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Bo Y, Wang S, Ma F, Yurevich Manyakhin A, Zhang G, Li X, Zhou C, Ge B, Yan X, Ruan R, Cheng P. The influence of spermidine on the build-up of fucoxanthin in Isochrysis sp. Acclimated to varying light intensities. BIORESOURCE TECHNOLOGY 2023; 387:129688. [PMID: 37595805 DOI: 10.1016/j.biortech.2023.129688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 08/12/2023] [Accepted: 08/14/2023] [Indexed: 08/20/2023]
Abstract
Spermidine is a type of important growth regulator, which involved in the biosynthesis of photosynthetic pigments, and has the function of promoting cell proliferation. In this study, Isochrysis sp. was selected as the research object to explore the effects of spermidine supplementation on the growth of algal cells and fucoxanthin synthesis under different light intensities. The results showed that the cell density (5.40 × 106 cells/mL) of algae were the highest at 11 days under the light intensity of 200 μmol·m-2·s-1 and spermidine content of 150 μM. The contents of diadinoxanthin (1.09 mg/g) and fucoxanthin (6.11 mg/g) were the highest when spermidine was added under low light intensity, and the growth of algal cells and fucoxanthin metabolism were the most significant. In the carotenoid synthesis pathway, PDS (phytoene desaturase) was up-regulated by 1.96 times and VDE (violaxanthin de-epoxidase) was down-regulated by 0.95 times, which may promote fucoxanthin accumulation.
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Affiliation(s)
- Yahui Bo
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Shanshan Wang
- The first affiliated hospital of Ningbo university, Ningbo, Zhejiang 315211, China
| | - Feifei Ma
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Artem Yurevich Manyakhin
- Far Eastern Branch, Russian Academy of Sciences, Federal Scientific Center of East Asian Terrestrial Biodiversity, 100-letiya Vladivostoka Prospect, 159, Vladivostok 690022, Russia
| | - Guilin Zhang
- Lianxi Ecological Environment Bureau of Jiujiang City, Jiujiang, Jiangxi 332005, China
| | - Xiaohui Li
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Chengxu Zhou
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Baosheng Ge
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao 266580, China
| | - Xiaojun Yan
- Key Laboratory of Marine Biotechnology of Zhejiang Province, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Roger Ruan
- Center for Biorefining, and Department of Bioproducts and Biosystems Engineering, University of Minnesota-Twin Cities, Saint Paul, MN 55108, USA
| | - Pengfei Cheng
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, Zhejiang 315211, China; Center for Biorefining, and Department of Bioproducts and Biosystems Engineering, University of Minnesota-Twin Cities, Saint Paul, MN 55108, USA.
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Navakoudis E, Kotzabasis K. Polyamines: Α bioenergetic smart switch for plant protection and development. JOURNAL OF PLANT PHYSIOLOGY 2022; 270:153618. [PMID: 35051689 DOI: 10.1016/j.jplph.2022.153618] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 01/09/2022] [Accepted: 01/10/2022] [Indexed: 05/27/2023]
Abstract
The present review highlights the bioenergetic role of polyamines in plant protection and development and proposes a universal model for describing polyamine-mediated stress responses. Any stress condition induces an excitation pressure on photosystem II by reforming the photosynthetic apparatus. To control this phenomenon, polyamines act directly on the molecular structure and function of the photosynthetic apparatus as well as on the components of the chemiosmotic proton-motive force (ΔpH/Δψ), thus regulating photochemical (qP) and non-photochemical quenching (NPQ) of energy. The review presents the mechanistic characteristics that underline the key role of polyamines in the structure, function, and bioenergetics of the photosynthetic apparatus upon light adaptation and/or under stress conditions. By following this mechanism, it is feasible to make stress-sensitive plants to be tolerant by simply altering their polyamine composition (especially the ratio of putrescine to spermine), either chemically or by light regulation.
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Affiliation(s)
- Eleni Navakoudis
- Department of Biology, University of Crete, Voutes University Campus, 70013, Heraklion, Greece; Department of Chemical Engineering, Cyprus University of Technology, 3603, Limassol, Cyprus
| | - Kiriakos Kotzabasis
- Department of Biology, University of Crete, Voutes University Campus, 70013, Heraklion, Greece.
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3
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Li L, Gu W, Li J, Li C, Xie T, Qu D, Meng Y, Li C, Wei S. Exogenously applied spermidine alleviates photosynthetic inhibition under drought stress in maize (Zea mays L.) seedlings associated with changes in endogenous polyamines and phytohormones. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2018; 129:35-55. [PMID: 29793181 DOI: 10.1016/j.plaphy.2018.05.017] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 05/09/2018] [Accepted: 05/10/2018] [Indexed: 05/21/2023]
Abstract
Drought stress (DS) is a major environmental factor limiting plant growth and crop productivity worldwide. It has been established that exogenous spermidine (Spd) stimulates plant tolerance to DS. The effects of exogenous Spd on plant growth, photosynthetic performance, and chloroplast ultrastructure as well as changes in endogenous polyamines (PAs) and phytohormones were investigate in DS-resistant (Xianyu 335) and DS-sensitive (Fenghe 1) maize seedlings under well-watered and DS treatments. Exogenous Spd alleviated the stress-induced reduction in growth, photosynthetic pigment content, photosynthesis rate (Pn) and photochemical quenching (qP) parameters, including the maximum photochemistry efficiency of photosystem II (PSII) (Fv/Fm), PSII operating efficiency (ФPSII), and qP coefficient. Exogenous Spd further enhanced stress-induced elevation in non-photochemical quenching (NPQ) and the de-epoxidation state of the xanthophyll cycle (DEPS). Microscopic analysis revealed that seedlings displayed a more ordered arrangement of chloroplast ultrastructure upon Spd application during DS. Exogenous Spd increased the endogenous PA concentrations in the stressed plants. Additionally, exogenous Spd increased indoleacetic acid (IAA), zeatin riboside (ZR) and gibberellin A3 (GA3) and decreased salicylic acid (SA) and jasmonate (JA) concentrations under DS. These results indicate that exogenous Spd can alleviate the growth inhibition and damage to the structure and function of the photosynthetic apparatus caused by DS and that this alleviation may be associated with changes in endogenous PAs and phytohormones. This study contributes to advances in the knowledge of Spd-induced drought tolerance.
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Affiliation(s)
- Lijie Li
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, China
| | - Wanrong Gu
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, China
| | - Jing Li
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, China
| | - Congfeng Li
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 10081, China
| | - Tenglong Xie
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, China
| | - Danyang Qu
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, China
| | - Yao Meng
- Heilongjiang Academy of Land Reclamation Sciences, Harbin, 150038, Heilongjiang, China
| | - Caifeng Li
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, China
| | - Shi Wei
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, China.
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Khan MV, Zakariya SM, Khan RH. Protein folding, misfolding and aggregation: A tale of constructive to destructive assembly. Int J Biol Macromol 2018; 112:217-229. [DOI: 10.1016/j.ijbiomac.2018.01.099] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 01/04/2018] [Accepted: 01/14/2018] [Indexed: 12/20/2022]
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Kaňa R, Govindjee. Role of Ions in the Regulation of Light-Harvesting. FRONTIERS IN PLANT SCIENCE 2016; 7:1849. [PMID: 28018387 PMCID: PMC5160696 DOI: 10.3389/fpls.2016.01849] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 11/23/2016] [Indexed: 03/03/2024]
Abstract
Regulation of photosynthetic light harvesting in the thylakoids is one of the major key factors affecting the efficiency of photosynthesis. Thylakoid membrane is negatively charged and influences both the structure and the function of the primarily photosynthetic reactions through its electrical double layer (EDL). Further, there is a heterogeneous organization of soluble ions (K+, Mg2+, Cl-) attached to the thylakoid membrane that, together with fixed charges (negatively charged amino acids, lipids), provides an electrical field. The EDL is affected by the valence of the ions and interferes with the regulation of "state transitions," protein interactions, and excitation energy "spillover" from Photosystem II to Photosystem I. These effects are reflected in changes in the intensity of chlorophyll a fluorescence, which is also a measure of photoprotective non-photochemical quenching (NPQ) of the excited state of chlorophyll a. A triggering of NPQ proceeds via lumen acidification that is coupled to the export of positive counter-ions (Mg2+, K+) to the stroma or/and negative ions (e.g., Cl-) into the lumen. The effect of protons and anions in the lumen and of the cations (Mg2+, K+) in the stroma are, thus, functionally tightly interconnected. In this review, we discuss the consequences of the model of EDL, proposed by Barber (1980b) Biochim Biophys Acta 594:253-308) in light of light-harvesting regulation. Further, we explain differences between electrostatic screening and neutralization, and we emphasize the opposite effect of monovalent (K+) and divalent (Mg2+) ions on light-harvesting and on "screening" of the negative charges on the thylakoid membrane; this effect needs to be incorporated in all future models of photosynthetic regulation by ion channels and transporters.
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Affiliation(s)
- Radek Kaňa
- Institute of Microbiology, Academy of Sciences of the CzechiaTřeboň, Czechia
- Faculty of Science, Institute of Chemistry and Biochemistry, University of South BohemiaČeské Budějovice, Czechia
| | - Govindjee
- Center of Biophysics and Quantitative Biology, Department of Biochemistry, Department of Plant Biology, University of Illinois at Urbana-ChampaignUrbana, IL, USA
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6
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Ioannidis NE, Malliarakis D, Torné JM, Santos M, Kotzabasis K. The Over-expression of the Plastidial Transglutaminase from Maize in Arabidopsis Increases the Activation Threshold of Photoprotection. FRONTIERS IN PLANT SCIENCE 2016; 7:635. [PMID: 27242838 PMCID: PMC4861818 DOI: 10.3389/fpls.2016.00635] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 04/25/2016] [Indexed: 05/09/2023]
Abstract
Plastidial transglutaminase is one of the most promising enzymes in chloroplast bioenergetics due to its link with polyamine pathways and the cross talk with signals such as Ca(2+) and GTP. Here, we show the effect of the increase of transglutaminase activity in Arabidopsis by using genetic transformation techniques. These lines fulfill their biological cycle normally (normal growth in soil, production of viable seeds) and show a relatively mild increase in transglutaminase activity (127%). These overexpressors of transglutaminase (OE TGase) have an extended stroma thylakoid network (71% higher number of PSIIβ centers), similar chlorophyll content (-4%), higher linear electron flow (+13%), and higher threshold of photoprotection activation (∼100%). On the other hand OE TGase showed a reduced maximum photochemistry of PSII (-6.5%), a smaller antenna per photosystem II (-25%), a lower photoprotective "energization" quenching or qE (-77% at 490 μmol photons m(-2) s(-1)) due to a higher threshold of qE activation and slightly lower light induced proton motive force (-17%). The role of the polyamines and of the transglutaminase in the regulation of chemiosmosis and photoprotection in chloroplasts is discussed.
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Affiliation(s)
| | | | - Josep M. Torné
- Department of Molecular Genetics, Center for Research in Agricultural GenomicsBarcelona, Spain
| | - Mireya Santos
- Department of Molecular Genetics, Center for Research in Agricultural GenomicsBarcelona, Spain
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Mellidou I, Moschou PN, Ioannidis NE, Pankou C, Gėmes K, Valassakis C, Andronis EA, Beris D, Haralampidis K, Roussis A, Karamanoli A, Matsi T, Kotzabasis K, Constantinidou HI, Roubelakis-Angelakis KA. Silencing S-Adenosyl-L-Methionine Decarboxylase (SAMDC) in Nicotiana tabacum Points at a Polyamine-Dependent Trade-Off between Growth and Tolerance Responses. FRONTIERS IN PLANT SCIENCE 2016; 7:379. [PMID: 27064210 PMCID: PMC4814703 DOI: 10.3389/fpls.2016.00379] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 03/11/2016] [Indexed: 05/02/2023]
Abstract
Polyamines (PAs) are nitrogenous molecules that are indispensable for cell viability and with an agreed-on role in the modulation of stress responses. Tobacco plants with downregulated SAMDC (AS-SAMDC) exhibit reduced PAs synthesis but normal levels of PA catabolism. We used AS-SAMDC to increase our understanding on the role of PAs in stress responses. Surprisingly, at control conditions AS-SAMDC plants showed increased biomass and altered developmental characteristics, such as increased height and leaf number. On the contrary, during salt stress AS-SAMDC plants showed reduced vigor when compared to the WT. During salt stress, the AS-SAMDC plants although showing compensatory readjustments of the antioxidant machinery and of photosynthetic apparatus, they failed to sustain their vigor. AS-SAMDC sensitivity was accompanied by inability to effectively control H2O2 levels and concentrations of monovalent and divalent cations. In accordance with these findings, we suggest that PAs may regulate the trade-off between growth and tolerance responses.
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Affiliation(s)
- Ifigeneia Mellidou
- Department of Crop Production, School of Agriculture, Aristotle University of ThessalonikiThessaloniki, Greece
| | - Panagiotis N. Moschou
- Department of Plant Biology and Linnean Center of Plant Sciences, Uppsala BioCentrum, Swedish University of Agricultural SciencesUppsala, Sweden
| | | | - Chryssa Pankou
- Department of Crop Production, School of Agriculture, Aristotle University of ThessalonikiThessaloniki, Greece
| | - Katalin Gėmes
- Biological Research Centre, Hungarian Academy of SciencesSzeged, Hungary
| | | | | | - Despoina Beris
- Department of Biology, National and Kapodistrian University of AthensAthens, Greece
| | - Kosmas Haralampidis
- Department of Biology, National and Kapodistrian University of AthensAthens, Greece
| | - Andreas Roussis
- Department of Biology, National and Kapodistrian University of AthensAthens, Greece
| | - Aikaterini Karamanoli
- Department of Crop Production, School of Agriculture, Aristotle University of ThessalonikiThessaloniki, Greece
| | - Theodora Matsi
- Department of Crop Production, School of Agriculture, Aristotle University of ThessalonikiThessaloniki, Greece
| | | | - Helen-Isis Constantinidou
- Department of Crop Production, School of Agriculture, Aristotle University of ThessalonikiThessaloniki, Greece
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Malliarakis D, Tsiavos T, Ioannidis NE, Kotzabasis K. Spermine and lutein quench chlorophyll fluorescence in isolated PSII antenna complexes. JOURNAL OF PLANT PHYSIOLOGY 2015; 183:108-13. [PMID: 26121079 DOI: 10.1016/j.jplph.2015.06.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Revised: 06/08/2015] [Accepted: 06/11/2015] [Indexed: 05/03/2023]
Abstract
Non photochemical quenching is a spontaneous mechanism that protects plants and algae from photodamage. In the last two decades, carotenoids through the xanthophylls cycle have been proposed to play a key role in quenching of chlorophyll. More recently, the involvement of endogenous polyamines in energy-dependent component of non photochemical quenching has been suggested by several research groups. In the present contribution, the combined effect of spermine and the xanthophylls, zeaxanthin and lutein on the fluorescence of antenna complexes of photosystem II was tested in vitro. Lutein caused significant quenching on trimeric and monomeric antenna complexes, whereas zeaxanthin under our experimental conditions had negligible effect. Spermine has been shown to allow fluorescence quenching to be induced in isolated antenna in the absence of ΔpH and to accelerate quenching formation. The simultaneous treatment of spermine and lutein maximizes quenching even at relatively low concentrations.
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Affiliation(s)
- Dimitris Malliarakis
- Department of Biology, University of Crete, Voutes University Campus, GR-70013 Heraklion, Crete, Greece
| | - Theodoros Tsiavos
- Department of Biology, University of Crete, Voutes University Campus, GR-70013 Heraklion, Crete, Greece
| | - Nikolaos E Ioannidis
- Department of Biology, University of Crete, Voutes University Campus, GR-70013 Heraklion, Crete, Greece.
| | - Kiriakos Kotzabasis
- Department of Biology, University of Crete, Voutes University Campus, GR-70013 Heraklion, Crete, Greece.
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Tsiavos T, Ioannidis NE, Tsortos A, Gizeli E, Kotzabasis K. Spermine is a potent modulator of proton transport through LHCII. JOURNAL OF PLANT PHYSIOLOGY 2015; 177:44-50. [PMID: 25659334 DOI: 10.1016/j.jplph.2015.01.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Revised: 01/18/2015] [Accepted: 01/20/2015] [Indexed: 06/04/2023]
Abstract
The effect of spermine on proton transport across large unilamellar liposomes containing incorporated complexes of the PSII antenna has been studied with the application of a pH-sensitive dye entrapped inside the vesicles. Both monomeric LHCbs and trimeric LHCII increased the permeability of proteoliposomes to protons when in a partly aggregated state within the lipid membrane. We have previously shown that a spermine-induced conformational change in LHCII results in its aggregation and ultimately in the enhancement of excitation energy as heat (qE). In this paper, spermine-induced aggregation of LHCII was found to facilitate proton transport across the proteoliposomes, indicating that a second protective mechanism (other than qE) might exist and might be regulated in vivo by polyamines when photosynthesis is saturated in excess light.
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Affiliation(s)
- Theodoros Tsiavos
- Department of Biology, University of Crete, Voutes University Campus, GR-70013 Heraklion, Crete, Greece
| | - Nikolaos E Ioannidis
- Department of Biology, University of Crete, Voutes University Campus, GR-70013 Heraklion, Crete, Greece
| | - Achilleas Tsortos
- Institute of Molecular Biology and Biotechnology, FORTH, GR-70013 Heraklion, Crete, Greece
| | - Electra Gizeli
- Department of Biology, University of Crete, Voutes University Campus, GR-70013 Heraklion, Crete, Greece; Institute of Molecular Biology and Biotechnology, FORTH, GR-70013 Heraklion, Crete, Greece
| | - Kiriakos Kotzabasis
- Department of Biology, University of Crete, Voutes University Campus, GR-70013 Heraklion, Crete, Greece.
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Sobieszczuk-Nowicka E, Legocka J. Plastid-associated polyamines: their role in differentiation, structure, functioning, stress response and senescence. PLANT BIOLOGY (STUTTGART, GERMANY) 2014; 16:297-305. [PMID: 23889994 DOI: 10.1111/plb.12058] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 05/06/2013] [Indexed: 05/03/2023]
Abstract
Polyamines are low-molecular weight biogenic amines. They are a specific group of cell growth and development regulators. In the past decade biochemical, molecular and genetic studies have contributed much to a better understanding of the biological role of polyamines in the plant cell. Substantial evidence has also been added to our understanding of the role of polyamines in plastid development. In developing chloroplasts, polyamines serve as a nitrogen source for protein and chlorophyll synthesis. In chloroplast structure, thylakoid proteins linked to polyamines belong mainly to antenna proteins of light-harvesting chlorophyll a/b-protein complexes. The fact that LHCII oligomeric forms are much more intensely labelled by polyamines, in comparison to monomeric forms, suggests that polyamines participate in oligomer stabilisation. In plastid metabolism, polyamines modulate effectiveness of photosynthesis. The role of polyamines in mature chloroplasts is also related to the photo-adaptation of the photosynthetic apparatus to low and high light intensity and its response to environmental stress. The occurrence of polyamines and enzymes participating in their metabolism at every stage of plastid development indicates that polyamines play a role in plastid differentiation, structure, functioning and senescence.
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Affiliation(s)
- E Sobieszczuk-Nowicka
- Department of Plant Physiology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
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Ioannidis NE, Lopera O, Santos M, Torné JM, Kotzabasis K. Role of plastid transglutaminase in LHCII polyamination and thylakoid electron and proton flow. PLoS One 2012; 7:e41979. [PMID: 22870182 PMCID: PMC3411467 DOI: 10.1371/journal.pone.0041979] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 06/28/2012] [Indexed: 01/09/2023] Open
Abstract
Transglutaminases function as biological glues in animal cells, plant cells and microbes. In energy producing organelles such as chloroplasts the presence of transglutaminases was recently confirmed. Furthermore, a plastidial transglutaminase has been cloned from maize and the first plants overexpressing tgz are available (Nicotiana tabacum TGZ OE). Our hypothesis is that the overexpression of plastidal transglutaminase will alter photosynthesis via increased polyamination of the antenna of photosystem II. We have used standard analytical tools to separate the antenna from photosystem II in wild type and modified plants, 6 specific antibodies against LHCbs to confirm their presence and sensitive HPLC method to quantify the polyamination level of these proteins. We report that bound spermidine and spermine were significantly increased (∼80%) in overexpressors. Moreover, we used recent advances in in vivo probing to study simultaneously the proton and electron circuit of thylakoids. Under physiological conditions overexpressors show a 3-fold higher sensitivity of the antenna down regulation loop (qE) to the elicitor (luminal protons) which is estimated as the ΔpH component of thylakoidal proton motive force. In addition, photosystem (hyper-PSIIα) with an exceptionally high antenna (large absorption cross section), accumulate in transglutaminase over expressers doubling the rate constant of light energy utilization (Kα) and promoting thylakoid membrane stacking. Polyamination of antenna proteins is a previously unrecognized mechanism for the modulation of the size (antenna absorption cross section) and sensitivity of photosystem II to down regulation. Future research will reveal which peptides and which residues of the antenna are responsible for such effects.
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Affiliation(s)
- Nikolaos E. Ioannidis
- Department of Biology, University of Crete, Voutes University Campus, Heraklion, Crete, Greece
- Departament de Genètica Molecular, Centre for Research in Agricultural Genomics, CRAG (CSIC-IRTA-UAB-UB), Barcelona, Spain
| | - Oriol Lopera
- Departament de Genètica Molecular, Centre for Research in Agricultural Genomics, CRAG (CSIC-IRTA-UAB-UB), Barcelona, Spain
| | - Mireya Santos
- Departament de Genètica Molecular, Centre for Research in Agricultural Genomics, CRAG (CSIC-IRTA-UAB-UB), Barcelona, Spain
| | - Josep M. Torné
- Departament de Genètica Molecular, Centre for Research in Agricultural Genomics, CRAG (CSIC-IRTA-UAB-UB), Barcelona, Spain
| | - Kiriakos Kotzabasis
- Department of Biology, University of Crete, Voutes University Campus, Heraklion, Crete, Greece
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