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Fu P, Montes CM, Siebers MH, Gomez-Casanovas N, McGrath JM, Ainsworth EA, Bernacchi CJ. Advances in field-based high-throughput photosynthetic phenotyping. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:3157-3172. [PMID: 35218184 PMCID: PMC9126737 DOI: 10.1093/jxb/erac077] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 02/23/2022] [Indexed: 05/22/2023]
Abstract
Gas exchange techniques revolutionized plant research and advanced understanding, including associated fluxes and efficiencies, of photosynthesis, photorespiration, and respiration of plants from cellular to ecosystem scales. These techniques remain the gold standard for inferring photosynthetic rates and underlying physiology/biochemistry, although their utility for high-throughput phenotyping (HTP) of photosynthesis is limited both by the number of gas exchange systems available and the number of personnel available to operate the equipment. Remote sensing techniques have long been used to assess ecosystem productivity at coarse spatial and temporal resolutions, and advances in sensor technology coupled with advanced statistical techniques are expanding remote sensing tools to finer spatial scales and increasing the number and complexity of phenotypes that can be extracted. In this review, we outline the photosynthetic phenotypes of interest to the plant science community and describe the advances in high-throughput techniques to characterize photosynthesis at spatial scales useful to infer treatment or genotypic variation in field-based experiments or breeding trials. We will accomplish this objective by presenting six lessons learned thus far through the development and application of proximal/remote sensing-based measurements and the accompanying statistical analyses. We will conclude by outlining what we perceive as the current limitations, bottlenecks, and opportunities facing HTP of photosynthesis.
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Affiliation(s)
- Peng Fu
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Champaign, IL, USA
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Christopher M Montes
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- United States Department of Agriculture, Global Change and Photosynthesis Research Unit, Agricultural Research Service, Urbana, IL, USA
| | - Matthew H Siebers
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- United States Department of Agriculture, Global Change and Photosynthesis Research Unit, Agricultural Research Service, Urbana, IL, USA
| | - Nuria Gomez-Casanovas
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Institute for Sustainability, Energy & Environment, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Justin M McGrath
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- United States Department of Agriculture, Global Change and Photosynthesis Research Unit, Agricultural Research Service, Urbana, IL, USA
| | - Elizabeth A Ainsworth
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Champaign, IL, USA
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- United States Department of Agriculture, Global Change and Photosynthesis Research Unit, Agricultural Research Service, Urbana, IL, USA
- Institute for Sustainability, Energy & Environment, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Carl J Bernacchi
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Champaign, IL, USA
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- United States Department of Agriculture, Global Change and Photosynthesis Research Unit, Agricultural Research Service, Urbana, IL, USA
- Institute for Sustainability, Energy & Environment, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Correspondence:
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Sales CRG, da Silva AB, Carmo-Silva E. Measuring Rubisco activity: challenges and opportunities of NADH-linked microtiter plate-based and 14C-based assays. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:5302-5312. [PMID: 32728715 PMCID: PMC7501812 DOI: 10.1093/jxb/eraa289] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 06/22/2020] [Indexed: 05/28/2023]
Abstract
Rubisco is central to carbon assimilation, and efforts to improve the efficiency and sustainability of crop production have spurred interest in phenotyping Rubisco activity. We tested the hypothesis that microtiter plate-based methods provide comparable results to those obtained with the radiometric assay that measures the incorporation of 14CO2 into 3-phosphoglycerate (3-PGA). Three NADH-linked assays were tested that use alternative coupling enzymes: glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and glycerolphosphate dehydrogenase (GlyPDH); phosphoenolpyruvate carboxylase (PEPC) and malate dehydrogenase (MDH); and pyruvate kinase (PK) and lactate dehydrogenase (LDH). To date there has been no thorough evaluation of their reliability by comparison with the 14C-based method. The three NADH-linked assays were used in parallel to estimate (i) the 3-PGA concentration-response curve of NADH oxidation, (ii) the Michaelis-Menten constant for ribulose-1,5-bisphosphate, (iii) fully active and inhibited Rubisco activities, and (iv) Rubisco initial and total activities in fully illuminated and shaded leaves. All three methods correlated strongly with the 14C-based method, and the PK-LDH method showed a strong correlation and was the cheapest method. PEPC-MDH would be a suitable option for situations in which ADP/ATP might interfere with the assay. GAPDH-GlyPDH proved more laborious than the other methods. Thus, we recommend the PK-LDH method as a reliable, cheaper, and higher throughput method to phenotype Rubisco activity for crop improvement efforts.
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Affiliation(s)
- Cristina R G Sales
- Lancaster Environment Centre, Lancaster University, Library Avenue, Lancaster, UK
| | - Anabela Bernardes da Silva
- BioISI - Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
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Chen G, Zheng Z, Bai M, Li Q. Chronic effects of microcystin-LR at environmental relevant concentrations on photosynthesis of Typha angustifolia Linn. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:514-523. [PMID: 32277321 DOI: 10.1007/s10646-020-02196-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/13/2020] [Indexed: 05/11/2023]
Abstract
Understanding the growth and development of aquatic plants in eutrophic water is of great significance for the selection of potential candidate plant for use in the phytoremediation of eutrophic aquatic ecosystems. The present study aimed to investigate the chronic effects of microcystin-LR (MC-LR) on photosynthesis in the leaves of Typha angustifolia Linn. Photosynthetic activity was stimulated in the leaves following exposure to 4.6 μg L-1 MC-LR for six weeks based on the enhancement of Ribulose-1, 5-bisphosphate carboxylase/oxygenase (Rubisco) activity and net photosynthetic rate (PN). However, PN decreased significantly after exposure to 49.1 or 98.3 μg L-1 MC-LR, via non-stomatal limitation by reducing the chlorophyll a and b contents and Rubisco activity. In addition, glycolate oxidase (GO) and serine:glyoxylate aminotransferase (SGAT) activities decreased significantly, indicating that the photorespiration pathway was affected adversely. The intercellular carbon dioxide (Ci) concentration decreased significantly following exposure to 98.3 μg L-1 MC-LR, accompanied with decreases in PN and stomatal conductivity (gs), indicating that stomatal limitation on the photosynthesis system in T. angustifolia L. was observed after exposure to 98.3 μg L-1 MC-LR. Under long-term exposure to MC-LR (49.1-98.3 μg L-1), oxidation stress was severe in the aquatic plant, and non-stomatal limitation or stomatal limitation effects on the photosynthesis system were obvious, resulting in decreases in photosynthesis rates.
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Affiliation(s)
- Guoyuan Chen
- College of Environment Science and Engineering, Xiamen University of Technology, Ligong Road 600, 361024, Xiamen, China.
| | - Zhihong Zheng
- College of Environment Science and Engineering, Xiamen University of Technology, Ligong Road 600, 361024, Xiamen, China
| | - Mingxian Bai
- College of Environment Science and Engineering, Xiamen University of Technology, Ligong Road 600, 361024, Xiamen, China
| | - Qingsong Li
- College of Environment Science and Engineering, Xiamen University of Technology, Ligong Road 600, 361024, Xiamen, China
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Busch FA, Tominaga J, Muroya M, Shirakami N, Takahashi S, Yamori W, Kitaoka T, Milward SE, Nishimura K, Matsunami E, Toda Y, Higuchi C, Muranaka A, Takami T, Watanabe S, Kinoshita T, Sakamoto W, Sakamoto A, Shimada H. Overexpression of BUNDLE SHEATH DEFECTIVE 2 improves the efficiency of photosynthesis and growth in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 102:129-137. [PMID: 31755157 PMCID: PMC7217058 DOI: 10.1111/tpj.14617] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 11/01/2019] [Accepted: 11/12/2019] [Indexed: 05/16/2023]
Abstract
Bundle Sheath Defective 2, BSD2, is a stroma-targeted protein initially identified as a factor required for the biogenesis of ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO) in maize. Plants and algae universally have a homologous gene for BSD2 and its deficiency causes a RuBisCO-less phenotype. As RuBisCO can be the rate-limiting step in CO2 assimilation, the overexpression of BSD2 might improve photosynthesis and productivity through the accumulation of RuBisCO. To examine this hypothesis, we produced BSD2 overexpression lines in Arabidopsis. Compared with wild type, the BSD2 overexpression lines BSD2ox-2 and BSD2ox-3 expressed 4.8-fold and 8.8-fold higher BSD2 mRNA, respectively, whereas the empty-vector (EV) harbouring plants had a comparable expression level. The overexpression lines showed a significantly higher CO2 assimilation rate per available CO2 and productivity than EV plants. The maximum carboxylation rate per total catalytic site was accelerated in the overexpression lines, while the number of total catalytic sites and RuBisCO content were unaffected. We then isolated recombinant BSD2 (rBSD2) from E. coli and found that rBSD2 reduces disulfide bonds using reductants present in vivo, for example glutathione, and that rBSD2 has the ability to reactivate RuBisCO that has been inactivated by oxidants. Furthermore, 15% of RuBisCO freshly isolated from leaves of EV was oxidatively inactivated, as compared with 0% in BSD2-overexpression lines, suggesting that the overexpression of BSD2 maintains RuBisCO to be in the reduced active form in vivo. Our results demonstrated that the overexpression of BSD2 improves photosynthetic efficiency in Arabidopsis and we conclude that it is involved in mediating RuBisCO activation.
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Affiliation(s)
- Florian A. Busch
- Research School of BiologyAustralian National UniversityCanberraAustralian Capital Territory2601Australia
| | - Jun Tominaga
- Graduate School of Integrated Sciences for LifeHiroshima University1‐3‐1 KagamiyamaHigashi‐Hiroshima739‐8526Japan
| | - Masato Muroya
- Graduate School of Integrated Sciences for LifeHiroshima University1‐3‐1 KagamiyamaHigashi‐Hiroshima739‐8526Japan
| | - Norihiko Shirakami
- Graduate School of Integrated Sciences for LifeHiroshima University1‐3‐1 KagamiyamaHigashi‐Hiroshima739‐8526Japan
| | - Shunichi Takahashi
- Research School of BiologyAustralian National UniversityCanberraAustralian Capital Territory2601Australia
- Present address:
Division of Environmental PhotobiologyNational Institute for Basic BiologyOkazaki444‐8585Japan
| | - Wataru Yamori
- Graduate School of ScienceUniversity of TokyoBunkyo‐kuTokyo113‐0033Japan
| | - Takuya Kitaoka
- Division of Biological ScienceGraduate School of ScienceNagoya UniversityChikusaNagoya464‐8602Japan
| | - Sara E. Milward
- Research School of BiologyAustralian National UniversityCanberraAustralian Capital Territory2601Australia
| | - Kohji Nishimura
- Department of Molecular and Functional GenomicsInterdisciplinary Center for Science ResearchOrganization of ResearchShimane UniversityNishikawatsu 1060Matsue690‐8504Japan
| | - Erika Matsunami
- Department of Molecular and Functional GenomicsInterdisciplinary Center for Science ResearchOrganization of ResearchShimane UniversityNishikawatsu 1060Matsue690‐8504Japan
| | - Yosuke Toda
- Graduate School of ScienceUniversity of TokyoBunkyo‐kuTokyo113‐0033Japan
| | - Chikako Higuchi
- Graduate School of Integrated Sciences for LifeHiroshima University1‐3‐1 KagamiyamaHigashi‐Hiroshima739‐8526Japan
| | - Atsuko Muranaka
- Graduate School of Integrated Sciences for LifeHiroshima University1‐3‐1 KagamiyamaHigashi‐Hiroshima739‐8526Japan
| | - Tsuneaki Takami
- Institute of Plant Science and ResourcesOkayama UniversityKurashikiOkayama710‐0046Japan
| | - Shunsuke Watanabe
- Graduate School of Integrated Sciences for LifeHiroshima University1‐3‐1 KagamiyamaHigashi‐Hiroshima739‐8526Japan
- Present address:
RIKEN Center for Sustainable Resource ScienceSuehiro‐cho, 1‐7‐22, Tsurumi‐kuYokohamaKanagawa230‐0045Japan
| | - Toshinori Kinoshita
- Division of Biological ScienceGraduate School of ScienceNagoya UniversityChikusaNagoya464‐8602Japan
- Institute of Transformative Bio‐Molecules (WPI‐ITbM)Nagoya UniversityChikusaNagoya464‐8602Japan
| | - Wataru Sakamoto
- Institute of Plant Science and ResourcesOkayama UniversityKurashikiOkayama710‐0046Japan
| | - Atsushi Sakamoto
- Graduate School of Integrated Sciences for LifeHiroshima University1‐3‐1 KagamiyamaHigashi‐Hiroshima739‐8526Japan
| | - Hiroshi Shimada
- Graduate School of Integrated Sciences for LifeHiroshima University1‐3‐1 KagamiyamaHigashi‐Hiroshima739‐8526Japan
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Sundyreva M, Rebrov A, Mishko A. Influence of sucrose concentration in the culture medium on the condition of the photosynthetic apparatus of grapes cultured in vitro. BIO WEB OF CONFERENCES 2020. [DOI: 10.1051/bioconf/20202504003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
An influence of different sucrose concentrations in the culture media on the photosynthetic parameters, photosynthetic apparatus related genes expression, oxidative processes and acclimation of grape plants cultured in vitro was examined in this article. An increase of the sucrose concentration in the culture media resulted in a reduced expression of several photosynthetic genes. The most effective functioning of the photosynthetic apparatus was discovered by a decreased amount of surcose in culture media. An increase of the sucrose concentration in the culture media disrupts pigments synthesis, particularly carotenoids, which can be a cause of the secondary oxidative stress formation and grape plants growth reduction during acclimation.
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Scafaro AP, De Vleesschauwer D, Bautsoens N, Hannah MA, den Boer B, Gallé A, Van Rie J. A single point mutation in the C-terminal extension of wheat Rubisco activase dramatically reduces ADP inhibition via enhanced ATP binding affinity. J Biol Chem 2019; 294:17931-17940. [PMID: 31530638 PMCID: PMC6879333 DOI: 10.1074/jbc.ra119.010684] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 09/15/2019] [Indexed: 01/23/2023] Open
Abstract
Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) activase (Rca) is a AAA+ enzyme that uses ATP to remove inhibitors from the active site of Rubisco, the central carboxylation enzyme of photosynthesis. Rca α and β isoforms exist in most higher plant species, with the α isoform being identical to the β form but having an additional 25-45 amino acids at the Rca C terminus, known as the C-terminal extension (CTE). Rca is inhibited by ADP, and the extent of ADP sensitivity of the Rca complex can be modulated by the CTE of the α isoform, particularly in relation to a disulfide bond structure that is specifically reduced by the redox-regulatory enzyme thioredoxin-f. Here, we introduced single point mutations of Lys-428 in the CTE of Rca-α from wheat (Triticum aestivum) (TaRca2-α). Substitution of Lys-428 with Arg dramatically altered ADP inhibition, independently of thioredoxin-f regulation. We determined that the reduction in ADP inhibition in the K428R variant is not due to a change in ADP affinity, as the apparent constant for ADP binding was not altered by the K428R substitution. Rather, we observed that the K428R substitution strongly increased ATP substrate affinity and ATP-dependent catalytic velocity. These results suggest that the Lys-428 residue is involved in interacting with the γ-phosphate of ATP. Considering that nucleotide-dependent Rca activity regulates Rubisco and thus photosynthesis during fluctuating irradiance, the K428R substitution could potentially provide a mechanism for boosting the performance of wheat grown in the dynamic light environments of the field.
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Affiliation(s)
- Andrew P Scafaro
- BASF Belgium Coordination Center-Innovation Center Gent, Technologiepark 101, Gent 9052, Belgium
| | - David De Vleesschauwer
- BASF Belgium Coordination Center-Innovation Center Gent, Technologiepark 101, Gent 9052, Belgium
| | - Nadine Bautsoens
- BASF Belgium Coordination Center-Innovation Center Gent, Technologiepark 101, Gent 9052, Belgium
| | - Matthew A Hannah
- BASF Belgium Coordination Center-Innovation Center Gent, Technologiepark 101, Gent 9052, Belgium
| | - Bart den Boer
- BASF Belgium Coordination Center-Innovation Center Gent, Technologiepark 101, Gent 9052, Belgium
| | - Alexander Gallé
- BASF Belgium Coordination Center-Innovation Center Gent, Technologiepark 101, Gent 9052, Belgium
| | - Jeroen Van Rie
- BASF Belgium Coordination Center-Innovation Center Gent, Technologiepark 101, Gent 9052, Belgium
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Scafaro AP, Bautsoens N, den Boer B, Van Rie J, Gallé A. A Conserved Sequence from Heat-Adapted Species Improves Rubisco Activase Thermostability in Wheat. PLANT PHYSIOLOGY 2019; 181:43-54. [PMID: 31189658 PMCID: PMC6716234 DOI: 10.1104/pp.19.00425] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 05/31/2019] [Indexed: 05/06/2023]
Abstract
The central enzyme of photosynthesis, Rubisco, is regulated by Rubisco activase (Rca). Photosynthesis is impaired during heat stress, and this limitation is often attributed to the heat-labile nature of Rca. We characterized gene expression and protein thermostability for the three Rca isoforms present in wheat (Triticum aestivum), namely TaRca1-β, TaRca2-α, and TaRca2-β. Furthermore, we compared wheat Rca with one of the two Rca isoforms from rice (Oryza sativa; OsRca-β) and Rca from other species adapted to warm environments. The TaRca1 gene was induced, whereas TaRca2 was suppressed by heat stress. The TaRca2 isoforms were sensitive to heat degradation, with thermal midpoints of 35°C ± 0.3°C, the temperature at which Rubisco activation velocity by Rca was halved. By contrast, TaRca1-β was more thermotolerant, with a thermal midpoint of 42°C, matching that of rice OsRca-β. Mutations of the TaRca2-β isoform based on sequence alignment of the thermostable TaRca1-β from wheat, OsRca-β from rice, and a consensus sequence representing Rca from warm-adapted species enabled the identification of 11 amino acid substitutions that improved its thermostability by greater than 7°C without a reduction in catalytic velocity at a standard 25°C. Protein structure modeling and mutational analysis suggested that the thermostability of these mutational variants arises from monomeric and not oligomeric thermal stabilization. These results provide a mechanism for improving the heat stress tolerance of photosynthesis in wheat and potentially other species, which is a desirable outcome considering the likelihood that crops will face more frequent heat stress conditions over the coming decades.
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Affiliation(s)
- Andrew P Scafaro
- BASF Agricultural Solutions, Ghent 9052, Belgium
- Australian Research Council Centre of Excellence in Plant Energy Biology, Research School of Biology, Australian National University, Canberra, Australian Capital Territory 2601, Australia
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An F, Chen T, Li QX, Qiao J, Zhang Z, Carvalho LJ, Li K, Chen S. Protein Cross-Interactions for Efficient Photosynthesis in the Cassava Cultivar SC205 Relative to Its Wild Species. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:8746-8755. [PMID: 31322881 DOI: 10.1021/acs.jafc.9b00046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The underlying mechanisms of the higher photosynthetic efficiency of cultivated cassava relative to its wild species are poorly understood. In the present study, proteins in leaves and chloroplasts were analyzed to compare the differences among the cultivar SC205, its wild ancestor W14, and the related species Glaziovii. The functions of differential proteins are associated with 10 ontology groups including photosynthesis, carbohydrate and energy metabolism, as well as potential signal pathway. The protein-protein networks among 41 differential proteins showed that PGK1 is a hub protein and protein cross-interactions affected the differentiation of photosynthetic rate. Anatomy patterns and PEPC detection suggested that SC205 has more C4 photosynthesis characteristics than Glaziovii and W14. Finally, a mechanism model of the efficient photosynthesis was proposed based on the remarkable variations in photosynthetic parameters and protein functions in the domestic cultivars.
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Affiliation(s)
- Feifei An
- Tropical Crops Genetic Resources Institute , Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Ministry of Agriculture for Germplasm Resources Conservation and Utilization of Cassava , Danzhou 571737 , China
| | - Ting Chen
- College of Agronomy , Hainan University , Haikou 571101 , China
| | - Qing X Li
- Department of Molecular Biosciences and Bioengineering , University of Hawaii at Manoa , Honolulu , Hawaii 96822 , United States
| | - Jingjuan Qiao
- College of Agronomy , Hainan University , Haikou 571101 , China
| | - Zhenwen Zhang
- Tropical Crops Genetic Resources Institute , Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Ministry of Agriculture for Germplasm Resources Conservation and Utilization of Cassava , Danzhou 571737 , China
| | - Luiz Jcb Carvalho
- Genetic Resources and Biotechnology , Embrapa , Brasilia , 70770-917 Brazil
| | - Kaimian Li
- Tropical Crops Genetic Resources Institute , Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Ministry of Agriculture for Germplasm Resources Conservation and Utilization of Cassava , Danzhou 571737 , China
| | - Songbi Chen
- Tropical Crops Genetic Resources Institute , Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Ministry of Agriculture for Germplasm Resources Conservation and Utilization of Cassava , Danzhou 571737 , China
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Hájková M, Kummerová M, Zezulka Š, Babula P, Váczi P. Diclofenac as an environmental threat: Impact on the photosynthetic processes of Lemna minor chloroplasts. CHEMOSPHERE 2019; 224:892-899. [PMID: 30986895 DOI: 10.1016/j.chemosphere.2019.02.197] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 02/27/2019] [Accepted: 02/28/2019] [Indexed: 05/03/2023]
Abstract
Mechanisms of pharmaceuticals action on biochemical and physiological processes in plants that determine plant growth and development are still mostly unknown. This study deals with the effects of non-steroidal anti-inflammatory drug diclofenac (DCF) on photosynthesis as an essential anabolic process. Changes in primary and secondary photosynthetic processes were assessed in chloroplasts isolated from Lemna minor exposed to 1, 10, 100, and 1000 μM DCF. Decreases in the potential and effective quantum yields of photosystem II (FV/FM by 21%, ΦII by 44% compared to control), changes in non-photochemical fluorescence quenching (NPQ), and a substantial drop in Hill reaction activity (by 73%), especially under 1000 μM DCF, were found. Limitation of electron transport through photosystem II was confirmed by increased fluorescence signals in steps J and I (by 50% and 23%, respectively, under 1000 μM DCF) in OJIP fluorescence transient. Photosystem I exhibited changes only in the redox state of P700 reaction centres (decrease in Pm by 10%, increase in reduced P700 by 5% under 1000 μM DCF). Similarly, RuBisCO activity was only lowered by 30% under 1000 μM DCF. In contrast, a significant increase in reactive oxygen and nitrogen species (by 116% and 157%, respectively) was observed under 10 μM DCF, and lipid peroxidation increased even at 1 μM DCF (by nearly seven times compared to the control). Results demonstrate the ability of environmentally relevant DCF concentrations to induce oxidative stress in isolated duckweed chloroplasts; however, photosynthetic processes were affected considerably only by the highest DCF treatments.
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Affiliation(s)
- Markéta Hájková
- Department of Plant Physiology and Anatomy, Institute of Experimental Biology, Faculty of Science, Masaryk University Brno, Kotlářská 2, 611 37 Brno, Czech Republic.
| | - Marie Kummerová
- Department of Plant Physiology and Anatomy, Institute of Experimental Biology, Faculty of Science, Masaryk University Brno, Kotlářská 2, 611 37 Brno, Czech Republic.
| | - Štěpán Zezulka
- Department of Plant Physiology and Anatomy, Institute of Experimental Biology, Faculty of Science, Masaryk University Brno, Kotlářská 2, 611 37 Brno, Czech Republic.
| | - Petr Babula
- Department of Physiology, Faculty of Medicine, Masaryk University Brno, Kamenice 753/5, 625 00 Brno, Czech Republic.
| | - Peter Váczi
- Department of Plant Physiology and Anatomy, Institute of Experimental Biology, Faculty of Science, Masaryk University Brno, Kotlářská 2, 611 37 Brno, Czech Republic.
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10
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Jensen AM, Warren JM, King AW, Ricciuto DM, Hanson PJ, Wullschleger SD. Simulated projections of boreal forest peatland ecosystem productivity are sensitive to observed seasonality in leaf physiology†. TREE PHYSIOLOGY 2019; 39:556-572. [PMID: 30668859 DOI: 10.1093/treephys/tpy140] [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: 08/03/2018] [Revised: 01/11/2018] [Accepted: 12/07/2018] [Indexed: 06/09/2023]
Abstract
We quantified seasonal CO2 assimilation capacities for seven dominant vascular species in a wet boreal forest peatland then applied data to a land surface model parametrized to the site (ELM-SPRUCE) to test if seasonality in photosynthetic parameters results in differences in simulated plant responses to elevated CO2 and temperature. We collected seasonal leaf-level gas exchange, nutrient content and stand allometric data from the field-layer community (i.e., Maianthemum trifolium (L.) Sloboda), understory shrubs (Rhododendron groenlandicum (Oeder) Kron and Judd, Chamaedaphne calyculata (L.) Moench., Kalmia polifolia Wangenh. and Vaccinium angustifolium Alton.) and overstory trees (Picea mariana (Mill.) B.S.P. and Larix laricina (Du Roi) K. Koch). We found significant interspecific seasonal differences in specific leaf area, nitrogen content (by area; Na) and photosynthetic parameters (i.e., maximum rates of Rubisco carboxylation (Vcmax25°C), electron transport (Jmax25°C) and dark respiration (Rd25°C)), but minimal correlation between foliar Na and Vcmax25°C, Jmax25°C or Rd25°C, which illustrates that nitrogen alone is not a good correlate for physiological processes such as Rubisco activity that can change seasonally in this system. ELM-SPRUCE was sensitive to the introduction of observed interspecific seasonality in Vcmax25°C, Jmax25°C and Rd25°C, leading to simulated enhancement of net primary production (NPP) using seasonally dynamic parameters as compared with use of static parameters. This pattern was particularly pronounced under simulations with higher temperature and elevated CO2, suggesting a key hypothesis to address with future empirical or observational studies as climate changes. Inclusion of species-specific seasonal photosynthetic parameters should improve estimates of boreal ecosystem-level NPP, especially if impacts of seasonal physiological ontogeny can be separated from seasonal thermal acclimation.
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Affiliation(s)
- Anna M Jensen
- Climate Change Science Institute & Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Jeffrey M Warren
- Climate Change Science Institute & Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Anthony W King
- Climate Change Science Institute & Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Daniel M Ricciuto
- Climate Change Science Institute & Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Paul J Hanson
- Climate Change Science Institute & Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Stan D Wullschleger
- Climate Change Science Institute & Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
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11
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Sales CRG, Degen GE, da Silva AB, Carmo-Silva E. Spectrophotometric Determination of RuBisCO Activity and Activation State in Leaf Extracts. Methods Mol Biol 2019; 1770:239-250. [PMID: 29978406 DOI: 10.1007/978-1-4939-7786-4_14] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
RuBisCO plays a central role in photosynthesis and, due to its catalytic inefficiencies, frequently limits CO2 assimilation in fully illuminated leaves at the top of unstressed crop canopies. The CO2-fixing enzyme is heavily regulated and not all the enzyme present in the leaf is active at any given moment. In this chapter, a spectrophotometric assay is described for measuring RuBisCO activity and activation state in leaf extracts. Most of the assay components are available commercially and others can be produced by established protocols, making adoption of the assay achievable by most plant biochemistry laboratories. Its relative high-throughput capacity enables large-scale experiments aimed at screening germplasm for improved RuBisCO function.
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Affiliation(s)
| | - Gustaf E Degen
- Lancaster Environment Centre, Lancaster University, Lancaster, UK
| | - Anabela Bernardes da Silva
- Faculdade de Ciências, Departamento de Biologia Vegetal e Centro de Biodiversidade, Genómica Integrativa e Funcional (BioFIG), Universidade de Lisboa, Lisbon, Portugal
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12
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Serban AJ, Breen IL, Bui HQ, Levitus M, Wachter RM. Assembly-disassembly is coupled to the ATPase cycle of tobacco Rubisco activase. J Biol Chem 2018; 293:19451-19465. [PMID: 30352875 PMCID: PMC6302163 DOI: 10.1074/jbc.ra118.005047] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 10/09/2018] [Indexed: 11/06/2022] Open
Abstract
The carbon-fixing activity of enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) is regulated by Rubisco activase (Rca), a ring-forming ATPase that catalyzes inhibitor release. For higher plant Rca, the catalytic roles played by different oligomeric species have remained obscure. Here, we utilized fluorescence-correlation spectroscopy to estimate dissociation constants for the dimer-tetramer, tetramer-hexamer, hexamer-12-mer, and higher-order assembly equilibria of tobacco Rca. A comparison of oligomer composition with ATPase activity provided evidence that assemblies larger than hexamers are hydrolytically inactive. Therefore, supramolecular aggregates may serve as storage forms at low-energy charge. We observed that the tetramer accumulates only when both substrate and product nucleotides are bound. During rapid ATP turnover, about one in six active sites was occupied by ADP, and ∼36% of Rca was tetrameric. The steady-state catalytic rate reached a maximum between 0.5 and 2.5 μm Rca. In this range, significant amounts of dimers, tetramers, and hexamers coexisted, although none could fully account for the observed activity profile. Therefore, we propose that dynamic assembly-disassembly partakes in the ATPase cycle. According to this model, the association of dimers with tetramers generates a hexamer that forms a closed ring at high ATP and magnesium levels. Upon hydrolysis and product release, the toroid breaks open and dissociates into a dimer and tetramer, which may be coupled to Rubisco remodeling. Although a variant bearing the R294V substitution assembled in much the same way, highly stabilized states could be generated by binding of a transition-state analog. A tight-binding pre-hydrolysis state appears to become more accessible in thermally labile Rcas.
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Affiliation(s)
- Andrew J Serban
- From the School of Molecular Sciences
- Center for Bioenergy and Photosynthesis
- Biodesign Center for Applied Structural Discovery, and
| | - Isabella L Breen
- From the School of Molecular Sciences
- Center for Bioenergy and Photosynthesis
- Biodesign Center for Applied Structural Discovery, and
| | - Hoang Q Bui
- From the School of Molecular Sciences
- Center for Bioenergy and Photosynthesis
- Biodesign Center for Applied Structural Discovery, and
| | - Marcia Levitus
- From the School of Molecular Sciences,
- the Biodesign Center for Single Molecule Biophysics, Arizona State University, Tempe, Arizona 85287
| | - Rebekka M Wachter
- From the School of Molecular Sciences,
- Center for Bioenergy and Photosynthesis
- Biodesign Center for Applied Structural Discovery, and
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13
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Jauregui I, Rothwell SA, Taylor SH, Parry MAJ, Carmo-Silva E, Dodd IC. Whole plant chamber to examine sensitivity of cereal gas exchange to changes in evaporative demand. PLANT METHODS 2018; 14:97. [PMID: 30410567 PMCID: PMC6211548 DOI: 10.1186/s13007-018-0357-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 10/08/2018] [Indexed: 05/29/2023]
Abstract
BACKGROUND Improving plant water use efficiency (WUE) is a major target for improving crop yield resilience to adverse climate change. Identifying genetic variation in WUE usually relies on instantaneous measurements of photosynthesis (An) and transpiration (Tr), or integrative measurements of carbon isotope discrimination, at the leaf level. However, leaf gas exchange measurements alone do not adequately represent whole plant responses, especially if evaporative demand around the plant changes. RESULTS Here we describe a whole plant gas exchange system that can rapidly alter evaporative demand when measuring An, Tr and intrinsic WUE (iWUE) and identify genetic variation in this response. An was not limited by VPD under steady-state conditions but some wheat cultivars restricted Tr under high evaporative demand, thereby improving iWUE. These changes may be ABA-dependent, since the barley ABA-deficient mutant (Az34) failed to restrict Tr under high evaporative demand. Despite higher Tr, Az34 showed lower An than wild-type (WT) barley because of limitations in Rubisco carboxylation activity. Tr and An of Az34 were more sensitive than WT barley to exogenous spraying with ABA, which restricted photosynthesis via substrate limitation and decreasing Rubisco activation. CONCLUSIONS Examining whole plant gas exchange responses to altered VPD can identify genetic variation in whole plant iWUE, and facilitate an understanding of the underlying mechanism(s).
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Affiliation(s)
- Iván Jauregui
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ UK
- Present Address: Plant Genetics, TERRA Teaching and Research Center, Gembloux Agro Bio-Tech, University of Liège, Gembloux, 5030 Belgium
| | - Shane A. Rothwell
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ UK
| | - Samuel H. Taylor
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ UK
| | - Martin A. J. Parry
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ UK
| | | | - Ian C. Dodd
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ UK
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14
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Abstract
Increases in ambient temperatures have been a severe threat to crop production in many countries around the world under climate change. Chloroplasts serve as metabolic centers and play a key role in physiological adaptive processes to heat stress. In addition to expressing heat shock proteins that protect proteins from heat-induced damage, metabolic reprogramming occurs during adaptive physiological processes in chloroplasts. Heat stress leads to inhibition of plant photosynthetic activity by damaging key components functioning in a variety of metabolic processes, with concomitant reductions in biomass production and crop yield. In this review article, we will focus on events through extensive and transient metabolic reprogramming in response to heat stress, which included chlorophyll breakdown, generation of reactive oxygen species (ROS), antioxidant defense, protein turnover, and metabolic alterations with carbon assimilation. Such diverse metabolic reprogramming in chloroplasts is required for systemic acquired acclimation to heat stress in plants.
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Affiliation(s)
- Qing-Long Wang
- The National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China.
| | - Juan-Hua Chen
- The National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China.
| | - Ning-Yu He
- The National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China.
| | - Fang-Qing Guo
- The National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China.
- CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China.
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15
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Ogbaga CC, Stepien P, Athar HUR, Ashraf M. Engineering Rubisco activase from thermophilic cyanobacteria into high-temperature sensitive plants. Crit Rev Biotechnol 2017; 38:559-572. [DOI: 10.1080/07388551.2017.1378998] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Chukwuma C. Ogbaga
- Department of Biological Sciences, Nile University of Nigeria, Abuja, Nigeria
| | - Piotr Stepien
- Department of Plant Nutrition, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland
| | - Habib-Ur-Rehman Athar
- Institute of Pure and Applied Biology, Bahauddin Zakariya University, Multan, Pakistan
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16
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Peterson-Forbrook DS, Hilton MT, Tichacek L, Henderson JN, Bui HQ, Wachter RM. Nucleotide Dependence of Subunit Rearrangements in Short-Form Rubisco Activase from Spinach. Biochemistry 2017; 56:4906-4921. [PMID: 28795566 DOI: 10.1021/acs.biochem.7b00574] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Higher-plant Rubisco activase (Rca) plays a critical role in regulating the activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). In vitro, Rca is known to undergo dynamic assembly-disassembly processes, with several oligomer stoichiometries coexisting over a broad concentration range. Although the hexamer appears to be the active form, changes in quaternary structure could play a role in Rubisco regulation. Therefore, fluorescent labels were attached to the C-termini of spinach β-Rca, and the rate of subunit mixing was monitored by measuring energy transfer as a function of nucleotide and divalent cation. Only dimeric units appeared to exchange. Poorly hydrolyzable substrate analogues provided locked complexes with high thermal stabilities (apparent Tm = 60 °C) and an estimated t1/2 of at least 7 h, whereas ATP-Mg provided tight assemblies with t1/2 values of 30-40 min and ADP-Mg loose assemblies with t1/2 values of <15 min. Accumulation of ADP to 20% of the total level of adenine nucleotide substantially accelerated equilibration. An initial lag period was observed with ATP·Mg, indicating inhibition of subunit exchange at low ADP concentrations. The ADP Ki value was estimated to exceed the Km for ATP (0.772 ± 96 mM), suggesting that the equilibration rate is a function of the relative contributions of high- and low-affinity states. C-Terminal cross-linking generated covalent dimers, required the N-terminal extension to the AAA+ domain, and provided evidence of different classes of sites. We propose that oligomer reorganization may be stalled during periods of high Rubisco reactivation activity, whereas changes in quaternary structure are stimulated by the accumulation of ADP at low light levels.
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Affiliation(s)
- Dayna S Peterson-Forbrook
- School of Molecular Sciences, School of Life Sciences, and Center for Bioenergy and Photosynthesis, Arizona State University , Tempe, Arizona 85287, United States
| | - Matthew T Hilton
- School of Molecular Sciences, School of Life Sciences, and Center for Bioenergy and Photosynthesis, Arizona State University , Tempe, Arizona 85287, United States
| | - Laura Tichacek
- School of Molecular Sciences, School of Life Sciences, and Center for Bioenergy and Photosynthesis, Arizona State University , Tempe, Arizona 85287, United States
| | - J Nathan Henderson
- School of Molecular Sciences, School of Life Sciences, and Center for Bioenergy and Photosynthesis, Arizona State University , Tempe, Arizona 85287, United States
| | - Hoang Q Bui
- School of Molecular Sciences, School of Life Sciences, and Center for Bioenergy and Photosynthesis, Arizona State University , Tempe, Arizona 85287, United States
| | - Rebekka M Wachter
- School of Molecular Sciences, School of Life Sciences, and Center for Bioenergy and Photosynthesis, Arizona State University , Tempe, Arizona 85287, United States
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17
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Mueller-Cajar O. The Diverse AAA+ Machines that Repair Inhibited Rubisco Active Sites. Front Mol Biosci 2017; 4:31. [PMID: 28580359 PMCID: PMC5437159 DOI: 10.3389/fmolb.2017.00031] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 04/29/2017] [Indexed: 11/13/2022] Open
Abstract
Gaseous carbon dioxide enters the biosphere almost exclusively via the active site of the enzyme ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco). This highly conserved catalyst has an almost universal propensity to non-productively interact with its substrate ribulose 1,5-bisphosphate, leading to the formation of dead-end inhibited complexes. In diverse autotrophic organisms this tendency has been counteracted by the recruitment of dedicated AAA+ (ATPases associated with various cellular activities) proteins that all use the energy of ATP hydrolysis to remodel inhibited Rubisco active sites leading to release of the inhibitor. Three evolutionarily distinct classes of these Rubisco activases (Rcas) have been discovered so far. Green and red-type Rca are mostly found in photosynthetic eukaryotes of the green and red plastid lineage respectively, whereas CbbQO is associated with chemoautotrophic bacteria. Ongoing mechanistic studies are elucidating how the various motors are utilizing both similar and contrasting strategies to ultimately perform their common function of cracking the inhibited Rubisco active site. The best studied mechanism utilized by red-type Rca appears to involve transient threading of the Rubisco large subunit C-terminal peptide, reminiscent of the action performed by Clp proteases. As well as providing a fascinating example of convergent molecular evolution, Rca proteins can be considered promising crop-improvement targets. Approaches aiming to replace Rubisco in plants with improved enzymes will need to ensure the presence of a compatible Rca protein. The thermolability of the Rca protein found in crop plants provides an opportunity to fortify photosynthesis against high temperature stress. Photosynthesis also appears to be limited by Rca when light conditions are fluctuating. Synthetic biology strategies aiming to enhance the autotrophic CO2 fixation machinery will need to take into consideration the requirement for Rubisco activases as well as their properties.
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Affiliation(s)
- Oliver Mueller-Cajar
- School of Biological Sciences, Nanyang Technological UniversitySingapore, Singapore
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18
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Perdomo JA, Capó-Bauçà S, Carmo-Silva E, Galmés J. Rubisco and Rubisco Activase Play an Important Role in the Biochemical Limitations of Photosynthesis in Rice, Wheat, and Maize under High Temperature and Water Deficit. FRONTIERS IN PLANT SCIENCE 2017; 8:490. [PMID: 28450871 PMCID: PMC5390490 DOI: 10.3389/fpls.2017.00490] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 03/21/2017] [Indexed: 05/19/2023]
Abstract
To understand the effect of heat and drought on three major cereal crops, the physiological and biochemical (i.e., metabolic) factors affecting photosynthesis were examined in rice, wheat, and maize plants grown under long-term water deficit (WD), high temperature (HT) and the combination of both stresses (HT-WD). Diffusional limitations to photosynthesis prevailed under WD for the C3 species, rice and wheat. Conversely, biochemical limitations prevailed under WD for the C4 species, maize, under HT for all three species, and under HT-WD in rice and maize. These biochemical limitations to photosynthesis were associated with Rubisco activity that was highly impaired at HT and under HT-WD in the three species. Decreases in Rubisco activation were unrelated to the amount of Rubisco and Rubisco activase (Rca), but were probably caused by inhibition of Rca activity, as suggested by the mutual decrease and positive correlation between Rubisco activation state and the rate of electron transport. Decreased Rubisco activation at HT was associated with biochemical limitation of net CO2 assimilation rate (AN). Overall, the results highlight the importance of Rubisco as a target for improving the photosynthetic performance of these C3 (wheat and rice) and C4 (maize) cereal crops under increasingly variable and warmer climates.
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Affiliation(s)
- Juan A. Perdomo
- Plant Biology and Crop Science, Rothamsted Research (BBSRC)Harpenden, UK
| | - Sebastià Capó-Bauçà
- Research Group on Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears-INAGEAPalma de Mallorca, Spain
| | | | - Jeroni Galmés
- Research Group on Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears-INAGEAPalma de Mallorca, Spain
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19
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Kaiser E, Morales A, Harbinson J, Heuvelink E, Prinzenberg AE, Marcelis LFM. Metabolic and diffusional limitations of photosynthesis in fluctuating irradiance in Arabidopsis thaliana. Sci Rep 2016; 6:31252. [PMID: 27502328 PMCID: PMC4977489 DOI: 10.1038/srep31252] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 07/11/2016] [Indexed: 11/09/2022] Open
Abstract
A better understanding of the metabolic and diffusional limitations of photosynthesis in fluctuating irradiance can help identify targets for improving crop yields. We used different genotypes of Arabidopsis thaliana to characterise the importance of Rubisco activase (Rca), stomatal conductance (gs), non-photochemical quenching of chlorophyll fluorescence (NPQ) and sucrose phosphate synthase (SPS) on photosynthesis in fluctuating irradiance. Leaf gas exchange and chlorophyll fluorescence were measured in leaves exposed to stepwise increases and decreases in irradiance. rwt43, which has a constitutively active Rubisco enzyme in different irradiance intensities (except in darkness), showed faster increases than the wildtype, Colombia-0, in photosynthesis rates after step increases in irradiance. rca-2, having decreased Rca concentration, showed lower rates of increase. In aba2-1, high gs increased the rate of change after stepwise irradiance increases, while in C24, low gs tended to decrease it. Differences in rates of change between Colombia-0 and plants with low levels of NPQ (npq1-2, npq4-1) or SPS (spsa1) were negligible. In Colombia-0, the regulation of Rubisco activation and of gs were therefore limiting for photosynthesis in fluctuating irradiance, while levels of NPQ or SPS were not. This suggests Rca and gs as targets for improvement of photosynthesis of plants in fluctuating irradiance.
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Affiliation(s)
- Elias Kaiser
- Horticulture and Product Physiology Group, Department of Plant Sciences, Wageningen University, PO Box 16, 6700 AA Wageningen, The Netherlands
| | - Alejandro Morales
- Centre for Crop Systems Analysis, Department of Plant Sciences, Wageningen University, PO Box 430, 6700 AK Wageningen, The Netherlands
| | - Jeremy Harbinson
- Horticulture and Product Physiology Group, Department of Plant Sciences, Wageningen University, PO Box 16, 6700 AA Wageningen, The Netherlands
| | - Ep Heuvelink
- Horticulture and Product Physiology Group, Department of Plant Sciences, Wageningen University, PO Box 16, 6700 AA Wageningen, The Netherlands
| | - Aina E Prinzenberg
- Horticulture and Product Physiology Group, Department of Plant Sciences, Wageningen University, PO Box 16, 6700 AA Wageningen, The Netherlands.,Laboratory of Genetics, Department of Plant Sciences, Wageningen University, PO Box 16, 6700 AA Wageningen, The Netherlands
| | - Leo F M Marcelis
- Horticulture and Product Physiology Group, Department of Plant Sciences, Wageningen University, PO Box 16, 6700 AA Wageningen, The Netherlands
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20
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Sharwood RE, Sonawane BV, Ghannoum O, Whitney SM. Improved analysis of C4 and C3 photosynthesis via refined in vitro assays of their carbon fixation biochemistry. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:3137-48. [PMID: 27122573 PMCID: PMC4867899 DOI: 10.1093/jxb/erw154] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Plants operating C3 and C4 photosynthetic pathways exhibit differences in leaf anatomy and photosynthetic carbon fixation biochemistry. Fully understanding this underpinning biochemical variation is requisite to identifying solutions for improving photosynthetic efficiency and growth. Here we refine assay methods for accurately measuring the carboxylase and decarboxylase activities in C3 and C4 plant soluble protein. We show that differences in plant extract preparation and assay conditions are required to measure NADP-malic enzyme and phosphoenolpyruvate carboxylase (pH 8, Mg(2+), 22 °C) and phosphoenolpyruvate carboxykinase (pH 7, >2mM Mn(2+), no Mg(2+)) maximal activities accurately. We validate how the omission of MgCl2 during leaf protein extraction, lengthy (>1min) centrifugation times, and the use of non-pure ribulose-1,5-bisphosphate (RuBP) significantly underestimate Rubisco activation status. We show how Rubisco activation status varies with leaf ontogeny and is generally lower in mature C4 monocot leaves (45-60% activation) relative to C3 monocots (55-90% activation). Consistent with their >3-fold lower Rubisco contents, full Rubisco activation in soluble protein from C4 leaves (<5min) was faster than in C3 plant samples (<10min), with addition of Rubisco activase not required for full activation. We conclude that Rubisco inactivation in illuminated leaves primarily stems from RuBP binding to non-carbamylated enzyme, a state readily reversible by dilution during cellular protein extraction.
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Affiliation(s)
- Robert E Sharwood
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, Australian National University, Canberra ACT 2601, Australia
| | - Balasaheb V Sonawane
- ARC Centre of Excellence for Translational Photosynthesis, Hawkesbury Institute for the Environment, Western Sydney University, Richmond NSW 2753, Australia
| | - Oula Ghannoum
- ARC Centre of Excellence for Translational Photosynthesis, Hawkesbury Institute for the Environment, Western Sydney University, Richmond NSW 2753, Australia
| | - Spencer M Whitney
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, Australian National University, Canberra ACT 2601, Australia
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21
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Yan B, Wang X, Wang Z, Chen N, Mu C, Mao K, Han L, Zhang W, Liu H. Identification of potential cargo proteins of transportin protein AtTRN1 in Arabidopsis thaliana. PLANT CELL REPORTS 2016; 35:629-640. [PMID: 26650834 DOI: 10.1007/s00299-015-1908-4] [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: 05/25/2015] [Revised: 10/26/2015] [Accepted: 11/17/2015] [Indexed: 06/05/2023]
Abstract
We identified 23 novel proteins that can interact with At TRN1. These proteins are potential candidates of At TRN1 cargo proteins, which will facilitate our comprehending of At TRN1 functions in Arabidopsis. Tranportin 1 (TRN1) carries out the nucleo-cytoplasmic transport of many proteins, thereby ensuring that each of them is delivered to the right compartment for its proper function. These cargo proteins involved in lots of important processes, such as alternative pre-mRNA splicing, transcriptional regulation, and protein translation. Current understanding of cargo proteins transported by Arabidopsis thaliana transportin 1 (AtTRN1) is limited. Here, first we employed the yeast two-hybrid (Y2H) screening to identify proteins that can interact with AtTRN1 in Arabidopsis, and 12 novel proteins were found. Searching for PY-NLS motif in these 12 proteins suggested that no typical PY-NLS motif was present. We next investigated the specific motifs that will mediate the interactions in these sequences, and found that thirteen truncated fragments interacted with AtTRN1, containing 8 acidic and 5 basic fragments, respectively. We also searched the Arabidopsis proteome for homologs of cargo proteins of yeast Kapl04p and mammalian Kapβ2, and PY-NLS motif-containing proteins. Among these proteins, 11 were identified to interact with AtTRN1. The interactions between all the 23 proteins and AtTRN1 were confirmed by both Y2H and bimolecular fluorescence complementation (BiFC) assays. Our results show that AtTRN1 recognizes a broad spectrum of proteins having diverse functions, which will potentially be the cargoes of AtTRN1. Taken together, these results demonstrate the feasibility and potential power of these methods to identify cargo proteins of AtTRN1, and represent a primary and significant step in interpretation of AtTRN1 functionalities.
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Affiliation(s)
- Bo Yan
- Ministry Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China
| | - Xiaoning Wang
- Ministry Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China
| | - Zhenyu Wang
- Ministry Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China
| | - Ni Chen
- Ministry Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China
| | - Changjun Mu
- Ministry Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China
| | - Kaili Mao
- Ministry Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China
| | - Lirong Han
- Ministry Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China
| | - Wei Zhang
- Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai, 200444, People's Republic of China
| | - Heng Liu
- Ministry Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China.
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22
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Kim SY, Bender KW, Walker BJ, Zielinski RE, Spalding MH, Ort DR, Huber SC. The Plastid Casein Kinase 2 Phosphorylates Rubisco Activase at the Thr-78 Site but Is Not Essential for Regulation of Rubisco Activation State. FRONTIERS IN PLANT SCIENCE 2016; 7:404. [PMID: 27064346 PMCID: PMC4814456 DOI: 10.3389/fpls.2016.00404] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 03/16/2016] [Indexed: 05/05/2023]
Abstract
Rubisco activase (RCA) is essential for the activation of Rubisco, the carboxylating enzyme of photosynthesis. In Arabidopsis, RCA is composed of a large RCAα and small RCAβ isoform that are formed by alternative splicing of a single gene (At2g39730). The activity of Rubisco is controlled in response to changes in irradiance by regulation of RCA activity, which is known to involve a redox-sensitive disulfide bond located in the carboxy-terminal extension of the RCAα subunit. Additionally, phosphorylation of RCA threonine-78 (Thr-78) has been reported to occur in the dark suggesting that phosphorylation may also be associated with dark-inactivation of RCA and deactivation of Rubisco. In the present study, we developed site-specific antibodies to monitor phosphorylation of RCA at the Thr-78 site and used non-reducing SDS-PAGE to monitor the redox status of the RCAα subunit. By immunoblotting, phosphorylation of both RCA isoforms occurred at low light and in the dark and feeding peroxide or DTT to leaf segments indicated that redox status of the chloroplast stroma was a critical factor controlling RCA phosphorylation. Use of a knockout mutant identified the plastid-targeted casein kinase 2 (cpCK2α) as the major protein kinase involved in RCA phosphorylation. Studies with recombinant cpCK2α and synthetic peptide substrates identified acidic residues at the -1, +2, and +3 positions surrounding Thr-78 as strong positive recognition elements. The cpck2 knockout mutant had strongly reduced phosphorylation at the Thr-78 site but was similar to wild type plants in terms of induction kinetics of photosynthesis following transfer from darkness or low light to high light, suggesting that if phosphorylation of RCA Thr-78 plays a direct role it would be redundant to redox regulation for control of Rubisco activation state under normal conditions.
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Affiliation(s)
- Sang Y. Kim
- Global Change and Photosynthesis Research Unit, United States Department of Agriculture – Agricultural Research Service, UrbanaIL, USA
- Plant Biology, University of Illinois at Champaign–Urbana, UrbanaIL, USA
| | - Kyle W. Bender
- Plant Biology, University of Illinois at Champaign–Urbana, UrbanaIL, USA
| | - Berkley J. Walker
- Global Change and Photosynthesis Research Unit, United States Department of Agriculture – Agricultural Research Service, UrbanaIL, USA
- Carl R. Woese Institute for Genomic Biology, UrbanaIL, USA
| | | | - Martin H. Spalding
- Genetics, Development and Cell Biology, Iowa State University, AmesIA, USA
| | - Donald R. Ort
- Global Change and Photosynthesis Research Unit, United States Department of Agriculture – Agricultural Research Service, UrbanaIL, USA
- Plant Biology, University of Illinois at Champaign–Urbana, UrbanaIL, USA
- Carl R. Woese Institute for Genomic Biology, UrbanaIL, USA
| | - Steven C. Huber
- Global Change and Photosynthesis Research Unit, United States Department of Agriculture – Agricultural Research Service, UrbanaIL, USA
- Plant Biology, University of Illinois at Champaign–Urbana, UrbanaIL, USA
- *Correspondence: Steven C. Huber,
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Tsai YCC, Lapina MC, Bhushan S, Mueller-Cajar O. Identification and characterization of multiple rubisco activases in chemoautotrophic bacteria. Nat Commun 2015; 6:8883. [PMID: 26567524 PMCID: PMC4660213 DOI: 10.1038/ncomms9883] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 10/13/2015] [Indexed: 12/20/2022] Open
Abstract
Ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) is responsible for almost all biological CO2 assimilation, but forms inhibited complexes with its substrate ribulose-1,5-bisphosphate (RuBP) and other sugar phosphates. The distantly related AAA+ proteins rubisco activase and CbbX remodel inhibited rubisco complexes to effect inhibitor release in plants and α-proteobacteria, respectively. Here we characterize a third class of rubisco activase in the chemolithoautotroph Acidithiobacillus ferrooxidans. Two sets of isoforms of CbbQ and CbbO form hetero-oligomers that function as specific activases for two structurally diverse rubisco forms. Mutational analysis supports a model wherein the AAA+ protein CbbQ functions as motor and CbbO is a substrate adaptor that binds rubisco via a von Willebrand factor A domain. Understanding the mechanisms employed by nature to overcome rubisco's shortcomings will increase our toolbox for engineering photosynthetic carbon dioxide fixation. The CO2-fixing enzyme rubisco requires motor proteins known as rubisco activases to remove inhibitors bound to its active site. Here the authors describe a new class of rubisco activase present in chemoautotrophic bacteria that belongs to the MoxR family of AAA+ ATPases.
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Affiliation(s)
- Yi-Chin Candace Tsai
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551. Singapore
| | - Maria Claribel Lapina
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551. Singapore
| | - Shashi Bhushan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551. Singapore
| | - Oliver Mueller-Cajar
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551. Singapore
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Hazra S, Henderson JN, Liles K, Hilton MT, Wachter RM. Regulation of ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) activase: product inhibition, cooperativity, and magnesium activation. J Biol Chem 2015; 290:24222-36. [PMID: 26283786 PMCID: PMC4591810 DOI: 10.1074/jbc.m115.651745] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 08/04/2015] [Indexed: 12/24/2022] Open
Abstract
In many photosynthetic organisms, tight-binding Rubisco inhibitors are released by the motor protein Rubisco activase (Rca). In higher plants, Rca plays a pivotal role in regulating CO2 fixation. Here, the ATPase activity of 0.005 mm tobacco Rca was monitored under steady-state conditions, and global curve fitting was utilized to extract kinetic constants. The kcat was best fit by 22.3 ± 4.9 min(-1), the Km for ATP by 0.104 ± 0.024 mm, and the Ki for ADP by 0.037 ± 0.007 mm. Without ADP, the Hill coefficient for ATP hydrolysis was extracted to be 1.0 ± 0.1, indicating noncooperative behavior of homo-oligomeric Rca assemblies. However, the addition of ADP was shown to introduce positive cooperativity between two or more subunits (Hill coefficient 1.9 ± 0.2), allowing for regulation via the prevailing ATP/ADP ratio. ADP-mediated activation was not observed, although larger amounts led to competitive product inhibition of hydrolytic activity. The catalytic efficiency increased 8.4-fold upon cooperative binding of a second magnesium ion (Hill coefficient 2.5 ± 0.5), suggesting at least three conformational states (ATP-bound, ADP-bound, and empty) within assemblies containing an average of about six subunits. The addition of excess Rubisco (24:1, L8S8/Rca6) and crowding agents did not modify catalytic rates. However, high magnesium provided for thermal Rca stabilization. We propose that magnesium mediates the formation of closed hexameric toroids capable of high turnover rates and amenable to allosteric regulation. We suggest that in vivo, the Rca hydrolytic activity is tuned by fluctuating [Mg(2+)] in response to changes in available light.
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Affiliation(s)
- Suratna Hazra
- From the Department of Chemistry and Biochemistry and Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona 85287
| | - J Nathan Henderson
- From the Department of Chemistry and Biochemistry and Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona 85287
| | - Kevin Liles
- From the Department of Chemistry and Biochemistry and Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona 85287
| | - Matthew T Hilton
- From the Department of Chemistry and Biochemistry and Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona 85287
| | - Rebekka M Wachter
- From the Department of Chemistry and Biochemistry and Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona 85287
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25
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Carmo-Silva E, Scales JC, Madgwick PJ, Parry MAJ. Optimizing Rubisco and its regulation for greater resource use efficiency. PLANT, CELL & ENVIRONMENT 2015; 38:1817-32. [PMID: 25123951 DOI: 10.1111/pce.12425] [Citation(s) in RCA: 187] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 08/01/2014] [Accepted: 08/03/2014] [Indexed: 05/19/2023]
Abstract
Rubisco catalyses the carboxylation of ribulose-1,5-bisphosphate (RuBP), enabling net CO2 assimilation in photosynthesis. The properties and regulation of Rubisco are not optimal for biomass production in current and projected future environments. Rubisco is relatively inefficient, and large amounts of the enzyme are needed to support photosynthesis, requiring large investments in nitrogen. The competing oxygenation of RuBP by Rubisco decreases photosynthetic efficiency. Additionally, Rubisco is inhibited by some sugar phosphates and depends upon interaction with Rubisco activase (Rca) to be reactivated. Rca activity is modulated by the chloroplast redox status and ADP/ATP ratios, thereby mediating Rubisco activation and photosynthetic induction in response to irradiance. The extreme thermal sensitivity of Rca compromises net CO2 assimilation at moderately high temperatures. Given its central role in carbon assimilation, the improvement of Rubisco function and regulation is tightly linked with irradiance, nitrogen and water use efficiencies. Although past attempts have had limited success, novel technologies and an expanding knowledge base make the challenge of improving Rubisco activity in crops an achievable goal. Strategies to optimize Rubisco and its regulation are addressed in relation to their potential to improve crop resource use efficiency and climate resilience of photosynthesis.
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Affiliation(s)
| | - Joanna C Scales
- Plant Biology and Crop Science, Rothamsted Research, Harpenden, Herts, AL5 2JQ, UK
| | - Pippa J Madgwick
- Plant Biology and Crop Science, Rothamsted Research, Harpenden, Herts, AL5 2JQ, UK
| | - Martin A J Parry
- Plant Biology and Crop Science, Rothamsted Research, Harpenden, Herts, AL5 2JQ, UK
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26
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Kuriata AM, Chakraborty M, Henderson JN, Hazra S, Serban AJ, Pham TVT, Levitus M, Wachter RM. ATP and magnesium promote cotton short-form ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) activase hexamer formation at low micromolar concentrations. Biochemistry 2014; 53:7232-46. [PMID: 25357088 DOI: 10.1021/bi500968h] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We report a fluorescence correlation spectroscopy (FCS) study of the assembly pathway of the AAA+ protein ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) activase (Rca), a ring-forming ATPase responsible for activation of inhibited Rubisco complexes for biological carbon fixation. A thermodynamic characterization of simultaneously populated oligomeric states appears critical in understanding Rca structure and function. Using cotton β-Rca, we demonstrate that apparent diffusion coefficients vary as a function of concentration, nucleotide, and cation. Using manual fitting procedures, we provide estimates for the equilibrium constants for the stepwise assembly and find that in the presence of ATPγS, the Kd for hexamerization is 10-fold lower than with ADP (∼0.1 vs ∼1 μM). Hexamer fractions peak at 30 μM and dominate at 8-70 μM Rca, where they comprise 60-80% of subunits with ATPγS, compared with just 30-40% with ADP. Dimer fractions peak at 1-4 μM Rca, where they comprise 15-18% with ATPγS and 26-28% with ADP. At 30 μM Rca, large aggregates begin to form that comprise ∼10% of total protein with ATPγS and ∼25% with ADP. FCS data collected on the catalytically impaired WalkerB-D173N variant in the presence of ATP provided strong support for these results. Titration with free magnesium ions lead to the disaggregation of larger complexes in favor of hexameric forms, suggesting that a second magnesium binding site with a Kd value of 1-3 mM mediates critical subunit contacts. We propose that closed-ring toroidal hexameric forms are stabilized by binding of Mg·ATP plus Mg2+, whereas Mg·ADP promotes continuous assembly to supramolecular aggregates such as spirals.
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Affiliation(s)
- Agnieszka M Kuriata
- Department of Chemistry and Biochemistry and Center for Bioenergy and Photosynthesis, Arizona State University , Tempe, Arizona 85287, United States
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