Search

Your search keyword '"MESH: Thylakoids"' showing total 7 results
Start Over Descriptor "MESH: Thylakoids"
7 results on '"MESH: Thylakoids"'

1. Developmentally regulated association of plastid division protein FtsZ1 with thylakoid membranes in Arabidopsis thaliana

Author

El-Sayed El-Kafafi, Silva Lerbs-Mache, Isabelle Pignot-Paintrand, Mohamed Karamoko, Paul Mandaron, Denis Falconet, Didier Grunwald, Plastes et différenciation cellulaire (PDC), Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherches sur les Macromolécules Végétales (CERMAV), Université Joseph Fourier - Grenoble 1 (UJF)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ANTE-INSERM U836, équipe 4, Muscles et pathologies, Transduction du signal : signalisation calcium, phosphorylation et inflammation, Université Joseph Fourier - Grenoble 1 (UJF)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Joseph Fourier - Grenoble 1 (UJF)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de la Santé et de la Recherche Médicale (INSERM), This work was supported by a grant [ACIDRAB (ActionConcertée Incitative-Dynamique et Réactivité des Assemblages Biologiques) 03/41, number 03 5 90 to D. F. and number 03 5 92 to I.P.-P.] from the CNRS and the MEN (Ministère de l'Education Nationale), by the Egyptian government (fellowship toE.-S. E.-K.), and by the Ivory Coast government (fellowship to M.K.)., Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Plastes et Différenciation Cellulaire, Université Joseph Fourier and CNRS, Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Alexandre, France, and Baudier, Jacques

Subjects
Chlorophyll, 0106 biological sciences, Chloroplasts, Plastid localization, Arabidopsis thaliana, Mutant, Arabidopsis, Thylakoids, 01 natural sciences, Biochemistry, MESH: Thylakoids, Gene Expression Regulation, Plant, chloroplast division, MESH: Microscopy, Confocal, [SDV.BV] Life Sciences [q-bio]/Vegetal Biology, MESH: Arabidopsis, Plastids, ComputingMilieux_MISCELLANEOUS, Plant Proteins, 2. Zero hunger, 0303 health sciences, Microscopy, Confocal, MESH: Plant Proteins, biology, Stem Cells, Life Sciences, food and beverages, thylakoid membrane, MESH: Plastids, Immunohistochemistry, Cell biology, Chloroplast, Phenotype, Thylakoid, MESH: Microscopy, Electron, Transmission, MESH: Chlorophyll, FtsZ gene family, MESH: Arabidopsis Proteins, MESH: Stem Cells, [SDV.BC]Life Sciences [q-bio]/Cellular Biology, macromolecular substances, MESH: Phenotype, Models, Biological, 03 medical and health sciences, Microscopy, Electron, Transmission, plastid localization, [SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, Gene family, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, MESH: Gene Expression Regulation, Plant, Plastid, FtsZ, [SDV.BC] Life Sciences [q-bio]/Cellular Biology, Molecular Biology, 030304 developmental biology, Organelles, MESH: Chloroplasts, Arabidopsis Proteins, MESH: Models, Biological, MESH: Immunohistochemistry, Cell Biology, biology.organism_classification, plastid division, biology.protein, MESH: Organelles, 010606 plant biology & botany
Abstract

International audience; FtsZ is a key protein involved in bacterial and organellar division. Bacteria have only one ftsZ gene, while chlorophytes (higher plants and green alga) have two distinct FtsZ gene families, named FtsZ1 and FtsZ2. This raises the question of why chloroplasts in these organisms need distinct FtsZ proteins to divide. In order to unravel new functions associated with FtsZ proteins, we have identified and characterized an Arabidopsis thaliana FtsZ1 loss-of-function mutant. ftsZ1-knockout mutants are impeded in chloroplast division, and division is restored when FtsZ1 is expressed at a low level. FtsZ1-overexpressing plants show a drastic inhibition of chloroplast division. Chloroplast morphology is altered in ftsZ1, with chloroplasts having abnormalities in the thylakoid membrane network. Overexpression of FtsZ1 also induced defects in thylakoid organization with an increased network of twisting thylakoids and larger grana. We show that FtsZ1, in addition to being present in the stroma, is tightly associated with the thylakoid fraction. This association is developmentally regulated since FtsZ1 is found in the thylakoid fraction of young developing plant leaves but not in mature and old plant leaves. Our results suggest that plastid division protein FtsZ1 may have a function during leaf development in thylakoid organization, thus highlighting new functions for green plastid FtsZ.

Published
2007

2. Fibrillin influence on plastid ultrastructure and pigment content in tomato fruit

Author

Joël Gaffé, Paul D. Fraser, Andrew J. Simkin, Peter M. Bramley, Jean-Pierre Carde, Marcel Kuntz, Jean-Pierre Alcaraz, Laboratoire Adaptation et pathogénie des micro-organismes [Grenoble] (LAPM), Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Gestes Medico-chirurgicaux Assistés par Ordinateur (TIMC-IMAG-GMCAO), Techniques de l'Ingénierie Médicale et de la Complexité - Informatique, Mathématiques et Applications, Grenoble - UMR 5525 (TIMC-IMAG), VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Plastes et différenciation cellulaire (PDC), European commission Agriculture and Fisheries program for the mobility of researchers (Contract No. FAIR-98-5002), Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-IMAG-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-IMAG-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Laboratoire de physiologie cellulaire végétale (LPCV), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Recherche Agronomique (INRA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
0106 biological sciences, Plastoglobule, macromolecular substances, Plant Science, MESH: Capsicum, Horticulture, Biology, Fibrillins, Thylakoids, Chloroplast, 01 natural sciences, Biochemistry, MESH: Microfilament Proteins, 03 medical and health sciences, MESH: Thylakoids, Solanum lycopersicum, Membrane pore, MESH: Lycopersicon esculentum, Chromoplast, Plastids, Lycopersicon esculentum, Thylakoid integrity, Plastid, Molecular Biology, Carotenoid, 030304 developmental biology, chemistry.chemical_classification, 0303 health sciences, [SDV.BID.EVO]Life Sciences [q-bio]/Biodiversity/Populations and Evolution [q-bio.PE], Microfilament Proteins, food and beverages, Ripening, MESH: Plastids, General Medicine, Plants, Genetically Modified, Fruit ripening, Carotenoids, MESH: Plants, Genetically Modified, chemistry, Fruit, Thylakoid, MESH: Carotenoids, Capsicum, MESH: Fruit, Fibrillin, 010606 plant biology & botany
Abstract

International audience; The protein termed fibrillin is involved in the formation of lipoprotein structures, such as plastoglobules and fibrils in certain chromoplast types, which have been implicated in the over-production of pigments due to a sink effect. In order to examine its effect in differentiating chromoplasts of a non-fibrillar type, the pepper fibrillin gene was expressed in tomato fruit. Both the transcript and protein were found to accumulate during tomato fruit ripening from an early mature green stage. However, formation of carotenoid deposition structures in tomato chromoplasts, such as fibrils, was not observed. Nevertheless, a two-fold increase in carotenoid content and associated carotenoid derived flavour volatiles (6-methyl-5-hepten-2-one, geranylacetone, beta-ionone and beta-cyclocitral) was observed. An unexpected phenotypic observation in the transgenic fruit was the delayed loss of thylakoids in differentiating chromoplasts, leading to the transient formation of plastids exhibiting a typical chromoplastic zone adjacent to a protected chloroplastic zone with preserved thylakoids. An in vitro assay has been developed to monitor fibrillin activity on thylakoids: data were obtained suggesting a membrane protection role for fibrillin, more specifically against moderate uncoupling effects.

Published
2007

3. Kinetics of structural reorganizations in multilamellar photosynthetic membranes monitored by small-angle neutron scattering

Author

Ottó Zsiros, Gergely Nagy, László Almásy, Peter Timmins, Győző Garab, László Kovács, Dorthe Posselt, Renáta Ünnep, Judith Peters, László Rosta, Institut Laue-Langevin (ILL), ILL, Dept Biol, University of Missouri [Columbia] (Mizzou), University of Missouri System-University of Missouri System, Wigner Research Centre for Physics [Budapest], Hungarian Academy of Sciences (MTA), Institute of Plant Biology, Biological Research Centre [Budapest] (BRC), Hungarian Academy of Sciences (MTA)-Hungarian Academy of Sciences (MTA), Department of Genetics, Southwest Foundation for Biomedical Research, Department of Data Management, Eo¨tvo¨s Lora'nd Geophysical Institute of Hungary, Geophysical Institute of Hungary, Institut de biologie structurale (IBS - UMR 5075 ), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
0106 biological sciences, Materials science, Kinetics, Biophysics, Neutron scattering, Photosynthesis, 01 natural sciences, Thylakoids, 03 medical and health sciences, Nuclear magnetic resonance, MESH: Thylakoids, Spinacia oleracea, Scattering, Small Angle, General Materials Science, MESH: Scattering, Small Angle, 030304 developmental biology, 0303 health sciences, MESH: Kinetics, [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Structural Biology [q-bio.BM], MESH: Spinacia oleracea, food and beverages, Time resolution, Surfaces and Interfaces, General Chemistry, Intracellular Membranes, Small-angle neutron scattering, MESH: Neutron Diffraction, MESH: Intracellular Membranes, Neutron Diffraction, Membrane, Thylakoid, lipids (amino acids, peptides, and proteins), 010606 plant biology & botany, Biotechnology
Abstract

International audience; We demonstrate the power of time-resolved small-angle neutron scattering experiments for the investigation of the structure and structural reorganizations of multilamellar photosynthetic membranes. In addition to briefly summarizing our results on thylakoid membranes isolated from higher plants and in unicellular organisms, we discuss the advantages and technical and methodological limitations of time-resolved SANS. We present a detailed and more systematical investigation of the kinetics of light-induced structural reorganizations in isolated spinach thylakoid membranes, which show how changes in the repeat distance and in the long-range order of the multilamellar membranes can be followed with a time resolution of seconds. We also present data from comparative measurements performed on thylakoid membranes isolated from tobacco.

Published
2012

4. Thylakoid potassium channel is required for efficient photosynthesis in cyanobacteria

Author

Nicoletta La Rocca, Vanessa Checchetto, Giovanni Finazzi, Ildikò Szabò, Guillaume Allorent, Nobuyuki Uozumi, Anna Segalla, Giorgio M. Giacometti, Elisabetta Bergantino, Luigi Leanza, Department of Biology, University of Padova, Universita degli Studi di Padova, Laboratoire de physiologie cellulaire végétale (LPCV), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de la Recherche Agronomique (INRA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Department of Biomolecular Engineering, Tohoku University, Tohoku University [Sendai], Italian Ministry for University and Research Fondo Integrativo Speciale Ricerca (FISR) grant, Grants-in-Aid for Scientific Research 22380056 and 24658090 from the Ministry for Education, Culture, Sport, Science and Technology, Japan Society for the Promotion of Science, Japanese Society of Technology (JST) Strategic Project on Marine Genome and Marine Biotechnology, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Recherche Agronomique (INRA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Padova = University of Padua (Unipd), Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Recherche Agronomique (INRA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
0106 biological sciences, Chlorophyll, Potassium Channels, Photosystem II, bioenergetics, MESH: Synechocystis, 01 natural sciences, Thylakoids, cyanobacteria, Membrane Potentials, Gene Knockout Techniques, MESH: Thylakoids, MESH: Bacterial Proteins, MESH: Photosynthesis, Photosystem, MESH: Gene Knockout Techniques, 0303 health sciences, Multidisciplinary, Cytochrome b6f complex, potassium, MESH: Photosystem II Protein Complex, Synechocystis, thylakoid membrane, MESH: Potassium Channels, Biological Sciences, Biochemistry, Thylakoid, Protons, MESH: Chlorophyll, MESH: Oxygen, ion flux, MESH: Photosystem I Protein Complex, Photosynthetic Reaction Center Complex Proteins, Biology, Photosystem I, Electron Transport, 03 medical and health sciences, Bacterial Proteins, Light-dependent reactions, MESH: Membrane Potentials, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, Electrochemical gradient, MESH: Electron Transport, 030304 developmental biology, photosynthesis, Photosystem I Protein Complex, Photosystem II Protein Complex, biology.organism_classification, Oxygen, MESH: Photosynthetic Reaction Center Complex Proteins, Biophysics, MESH: Protons, membrane potential, 010606 plant biology & botany
Abstract

A potassium channel (SynK) of the cyanobacterium Synechocystis sp. PCC 6803, a photoheterotrophic model organism for the study of photosynthesis, has been recently identified and demonstrated to function as a potassium selective channel when expressed in a heterologous system and to be located predominantly to the thylakoid membrane in cyanobacteria. To study its physiological role, a SynK-less knockout mutant was generated and characterized. Fluorimetric experiments indicated that SynK-less cyanobacteria cannot build up a proton gradient as efficiently as WT organisms, suggesting that SynK might be involved in the regulation of the electric component of the proton motive force. Accordingly, measurements of flash-induced cytochrome b 6 f turnover and respiration pointed to a reduced generation of ΔpH and to an altered linear electron transport in mutant cells. The lack of the channel did not cause an altered membrane organization, but decreased growth and modified the photosystem II/photosystem I ratio at high light intensities because of enhanced photosensitivity. These data shed light on the function of a prokaryotic potassium channel and reports evidence, by means of a genetic approach, on the requirement of a thylakoid ion channel for optimal photosynthesis.

Published
2012

5. Interplay between N-terminal methionine excision and FtsH protease is essential for normal chloroplast development and function in Arabidopsis

Author

Frédéric Frottin, Thierry Meinnel, Zach Adam, Carmela Giglione, Christelle Espagne, Institut des sciences du végétal (ISV), and Centre National de la Recherche Scientifique (CNRS)

Subjects
0106 biological sciences, Chlorophyll, MESH: Amidohydrolases, Chloroplasts, Light, medicine.medical_treatment, Arabidopsis, Plant Science, 01 natural sciences, Thylakoids, Methionine, MESH: Thylakoids, ATP-Dependent Proteases, Protein biosynthesis, Arabidopsis thaliana, MESH: Arabidopsis, Research Articles, 0303 health sciences, medicine.diagnostic_test, biology, MESH: Photosystem II Protein Complex, Chloroplast, MESH: Plant Leaves, Phenotype, Biochemistry, MESH: Protein Biosynthesis, MESH: Membrane Proteins, MESH: Chlorophyll, Proteases, Proteolysis, MESH: Proteolysis, MESH: Arabidopsis Proteins, Protein degradation, MESH: Phenotype, Models, Biological, Amidohydrolases, 03 medical and health sciences, MESH: ATP-Dependent Proteases, medicine, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, 030304 developmental biology, Protease, MESH: Chloroplasts, Arabidopsis Proteins, MESH: Models, Biological, Membrane Proteins, Photosystem II Protein Complex, Cell Biology, biology.organism_classification, MESH: Light, Plant Leaves, Mutagenesis, Insertional, MESH: Mutagenesis, Insertional, Seedlings, Protein Biosynthesis, MESH: Protein Processing, Post-Translational, MESH: Methionine, MESH: Seedling, Protein Processing, Post-Translational, 010606 plant biology & botany
Abstract

N-terminal methionine excision (NME) is the earliest modification affecting most proteins. All compartments in which protein synthesis occurs contain dedicated NME machinery. Developmental defects induced in Arabidopsis thaliana by NME inhibition are accompanied by increased proteolysis. Although increasing evidence supports a connection between NME and protein degradation, the identity of the proteases involved remains unknown. Here we report that chloroplastic NME (cNME) acts upstream of the FtsH protease complex. Developmental defects and higher sensitivity to photoinhibition associated with the ftsh2 mutation were abolished when cNME was inhibited. Moreover, the accumulation of D1 and D2 proteins of the photosystem II reaction center was always dependent on the prior action of cNME. Under standard light conditions, inhibition of chloroplast translation induced accumulation of correctly NME-processed D1 and D2 in a ftsh2 background, implying that the latter is involved in protein quality control, and that correctly NME-processed D1 and D2 are turned over primarily by the thylakoid FtsH protease complex. By contrast, inhibition of cNME compromises the specific N-terminal recognition of D1 and D2 by the FtsH complex, whereas the unprocessed forms are recognized by other proteases. Our results highlight the tight functional interplay between NME and the FtsH protease complex in the chloroplast.

Published
2011

6. Intraplastidial trafficking of a phage-type RNA polymerase is mediated by a thylacoïd RING-H2 protein

Author

Silva Lerbs-Mache, Thierry Lagrange, Mohamed-Ali Hakimi, Pankaj Jaiswal, Florence Courtois, Emilie Demarsy, Laurence Maréchal-Drouard, Jacinthe Azevedo, Jean-Pierre Alcaraz, Institut de biologie moléculaire des plantes (IBMP), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Plastes et différenciation cellulaire (PDC), Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Laboratoire Adaptation et pathogénie des micro-organismes [Grenoble] (LAPM), Center for Integrative Genomics - Institute of Bioinformatics, Génopode (CIG), Swiss Institute of Bioinformatics [Lausanne] (SIB), Université de Lausanne (UNIL)-Université de Lausanne (UNIL), Laboratoire Génome et développement des plantes (LGDP), Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), Department of Plant Breeding and Genetics, Cornell University [New York], and Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)

Subjects
0106 biological sciences, Light, Arabidopsis, MESH: Amino Acid Sequence, Thylakoids, 01 natural sciences, chemistry.chemical_compound, MESH: Saccharomyces cerevisiae Proteins, MESH: Thylakoids, Gene Expression Regulation, Plant, Transcription (biology), RNA, Ribosomal, 16S, RNA polymerase, MESH: Arabidopsis, Bacteriophages, Promoter Regions, Genetic, MESH: Organ Specificity, 0303 health sciences, Multidisciplinary, food and beverages, MESH: Transcription Factors, DNA-Directed RNA Polymerases, Biological Sciences, Transport protein, Cell biology, MESH: RNA, Ribosomal, 16S, DNA-Binding Proteins, Chloroplast, MESH: Promoter Regions (Genetics), MESH: Intracellular Membranes, Protein Transport, Transmembrane domain, Organ Specificity, Thylakoid, Protein Binding, MESH: Protein Transport, Saccharomyces cerevisiae Proteins, Molecular Sequence Data, MESH: Arabidopsis Proteins, [SDV.BC]Life Sciences [q-bio]/Cellular Biology, Biology, MESH: Two-Hybrid System Techniques, DNA-binding protein, 03 medical and health sciences, Two-Hybrid System Techniques, MESH: Gene Library, MESH: Protein Binding, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, MESH: Bacteriophages, Amino Acid Sequence, RNA, Messenger, MESH: Gene Expression Regulation, Plant, Plastid, MESH: RNA, Messenger, Gene Library, 030304 developmental biology, MESH: Molecular Sequence Data, Arabidopsis Proteins, Intracellular Membranes, Molecular biology, MESH: Light, MESH: DNA-Directed RNA Polymerases, chemistry, Transcription Factors, 010606 plant biology & botany
Abstract

The plastid genome of dicotyledonous plants is transcribed by three different RNA polymerases; an eubacterial-type enzyme, PEP; and two phage-type enzymes, RPOTp and RPOTmp. RPOTp plays an important role in chloroplast transcription, biogenesis, and mesophyll cell proliferation. RPOTmp fulfills a specific function in the transcription of the rrn operon in proplasts/amyloplasts during seed imbibition/germination and a more general function in chloroplasts during later developmental stages. In chloroplasts, RPOTmp is tightly associated with thylakoid membranes indicating that functional switching of RPOTmp is connected to thylakoid association. By using the yeast two-hybrid system, we have identified two proteins that interact with RPOTmp. The two proteins are very similar, both characterized by three N-terminal transmembrane domains and a C-terminal RING domain. We show that at least one of these proteins is an intrinsic thylakoid membrane protein that fixes RPOTmp on the stromal side of the thylakoid membrane, probably via the RING domain. A model is presented in which light by triggering the synthesis of the RING protein determines membrane association and functional switching of RPOTmp.

Published
2008

7. Redox Modulation of Cyclic Electron Flow around Photosystem I in C3 Plants †

Author

Pierre Joliot, Giles N. Johnson, Beena Nandha, Giovanni Finazzi, Cécile Breyton, Institut de biologie structurale (IBS - UMR 5075 ), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Physiologie membranaire et moléculaire du chloroplaste (PMMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Collège de France (CdF (institution)), Physico-chimie moléculaire des membranes biologiques (PCMMB), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de biologie structurale (IBS - UMR 5075), Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Physiologie cellulaire et végétale (LPCV), Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Chlorophyll, 0106 biological sciences, Photosynthetic reaction centre, MESH: Oxidation-Reduction, MESH: Photosystem I Protein Complex, Photosystem II, Photochemistry, Photosystem I, Thylakoids, 01 natural sciences, Biochemistry, Electron Transport, 03 medical and health sciences, MESH: Thylakoids, Spinacia oleracea, Light-dependent reactions, MESH: Electron Transport, 030304 developmental biology, Photosystem, 0303 health sciences, P700, Photosystem I Protein Complex, biology, [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Structural Biology [q-bio.BM], Chemistry, Cytochrome b6f complex, MESH: Spinacia oleracea, MESH: Cytochrome b6f Complex, food and beverages, biology.organism_classification, Adaptation, Physiological, MESH: Adaptation, Physiological, Plant Leaves, MESH: Plant Leaves, [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biomolecules [q-bio.BM], Cytochrome b6f Complex, Spinach, Oxidation-Reduction, MESH: Chlorophyll, 010606 plant biology & botany
Abstract

International audience; We have investigated the occurrence of cyclic electron flow in intact spinach leaves. In particular, we have tested the hypothesis that cyclic flow requires the presence of supercomplexes in the thylakoid membrane or other strong associations between proteins. Using biochemical approaches, we found no evidence of the presence of supercomplexes related to cyclic electron flow, making previous structural explanations for the modulation of cyclic flow rather unlikely. On the other hand, we found that the fraction of photosystem I complexes engaged in cyclic flow could be modulated by changes in the redox state of the chloroplast stroma. Our findings support therefore a dynamic model for the occurrence of linear and cyclic electron flow in C3 plants, based on the competition between cytochrome b(6)f and FNR for electrons carried by ferredoxin. This would be ultimately regulated by the balance between the redox state of PSI acceptors and donors during photosynthesis, in a diffusing system.

Published
2006

Catalog

Books, media, physical & digital resources
See catalog results