University, Biology Department, Conway, SC, 29526, USA.
| | - Dmitry Yarmolinsky
- Ben-Gurion University, Blaustein Institutes for Desert Research, Beer Sheva, Israel.
| | - Salah Abdel-Ghany
- Colorado State University, Biology Department, Fort Collins, CO, 80523, USA.
| | - Marinus Pilon
- Colorado State University, Biology Department, Fort Collins, CO, 80523, USA.
| | | | - Moshe Sagi
- Ben-Gurion University, Blaustein Institutes for Desert Research, Beer Sheva, Israel.
| | - Doug Van Hoewyk
- Coastal Carolina University, Biology Department, Conway, SC, 29526, USA.
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Xie J, Tian J, Du Q, Chen J, Li Y, Yang X, Li B, Zhang D. Association genetics and transcriptome analysis reveal a gibberellin-responsive pathway involved in regulating photosynthesis. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:3325-38. [PMID: 27091876 DOI: 10.1093/jxb/erw151] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Gibberellins (GAs) regulate a wide range of important processes in plant growth and development, including photosynthesis. However, the mechanism by which GAs regulate photosynthesis remains to be understood. Here, we used multi-gene association to investigate the effect of genes in the GA-responsive pathway, as constructed by RNA sequencing, on photosynthesis, growth, and wood property traits, in a population of 435 Populus tomentosa By analyzing changes in the transcriptome following GA treatment, we identified many key photosynthetic genes, in agreement with the observed increase in measurements of photosynthesis. Regulatory motif enrichment analysis revealed that 37 differentially expressed genes related to photosynthesis shared two essential GA-related cis-regulatory elements, the GA response element and the pyrimidine box. Thus, we constructed a GA-responsive pathway consisting of 47 genes involved in regulating photosynthesis, including GID1, RGA, GID2, MYBGa, and 37 photosynthetic differentially expressed genes. Single nucleotide polymorphism (SNP)-based association analysis showed that 142 SNPs, representing 40 candidate genes in this pathway, were significantly associated with photosynthesis, growth, and wood property traits. Epistasis analysis uncovered interactions between 310 SNP-SNP pairs from 37 genes in this pathway, revealing possible genetic interactions. Moreover, a structural gene-gene matrix based on a time-course of transcript abundances provided a better understanding of the multi-gene pathway affecting photosynthesis. The results imply a functional role for these genes in mediating photosynthesis, growth, and wood properties, demonstrating the potential of combining transcriptome-based regulatory pathway construction and genetic association approaches to detect the complex genetic networks underlying quantitative traits.
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Affiliation(s)
- Jianbo Xie
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
| | - Jiaxing Tian
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
| | - Qingzhang Du
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
| | - Jinhui Chen
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
| | - Ying Li
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
| | - Xiaohui Yang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
| | - Bailian Li
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Department of Forestry, North Carolina State University, Raleigh, NC 27695-8203, USA
| | - Deqiang Zhang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
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13
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Molecular evolution of nitrogen assimilatory enzymes in marine prasinophytes. J Mol Evol 2014; 80:65-80. [PMID: 25504421 DOI: 10.1007/s00239-014-9659-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 11/22/2014] [Indexed: 01/11/2023]
Abstract
Nitrogen assimilation is a highly regulated process requiring metabolic coordination of enzymes and pathways in the cytosol, chloroplast, and mitochondria. Previous studies of prasinophyte genomes revealed that genes encoding nitrate and ammonium transporters have a complex evolutionary history involving both vertical and horizontal transmission. Here we examine the evolutionary history of well-conserved nitrogen-assimilating enzymes to determine if a similar complex history is observed. Phylogenetic analyses suggest that genes encoding glutamine synthetase (GS) III in the prasinophytes evolved by horizontal gene transfer from a member of the heterokonts. In contrast, genes encoding GSIIE, a canonical vascular plant and green algal enzyme, were found in the Micromonas genomes but have been lost from Ostreococcus. Phylogenetic analyses placed the Micromonas GSIIs in a larger chlorophyte/vascular plant clade; a similar topology was observed for ferredoxin-dependent nitrite reductase (Fd-NiR), indicating the genes encoding GSII and Fd-NiR in these prasinophytes evolved via vertical transmission. Our results show that genes encoding the nitrogen-assimilating enzymes in Micromonas and Ostreococcus have been differentially lost and as well as recruited from different evolutionary lineages, suggesting that the regulation of nitrogen assimilation in prasinophytes will differ from other green algae.
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Ger MJ, Louh GY, Lin YH, Feng TY, Huang HE. Ectopically expressed sweet pepper ferredoxin PFLP enhances disease resistance to Pectobacterium carotovorum subsp. carotovorum affected by harpin and protease-mediated hypersensitive response in Arabidopsis. MOLECULAR PLANT PATHOLOGY 2014; 15:892-906. [PMID: 24796566 PMCID: PMC6638834 DOI: 10.1111/mpp.12150] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Plant ferredoxin-like protein (PFLP) is a photosynthesis-type ferredoxin (Fd) found in sweet pepper. It contains an iron-sulphur cluster that receives and delivers electrons between enzymes involved in many fundamental metabolic processes. It has been demonstrated that transgenic plants overexpressing PFLP show a high resistance to many bacterial pathogens, although the mechanism remains unclear. In this investigation, the PFLP gene was transferred into Arabidopsis and its defective derivatives, such as npr1 (nonexpresser of pathogenesis-related gene 1) and eds1 (enhanced disease susceptibility 1) mutants and NAHG-transgenic plants. These transgenic plants were then infected with the soft-rot bacterial pathogen Pectobacterium carotovorum subsp. carotovorum (Erwinia carotovora ssp. carotovora, ECC) to investigate the mechanism behind PFLP-mediated resistance. The results revealed that, instead of showing soft-rot symptoms, ECC activated hypersensitive response (HR)-associated events, such as the accumulation of hydrogen peroxide (H2 O2 ), electrical conductivity leakage and expression of the HR marker genes (ATHSR2 and ATHSR3) in PFLP-transgenic Arabidopsis. This PFLP-mediated resistance could be abolished by inhibitors, such as diphenylene iodonium (DPI), 1-l-trans-epoxysuccinyl-leucylamido-(4-guanidino)-butane (E64) and benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk), but not by myriocin and fumonisin. The PFLP-transgenic plants were resistant to ECC, but not to its harpin mutant strain ECCAC5082. In the npr1 mutant and NAHG-transgenic Arabidopsis, but not in the eds1 mutant, overexpression of the PFLP gene increased resistance to ECC. Based on these results, we suggest that transgenic Arabidopsis contains high levels of ectopic PFLP; this may lead to the recognition of the harpin and to the activation of the HR and other resistance mechanisms, and is dependent on the protease-mediated pathway.
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Affiliation(s)
- Mang-Jye Ger
- Department of Life Science, National University of Kaohsiung, Kaohsiung, 811, Taiwan
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15
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Hanke G, Mulo P. Plant type ferredoxins and ferredoxin-dependent metabolism. PLANT, CELL & ENVIRONMENT 2013; 36:1071-1084. [PMID: 23190083 DOI: 10.1111/pce.12046] [Citation(s) in RCA: 176] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 11/19/2012] [Accepted: 11/20/2012] [Indexed: 05/24/2023]
Abstract
Ferredoxin (Fd) is a small [2Fe-2S] cluster-containing protein found in all organisms performing oxygenic photosynthesis. Fd is the first soluble acceptor of electrons on the stromal side of the chloroplast electron transport chain, and as such is pivotal to determining the distribution of these electrons to different metabolic reactions. In chloroplasts, the principle sink for electrons is in the production of NADPH, which is mostly consumed during the assimilation of CO2 . In addition to this primary function in photosynthesis, Fds are also involved in a number of other essential metabolic reactions, including biosynthesis of chlorophyll, phytochrome and fatty acids, several steps in the assimilation of sulphur and nitrogen, as well as redox signalling and maintenance of redox balance via the thioredoxin system and Halliwell-Asada cycle. This makes Fds crucial determinants of the electron transfer between the thylakoid membrane and a variety of soluble enzymes dependent on these electrons. In this article, we will first describe the current knowledge on the structure and function of the various Fd isoforms present in chloroplasts of higher plants and then discuss the processes involved in oxidation of Fd, introducing the corresponding enzymes and discussing what is known about their relative interaction with Fd.
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Affiliation(s)
- Guy Hanke
- Plant Physiology, Faculty of Biology and Chemistry, University of Osnabrück, DE-49076, Osnabrück, Germany
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16
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Benz JP, Lintala M, Soll J, Mulo P, Bölter B. A new concept for ferredoxin-NADP(H) oxidoreductase binding to plant thylakoids. TRENDS IN PLANT SCIENCE 2010; 15:608-13. [PMID: 20851663 DOI: 10.1016/j.tplants.2010.08.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2010] [Revised: 08/18/2010] [Accepted: 08/23/2010] [Indexed: 05/25/2023]
Abstract
During the evolution of photosynthesis, regulatory circuits were established that allow the precise coupling of light-driven electron transfer chains with downstream processes such as carbon fixation. The ferredoxin (Fd):ferredoxin-NADP(+) oxidoreductase (FNR) couple is an important mediator for these processes because it provides the transition from exclusively membrane-bound light reactions to the mostly stromal metabolic pathways. Recent progress has allowed us to revisit how FNR is bound to thylakoids and to revaluate the current view that only membrane-bound FNR is active in photosynthetic reactions. We argue that the vast majority of thylakoid-bound FNR of higher plants is not necessary for photosynthesis. We furthermore propose that the correct distribution of FNR between stroma and thylakoids is used to efficiently regulate Fd-dependent electron partitioning in the chloroplast.
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Affiliation(s)
- J Philipp Benz
- Munich Center for Integrated Protein Science CiPSM, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, D-81377 Munich, Germany
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17
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Chloroplast-targeted ferredoxin-NADP(+) oxidoreductase (FNR): structure, function and location. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1807:927-34. [PMID: 20934402 DOI: 10.1016/j.bbabio.2010.10.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Revised: 10/01/2010] [Accepted: 10/02/2010] [Indexed: 11/20/2022]
Abstract
Ferredoxin-NADP(+) oxidoreductase (FNR) is a ubiquitous flavin adenine dinucleotide (FAD)-binding enzyme encoded by a small nuclear gene family in higher plants. The chloroplast targeted FNR isoforms are known to be responsible for the final step of linear electron flow transferring electrons from ferredoxin to NADP(+), while the putative role of FNR in cyclic electron transfer has been under discussion for decades. FNR has been found from three distinct chloroplast compartments (i) at the thylakoid membrane, (ii) in the soluble stroma, and (iii) at chloroplast inner envelope. Recent in vivo studies have indicated that besides the membrane-bound FNR, also the soluble FNR is photosynthetically active. Two chloroplast proteins, Tic62 and TROL, were recently identified and shown to form high molecular weight protein complexes with FNR at the thylakoid membrane, and thus seem to act as the long-sought molecular anchors of FNR to the thylakoid membrane. Tic62-FNR complexes are not directly involved in photosynthetic reactions, but Tic62 protects FNR from inactivation during the dark periods. TROL-FNR complexes, however, have an impact on the photosynthetic performance of the plants. This article is part of a Special Issue entitled: Regulation of Electron Transport in Chloroplasts.
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18
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Bilgin DD, Zavala JA, Zhu J, Clough SJ, Ort DR, DeLucia EH. Biotic stress globally downregulates photosynthesis genes. PLANT, CELL & ENVIRONMENT 2010; 33:1597-613. [PMID: 20444224 DOI: 10.1111/j.1365-3040.2010.02167.x] [Citation(s) in RCA: 323] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
To determine if damage to foliage by biotic agents, including arthropods, fungi, bacteria and viral pathogens, universally downregulates the expression of genes involved in photosynthesis, we compared transcriptome data from microarray experiments after twenty two different forms of biotic damage on eight different plant species. Transcript levels of photosynthesis light reaction, carbon reduction cycle and pigment synthesis genes decreased regardless of the type of biotic attack. The corresponding upregulation of genes coding for the synthesis of jasmonic acid and those involved in the responses to salicylic acid and ethylene suggest that the downregulation of photosynthesis-related genes was part of a defence response. Analysis of the sub-cellular targeting of co-expressed gene clusters revealed that the transcript levels of 84% of the genes that carry a chloroplast targeting peptide sequence decreased. The majority of these downregulated genes shared common regulatory elements, such as G-box (CACGTG), T-box (ACTTTG) and SORLIP (GCCAC) motifs. Strong convergence in the response of transcription suggests that the universal downregulation of photosynthesis-related gene expression is an adaptive response to biotic attack. We hypothesize that slow turnover of many photosynthetic proteins allows plants to invest resources in immediate defence needs without debilitating near term losses in photosynthetic capacity.
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Affiliation(s)
- Damla D Bilgin
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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19
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Xu Y, Gianfagna T, Huang B. Proteomic changes associated with expression of a gene (ipt) controlling cytokinin synthesis for improving heat tolerance in a perennial grass species. JOURNAL OF EXPERIMENTAL BOTANY 2010; 61:3273-89. [PMID: 20547565 PMCID: PMC2905195 DOI: 10.1093/jxb/erq149] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 04/25/2010] [Accepted: 05/10/2010] [Indexed: 05/23/2023]
Abstract
Cytokinins (CKs) are known to regulate leaf senescence and affect heat tolerance, but mechanisms underlying CK regulation of heat tolerance are not well understood. A comprehensive proteomic study was conducted to identify proteins altered by the expression of the adenine isopentenyl transferase (ipt) gene controlling CK synthesis and associated with heat tolerance in transgenic plants for a C(3) perennial grass species, Agrostis stolonifera. Transgenic plants with two different inducible promoters (SAG12 and HSP18) and a null transformant (NT) containing the vector without ipt were exposed to 20 degrees C (control) or 35 degrees C (heat stress) in growth chambers. Two-dimensional electrophoresis and mass spectrometry analysis were performed to identify protein changes in leaves and roots in response to ipt expression under heat stress. Transformation with ipt resulted in protein changes in leaves and roots involved in multiple functions, particularly in energy metabolism, protein destination and storage, and stress defence. The abundance levels of six leaf proteins (enolase, oxygen-evolving enhancer protein 2, putative oxygen-evolving complex, Rubisco small subunit, Hsp90, and glycolate oxidase) and nine root proteins (Fd-GOGAT, nucleotide-sugar dehydratase, NAD-dependent isocitrate dehydrogenase, ferredoxin-NADP reductase precursor, putative heterogeneous nuclear ribonucleoprotein A2, ascorbate peroxidase, dDTP-glucose 4-6-dehydratases-like protein, and two unknown proteins) were maintained or increased in at least one ipt transgenic line under heat stress. The diversity of proteins altered in transgenic plants in response to heat stress suggests a regulatory role for CKs in various metabolic pathways associated with heat tolerance in C(3) perennial grass species.
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Affiliation(s)
| | | | - Bingru Huang
- To whom correspondence should be addressed. E-mail:
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20
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Xu C, Sibicky T, Huang B. Protein profile analysis of salt-responsive proteins in leaves and roots in two cultivars of creeping bentgrass differing in salinity tolerance. PLANT CELL REPORTS 2010; 29:595-615. [PMID: 20361191 DOI: 10.1007/s00299-010-0847-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Revised: 02/25/2010] [Accepted: 03/16/2010] [Indexed: 05/21/2023]
Abstract
Knowledge of stress-responsive proteins is critical for further understanding the molecular mechanisms of stress tolerance. The objectives of this study were to establish a proteomic map for a perennial grass species, creeping bentgrass (A. stolonifera L.), and to identify differentially expressed, salt-responsive proteins in two cultivars differing in salinity tolerance. Plants of two cultivars ('Penncross' and 'Penn-A4') were irrigated daily with water (control) or NaCl solution to induce salinity stress in a growth chamber. Salinity stress was obtained by adding NaCl solution of 2, 4, 6, and 8 dS m(-1) in the soil daily for 2-day intervals at each concentration, and then by watering soil with 10 dS m(-1) solution daily for 28 days. For proteomic map, using two-dimensional electrophoresis (2-DE), approximately 420 and 300 protein spots were detected in leaves and roots, respectively. A total of 148 leaf protein spots and 40 root protein spots were excised from the 2-DE gels and subjected to mass spectrometry analysis. In total, 106 leaf protein spots and 24 root protein spots were successfully identified. Leaves had more salt-responsive proteins than roots in both cultivars. The superior salt tolerance in 'Penn-A4', indicated by shoot extension rate, relative water content, and cell membrane stability during the 28-day salinity stress could be mainly associated with its higher level of vacuolar H(+)-ATPase in roots and UDP-sulfoquinovose synthase, methionine synthase, and glucan exohydrolase in leaves, as well as increased accumulation of catalase and glutathione S-transferase in leaves. Our results suggest that salinity tolerance in creeping bentgrass could be in part controlled by an alteration of ion transport through vacuolar H(+)-ATPase in roots, maintenance of the functionality and integrity of thylakoid membranes, sustained polyamine biosynthesis, and by the activation of cell wall loosening proteins and antioxidant defense mechanisms.
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Affiliation(s)
- Chenping Xu
- Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ, 08901, USA
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21
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Korn A, Ajlani G, Lagoutte B, Gall A, Sétif P. Ferredoxin:NADP+ oxidoreductase association with phycocyanin modulates its properties. J Biol Chem 2009; 284:31789-97. [PMID: 19759024 DOI: 10.1074/jbc.m109.024638] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In photosynthetic organisms, ferredoxin:NADP(+) oxidoreductase (FNR) is known to provide NADPH for CO(2) assimilation, but it also utilizes NADPH to provide reduced ferredoxin. The cyanobacterium Synechocystis sp. strain PCC6803 produces two FNR isoforms, a small one (FNR(S)) similar to the one found in plant plastids and a large one (FNR(L)) that is associated with the phycobilisome, a light-harvesting complex. Here we show that a mutant lacking FNR(L) exhibits a higher NADP(+)/NADPH ratio. We also purified to homogeneity a phycobilisome subcomplex comprising FNR(L,) named FNR(L)-PC. The enzymatic activities of FNR(L)-PC were compared with those of FNR(S). During NADPH oxidation, FNR(L)-PC exhibits a 30% decrease in the Michaelis constant K(m)((NADPH)), and a 70% increase in K(m)((ferredoxin)), which is in agreement with its predicted lower activity of ferredoxin reduction. During NADP(+) reduction, the FNR(L)-PC shows a 29/43% decrease in the rate of single electron transfer from reduced ferredoxin in the presence/absence of NADP(+). The increase in K(m)((ferredoxin)) and the rate decrease of single reduction are attributed to steric hindrance by the phycocyanin moiety of FNR(L)-PC. Both isoforms are capable of catalyzing the NADP(+) reduction under multiple turnover conditions. Furthermore, we obtained evidence that, under high ionic strength conditions, electron transfer from reduced ferredoxin is rate limiting during this process. The differences that we observe might not fully explain the in vivo properties of the Synechocystis mutants expressing only one of the isoforms. Therefore, we advocate that FNR localization and/or substrates availability are essential in vivo.
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Affiliation(s)
- Anja Korn
- Institut de Biologie et de Technologie de Saclay, Commissariat à L'Energie Atomique, CNRS, F-91191 Gif sur Yvette, France
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Venegas-Calerón M, Zambelli A, Ruiz-López N, Youssar L, León A, Garcés R, Martínez-Force E. cDNA cloning, expression levels and gene mapping of photosynthetic and non-photosynthetic ferredoxin genes in sunflower (Helianthus annuus L.). TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2009; 118:891-901. [PMID: 19130032 DOI: 10.1007/s00122-008-0947-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Accepted: 12/04/2008] [Indexed: 05/27/2023]
Abstract
Fatty acid desaturation in plastids and chloroplasts depends on the electron-donor activity of ferredoxins. Using degenerate oligonucleotides designed from known photosynthetic and heterotrophic plant ferredoxin sequences, two full-length ferredoxin cDNAs were cloned from sunflower (Helianthus annuus L.) leaves and developing seeds, HaFd1 and HaFd2, homologous to photosynthetic and non-photosynthetic ferredoxins, respectively. Based on these cDNAs, the respective genomic sequences were obtained and the presence of DNA polymorphisms was investigated. Complete sequencing of the HaFd1 and HaFd2 genes in different lines indicated the presence of two haplotypes for HaFd2 and their alignment showed that sequence polymorphisms are restricted to the 5'-NTR intron. In addition, specific DNA markers for the HaFd1 and HaFd2 genes were developed that enabled the genes to be mapped. Accordingly, the HaFd1 locus maps to linkage group 10 of the public sunflower map, while the HaFd2 locus maps to linkage group 11. Both ferredoxins display different spatial-temporal patterns of expression. While HaFd2 is expressed at similar levels in all tissues tested (leaves, stem, roots, cotyledons and developing seeds), HaFd1 is more strongly expressed in green tissues than in all the other tissues tested. Both photosynthetic- and heterotrophic-ferredoxins are present in sunflower seeds and may contribute to fatty acid desaturation during oil accumulation. Nevertheless, the levels of HaFd2 expression during seed formation are distinct in lines that only varied in the HaFd2 haplotypes they expressed.
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Affiliation(s)
- M Venegas-Calerón
- Instituto de la Grasa (CSIC), Av. Padre García Tejero 4, 41012, Sevilla, Spain
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Grzyb J, Malec P, Rumak I, Garstka M, Strzałka K. Two isoforms of ferredoxin:NADP(+) oxidoreductase from wheat leaves: purification and initial biochemical characterization. PHOTOSYNTHESIS RESEARCH 2008; 96:99-112. [PMID: 18253859 DOI: 10.1007/s11120-008-9289-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Accepted: 01/17/2008] [Indexed: 05/25/2023]
Abstract
Ferredoxin:NADP(+) oxidoreductase is an enzyme associated with the stromal side of the thylakoid membrane in the chloroplast. It is involved in photosynthetic linear electron transport to produce NADPH and is supposed to play a role in cyclic electron transfer, generating a transmembrane pH gradient allowing ATP production, if photosystem II is non-functional or no NADP(+) is available for reduction. Different FNR isoforms have been described in non-photosynthetic tissues, where the enzyme catalyses the NADPH-dependent reduction of ferredoxin (Fd), necessary for some biosynthetic pathways. Here, we report the isolation and purification of two FNR isoproteins from wheat leaves, called FNR-A and FNR-B. These forms of the enzyme were identified as products of two different genes, as confirmed by mass spectrometry. The molecular masses of FNR-A and FNR-B were 34.3 kDa and 35.5 kDa, respectively. The isoelectric point of both FNR-A and FNR-B was about 5, but FNR-B appeared more acidic (of about 0.2 pH unit) than FNR-A. Both isoenzymes were able to catalyse a NADPH-dependent reduction of dibromothymoquinone and the mixture of isoforms catalysed reduction of cytochrome c in the presence of Fd. For the first time, the pH- and ionic strength dependent oligomerization of FNRs is observed. No other protein was necessary for complex formation. The putative role of the two FNR isoforms in photosynthesis is discussed based on current knowledge of electron transport in chloroplasts.
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Affiliation(s)
- Joanna Grzyb
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, ul. Gronostajowa 7, 30-387 Kraków, Poland
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Huang HE, Liu CA, Lee MJ, Kuo CG, Chen HM, Ger MJ, Tsai YC, Chen YR, Lin MK, Feng TY. Resistance enhancement of transgenic tomato to bacterial pathogens by the heterologous expression of sweet pepper ferredoxin-I protein. PHYTOPATHOLOGY 2007; 97:900-906. [PMID: 18943629 DOI: 10.1094/phyto-97-8-0900] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
ABSTRACT Expression of a foreign gene to enhance plant disease resistance to bacterial pathogens is a favorable strategy. It has been demonstrated that expressing sweet pepper ferredoxin-I protein (PFLP) in transgenic plants can enhance disease resistance to bacterial pathogens that infect leaf tissue. In this study, PFLP was applied to protect tomato (Lycopersicon esculentum cv. cherry Cln1558a) from the root-infecting pathogen, Ralstonia solanacearum. Independent R. solanacearum resistant T(1) lines were selected and bred to produce homozygous T(2) generations. Selected T(2) transgenic lines 24-18-7 and 26-2-1a, which showed high expression levels of PFLP in root tissue, were resistant to disease caused by R. solanacearum. In contrast, the transgenic line 23-17-1b and nontransgenic tomato, which showed low expression levels of PFLP in root tissue, were not resistant to R. solanacearum infection. The expansion of R. solanacearum populations in stem tissue of transgenic tomato line 24-18-7 was limited compared with the nontransgenic tomato Cln1558a. Using a detached leaf assay, transgenic line 24-18-7 was also resistant to maceration caused by E. carotovora subsp. carotovora; however, resistance to E. carotovora subsp. carotovora was less apparent in transgenic lines 26-2-1a and 23-17-1b. These results demonstrate that PFLP is able to enhance disease resistance at different levels to bacterial pathogens in individual tissue of transgenic tomato.
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Huang HE, Ger MJ, Chen CY, Pandey AK, Yip MK, Chou HW, Feng TY. Disease resistance to bacterial pathogens affected by the amount of ferredoxin-I protein in plants. MOLECULAR PLANT PATHOLOGY 2007; 8:129-37. [PMID: 20507485 DOI: 10.1111/j.1364-3703.2006.00378.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
SUMMARY Ferredoxin-I (Fd-I) is a fundamental protein that is involved in several metabolic pathways. The amount of Fd-I found in plants is generally regulated by environmental stress, including biotic and abiotic events. In this study, the correlation between quantity of Fd-I and plant disease resistance was investigated. Fd-I levels were increased by inoculation with Pseudomonas syringae pv. syringae but were reduced by Erwinia carotovora ssp. carotovora. Transgenic tobacco over-expressing Fd-I with the sense sweet pepper Fd-I gene (pflp) was resistant to E. carotovora ssp. carotovora and the saprophytic bacterium P. fluorescens. By contrast, transgenic tobacco with reduced total Fd-I and the antisense pflp gene was susceptible to E. carotovora ssp. carotovora and P. fluorescens. Both of these transgenic tobaccos were resistant to P. syringae pv. syringae. By contrast, the mutated E. carotovora ssp. carotovora, with a defective harpin protein, was able to invade the sense-pflp transgenic tobacco as well as the non-transgenic tobacco. An in vitro kinase assay revealed that harpin could activate unidentified kinases to phosphorylate PFLP. These results demonstrate that Fd-I plays an important role in the disease defence mechanism.
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Affiliation(s)
- Hsiang-En Huang
- Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 115, Taiwan
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Balmer Y, Vensel WH, Cai N, Manieri W, Schürmann P, Hurkman WJ, Buchanan BB. A complete ferredoxin/thioredoxin system regulates fundamental processes in amyloplasts. Proc Natl Acad Sci U S A 2006; 103:2988-93. [PMID: 16481623 PMCID: PMC1413819 DOI: 10.1073/pnas.0511040103] [Citation(s) in RCA: 145] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
A growing number of processes throughout biology are regulated by redox via thiol-disulfide exchange. This mechanism is particularly widespread in plants, where almost 200 proteins have been linked to thioredoxin (Trx), a widely distributed small regulatory disulfide protein. The current study extends regulation by Trx to amyloplasts, organelles prevalent in heterotrophic plant tissues that, among other biosynthetic activities, catalyze the synthesis and storage of copious amounts of starch. Using proteomics and immunological methods, we identified the components of the ferredoxin/Trx system (ferredoxin, ferredoxin-Trx reductase, and Trx), originally described for chloroplasts, in amyloplasts isolated from wheat starchy endosperm. Ferredoxin is reduced not by light, as in chloroplasts, but by metabolically generated NADPH via ferredoxin-NADP reductase. However, once reduced, ferredoxin appears to act as established for chloroplasts, i.e., via ferredoxin-Trx reductase and a Trx (m-type). A proteomics approach in combination with affinity chromatography and a fluorescent thiol probe led to the identification of 42 potential Trx target proteins, 13 not previously recognized, including a major membrane transporter (Brittle-1 or ADP-glucose transporter). The proteins function in a range of processes in addition to starch metabolism: biosynthesis of lipids, amino acids, and nucleotides; protein folding; and several miscellaneous reactions. The results suggest a mechanism whereby light is initially recognized as a thiol signal in chloroplasts, then as a sugar during transit to the sink, where it is converted again to a thiol signal. In this way, amyloplast reactions in the grain can be coordinated with photosynthesis taking place in leaves.
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Affiliation(s)
- Yves Balmer
- *Department of Plant and Biology, University of California, 111 Koshland Hall, Berkeley, CA 94720
| | - William H. Vensel
- Western Regional Research Center, U.S. Department of Agriculture Agricultural Research Service, Albany, CA 94710; and
| | - Nick Cai
- *Department of Plant and Biology, University of California, 111 Koshland Hall, Berkeley, CA 94720
| | - Wanda Manieri
- Laboratoire de Biochimie Végétale, Université de Neuchātel, 2007 Neuchātel, Switzerland
| | - Peter Schürmann
- Laboratoire de Biochimie Végétale, Université de Neuchātel, 2007 Neuchātel, Switzerland
| | - William J. Hurkman
- Western Regional Research Center, U.S. Department of Agriculture Agricultural Research Service, Albany, CA 94710; and
| | - Bob B. Buchanan
- *Department of Plant and Biology, University of California, 111 Koshland Hall, Berkeley, CA 94720
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Okutani S, Hanke GT, Satomi Y, Takao T, Kurisu G, Suzuki A, Hase T. Three maize leaf ferredoxin:NADPH oxidoreductases vary in subchloroplast location, expression, and interaction with ferredoxin. PLANT PHYSIOLOGY 2005; 139:1451-9. [PMID: 16244136 PMCID: PMC1283780 DOI: 10.1104/pp.105.070813] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In higher plants, ferredoxin (Fd):NADPH oxidoreductase (FNR) catalyzes reduction of NADP+ in the final step of linear photosynthetic electron transport and is also implicated in cyclic electron flow. We have identified three leaf FNR isoenzymes (LFNR1, LFNR2, and LFNR3) in maize (Zea mays) chloroplasts at approximately equivalent concentrations. Fractionation of chloroplasts showed that, while LFNR3 is an exclusively soluble enzyme, LFNR1 is only found at the thylakoid membrane and LFNR2 has a dual location. LFNR1 and LFNR2 were found to associate with the cytochrome b6f complex following its partial purification. We cloned LFNR3 and produced all three isoenzymes as stable, soluble proteins. Measurement of Fd reduction ability showed no significant differences between these recombinant enzymes. Column chromatography revealed variation between the interaction mechanisms of LFNR1 and LFNR2 with Fd, as detected by differential dependence on specific intermolecular salt bridges and variable sensitivity of interactions to changes in pH. A comparison of LFNR transcripts in leaves of plants grown on variable nitrogen regimes revealed that LFNR1 and LFNR2 transcripts are relatively more abundant under conditions of high demand for NADPH. These results are discussed in terms of the functional differentiation of maize LFNR isoenzymes.
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Affiliation(s)
- Satoshi Okutani
- Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan
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Hanke GT, Kurisu G, Kusunoki M, Hase T. Fd : FNR Electron Transfer Complexes: Evolutionary Refinement of Structural Interactions. PHOTOSYNTHESIS RESEARCH 2004; 81:317-27. [PMID: 16034535 DOI: 10.1023/b:pres.0000036885.01534.b8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
During the evolution of higher-plant root and leaf-type-specific Fd : FNR complexes from an original cyanobacterial type progenitor, rearrangement of molecular interaction has altered the relative orientation of prosthetic groups and there have been changes in complex induced conformational change. Selection has presumably worked on mutation of residues responsible for interaction between the two proteins, favoring optimized electron flow in a specific direction, and efficient dissociation following specific oxidation of leaf Fd and reduction of root Fd. Major changes appear to be: loss in both leaf and root complexes of a cyanobacterial mechanism that ensures Fd dissociation from the complex following change in Fd redox state, development of a structural rearrangement of Fd on binding to leaf FNR that results in a negative shift in Fd redox potential favorable to photosynthetic electron flow, creation of a vacant space in the root Fd:FNR complex that may allow access to the redox centers of other enzymes to ensure efficient channeling of heterotrophic reductant into bioassimilation. Further structural analysis is essential to establish how root type FNR distinguishes between Fd isoforms, and discover how residues not directly involved in intermolecular interactions may affect complex formation.
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Affiliation(s)
- Guy T Hanke
- Division of Enzymology, Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan,
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30
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Holtgrefe S, Bader KP, Horton P, Scheibe R, von Schaewen A, Backhausen JE. Decreased content of leaf ferredoxin changes electron distribution and limits photosynthesis in transgenic potato plants. PLANT PHYSIOLOGY 2003; 133:1768-78. [PMID: 14645726 PMCID: PMC300731 DOI: 10.1104/pp.103.026013] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2003] [Revised: 05/13/2003] [Accepted: 08/14/2003] [Indexed: 05/18/2023]
Abstract
A complete ferredoxin (Fd) cDNA clone was isolated from potato (Solanum tuberosum L. cv Desiree) leaves. By molecular and immunoblot analysis, the gene was identified as the leaf-specific Fd isoform I. Transgenic potato plants were constructed by introducing the homologous potato fed 1 cDNA clone as an antisense construct under the control of the constitutive cauliflower mosaic virus 35S promoter. Stable antisense lines with Fd contents between 40% and 80% of the wild-type level were selected by northern- and western-blot analysis. In short-term experiments, the distribution of electrons toward their stromal acceptors was altered in the mutant plants. Cyclic electron transport, as determined by the quantum yields of photosystems I and II, was enhanced. The CO2 assimilation rate was decreased, but depending on the remaining Fd content, some lines showed photoinhibition. The leaf protein content remained largely constant, but the antisense plants had a lower total chlorophyll content per unit leaf area and an increased chlorophyll a/b ratio. In the antisense plants, the redox state of the quinone acceptor A in photosystem II (QA) was more reduced than that of the wild-type plants under all experimental conditions. Because the plants with lower Fd amounts reacted as if they were grown under a higher light intensity, the possibility that the altered chloroplast redox state affects light acclimation is discussed.
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Affiliation(s)
- Simone Holtgrefe
- Pflanzenphysiologie, Fachbereich Biologie/Chemie, Universität Osnabrück, 9069 Osnabrück, Germany
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31
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Schultz DJ, Suh MC, Ohlrogge JB. Stearoyl-acyl carrier protein and unusual acyl-acyl carrier protein desaturase activities are differentially influenced by ferredoxin. PLANT PHYSIOLOGY 2000; 124:681-92. [PMID: 11027717 PMCID: PMC59173 DOI: 10.1104/pp.124.2.681] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2000] [Accepted: 06/20/2000] [Indexed: 05/20/2023]
Abstract
Acyl-acyl carrier protein (ACP) desaturases function to position a single double bond into an acyl-ACP substrate and are best represented by the ubiquitous Delta9 18:0-ACP desaturase. Several variant acyl-ACP desaturases have also been identified from species that produce unusual monoenoic fatty acids. All known acyl-ACP desaturase enzymes use ferredoxin as the electron-donating cofactor, and in almost all previous studies the photosynthetic form of ferredoxin rather than the non-photosynthetic form has been used to assess activity. We have examined the influence of different forms of ferredoxin on acyl-ACP desaturases. Using combinations of in vitro acyl-ACP desaturase assays and [(14)C]malonyl-coenzyme A labeling studies, we have determined that heterotrophic ferredoxin isoforms support up to 20-fold higher unusual acyl-ACP desaturase activity in coriander (Coriandrum sativum), Thunbergia alata, and garden geranium (Pelargonium x hortorum) when compared with photosynthetic ferredoxin isoforms. Heterotrophic ferredoxin also increases activity of the ubiquitous Delta9 18:0-ACP desaturase 1.5- to 3.0-fold in both seed and leaf extracts. These results suggest that ferredoxin isoforms may specifically interact with acyl-ACP desaturases to achieve optimal enzyme activity and that heterotrophic isoforms of ferredoxin may be the in vivo electron donor for this reaction.
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Affiliation(s)
- D J Schultz
- Department of Botany and Plant Pathology, Michigan State University, East Lansing, Michigan 48824, USA
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32
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Onda Y, Matsumura T, Kimata-Ariga Y, Sakakibara H, Sugiyama T, Hase T. Differential interaction of maize root ferredoxin:NADP(+) oxidoreductase with photosynthetic and non-photosynthetic ferredoxin isoproteins. PLANT PHYSIOLOGY 2000; 123:1037-45. [PMID: 10889253 PMCID: PMC59067 DOI: 10.1104/pp.123.3.1037] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/1999] [Accepted: 03/27/2000] [Indexed: 05/20/2023]
Abstract
In higher plants ferredoxin (Fd):NADP(+) oxidoreductase (FNR) and Fd are each distributed in photosynthetic and non-photosynthetic organs as distinct isoproteins. We have cloned cDNAs for leaf FNR (L-FNR I and L-FNR II) and root FNR (R-FNR) from maize (Zea mays L.), and produced recombinant L-FNR I and R-FNR to study their enzymatic functions through kinetic and Fd-binding analyses. The K(m) value obtained by assay for a diaphorase activity indicated that R-FNR had a 10-fold higher affinity for NADPH than L-FNR I. When we assayed for NADPH-cytochrome c reductase activity using maize photosynthetic Fd (Fd I) and non-photosynthetic Fd (Fd III), the R-FNR showed a marked difference in affinity between these two Fd isoproteins; the K(m) for Fd III was 3.0 microM and that for Fd I was 29 microM. Consistent with this, the dissociation constant for the R-FNR:Fd III complex was 10-fold smaller than that of the R-FNR:Fd I complex. This differential binding capacity was confirmed by an affinity chromatography of R-FNR on Fd-sepharose with stronger binding to Fd III. L-FNR I showed no such differential interaction with Fd I and Fd III. These data demonstrated that R-FNR has the ability to discriminate between these two types of Fds. We propose that the stronger interaction of R-FNR with Fd III is crucial for an efficient electron flux of NADPH-FNR-Fd cascade, thus supporting Fd-dependent metabolism in non-photosynthetic organs.
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Affiliation(s)
- Y Onda
- Division of Enzymology, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871 Japan
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33
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Yoshizaki M, Furumoto T, Hata S, Shinozaki M, Izui K. cDNA cloning and expression analysis of a non-photosynthetic ferredoxin gene in morning glory (Pharbitis nil). BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1491:273-8. [PMID: 10760590 DOI: 10.1016/s0167-4781(00)00018-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A full-length cDNA encoding a non-photosynthetic ferredoxin was isolated from apical buds of morning glory (Pharbitis nil), a short-day plant, by differential screening under flower-inducing and non-inducing conditions. Northern analysis and in situ hybridization showed that the transcript was abundant in shoot apices and root tips. The transcript level in the apical buds decreased with the flower-inducing light treatment.
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Affiliation(s)
- M Yoshizaki
- Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Sakyo-Ku, Kyoto, Japan
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34
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Yonekura-Sakakibara K, Onda Y, Ashikari T, Tanaka Y, Kusumi T, Hase T. Analysis of reductant supply systems for ferredoxin-dependent sulfite reductase in photosynthetic and nonphotosynthetic organs of maize. PLANT PHYSIOLOGY 2000; 122:887-94. [PMID: 10712553 PMCID: PMC58925 DOI: 10.1104/pp.122.3.887] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/1999] [Accepted: 12/02/1999] [Indexed: 05/20/2023]
Abstract
Sulfite reductase (SiR) catalyzes the reduction of sulfite to sulfide in chloroplasts and root plastids using ferredoxin (Fd) as an electron donor. Using purified maize (Zea mays L.) SiR and isoproteins of Fd and Fd-NADP(+) reductase (FNR), we reconstituted illuminated thylakoid membrane- and NADPH-dependent sulfite reduction systems. Fd I and L-FNR were distributed in leaves and Fd III and R-FNR in roots. The stromal concentrations of SiR and Fd I were estimated at 1.2 and 37 microM, respectively. The molar ratio of Fd III to SiR in root plastids was approximately 3:1. Photoreduced Fd I and Fd III showed a comparable ability to donate electrons to SiR. In contrast, when being reduced with NADPH via FNRs, Fd III showed a several-fold higher activity than Fd I. Fd III and R-FNR showed the highest rate of sulfite reduction among all combinations tested. NADP(+) decreased the rate of sulfite reduction in a dose-dependent manner. These results demonstrate that the participation of Fd III and high NADPH/NADP(+) ratio are crucial for non-photosynthetic sulfite reduction. In accordance with this view, a cysteine-auxotrophic Escherichia coli mutant defective for NADPH-dependent SiR was rescued by co-expression of maize SiR with Fd III but not with Fd I.
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Affiliation(s)
- K Yonekura-Sakakibara
- Institute for Fundamental Research, Suntory Ltd., Wakayamadai, Shimamoto, Mishima, Osaka, 618-8503 Japan.
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35
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Wright DP, Huppe HC, Turpin DH. In Vivo and in Vitro Studies of Glucose-6-Phosphate Dehydrogenase from Barley Root Plastids in Relation to Reductant Supply for NO2- Assimilation. PLANT PHYSIOLOGY 1997; 114:1413-1419. [PMID: 12223780 PMCID: PMC158434 DOI: 10.1104/pp.114.4.1413] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Pyridine nucleotide pools were measured in intact plastids from roots of barley (Hordeum vulgare L.) during the onset of NO2- assimilation and compared with the in vitro effect of the NADPH/NADP ratio on the activity of plastidic glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) from N-sufficient or N-starved roots. The NADPH/NADP ratio increased from 0.9 to 2.0 when 10 mM glucose-6-phosphate was supplied to intact plastids. The subsequent addition of 1 mM NaNO2 caused a rapid decline in this ratio to 1.5. In vitro, a ratio of 1.5 inactivated barley root plastid G6PDH by approximately 50%, suggesting that G6PDH could remain active during NO2- assimilation even at the high NADPH/NADP ratios that would favor a reduction of ferredoxin, the electron donor of NO2- reductase. Root plastid G6PDH was sensitive to reductive inhibition by dithiothreitol (DTT), but even at 50 mM DTT the enzyme remained more than 35% active. In root plastids from barley starved of N for 3 d, G6PDH had a substantially reduced specific activity, had a lower Km for NADP, and was less inhibited by DTT than the enzyme from N-sufficient root plastids, indicating that there was some effect of N starvation on the G6PDH activity in barley root plastids.
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Affiliation(s)
- D. P. Wright
- Department of Biology, Queen's University, Kingston, Ontario, Canada K7L 3N6
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36
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Bouvier F, d'Harlingue A, Hugueney P, Marin E, Marion-Poll A, Camara B. Xanthophyll biosynthesis. Cloning, expression, functional reconstitution, and regulation of beta-cyclohexenyl carotenoid epoxidase from pepper (Capsicum annuum). J Biol Chem 1996; 271:28861-7. [PMID: 8910532 DOI: 10.1074/jbc.271.46.28861] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Pepper (Capsicum annuum) beta-cyclohexenyl xanthophyll epoxidase cDNA was cloned and the corresponding enzyme overexpressed and purified from Escherichia coli, for investigation of its catalytic activity. The recombinant protein did not directly accept NADPH for epoxidation of cyclohexenyl carotenoids, nor did it operate according to a peroxygenase-based mechanism. Instead, the reducing power of NADPH was transferred to the epoxidase via reduced ferredoxin as shown by reconstitution of epoxidase activity in the presence of NADPH, ferredoxin oxidoreductase, and ferredoxin. Bacterial rubredoxin could be substituted for ferredoxin. The pepper epoxidase acted specifically on the beta-ring of xanthophylls such as beta-cryptoxanthin, zeaxanthin, and antheraxanthin. The proposed reaction mechanism for epoxidation involves the formation of a transient carbocation. This characteristic allows selective inhibition of the epoxidase activity by different nucleophilic diethylamine derivatives, p-dimethylaminobenzenediazonium fluoroborate and N,N-dimethyl-2-phenylaziridinium. It was also shown that the epoxidase gene was up-regulated during oxidative stress and when chloroplasts undergo differentiation into chromoplasts in pepper fruit.
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Affiliation(s)
- F Bouvier
- Institut de Biologie Moléculaire des Plantes du Centre National de la Recherche Scientifique, Université Louis Pasteur, 12 rue du Général Zimmer, 67084 Strasbourg, France.
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37
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Razquin P, Fillat MF, Schmitz S, Stricker O, Böhme H, Gómez-Moreno C, Peleato ML. Expression of ferredoxin-NADP+ reductase in heterocysts from Anabaena sp. Biochem J 1996; 316 ( Pt 1):157-60. [PMID: 8645199 PMCID: PMC1217316 DOI: 10.1042/bj3160157] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The expression of ferredoxin-NADP+ reductase (FNR) from Anabaena sp. PCC 7119 in heterocysts and vegetative cells has been quantified. Specific reductase activity in heterocysts was approximately 10 times higher than in vegetative cells, corresponding to the increased FNR protein content. This was confirmed by immunoquantification of the FNR protein from whole filaments of Anabaena sp. PCC 7120 grown in media with and without combined nitrogen. Transcription of the petH gene was markedly enhanced in the absence of combined nitrogen. This suggests that the increased RNA level is mainly responsible for the up-regulation of FNR in heterocysts. As has been observed for nif genes, iron deficiency also increased transcription of petH. Characterization of the FNR purified from isolated heterocysts showed no detectable differences from the enzyme from vegetative cells. Although nitrogen stress was a key regulatory factor, localization of the petH gene in the genomic map of Anabaena PCC 7120 showed that this gene is not physically associated with the nif cluster.
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Affiliation(s)
- P Razquin
- Departamento de Bioquímica y Biología Molecular y Cellular, Facultad de Ciencias, Universidad de Zaragoza, Spain
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Alonso JM, Chamarro J, Granell A. A non-photosynthetic ferredoxin gene is induced by ethylene in Citrus organs. PLANT MOLECULAR BIOLOGY 1995; 29:1211-1221. [PMID: 8616219 DOI: 10.1007/bf00020463] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The sequence and expression of mRNA homologous to a cDNA encoding a non-photosynthetic ferredoxin (Fd1) from Citrus fruit was investigated. The non-photosynthetic nature of this ferredoxin was deduced from: (1) amino acid sequence alignments showing better scores with non-photosynthetic than with photosynthetic ferredoxins, (2) higher expression in tissues containing plastids other than chloroplast such as petals, young fruits, roots and peel of fully coloured fruits, and (3) the absence of light-dark regulation characteristic of photosynthetic ferredoxins. In a phylogenetic tree constructed with higher-plant ferredoxins, Citrus fruit ferredoxin clustered together with root ferredoxins and separated from the photosynthetic ferredoxins. Non photosynthetic (root and fruit) ferredoxins, but not the photosynthetic ferredoxins, have their closest homologs in cyanobacteria. Analysis of ferredoxin genomic organization suggested that non-photosynthetic ferredoxins exist in Citrus as a small gene family. Expression of Fd1 is developmentally regulated during flower opening and fruit maturation, both processes may be mediated by ethylene in Citrus. Exogenous ethylene application also induced the expression of Fd1 both in flavedo and leaves. The induction on non-photosynthetic ferredoxins could be related with the demand for reducing power in non-green, but biosynthetically active, tissues.
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Affiliation(s)
- J M Alonso
- Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas, Spain
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Kamide K, Sakai H, Aoki K, Sanada Y, Wada K, Green LS, Yee BC, Buchanan BB. Amino acid sequences of heterotrophic and photosynthetic ferredoxins from the tomato plant (Lycopersicon esculentum Mill.). PHOTOSYNTHESIS RESEARCH 1995; 46:301-308. [PMID: 24301596 DOI: 10.1007/bf00020444] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/1995] [Accepted: 05/31/1995] [Indexed: 06/02/2023]
Abstract
Several forms (isoproteins) of ferredoxin in roots, leaves, and green and red pericarps in tomato plants (Lycopersicon esculentum Mill.) were earlier identified on the basis of N-terminal amino acid sequence and chromatographic behavior (Green et al. 1991). In the present study, a large scale preparation made possible determination of the full length amino acid sequence of the two ferredoxins from leaves. The ferredoxins characteristic of fruit and root were sequenced from the amino terminus to the 30th residue or beyond. The leaf ferredoxins were confirmed to be expressed in pericarp of both green and red fruit. The ferredoxins characteristic of fruit and root appeared to be restricted to those tissue. The results extend earlier findings in demonstrating that ferredoxin occurs in the major organs of the tomato plant where it appears to function irrespective of photosynthetic competence.
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Affiliation(s)
- K Kamide
- Department of Biology, Faculty of Science, Kanazawa University, Kakuma, 920-11, Kanazawa, Japan
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García-Gutiérrez A, Cantón FR, Gallardo F, Sánchez-Jiménez F, Cánovas FM. Expression of ferredoxin-dependent glutamate synthase in dark-grown pine seedlings. PLANT MOLECULAR BIOLOGY 1995; 27:115-128. [PMID: 7865781 DOI: 10.1007/bf00019183] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Pine seedlings are able to accumulate chlorophylls and develop green plastids in a light-independent manner. In this work, we have characterized ferredoxin-dependent glutamate synthase (EC 1.4.7.1; Fd-GOGAT), a key enzyme in nitrogen interconversion during this process. Fd-GOGAT has been purified about 170-fold from cotyledons of maritime pine (Pinus pinaster). As occurs in angiosperms, the native enzyme is a single polypeptide with an apparent molecular mass of 163-168 kDa that is confined to the chloroplast stroma. Polyclonal antibodies generated against the purified enzyme were used to immunoscreen a lambda gt11 expression library from Scots pine (Pinus sylvestris) seedlings and partial cDNA clones were isolated and characterized. The clone with the longest cDNA insert (pGOP44) contained the codification for the C-terminal (550 amino acids) of the pine Fd-GOGAT polypeptide. Immunological cross-reactivity and comparative amino sequence analysis revealed that Fd-GOGAT is a well conserved protein in higher plants. Western blot analyses showed that protein was expressed in chloroplast-containing pine tissues and this expression pattern was not affected by exogenously supplied nitrogen. Fd-GOGAT mRNA, polypeptide and enzyme activity accumulated in substantial amounts in dark-grown pine seedlings. The presence of a functional Fd-GOGAT may be important to provide the required glutamate for the biosynthesis of nitrogen compounds during chloroplast biogenesis in the dark.
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Affiliation(s)
- A García-Gutiérrez
- Laboratorio de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Málaga, Spain
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Camara B, Hugueney P, Bouvier F, Kuntz M, Monéger R. Biochemistry and molecular biology of chromoplast development. INTERNATIONAL REVIEW OF CYTOLOGY 1995; 163:175-247. [PMID: 8522420 DOI: 10.1016/s0074-7696(08)62211-1] [Citation(s) in RCA: 125] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Plant cells contain a unique class of organelles, designated the plastids, which distinguish them from animal cells. According to the largely accepted endosymbiotic theory of evolution, plastids are descendants of prokaryotes. This process requires several adaptative changes which involve the maintenance and the expression of part of the plastid genome, as well as the integration of the plastid activity to the cellular metabolism. This is illustrated by the diversity of plastids encountered in plant cells. For instance, in tissues undergoing color changes, i.e., flowers and fruits, the chromoplasts produce and accumulate excess carotenoids. In this paper we attempt to review the basic aspects of chromoplast development.
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Affiliation(s)
- B Camara
- Institut de Biologie Moléculaire des Plantes du Centre National de la Recherche Scientifique, Strasbourg, France
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Ritchie SW, Redinbaugh MG, Shiraishi N, Vrba JM, Campbell WH. Identification of a maize root transcript expressed in the primary response to nitrate: characterization of a cDNA with homology to ferredoxin-NADP+ oxidoreductase. PLANT MOLECULAR BIOLOGY 1994; 26:679-690. [PMID: 7948922 DOI: 10.1007/bf00013753] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
To more fully understand the biochemical and molecular events which occur in plants exposed to nitrate, cDNAs whose accumulation was enhanced in nitrate- and cycloheximide-treated maize (Zea mays L. W64A x W182E) roots were isolated. The 340 bp Zmrprn1 (for Zea mays root primary response to nitrate) cDNA also hybridized with a probe enriched for nitrate-induced sequences, and was characterized further. Sequence analysis of a near full-length cDNA (Zmrprn1A) showed strong homology (> 90% amino acid identity) with a root ferredoxin-NADP+ oxidoreductase (FNR) of rice, and 45-50% amino acid identify with leaf FNR genes. When expressed in Escherichia coli, the Zmrprn1A cDNA produced a protein with NADPH: ferricyanide reductase activity, consistent with the enzymatic properties of an FNR. The Zmrprn1 cDNA hybridized with a 1.4 kb transcript which was expressed in the maize root primary response to nitrate. That is, mRNA levels in roots increased rapidly and transiently in response to external nitrate, and low levels of nitrate (10 microM) induced transcript accumulation. The accumulation of the Zmrprn1 transcript was not prevented by cycloheximide, indicating that the cellular factor(s) required for expression were constitutively present in maize roots. The Zmrprn1 mRNA accumulated specifically in response to nitrate, since neither K+ nor NH4+ treatment of roots caused transcript accumulation. Maize leaves had about 5% of the transcript level found in roots, indicating a strong preference for expression of Zmrprn1 in roots. Analysis of maize genomic DNA indicated the presence of only a single gene or very small gene family for the Zmrprn1. Together, the data indicate that Zmrprn1A encodes a nitrate regulated maize root FNR.
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Affiliation(s)
- S W Ritchie
- USDA-ARS Crops Research Laboratory, Oxford, NC
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Aoki H, Ida S. Nucleotide sequence of a rice root ferredoxin-NADP+ reductase cDNA and its induction by nitrate. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1183:553-6. [PMID: 8286405 DOI: 10.1016/0005-2728(94)90085-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A ferredoxin-NADP+ reductase (FNR) cDNA was isolated from a lambda gt 11 cDNA library constructed from the roots of nitrate-induced rice (Oryza sativa L. cv. Kinmaze) seedlings. The nucleotide sequence of this clone contains a 1134 nucleotide open reading frame. The N-terminal 62 amino acid stretch was assigned to the transit sequence, followed by 316 residues for the mature protein. The rice root FNR shows only 49% sequence identity to that of the leaf enzyme, but the regions of the binding sites to ferredoxin, NADP-PPi and NADP+ are highly conserved between the two enzymes. The root FNR mRNA was induced transiently by the addition of nitrate, but not by ammonia. The results support the view that the root FNR is involved in the nitrate assimilation in nonchlorophyllous tissues.
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Affiliation(s)
- H Aoki
- Research Institute for Food Science, Kyoto University, Japan
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Morigasaki S, Jin T, Wada K. Comparative Studies on Ferredoxin-NADP+ Oxidoreductase Isoenzymes Derived from Different Organs by Antibodies Specific for the Radish Root- and Leaf-Enzymes. PLANT PHYSIOLOGY 1993; 103:435-440. [PMID: 12231952 PMCID: PMC159001 DOI: 10.1104/pp.103.2.435] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Determination of the prosthetic group and titration of sulfhydryl group of ferredoxin-NADP+ oxidoreductase (FNR) from roots of radish (Raphanus sativus var acanthiformis cv Miyashige) confirmed its similarity to leaf-FNR. Antisera directed against radish root-FNR and leaf-FNR distinguished the enzyme forms from roots and leaves of radish as well as other flowering plants. The FNR isoenzymes showed organ-specific distributions. In horsetail (Equisetum arvense L.) and cultured liverwort cells (Marchantia polymorpha), at least two FNR isoenzymes were distinguished by the antisera. FNR from Chlorella vulgaris reacted only with the anti-root-FNR antiserum. FNR from a cyanobacterium, Spirulina spp., failed to react with either antiserum.
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Affiliation(s)
- S. Morigasaki
- Department of Biology, Faculty of Science, Kanazawa University, Kakuma, Kanazawa, Ishikawa 920-11 Japan
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