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Johnson MP, Wientjes E. The relevance of dynamic thylakoid organisation to photosynthetic regulation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1861:148039. [PMID: 31228404 DOI: 10.1016/j.bbabio.2019.06.011] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 06/14/2019] [Accepted: 06/15/2019] [Indexed: 12/11/2022]
Abstract
The higher plant chloroplast thylakoid membrane system performs the light-dependent reactions of photosynthesis. These provide the ATP and NADPH required for the fixation of CO2 into biomass by the Calvin-Benson cycle and a range of other metabolic reactions in the stroma. Land plants are frequently challenged by fluctuations in their environment, such as light, nutrient and water availability, which can create a mismatch between the amounts of ATP and NADPH produced and the amounts required by the downstream metabolism. Left unchecked, such imbalances can lead to the production of reactive oxygen species that damage the plant and harm productivity. Fortunately, plants have evolved a complex range of regulatory processes to avoid or minimize such deleterious effects by controlling the efficiency of light harvesting and electron transfer in the thylakoid membrane. Generally the regulation of the light reactions has been studied and conceptualised at the microscopic level of protein-protein and protein-ligand interactions, however in recent years dynamic changes in the thylakoid macrostructure itself have been recognised to play a significant role in regulating light harvesting and electron transfer. Here we review the evidence for the involvement of macrostructural changes in photosynthetic regulation and review the techniques that brought this evidence to light.
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Affiliation(s)
- Matthew P Johnson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom.
| | - Emilie Wientjes
- Laboratory of Biophysics, Wageningen University, Stippeneng 4, 6708 WE Wageningen, the Netherlands
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52
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Gerganova MT, Faik AK, Velitchkova MY. Acquired tolerance of the photosynthetic apparatus to photoinhibition as a result of growing Solanum lycopersicum at moderately higher temperature and light intensity. FUNCTIONAL PLANT BIOLOGY : FPB 2019; 46:555-566. [PMID: 30940333 DOI: 10.1071/fp18264] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 02/02/2019] [Indexed: 05/26/2023]
Abstract
The kinetics of photoinhibition in detached leaves from tomato plants (Solanium lycopersicum L. cv. M82) grown for 6 days under different combinations of optimal and moderately high temperature and optimal and high light intensity were studied. The inhibition of PSII was evaluated by changes in maximal quantum yield, the coefficient of photochemical quenching and the quantum yield of PSII. The changes of PSI activity was estimated by the redox state of P700. The involvement of different possible protective processes was checked by determination of nonphotochemical quenching and cyclic electron flow around PSI. To evaluate to what extent the photosynthetic apparatus and its response to high light treatment was affected by growth conditions, the kinetics of photoinhibition in isolated thylakoid membranes were also studied. The photochemical activities of both photosystems and changes in the energy distribution and interactions between them were evaluated by means of a Clark electrode and 77 K fluorescence analysis. The data showed an increased tolerance to photoinhibition in plants grown under a combination of moderately high temperature and light intensity, which was related to the stimulation of cyclic electron flow, PSI activity and rearrangements of pigment-protein complexes, leading to a decrease in the excitation energy delivered to PSII.
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Affiliation(s)
- Milena T Gerganova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Academician G. Bonchev str. Bl. 21, Sofia 1113, Bulgaria
| | - Aygyun K Faik
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Academician G. Bonchev str. Bl. 21, Sofia 1113, Bulgaria
| | - Maya Y Velitchkova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Academician G. Bonchev str. Bl. 21, Sofia 1113, Bulgaria; and Corresponding author.
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Osmond B, Chow WS, Pogson BJ, Robinson SA. Probing functional and optical cross-sections of PSII in leaves during state transitions using fast repetition rate light induced fluorescence transients. FUNCTIONAL PLANT BIOLOGY : FPB 2019; 46:567-583. [PMID: 32172734 DOI: 10.1071/fp18054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 02/07/2019] [Indexed: 05/11/2023]
Abstract
Plants adjust the relative sizes of PSII and PSI antennae in response to the spectral composition of weak light favouring either photosystem by processes known as state transitions (ST), attributed to a discrete antenna migration involving phosphorylation of light-harvesting chlorophyll-protein complexes in PSII. Here for the first time we monitored the extent and dynamics of ST in leaves from estimates of optical absorption cross-section (relative PSII antenna size; aPSII). These estimates were obtained from in situ measurements of functional absorption cross-section (σPSII) and maximum photochemical efficiency of PSII (φPSII); i.e. aPSII = σPSII/φPSII (Kolber et al. 1998) and other parameters from a light induced fluorescence transient (LIFT) device (Osmond et al. 2017). The fast repetition rate (FRR) QA flash protocol of this instrument monitors chlorophyll fluorescence yields with reduced QA irrespective of the redox state of plastoquinone (PQ), as well as during strong ~1 s white light pulses that fully reduce the PQ pool. Fitting this transient with the FRR model monitors kinetics of PSII → PQ, PQ → PSI, and the redox state of the PQ pool in the 'PQ pool control loop' that underpins ST, with a time resolution of a few seconds. All LIFT/FRR criteria confirmed the absence of ST in antenna mutant chlorina-f2 of barley and asLhcb2-12 of Arabidopsis, as well as STN7 kinase mutants stn7 and stn7/8. In contrast, wild-type barley and Arabidopsis genotypes Col, npq1, npq4, OEpsbs, pgr5 bkg and pgr5, showed normal ST. However, the extent of ST (and by implication the size of the phosphorylated LHCII pool participating in ST) deduced from changes in a'PSII and other parameters with reduced QA range up to 35%. Estimates from strong WL pulses in the same assay were only ~10%. The larger estimates of ST from the QA flash are discussed in the context of contemporary dynamic structural models of ST involving formation and participation of PSII and PSI megacomplexes in an 'energetically connected lake' of phosphorylated LHCII trimers (Grieco et al. 2015). Despite the absence of ST, asLhcb2-12 displays normal wild-type modulation of electron transport rate (ETR) and the PQ pool during ST assays, reflecting compensatory changes in antenna LHCIIs in this genotype. Impaired LHCII phosphorylation in stn7 and stn7/8 accelerates ETR from PSII →PQ, over-reducing the PQ pool and abolishing the yield difference between the QA flash and WL pulse, with implications for photochemical and thermal phases of the O-J-I-P transient.
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Affiliation(s)
- Barry Osmond
- Centre for Sustainable Ecosystem Solutions, School of Biological Sciences, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia; and Division of Plant Sciences, Research School of Biology, The Australian National University, 46 Sullivan's Creek Road, Acton, ACT 2601, Australia; and Corresponding author.
| | - Wah Soon Chow
- Division of Plant Sciences, Research School of Biology, The Australian National University, 46 Sullivan's Creek Road, Acton, ACT 2601, Australia
| | - Barry J Pogson
- Division of Plant Sciences, Research School of Biology, The Australian National University, 46 Sullivan's Creek Road, Acton, ACT 2601, Australia
| | - Sharon A Robinson
- Centre for Sustainable Ecosystem Solutions, School of Biological Sciences, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia
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Borisova-Mubarakshina MM, Vetoshkina DV, Ivanov BN. Antioxidant and signaling functions of the plastoquinone pool in higher plants. PHYSIOLOGIA PLANTARUM 2019; 166:181-198. [PMID: 30706486 DOI: 10.1111/ppl.12936] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 01/23/2019] [Accepted: 01/25/2019] [Indexed: 05/25/2023]
Abstract
The review covers data representing the plastoquinone pool as the component integrated in plant antioxidant defense and plant signaling. The main goal of the review is to discuss the evidence describing the plastoquinone-involved biochemical reactions, which are incorporated in maintaining the sustainability of higher plants to stress conditions. In this context, the analysis of the reactions of various redox forms of plastoquinone with oxygen species is presented. The review describes how these reactions can constitute both the antioxidant and signaling functions of the pool. Special attention is paid to the reaction of superoxide anion radicals with plastohydroquinone molecules, producing hydrogen peroxide as signal molecules. Attention is also given to the processes affecting the redox state of the plastoquinone pool because the redox state of the pool is of special importance for antioxidant defense and signaling.
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Affiliation(s)
| | - Daria V Vetoshkina
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Pushchino, Russia
| | - Boris N Ivanov
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Pushchino, Russia
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55
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Nama S, Madireddi SK, Yadav RM, Subramanyam R. Non-photochemical quenching-dependent acclimation and thylakoid organization of Chlamydomonas reinhardtii to high light stress. PHOTOSYNTHESIS RESEARCH 2019; 139:387-400. [PMID: 29982908 DOI: 10.1007/s11120-018-0551-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 06/30/2018] [Indexed: 05/19/2023]
Abstract
Light is essential for all photosynthetic organisms while an excess of it can lead to damage mainly the photosystems of the thylakoid membrane. In this study, we have grown Chlamydomonas reinhardtii cells in different intensities of high light to understand the photosynthetic process with reference to thylakoid membrane organization during its acclimation process. We observed, the cells acclimatized to long-term response to high light intensities of 500 and 1000 µmol m-2 s-1 with faster growth and more biomass production when compared to cells at 50 µmol m-2 s-1 light intensity. The ratio of Chl a/b was marginally decreased from the mid-log phase of growth at the high light intensity. Increased level of zeaxanthin and LHCSR3 expression was also found which is known to play a key role in non-photochemical quenching (NPQ) mechanism for photoprotection. Changes in photosynthetic parameters were observed such as increased levels of NPQ, marginal change in electron transport rate, and many other changes which demonstrate that cells were acclimatized to high light which is an adaptive mechanism. Surprisingly, PSII core protein contents have marginally reduced when compared to peripherally arranged LHCII in high light-grown cells. Further, we also observed alterations in stromal subunits of PSI and low levels of PsaG, probably due to disruption of PSI assembly and also its association with LHCI. During the process of acclimation, changes in thylakoid organization occurred in high light intensities with reduction of PSII supercomplex formation. This change may be attributed to alteration of protein-pigment complexes which are in agreement with circular dichoism spectra of high light-acclimatized cells, where decrease in the magnitude of psi-type bands indicates changes in ordered arrays of PSII-LHCII supercomplexes. These results specify that acclimation to high light stress through NPQ mechanism by expression of LHCSR3 and also observed changes in thylakoid protein profile/supercomplex formation lead to low photochemical yield and more biomass production in high light condition.
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Affiliation(s)
- Srilatha Nama
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, Telangana, India
| | - Sai Kiran Madireddi
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, Telangana, India
| | - Ranay Mohan Yadav
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, Telangana, India
| | - Rajagopal Subramanyam
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, Telangana, India.
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56
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Popova AV, Dobrev K, Velitchkova M, Ivanov AG. Differential temperature effects on dissipation of excess light energy and energy partitioning in lut2 mutant of Arabidopsis thaliana under photoinhibitory conditions. PHOTOSYNTHESIS RESEARCH 2019; 139:367-385. [PMID: 29725995 DOI: 10.1007/s11120-018-0511-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/22/2018] [Indexed: 06/08/2023]
Abstract
The high-light-induced alterations in photosynthetic performance of photosystem II (PSII) and photosystem I (PSI) as well as effectiveness of dissipation of excessive absorbed light during illumination for different periods of time at room (22 °C) and low (8-10 °C) temperature of leaves of Arabidopsis thaliana, wt and lut2, were followed with the aim of unraveling the role of lutein in the process of photoinhibition. Photosynthetic parameters of PSII and PSI were determined on whole leaves by PAM fluorometer and oxygen evolving activity-by a Clark-type electrode. In thylakoid membranes, isolated from non-illuminated and illuminated for 4.5 h leaves of wt and lut2 the photochemical activity of PSII and PSI and energy interaction between the main pigment-protein complexes was determined. Results indicate that in non-illuminated leaves of lut2 the maximum rate of oxygen evolution and energy utilization in PSII is lower, excitation pressure of PSII is higher and cyclic electron transport around PSI is faster than in wt leaves. Under high-light illumination, lut2 leaves are more sensitive in respect to PSII performance and the extent of increase of excitation pressure of PSII, ΦNO, and cyclic electron transport around PSI are higher than in wt leaves, especially when illumination is performed at low temperature. Significant part of the excessive light energy is dissipated via mechanism, not dependent on ∆pH and to functioning of xanthophyll cycle in LHCII, operating more intensively in lut2 leaves.
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Affiliation(s)
- Antoaneta V Popova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str. bl. 21, 1113, Sofia, Bulgaria.
| | - Konstantin Dobrev
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str. bl. 21, 1113, Sofia, Bulgaria
| | - Maya Velitchkova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str. bl. 21, 1113, Sofia, Bulgaria
| | - Alexander G Ivanov
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str. bl. 21, 1113, Sofia, Bulgaria
- Department of Biology, University of Western Ontario, 1151 Richmond Str. N., London, ON, N6A 5B7, Canada
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57
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Ancín M, Fernández-San Millán A, Larraya L, Morales F, Veramendi J, Aranjuelo I, Farran I. Overexpression of thioredoxin m in tobacco chloroplasts inhibits the protein kinase STN7 and alters photosynthetic performance. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:1005-1016. [PMID: 30476130 PMCID: PMC6363096 DOI: 10.1093/jxb/ery415] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 11/12/2018] [Indexed: 05/06/2023]
Abstract
The activity of the protein kinase STN7, involved in phosphorylation of the light-harvesting complex II (LHCII) proteins, has been reported as being co-operatively regulated by the redox state of the plastoquinone pool and the ferredoxin-thioredoxin (Trx) system. The present study aims to investigate the role of plastid Trxs in STN7 regulation and their impact on photosynthesis. For this purpose, tobacco plants overexpressing Trx f or m from the plastid genome were characterized, demonstrating that only Trx m overexpression was associated with a complete loss of LHCII phosphorylation that did not correlate with decreased STN7 levels. The absence of phosphorylation in Trx m-overexpressing plants impeded migration of LHCII from PSII to PSI, with the concomitant loss of PSI-LHCII complex formation. Consequently, the thylakoid ultrastructure was altered, showing reduced grana stacking. Moreover, the electron transport rate was negatively affected, showing an impact on energy-demanding processes such as the Rubisco maximum carboxylation capacity and ribulose 1,5-bisphosphate regeneration rate values, which caused a strong depletion in net photosynthetic rates. Finally, tobacco plants overexpressing a Trx m mutant lacking the reactive redox site showed equivalent physiological performance to the wild type, indicating that the overexpressed Trx m deactivates STN7 in a redox-dependent way.
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Affiliation(s)
- María Ancín
- Instituto de Agrobiotecnología (IdAB), Universidad Pública de Navarra-CSIC-Gobierno de Navarra, Campus Arrosadia, Pamplona, Spain
| | - Alicia Fernández-San Millán
- Instituto de Agrobiotecnología (IdAB), Universidad Pública de Navarra-CSIC-Gobierno de Navarra, Campus Arrosadia, Pamplona, Spain
| | - Luis Larraya
- Instituto de Agrobiotecnología (IdAB), Universidad Pública de Navarra-CSIC-Gobierno de Navarra, Campus Arrosadia, Pamplona, Spain
| | - Fermín Morales
- Instituto de Agrobiotecnología (IdAB), Universidad Pública de Navarra-CSIC-Gobierno de Navarra, Campus Arrosadia, Pamplona, Spain
- Estación Experimental de Aula Dei (EEAD), CSIC, Departamento Nutrición Vegetal, Zaragoza, Spain
| | - Jon Veramendi
- Instituto de Agrobiotecnología (IdAB), Universidad Pública de Navarra-CSIC-Gobierno de Navarra, Campus Arrosadia, Pamplona, Spain
| | - Iker Aranjuelo
- Instituto de Agrobiotecnología (IdAB), Universidad Pública de Navarra-CSIC-Gobierno de Navarra, Campus Arrosadia, Pamplona, Spain
| | - Inmaculada Farran
- Instituto de Agrobiotecnología (IdAB), Universidad Pública de Navarra-CSIC-Gobierno de Navarra, Campus Arrosadia, Pamplona, Spain
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58
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Capretti A, Ringsmuth AK, van Velzen JF, Rosnik A, Croce R, Gregorkiewicz T. Nanophotonics of higher-plant photosynthetic membranes. LIGHT, SCIENCE & APPLICATIONS 2019; 8:5. [PMID: 30651980 PMCID: PMC6325066 DOI: 10.1038/s41377-018-0116-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Revised: 12/15/2018] [Accepted: 12/16/2018] [Indexed: 05/25/2023]
Abstract
The thylakoid membrane inside chloroplasts hosts the light-dependent reactions of photosynthesis. Its embedded protein complexes are responsible for light harvesting, excitation energy transfer, charge separation, and transport. In higher plants, when the illumination conditions vary, the membrane adapts its composition and nanoscale morphology, which is characterized by appressed and non-appressed regions known as grana and stroma lamellae, respectively. Here we investigate the nanophotonic regime of light propagation in chloroplasts of higher plants and identify novel mechanisms in the optical response of the thylakoid membrane. Our results indicate that the relative contributions of light scattering and absorption to the overall optical response of grana strongly depend on the concentration of the light-harvesting complexes. For the pigment concentrations typically found in chloroplasts, the two mechanisms have comparable strengths, and their relative value can be tuned by variations in the protein composition or in the granal diameter. Furthermore, we find that collective modes in ensembles of grana significantly increase light absorption at selected wavelengths, even in the presence of moderate biological disorder. Small variations in the granal separation or a large disorder can dismantle this collective response. We propose that chloroplasts use this mechanism as a strategy against dangerously high illumination conditions, triggering a transition to low-absorbing states. We conclude that the morphological separation of the thylakoid membrane in higher plants supports strong nanophotonic effects, which may be used by chloroplasts to regulate light absorption. This adaptive self-organization capability is of interest as a model for novel bioinspired optical materials for artificial photosynthesis, imaging, and sensing.
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Affiliation(s)
- A. Capretti
- Institute of Physics, University of Amsterdam, Amsterdam, Netherlands
| | - A. K. Ringsmuth
- Dep. Physics and Astronomy, VU University Amsterdam, Amsterdam, Netherlands
- Present Address: Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden
| | - J. F. van Velzen
- Institute of Physics, University of Amsterdam, Amsterdam, Netherlands
- Dep. Physics and Astronomy, VU University Amsterdam, Amsterdam, Netherlands
| | - A. Rosnik
- College of Chemistry, University of California, Berkeley, CA USA
| | - R. Croce
- Dep. Physics and Astronomy, VU University Amsterdam, Amsterdam, Netherlands
| | - T. Gregorkiewicz
- Institute of Physics, University of Amsterdam, Amsterdam, Netherlands
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59
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Petrova N, Todinova S, Paunov M, Kovács L, Taneva S, Krumova S. Thylakoid membrane unstacking increases LHCII thermal stability and lipid phase fluidity. J Bioenerg Biomembr 2018; 50:425-435. [PMID: 30607760 DOI: 10.1007/s10863-018-9783-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 12/20/2018] [Indexed: 11/26/2022]
Abstract
Thylakoids are highly protein-enriched membranes that harbor a number of multicomponent photosynthetic complexes. Similarly to other biological membranes the protein constituents are heterogeneously distributed laterally in the plane of the membrane, however the specific segregation into stacked (grana patches) and unstacked (stroma lamellae) membrane layers is a unique feature of the thylakoid. Both the lateral and the vertical arrangements of the integral membrane proteins within the three-dimensional thylakoid ultrastructure are thought to have important physiological function. In this work we explore the role of membrane stacking for the thermal stability of the photosynthetic complexes in thylakoid membranes. By means of circular dichroism and differential scanning calorimetry we demonstrate that the thermal stability of the monomeric and trimeric forms of the major light harvesting complex of photosystem II (LHCII) increases upon unstacking. This effect was suggested to be due to the detachment of LHCII from photosystem II and consequent attachment to photosystem I subunits and/or the fluidization of the lipid matrix upon unstacking. The changes in the physical properties of the protein and lipid membrane components upon unstacking result in strongly reduced photosystem II excitation energy utilization.
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Affiliation(s)
- Nia Petrova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Svetla Todinova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Momchil Paunov
- Department of Biophysics and Radiobiology, Faculty of Biology, Sofia University "St. Kliment Ohridski", Sofia, Bulgaria
| | - Lászlo Kovács
- Biological Research Centre, Institute of Plant Biology, Szeged, Hungary
| | - Stefka Taneva
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Sashka Krumova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria.
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60
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Albanese P, Manfredi M, Re A, Marengo E, Saracco G, Pagliano C. Thylakoid proteome modulation in pea plants grown at different irradiances: quantitative proteomic profiling in a non-model organism aided by transcriptomic data integration. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 96:786-800. [PMID: 30118564 DOI: 10.1111/tpj.14068] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 08/03/2018] [Accepted: 08/13/2018] [Indexed: 05/02/2023]
Abstract
Plant thylakoid membranes contain hundreds of proteins that closely interact to cope with ever-changing environmental conditions. We investigated how Pisum sativum L. (pea) grown at different irradiances optimizes light-use efficiency through the differential accumulation of thylakoid proteins. Thylakoid membranes from plants grown under low (LL), moderate (ML) and high (HL) light intensity were characterized by combining chlorophyll fluorescence measurements with quantitative label-free proteomic analysis. Protein sequences retrieved from available transcriptomic data considerably improved thylakoid proteome profiling, increasing the quantifiable proteins from 63 to 194. The experimental approach used also demonstrates that this integrative omics strategy is powerful for unravelling protein isoforms and functions that are still unknown in non-model organisms. We found that the different growth irradiances affect the electron transport kinetics but not the relative abundance of photosystems (PS) I and II. Two acclimation strategies were evident. The behaviour of plants acclimated to LL was compared at higher irradiances: (i) in ML, plants turn on photoprotective responses mostly modulating the PSII light-harvesting capacity, either accumulating Lhcb4.3 or favouring the xanthophyll cycle; (ii) in HL, plants reduce the pool of light-harvesting complex II and enhance the PSII repair cycle. When growing at ML and HL, plants accumulate ATP synthase, boosting both cyclic and linear electron transport by finely tuning the ΔpH across the membrane and optimizing protein trafficking by adjusting the thylakoid architecture. Our results provide a quantitative snapshot of how plants coordinate light harvesting, electron transport and protein synthesis by adjusting the thylakoid membrane proteome in a light-dependent manner.
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Affiliation(s)
- Pascal Albanese
- Applied Science and Technology Department-BioSolar Lab, Politecnico di Torino, Environment Park, Via Livorno 60, 10144, Torino, Italy
| | - Marcello Manfredi
- ISALIT-Department of Science and Technological Innovation, University of Eastern Piedmont, Viale T. Michel 11, 15121, Alessandria, Italy
- Department of Science and Technological Innovation, University of Eastern Piedmont, Viale T. Michel 11, 15121, Alessandria, Italy
| | - Angela Re
- Center for Sustainable Future Technologies-CSFT@POLITO, Istituto Italiano di Tecnologia, Corso Trento 21, 10129, Torino, Italy
| | - Emilio Marengo
- Department of Science and Technological Innovation, University of Eastern Piedmont, Viale T. Michel 11, 15121, Alessandria, Italy
| | - Guido Saracco
- Applied Science and Technology Department-BioSolar Lab, Politecnico di Torino, Environment Park, Via Livorno 60, 10144, Torino, Italy
| | - Cristina Pagliano
- Applied Science and Technology Department-BioSolar Lab, Politecnico di Torino, Environment Park, Via Livorno 60, 10144, Torino, Italy
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61
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Giovanardi M, Pantaleoni L, Ferroni L, Pagliano C, Albanese P, Baldisserotto C, Pancaldi S. In pea stipules a functional photosynthetic electron flow occurs despite a reduced dynamicity of LHCII association with photosystems. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:1025-1038. [DOI: 10.1016/j.bbabio.2018.05.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 05/17/2018] [Accepted: 05/23/2018] [Indexed: 12/18/2022]
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62
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Nitric Oxide Enhancing Resistance to PEG-Induced Water Deficiency is Associated with the Primary Photosynthesis Reaction in Triticum aestivum L. Int J Mol Sci 2018; 19:ijms19092819. [PMID: 30231569 PMCID: PMC6164216 DOI: 10.3390/ijms19092819] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 09/10/2018] [Accepted: 09/12/2018] [Indexed: 12/30/2022] Open
Abstract
Photosynthesis is affected by water-deficiency (WD) stress, and nitric oxide (NO) is a free radical that participates in the photosynthesis process. Previous studies have suggested that NO regulates excitation-energy distribution of photosynthesis under WD stress. Here, quantitative phosphoproteomic profiling was conducted using iTRAQ. Differentially phosphorylated protein species (DEPs) were identified in leaves of NO- or polyethylene glycol (PEG)-treated wheat seedlings (D), and in control seedlings. From 1396 unique phosphoproteins, 2257 unique phosphorylated peptides and 2416 phosphorylation sites were identified. Of these, 96 DEPs displayed significant changes (≥1.50-fold, p < 0.01). These DEPs are involved in photosynthesis, signal transduction, etc. Furthermore, phosphorylation of several DEPs was upregulated by both D and NO treatments, but downregulated only in NO treatment. These differences affected the chlorophyll A–B binding protein, chloroplast post-illumination chlorophyll-fluorescence-increase protein, and SNT7, implying that NO indirectly regulated the absorption and transport of light energy in photosynthesis in response to WD stress. The significant difference of chlorophyll (Chl) content, Chl a fluorescence-transient, photosynthesis index, and trapping and transport of light energy further indicated that exogenous NO under D stress enhanced the primary photosynthesis reaction compared to D treatment. A putative pathway is proposed to elucidate NO regulation of the primary reaction of photosynthesis under WD.
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63
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Pan X, Ma J, Su X, Cao P, Chang W, Liu Z, Zhang X, Li M. Structure of the maize photosystem I supercomplex with light-harvesting complexes I and II. Science 2018; 360:1109-1113. [PMID: 29880686 DOI: 10.1126/science.aat1156] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 04/16/2018] [Indexed: 01/15/2023]
Abstract
Plants regulate photosynthetic light harvesting to maintain balanced energy flux into photosystems I and II (PSI and PSII). Under light conditions favoring PSII excitation, the PSII antenna, light-harvesting complex II (LHCII), is phosphorylated and forms a supercomplex with PSI core and the PSI antenna, light-harvesting complex I (LHCI). Both LHCI and LHCII then transfer excitation energy to the PSI core. We report the structure of maize PSI-LHCI-LHCII solved by cryo-electron microscopy, revealing the recognition site between LHCII and PSI. The PSI subunits PsaN and PsaO are observed at the PSI-LHCI interface and the PSI-LHCII interface, respectively. Each subunit relays excitation to PSI core through a pair of chlorophyll molecules, thus revealing previously unseen paths for energy transfer between the antennas and the PSI core.
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Affiliation(s)
- Xiaowei Pan
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China
| | - Jun Ma
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China
| | - Xiaodong Su
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China
| | - Peng Cao
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China
| | - Wenrui Chang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China.,University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Zhenfeng Liu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China.,University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Xinzheng Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China. .,University of Chinese Academy of Sciences, Beijing 100049, P.R. China.,Center for Biological Imaging, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China
| | - Mei Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China.
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64
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Murakami K, Matsuda R, Fujiwara K. A Mathematical Model of Photosynthetic Electron Transport in Response to the Light Spectrum Based on Excitation Energy Distributed to Photosystems. PLANT & CELL PHYSIOLOGY 2018; 59:1643-1651. [PMID: 29697808 DOI: 10.1093/pcp/pcy085] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
To enable us to analyze more systematically the effects of the spectral distribution of light (i.e. light quality) on photosynthetic electron transport, we propose a simple mathematical model which describes electron transport reactions under light-limited conditions based on the excitation energy distributed to the photosystems. The model assumes that the rate-limiting photosystem performs the photochemical reaction at its maximum yield, while the yield in the other photosystem is passively down-regulated to equalize the rates of linear electron transport through the photosystems. Using intact cucumber leaves, we tested the model by comparing actual and estimated photosynthetic parameters under several combinations of photon flux densities of red and far-red lights (R and FR, respectively). Simultaneously provided R and FR yielded greater gross photosynthetic rates than the sums of the rates under only R and only FR, which is known as the 'enhancement effect'. The present model reproduced these non-additive increases in the gross photosynthetic rates in response to supplemental FR to R and provided more accurate estimates than an existing method that did not take the enhancement effect into account (root mean square errors: 0.11 and 0.21 μmol m-2 s-1, respectively). Using the present model, the photon flux density of the supplemental FR which gives the changing point of rate-limiting photosystem and the photochemical yields of the non-rate-limiting photosystems were estimated reasonably well. The present study has therefore formulated a simplified quantitative electron transport model in response to the light spectrum based on generally accepted concepts and demonstrated its validity experimentally.
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Affiliation(s)
- Keach Murakami
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo, Japan
| | - Ryo Matsuda
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo, Japan
| | - Kazuhiro Fujiwara
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo, Japan
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65
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Yan D, Beardall J, Gao K. Variation in cell size of the diatom Coscinodiscus granii influences photosynthetic performance and growth. PHOTOSYNTHESIS RESEARCH 2018; 137:41-52. [PMID: 29322482 DOI: 10.1007/s11120-017-0476-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Accepted: 12/27/2017] [Indexed: 06/07/2023]
Abstract
Cell size has implications for the package effect in photon absorption as well as for metabolic scaling of metabolism. In this study, we have avoided species-related differences by using isolates of the marine planktonic diatom Coscinodiscus granii with cells of different sizes and grown at different light intensities to investigate their energy allocation strategies. To make full use of incident light, several fold variations in cellular chlorophyll a content were employed across cell size. This modulation of pigment-related light absorbance was deemed effective as similar light absorbing capacities were found in all treatments. Unexpected low values of O2 evolution rate at the highest irradiance level of 450 μmol photons m-2 s-1 were found in medium and large cells, regardless of more photons being absorbed under these conditions, suggesting the operation of alternative electron flows acting as electron sinks. The growth rate was generally larger at higher irradiance levels except for the large cells, in which growth slowed at 450 μmol photons m-2 s-1, suggesting that larger cells achieved a balance between growth and photoprotection by sacrificing growth rate when exposed to high light. Although the ratio of carbon demand to rates of uncatalysed CO2 diffusion to the cell surface reached around 20 in large cells grown under higher irradiance, the carbon fixation rate was not lowered, due to the presence of a highly effective carbon dioxide concentrating mechanism.
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Affiliation(s)
- Dong Yan
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, Fujian, China
| | - John Beardall
- School of Biological Sciences, Monash University, Clayton, VIC, 3800, Australia
| | - Kunshan Gao
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, Fujian, China.
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66
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Yamatani H, Kohzuma K, Nakano M, Takami T, Kato Y, Hayashi Y, Monden Y, Okumoto Y, Abe T, Kumamaru T, Tanaka A, Sakamoto W, Kusaba M. Impairment of Lhca4, a subunit of LHCI, causes high accumulation of chlorophyll and the stay-green phenotype in rice. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1027-1035. [PMID: 29304198 PMCID: PMC6019047 DOI: 10.1093/jxb/erx468] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 12/12/2017] [Indexed: 05/21/2023]
Abstract
Chlorophyll is an essential molecule for acquiring light energy during photosynthesis. Mutations that result in chlorophyll retention during leaf senescence are called 'stay-green' mutants. One of the several types of stay-green mutants, Type E, accumulates high levels of chlorophyll in the pre-senescent leaves, resulting in delayed yellowing. We isolated delayed yellowing1-1 (dye1-1), a rice mutant whose yellowing is delayed in the field. dye1-1 accumulated more chlorophyll than the wild-type in the pre-senescent and senescent leaves, but did not retain leaf functionality in the 'senescent green leaves', suggesting that dye1-1 is a Type E stay-green mutant. Positional cloning revealed that DYE1 encodes Lhca4, a subunit of the light-harvesting complex I (LHCI). In dye1-1, amino acid substitution occurs at the location of a highly conserved amino acid residue involved in pigment binding; indeed, a severely impaired structure of the PSI-LHCI super-complex in dye1-1 was observed in a blue native PAGE analysis. Nevertheless, the biomass and carbon assimilation rate of dye1-1 were comparable to those in the wild-type. Interestingly, Lhcb1, a trimeric LHCII protein, was highly accumulated in dye1-1, in the chlorophyll-protein complexes. The high accumulation of LHCII in the LHCI mutant dye1 suggests a novel functional interaction between LHCI and LHCII.
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Affiliation(s)
- Hiroshi Yamatani
- Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - Kaori Kohzuma
- Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - Michiharu Nakano
- Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - Tsuneaki Takami
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama, Japan
| | - Yusuke Kato
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama, Japan
| | - Yoriko Hayashi
- Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama, Japan
| | - Yuki Monden
- Graduate School of Agriculture, Kyoto University, Kyoto, Kyoto, Japan
| | - Yutaka Okumoto
- Graduate School of Agriculture, Kyoto University, Kyoto, Kyoto, Japan
| | - Tomoko Abe
- Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama, Japan
| | | | - Ayumi Tanaka
- Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan
| | - Wataru Sakamoto
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama, Japan
| | - Makoto Kusaba
- Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
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67
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Santabarbara S, Tibiletti T, Remelli W, Caffarri S. Kinetics and heterogeneity of energy transfer from light harvesting complex II to photosystem I in the supercomplex isolated from Arabidopsis. Phys Chem Chem Phys 2018; 19:9210-9222. [PMID: 28319223 DOI: 10.1039/c7cp00554g] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
State transitions are a phenomenon that maintains the excitation balance between photosystem II (PSII) and photosystem I (PSI-LHCI) by controlling their relative absorption cross-sections. Under light conditions exciting PSII preferentially, a trimeric LHCII antenna moves from PSII to PSI-LHCI to form the PSI-LHCI-LHCII supercomplex. In this work, the excited state dynamics in the PSI-LHCI and PSI-LHCI-LHCII supercomplexes isolated from Arabidopsis have been investigated by picosecond time-resolved fluorescence spectroscopy. The excited state decays were analysed using two approaches based on either (i) a sum of discrete exponentials or (ii) a continuous distribution of lifetimes. The results indicate that the energy transfer from LHCII to the bulk of the PSI antenna occurs with an average macroscopic transfer rate in the 35-65 ns-1 interval. Yet, the most satisfactory description of the data is obtained when considering a heterogeneous population containing two PSI-LHCI-LHCII supercomplexes characterised by a transfer time of ∼15 and ∼60 ns-1, likely due to the differences in the strength and orientation of LHCII harboured to PSI. Both these values are of the same order of magnitude of those estimated for the average energy transfer rates from the low energy spectral forms of LHCI to the bulk of the PSI antenna (15-40 ns-1), but they are slower than the transfer from the bulk antenna of PSI to the reaction centre (>150 ns-1), implying a relatively small kinetics bottleneck for the energy transfer from LHCII. Nevertheless, the kinetic limitation imposed by excited state diffusion has a negligible impact on the photochemical quantum efficiency of the supercomplex, which remains about 98% in the case of PSI-LHCI.
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Affiliation(s)
- Stefano Santabarbara
- Photosynthesis Research Unit, Centro di Studio per la Biologia Cellulare e Molecolare delle Piante, Via Celoria 26, 20133 Milan, Italy.
| | - Tania Tibiletti
- Aix Marseille Univ, CEA, CNRS UMR7265 BVME, Laboratoire de Génétique et Biophysique des Plantes, Marseille 13009, France
| | - William Remelli
- Photosynthesis Research Unit, Centro di Studio per la Biologia Cellulare e Molecolare delle Piante, Via Celoria 26, 20133 Milan, Italy.
| | - Stefano Caffarri
- Aix Marseille Univ, CEA, CNRS UMR7265 BVME, Laboratoire de Génétique et Biophysique des Plantes, Marseille 13009, France
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68
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Wood WHJ, MacGregor-Chatwin C, Barnett SFH, Mayneord GE, Huang X, Hobbs JK, Hunter CN, Johnson MP. Dynamic thylakoid stacking regulates the balance between linear and cyclic photosynthetic electron transfer. NATURE PLANTS 2018; 4:116-127. [PMID: 29379151 DOI: 10.1038/s41477-017-0092-7] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 12/13/2017] [Indexed: 05/05/2023]
Abstract
Upon transition of plants from darkness to light the initiation of photosynthetic linear electron transfer (LET) from H2O to NADP+ precedes the activation of CO2 fixation, creating a lag period where cyclic electron transfer (CET) around photosystem I (PSI) has an important protective role. CET generates ΔpH without net reduced NADPH formation, preventing overreduction of PSI via regulation of the cytochrome b 6 f (cytb 6 f) complex and protecting PSII from overexcitation by inducing non-photochemical quenching. The dark-to-light transition also provokes increased phosphorylation of light-harvesting complex II (LHCII). However, the relationship between LHCII phosphorylation and regulation of the LET/CET balance is not understood. Here, we show that the dark-to-light changes in LHCII phosphorylation profoundly alter thylakoid membrane architecture and the macromolecular organization of the photosynthetic complexes, without significantly affecting the antenna size of either photosystem. The grana diameter and number of membrane layers per grana are decreased in the light while the number of grana per chloroplast is increased, creating a larger contact area between grana and stromal lamellae. We show that these changes in thylakoid stacking regulate the balance between LET and CET pathways. Smaller grana promote more efficient LET by reducing the diffusion distance for the mobile electron carriers plastoquinone and plastocyanin, whereas larger grana enhance the partition of the granal and stromal lamellae plastoquinone pools, enhancing the efficiency of CET and thus photoprotection by non-photochemical quenching.
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Affiliation(s)
- William H J Wood
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK
| | | | - Samuel F H Barnett
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK
| | - Guy E Mayneord
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK
| | - Xia Huang
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK
| | - Jamie K Hobbs
- Department of Physics and Astronomy, University of Sheffield, Sheffield, UK
| | - C Neil Hunter
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK
| | - Matthew P Johnson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK.
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69
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Rantala S, Tikkanen M. Phosphorylation-induced lateral rearrangements of thylakoid protein complexes upon light acclimation. PLANT DIRECT 2018; 2:e00039. [PMID: 31245706 PMCID: PMC6508491 DOI: 10.1002/pld3.39] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 01/12/2018] [Accepted: 01/16/2018] [Indexed: 05/22/2023]
Abstract
Understanding the mechanistic basis of balanced excitation energy distribution between photosystem II and photosystem I (PSII and PSI) requires detailed investigation of the thylakoid light-harvesting system composed of energetically connected LHCII trimers. The exact mechanisms controlling the excitation energy distribution remain elusive, but reversible phosphorylation is known to be one important component. Here, we addressed the role of grana margins in regulation of excitation energy distribution, as these thylakoid domains host all the complexes of photosynthetic light reactions with dynamic response to environmental cues. First, the effect of detergents for the thylakoid membrane connectivity is explained. We show that a specific interaction between the separate LHCII trimers as well as between the LHCII trimers and the PSII and PSI-LHCI complexes is a prerequisite for energetically connected and functional thylakoid membrane. Second, we demonstrate that the optimization of light reactions under changing light conditions takes place in energetically connected LHCII lake and is attained by lateral rearrangements of the PSII-LHCII and PSI-LHCI-LHCII complexes depending especially on the phosphorylation status of the LHCII protein isoform LHCB2.
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Affiliation(s)
- Sanna Rantala
- Molecular Plant BiologyDepartment of BiochemistryUniversity of TurkuTurkuFinland
| | - Mikko Tikkanen
- Molecular Plant BiologyDepartment of BiochemistryUniversity of TurkuTurkuFinland
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70
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Murakami K, Matsuda R, Fujiwara K. Quantification of excitation energy distribution between photosystems based on a mechanistic model of photosynthetic electron transport. PLANT, CELL & ENVIRONMENT 2018; 41:148-159. [PMID: 28548208 DOI: 10.1111/pce.12986] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 04/16/2017] [Accepted: 04/25/2017] [Indexed: 06/07/2023]
Abstract
Absorbed light energy is converted into excitation energy. The excitation energy is distributed to photosystems depending on the wavelength and drives photochemical reactions. A non-destructive, mechanistic and quantitative method for estimating the fraction of the excitation energy distributed to photosystem II (f) was developed. For the f values for two simultaneously provided actinic lights (ALs) with different spectral distributions to be estimated, photochemical yields of the photosystems were measured under the ALs and were then fitted to an electron transport model assuming the balance between the electron transport rates through the photosystems. For the method to be tested using leaves with different properties in terms of the long-term and short-term acclimation (adjustment of photosystem stoichiometry and state transition, respectively), the f values for red and far-red light (R and FR) were estimated in leaves grown (~1 week) under white light without and with supplemental FR and adapted (~10 min) to R without and with supplemental FR. The f values for R were clearly greater than those for FR and those of leaves grown with and adapted to supplemental FR tended to be higher than the controls. These results are consistent with previous studies and therefore support the validity of the proposed method.
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Affiliation(s)
- Keach Murakami
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo, Tokyo, 113-8657, Japan
| | - Ryo Matsuda
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo, Tokyo, 113-8657, Japan
| | - Kazuhiro Fujiwara
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo, Tokyo, 113-8657, Japan
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71
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Rantala M, Tikkanen M, Aro EM. Proteomic characterization of hierarchical megacomplex formation in Arabidopsis thylakoid membrane. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 92:951-962. [PMID: 28980426 DOI: 10.1111/tpj.13732] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 09/26/2017] [Accepted: 09/28/2017] [Indexed: 06/07/2023]
Abstract
Conversion of solar energy into chemical energy in plant chloroplasts concomitantly modifies the thylakoid architecture and hierarchical interactions between pigment-protein complexes. Here, the thylakoids were isolated from light-acclimated Arabidopsis leaves and investigated with respect to the composition of the thylakoid protein complexes and their association into higher molecular mass complexes, the largest one comprising both photosystems (PSII and PSI) and light-harvesting chlorophyll a/b-binding complexes (LHCII). Because the majority of plant light-harvesting capacity is accommodated in LHCII complexes, their structural interaction with photosystem core complexes is extremely important for efficient light harvesting. Specific differences in the strength of LHCII binding to PSII core complexes and the formation of PSII supercomplexes are well characterized. Yet, the role of loosely bound L-LHCII that disconnects to a large extent during the isolation of thylakoid protein complexes remains elusive. Because L-LHCII apparently has a flexible role in light harvesting and energy dissipation, depending on environmental conditions, its close interaction with photosystems is a prerequisite for successful light harvesting in vivo. Here, to reveal the labile and fragile light-dependent protein interactions in the thylakoid network, isolated membranes were subjected to sequential solubilization using detergents with differential solubilization capacity and applying strict quality control. Optimized 3D-lpBN-lpBN-sodium dodecyl sulfate-polyacrylamide gel electrophoresis system demonstrated that PSII-LHCII supercomplexes, together with PSI complexes, hierarchically form larger megacomplexes via interactions with L-LHCII trimers. The polypeptide composition of LHCII trimers and the phosphorylation of Lhcb1 and Lhcb2 were examined to determine the light-dependent supramolecular organization of the photosystems into megacomplexes.
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Affiliation(s)
- Marjaana Rantala
- Molecular Plant Biology, Department of Biochemistry, University of Turku, Turku, FI-20014, Finland
| | - Mikko Tikkanen
- Molecular Plant Biology, Department of Biochemistry, University of Turku, Turku, FI-20014, Finland
| | - Eva-Mari Aro
- Molecular Plant Biology, Department of Biochemistry, University of Turku, Turku, FI-20014, Finland
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72
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Lucker B, Schwarz E, Kuhlgert S, Ostendorf E, Kramer DM. Spectroanalysis in native gels (SING): rapid spectral analysis of pigmented thylakoid membrane complexes separated by CN-PAGE. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 92:744-756. [PMID: 28865165 DOI: 10.1111/tpj.13703] [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: 07/05/2017] [Revised: 08/22/2017] [Accepted: 08/29/2017] [Indexed: 06/07/2023]
Abstract
Photosynthetic organisms rapidly adjust the capture, transfer and utilization of light energy to optimize the efficiency of photosynthesis and avoid photodamage. These adjustments involve fine-tuning of expression levels and mutual interactions among electron/proton transfer components and their associated light-harvesting antenna. Detailed studies of these interactions and their dynamics have been hindered by the low throughput and resolution of currently available research tools, which involve laborious isolation, separation and characterization steps. To address these issues, we developed an approach that measured multiple spectroscopic properties of thylakoid preparations directly in native polyacrylamide gel electrophoresis gels, enabling unprecedented resolution of photosynthetic complexes, both in terms of the spectroscopic and functional details, as well as the ability to distinguish separate complexes and thus test their functional connections. As a demonstration, we explore the thylakoid membrane components of Chlamydomonas reinhardtii acclimated to high and low light, using a combination of room temperature absorption and 77K fluorescence emission to generate a multi-dimensional molecular and spectroscopic map of the photosynthetic apparatus. We show that low-light-acclimated cells accumulate a photosystem I-containing megacomplex that is absent in high-light-acclimated cells and contains distinct LhcII proteins that can be distinguished based on their spectral signatures.
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Affiliation(s)
- Ben Lucker
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
| | - Eliezer Schwarz
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
| | - Sebastian Kuhlgert
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
| | - Elisabeth Ostendorf
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
| | - David M Kramer
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
- DOE-Plant Research Laboratory, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
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73
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Tan T, Sun Y, Luo S, Zhang C, Zhou H, Lin H. Efficient modulation of photosynthetic apparatus confers desiccation tolerance in the resurrection plant Boea hygrometrica. PLANT & CELL PHYSIOLOGY 2017; 58:1976-1990. [PMID: 29036694 DOI: 10.1093/pcp/pcx140] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Accepted: 09/04/2017] [Indexed: 05/20/2023]
Abstract
Boea hygrometrica (B. hygrometrica) can tolerate severe desiccation and resume photosynthetic activity rapidly upon water availability. However, little is known about the mechanisms by which B. hygrometrica adapts to dehydration and resumes competence upon rehydration. Here we determine how B. hygrometrica deals with oxidative stress, excessive excitation/electron pressures as well as photosynthetic apparatus modulation during dehydration/rehydration. By measuring ROS generation and scavenging efficiency, we found that B. hygrometrica possesses efficient strategies to maintain cellular redox homeostasis. Transmission electron microscopy (TEM) analysis revealed a remarkable alteration of chloroplast architecture and plastoglobules (PGs) accumulation during dehydration/rehydration. Pulse-amplitude modulated (PAM) chlorophyll fluorescence measurements, P700 redox assay as well as chlorophyll fluorescence emission spectra analysis on leaves of B. hygrometrica during dehydration/rehydration were also performed. Results showed that the photochemical activity of PSII as well as photoprotective energy dissipation in PSII undergo gradual inactivation/activation during dehydration/rehydration in B. hygrometrica; PSI activity is relatively induced upon water deficit, and dehydration leads to physical interaction between PSI and LHCII. Furthermore, blue-native polyacrylamide gel electrophoresis (BN-PAGE) and immunoblot analysis revealed that the protein abundance of light harvesting complexes decrease markedly along with internal water deficit to restrict light absorption and attenuate electron transfer, resulting in limited light excitation and repressed photosynthesis. In contrast, many thylakoid proteins remain at a basal level even after full dehydration. Taken together, our study demonstrated that efficient modulation of cellular redox homeostasis and photosynthetic activity confers desiccation tolerance in B. hygrometrica.
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Affiliation(s)
- Tinghong Tan
- Key Laboratory of Bio-resource and Eco-environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China
| | - Yanni Sun
- Key Laboratory of Bio-resource and Eco-environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China
| | - Shishuai Luo
- Key Laboratory of Bio-resource and Eco-environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China
| | - Chao Zhang
- Key Laboratory of Bio-resource and Eco-environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China
| | - Huapeng Zhou
- Key Laboratory of Bio-resource and Eco-environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China
| | - Honghui Lin
- Key Laboratory of Bio-resource and Eco-environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China
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74
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Molotokaite E, Remelli W, Casazza AP, Zucchelli G, Polli D, Cerullo G, Santabarbara S. Trapping Dynamics in Photosystem I-Light Harvesting Complex I of Higher Plants Is Governed by the Competition Between Excited State Diffusion from Low Energy States and Photochemical Charge Separation. J Phys Chem B 2017; 121:9816-9830. [DOI: 10.1021/acs.jpcb.7b07064] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Egle Molotokaite
- Centro
Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
| | - William Remelli
- Centro
Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
| | - Anna Paola Casazza
- Istituto
di Biologia e Biotecnologia Agraria, Consiglio Nazionale delle Ricerche, Via Bassini 15a, 20133 Milano, Italy
| | - Giuseppe Zucchelli
- Centro
Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
| | - Dario Polli
- Istituto di Fotonica e Nanotecnologie del CNR, Dipartimento di Fisica, Politecnico di Milano, P.zza Leonardo
da Vinci 32, 20133 Milano, Italy
- Center
for Nano Science and Technology at Polimi, Istituto Italiano di Tecnologia, Via Giovanni Pascoli, 70/3, 20133 Milano, Italy
| | - Giulio Cerullo
- Istituto di Fotonica e Nanotecnologie del CNR, Dipartimento di Fisica, Politecnico di Milano, P.zza Leonardo
da Vinci 32, 20133 Milano, Italy
| | - Stefano Santabarbara
- Centro
Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
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75
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Mishanin VI, Trubitsin BV, Patsaeva SV, Ptushenko VV, Solovchenko AE, Tikhonov AN. Acclimation of shade-tolerant and light-resistant Tradescantia species to growth light: chlorophyll a fluorescence, electron transport, and xanthophyll content. PHOTOSYNTHESIS RESEARCH 2017; 133:87-102. [PMID: 28176042 DOI: 10.1007/s11120-017-0339-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 01/13/2017] [Indexed: 06/06/2023]
Abstract
In this study, we have compared the photosynthetic characteristics of two contrasting species of Tradescantia plants, T. fluminensis (shade-tolerant species), and T. sillamontana (light-resistant species), grown under the low light (LL, 50-125 µmol photons m-2 s-1) or high light (HL, 875-1000 µmol photons m-2 s-1) conditions during their entire growth period. For monitoring the functional state of photosynthetic apparatus (PSA), we measured chlorophyll (Chl) a emission fluorescence spectra and kinetics of light-induced changes in the heights of fluorescence peaks at 685 and 740 nm (F 685 and F 740). We also compared the light-induced oxidation of P700 and assayed the composition of carotenoids in Tradescantia leaves grown under the LL and HL conditions. The analyses of slow induction of Chl a fluorescence (SIF) uncovered different traits in the LL- and HL-grown plants of ecologically contrasting Tradescantia species, which may have potential ecophysiological significance with respect to their tolerance to HL stress. The fluorometry and EPR studies of induction events in chloroplasts in situ demonstrated that acclimation of both Tradescantia species to HL conditions promoted faster responses of their PSA as compared to LL-grown plants. Acclimation of both species to HL also caused marked changes in the leaf anatomy and carotenoid composition (an increase in Violaxanthin + Antheraxantin + Zeaxanthin and Lutein pools), suggesting enhanced photoprotective capacity of the carotenoids in the plants grown in nature under high irradiance. Collectively, the results of the present work suggest that the mechanisms of long-term PSA photoprotection in Tradescantia are based predominantly on the light-induced remodeling of pigment-protein complexes in chloroplasts.
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Affiliation(s)
- Vladimir I Mishanin
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Boris V Trubitsin
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Svetlana V Patsaeva
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Vasily V Ptushenko
- A.N. Belozersky Institute of Physical-Chemical Biology, M.V. Lomonosov Moscow State University, Moscow, 119234, Russia
- N.M. Emanuel Institute of Biochemical Physics, Moscow, 119334, Russia
| | - Alexei E Solovchenko
- Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Alexander N Tikhonov
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia.
- N.M. Emanuel Institute of Biochemical Physics, Moscow, 119334, Russia.
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76
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Allen JF. Why we need to know the structure of phosphorylated chloroplast light-harvesting complex II. PHYSIOLOGIA PLANTARUM 2017; 161:28-44. [PMID: 28393369 DOI: 10.1111/ppl.12577] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Revised: 02/27/2017] [Accepted: 03/07/2017] [Indexed: 05/11/2023]
Abstract
In oxygenic photosynthesis there are two 'light states' - adaptations of the photosynthetic apparatus to spectral composition that otherwise favours either photosystem I or photosystem II. In chloroplasts of green plants the transition to light state 2 depends on phosphorylation of apoproteins of a membrane-intrinsic antenna, the chlorophyll-a/b-binding, light-harvesting complex II (LHC II), and on the resulting redistribution of absorbed excitation energy from photosystem II to photosystem I. The transition to light state 1 reverses these events and requires a phospho-LHC II phosphatase. Current structures of LHC II reveal little about possible steric effects of phosphorylation. The surface-exposed N-terminal domain of an LHC II polypeptide contains its phosphorylation site and is disordered in its unphosphorylated form. A molecular recognition hypothesis proposes that state transitions are a consequence of movement of LHC II between binding sites on photosystems I and II. In state 1, LHC II forms part of the antenna of photosystem II. In state 2, a unique but as yet unidentified 3-D structure of phospho-LHC II may attach it instead to photosystem I. One possibility is that the LHC II N-terminus becomes ordered upon phosphorylation, adopting a local alpha-helical secondary structure that initiates changes in LHC II tertiary and quaternary structure that sever contact with photosystem II while securing contact with photosystem I. In order to understand redistribution of absorbed excitation energy in photosynthesis we need to know the structure of LHC II in its phosphorylated form, and in its complex with photosystem I.
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Affiliation(s)
- John F Allen
- Research Department of Genetics, Evolution and Environment, Darwin Building, University College London, Gower Street, London, WC1E 6BT, UK
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77
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Fristedt R, Trotta A, Suorsa M, Nilsson AK, Croce R, Aro EM, Lundin B. PSB33 sustains photosystem II D1 protein under fluctuating light conditions. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:4281-4293. [PMID: 28922769 PMCID: PMC5853261 DOI: 10.1093/jxb/erx218] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Accepted: 06/05/2017] [Indexed: 05/24/2023]
Abstract
On Earth, solar irradiance varies as the sun rises and sets over the horizon, and sunlight is thus in constant fluctuation, following a slow dark-low-high-low-dark curve. Optimal plant growth and development are dependent on the capacity of plants to acclimate and regulate photosynthesis in response to these changes of light. Little is known of regulative processes for photosynthesis during nocturnal events. The nucleus-encoded plant lineage-specific protein PSB33 has been described as stabilizing the photosystem II complex, especially under light stress conditions, and plants lacking PSB33 have a dysfunctional state transition. To clarify the localization and function of this protein, we used phenomic, biochemical and proteomics approaches in the model plant Arabidopsis. We report that PSB33 is predominantly located in non-appressed thylakoid regions and dynamically associates with a thylakoid protein complex in a light-dependent manner. Moreover, plants lacking PSB33 show an accelerated D1 protein degradation in nocturnal periods, and show severely stunted growth when challenged with fluctuating light. We further show that the function of PSB33 precedes the STN7 kinase to regulate or balance the excitation energy of photosystems I and II in fluctuating light conditions.
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Affiliation(s)
- Rikard Fristedt
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan, Amsterdam, The Netherlands
| | - Andrea Trotta
- Department of Biochemistry, Molecular Plant Biology, University of Turku, Finland
| | - Marjaana Suorsa
- Department of Biochemistry, Molecular Plant Biology, University of Turku, Finland
| | - Anders K Nilsson
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Roberta Croce
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan, Amsterdam, The Netherlands
| | - Eva-Mari Aro
- Department of Biochemistry, Molecular Plant Biology, University of Turku, Finland
| | - Björn Lundin
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
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78
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Nematov S, Casazza AP, Remelli W, Khuvondikov V, Santabarbara S. Spectral dependence of irreversible light-induced fluorescence quenching: Chlorophyll forms with maximal emission at 700-702 and 705-710nm as spectroscopic markers of conformational changes in the core complex. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2017; 1858:529-543. [PMID: 28499881 DOI: 10.1016/j.bbabio.2017.05.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 05/03/2017] [Accepted: 05/07/2017] [Indexed: 11/29/2022]
Abstract
The spectral dependence of the irreversible non-photochemical fluorescence quenching associated with photoinhibition in vitro has been comparatively investigated in thylakoid membranes, PSII enriched particles and PSII core complexes isolated from spinach. The analysis of the fluorescence emission spectra of dark-adapted and quenched samples as a function of the detection temperature in the 280-80K interval, indicates that Chlorophyll spectral forms having maximal emission in the 700-702nm and 705-710nm ranges gain relative intensity in concomitance with the establishment of irreversible light-induced quenching, acting thereby as spectroscopic markers. The relative enhancement of the 700-702nm and 705-710nm forms emission could be due either to an increase of their stoichiometric abundance or to their intrinsically low fluorescence quantum yields. These two factors, that can also coexist, need to be promoted by light-induced alterations in chromophore-protein as well as chromophore-chromophore interactions. The bands centred at about 701 and 706nm are also observed in the PSII core complex, suggesting their, at least partial, localisation in proximity to the reaction centre, and the occurrence of light-induced conformational changes in the core subunits.
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Affiliation(s)
- Sherzod Nematov
- Tashkent State Technical University, University str. 2, 100095 Tashkent, Uzbekistan
| | - Anna Paola Casazza
- Istituto di Biologia e Biotecnologia Agraria, Consiglio Nazionale delle Ricerche, Via Bassini 15a, 20133 Milano, Italy
| | - William Remelli
- Centro Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
| | | | - Stefano Santabarbara
- Centro Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy.
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79
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Nozue H, Oono K, Ichikawa Y, Tanimura S, Shirai K, Sonoike K, Nozue M, Hayashida N. Significance of structural variation in thylakoid membranes in maintaining functional photosystems during reproductive growth. PHYSIOLOGIA PLANTARUM 2017; 160:111-123. [PMID: 27859364 DOI: 10.1111/ppl.12528] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/31/2016] [Accepted: 10/24/2016] [Indexed: 06/06/2023]
Abstract
Structural variation in the stroma-grana (SG) arrangement of the thylakoid membranes, such as changes in the thickness of the grana stacks and in the ratio between grana and inter-grana thylakoid, is often observed. Broadly, such alterations are considered acclimation to changes in growth and the environment. However, the relation of thylakoid morphology to plant growth and photosynthesis remains obscure. Here, we report changes in the thylakoid during leaf development under a fixed light condition. Histological studies on the chloroplasts of fresh green Arabidopsis leaves have shown that characteristically shaped thylakoid membranes lacking the inter-grana region, referred to hereafter as isolated-grana (IG), occurred adjacent to highly ordered, large grana layers. This morphology was restored to conventional SG thylakoid membranes with the removal of bolting stems from reproductive plants. Statistical analysis showed a negative correlation between the incidences of IG-type chloroplasts in mesophyll cells and the rates of leaf growth. Fluorescence parameters calculated from pulse-amplitude modulated fluorometry measurements and CO2 assimilation data showed that the IG thylakoids had a photosynthetic ability that was equivalent to that of the SG thylakoids under moderate light. However, clear differences were observed in the chlorophyll a/b ratio. The IG thylakoids were apparently an acclimated phenotype to the internal condition of source leaves. The idea is supported by the fact that the life span of the IG thylakoids increased significantly in the later developing leaves. In conclusion, the heterogeneous state of thylakoid membranes is likely important in maintaining photosynthesis during the reproductive phase of growth.
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Affiliation(s)
- Hatsumi Nozue
- Research Center for Advanced Plant Factory (SU-PLAF), Faculty of Textile Science and Technology, Shinshu University, Nagano, 386-8567, Japan
| | - Kaori Oono
- Department of Applied Biology, Faculty of Textile Science and Technology, Shinshu University, Nagano, 386-8567, Japan
| | | | - Shun Tanimura
- Department of Applied Biology, Faculty of Textile Science and Technology, Shinshu University, Nagano, 386-8567, Japan
| | - Kana Shirai
- Research Center for Advanced Plant Factory (SU-PLAF), Faculty of Textile Science and Technology, Shinshu University, Nagano, 386-8567, Japan
| | - Kintake Sonoike
- Faculty of Education and Integrated Arts and Sciences, Waseda University, Tokyo, 162-8480, Japan
| | - Masayuki Nozue
- Research Center for Advanced Plant Factory (SU-PLAF), Faculty of Textile Science and Technology, Shinshu University, Nagano, 386-8567, Japan
- Department of Applied Biology, Faculty of Textile Science and Technology, Shinshu University, Nagano, 386-8567, Japan
| | - Nobuaki Hayashida
- Department of Applied Biology, Faculty of Textile Science and Technology, Shinshu University, Nagano, 386-8567, Japan
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80
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Kalaji HM, Schansker G, Brestic M, Bussotti F, Calatayud A, Ferroni L, Goltsev V, Guidi L, Jajoo A, Li P, Losciale P, Mishra VK, Misra AN, Nebauer SG, Pancaldi S, Penella C, Pollastrini M, Suresh K, Tambussi E, Yanniccari M, Zivcak M, Cetner MD, Samborska IA, Stirbet A, Olsovska K, Kunderlikova K, Shelonzek H, Rusinowski S, Bąba W. Frequently asked questions about chlorophyll fluorescence, the sequel. PHOTOSYNTHESIS RESEARCH 2017; 132:13-66. [PMID: 27815801 PMCID: PMC5357263 DOI: 10.1007/s11120-016-0318-y] [Citation(s) in RCA: 222] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Accepted: 10/17/2016] [Indexed: 05/20/2023]
Abstract
Using chlorophyll (Chl) a fluorescence many aspects of the photosynthetic apparatus can be studied, both in vitro and, noninvasively, in vivo. Complementary techniques can help to interpret changes in the Chl a fluorescence kinetics. Kalaji et al. (Photosynth Res 122:121-158, 2014a) addressed several questions about instruments, methods and applications based on Chl a fluorescence. Here, additional Chl a fluorescence-related topics are discussed again in a question and answer format. Examples are the effect of connectivity on photochemical quenching, the correction of F V /F M values for PSI fluorescence, the energy partitioning concept, the interpretation of the complementary area, probing the donor side of PSII, the assignment of bands of 77 K fluorescence emission spectra to fluorescence emitters, the relationship between prompt and delayed fluorescence, potential problems when sampling tree canopies, the use of fluorescence parameters in QTL studies, the use of Chl a fluorescence in biosensor applications and the application of neural network approaches for the analysis of fluorescence measurements. The answers draw on knowledge from different Chl a fluorescence analysis domains, yielding in several cases new insights.
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Affiliation(s)
- Hazem M. Kalaji
- Department of Plant Physiology, Faculty of Agriculture and Biology, Warsaw University of Life Sciences – SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland
| | | | - Marian Brestic
- Department of Plant Physiology, Slovak Agricultural University, Tr. A. Hlinku 2, 949 76 Nitra, Slovak Republic
| | - Filippo Bussotti
- Department of Agricultural, Food and Environmental Sciences, University of Florence, Piazzale delle Cascine 28, 50144 Florence, Italy
| | - Angeles Calatayud
- Departamento de Horticultura, Instituto Valenciano de Investigaciones Agrarias, Ctra. Moncada-Náquera Km 4.5., 46113 Moncada, Valencia Spain
| | - Lorenzo Ferroni
- Department of Life Sciences and Biotechnology, University of Ferrara, Corso Ercole I d’Este, 32, 44121 Ferrara, Italy
| | - Vasilij Goltsev
- Department of Biophysics and Radiobiology, Faculty of Biology, St. Kliment Ohridski University of Sofia, 8 Dr.Tzankov Blvd., 1164 Sofia, Bulgaria
| | - Lucia Guidi
- Department of Agriculture, Food and Environment, Via del Borghetto, 80, 56124 Pisa, Italy
| | - Anjana Jajoo
- School of Life Sciences, Devi Ahilya University, Indore, M.P. 452 001 India
| | - Pengmin Li
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling, 712100 Shaanxi China
| | - Pasquale Losciale
- Consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria [Research Unit for Agriculture in Dry Environments], 70125 Bari, Italy
| | - Vinod K. Mishra
- Department of Biotechnology, Doon (P.G.) College of Agriculture Science, Dehradun, Uttarakhand 248001 India
| | - Amarendra N. Misra
- Centre for Life Sciences, Central University of Jharkhand, Ratu-Lohardaga Road, Ranchi, 835205 India
| | - Sergio G. Nebauer
- Departamento de Producción vegetal, Universitat Politècnica de València, Camino de Vera sn., 46022 Valencia, Spain
| | - Simonetta Pancaldi
- Department of Life Sciences and Biotechnology, University of Ferrara, Corso Ercole I d’Este, 32, 44121 Ferrara, Italy
| | - Consuelo Penella
- Departamento de Horticultura, Instituto Valenciano de Investigaciones Agrarias, Ctra. Moncada-Náquera Km 4.5., 46113 Moncada, Valencia Spain
| | - Martina Pollastrini
- Department of Agricultural, Food and Environmental Sciences, University of Florence, Piazzale delle Cascine 28, 50144 Florence, Italy
| | - Kancherla Suresh
- ICAR – Indian Institute of Oil Palm Research, Pedavegi, West Godavari Dt., Andhra Pradesh 534 450 India
| | - Eduardo Tambussi
- Institute of Plant Physiology, INFIVE (Universidad Nacional de La Plata — Consejo Nacional de Investigaciones Científicas y Técnicas), Diagonal 113 N°495, CC 327, La Plata, Argentina
| | - Marcos Yanniccari
- Institute of Plant Physiology, INFIVE (Universidad Nacional de La Plata — Consejo Nacional de Investigaciones Científicas y Técnicas), Diagonal 113 N°495, CC 327, La Plata, Argentina
| | - Marek Zivcak
- Department of Plant Physiology, Slovak Agricultural University, Tr. A. Hlinku 2, 949 76 Nitra, Slovak Republic
| | - Magdalena D. Cetner
- Department of Plant Physiology, Faculty of Agriculture and Biology, Warsaw University of Life Sciences – SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland
| | - Izabela A. Samborska
- Department of Plant Physiology, Faculty of Agriculture and Biology, Warsaw University of Life Sciences – SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland
| | | | - Katarina Olsovska
- Department of Plant Physiology, Slovak University of Agriculture, A. Hlinku 2, 94976 Nitra, Slovak Republic
| | - Kristyna Kunderlikova
- Department of Plant Physiology, Slovak University of Agriculture, A. Hlinku 2, 94976 Nitra, Slovak Republic
| | - Henry Shelonzek
- Department of Plant Anatomy and Cytology, Faculty of Biology and Environmental Protection, University of Silesia, ul. Jagiellońska 28, 40-032 Katowice, Poland
| | - Szymon Rusinowski
- Institute for Ecology of Industrial Areas, Kossutha 6, 40-844 Katowice, Poland
| | - Wojciech Bąba
- Department of Plant Ecology, Institute of Botany, Jagiellonian University, Lubicz 46, 31-512 Kraków, Poland
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81
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Wientjes E, Philippi J, Borst JW, van Amerongen H. Imaging the Photosystem I/Photosystem II chlorophyll ratio inside the leaf. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2017; 1858:259-265. [DOI: 10.1016/j.bbabio.2017.01.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 01/10/2017] [Accepted: 01/13/2017] [Indexed: 02/03/2023]
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82
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Bos I, Bland KM, Tian L, Croce R, Frankel LK, van Amerongen H, Bricker TM, Wientjes E. Multiple LHCII antennae can transfer energy efficiently to a single Photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2017; 1858:371-378. [PMID: 28237494 DOI: 10.1016/j.bbabio.2017.02.012] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 02/20/2017] [Accepted: 02/21/2017] [Indexed: 01/31/2023]
Abstract
Photosystems I and II (PSI and PSII) work in series to drive oxygenic photosynthesis. The two photosystems have different absorption spectra, therefore changes in light quality can lead to imbalanced excitation of the photosystems and a loss in photosynthetic efficiency. In a short-term adaptation response termed state transitions, excitation energy is directed to the light-limited photosystem. In higher plants a special pool of LHCII antennae, which can be associated with either PSI or PSII, participates in these state transitions. It is known that one LHCII antenna can associate with the PsaH site of PSI. However, membrane fractions were recently isolated in which multiple LHCII antennae appear to transfer energy to PSI. We have used time-resolved fluorescence-streak camera measurements to investigate the energy transfer rates and efficiency in these membrane fractions. Our data show that energy transfer from LHCII to PSI is relatively slow. Nevertheless, the trapping efficiency in supercomplexes of PSI with ~2.4 LHCIIs attached is 94%. The absorption cross section of PSI can thus be increased with ~65% without having significant loss in quantum efficiency. Comparison of the fluorescence dynamics of PSI-LHCII complexes, isolated in a detergent or located in their native membrane environment, indicates that the environment influences the excitation energy transfer rates in these complexes. This demonstrates the importance of studying membrane protein complexes in their natural environment.
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Affiliation(s)
- Inge Bos
- Laboratory of Biophysics, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands
| | - Kaitlyn M Bland
- Department of Biological Sciences, Biochemistry and Molecular Biology Section, Louisiana State University, Baton Rouge, LA 70803, United States
| | - Lijin Tian
- Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Roberta Croce
- Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Laurie K Frankel
- Department of Biological Sciences, Biochemistry and Molecular Biology Section, Louisiana State University, Baton Rouge, LA 70803, United States
| | - Herbert van Amerongen
- Laboratory of Biophysics, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands; MicroSpectroscopy Centre, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands
| | - Terry M Bricker
- Department of Biological Sciences, Biochemistry and Molecular Biology Section, Louisiana State University, Baton Rouge, LA 70803, United States
| | - Emilie Wientjes
- Laboratory of Biophysics, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands.
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83
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MURAKAMI K, MATSUDA R, FUJIWARA K. A Basis for Selecting Light Spectral Distribution for Evaluating Leaf Photosynthetic Rates of Plants Grown under Different Light Spectral Distributions. ACTA ACUST UNITED AC 2017. [DOI: 10.2525/ecb.55.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Keach MURAKAMI
- Graduate School of Agricultural and Life Sciences, The University of Tokyo
| | - Ryo MATSUDA
- Graduate School of Agricultural and Life Sciences, The University of Tokyo
| | - Kazuhiro FUJIWARA
- Graduate School of Agricultural and Life Sciences, The University of Tokyo
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84
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Marutani Y, Yamauchi Y, Higashiyama M, Miyoshi A, Akimoto S, Inoue K, Ikeda KI, Mizutani M, Sugimoto Y. Essential role of the PSI-LHCII supercomplex in photosystem acclimation to light and/or heat conditions by state transitions. PHOTOSYNTHESIS RESEARCH 2017; 131:41-50. [PMID: 27432175 DOI: 10.1007/s11120-016-0295-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 07/11/2016] [Indexed: 05/22/2023]
Abstract
Light and temperature affect state transitions through changes in the plastoquinone (PQ) redox state in photosynthetic organisms. We demonstrated that light and/or heat treatment induced preferential photosystem (PS) I excitation by binding light-harvesting complex II (LHCII) proteins. The photosystem of wheat was in state 1 after dark overnight treatment, wherein PQ was oxidized and most of LHCII was not bound to PSI. At the onset of the light treatment [25 °C in the light (100 µmol photons m-2 s-1)], two major LHCIIs, Lhcb1 and Lhcb2 were phosphorylated, and the PSI-LHCII supercomplex formed within 5 min, which coincided with an increase in the PQ oxidation rate. Heat treatment at 40 °C of light-adapted wheat led to further LHCII protein phosphorylation of, resultant cyclic electron flow promotion, which was accompanied by ultrafast excitation of PSI and structural changes of thylakoid membranes, thereby protecting PSII from heat damage. These results suggest that LHCIIs are required for the functionality of wheat plant PSI, as it keeps PQ oxidized by regulating photochemical electron flow, thereby helping acclimation to environmental changes.
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Affiliation(s)
- Yoko Marutani
- Graduate School of Agricultural Science, Kobe University, Nada-ku, Kobe, 657-8501, Japan
- Technology Innovation Center, Sumika Chemical Analysis Service, Ltd., 3-1-135, Kasugade-naka, Konohana-ku, Osaka, 554-0022, Japan
| | - Yasuo Yamauchi
- Graduate School of Agricultural Science, Kobe University, Nada-ku, Kobe, 657-8501, Japan.
| | - Mari Higashiyama
- Graduate School of Agricultural Science, Kobe University, Nada-ku, Kobe, 657-8501, Japan
| | - Akihito Miyoshi
- Faculty of Agriculture, Kobe University, Nada-ku, Kobe, 657-8501, Japan
| | - Seiji Akimoto
- Molecular Photoscience Research Center, Kobe University, Nada-ku, Kobe, 657-8501, Japan
| | - Kanako Inoue
- Graduate School of Agricultural Science, Kobe University, Nada-ku, Kobe, 657-8501, Japan
- Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, Ibaraki, Osaka, 567-0047, Japan
| | - Ken-Ichi Ikeda
- Graduate School of Agricultural Science, Kobe University, Nada-ku, Kobe, 657-8501, Japan
| | - Masaharu Mizutani
- Graduate School of Agricultural Science, Kobe University, Nada-ku, Kobe, 657-8501, Japan
| | - Yukihiro Sugimoto
- Graduate School of Agricultural Science, Kobe University, Nada-ku, Kobe, 657-8501, Japan
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85
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Murakami K, Matsuda R, Fujiwara K. Interaction between the spectral photon flux density distributions of light during growth and for measurements in net photosynthetic rates of cucumber leaves. PHYSIOLOGIA PLANTARUM 2016; 158:213-24. [PMID: 26822286 DOI: 10.1111/ppl.12421] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 12/03/2015] [Accepted: 12/14/2015] [Indexed: 05/09/2023]
Abstract
The net photosynthetic rate of a leaf becomes acclimated to the plant's environment during growth. These rates are often measured, evaluated and compared among leaves of plants grown under different light conditions. In this study, we compared net photosynthetic rates of cucumber leaves grown under white light-emitting diode (LED) light without and with supplemental far-red (FR) LED light (W- and WFR-leaves, respectively) under three different measuring light (ML) conditions: their respective growth light (GL), artificial sunlight (AS) and blue and red (BR) light. The difference in the measured photosynthetic rates between W- and WFR-leaves was greater under BR than under GL and AS. In other words, an interaction between supplemental FR light during growth and the spectral photon flux density distribution (SPD) of ML affected the measured net photosynthetic rates. We showed that the comparison and evaluation of leaf photosynthetic rates and characteristics can be biased depending on the SPD of ML, especially for plants grown under different photon flux densities in the FR waveband. We also investigated the mechanism of the interaction. We confirmed that the distribution of excitation energy between the two photosystems (PSs) changed in response to the SPD of GL, and that this change resulted in the interaction, as suggested in previous reports. However, changes in PS stoichiometry could not completely explain the adjustment in excitation energy distribution observed in this study, suggesting that other mechanisms may be involved in the interaction.
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Affiliation(s)
- Keach Murakami
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo, Tokyo, 113-8657, Japan.
| | - Ryo Matsuda
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo, Tokyo, 113-8657, Japan
| | - Kazuhiro Fujiwara
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo, Tokyo, 113-8657, Japan
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86
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Fan S, Zhang D, Lei C, Chen H, Xing L, Ma J, Zhao C, Han M. Proteome Analyses Using iTRAQ Labeling Reveal Critical Mechanisms in Alternate Bearing Malus prunifolia. J Proteome Res 2016; 15:3602-3616. [DOI: 10.1021/acs.jproteome.6b00357] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Sheng Fan
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Dong Zhang
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Chao Lei
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Hongfei Chen
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Libo Xing
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Juanjuan Ma
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Caiping Zhao
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Mingyu Han
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
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87
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Trotta A, Suorsa M, Rantala M, Lundin B, Aro EM. Serine and threonine residues of plant STN7 kinase are differentially phosphorylated upon changing light conditions and specifically influence the activity and stability of the kinase. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 87:484-94. [PMID: 27214592 DOI: 10.1111/tpj.13213] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 05/04/2016] [Accepted: 05/09/2016] [Indexed: 05/22/2023]
Abstract
STN7 kinase catalyzes the phosphorylation of the globally most common membrane proteins, the light-harvesting complex II (LHCII) in plant chloroplasts. STN7 itself possesses one serine (Ser) and two threonine (Thr) phosphosites. We show that phosphorylation of the Thr residues protects STN7 against degradation in darkness, low light and red light, whereas increasing light intensity and far red illumination decrease phosphorylation and induce STN7 degradation. Ser phosphorylation, in turn, occurs under red and low intensity white light, coinciding with the client protein (LHCII) phosphorylation. Through analysis of the counteracting LHCII phosphatase mutant tap38/pph1, we show that Ser phosphorylation and activation of the STN7 kinase for subsequent LHCII phosphorylation are heavily affected by pre-illumination conditions. Transitions between the three activity states of the STN7 kinase (deactivated in darkness and far red light, activated in low and red light, inhibited in high light) are shown to modulate the phosphorylation of the STN7 Ser and Thr residues independently of each other. Such dynamic regulation of STN7 kinase phosphorylation is crucial for plant growth and environmental acclimation.
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Affiliation(s)
- Andrea Trotta
- Molecular Plant Biology, Department of Biochemistry, University of Turku, Turku, FI-20520, Finland
| | - Marjaana Suorsa
- Molecular Plant Biology, Department of Biochemistry, University of Turku, Turku, FI-20520, Finland
| | - Marjaana Rantala
- Molecular Plant Biology, Department of Biochemistry, University of Turku, Turku, FI-20520, Finland
| | - Björn Lundin
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, 405 30, Sweden
| | - Eva-Mari Aro
- Molecular Plant Biology, Department of Biochemistry, University of Turku, Turku, FI-20520, Finland.
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88
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Bressan M, Dall'Osto L, Bargigia I, Alcocer MJP, Viola D, Cerullo G, D'Andrea C, Bassi R, Ballottari M. LHCII can substitute for LHCI as an antenna for photosystem I but with reduced light-harvesting capacity. NATURE PLANTS 2016; 2:16131. [PMID: 27564313 DOI: 10.1038/nplants.2016.131] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 07/28/2016] [Indexed: 05/10/2023]
Abstract
Light-harvesting complexes (LHCs) are major constituents of the antenna systems in higher plant photosystems. Four Lhca subunits are tightly bound to the photosystem I (PSI) core complex, forming its outer antenna moiety called LHCI. The Arabidopsis thaliana mutant ΔLhca lacks all Lhca1-4 subunits and compensates for its decreased antenna size by binding LHCII trimers, the main constituent of the photosystem II antenna system, to PSI. In this work we have investigated the effect of LHCI/LHCII substitution by comparing the light harvesting and excitation energy transfer efficiency properties of PSI complexes isolated from ΔLhca mutants and from the wild type, as well as the consequences for plant growth. We show that the excitation energy transfer efficiency was not compromised by the substitution of LHCI with LHCII but a significant reduction in the absorption cross-section was observed. The absence of LHCI subunits in PSI thus significantly limits light harvesting, even on LHCII binding, inducing, as a consequence, a strong reduction in growth.
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Affiliation(s)
- Mauro Bressan
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, I-37134 Verona, Italy
| | - Luca Dall'Osto
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, I-37134 Verona, Italy
| | - Ilaria Bargigia
- Centre for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, via Pascoli 70/3, 20133 Milan, Italy
| | - Marcelo J P Alcocer
- Centre for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, via Pascoli 70/3, 20133 Milan, Italy
- IFN-CNR, Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy
| | - Daniele Viola
- IFN-CNR, Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy
| | - Giulio Cerullo
- IFN-CNR, Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy
| | - Cosimo D'Andrea
- Centre for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, via Pascoli 70/3, 20133 Milan, Italy
- IFN-CNR, Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy
| | - Roberto Bassi
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, I-37134 Verona, Italy
| | - Matteo Ballottari
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, I-37134 Verona, Italy
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89
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Ferroni L, Suorsa M, Aro EM, Baldisserotto C, Pancaldi S. Light acclimation in the lycophyte Selaginella martensii depends on changes in the amount of photosystems and on the flexibility of the light-harvesting complex II antenna association with both photosystems. THE NEW PHYTOLOGIST 2016; 211:554-68. [PMID: 27058989 DOI: 10.1111/nph.13939] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 02/20/2016] [Indexed: 05/22/2023]
Abstract
Vascular plants have evolved a long-term light acclimation strategy primarily relying on the regulation of the relative amounts of light-harvesting complex II (LHCII) and of the two photosystems, photosystem I (PSI) and photosystem II (PSII). We investigated whether such a model is also valid in Selaginella martensii, a species belonging to the early diverging group of lycophytes. Selaginella martensii plants were acclimated to three natural light regimes (extremely low light (L), medium light (M) and full sunlight (H)) and thylakoid organization was characterized combining ultrastructural, biochemical and functional methods. From L to H plants, thylakoid architecture was rearranged from (pseudo)lamellar to predominantly granal, the PSII : PSI ratio changed in favour of PSI, and the photochemical capacity increased. However, regulation of light harvesting did not occur through variations in the amount of free LHCII, but rather resulted from the flexibility of the association of free LHCII with PSII and PSI. In lycophytes, the free interspersed LHCII serves a fixed proportion of reaction centres, either PSII or PSI, and the regulation of PSI-LHCII(-PSII) megacomplexes is an integral part of long-term acclimation. Free LHCII ensures photoprotection of PSII, allows regulated use of PSI as an energy quencher, and can also quench endangered PSI.
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Affiliation(s)
- Lorenzo Ferroni
- Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este 32, 44121, Ferrara, Italy
| | - Marjaana Suorsa
- Department of Biochemistry, Molecular Plant Biology, University of Turku, FI-20014, Turku, Finland
| | - Eva-Mari Aro
- Department of Biochemistry, Molecular Plant Biology, University of Turku, FI-20014, Turku, Finland
| | - Costanza Baldisserotto
- Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este 32, 44121, Ferrara, Italy
| | - Simonetta Pancaldi
- Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este 32, 44121, Ferrara, Italy
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90
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Grieco M, Jain A, Ebersberger I, Teige M. An evolutionary view on thylakoid protein phosphorylation uncovers novel phosphorylation hotspots with potential functional implications. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:3883-96. [PMID: 27117338 DOI: 10.1093/jxb/erw164] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The regulation of photosynthetic light reactions by reversible protein phosphorylation is well established today, but functional studies have so far mostly been restricted to processes affecting light-harvesting complex II and the core proteins of photosystem II. Virtually no functional data are available on regulatory effects at the other photosynthetic complexes despite the identification of multiple phosphorylation sites. Therefore we summarize the available data from 50 published phospho-proteomics studies covering the main complexes involved in photosynthetic light reactions in the 'green lineage' (i.e. green algae and land plants) as well as its cyanobacterial counterparts. In addition, we performed an extensive orthologue search for the major photosynthetic thylakoid proteins in 41 sequenced genomes and generated sequence alignments to survey the phylogenetic distribution of phosphorylation sites and their evolutionary conservation from green algae to higher plants. We observed a number of uncharacterized phosphorylation hotspots at photosystem I and the ATP synthase with potential functional relevance as well as an unexpected divergence of phosphosites. Although technical limitations might account for a number of those differences, we think that many of these phosphosites have important functions. This is particularly important for mono- and dicot plants, where these sites might be involved in regulatory processes such as stress acclimation.
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Affiliation(s)
- Michele Grieco
- Department of Ecogenomics and Systems Biology, University of Vienna, Althanstr. 14, A-1090 Vienna, Austria
| | - Arpit Jain
- Department for Applied Bioinformatics, Institute for Cell Biology and Neuroscience, Goethe University, Max-von-Laue Str. 13, D-60438 Frankfurt, Germany
| | - Ingo Ebersberger
- Department for Applied Bioinformatics, Institute for Cell Biology and Neuroscience, Goethe University, Max-von-Laue Str. 13, D-60438 Frankfurt, Germany Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberg Anlage 25, D-60325 Frankfurt, Germany
| | - Markus Teige
- Department of Ecogenomics and Systems Biology, University of Vienna, Althanstr. 14, A-1090 Vienna, Austria
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91
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Nakajima Munekage Y. Light harvesting and chloroplast electron transport in NADP-malic enzyme type C4 plants. CURRENT OPINION IN PLANT BIOLOGY 2016; 31:9-15. [PMID: 26999307 DOI: 10.1016/j.pbi.2016.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 02/17/2016] [Accepted: 03/01/2016] [Indexed: 06/05/2023]
Abstract
The structure of thylakoids in chloroplasts and the organization of the electron transport chain changed dynamically during the evolution of C4 photosynthesis, especially in the nicotinamide adenine dinucleotide phosphate (NADP)-malic enzyme type C4 species. Stacked grana membranes are strongly reduced in the bundle sheath chloroplasts of these plants, where photosystem II activity is diminished and cyclic electron transport around photosystem I mainly occurs. This change optimizes the ATP/NADPH production ratio in bundle sheath chloroplasts to drive the metabolic cycle of C4 photosynthesis. This review summarizes the current model of light harvesting and electron transport in the NADP-malic enzyme type C4 plants and discusses how it changed during the evolution of C4 photosynthesis.
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Affiliation(s)
- Yuri Nakajima Munekage
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan.
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92
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Iermak I, Vink J, Bader AN, Wientjes E, van Amerongen H. Visualizing heterogeneity of photosynthetic properties of plant leaves with two-photon fluorescence lifetime imaging microscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1473-1478. [PMID: 27239747 DOI: 10.1016/j.bbabio.2016.05.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 05/09/2016] [Accepted: 05/21/2016] [Indexed: 01/09/2023]
Abstract
Two-photon fluorescence lifetime imaging microscopy (FLIM) was used to analyse the distribution and properties of Photosystem I (PSI) and Photosystem II (PSII) in palisade and spongy chloroplasts of leaves from the C3 plant Arabidopsis thaliana and the C4 plant Miscanthus x giganteus. This was achieved by separating the time-resolved fluorescence of PSI and PSII in the leaf. It is found that the PSII antenna size is larger on the abaxial side of A. thaliana leaves, presumably because chloroplasts in the spongy mesophyll are "shaded" by the palisade cells. The number of chlorophylls in PSI on the adaxial side of the A. thaliana leaf is slightly higher. The C4 plant M. x giganteus contains both mesophyll and bundle sheath cells, which have a different PSI/PSII ratio. It is shown that the time-resolved fluorescence of bundle sheath and mesophyll cells can be analysed separately. The relative number of chlorophylls, which belong to PSI (as compared to PSII) in the bundle sheath cells is at least 2.5 times higher than in mesophyll cells. FLIM is thus demonstrated to be a useful technique to study the PSI/PSII ratio and PSII antenna size in well-defined regions of plant leaves without having to isolate pigment-protein complexes.
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Affiliation(s)
- Ievgeniia Iermak
- Laboratory of Biophysics, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands; BioSolar Cells Project Office, P.O. Box 98, 6700 AB Wageningen, The Netherlands
| | - Jochem Vink
- Laboratory of Biophysics, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands
| | - Arjen N Bader
- Laboratory of Biophysics, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands; MicroSpectroscopy Centre, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands
| | - Emilie Wientjes
- Laboratory of Biophysics, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands
| | - Herbert van Amerongen
- Laboratory of Biophysics, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands; BioSolar Cells Project Office, P.O. Box 98, 6700 AB Wageningen, The Netherlands; MicroSpectroscopy Centre, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands
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93
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Farooq S, Chmeliov J, Trinkunas G, Valkunas L, van Amerongen H. Is There Excitation Energy Transfer between Different Layers of Stacked Photosystem-II-Containing Thylakoid Membranes? J Phys Chem Lett 2016; 7:1406-1410. [PMID: 27014831 DOI: 10.1021/acs.jpclett.6b00474] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We have compared picosecond fluorescence decay kinetics for stacked and unstacked photosystem II membranes in order to evaluate the efficiency of excitation energy transfer between the neighboring layers. The measured kinetics were analyzed in terms of a recently developed fluctuating antenna model that provides information about the dimensionality of the studied system. Independently of the stacking state, all preparations exhibited virtually the same value of the apparent dimensionality, d = 1.6. Thus, we conclude that membrane stacking does not affect the efficiency of the delivery of excitation energy toward the reaction centers but ensures a more compact organization of the thylakoid membranes within the chloroplast and separation of photosystems I and II.
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Affiliation(s)
- Shazia Farooq
- Laboratory of Biophysics, Wageningen University , P.O. Box 8128, 6700 ET Wageningen, The Netherlands
| | - Jevgenij Chmeliov
- Department of Theoretical Physics, Faculty of Physics, Vilnius University , Saulėtekio Avenue 9, 10222 Vilnius, Lithuania
- Department of Molecular Compound Physics, Institute of Physics, Center for Physical Sciences and Technology , Goštauto 11, 01108 Vilnius, Lithuania
| | - Gediminas Trinkunas
- Department of Theoretical Physics, Faculty of Physics, Vilnius University , Saulėtekio Avenue 9, 10222 Vilnius, Lithuania
- Department of Molecular Compound Physics, Institute of Physics, Center for Physical Sciences and Technology , Goštauto 11, 01108 Vilnius, Lithuania
| | - Leonas Valkunas
- Department of Theoretical Physics, Faculty of Physics, Vilnius University , Saulėtekio Avenue 9, 10222 Vilnius, Lithuania
- Department of Molecular Compound Physics, Institute of Physics, Center for Physical Sciences and Technology , Goštauto 11, 01108 Vilnius, Lithuania
| | - Herbert van Amerongen
- Laboratory of Biophysics, Wageningen University , P.O. Box 8128, 6700 ET Wageningen, The Netherlands
- MicroSpectroscopy Centre, Wageningen University , P.O. Box 8128, 6700 ET Wageningen, The Netherlands
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94
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Akhtar P, Lingvay M, Kiss T, Deák R, Bóta A, Ughy B, Garab G, Lambrev PH. Excitation energy transfer between Light-harvesting complex II and Photosystem I in reconstituted membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:462-72. [DOI: 10.1016/j.bbabio.2016.01.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 01/22/2016] [Accepted: 01/27/2016] [Indexed: 12/01/2022]
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95
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Liu W, Tu W, Liu Y, Sun R, Liu C, Yang C. The N-terminal domain of Lhcb proteins is critical for recognition of the LHCII kinase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:79-88. [DOI: 10.1016/j.bbabio.2015.10.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 10/06/2015] [Accepted: 10/11/2015] [Indexed: 12/14/2022]
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96
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97
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Chmeliov J, Trinkunas G, van Amerongen H, Valkunas L. Excitation migration in fluctuating light-harvesting antenna systems. PHOTOSYNTHESIS RESEARCH 2016; 127:49-60. [PMID: 25605669 DOI: 10.1007/s11120-015-0083-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 01/07/2015] [Indexed: 06/04/2023]
Abstract
Complex multi-exponential fluorescence decay kinetics observed in various photosynthetic systems like photosystem II (PSII) have often been explained by the reversible quenching mechanism of the charge separation taking place in the reaction center (RC) of PSII. However, this description does not account for the intrinsic dynamic disorder of the light-harvesting proteins as well as their fluctuating dislocations within the antenna, which also facilitate the repair of RCs, state transitions, and the process of non-photochemical quenching. Since dynamic fluctuations result in varying connectivity between pigment-protein complexes, they can also lead to non-exponential excitation decay kinetics. Based on this presumption, we have recently proposed a simple conceptual model describing excitation diffusion in a continuous medium and accounting for possible variations of the excitation transfer pathways. In the current work, this model is further developed and then applied to describe fluorescence kinetics originating from very diverse antenna systems, ranging from PSII of various sizes to LHCII aggregates and even the entire thylakoid membrane. In all cases, complex multi-exponential fluorescence kinetics are perfectly reproduced on the entire relevant time scale without assuming any radical pair equilibration at the side of the excitation quencher, but using just a few parameters reflecting the mean excitation energy transfer rate as well as the overall average organization of the photosynthetic antenna.
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Affiliation(s)
- Jevgenij Chmeliov
- Department of Theoretical Physics, Faculty of Physics, Vilnius University, Saulėtekio Ave. 9, 10222, Vilnius, Lithuania
- Institute of Physics, Center for Physical Sciences and Technology, Gostauto 11, 01108, Vilnius, Lithuania
| | - Gediminas Trinkunas
- Department of Theoretical Physics, Faculty of Physics, Vilnius University, Saulėtekio Ave. 9, 10222, Vilnius, Lithuania
- Institute of Physics, Center for Physical Sciences and Technology, Gostauto 11, 01108, Vilnius, Lithuania
| | - Herbert van Amerongen
- Laboratory of Biophysics, Wageningen University, P.O. Box 8128, 6700, Wageningen, The Netherlands
| | - Leonas Valkunas
- Department of Theoretical Physics, Faculty of Physics, Vilnius University, Saulėtekio Ave. 9, 10222, Vilnius, Lithuania.
- Institute of Physics, Center for Physical Sciences and Technology, Gostauto 11, 01108, Vilnius, Lithuania.
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98
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Novoderezhkin VI, Croce R, Wahadoszamen M, Polukhina I, Romero E, van Grondelle R. Mixing of exciton and charge-transfer states in light-harvesting complex Lhca4. Phys Chem Chem Phys 2016; 18:19368-77. [DOI: 10.1039/c6cp02225a] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Structure-based modeling of spectra of the wild-type Lhca4 and NH mutant enables us to build the exciton model of the complex that includes a charge-transfer state mixed with the excited-state manifold.
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Affiliation(s)
| | - Roberta Croce
- Department of Biophysics
- Faculty of Sciences
- VU University Amsterdam
- 1081 HV Amsterdam
- The Netherlands
| | - Md. Wahadoszamen
- Department of Biophysics
- Faculty of Sciences
- VU University Amsterdam
- 1081 HV Amsterdam
- The Netherlands
| | - Iryna Polukhina
- Department of Biophysics
- Faculty of Sciences
- VU University Amsterdam
- 1081 HV Amsterdam
- The Netherlands
| | - Elisabet Romero
- Department of Biophysics
- Faculty of Sciences
- VU University Amsterdam
- 1081 HV Amsterdam
- The Netherlands
| | - Rienk van Grondelle
- Department of Biophysics
- Faculty of Sciences
- VU University Amsterdam
- 1081 HV Amsterdam
- The Netherlands
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99
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Bielczynski LW, Schansker G, Croce R. Effect of Light Acclimation on the Organization of Photosystem II Super- and Sub-Complexes in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2016; 7:105. [PMID: 26925068 PMCID: PMC4756287 DOI: 10.3389/fpls.2016.00105] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 01/20/2016] [Indexed: 05/18/2023]
Abstract
To survive under highly variable environmental conditions, higher plants have acquired a large variety of acclimation responses. Different strategies are used to cope with changes in light intensity with the common goal of modulating the functional antenna size of Photosystem II (PSII). Here we use a combination of biochemical and biophysical methods to study these changes in response to acclimation to high light (HL). After 2 h of exposure, a decrease in the amount of the large PSII supercomplexes is observed indicating that plants are already acclimating to HL at this stage. It is also shown that in HL the relative amount of antenna proteins decreases but this decrease is far less than the observed decrease of the functional antenna size, suggesting that part of the antenna present in the membranes in HL does not transfer energy efficiently to the reaction center. Finally, we observed LHCII monomers in all conditions. As the solubilization conditions used do not lead to monomerization of purified LHCII trimers, we should conclude that a population of LHCII monomers exists in the membrane. The relative amount of LHCII monomers strongly increases in plants acclimated to HL, while no changes in the trimer to monomer ratio are observed upon short exposure to stress.
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100
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Sato R, Ito H, Tanaka A. Chlorophyll b degradation by chlorophyll b reductase under high-light conditions. PHOTOSYNTHESIS RESEARCH 2015; 126:249-59. [PMID: 25896488 DOI: 10.1007/s11120-015-0145-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 04/09/2015] [Indexed: 05/03/2023]
Abstract
The light-harvesting chlorophyll a/b binding protein complex of photosystem II (LHCII) is the main antenna complex of photosystem II (PSII). Plants change their LHCII content depending on the light environment. Under high-light conditions, the content of LHCII should decrease because over-excitation damages the photosystem. Chlorophyll b is indispensable for accumulating LHCII, and chlorophyll b degradation induces LHCII degradation. Chlorophyll b degradation is initiated by chlorophyll b reductase (CBR). In land plants, NON-YELLOW COLORING 1 (NYC1) and NYC1-Like (NOL) are isozymes of CBR. We analyzed these mutants to determine their functions under high-light conditions. During high-light treatment, the chlorophyll a/b ratio was stable in the wild-type (WT) and nol plants, and the LHCII content decreased in WT plants. The chlorophyll a/b ratio decreased in the nyc1 and nyc1/nol plants, and a substantial degree of LHCII was retained in nyc1/nol plants after the high-light treatment. These results demonstrate that NYC1 degrades the chlorophyll b on LHCII under high-light conditions, thus decreasing the LHCII content. After the high-light treatment, the maximum quantum efficiency of the PSII photochemistry was lower in nyc1 and nyc1/nol plants than in WT and nol plants. A larger light-harvesting system would damage PSII in nyc1 and nyc1/nol plants. The fluorescence spectroscopy of the leaves indicated that photosystem I was also damaged by the excess LHCII in nyc1/nol plants. These observations suggest that chlorophyll b degradation by NYC1 is the initial reaction for the optimization of the light-harvesting capacity under high-light conditions.
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Affiliation(s)
- Rei Sato
- Institute of Low Temperature Science, Hokkaido University, N19 W8, Kita-ku, Sapporo, 060-0819, Japan
| | - Hisashi Ito
- Institute of Low Temperature Science, Hokkaido University, N19 W8, Kita-ku, Sapporo, 060-0819, Japan.
- CREST, Japan Science and Technology Agency, N19 W8, Kita-ku, Sapporo, 060-0819, Japan.
| | - Ayumi Tanaka
- Institute of Low Temperature Science, Hokkaido University, N19 W8, Kita-ku, Sapporo, 060-0819, Japan
- CREST, Japan Science and Technology Agency, N19 W8, Kita-ku, Sapporo, 060-0819, Japan
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