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Michel Havaux - One of the best experts on this subject based on the ideXlab platform.
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Plastoquinone homoeostasis by Arabidopsis proton gradient regulation 6 is essential for photosynthetic efficiency
Communications Biology, 2019Co-Authors: Thibaut Pralon, Brigitte Ksas, Michel Havaux, Gaetan Glauser, Giovanni Finazzi, Venkatasalam Shanmugabalaji, Paolo Longoni, Joy Collombat, Saskia Desmeules, Felix KesslerAbstract:Photosynthesis produces organic carbon via a light-driven electron flow from H$_2$O to CO$_2$ that passes through a pool of Plastoquinone molecules. These molecules are either present in the photosynthetic thylakoid membranes, participating in photochemistry (photoactive pool), or stored (non-photoactive pool) in thylakoid-attached lipid droplets, the plastoglobules. The photoactive pool acts also as a signal of photosynthetic activity allowing the adaptation to changes in light condition. Here we show that, in $Arabidopsis\ thaliana$, proton gradient regulation 6 (PGR6), a predicted atypical kinase located at plastoglobules, is required for Plastoquinone homoeostasis, i.e. to maintain the photoactive Plastoquinone pool. In a $pgr$6 mutant, the photoactive pool is depleted and becomes limiting under high light, affecting short-term acclimation and photosynthetic efficiency. In the long term, $pgr$6 seedlings fail to adapt to high light and develop a conditional variegated leaf phenotype. Therefore, PGR6 activity, by regulating Plastoquinone homoeostasis, is required to cope with high light.
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plant tolerance to excess light energy and photooxidative damage relies on Plastoquinone biosynthesis
Scientific Reports, 2015Co-Authors: Brigitte Ksas, Noelle Becuwe, Anne Chevalier, Michel HavauxAbstract:Plastoquinone-9 is known as a photosynthetic electron carrier to which has also been attributed a role in the regulation of gene expression and enzyme activities via its redox state. Here, we show that it acts also as an antioxidant in plant leaves, playing a central photoprotective role. When Arabidopsis plants were suddenly exposed to excess light energy, a rapid consumption of Plastoquinone-9 occurred, followed by a progressive increase in concentration during the acclimation phase. By overexpressing the Plastoquinone-9 biosynthesis gene SPS1 (SOLANESYL DIPHOSPHATE SYNTHASE 1) in Arabidopsis, we succeeded in generating plants that specifically accumulate Plastoquinone-9 and its derivative plastochromanol-8. The SPS1-overexpressing lines were much more resistant to photooxidative stress than the wild type, showing marked decreases in leaf bleaching, lipid peroxidation and PSII photoinhibition under excess light. Comparison of the SPS1 overexpressors with other prenyl quinone mutants indicated that the enhanced phototolerance of the former plants is directly related to their increased capacities for Plastoquinone-9 biosynthesis.
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chloroplast lipid droplet type ii nad p h quinone oxidoreductase is essential for prenylquinone metabolism and vitamin k1 accumulation
Proceedings of the National Academy of Sciences of the United States of America, 2011Co-Authors: Lucia Eugeni Piller, Dominique Rumeau, Brigitte Ksas, Celine Besagni, Claire Brehelin, Gaetan Glauser, Felix Kessler, Michel HavauxAbstract:Lipid droplets are ubiquitous cellular structures in eukaryotes and are required for lipid metabolism. Little is currently known about plant lipid droplets other than oil bodies. Here, we define dual roles for chloroplast lipid droplets (plastoglobules) in energy and prenylquinone metabolism. The prenylquinones—Plastoquinone, plastochromanol-8, phylloquinone (vitamin K1), and tocopherol (vitamin E)—are partly stored in plastoglobules. This work shows that NAD(P)H dehydrogenase C1 (NDC1) (At5g08740), a type II NAD(P)H quinone oxidoreductase, associates with plastoglobules. NDC1 reduces a Plastoquinone analog in vitro and affects the overall redox state of the total Plastoquinone pool in vivo by reducing the Plastoquinone reservoir of plastoglobules. Finally, NDC1 is required for normal plastochromanol-8 accumulation and is essential for vitamin K1 production.
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Chloroplast lipid droplet type II NAD(P)H quinone oxidoreductase is essential for prenylquinone metabolism and vitamin K1 accumulation
Proceedings of the National Academy of Sciences of the United States of America, 2011Co-Authors: Lucia Eugeni Piller, Dominique Rumeau, Brigitte Ksas, Celine Besagni, Claire Brehelin, Gaetan Glauser, Felix Kessler, Michel HavauxAbstract:Lipid droplets are ubiquitous cellular structures in eukaryotes and are required for lipid metabolism. Little is currently known about plant lipid droplets other than oil bodies. Here, we define dual roles for chloroplast lipid droplets (plastoglobules) in energy and prenylquinone metabolism. The prenylquinones-Plastoquinone, plastochromanol-8, phylloquinone (vitamin K 1), and tocopherol (vitamin E)-are partly stored in plastoglobules. This work shows that NAD(P)H dehydrogenase C1 (NDC1) (At5g08740), a type II NAD(P)H quinone oxidoreductase, associates with plastoglobules. NDC1 reduces a Plastoquinone analog in vitro and affects the overall redox state of the total Plastoquinone pool in vivo by reducing the Plastoquinone reservoir of plastoglobules. Finally, NDC1 is required for normal plastochromanol-8 accumulation and is essential for vitamin K 1 production. lipidomics | alternative electron flow | high light
Jerzy Kruk - One of the best experts on this subject based on the ideXlab platform.
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Cyanobacteria use both p-hydroxybenozate and homogentisate as a precursor of Plastoquinone head group
Acta Physiologiae Plantarum, 2016Co-Authors: Beatrycze Nowicka, Jerzy KrukAbstract:Until recently it was believed that cyanobacterial pathway of Plastoquinone biosynthesis is analogical to that of higher plants. In plants, homogentisate is a precursor of the hydrophilic head group of Plastoquinone. Recent experiments on Synechocystis sp. PCC 6803 have shown that this organism takes advantage of another pathway that resembles ubiquinone biosynthetic pathway of α-, β- and γ-proteobacteria. In the present work, we have analysed the content of Plastoquinone, tocopherol and tocopherolquinone in six strains of cyanobacteria and compared the obtained results with search for genes of homologues of enzymes participating in tocopherol and ubiquinone biosynthesis. We have shown that inhibition of homogentisate synthesis lowers tocopherol content but does not affect Plastoquinone synthesis in Synechococcus sp. PCC 7002. Inhibitors of p-hydroxybenzoate and homogentisate prenyltransferases selectively influenced Plastoquinone and tocopherol biosynthesis in Synechocystis sp. PCC 6803. Radiolabelled 14C-p-hydroxybenzoate was incorporated into Plastoquinone by three cyanobacteria species investigated. Although, when 14C-homogentisate was added to growth medium, the labelled Plastoquinone was found in extracts of the cyanobacteria. Synechocystis sp. PCC 6803 grown in the presence of 14C-homogentisate showed also small amounts of the labelled tyrosine, suggesting that cyanobacteria are able to incorporate exogenously added homogentisate into shikimate pathway.
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Hydroxy-plastochromanol and Plastoquinone-C as singlet oxygen products during photo-oxidative stress in Arabidopsis.
Plant Cell & Environment, 2014Co-Authors: Renata Szymańska, Beatrycze Nowicka, Jerzy KrukAbstract:In the present study, we have shown that hydroxy-plastochromanol and Plastoquinone-C, the hydroxy derivatives of plastochromanol and Plastoquinone-9, respectively, are specifically formed from the parent compounds upon action of singlet oxygen and can be regarded as stable, specific, natural products of singlet oxygen action during photo-oxidative stress in vivo. The presented data indicate that Plastoquinone-C formation dominates mainly during relatively short periods of high light stress where efficient production of singlet oxygen takes place, whereas hydroxy-plastochromanol is rather formed under conditions of long-term, less pronounced generation of singlet oxygen. An interesting observation was that hydroxy-plastochromanol is formed even at very low light conditions (5-10 μmol photons m(-2) s(-1)), indicating that singlet oxygen is generated not only during high light stress but also its formation by photosystem II is inseparably connected with the functioning of this photosystem even at the lowest light intensities.
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Singlet oxygen and non-photochemical quenching contribute to oxidation of the Plastoquinone-pool under high light stress in Arabidopsis.
Biochimica et Biophysica Acta (BBA) - Bioenergetics, 2012Co-Authors: Jerzy Kruk, Renata SzymańskaAbstract:The redox state of Plastoquinone-pool in chloroplasts is crucial for driving many responses to variable environment, from short-term effects to those at the gene expression level. In the present studies, we showed for the first time that the Plastoquinone-pool undergoes relatively fast oxidation during high light stress of low light-grown Arabidopsis plants. This oxidation was not caused by photoinhibition of photosystem II, but mainly by singlet oxygen generated in photosystem II and non-photochemical quenching in light harvesting complex antenna of the photosystem, as revealed in experiments with a singlet oxygen scavenger and with Arabidopsis npq4 mutant. The latter mechanism suppresses the influx of electrons to the Plastoquinone-pool preventing its excessive reduction. The obtained results are of crucial importance in light of the function of the redox state of the Plastoquinone-pool in triggering many high light-stimulated physiological responses of plants.
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plastoquinol as a singlet oxygen scavenger in photosystem ii
Biochimica et Biophysica Acta, 2008Co-Authors: Jerzy Kruk, Achim TrebstAbstract:We have found that in control Chlamydomonas reinhardtii cells, under high-light stress, the level of reduced Plastoquinone considerably increases while in the presence of pyrazolate, an inhibitor of Plastoquinone and tocopherol biosynthesis, the content of reduced Plastoquinone quickly decreases, similarly to α-tocopherol. Photodegradation of both prenyllipids was partially reversed by diphenylamine, a singlet oxygen scavenger. It was concluded that under high-light stress plastoquinol, as well as α-tocopherol is degraded as a result of a scavenging reaction of singlet oxygen generated in photosystem II. The lack of photodegradation of α-tocopherol and of the reduced Plastoquinone in the absence of the inhibitor is due to a fast turnover of both prenyllipids, i.e., their degradation is compensated by fast biosynthesis. We have also found that the level of α-tocopherol quinone, an oxidation product of α-tocopherol, increases as the α-tocopherol is consumed. The same correlation was also observed for γ-tocopherol and its quinone form.
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Plastoquinones are effectively reduced by ferredoxin nadp oxidoreductase in the presence of sodium cholate micelles significance for cyclic electron transport and chlororespiration
Phytochemistry, 2003Co-Authors: Monika Bojko, Jerzy Kruk, Stanislaw WieckowskiAbstract:The effect of sodium cholate and other detergents (Triton X-100, sodium dodecyl sulphate, octyl glucoside, myristyltrimethylammonium bromide) on the reduction of Plastoquinones (PQ) with a different length of the side-chain by spinach ferredoxin:NADP(+) oxidoreductase (FNR) in the presence of NADPH has been studied. Both NADPH oxidation and oxygen uptake due to plastosemiquinone autoxidation were highly stimulated only in the presence of sodium cholate among the used detergents. Sodium cholate at the concentration of 20 mM was found to be the most effective on both PQ-4 and PQ-9-mediated oxygen uptake. The FNR-dependent reduction of Plastoquinones incorporated into sodium cholate micelles was stimulated by spinach ferredoxin but inhibited by Mg(2+) ions. It was concluded that the structure of sodium cholate micelles facilitates contact of Plastoquinone molecules with the enzyme and creates favourable conditions for the reaction similar to those found in thylakoid membranes for PQ-9 reduction. The obtained results were discussed in terms of the function of FNR as a ferredoxin:Plastoquinone reductase both in cyclic electron transport and chlororespiration.
Dominique Rumeau - One of the best experts on this subject based on the ideXlab platform.
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Chloroplast lipid droplet type II NAD(P)H quinone oxidoreductase is essential for prenylquinone metabolism and vitamin K1 accumulation
Proceedings of the National Academy of Sciences of the United States of America, 2011Co-Authors: Lucia Eugeni Piller, Dominique Rumeau, Brigitte Ksas, Celine Besagni, Claire Brehelin, Gaetan Glauser, Felix Kessler, Michel HavauxAbstract:Lipid droplets are ubiquitous cellular structures in eukaryotes and are required for lipid metabolism. Little is currently known about plant lipid droplets other than oil bodies. Here, we define dual roles for chloroplast lipid droplets (plastoglobules) in energy and prenylquinone metabolism. The prenylquinones-Plastoquinone, plastochromanol-8, phylloquinone (vitamin K 1), and tocopherol (vitamin E)-are partly stored in plastoglobules. This work shows that NAD(P)H dehydrogenase C1 (NDC1) (At5g08740), a type II NAD(P)H quinone oxidoreductase, associates with plastoglobules. NDC1 reduces a Plastoquinone analog in vitro and affects the overall redox state of the total Plastoquinone pool in vivo by reducing the Plastoquinone reservoir of plastoglobules. Finally, NDC1 is required for normal plastochromanol-8 accumulation and is essential for vitamin K 1 production. lipidomics | alternative electron flow | high light
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chloroplast lipid droplet type ii nad p h quinone oxidoreductase is essential for prenylquinone metabolism and vitamin k1 accumulation
Proceedings of the National Academy of Sciences of the United States of America, 2011Co-Authors: Lucia Eugeni Piller, Dominique Rumeau, Brigitte Ksas, Celine Besagni, Claire Brehelin, Gaetan Glauser, Felix Kessler, Michel HavauxAbstract:Lipid droplets are ubiquitous cellular structures in eukaryotes and are required for lipid metabolism. Little is currently known about plant lipid droplets other than oil bodies. Here, we define dual roles for chloroplast lipid droplets (plastoglobules) in energy and prenylquinone metabolism. The prenylquinones—Plastoquinone, plastochromanol-8, phylloquinone (vitamin K1), and tocopherol (vitamin E)—are partly stored in plastoglobules. This work shows that NAD(P)H dehydrogenase C1 (NDC1) (At5g08740), a type II NAD(P)H quinone oxidoreductase, associates with plastoglobules. NDC1 reduces a Plastoquinone analog in vitro and affects the overall redox state of the total Plastoquinone pool in vivo by reducing the Plastoquinone reservoir of plastoglobules. Finally, NDC1 is required for normal plastochromanol-8 accumulation and is essential for vitamin K1 production.
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chlororespiration and cyclic electron flow around psi during photosynthesis and plant stress response
Plant Cell and Environment, 2007Co-Authors: Dominique Rumeau, Gilles Peltier, Laurent CournacAbstract:Besides major photosynthetic complexes of oxygenic photosynthesis, new electron carriers have been identified in thylakoid membranes of higher plant chloroplasts. These minor components, located in the stroma lamellae, include a plastidial NAD(P)H dehydrogenase (NDH) complex and a plastid terminal Plastoquinone oxidase (PTOX). The NDH complex, by reducing Plastoquinones (PQs), participates in one of the two electron transfer pathways operating around photosystem I (PSI), the other likely involving a still uncharacterized ferredoxin-Plastoquinone reductase (FQR) and the newly discovered PGR5. The existence of a complex network of mechanisms regulating expression and activity of the NDH complex, and the presence of higher amounts of NDH complex and PTOX in response to environmental stress conditions the phenotype of mutants, indicate that these components likely play a role in the acclimation of photosynthesis to changing environmental conditions. Based on recently published data, we propose that the NDH-dependent cyclic pathway around PSI participates to the ATP supply in conditions of high ATP demand (such as high temperature or water limitation) and together with PTOX regulates cyclic electron transfer activity by tuning the redox state of intersystem electron carriers. In response to severe stress conditions, PTOX associated to the NDH and/or the PGR5 pathway may also limit electron pressure on PSI acceptor and prevent PSI photoinhibition.
Lucia Eugeni Piller - One of the best experts on this subject based on the ideXlab platform.
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chloroplast lipid droplet type ii nad p h quinone oxidoreductase is essential for prenylquinone metabolism and vitamin k1 accumulation
Proceedings of the National Academy of Sciences of the United States of America, 2011Co-Authors: Lucia Eugeni Piller, Dominique Rumeau, Brigitte Ksas, Celine Besagni, Claire Brehelin, Gaetan Glauser, Felix Kessler, Michel HavauxAbstract:Lipid droplets are ubiquitous cellular structures in eukaryotes and are required for lipid metabolism. Little is currently known about plant lipid droplets other than oil bodies. Here, we define dual roles for chloroplast lipid droplets (plastoglobules) in energy and prenylquinone metabolism. The prenylquinones—Plastoquinone, plastochromanol-8, phylloquinone (vitamin K1), and tocopherol (vitamin E)—are partly stored in plastoglobules. This work shows that NAD(P)H dehydrogenase C1 (NDC1) (At5g08740), a type II NAD(P)H quinone oxidoreductase, associates with plastoglobules. NDC1 reduces a Plastoquinone analog in vitro and affects the overall redox state of the total Plastoquinone pool in vivo by reducing the Plastoquinone reservoir of plastoglobules. Finally, NDC1 is required for normal plastochromanol-8 accumulation and is essential for vitamin K1 production.
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Chloroplast lipid droplet type II NAD(P)H quinone oxidoreductase is essential for prenylquinone metabolism and vitamin K1 accumulation
Proceedings of the National Academy of Sciences of the United States of America, 2011Co-Authors: Lucia Eugeni Piller, Dominique Rumeau, Brigitte Ksas, Celine Besagni, Claire Brehelin, Gaetan Glauser, Felix Kessler, Michel HavauxAbstract:Lipid droplets are ubiquitous cellular structures in eukaryotes and are required for lipid metabolism. Little is currently known about plant lipid droplets other than oil bodies. Here, we define dual roles for chloroplast lipid droplets (plastoglobules) in energy and prenylquinone metabolism. The prenylquinones-Plastoquinone, plastochromanol-8, phylloquinone (vitamin K 1), and tocopherol (vitamin E)-are partly stored in plastoglobules. This work shows that NAD(P)H dehydrogenase C1 (NDC1) (At5g08740), a type II NAD(P)H quinone oxidoreductase, associates with plastoglobules. NDC1 reduces a Plastoquinone analog in vitro and affects the overall redox state of the total Plastoquinone pool in vivo by reducing the Plastoquinone reservoir of plastoglobules. Finally, NDC1 is required for normal plastochromanol-8 accumulation and is essential for vitamin K 1 production. lipidomics | alternative electron flow | high light
Brigitte Ksas - One of the best experts on this subject based on the ideXlab platform.
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Plastoquinone homoeostasis by Arabidopsis proton gradient regulation 6 is essential for photosynthetic efficiency
Communications Biology, 2019Co-Authors: Thibaut Pralon, Brigitte Ksas, Michel Havaux, Gaetan Glauser, Giovanni Finazzi, Venkatasalam Shanmugabalaji, Paolo Longoni, Joy Collombat, Saskia Desmeules, Felix KesslerAbstract:Photosynthesis produces organic carbon via a light-driven electron flow from H$_2$O to CO$_2$ that passes through a pool of Plastoquinone molecules. These molecules are either present in the photosynthetic thylakoid membranes, participating in photochemistry (photoactive pool), or stored (non-photoactive pool) in thylakoid-attached lipid droplets, the plastoglobules. The photoactive pool acts also as a signal of photosynthetic activity allowing the adaptation to changes in light condition. Here we show that, in $Arabidopsis\ thaliana$, proton gradient regulation 6 (PGR6), a predicted atypical kinase located at plastoglobules, is required for Plastoquinone homoeostasis, i.e. to maintain the photoactive Plastoquinone pool. In a $pgr$6 mutant, the photoactive pool is depleted and becomes limiting under high light, affecting short-term acclimation and photosynthetic efficiency. In the long term, $pgr$6 seedlings fail to adapt to high light and develop a conditional variegated leaf phenotype. Therefore, PGR6 activity, by regulating Plastoquinone homoeostasis, is required to cope with high light.
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plant tolerance to excess light energy and photooxidative damage relies on Plastoquinone biosynthesis
Scientific Reports, 2015Co-Authors: Brigitte Ksas, Noelle Becuwe, Anne Chevalier, Michel HavauxAbstract:Plastoquinone-9 is known as a photosynthetic electron carrier to which has also been attributed a role in the regulation of gene expression and enzyme activities via its redox state. Here, we show that it acts also as an antioxidant in plant leaves, playing a central photoprotective role. When Arabidopsis plants were suddenly exposed to excess light energy, a rapid consumption of Plastoquinone-9 occurred, followed by a progressive increase in concentration during the acclimation phase. By overexpressing the Plastoquinone-9 biosynthesis gene SPS1 (SOLANESYL DIPHOSPHATE SYNTHASE 1) in Arabidopsis, we succeeded in generating plants that specifically accumulate Plastoquinone-9 and its derivative plastochromanol-8. The SPS1-overexpressing lines were much more resistant to photooxidative stress than the wild type, showing marked decreases in leaf bleaching, lipid peroxidation and PSII photoinhibition under excess light. Comparison of the SPS1 overexpressors with other prenyl quinone mutants indicated that the enhanced phototolerance of the former plants is directly related to their increased capacities for Plastoquinone-9 biosynthesis.
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chloroplast lipid droplet type ii nad p h quinone oxidoreductase is essential for prenylquinone metabolism and vitamin k1 accumulation
Proceedings of the National Academy of Sciences of the United States of America, 2011Co-Authors: Lucia Eugeni Piller, Dominique Rumeau, Brigitte Ksas, Celine Besagni, Claire Brehelin, Gaetan Glauser, Felix Kessler, Michel HavauxAbstract:Lipid droplets are ubiquitous cellular structures in eukaryotes and are required for lipid metabolism. Little is currently known about plant lipid droplets other than oil bodies. Here, we define dual roles for chloroplast lipid droplets (plastoglobules) in energy and prenylquinone metabolism. The prenylquinones—Plastoquinone, plastochromanol-8, phylloquinone (vitamin K1), and tocopherol (vitamin E)—are partly stored in plastoglobules. This work shows that NAD(P)H dehydrogenase C1 (NDC1) (At5g08740), a type II NAD(P)H quinone oxidoreductase, associates with plastoglobules. NDC1 reduces a Plastoquinone analog in vitro and affects the overall redox state of the total Plastoquinone pool in vivo by reducing the Plastoquinone reservoir of plastoglobules. Finally, NDC1 is required for normal plastochromanol-8 accumulation and is essential for vitamin K1 production.
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Chloroplast lipid droplet type II NAD(P)H quinone oxidoreductase is essential for prenylquinone metabolism and vitamin K1 accumulation
Proceedings of the National Academy of Sciences of the United States of America, 2011Co-Authors: Lucia Eugeni Piller, Dominique Rumeau, Brigitte Ksas, Celine Besagni, Claire Brehelin, Gaetan Glauser, Felix Kessler, Michel HavauxAbstract:Lipid droplets are ubiquitous cellular structures in eukaryotes and are required for lipid metabolism. Little is currently known about plant lipid droplets other than oil bodies. Here, we define dual roles for chloroplast lipid droplets (plastoglobules) in energy and prenylquinone metabolism. The prenylquinones-Plastoquinone, plastochromanol-8, phylloquinone (vitamin K 1), and tocopherol (vitamin E)-are partly stored in plastoglobules. This work shows that NAD(P)H dehydrogenase C1 (NDC1) (At5g08740), a type II NAD(P)H quinone oxidoreductase, associates with plastoglobules. NDC1 reduces a Plastoquinone analog in vitro and affects the overall redox state of the total Plastoquinone pool in vivo by reducing the Plastoquinone reservoir of plastoglobules. Finally, NDC1 is required for normal plastochromanol-8 accumulation and is essential for vitamin K 1 production. lipidomics | alternative electron flow | high light