99 results on '"Bourguet E"'
Search Results
2. PRECLINICAL EVALUATION OF NEW HDAC INHIBITORS IN ANIMAL MODELS OF ALCOHOL USE DISORDERS
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Naassila, Mickael, Jeanblanc, Jérôme, Bourguet, E., Groupe de Recherche sur l'alcool et les pharmacodépendances - UMR INSERM_S 1247 (GRAP), Université de Picardie Jules Verne (UPJV)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), and DESSAIVRE, Louise more...
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[SDV] Life Sciences [q-bio] ,[SDV]Life Sciences [q-bio] - Abstract
19th World Congress of International-Society-for-Biomedical-Research-on-Alcoholism (ISBRA), Kyoto, JAPAN, SEP 09-13, 2018; International audience
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- 2018
Catalog
3. INSCRIPTION DE MAGNÉSIE DU MÉANDRE
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Bourguet, E.
- Published
- 1900
4. Programme R-Mines : impact des espèces invasives sur les reptiles des massifs miniers : rapport final
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Jourdan, Hervé, Brescia, F., Vidal, Eric, Bourguet, E. (collab.), Cateine, M. (collab.), Debar, L. (collab.), Geimer, C. (collab.), Lindsay, S. (collab.), Méringo, H. de (collab.), Manceau, M. (collab.), Martin, J. (collab.), Muret, E. (collab.), Sadlier, R. (collab.), Saint-Germès, N. (collab.), Rigault, F. (collab.), and Thibault, M. (collab.) more...
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CONSERVATION DE LA NATURE ,ESPECE MENACEE ,CHAT HARET ,CONSEQUENCE ECOLOGIQUE ,FONCTIONNEMENT DE L'ECOSYSTEME ,INTRODUCTION D'ESPECES - Published
- 2015
5. Neutrophil elastase as a target in lung cancer
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Moroy, Gautier, A.J.P., Alix, Hornebeck, W., Bourguet, E., Matrice extracellulaire et dynamique cellulaire - UMR 7369 (MEDyC), SFR CAP Santé (Champagne-Ardenne Picardie Santé), Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS), Origine, structure et évolution de la biodiversité (OSEB), and Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS) more...
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ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2012
6. Effect of Madex® (codling moth granulovirus) on Cydia pomonella (L.) egg laying on two apple varieties: relationships with plant surface metabolites
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Lombarkia, N., Ioriatti, C., Bourguet, E., and Derridj, S.
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- 2007
7. Effect of a Granulovirus Larvicide, Madex®, on Egg-Laying ofCydia pomonellaL. (Lepidoptera: Tortricidae) Due to Changes in Chemical Signalization on the Apple Leaf Surface
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Lombarkia, N., primary, Derridj, S., additional, Ioriatti, C., additional, and Bourguet, E., additional
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- 2013
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8. Looking forward: A glance into the future of organic chemistry
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Compain, P, Desvergnes, V, Ollivier, C, Robert, F, Suzenet, F, Barboiu, M, Belmont, P, Bleeriot, Y, Bolze, F, Bouquillon, S, Bourguet, E, Braida, B, Constantieux, T, Desaubry, L, Dupont, D, Stephane, G, Jerome, F, Legoupy, S, Marat, X, Marie, M, Moitessier, N, Papot, S, Peri, F, Petit, M, Py, S, Schulz, E, Isabelle, T, Vauzeilles, B, Philippe, V, Vergnes, L, Vidal, S, Wilmouth, S, Isabelle, TO, Wilmouth, S., PERI, FRANCESCO, Compain, P, Desvergnes, V, Ollivier, C, Robert, F, Suzenet, F, Barboiu, M, Belmont, P, Bleeriot, Y, Bolze, F, Bouquillon, S, Bourguet, E, Braida, B, Constantieux, T, Desaubry, L, Dupont, D, Stephane, G, Jerome, F, Legoupy, S, Marat, X, Marie, M, Moitessier, N, Papot, S, Peri, F, Petit, M, Py, S, Schulz, E, Isabelle, T, Vauzeilles, B, Philippe, V, Vergnes, L, Vidal, S, Wilmouth, S, Isabelle, TO, Wilmouth, S., and PERI, FRANCESCO more...
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What will organic chemistry do in the next forty years? This Perspective lists six tasks that have emerged during the first edition of ESYOP, a symposium devoted to the future of organic 14 chemistry. The collective answer presented has been elaborated following a 4-step process: stimulating plenary lectures given by outstanding chemists and philosophers, short presentations given by each participant (average age: 34 years old), think-tank sessions and writing of the final report after the symposium. more...
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- 2006
9. Photochemical rearrangement of oxaziridines and nitrones in the hexahydroindole series: A convenient synthetic route to 1-azabicyclo[5.2.0]nonan-2-ones as novel RGD mimetics
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UCL - SC/CHIM - Département de chimie, Bourguet, E, Declercq, Jean-Paul, Baneres, JL, Girard, JP., Parello, J., Vidal, JP., Lusinchi, X, UCL - SC/CHIM - Département de chimie, Bourguet, E, Declercq, Jean-Paul, Baneres, JL, Girard, JP., Parello, J., Vidal, JP., and Lusinchi, X more...
- Abstract
GRAPHICS Photolysis of oxaziridines a or nitrones b provides a convenient synthetic route to fused bicyclic lactams c adequately substituted on both cycles A and B as scaffolds for mimicking conformationally constrained beta -turn peptides as in the tripeptide RGD signaling motif of fibronectin. more...
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- 2001
10. Light-activation of NADP-malate dehydrogenase: A highly controlled process for an optimized function
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Miginiac-Maslow, M., primary, Johansson, K., additional, Ruelland, E., additional, Issakidis-Bourguet, E., additional, Schepens, I., additional, Goyer, A., additional, Lemaire-Chamley, M., additional, Jacquot, J.-P., additional, Le Marechal, P., additional, and Decottignies, P., additional more...
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- 2000
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11. Der Kult und die Mysterien von Eleusis Leo Bloch
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Bourguet, E.
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- 1897
12. De l'idée de la mort en Grèce à l'époque classique A. de Ridder
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Bourguet, E.
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- 1897
13. Étude chronologique sur la troisième guerre sacrée (356-346 av. J.-C). Thèse complémentaire présentée à la Faculté des Lettres Paul CLOCHÉ
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Bourguet, E.
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- 1916
14. Photochemical Rearrangement of Oxaziridines and Nitrones in the Hexahydroindole Series: A Convenient Synthetic Route to 1-Azabicyclo[5.2.0]nonan-2-ones as Novel RGD Mimetics
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Bourguet, E., Baneres, J.-L., Girard, J.-P., Parello, J., Vidal, J.-P., Lusinchi, X., and Declercq, J.-P.
- Abstract
Photolysis of oxaziridines more...a or nitronesb provides a convenient synthetic route to fused bicyclic lactamsc adequately substituted on both cycles A and B as scaffolds for mimicking conformationally constrained β-turn peptides as in the tripeptide RGD signaling motif of fibronectin.- Published
- 2001
15. Integration and expression of Sorghum C4 phosphoenolpyruvate carboxylase and chloroplastic NADP+-malate dehydrogenase separately or together in C3 potato plants
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Beaujean, A., Issakidis-Bourguet, E., Catterou, M., Dubois, F., Sangwan, R. S., and Sangwan-Norreel, B. S.
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- 2001
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16. Direct NMR observation of the thioredoxin-mediated reduction of the chloroplast NADP-malate dehydrogenase provides a structural basis for the relief of autoinhibition.
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Krimm, I, Goyer, A, Issakidis-Bourguet, E, Miginiac-Maslow, M, and Lancelin, J M
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The chloroplastic NADP-dependent malate dehydrogenase (NADP-MDH) catalyzing the reduction of oxaloacetate into L-malate is regulated by light. Its activation results from the thioredoxin-mediated reduction of two disulfides, located, respectively, in N- and C-terminal sequence extensions typical of all NADP-dependent light-regulated forms. Site-directed mutagenesis studies and the resolution of the three-dimensional structure of the oxidized (inactive) Sorghum vulgare enzyme showed that the C-terminal Cys(365)-Cys(377) disulfide constrains the C-terminal extension to fold into the active site where it acts as an internal inhibitor. In the present study, two-dimensional proton NMR spectra of an engineered NADP-MDH rendered monomeric by a 33-amino acid deletion at the N terminus (38 kDa) revealed that a 15-amino acid-long C-terminal peptide (Ala(375) to C-terminal Val(389)) acquired an increased mobility upon reduction, allowing its direct sequence-specific NMR assignment. The location of the flexible peptide in the sequence suggests that the first part of the C-terminal peptide is still folded near the core of the enzyme, so that cysteines 365 and 377 remain in proximity to allow for an efficient reoxidation/inactivation of the enzyme. more...
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- 1999
17. The internal Cys-207 of sorghum leaf NADP-malate dehydrogenase can form mixed disulphides with thioredoxin
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Goyer, A., Decottignies, P., Lemaire, S., Ruelland, E., Issakidis-Bourguet, E., Jacquot, J.-P., and Miginiac-Maslow, M.
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- 1999
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18. An internal cysteine is involved in the thioredoxin-dependent activation of sorghum leaf NADP-malate dehydrogenase.
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Ruelland, E, Lemaire-Chamley, M, Le Maréchal, P, Issakidis-Bourguet, E, Djukic, N, and Miginiac-Maslow, M
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The chloroplastic NADP-malate dehydrogenase is activated by thiol/disulfide interchange with reduced thioredoxins. Previous experiments showed that four cysteines located in specific N- and carboxyl-terminal extensions were implicated in this process, leading to a model where no internal cysteine was involved in activation. In the present study, the role of the conserved four internal cysteines was investigated. Surprisingly, the mutation of cysteine 207 into alanine yielded a protein with accelerated activation time course, whereas the mutations of the three other internal cysteines into alanines yielded proteins with unchanged activation kinetics. These results suggested that cysteine 207 might be linked in a disulfide bridge with one of the four external cysteines, most probably with one of the two amino-terminal cysteines whose mutation similarly accelerates the activation rate. To investigate this possibility, mutant malate dehydrogenases (MDHs) where a single amino-terminal cysteine was mutated in combination with the mutation of both carboxyl-terminal cysteines were produced and purified. The C29S/C365A/C377A mutant MDH still needed activation by reduced thioredoxin, while the C24S/C365A/C377A mutant MDH exhibited a thioredoxin-insensitive spontaneous activity, leading to the hypothesis that a Cys24-Cys207 disulfide bridge might be formed during the activation process. Indeed, an NADP-MDH where the cysteines 29, 207, 365, and 377 are mutated yielded a permanently active enzyme very similar to the previously created permanently active C24S/C29S/C365A/C377A mutant. A two-step activation model involving a thioredoxin-mediated disulfide isomerization at the amino terminus is proposed. more...
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- 1997
19. Infection by chikungunya virus modulates the expression of several proteins in Aedes aegypti salivary glands
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Tchankouo-Nguetcheu Stephane, Bourguet Edouard, Lenormand Pascal, Rousselle Jean-Claude, Namane Abdelkader, and Choumet Valerie
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Aedes aegypti ,Chikungunya virus ,Mosquito salivary gland ,Proteomics ,Two-dimensional gel electrophoresis ,Mass spectrometry ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Arthropod-borne viral infections cause several emerging and resurging infectious diseases. Among the diseases caused by arboviruses, chikungunya is responsible for a high level of severe human disease worldwide. The salivary glands of mosquitoes are the last barrier before pathogen transmission. Methods We undertook a proteomic approach to characterize the key virus/vector interactions and host protein modifications that occur in the salivary glands that could be responsible for viral transmission by using quantitative two-dimensional electrophoresis. Results We defined the protein modulations in the salivary glands of Aedes aegypti that were triggered 3 and 5 days after an oral infection (3 and 5 DPI) with chikungunya virus (CHIKV). Gel profile comparisons showed that CHIKV at 3 DPI modulated the level of 13 proteins, and at 5 DPI 20 proteins. The amount of 10 putatively secreted proteins was regulated at both time points. These proteins were implicated in blood-feeding or in immunity, but many have no known function. CHIKV also modulated the quantity of proteins involved in several metabolic pathways and in cell signalling. Conclusion Our study constitutes the first analysis of the protein response of Aedes aegypti salivary glands infected with CHIKV. We found that the differentially regulated proteins in response to viral infection include structural proteins and enzymes for several metabolic pathways. Some may favour virus survival, replication and transmission, suggesting a subversion of the insect cell metabolism by arboviruses. For example, proteins involved in blood-feeding such as the short D7, an adenosine deaminase and inosine-uridine preferring nucleoside hydrolase, may favour virus transmission by exerting an increased anti-inflammatory effect. This would allow the vector to bite without the bite being detected. Other proteins, like the anti-freeze protein, may support vector protection. more...
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- 2012
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20. Effect of a Granulovirus Larvicide, Madex®, on Egg-Laying of Cydia pomonella L. (Lepidoptera: Tortricidae) Due to Changes in Chemical Signalization on the Apple Leaf Surface
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Lombarkia, N., Derridj, S., Ioriatti, C., and Bourguet, E.
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- 2013
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21. Thioredoxin-regulated β-amylase (BAM1) triggers diurnal starch degradation in guard cells, and in mesophyll cells under osmotic stress
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Francesca Sparla, Paolo Trost, Lucia Marri, Concetta Valerio, Emmanuelle Issakidis-Bourguet, Alex Costa, Paolo Pupillo, Valerio C., Costa A., Marri L., Issakidis-Bourguet E., Pupillo P., Trost P., and Sparla F. more...
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Osmosis ,Thioredoxin-Disulfide Reductase ,Disulphide ,Osmotic shock ,Physiology ,Starch ,Arabidopsis ,thiol-based redox regulation ,Plant Science ,Protein Serine-Threonine Kinases ,Gene Expression Regulation, Enzymologic ,Chloroplast Thioredoxins ,chemistry.chemical_compound ,Gene Expression Regulation, Plant ,Stress, Physiological ,DEHYDRATION ,Guard cell ,Arabidopsis thaliana ,Amylase ,biology ,Arabidopsis Proteins ,starch ,fungi ,CHLOROPLAST ,ARABIDOPSIS THALIANA ,food and beverages ,biology.organism_classification ,Research Papers ,STOMATA ,Cell biology ,Plant Leaves ,YELLOW FLUORESCENT PROTEIN ,REDOX SIGNALLING ,Chloroplast ,chemistry ,Biochemistry ,redox ,Plant Stomata ,Osmoregulation ,biology.protein ,guard cell ,Thioredoxin ,osmoregulation - Abstract
BAM1 is a plastid-targeted β-amylase of Arabidopsis thaliana specifically activated by reducing conditions. Among eight different chloroplast thioredoxin isoforms, thioredoxin f1 was the most efficient redox mediator, followed by thioredoxins m1, m2, y1, y2, and m4. Plastid-localized NADPH-thioredoxin reductase (NTRC) was also able partially to restore the activity of oxidized BAM1. Promoter activity of BAM1 was studied by reporter gene expression (GUS and YFP) in Arabidopsis transgenic plants. In young (non-flowering) plants, BAM1 was expressed both in leaves and roots, but expression in leaves was mainly restricted to guard cells. Compared with wild-type plants, bam1 knockout mutants were characterized by having more starch in illuminated guard cells and reduced stomata opening, suggesting that thioredoxin-regulated BAM1 plays a role in diurnal starch degradation which sustains stomata opening. Besides guard cells, BAM1 appears in mesophyll cells of young plants as a result of a strongly induced gene expression under osmotic stress, which is paralleled by an increase in total β-amylase activity together with its redox-sensitive fraction. Osmotic stress impairs the rate of diurnal starch accumulation in leaves of wild-type plants, but has no effect on starch accumulation in bam1 mutants. It is proposed that thioredoxin-regulated BAM1 activates a starch degradation pathway in illuminated mesophyll cells upon osmotic stress, similar to the diurnal pathway of starch degradation in guard cells that is also dependent on thioredoxin-regulated BAM1. more...
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- 2010
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22. Prompt and Easy Activation by Specific Thioredoxins of Calvin Cycle Enzymes of Arabidopsis thaliana Associated in the GAPDH/CP12/PRK Supramolecular Complex
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Francesca Sparla, Lucia Marri, Valérie Collin, Stéphane D. Lemaire, Paolo Trost, Emmanuelle Issakidis-Bourguet, Myroslawa Miginiac-Maslow, Paolo Pupillo, Mirko Zaffagnini, MARRI L., ZAFFAGNINI M., COLLIN V., ISSAKIDIS-BOURGUET E., LEMAIRE S.D., PUPILLO P., SPARLA F., MIGINIAC-MASLOW M., and TROST P. more...
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chemistry.chemical_classification ,biology ,Phosphoribulokinase ,Arabidopsis ,Glyceraldehyde-3-Phosphate Dehydrogenases ,Dehydrogenase ,Plant Science ,biology.organism_classification ,Chloroplast ,Thioredoxins ,Enzyme ,chemistry ,Biochemistry ,Chromatography, Gel ,biology.protein ,Thermodynamics ,Arabidopsis thaliana ,Thioredoxin ,Molecular Biology ,Glyceraldehyde 3-phosphate dehydrogenase - Abstract
The Calvin cycle enzymes glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and phosphoribulokinase (PRK) can form under oxidizing conditions a supramolecular complex with the regulatory protein CP12. Both GAPDH and PRK activities are inhibited within the complex, but they can be fully restored by reduced thioredoxins (TRXs). We have investigated the interactions of eight different chloroplast thioredoxin isoforms (TRX f1, m1, m2, m3, m4, y1, y2, x) with GAPDH (A 4 , B 4 , and B 8 isoforms), PRK and CP12 (isoform 2), all from Arabidopsis thaliana . In the complex, both A 4 -GAPDH and PRK were promptly activated by TRX f1, or more slowly by TRXs m1 and m2, but all other TRXs were ineffective. Free PRK was regulated by TRX f1, m1, or m2, while B 4 - and B 8 -GAPDH were absolutely specific for TRX f1. Interestingly, reductive activation of PRK caged in the complex was much faster than reductive activation of free oxidized PRK, and activation of A 4 -GAPDH in the complex was much faster (and less demanding in terms of reducing potential) than activation of free oxidized B 4 - or B 8 -GAPDH. It is proposed that CP12-assembled supramolecular complex may represent a reservoir of inhibited enzymes ready to be released in fully active conformation following reduction and dissociation of the complex by TRXs upon the shift from dark to low light. On the contrary, autonomous redox-modulation of GAPDH (B-containing isoforms) would be more suited to conditions of very active photosynthesis. more...
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- 2009
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23. Redox regulation of chloroplastic glucose-6-phosphate dehydrogenase: a new role for f-type thioredoxin
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Paolo Trost, Guillaume Née, Emmanuelle Issakidis-Bourguet, Mirko Zaffagnini, NEE G., ZAFFAGNINI M., TROST P., and ISSAKIDIS-BOURGUET E.
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Models, Molecular ,animal structures ,Chloroplasts ,Light ,Biophysics ,Arabidopsis ,Dehydrogenase ,Oxidative phosphorylation ,Pentose phosphate pathway ,Biology ,Glucosephosphate Dehydrogenase ,Oxidative pentose phosphate pathway ,Biochemistry ,chemistry.chemical_compound ,Chloroplast Thioredoxins ,Structural Biology ,Genetics ,Glucose-6-phosphate dehydrogenase ,Cysteine ,Molecular Biology ,Ferredoxin ,chemistry.chemical_classification ,Arabidopsis Proteins ,Plastidial thioredoxin ,Cell Biology ,Darkness ,biology.organism_classification ,Recombinant Proteins ,Cell biology ,Protein Structure, Tertiary ,Isoenzymes ,Enzyme ,chemistry ,Redox regulation ,Ferredoxins ,Thioredoxin ,Oxidation-Reduction - Abstract
Glucose-6-phosphate dehydrogenase (G6PDH) is the key enzyme of the oxidative pentose phosphate pathway supplying reducing power (as NADPH) in non-photosynthesizing cells. We have examined in detail the redox regulation of the plastidial isoform predominantly present in Arabidopsis green tissues (AtG6PDH1) and found that its oxidative activation is strictly dependent on plastidial thioredoxins (Trxs) that show differential efficiencies. Light/dark modulation of AtG6PDH1 was reproduced in vitro in a reconstituted ferredoxin/Trx system using f-type Trx allowing to propose a new function for this Trx isoform co-ordinating both reductive (Calvin cycle) and oxidative pentose phosphate pathways. more...
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- 2009
24. Thioredoxins in chloroplasts
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Stéphane D. Lemaire, Mirko Zaffagnini, Emmanuelle Issakidis-Bourguet, Vincent Massot, Laure Michelet, Lemaire SD, Michelet L, Zaffagnini M, Massot V, and Issakidis-Bourguet E.
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Proteomics ,animal structures ,Chloroplasts ,Sequence alignment ,Genome ,Models, Biological ,Thioredoxins ,Arabidopsis ,Glutaredoxin ,Genetics ,Animals ,Protein Isoforms ,Glutaredoxins ,Plant Proteins ,biology ,Chlamydomonas ,General Medicine ,biology.organism_classification ,Glutathione ,Chloroplast ,Molecular Weight ,Biochemistry ,Thioredoxin ,Oxidoreductases ,Oxidation-Reduction ,Sequence Alignment ,Metabolic Networks and Pathways ,Signal Transduction - Abstract
Thioredoxins (TRXs) are small disulfide oxidoreductases of ca. 12 kDa found in all free living organisms. In plants, two chloroplastic TRXs, named TRX f and TRX m, were originally identified as light dependent regulators of several carbon metabolism enzymes including Calvin cycle enzymes. The availability of genome sequences revealed an unsuspected multiplicity of TRXs in photosynthetic eukaryotes, including new chloroplastic TRX types. Moreover, proteomic approaches and focused studies allowed identification of 90 potential chloroplastic TRX targets. Lately, recent studies suggest the existence of a complex interplay between TRXs and other redox regulators such as glutaredoxins (GRXs) or glutathione. The latter is involved in a post-translational modification, named glutathionylation that could be controlled by GRXs. Glutathionylation appears to specifically affect the activity of TRX f and other chloroplastic enzymes and could thereby constitute a previously undescribed regulatory mechanism of photosynthetic metabolism under oxidative stress. After summarizing the initial studies on TRX f and TRX m, this review will focus on the most recent developments with special emphasis on the contributions of genomics and proteomics to the field of TRXs. Finally, new emerging interactions with other redox signaling pathways and perspectives for future studies will also be discussed. more...
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- 2007
25. Thioredoxins, glutaredoxins, and glutathionylation: new crosstalks to explore
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Emmanuelle Issakidis-Bourguet, Hélène Vanacker, Laure Michelet, Myroslawa Miginiac-Maslow, Mirko Zaffagnini, Vincent Massot, Stéphane D. Lemaire, Eliane Keryer, Michelet L, Zaffagnini M, Massot V, Keryer E, Vanacker H, Miginiac-Maslow M, Issakidis-Bourguet E, and Lemaire SD. more...
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chemistry.chemical_classification ,Reactive oxygen species ,biology ,Disulfide bond ,Cell Biology ,Plant Science ,General Medicine ,Glutathione ,GLUTAREDOXIN ,biology.organism_classification ,Protein glutathionylation ,Biochemistry ,Redox ,Cell biology ,chemistry.chemical_compound ,Thioredoxins ,chemistry ,Arabidopsis ,Glutaredoxin ,Thioredoxin ,Oxidoreductases ,Oxidation-Reduction ,Glutaredoxins ,Signal Transduction - Abstract
Oxidants are widely considered as toxic molecules that cells have to scavenge and detoxify efficiently and continuously. However, emerging evidence suggests that these oxidants can play an important role in redox signaling, mainly through a set of reversible post-translational modifications of thiol residues on proteins. The most studied redox system in photosynthetic organisms is the thioredoxin (TRX) system, involved in the regulation of a growing number of target proteins via thiol/disulfide exchanges. In addition, recent studies suggest that glutaredoxins (GRX) could also play an important role in redox signaling especially by regulating protein glutathionylation, a post-translational modification whose importance begins to be recognized in mammals while much less is known in photosynthetic organisms. This review focuses on oxidants and redox signaling with particular emphasis on recent developments in the study of functions, regulation mechanisms and targets of TRX, GRX and glutathionylation. This review will also present the complex emerging interplay between these three components of redox-signaling networks. more...
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- 2006
26. Looking forward : a glance into the future of organic chemistry
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Xavier Marat, Delphine Dupont, Francesco Peri, Frédéric Robert, Sébastien Papot, Emmanuelle Schulz, Isabelle Tranoy-Opalinski, Erika Bourguet, Sandrine Py, Cyril Ollivier, Yves Blériot, Laurent Vergnes, François Jérôme, Boris Vauzeilles, Benoît Braïda, Mihail Barboiu, Valérie Desvergnes, Serge Wilmouth, Marc Petit, Franck Suzenet, Nicolas Moitessier, Stéphanie Legoupy, Sandrine Bouquillon, Philippe Belmont, Marie E. Migaud, Laurent Désaubry, Frédéric Bolze, Philippe Compain, Stéphane Gastaldi, Philippe Vayron, Thierry Constantieux, Sébastien Vidal, Institut de Chimie Organique et Analytique (ICOA), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Chirotechnologies : Catalyse et Biocatalyse (CCB), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie organique et organométallique (LCOO), Université Sciences et Technologies - Bordeaux 1 (UB)-Centre National de la Recherche Scientifique (CNRS), Institut Européen des membranes (IEM), Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Méthodologie de synthèse et molécules bioactives (MSMB), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Biomolécules : synthèse, structure et mode d'action (UMR 8642) (BIOSYMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Moléculaire de Reims - UMR 7312 (ICMR), Université de Reims Champagne-Ardenne (URCA)-Institut de Chimie du CNRS (INC)-SFR CAP Santé (Champagne-Ardenne Picardie Santé), Université de Reims Champagne-Ardenne (URCA)-Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS)-SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS), Isolement, structure, transformations et synthèse de substances naturelles (ISTSSN), Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie théorique (LCT), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), SYnthèse, Modèles, Implications BIOlogiques (SYMBIO), Université de la Méditerranée - Aix-Marseille 2-Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS), Substances naturelles/chimie moléculaire, Université Louis Pasteur - Strasbourg I-Ecole européenne de chimie, polymères et matériaux [Strasbourg]-Centre National de la Recherche Scientifique (CNRS), LVMH Recherche, LVMH Moët Hennessy Louis Vuitton, Chimie, biologie et radicaux libres - UMR 6517 (CBRL), Université de la Méditerranée - Aix-Marseille 2-Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Centre National de la Recherche Scientifique (CNRS), Laboratoire de catalyse en chimie organique (LACCO), Université de Poitiers-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Unité de chimie organique moléculaire et macromoléculaire (UCO2M), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), L'OREAL Recherche avancée, L'OREAL, Queen's University [Belfast] (QUB), McGill University = Université McGill [Montréal, Canada], Synthèse et réactivité des substances naturelles (SRSN), Dipartemento di biotecnologie e Bioscienze, Università degli Studi di Milano-Bicocca = University of Milano-Bicocca (UNIMIB), Laboratoire de Synthèse Organique (Hétérochimie organique, organoéléments et matériaux) (LSOHOOM), Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études dynamiques et structurales de la sélectivité (LEDSS), Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Sanofi Aventis, Sanofi-Aventis, Centre de recherche Pierre Fabre, PIERRE FABRE, Organon, Laboratoire d'innovation moléculaire et applications (LIMA), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Méthodes et Application en Chimie Organique (MACO), Institut Parisien de Chimie Moléculaire (IPCM), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Technologies nouvelles et éducation (TECNE), INRP, Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie des Milieux et Matériaux de Poitiers (IC2MP), Université de Poitiers-Centre National de la Recherche Scientifique (CNRS), Conception et application de molécules bioactives (CAMB), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-SFR CAP Santé (Champagne-Ardenne Picardie Santé), Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institut des Sciences Moléculaires de Marseille (ISM2), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Institut universitaire de formation des maîtres - Nord-Pas-de-Calais (IUFM Nord-Pas-de-Calais), Université d'Artois (UA), Institut de Chimie Radicalaire (ICR), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), MOLTECH-Anjou, Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS), Queen's University, Queen's University [Kingston], Structure et Réactivité des Systèmes Moléculaires Complexes (SRSMC), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Synthèse Organique (E5), Université de Poitiers-Centre National de la Recherche Scientifique (CNRS)-Université de Poitiers-Centre National de la Recherche Scientifique (CNRS), Department of Biotechnology and Biosciences, University of Milano-Bicocca, Supélec Sciences des Systèmes [Gif-sur-Yvette] (E3S), SUPELEC, Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Chimie Organique 2-Glycochimie (CO2GLYCO), Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Supérieure Chimie Physique Électronique de Lyon-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Supérieure Chimie Physique Électronique de Lyon-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université d'Orléans (UO)-Institut de Chimie du CNRS (INC), Université Sciences et Technologies - Bordeaux 1-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paul Cézanne - Aix-Marseille 3-Université de la Méditerranée - Aix-Marseille 2, Université de Poitiers-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Università degli Studi di Milano-Bicocca [Milano] (UNIMIB), Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS), Demorgny, Patricia, Compain, P, Desvergnes, V, Ollivier, C, Robert, F, Suzenet, F, Barboiu, M, Belmont, P, Bleeriot, Y, Bolze, F, Bouquillon, S, Bourguet, E, Braida, B, Constantieux, T, Desaubry, L, Dupont, D, Stephane, G, Jerome, F, Legoupy, S, Marat, X, Marie, M, Moitessier, N, Papot, S, Peri, F, Petit, M, Py, S, Schulz, E, Isabelle, T, Vauzeilles, B, Philippe, V, Vergnes, L, Vidal, S, Wilmouth, S, Centre National de la Recherche Scientifique (CNRS)-Université Paul Cézanne - Aix-Marseille 3, École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Réactions sélectives et applications (RSA), Université de Reims Champagne-Ardenne (URCA), Centre National de la Recherche Scientifique (CNRS)-Université de Provence - Aix-Marseille 1-Université Paul Cézanne - Aix-Marseille 3-Université de la Méditerranée - Aix-Marseille 2, Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS), McGill University, Centre National de la Recherche Scientifique (CNRS)-Université de Poitiers, Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), and Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU) more...
- Subjects
010405 organic chemistry ,Process (engineering) ,Chemistry ,Perspective (graphical) ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Catalysis ,0104 chemical sciences ,ESYOP, organic chemistry ,CHIM/06 - CHIMICA ORGANICA ,[CHIM] Chemical Sciences ,Materials Chemistry ,Organic chemistry ,[CHIM]Chemical Sciences ,ComputingMilieux_MISCELLANEOUS - Abstract
What will organic chemistry do in the next forty years? This Perspective lists six tasks that have emerged during the first edition of ESYOP, a symposium devoted to the future of organic 14 chemistry. The collective answer presented has been elaborated following a 4-step process: stimulating plenary lectures given by outstanding chemists and philosophers, short presentations given by each participant (average age: 34 years old), think-tank sessions and writing of the final report after the symposium. more...
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- 2006
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27. A complex and dynamic redox network regulates oxygen reduction at photosystem I in Arabidopsis.
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Hani U, Naranjo B, Shimakawa G, Espinasse C, Vanacker H, Sétif P, Rintamäki E, Issakidis-Bourguet E, and Krieger-Liszkay A
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- Mutation genetics, Plant Leaves metabolism, Plant Leaves genetics, Reactive Oxygen Species metabolism, Photoperiod, Thioredoxins metabolism, Thioredoxins genetics, NADP metabolism, Light, Arabidopsis metabolism, Arabidopsis genetics, Photosystem I Protein Complex metabolism, Oxidation-Reduction, Oxygen metabolism, Thylakoids metabolism, Arabidopsis Proteins metabolism, Arabidopsis Proteins genetics
- Abstract
Thiol-dependent redox regulation of enzyme activities plays a central role in regulating photosynthesis. Besides the regulation of metabolic pathways, alternative electron transport is subjected to thiol-dependent regulation. We investigated the regulation of O2 reduction at photosystem I. The level of O2 reduction in leaves and isolated thylakoid membranes depends on the photoperiod in which plants are grown. We used a set of Arabidopsis (Arabidopsis thaliana) mutant plants affected in the stromal, membrane, and lumenal thiol network to study the redox protein partners involved in regulating O2 reduction. Light-dependent O2 reduction was determined in leaves and thylakoids of plants grown in short-day and long-day conditions using a spin-trapping electron paramagnetic resonance assay. In wild-type samples from short-day conditions, reactive oxygen species generation was double that of samples from long-day conditions, while this difference was abolished in several redoxin mutants. An in vitro reconstitution assay showed that thioredoxin m, NADPH-thioredoxin reductase C, and NADPH are required for high O2-reduction levels in thylakoids from plants grown in long-day conditions. Using isolated photosystem I, we also showed that reduction of a photosystem I protein is responsible for the increase in O2 reduction. Furthermore, differences in the membrane localization of m-type thioredoxins and 2-Cys peroxiredoxin were detected between thylakoids of short-day and long-day plants. Overall, we propose a model of redox regulation of O2 reduction according to the reduction power of the stroma and the ability of different thiol-containing proteins to form a network of redox interactions., Competing Interests: Conflict of interest statement. None declared., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Society of Plant Biologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.) more...
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- 2024
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28. A Semi-throughput Procedure for Assaying Plant NADP-malate Dehydrogenase Activity Using a Plate Reader.
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Baudry K and Issakidis-Bourguet E
- Abstract
Chloroplast NADP-dependent malate dehydrogenase (NADP-MDH) is a redox regulated enzyme playing an important role in plant redox homeostasis. Leaf NADP-MDH activation level is considered a proxy for the chloroplast redox status. NADP-MDH enzyme activity is commonly assayed spectrophotometrically by following oxaloacetate-dependent NADPH oxidation at 340 nm. We have developed a plate-adapted protocol to monitor NADP-MDH activity allowing faster data production and lower reagent consumption compared to the classic cuvette format of a spectrophotometer. We provide a detailed procedure to assay NADP-MDH activity and measure the enzyme activation state in purified protein preparations or in leaf extracts. This protocol is provided together with a semi-automatized data analysis procedure using an R script., Competing Interests: Competing interestsThe authors declare no conflict of interest., (©Copyright : © 2023 The Authors; This is an open access article under the CC BY-NC license.) more...
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- 2023
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29. Thioredoxins m regulate plastid glucose-6-phosphate dehydrogenase activity in Arabidopsis roots under salt stress.
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Née G, Wang F, Châtel-Innocenti G, Mhamdi A, Juranville E, Vanacker H, Noctor G, and Issakidis-Bourguet E
- Abstract
Plants contain several NADPH-producing enzymes including glucose-6-phosphate dehydrogenases (G6PDH) with different sub-cellular localizations. The activity of plastidial G6PDHs is redox-regulated by thioredoxins (TRX). Although specific TRXs are known to regulate chloroplastic isoforms of G6PDH, little information is available for plastidic isoforms found in heterotrophic organs or tissues. Here, we investigated TRX regulation of the two G6PDH plastidic isoforms of Arabidopsis roots during exposure to a mild salt stress. We report that in vitro m-type TRXs are the most efficient regulators of the G6PDH2 and G6PDH3 mainly found in Arabidopsis roots. While expression of the corresponding G6PD and plastidic TRX genes was marginally affected by salt, it impaired root growth of several of the corresponding mutant lines. Using an in situ assay for G6PDH, G6PDH2 was found to be the major contributor to salt-induced increases in activity, while data from ROS assays further provide in vivo evidence that TRX m acts in redox regulation during salt stress. Taken together, our data suggest that regulation of plastid G6PDH activity by TRX m may be an important player regulating NADPH production in Arabidopsis roots undergoing salt stress., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Née, Wang, Châtel-Innocenti, Mhamdi, Juranville, Vanacker, Noctor and Issakidis-Bourguet.) more...
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- 2023
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30. S-Nitrosylation of the histone deacetylase HDA19 stimulates its activity to enhance plant stress tolerance in Arabidopsis.
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Zheng Y, Li Z, Cui X, Yang Z, Bao C, Pan L, Liu X, Chatel-Innocenti G, Vanacker H, Noctor G, Dard A, Reichheld JP, Issakidis-Bourguet E, and Zhou DX
- Subjects
- Histone Deacetylases genetics, Histone Deacetylases metabolism, Chromatin metabolism, Nitric Oxide metabolism, Arabidopsis metabolism, Arabidopsis Proteins genetics, Arabidopsis Proteins metabolism
- Abstract
Arabidopsis histone deacetylase HDA19 is required for gene expression programs of a large spectrum of plant developmental and stress-responsive pathways. How this enzyme senses cellular environment to control its activity remains unclear. In this work, we show that HDA19 is post-translationally modified by S-nitrosylation at 4 Cysteine (Cys) residues. HDA19 S-nitrosylation depends on the cellular nitric oxide level, which is enhanced under oxidative stress. We find that HDA19 is required for cellular redox homeostasis and plant tolerance to oxidative stress, which in turn stimulates its nuclear enrichment, S-nitrosylation and epigenetic functions including binding to genomic targets, histone deacetylation and gene repression. The Cys137 of the protein is involved in basal and stress-induced S-nitrosylation, and is required for HDA19 functions in developmental, stress-responsive and epigenetic controls. Together, these results indicate that S-nitrosylation regulates HDA19 activity and is a mechanism of redox-sensing for chromatin regulation of plant tolerance to stress., (© 2023 Society for Experimental Biology and John Wiley & Sons Ltd.) more...
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- 2023
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31. Adenylates regulate Arabidopsis plastidial thioredoxin activities through the binding of a CBS domain protein.
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Baudry K, Barbut F, Domenichini S, Guillaumot D, Thy MP, Vanacker H, Majeran W, Krieger-Liszkay A, Issakidis-Bourguet E, and Lurin C
- Subjects
- Adenosine Monophosphate metabolism, Adenosine Triphosphate metabolism, Chloroplast Proteins metabolism, Chloroplasts metabolism, Cystathionine beta-Synthase chemistry, Oxidation-Reduction, Plastids metabolism, Sulfhydryl Compounds metabolism, Thioredoxins genetics, Thioredoxins metabolism, Arabidopsis genetics, Arabidopsis metabolism, Arabidopsis Proteins metabolism
- Abstract
Cystathionine-β-synthase (CBS) domains are found in proteins of all living organisms and have been proposed to play a role as energy sensors regulating protein activities through their adenosyl ligand binding capacity. In plants, members of the CBSX protein family carry a stand-alone pair of CBS domains. In Arabidopsis (Arabidopsis thaliana), CBSX1 and CBSX2 are targeted to plastids where they have been proposed to regulate thioredoxins (TRXs). TRXs are ubiquitous cysteine thiol oxido-reductases involved in the redox-based regulation of numerous enzymatic activities as well as in the regeneration of thiol-dependent peroxidases. In Arabidopsis, 10 TRX isoforms have been identified in plastids and divided into five sub-types. Here, we show that CBSX2 specifically inhibits the activities of m-type TRXs toward two chloroplast TRX-related targets. By testing activation of NADP-malate dehydrogenase and reduction of 2-Cys peroxiredoxin, we found that TRXm1/2 inhibition by CBSX2 was alleviated in the presence of AMP or ATP. We also determined, by pull-down assays, a direct interaction of CBSX2 with reduced TRXm1 and m2 that was abolished in the presence of adenosyl ligands. In addition, we report that, compared with wild-type plants, the Arabidopsis T-DNA double mutant cbsx1 cbsx2 exhibits growth and chlorophyll accumulation defects in cold conditions, suggesting a function of plastidial CBSX proteins in plant stress adaptation. Together, our results show an energy-sensing regulation of plastid TRX m activities by CBSX, possibly allowing a feedback regulation of ATP homeostasis via activation of cyclic electron flow in the chloroplast, to maintain a high energy level for optimal growth., (© American Society of Plant Biologists 2022. All rights reserved. For permissions, please email: journals.permissions@oup.com.) more...
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- 2022
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32. Human Neuraminidases: Structures and Stereoselective Inhibitors.
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Bourguet E, Figurska S, and Fra Czek MM
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- Amino Acid Sequence, Humans, Models, Molecular, Neuraminidase classification, Stereoisomerism, Structure-Activity Relationship, Enzyme Inhibitors pharmacology, Neuraminidase antagonists & inhibitors, Neuraminidase chemistry
- Abstract
This Perspective describes the classification, structures, substrates, mechanisms of action, and implications of human neuraminidases (hNEUs) in various pathologies. Some inhibitors have been developed for each isoform, leading to more precise interactions with hNEUs. Although crystal structure data are available for NEU2, most of the findings are based on NEU1 inhibition, and limited information is available for other hNEUs. Therefore, the synthesis of new compounds would facilitate the enrichment of the arsenal of inhibitors to better understand the roles of hNEUs and their mechanisms of action. Nevertheless, due to the already known inhibitors of human neuraminidase enzymes, a structure-activity relationship is presented along with different approaches to inhibit these enzymes for the development of potent and selective inhibitors. Among the different emerging strategies, one is the inhibition of the dimerization of NEU1 or NEU3, and the second is the inhibition of certain receptors located close to hNEU. more...
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- 2022
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33. A Simplified Method to Assay Protein Carbonylation by Spectrophotometry.
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Moreau C and Issakidis-Bourguet E
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- Oxidation-Reduction, Protein Carbonylation, Spectrophotometry, Oxidative Stress, Proteins
- Abstract
Protein carbonylation is an irreversible oxidation process leading to a loss of function of carbonylated proteins. Carbonylation is largely considered as a hallmark of oxidative stress, the level of protein carbonylation being an indicator of the oxidative cellular status. The method described herein represents an adaptation to the commonly used 2,4-dinitrophenylhydrazine (DNPH)-based spectrophotometric method to monitor protein carbonylation level. The classical final sample precipitation was replaced by a gel filtration step avoiding the tedious and repetitive washings of the protein pellet to remove free DNPH while allowing optimal protein recovery.This improved protocol here implemented to assay protein carbonylation in plant leaves can potentially be used with any cellular extract., (© 2022. Springer Science+Business Media, LLC, part of Springer Nature.) more...
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- 2022
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34. A New Role for Plastid Thioredoxins in Seed Physiology in Relation to Hormone Regulation.
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Née G, Châtel-Innocenti G, Meimoun P, Leymarie J, Montrichard F, Satour P, Bailly C, and Issakidis-Bourguet E
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- Arabidopsis genetics, Arabidopsis Proteins genetics, Germination, Plant Growth Regulators genetics, Plastids genetics, Seeds growth & development, Thioredoxins genetics, Arabidopsis metabolism, Arabidopsis Proteins biosynthesis, Gene Expression Regulation, Plant, Plant Growth Regulators metabolism, Plastids metabolism, Seeds metabolism, Thioredoxins biosynthesis
- Abstract
In Arabidopsis seeds, ROS have been shown to be enabling actors of cellular signaling pathways promoting germination, but their accumulation under stress conditions or during aging leads to a decrease in the ability to germinate. Previous biochemical work revealed that a specific class of plastid thioredoxins (Trxs), the y-type Trxs, can fulfill antioxidant functions. Among the ten plastidial Trx isoforms identified in Arabidopsis, Trx y1 mRNA is the most abundant in dry seeds. We hypothesized that Trx y1 and Trx y2 would play an important role in seed physiology as antioxidants. Using reverse genetics, we found important changes in the corresponding Arabidopsis mutant seeds. They display remarkable traits such as increased longevity and higher and faster germination in conditions of reduced water availability or oxidative stress. These phenotypes suggest that Trxs y do not play an antioxidant role in seeds, as further evidenced by no changes in global ROS contents and protein redox status found in the corresponding mutant seeds. Instead, we provide evidence that marker genes of ABA and GAs pathways are perturbed in mutant seeds, together with their sensitivity to specific hormone inhibitors. Altogether, our results suggest that Trxs y function in Arabidopsis seeds is not linked to their previously identified antioxidant roles and reveal a new role for plastid Trxs linked to hormone regulation. more...
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- 2021
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35. Metabolic control of histone demethylase activity involved in plant response to high temperature.
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Cui X, Zheng Y, Lu Y, Issakidis-Bourguet E, and Zhou DX
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- Arabidopsis genetics, Gene Expression Regulation, Plant, Genetic Variation, Genotype, Mutation, Plants, Genetically Modified genetics, Plants, Genetically Modified metabolism, Arabidopsis Proteins genetics, Arabidopsis Proteins metabolism, Histone Demethylases genetics, Histone Demethylases metabolism, Hot Temperature adverse effects, Stress, Physiological genetics, Stress, Physiological physiology
- Abstract
Jumonji C (JmjC) domain proteins are histone lysine demethylases that require ferrous iron and alpha-ketoglutarate (or α-KG) as cofactors in the oxidative demethylation reaction. In plants, α-KG is produced by isocitrate dehydrogenases (ICDHs) in different metabolic pathways. It remains unclear whether fluctuation of α-KG levels affects JmjC demethylase activity and epigenetic regulation of plant gene expression. In this work, we studied the impact of loss of function of the cytosolic ICDH (cICDH) gene on the function of histone demethylases in Arabidopsis thaliana. Loss of cICDH resulted in increases of overall histone H3 lysine 4 trimethylation (H3K4me3) and enhanced mutation defects of the H3K4me3 demethylase gene JMJ14. Genetic analysis suggested that the cICDH mutation may affect the activity of other demethylases, including JMJ15 and JMJ18 that function redundantly with JMJ14 in the plant thermosensory response. Furthermore, we show that mutation of JMJ14 affected both the gene activation and repression programs of the plant thermosensory response and that JMJ14 and JMJ15 repressed a set of genes that are likely to play negative roles in the process. The results provide evidence that histone H3K4 demethylases are involved in the plant response to elevated ambient temperature., (© American Society of Plant Biologists 2021. All rights reserved. For permissions, please email: journals.permissions@oup.com.) more...
- Published
- 2021
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36. Targeting Class IIa HDACs: Insights from Phenotypes and Inhibitors.
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Liu L, Dong L, Bourguet E, and Fairlie DP
- Subjects
- Ligands, Phenotype, Structure-Activity Relationship, Histone Deacetylase Inhibitors pharmacology, Histone Deacetylases metabolism
- Abstract
This review summarizes key literature defining the phenotypes of individual class IIa HDAC proteins and compounds that selectively target their enzymatic catalytic domain (CD). The focus is on the effects of class IIa HDACs in physiological and pathological conditions, both in vitro and in vivo, and on their mode of action in regulating genes, upstream proteins and signaling pathways. Phenotype studies further demonstrate either beneficial or detrimental effects of silencing selected class IIa HDACs or their enzymatic properties. We also summarize the knowledge gained from structure-activity relationships of CD inhibitors as well as molecular mechanisms underpinning isozyme selectivity where crystal structures or modelling studies are available. Given that the number of genes affected by silencing class IIa HDACs is much smaller than class I, the role of gene regulation of class IIa HDACs could be much more selective. Since class IIa HDACs have restricted tissue distributions and multiple functions independent of their CD, targeting the CD of class IIa HDACs could lead to more selective therapeutic agents with significantly fewer side-effects than other HDAC ligands., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.) more...
- Published
- 2021
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37. Arabidopsis histone deacetylase HDA15 directly represses plant response to elevated ambient temperature.
- Author
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Shen Y, Lei T, Cui X, Liu X, Zhou S, Zheng Y, Guérard F, Issakidis-Bourguet E, and Zhou DX
- Subjects
- Arabidopsis metabolism, Arabidopsis Proteins genetics, Biosynthetic Pathways genetics, Chromatin Assembly and Disassembly physiology, DNA-Binding Proteins genetics, DNA-Binding Proteins metabolism, Gene Expression Regulation, Plant genetics, Gene Ontology, Histone Deacetylases genetics, Hypocotyl genetics, Hypocotyl growth & development, Mutation, Phenotype, Plants, Genetically Modified, Stress, Physiological genetics, Temperature, Arabidopsis genetics, Arabidopsis growth & development, Arabidopsis Proteins metabolism, Chromatin Assembly and Disassembly genetics, Epigenesis, Genetic, Histone Deacetylases metabolism, Transcriptome genetics
- Abstract
Elevated ambient temperatures affect plant growth and substantially impact biomass and crop yield. Recent results have indicated that chromatin remodelling is critical in plant thermal responses but how histone modification dynamics affects plant thermal response has not been clearly demonstarted. Here we show that Arabidopsis histone deacetylase genes HDA9, HDA15 and HDA19 play distinct roles in plant response to elevated ambient temperature. hda9 and hda19 mutants showed a warm-temperature-insensitive phenotype at 27°C, whereas hda15 plants displayed a constitutive warm-temperature-induced phenotype at 20°C and an enhanced thermal response at 27°C. The hda19 mutation led to upregulation of genes mostly related to stress response at both 20 and 27°C. The hda15 mutation resulted in upregulation of many warm temperature-responsive as well as metabolic genes at 20 and 27°C, while hda9 led to differential expression of a large number of genes at 20°C and impaired induction of warm-temperature-responsive genes at 27°C. HDA15 is associated with thermosensory mark genes at 20°C and that the association is decreased after shifting to 27°C, indicating that HDA15 is a direct repressor of plant thermal-responsive genes at normal temperature. In addition, as hda9, the hda15 mutation also led to upregulation of many metabolic genes and accumulation of primary metabolites. Furthermore, we show that HDA15 interacts with the transcription factor HFR1 (long Hypocotyl in Far Red1) to cooperatively repress warm-temperature response. Our study demonstrates that the histone deacetylases target to different sets of genes and play distinct roles in plant response to elevated ambient temperature., (© 2019 The Authors The Plant Journal © 2019 John Wiley & Sons Ltd.) more...
- Published
- 2019
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38. How could histone deacetylase activators be useful leads in the search for new therapeutics?
- Author
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Bourguet E and Naassila M
- Subjects
- Animals, Humans, Drug Discovery, Enzyme Activators pharmacology, Histone Deacetylase Inhibitors pharmacology, Histone Deacetylases metabolism
- Published
- 2019
- Full Text
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39. Redox Regulation of Monodehydroascorbate Reductase by Thioredoxin y in Plastids Revealed in the Context of Water Stress.
- Author
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Vanacker H, Guichard M, Bohrer AS, and Issakidis-Bourguet E
- Abstract
Thioredoxins (TRXs) are key players within the complex response network of plants to environmental constraints. Here, the physiological implication of the plastidial y-type TRXs in Arabidopsis drought tolerance was examined. We previously showed that TRXs y1 and y2 have antioxidant functions, and here, the corresponding single and double mutant plants were studied in the context of water deprivation. TRX y mutant plants showed reduced stress tolerance in comparison with wild-type (WT) plants that correlated with an increase in their global protein oxidation levels. Furthermore, at the level of the main antioxidant metabolites, while glutathione pool size and redox state were similarly affected by drought stress in WT and trxy1y2 plants, ascorbate (AsA) became more quickly and strongly oxidized in mutant leaves. Monodehydroascorbate (MDA) is the primary product of AsA oxidation and NAD(P)H-MDA reductase (MDHAR) ensures its reduction. We found that the extractable leaf NADPH-dependent MDHAR activity was strongly activated by TRX y2. Moreover, activity of recombinant plastid Arabidopsis MDHAR isoform (MDHAR6) was specifically increased by reduced TRX y, and not by other plastidial TRXs. Overall, these results reveal a new function for y-type TRXs and highlight their role as major antioxidants in plastids and their importance in plant stress tolerance. more...
- Published
- 2018
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40. Unexpected effect of cyclodepsipeptides bearing a sulfonylhydrazide moiety towards histone deacetylase activity.
- Author
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Létévé M, Gonzalez C, Moroy G, Martinez A, Jeanblanc J, Legastelois R, Naassila M, Sapi J, and Bourguet E
- Subjects
- Depsipeptides chemical synthesis, Drug Design, Histone Deacetylase 1 antagonists & inhibitors, Histone Deacetylase 1 chemistry, Histone Deacetylase 6 antagonists & inhibitors, Histone Deacetylase 6 chemistry, Histone Deacetylase Inhibitors chemical synthesis, Histone Deacetylases chemistry, Humans, Hydrazines chemical synthesis, Molecular Docking Simulation, Depsipeptides chemistry, Histone Deacetylase Inhibitors chemistry, Hydrazines chemistry
- Published
- 2018
- Full Text
- View/download PDF
41. Interest of new alkylsulfonylhydrazide-type compound in the treatment of alcohol use disorders.
- Author
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Jeanblanc J, Bourguet E, Sketriené D, Gonzalez C, Moroy G, Legastelois R, Létévé M, Trussardi-Régnier A, and Naassila M
- Subjects
- Alcoholism enzymology, Alcoholism psychology, Animals, Histone Deacetylase 1 chemistry, Histone Deacetylase 1 metabolism, Histone Deacetylase Inhibitors chemistry, Histone Deacetylase Inhibitors pharmacology, Male, Molecular Docking Simulation methods, Motivation drug effects, Motivation physiology, Rats, Rats, Long-Evans, Self Administration, Sulfatases chemistry, Sulfatases pharmacology, Sulfatases therapeutic use, Treatment Outcome, Alcoholism drug therapy, Ethanol administration & dosage, Histone Deacetylase 1 antagonists & inhibitors, Histone Deacetylase Inhibitors therapeutic use
- Abstract
Rationale: Recent preclinical research suggested that histone deacetylase inhibitors (HDACIs) and specifically class I HDAC selective inhibitors might be useful to treat alcohol use disorders (AUDs)., Objective: The objective of this study was to find a new inhibitor of the HDAC-1 isoenzyme and to test its efficacy in an animal model of AUDs., Methods: In the present study, we prepared new derivatives bearing sulfonylhydrazide-type zinc-binding group (ZBG) and evaluated these compounds in vitro on HDAC-1 isoenzyme. The most promising compound was tested on ethanol operant self-administration and relapse in rats., Results: We showed that the alkylsulfonylhydrazide-type compound (ASH) reduced by more than 55% the total amount of ethanol consumed after one intracerebroventricular microinjection, while no effect was observed on motivation of the animals to consume ethanol. In addition, one ASH injection in the central amygdala reduced relapse., Conclusions: Our study demonstrated that a new compound designed to target HDAC-1 is effective in reducing ethanol intake and relapse in rats and further confirm the interest of pursuing research to study the exact mechanism by which such inhibitor may be useful to treat AUDs. more...
- Published
- 2018
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42. Class I HDAC Inhibitors: Potential New Epigenetic Therapeutics for Alcohol Use Disorder (AUD).
- Author
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Bourguet E, Ozdarska K, Moroy G, Jeanblanc J, and Naassila M
- Subjects
- Animals, Epigenomics trends, Humans, Therapeutics methods, Therapeutics trends, Alcoholism drug therapy, Histone Deacetylase Inhibitors therapeutic use
- Abstract
Alcohol use disorder (AUD) represents a serious public health issue, and discovery of new therapies is a pressing necessity. Alcohol exposure has been widely demonstrated to modulate epigenetic mechanisms, such as histone acetylation/deacetylation balance, in part via histone deacetylase (HDAC) inhibition. Epigenetic factors have been suggested to play a key role in AUD. To date, 18 different mammalian HDAC isoforms have been identified, and these have been divided into four classes. Since recent studies have suggested that both epigenetic mechanisms underlying AUD and the efficacy of HDAC inhibitors (HDACIs) in different animal models of AUD may involve class I HDACs, we herein report the development of class I HDACIs, including information regarding their structure, potency, and selectivity. More effort is required to improve the selectivity, pharmacokinetics, and toxicity profiles of HDACIs to achieve a better understanding of their efficacy in reducing addictive behavior. more...
- Published
- 2018
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43. Invasive rats strengthen predation pressure on bird eggs in a South Pacific island rainforest.
- Author
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Duron Q, Bourguet E, De Meringo H, Millon A, and Vidal E
- Abstract
Invasive rats ( Rattus spp.) are known to have pervasive impacts on island birds, particularly on their nesting success. To conserve or restore bird populations, numerous invasive rat control or eradication projects are undertaken on islands worldwide. However, such projects represent a huge investment and the decision-making process requires proper assessment of rat impacts. Here, we assessed the influence of two sympatric invasive rats ( Rattus rattus and R. exulans ) on native bird eggs in a New Caledonian rainforest, using artificial bird-nest monitoring. A total of 178 artificial nests containing two eggs of three different sizes were placed either on the ground or 1.5 m high and monitored at the start of the birds' breeding season. Overall, 12.4% of the nests were depredated during the first 7 days. At site 1, where nests were monitored during 16 days, 41.8% of the nests were depredated. The main predator was the native crow Corvus moneduloides , responsible for 62.9% of the overall predation events. Rats were responsible for only 22.9% of the events, and ate only small and medium eggs at both heights. Our experiment suggests that in New Caledonia, predation pressure by rats strengthens overall bird-nest predation, adding to that by native predators. Experimental rat control operations may allow reduced predation pressure on nests as well as the recording of biodiversity responses after rat population reduction. more...
- Published
- 2017
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44. Cytosolic and Chloroplastic DHARs Cooperate in Oxidative Stress-Driven Activation of the Salicylic Acid Pathway.
- Author
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Rahantaniaina MS, Li S, Chatel-Innocenti G, Tuzet A, Issakidis-Bourguet E, Mhamdi A, and Noctor G
- Subjects
- Antioxidants metabolism, Arabidopsis metabolism, Ascorbic Acid metabolism, Cell Death, DNA, Bacterial genetics, Genetic Complementation Test, Glutathione metabolism, Green Fluorescent Proteins metabolism, Mutagenesis, Insertional genetics, Mutation genetics, Phenotype, Recombinant Fusion Proteins metabolism, Subcellular Fractions metabolism, Arabidopsis enzymology, Arabidopsis Proteins metabolism, Chloroplasts enzymology, Cytosol enzymology, Oxidative Stress, Oxidoreductases metabolism, Salicylic Acid metabolism
- Abstract
The complexity of plant antioxidative systems gives rise to many unresolved questions. One relates to the functional importance of dehydroascorbate reductases (DHARs) in interactions between ascorbate and glutathione. To investigate this issue, we produced a complete set of loss-of-function mutants for the three annotated Arabidopsis ( Arabidopsis thaliana ) DHARs. The combined loss of DHAR1 and DHAR3 expression decreased extractable activity to very low levels but had little effect on phenotype or ascorbate and glutathione pools in standard conditions. An analysis of the subcellular localization of the DHARs in Arabidopsis lines stably transformed with GFP fusion proteins revealed that DHAR1 and DHAR2 are cytosolic while DHAR3 is chloroplastic, with no evidence for peroxisomal or mitochondrial localizations. When the mutations were introduced into an oxidative stress genetic background ( cat2 ), the dhar1 dhar2 combination decreased glutathione oxidation and inhibited cat2 -triggered induction of the salicylic acid pathway. These effects were reversed in cat2 dhar1 dhar2 dhar3 complemented with any of the three DHARs. The data suggest that (1) DHAR can be decreased to negligible levels without marked effects on ascorbate pools, (2) the cytosolic isoforms are particularly important in coupling intracellular hydrogen peroxide metabolism to glutathione oxidation, and (3) DHAR-dependent glutathione oxidation influences redox-driven salicylic acid accumulation., (© 2017 American Society of Plant Biologists. All Rights Reserved.) more...
- Published
- 2017
- Full Text
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45. Thioredoxins Play a Crucial Role in Dynamic Acclimation of Photosynthesis in Fluctuating Light.
- Author
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Thormählen I, Zupok A, Rescher J, Leger J, Weissenberger S, Groysman J, Orwat A, Chatel-Innocenti G, Issakidis-Bourguet E, Armbruster U, and Geigenberger P
- Subjects
- Arabidopsis genetics, Arabidopsis growth & development, Arabidopsis radiation effects, Arabidopsis Proteins genetics, Arabidopsis Proteins metabolism, Chlorophyll metabolism, Chloroplast Thioredoxins genetics, Chloroplast Thioredoxins metabolism, Light, Malate Dehydrogenase (NADP+) metabolism, Mutation, Oxidation-Reduction, Photosynthesis radiation effects, Thioredoxin-Disulfide Reductase genetics, Thioredoxin-Disulfide Reductase metabolism, Acclimatization, Arabidopsis physiology, Chloroplast Thioredoxins physiology, Photosynthesis physiology
- Abstract
Sunlight represents the energy source for photosynthesis and plant growth. When growing in the field, plant photosynthesis has to manage strong fluctuations in light intensities. Regulation based on the thioredoxin (Trx) system is believed to ensure light-responsive control of photosynthetic reactions in the chloroplast. However, direct evidence for a role of this system in regulating dynamic acclimation of photosynthesis in fluctuating conditions is largely lacking. In this report we show that the ferredoxin-dependent Trxs m1 and m2 as well as the NADPH-dependent NTRC are both indispensable for photosynthetic acclimation in fluctuating light intensities. Arabidopsis mutants with combined deficiency in Trxs m1 and m2 show wild-type growth and photosynthesis under constant light condition, while photosynthetic parameters are strongly modified in rapidly alternating high and low light. Two independent trxm1m2 mutants show lower photosynthetic efficiency in high light, but surprisingly significantly higher photosynthetic efficiency in low light. Our data suggest that a main target of Trx m1 and m2 is the NADP-malate dehydrogenase involved in export of excess reductive power from the chloroplast. The decreased photosynthetic efficiency in the high-light peaks may thus be explained by a reduced capacity of the trxm1m2 mutants in the rapid light activation of this enzyme. In the ntrc mutant, dynamic responses of non-photochemical quenching of excitation energy and plastoquinone reduction state both were strongly attenuated in fluctuating light intensities, leading to a massive decrease in PSII quantum efficiency and a specific decrease in plant growth under these conditions. This is likely due to the decreased ability of the ntrc mutant to control the stromal NADP(H) redox poise. Taken together, our results indicate that NTRC is indispensable in ensuring the full range of dynamic responses of photosynthesis to optimize photosynthesis and maintain growth in fluctuating light, while Trxs m1 and m2 are indispensable for full activation of photosynthesis in the high-light periods but negatively affect photosynthetic efficiency in the low-light periods of fluctuating light., (Copyright © 2017 The Author. Published by Elsevier Inc. All rights reserved.) more...
- Published
- 2017
- Full Text
- View/download PDF
46. [Epigenetic mechanisms and alcohol use disorders: a potential therapeutic target].
- Author
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Legastelois R, Jeanblanc J, Vilpoux C, Bourguet E, and Naassila M
- Subjects
- Alcohol Drinking genetics, Alcohol Drinking therapy, Animals, Epigenesis, Genetic drug effects, Histone Deacetylase Inhibitors therapeutic use, Histone Deacetylases physiology, Humans, Molecular Targeted Therapy methods, Alcoholism genetics, Alcoholism therapy, Epigenesis, Genetic physiology, Molecular Targeted Therapy trends
- Abstract
Alcohol use disorder is a devastating illness with a profound health impact, and its development is dependent on both genetic and environmental factors. This disease occurs over time and requires changes in brain gene expression. There is converging evidence suggesting that the epigenetic processes may play a role in the alcohol-induced gene regulations and behavior such as the intervention of DNA methylation and histone acetylation. Histone acetylation, like histone methylation, is a highly dynamic process regulated by two classes of enzymes: histone acetyltransferases and histone deacetylases (HDACs). To date, 18 human HDAC isoforms have been characterized, and based on their sequence homologies and cofactor dependencies, they have been phylogenetically categorized into 4 main classes: classes I, II (a and b), III, and IV. In the brain, expression of the different classes of HDACs varies between cell types and also in their subcellular localization (nucleus and/or cytosol). Furthermore, we recently showed that a single ethanol exposure inhibits HDAC activity and increases both H3 and H4 histone acetylation within the amygdala of rats. In the brain of alcoholic patients, ethanol has been shown to induce histone-related and DNA methylation epigenetic changes in several reward regions involved in reward processes such as hippocampus, prefrontal cortex, and amygdala. We recently demonstrated alteration of histone H3 acetylation levels in several brain regions from the reward circuit of rats made dependent to alcohol after chronic and intermittent exposure to ethanol vapor. In neuronal cell line culture, ethanol was shown to induce HDAC expression. In mouse and rat brain, numerous studies reported epigenetic alterations following ethanol exposure. We also demonstrated that both the expression of genes and the activity of enzymes involved in epigenetic mechanisms are changed after repeated administrations of ethanol in mice sensitized to the motor stimulant effect of ethanol (a model of drug-induced neuroplasticity). Numerous studies have shown that HDAC inhibitors are able to counter ethanol-induced behaviors and the ethanol-induced changes in the levels of HDAC and/or levels of acetylated HDAC. For example, trichostatin A (TSA) treatment caused the reversal of ethanol-induced tolerance, anxiety, and ethanol drinking by inhibiting HDAC activity, thereby increasing histone acetylation in the amygdala of rats. Another study demonstrated that TSA prevented the development of ethanol withdrawal induced anxiety in rats by rescuing deficits in histone acetylation induced by increased HDAC activity in the amygdala. We have demonstrated that treatment with the HDAC inhibitor sodium butyrate blocks both the development and the expression of ethanol-induced behavioral sensitization in mice. In this context, converging evidence indicates that HDAC inhibitors could be useful in counteracting ethanol-induced gene regulations via epigenetic mechanisms, that is, HDAC inhibitors could affect different acetylation sites and may also alter the expression of different genes that could in turn counteract the effect of ethanol. Recent work in rodents has shown that systemic administration of pan HDAC class I and II inhibitors, TSA and N-hydroxy-N-phenyl-octanediamide [SuberoylAnilide Hydroxamic Acid] (SAHA), and of the more selective inhibitor (mainly HDAC1 and HDAC9) MS-275, decrease binge-like alcohol drinking in mice. SAHA selectively reduced ethanol operant self-administration and seeking in rats. Our previous study revealed that MS-275 strongly decreased operant ethanol self-administration in alcohol-dependent rats when administered 30 minutes before the session at the second day of injection. We also demonstrated that intra-cerebro-ventricular infusion of MS-275 increases acetylation of Histone 4 within the nucleus accumbens and the dorsolateral striatum, associated to a decrease in ethanol self-administration by about 75%. MS-275 also diminished both the motivation to consume ethanol (25% decrease), relapse (by about 50%) and postponed reacquisition after abstinence. Both literature and several of our studies strongly support the potential therapeutic interest of targeting epigenetic mechanisms in excessive alcohol drinking and strengthen theinterest of focusing on specific isoforms of histone deacetylases., (© Société de Biologie, 2017.) more...
- Published
- 2017
- Full Text
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47. Perspectives on the interactions between metabolism, redox, and epigenetics in plants.
- Author
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Shen Y, Issakidis-Bourguet E, and Zhou DX
- Subjects
- Gene Expression Regulation, Plant, Plant Development genetics, Plants genetics, Epigenesis, Genetic, Oxidation-Reduction, Plants metabolism
- Abstract
Epigenetic modifications of chromatin usually involve consumption of key metabolites and redox-active molecules. Primary metabolic flux and cellular redox states control the activity of enzymes involved in chromatin modifications, such as DNA methylation, histone acetylation, and histone methylation, which in turn regulate gene expression and/or enzymatic activity of specific metabolic and redox pathways. Thus, coordination of metabolism and epigenetic regulation of gene expression is critical to control growth and development in response to the cellular environment. Much has been learned from animal and yeast cells with regard to the interplay between metabolism and epigenetic regulation, and now the metabolic control of epigenetic pathways in plants is an increasing area of study. Epigenetic mechanisms are largely similar between plant and mammalian cells, but plants display very important differences in both metabolism and metabolic/redox signaling pathways. In this review, we summarize recent developments in the field and discuss perspectives of studying interactions between plant epigenetic and metabolism/redox systems, which are essential for plant adaptation to environmental conditions., (© The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.) more...
- Published
- 2016
- Full Text
- View/download PDF
48. Design, Synthesis, and Use of MMP-2 Inhibitor-Conjugated Quantum Dots in Functional Biochemical Assays.
- Author
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Bourguet E, Brazhnik K, Sukhanova A, Moroy G, Brassart-Pasco S, Martin AP, Villena I, Bellon G, Sapi J, and Nabiev I
- Subjects
- Drug Design, Matrix Metalloproteinase 2 drug effects, Protease Inhibitors chemistry, Protease Inhibitors pharmacology, Quantum Dots
- Abstract
The development of chemically designed matrix metalloprotease (MMP) inhibitors has advanced the understanding of the roles of MMPs in different diseases. Most MMP probes designed are fluorogenic substrates, often suffering from photo- and chemical instability and providing a fluorescence signal of moderate intensity, which is difficult to detect and analyze when dealing with crude biological samples. Here, an inhibitor that inhibits MMP-2 more selectively than Galardin has been synthesized and used for enzyme labeling and detection of the MMP-2 activity. A complete MMP-2 recognition complex consisting of a biotinylated MMP inhibitor tagged with the streptavidin-quantum dot (QD) conjugate has been prepared. This recognition complex, which is characterized by a narrow fluorescence emission spectrum, long fluorescence lifetime, and negligible photobleaching, has been demonstrated to specifically detect MMP-2 in in vitro sandwich-type biochemical assays with sensitivities orders of magnitude higher than those of the existing gold standards employing organic dyes. The approach developed can be used for specific in vitro visualization and testing of MMP-2 in cells and tissues with sensitivities significantly exceeding those of the best existing fluorogenic techniques. more...
- Published
- 2016
- Full Text
- View/download PDF
49. Putative role of the malate valve enzyme NADP-malate dehydrogenase in H2O2 signalling in Arabidopsis.
- Author
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Heyno E, Innocenti G, Lemaire SD, Issakidis-Bourguet E, and Krieger-Liszkay A
- Subjects
- Arabidopsis genetics, Catalase metabolism, Chloroplasts metabolism, DNA Primers genetics, Electron Spin Resonance Spectroscopy, Electrophoresis, Polyacrylamide Gel, Fluorescence, Immunoblotting, Malate Dehydrogenase (NADP+) deficiency, Models, Biological, Plant Extracts analysis, Plant Leaves chemistry, Reactive Oxygen Species metabolism, Arabidopsis physiology, Chloroplasts physiology, Hydrogen Peroxide metabolism, Malate Dehydrogenase (NADP+) metabolism, Photosynthesis physiology, Signal Transduction physiology, Thioredoxins metabolism
- Abstract
In photosynthetic organisms, sudden changes in light intensity perturb the photosynthetic electron flow and lead to an increased production of reactive oxygen species. At the same time, thioredoxins can sense the redox state of the chloroplast. According to our hypothesis, thioredoxins and related thiol reactive molecules downregulate the activity of H2O2-detoxifying enzymes, and thereby allow a transient oxidative burst that triggers the expression of H2O2 responsive genes. It has been shown recently that upon light stress, catalase activity was reversibly inhibited in Chlamydomonas reinhardtii in correlation with a transient increase in the level of H2O2. Here, it is shown that Arabidopsis thaliana mutants lacking the NADP-malate dehydrogenase have lost the reversible inactivation of catalase activity and the increase in H2O2 levels when exposed to high light. The mutants were slightly affected in growth and accumulated higher levels of NADPH in the chloroplast than the wild-type. We propose that the malate valve plays an essential role in the regulation of catalase activity and the accumulation of a H2O2 signal by transmitting the redox state of the chloroplast to other cell compartments. more...
- Published
- 2014
- Full Text
- View/download PDF
50. Redox regulation of chloroplastic G6PDH activity by thioredoxin occurs through structural changes modifying substrate accessibility and cofactor binding.
- Author
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Née G, Aumont-Nicaise M, Zaffagnini M, Nessler S, Valerio-Lepiniec M, and Issakidis-Bourguet E
- Subjects
- Arabidopsis enzymology, Arabidopsis genetics, Arabidopsis ultrastructure, Catalytic Domain, Chloroplasts drug effects, Disulfides chemistry, Disulfides metabolism, Enzyme Stability genetics, Glucose-6-Phosphate chemistry, Glucosephosphate Dehydrogenase genetics, Models, Molecular, Mutagenesis, Site-Directed, Oxidation-Reduction drug effects, Protein Binding, Protein Conformation drug effects, Chloroplasts enzymology, Coenzymes metabolism, Glucose-6-Phosphate metabolism, Glucosephosphate Dehydrogenase chemistry, Glucosephosphate Dehydrogenase metabolism, Thioredoxins pharmacology
- Abstract
In chloroplasts, redox regulation of enzyme activities by TRXs (thioredoxins) allows the co-ordination of light/dark metabolisms such as the reductive (so-called Calvin-Benson) pathway and the OPPP (oxidative pentose phosphate pathway). Although the molecular mechanisms underlying the redox regulation of several TRX-regulated enzymes have been investigated in detail, only partial information was available for plastidial G6PDH (glucose-6-phosphate dehydrogenase) catalysing the first and rate-limiting step of the OPPP. In the present study, we investigated changes in catalytic and structural properties undergone by G6PDH1 from Arabidopsis thaliana upon treatment with TRX f1, the most efficient regulator of the enzyme that did not show a stable interaction with its target. We found that the formation of the regulatory disulfide bridge that leads to activation of the enzyme allows better substrate accessibility to the active site and strongly modifies the cofactor-binding properties. Structural modelling and data from biochemical and biophysical studies of site-directed mutant proteins support a mechanism in which the positioning/function of the highly conserved Arg(131) in the cofactor-binding site can be directly influenced by the redox state of the adjacent regulatory disulfide bridge. These findings constitute another example of modifications to catalytic properties of a chloroplastic enzyme upon redox regulation, but by a mechanism unique to G6PDH. more...
- Published
- 2014
- Full Text
- View/download PDF
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