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Tejera-Nieves M, Seong DY, Reist L, Walker BJ. The Dynamic Assimilation Technique measures photosynthetic CO2 response curves with similar fidelity to steady-state approaches in half the time. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2819-2828. [PMID: 38366564 PMCID: PMC11103103 DOI: 10.1093/jxb/erae057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 02/14/2024] [Indexed: 02/18/2024]
Abstract
The net CO2 assimilation (A) response to intercellular CO2 concentration (Ci) is a fundamental measurement in photosynthesis and plant physiology research. The conventional A/Ci protocols rely on steady-state measurements and take 15-40 min per measurement, limiting data resolution or biological replication. Additionally, there are several CO2 protocols employed across the literature, without clear consensus as to the optimal protocol or systematic biases in their estimations. We compared the non-steady-state Dynamic Assimilation Technique (DAT) protocol and the three most used CO2 protocols in steady-state measurements, and tested whether different CO2 protocols lead to systematic differences in estimations of the biochemical limitations to photosynthesis. The DAT protocol reduced the measurement time by almost half without compromising estimation accuracy or precision. The monotonic protocol was the fastest steady-state method. Estimations of biochemical limitations to photosynthesis were very consistent across all CO2 protocols, with slight differences in Rubisco carboxylation limitation. The A/Ci curves were not affected by the direction of the change of CO2 concentration but rather the time spent under triose phosphate utilization (TPU)-limited conditions. Our results suggest that the maximum rate of Rubisco carboxylation (Vcmax), linear electron flow for NADPH supply (J), and TPU measured using different protocols within the literature are comparable, or at least not systematically different based on the measurement protocol used.
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Affiliation(s)
- Mauricio Tejera-Nieves
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Rd, East Lansing, MI 48824, USA
- Great Lakes Bioenergy Research Center, Michigan State University, 1129 Farm Ln, East Lansing, MI 48824, USA
| | - Do Young Seong
- Department of Medical Informatics, College of Medicine, Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 06591, Republic of Korea
| | - Lucas Reist
- Department of Biochemistry & Molecular Biology, Michigan State University, Molecular Plant Sciences Building, 1066 Bogue Street, East Lansing, MI 48824, USA
| | - Berkley J Walker
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Rd, East Lansing, MI 48824, USA
- Great Lakes Bioenergy Research Center, Michigan State University, 1129 Farm Ln, East Lansing, MI 48824, USA
- Department of Plant Biology, Michigan State University, 612 Wilson Rd, East Lansing, MI 48824, USA
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2
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Roze LV, Johnson A, Walker BJ. High Throughput Glycerate Kinase Activity Assay Using Crude Leaf Extract and Recombinant Enzyme to Determine Kinetic Parameters K m and V max Using a Microplate Reader. Methods Mol Biol 2024; 2792:83-95. [PMID: 38861080 DOI: 10.1007/978-1-0716-3802-6_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
We describe an assay for measuring the activity of D-glycerate 3-kinase (GLYK) in a 96-well microplate format with the use of a set of coupling enzymes. The assay is appropriate for use with a crude protein extract prepared from leaf tissue and with the recombinant purified enzyme. The 96-well microplate format reduces the needed amounts of reagents and coupling enzymes, making the assay less expensive, high throughput, and suitable for the determination of kinetic parameters Km and Vmax. In addition, we provide a two-step discontinuous assay modified from past work, making it possible to measure the activity of GLYK at temperatures higher than 45 °C.
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Affiliation(s)
- Ludmila V Roze
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
| | - Audrey Johnson
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
| | - Berkley J Walker
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, USA.
- Department of Plant Biology, Michigan State University, East Lansing, MI, USA.
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, USA.
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3
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Gregory LM, Roze LV, Walker BJ. Increased activity of core photorespiratory enzymes and CO 2 transfer conductances are associated with higher and more optimal photosynthetic rates under elevated temperatures in the extremophile Rhazya stricta. PLANT, CELL & ENVIRONMENT 2023; 46:3704-3720. [PMID: 37667571 DOI: 10.1111/pce.14711] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 06/26/2023] [Accepted: 08/23/2023] [Indexed: 09/06/2023]
Abstract
Increase photorespiration and optimising intrinsic water use efficiency are unique challenges to photosynthetic carbon fixation at elevated temperatures. To determine how plants can adapt to facilitate high rates of photorespiration at elevated temperatures while also maintaining water-use efficiency, we performed in-depth gas exchange and biochemical assays of the C3 extremophile, Rhazya stricta. These results demonstrate that R. stricta supports higher rates of photorespiration under elevated temperatures and that these higher rates of photorespiration correlate with increased activity of key photorespiratory enzymes; phosphoglycolate phosphatase and catalase. The increased photorespiratory enzyme activities may increase the overall capacity of photorespiration by reducing enzymatic bottlenecks and allowing minimal inhibitor accumulation under high photorespiratory rates. Additionally, we found the CO2 transfer conductances (stomatal and mesophyll) are re-allocated to increase the water-use efficiency in R. stricta but not necessarily the photosynthetic response to temperature. These results suggest important adaptive strategies in R. stricta that maintain photosynthetic rates under elevated temperatures with optimal water loss. The strategies found in R. stricta may inform breeding and engineering efforts in other C3 species to improve photosynthetic efficiency at high temperatures.
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Affiliation(s)
- Luke M Gregory
- Department of Energy-Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
| | - Ludmila V Roze
- Department of Energy-Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
| | - Berkley J Walker
- Department of Energy-Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
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4
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Leisner CP, Potnis N, Sanz-Saez A. Crosstalk and trade-offs: Plant responses to climate change-associated abiotic and biotic stresses. PLANT, CELL & ENVIRONMENT 2023; 46:2946-2963. [PMID: 36585762 DOI: 10.1111/pce.14532] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/07/2022] [Accepted: 12/28/2022] [Indexed: 06/17/2023]
Abstract
As sessile organisms, plants are constantly challenged by a dynamic growing environment. This includes fluctuations in temperature, water availability, light levels, and changes in atmospheric constituents such as carbon dioxide (CO2 ) and ozone (O3 ). In concert with changes in abiotic conditions, plants experience changes in biotic stress pressures, including plant pathogens and herbivores. Human-induced increases in atmospheric CO2 levels have led to alterations in plant growth environments that impact their productivity and nutritional quality. Additionally, it is predicted that climate change will alter the prevalence and virulence of plant pathogens, further challenging plant growth. A knowledge gap exists in the complex interplay between plant responses to biotic and abiotic stress conditions. Closing this gap is crucial for developing climate resilient crops in the future. Here, we briefly review the physiological responses of plants to elevated CO2 , temperature, tropospheric O3 , and drought conditions, as well as the interaction of these abiotic stress factors with plant pathogen pressure. Additionally, we describe the crosstalk and trade-offs involved in plant responses to both abiotic and biotic stress, and outline targets for future work to develop a more sustainable future food supply considering future climate change.
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Affiliation(s)
- Courtney P Leisner
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - Neha Potnis
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Alvaro Sanz-Saez
- Department of Crop, Soil and Environmental Science, Auburn University, Auburn, Alabama, USA
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5
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Garcia A, Gaju O, Bowerman AF, Buck SA, Evans JR, Furbank RT, Gilliham M, Millar AH, Pogson BJ, Reynolds MP, Ruan Y, Taylor NL, Tyerman SD, Atkin OK. Enhancing crop yields through improvements in the efficiency of photosynthesis and respiration. THE NEW PHYTOLOGIST 2023; 237:60-77. [PMID: 36251512 PMCID: PMC10100352 DOI: 10.1111/nph.18545] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 09/15/2022] [Indexed: 06/06/2023]
Abstract
The rate with which crop yields per hectare increase each year is plateauing at the same time that human population growth and other factors increase food demand. Increasing yield potential (Y p ) of crops is vital to address these challenges. In this review, we explore a component ofY p that has yet to be optimised - that being improvements in the efficiency with which light energy is converted into biomass (ε c ) via modifications to CO2 fixed per unit quantum of light (α), efficiency of respiratory ATP production (ε prod ) and efficiency of ATP use (ε use ). For α, targets include changes in photoprotective machinery, ribulose bisphosphate carboxylase/oxygenase kinetics and photorespiratory pathways. There is also potential forε prod to be increased via targeted changes to the expression of the alternative oxidase and mitochondrial uncoupling pathways. Similarly, there are possibilities to improveε use via changes to the ATP costs of phloem loading, nutrient uptake, futile cycles and/or protein/membrane turnover. Recently developed high-throughput measurements of respiration can serve as a proxy for the cumulative energy cost of these processes. There are thus exciting opportunities to use our growing knowledge of factors influencing the efficiency of photosynthesis and respiration to create a step-change in yield potential of globally important crops.
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Affiliation(s)
- Andres Garcia
- ARC Centre of Excellence in Plant Energy Biology, Research School of BiologyThe Australian National UniversityCanberraACT2601Australia
- Division of Plant Sciences, Research School of BiologyAustralian National UniversityCanberraACT2601Australia
| | - Oorbessy Gaju
- ARC Centre of Excellence in Plant Energy Biology, Research School of BiologyThe Australian National UniversityCanberraACT2601Australia
- College of Science, Lincoln Institute for Agri‐Food TechnologyUniversity of LincolnLincolnshireLN2 2LGUK
| | - Andrew F. Bowerman
- ARC Centre of Excellence in Plant Energy Biology, Research School of BiologyThe Australian National UniversityCanberraACT2601Australia
- Division of Plant Sciences, Research School of BiologyAustralian National UniversityCanberraACT2601Australia
| | - Sally A. Buck
- ARC Centre of Excellence in Plant Energy Biology, Research School of BiologyThe Australian National UniversityCanberraACT2601Australia
- Division of Plant Sciences, Research School of BiologyAustralian National UniversityCanberraACT2601Australia
| | - John R. Evans
- Division of Plant Sciences, Research School of BiologyAustralian National UniversityCanberraACT2601Australia
- ARC Centre of Excellence for Translational Photosynthesis, Research School of BiologyThe Australian National UniversityCanberraACT2601Australia
| | - Robert T. Furbank
- Division of Plant Sciences, Research School of BiologyAustralian National UniversityCanberraACT2601Australia
- ARC Centre of Excellence for Translational Photosynthesis, Research School of BiologyThe Australian National UniversityCanberraACT2601Australia
| | - Matthew Gilliham
- ARC Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine & Waite Research InstituteUniversity of AdelaideGlen OsmondSA5064Australia
| | - A. Harvey Millar
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences & Institute of AgricultureThe University of Western AustraliaCrawleyWA6009Australia
| | - Barry J. Pogson
- ARC Centre of Excellence in Plant Energy Biology, Research School of BiologyThe Australian National UniversityCanberraACT2601Australia
- Division of Plant Sciences, Research School of BiologyAustralian National UniversityCanberraACT2601Australia
| | - Matthew P. Reynolds
- International Maize and Wheat Improvement Center (CIMMYT)Km. 45, Carretera Mexico, El BatanTexcoco56237Mexico
| | - Yong‐Ling Ruan
- Division of Plant Sciences, Research School of BiologyAustralian National UniversityCanberraACT2601Australia
| | - Nicolas L. Taylor
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences & Institute of AgricultureThe University of Western AustraliaCrawleyWA6009Australia
| | - Stephen D. Tyerman
- ARC Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine & Waite Research InstituteUniversity of AdelaideGlen OsmondSA5064Australia
| | - Owen K. Atkin
- ARC Centre of Excellence in Plant Energy Biology, Research School of BiologyThe Australian National UniversityCanberraACT2601Australia
- Division of Plant Sciences, Research School of BiologyAustralian National UniversityCanberraACT2601Australia
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6
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Cavanagh AP, South PF, Bernacchi CJ, Ort DR. Alternative pathway to photorespiration protects growth and productivity at elevated temperatures in a model crop. PLANT BIOTECHNOLOGY JOURNAL 2022; 20:711-721. [PMID: 34786804 PMCID: PMC8989507 DOI: 10.1111/pbi.13750] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/13/2021] [Accepted: 11/12/2021] [Indexed: 05/03/2023]
Abstract
Adapting crops to warmer growing season temperatures is a major challenge in mitigating the impacts of climate change on crop production. Warming temperatures drive greater evaporative demand and can directly interfere with both reproductive and vegetative physiological processes. Most of the world's crop species have C3 photosynthetic metabolism for which increasing temperature means higher rates of photorespiration, wherein the enzyme responsible for fixing CO2 fixes O2 instead followed by an energetically costly recycling pathway that spans several cell compartments. In C3 crops like wheat, rice and soybean, photorespiration translates into large yield losses that are predicted to increase as global temperature warms. Engineering less energy-intensive alternative photorespiratory pathways into crop chloroplasts drives increases in C3 biomass production under agricultural field conditions, but the efficacy of these pathways in mitigating the impact of warmer growing temperatures has not been tested. We grew tobacco plants expressing an alternative photorespiratory pathway under current and elevated temperatures (+5 °C) in agricultural field conditions. Engineered plants exhibited higher photosynthetic quantum efficiency under heated conditions than the control plants, and produced 26% (between 16% and 37%) more total biomass than WT plants under heated conditions, compared to 11% (between 5% and 17%) under ambient conditions. That is, engineered plants sustained 19% (between 11% and 21%) less yield loss under heated conditions compared to non-engineered plants. These results support the theoretical predictions of temperature impacts on photorespiratory losses and provide insight toward the optimisation strategies required to help sustain or improve C3 crop yields in a warming climate.
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Affiliation(s)
- Amanda P. Cavanagh
- Carl R. Woese Institute for Genomic BiologyUniversity of IllinoisUrbanaILUSA
- Present address:
School of Life SciencesUniversity of EssexColchesterUK
| | - Paul F. South
- Carl R. Woese Institute for Genomic BiologyUniversity of IllinoisUrbanaILUSA
- Global Change and Photosynthesis Research UnitUnited States Department of Agriculture–Agricultural Research ServiceUrbanaILUSA
- Present address:
Department of Biological SciencesLouisiana State UniversityBaton RougeLAUSA
| | - Carl J. Bernacchi
- Carl R. Woese Institute for Genomic BiologyUniversity of IllinoisUrbanaILUSA
- Global Change and Photosynthesis Research UnitUnited States Department of Agriculture–Agricultural Research ServiceUrbanaILUSA
| | - Donald R. Ort
- Carl R. Woese Institute for Genomic BiologyUniversity of IllinoisUrbanaILUSA
- Departments of Plant Biology and Crop SciencesUniversity of IllinoisUrbanaILUSA
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7
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Verma V, Vishal B, Kohli A, Kumar PP. Systems-based rice improvement approaches for sustainable food and nutritional security. PLANT CELL REPORTS 2021; 40:2021-2036. [PMID: 34591154 DOI: 10.1007/s00299-021-02790-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 09/15/2021] [Indexed: 06/13/2023]
Abstract
An integrated research approach to ensure sustainable rice yield increase of a crop grown by 25% of the world's farmers in 10% of cropland is essential for global food security. Rice, being a global staple crop, feeds about 56% of the world population and sustains 40% of the world's poor. At ~ $200 billion, it also accounts for 13% of the annual crop value. With hunger and malnutrition rampant among the poor, rice research for development is unique in global food and nutrition security. A systems-based, sustainable increase in rice quantity and quality is imperative for environmental and biodiversity benefits. Upstream 'discovery' through biotechnology, midstream 'development' through breeding and agronomy, downstream 'dissemination and deployment' must be 'demand-driven' for 'distinct socio-economic transformational impacts'. Local agro-ecology and livelihood nexus must drive the research agenda for targeted benefits. This necessitates sustained long-term investments by government, non-government and private sectors to secure the future food, nutrition, environment, prosperity and equity status.
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Affiliation(s)
- Vivek Verma
- Department of Biotechnology, School of Life Sciences, Central University of Rajasthan, Ajmer, 305817, Rajasthan, India.
| | - Bhushan Vishal
- School of Biological Sciences, Nanyang Technological University, Singapore, 639798, Republic of Singapore
| | - Ajay Kohli
- Strategic Innovation Platform, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines
| | - Prakash P Kumar
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, 117543, Republic of Singapore.
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8
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Anderson CM, Mattoon EM, Zhang N, Becker E, McHargue W, Yang J, Patel D, Dautermann O, McAdam SAM, Tarin T, Pathak S, Avenson TJ, Berry J, Braud M, Niyogi KK, Wilson M, Nusinow DA, Vargas R, Czymmek KJ, Eveland AL, Zhang R. High light and temperature reduce photosynthetic efficiency through different mechanisms in the C 4 model Setaria viridis. Commun Biol 2021; 4:1092. [PMID: 34531541 PMCID: PMC8446033 DOI: 10.1038/s42003-021-02576-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Accepted: 08/03/2021] [Indexed: 11/09/2022] Open
Abstract
C4 plants frequently experience high light and high temperature conditions in the field, which reduce growth and yield. However, the mechanisms underlying these stress responses in C4 plants have been under-explored, especially the coordination between mesophyll (M) and bundle sheath (BS) cells. We investigated how the C4 model plant Setaria viridis responded to a four-hour high light or high temperature treatment at photosynthetic, transcriptomic, and ultrastructural levels. Although we observed a comparable reduction of photosynthetic efficiency in high light or high temperature treated leaves, detailed analysis of multi-level responses revealed important differences in key pathways and M/BS specificity responding to high light and high temperature. We provide a systematic analysis of high light and high temperature responses in S. viridis, reveal different acclimation strategies to these two stresses in C4 plants, discover unique light/temperature responses in C4 plants in comparison to C3 plants, and identify potential targets to improve abiotic stress tolerance in C4 crops.
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Affiliation(s)
| | - Erin M Mattoon
- Donald Danforth Plant Science Center, St. Louis, MO, USA.,Plant and Microbial Biosciences Program, Division of Biology and Biomedical Sciences, Washington University in Saint Louis, St. Louis, MO, USA
| | - Ningning Zhang
- Donald Danforth Plant Science Center, St. Louis, MO, USA
| | - Eric Becker
- Donald Danforth Plant Science Center, St. Louis, MO, USA
| | | | - Jiani Yang
- Donald Danforth Plant Science Center, St. Louis, MO, USA
| | - Dhruv Patel
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - Oliver Dautermann
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - Scott A M McAdam
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, USA
| | - Tonantzin Tarin
- Department of Plant and Soil Sciences, University of Delaware, Newark, DE, USA.,Instituto de Ecología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Sunita Pathak
- Donald Danforth Plant Science Center, St. Louis, MO, USA
| | - Tom J Avenson
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
| | - Jeffrey Berry
- Donald Danforth Plant Science Center, St. Louis, MO, USA
| | - Maxwell Braud
- Donald Danforth Plant Science Center, St. Louis, MO, USA
| | - Krishna K Niyogi
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.,Howard Hughes Medical Institute, Berkeley, CA, USA.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | | | | | - Rodrigo Vargas
- Department of Plant and Soil Sciences, University of Delaware, Newark, DE, USA
| | - Kirk J Czymmek
- Donald Danforth Plant Science Center, St. Louis, MO, USA
| | | | - Ru Zhang
- Donald Danforth Plant Science Center, St. Louis, MO, USA.
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9
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Abstract
Most secondary nonphotosynthetic eukaryotes have retained residual plastids whose physiological role is often still unknown. One such example is Euglena longa, a close nonphotosynthetic relative of Euglena gracilis harboring a plastid organelle of enigmatic function. By mining transcriptome data from E. longa, we finally provide an overview of metabolic processes localized to its elusive plastid. The organelle plays no role in the biosynthesis of isoprenoid precursors and fatty acids and has a very limited repertoire of pathways concerning nitrogen-containing metabolites. In contrast, the synthesis of phospholipids and glycolipids has been preserved, curiously with the last step of sulfoquinovosyldiacylglycerol synthesis being catalyzed by the SqdX form of an enzyme so far known only from bacteria. Notably, we show that the E. longa plastid synthesizes tocopherols and a phylloquinone derivative, the first such report for nonphotosynthetic plastids studied so far. The most striking attribute of the organelle could be the presence of a linearized Calvin-Benson (CB) pathway, including RuBisCO yet lacking the gluconeogenetic part of the standard cycle, together with ferredoxin-NADP+ reductase (FNR) and the ferredoxin/thioredoxin system. We hypothesize that the ferredoxin/thioredoxin system activates the linear CB pathway in response to the redox status of the E. longa cell and speculate on the role of the pathway in keeping the redox balance of the cell. Altogether, the E. longa plastid defines a new class of relic plastids that is drastically different from the best-studied organelle of this category, the apicoplast.IMPORTANCE Colorless plastids incapable of photosynthesis evolved in many plant and algal groups, but what functions they perform is still unknown in many cases. Here, we study the elusive plastid of Euglena longa, a nonphotosynthetic cousin of the familiar green flagellate Euglena gracilis We document an unprecedented combination of metabolic functions that the E. longa plastid exhibits in comparison with previously characterized nonphotosynthetic plastids. For example, and truly surprisingly, it has retained the synthesis of tocopherols (vitamin E) and a phylloquinone (vitamin K) derivative. In addition, we offer a possible solution of the long-standing conundrum of the presence of the CO2-fixing enzyme RuBisCO in E. longa Our work provides a detailed account on a unique variant of relic plastids, the first among nonphotosynthetic plastids that evolved by secondary endosymbiosis from a green algal ancestor, and suggests that it has persisted for reasons not previously considered in relation to nonphotosynthetic plastids.
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10
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Timm S, Hagemann M. Photorespiration-how is it regulated and how does it regulate overall plant metabolism? JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:3955-3965. [PMID: 32274517 DOI: 10.1093/jxb/eraa183] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 04/08/2020] [Indexed: 05/03/2023]
Abstract
Under the current atmospheric conditions, oxygenic photosynthesis requires photorespiration to operate. In the presence of low CO2/O2 ratios, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) performs an oxygenase side reaction, leading to the formation of high amounts of 2-phosphoglycolate during illumination. Given that 2-phosphoglycolate is a potent inhibitor of photosynthetic carbon fixation, it must be immediately removed through photorespiration. The core photorespiratory cycle is orchestrated across three interacting subcellular compartments, namely chloroplasts, peroxisomes, and mitochondria, and thus cross-talks with a multitude of other cellular processes. Over the past years, the metabolic interaction of photorespiration and photosynthetic CO2 fixation has attracted major interest because research has demonstrated the enhancement of C3 photosynthesis and growth through the genetic manipulation of photorespiration. However, to optimize future engineering approaches, it is also essential to improve our current understanding of the regulatory mechanisms of photorespiration. Here, we summarize recent progress regarding the steps that control carbon flux in photorespiration, eventually involving regulatory proteins and metabolites. In this regard, both genetic engineering and the identification of various layers of regulation point to glycine decarboxylase as the key enzyme to regulate and adjust the photorespiratory carbon flow. Potential implications of the regulation of photorespiration for acclimation to environmental changes along with open questions are also discussed.
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Affiliation(s)
- Stefan Timm
- University of Rostock, Plant Physiology Department, Rostock, Germany
| | - Martin Hagemann
- University of Rostock, Plant Physiology Department, Rostock, Germany
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11
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Rodrigues DA, Sales JDF, Vasconcelos Filho SC, Rodrigues AA, Guimarães Teles EM, Costa AC, Reis EL, Andrade de Carvalho Silva T, Müller C. Bioindicator potential of Ricinus communis to simulated rainfall containing potassium fluoride. PeerJ 2020; 8:e9445. [PMID: 32676226 PMCID: PMC7334979 DOI: 10.7717/peerj.9445] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 06/08/2020] [Indexed: 01/29/2023] Open
Abstract
Background Fluoride pollution is a global problem because of its high phytotoxicity. Fluoride is released in air, water and soil through industrial processes, where it damages various plant species. Ricinus communis is widely distributed in Brazil, India and China and has been extensively used as a phytoremediation species in heavy metal-contaminated soils. However, few studies regarding the effect of air pollutants on R. communis have been published, and no information about the exposure of this species to fluoride is available. Therefore, the aim of the present study was to investigate the effects of fluoride on R. communis morphoanatomical and physiological responses using simulated rainfall containing potassium fluoride (KF). Methods Young plants at approximately 10 days after emergence were treated daily with KF using simulated rainfall at 0, 1.5, 3.0 and 4.5 mg L−1, for 37 consecutive days. Chlorophyll a fluorescence, gas exchange, anatomical characteristics and fluoride accumulation in the roots and leaves were evaluated after this period. Results No visual or anatomical symptoms were observed for the first three treatments. Necrosis and chlorosis were visually evident after the 37th day of KF application at 4.5 mg L−1, followed by changes in parenchyma tissues, cell collapse and phenolic compound accumulation at the end of the experiment. No damage was observed in terms of photosynthetic photochemical and biochemical stages. Maintenance of physiological characteristics in the presence of fluoride accumulation in roots and leaves were shown to be important fluoride biomarkers. These characteristics suggest that R. communis is tolerant to 1.5 and 3.0 mg L−1 KF, and is anatomically sensitive at 4.5 mg L−1 KF.
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Affiliation(s)
- Douglas Almeida Rodrigues
- Laboratory of Seeds, Goiano Federal Institute of Education, Science and Technology, Rio Verde, Goiás, Brazil.,Laboratory of Plant Anatomy, Goiano Federal Institute of Education, Science and Technology, Rio Verde, Goiás, Brazil
| | - Juliana de Fátima Sales
- Laboratory of Seeds, Goiano Federal Institute of Education, Science and Technology, Rio Verde, Goiás, Brazil
| | | | - Arthur Almeida Rodrigues
- Laboratory of Seeds, Goiano Federal Institute of Education, Science and Technology, Rio Verde, Goiás, Brazil.,Laboratory of Plant Anatomy, Goiano Federal Institute of Education, Science and Technology, Rio Verde, Goiás, Brazil
| | | | - Alan Carlos Costa
- Laboratory of Ecophysiology and Plant Productivity, Goiano Federal Institute of Education, Science and Technology, Rio Verde, Goiás, Brazil
| | - Efraim Lázaro Reis
- Department of Chemistry, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil
| | | | - Caroline Müller
- Laboratory of Ecophysiology and Plant Productivity, Goiano Federal Institute of Education, Science and Technology, Rio Verde, Goiás, Brazil
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12
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da Silva Cabral de Moraes JR, Souza Rolim GD, Martorano LG, de Oliveira Aparecido LE, Padilha de Oliveira MDS, de Farias Neto JT. Agrometeorological models to forecast açaí (Euterpe oleracea Mart.) yield in the Eastern Amazon. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2020; 100:1558-1569. [PMID: 31769034 DOI: 10.1002/jsfa.10164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 11/20/2019] [Accepted: 11/21/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND The increasing demand in Brazil and the world for products derived from the açaí palm (Euterpe oleracea Mart) has generated changes in its production process, principally due to the necessity of maintaining yield in situations of seasonality and climate fluctuation. The objective of this study was to estimate açaí fruit yield in irrigated system (IRRS) and rainfed system or unirrigated (RAINF) using agrometeorological models in response to climate conditions in the eastern Amazon. Modeling was done using multiple linear regression using the 'stepwise forward' method of variable selection. Monthly air temperature (T) values, solar radiation (SR), vapor pressure deficit (VPD), precipitation + irrigation (P + I), and potential evapotranspiration (PET) in six phenological phases were correlated with yield. The thermal necessity value was calculated through the sum of accumulated degree days (ADD) up to the formation of fruit bunch, as well as the time necessary for initial leaf development, using a base temperature of 10 °C. RESULTS The most important meteorological variables were T, SR, and VPD for IRRS, and for RAINF water stress had the greatest effect. The accuracy of the agrometeorological models, using maximum values for mean absolute percent error (MAPE), was 0.01 in the IRRS and 1.12 in the RAINF. CONCLUSION Using these models yield was predicted approximately 6 to 9 months before the harvest, in April, May, November, and December in the IRRS, and January, May, June, August, September, and November for the RAINF. © 2019 Society of Chemical Industry.
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Affiliation(s)
| | - Glauco de Souza Rolim
- School of Agricultural and Veterinarian Sciences, São Paulo State University (UNESP), Jaboticabal, Brazil
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Simkin AJ. Genetic Engineering for Global Food Security: Photosynthesis and Biofortification. PLANTS (BASEL, SWITZERLAND) 2019; 8:E586. [PMID: 31835394 PMCID: PMC6963231 DOI: 10.3390/plants8120586] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 12/04/2019] [Accepted: 12/05/2019] [Indexed: 12/18/2022]
Abstract
Increasing demands for food and resources are challenging existing markets, driving a need to continually investigate and establish crop varieties with improved yields and health benefits. By the later part of the century, current estimates indicate that a >50% increase in the yield of most of the important food crops including wheat, rice and barley will be needed to maintain food supplies and improve nutritional quality to tackle what has become known as 'hidden hunger'. Improving the nutritional quality of crops has become a target for providing the micronutrients required in remote communities where dietary variation is often limited. A number of methods to achieve this have been investigated over recent years, from improving photosynthesis through genetic engineering, to breeding new higher yielding varieties. Recent research has shown that growing plants under elevated [CO2] can lead to an increase in Vitamin C due to changes in gene expression, demonstrating one potential route for plant biofortification. In this review, we discuss the current research being undertaken to improve photosynthesis and biofortify key crops to secure future food supplies and the potential links between improved photosynthesis and nutritional quality.
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Affiliation(s)
- Andrew John Simkin
- Genetics, Genomics and Breeding, NIAB EMR, East Malling, Kent, ME19 6BJ, UK
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14
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Simkin AJ, López-Calcagno PE, Raines CA. Feeding the world: improving photosynthetic efficiency for sustainable crop production. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:1119-1140. [PMID: 30772919 PMCID: PMC6395887 DOI: 10.1093/jxb/ery445] [Citation(s) in RCA: 213] [Impact Index Per Article: 42.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 11/27/2018] [Indexed: 05/18/2023]
Abstract
A number of recent studies have provided strong support demonstrating that improving the photosynthetic processes through genetic engineering can provide an avenue to improve yield potential. The major focus of this review is on improvement of the Calvin-Benson cycle and electron transport. Consideration is also given to how altering regulatory process may provide an additional route to increase photosynthetic efficiency. Here we summarize some of the recent successes that have been observed through genetic manipulation of photosynthesis, showing that, in both the glasshouse and the field, yield can be increased by >40%. These results provide a clear demonstration of the potential for increasing yield through improvements in photosynthesis. In the final section, we consider the need to stack improvement in photosynthetic traits with traits that target the yield gap in order to provide robust germplasm for different crops across the globe.
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Affiliation(s)
- Andrew J Simkin
- NIAB EMR, New Road, East Malling, Kent, UK
- School of Biological Sciences, Wivenhoe Park, University of Essex, Colchester, UK
| | | | - Christine A Raines
- School of Biological Sciences, Wivenhoe Park, University of Essex, Colchester, UK
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15
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Li J, Tietz S, Cruz JA, Strand DD, Xu Y, Chen J, Kramer DM, Hu J. Photometric screens identified Arabidopsis peroxisome proteins that impact photosynthesis under dynamic light conditions. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 97:460-474. [PMID: 30350901 DOI: 10.1111/tpj.14134] [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: 06/26/2018] [Revised: 10/14/2018] [Accepted: 10/17/2018] [Indexed: 05/02/2023]
Abstract
Plant peroxisomes function collaboratively with other subcellular organelles, such as chloroplasts and mitochondria, in several metabolic processes. To comprehensively investigate the impact of peroxisomal function on photosynthesis, especially under conditions that are more relevant to natural environments, a systematic screen of over 150 Arabidopsis mutants of genes encoding peroxisomal proteins was conducted using the automated Dynamic Environment Photosynthesis Imager (DEPI). Dynamic and high-light (HL) conditions triggered significant photosynthetic defects in a subset of the mutants, including those of photorespiration (PR) and other peroxisomal processes, some of which may also be related to PR. Further analysis of the PR mutants revealed activation of cyclic electron flow (CEF) around photosystem I and higher accumulation of hydrogen peroxide (H2 O2 ) under HL conditions. We hypothesize that impaired PR disturbs the balance of ATP and NADPH, leading to the accumulation of H2 O2 that activates CEF to produce ATP to compensate for the imbalance of reducing equivalents. The identification of peroxisomal mutants involved in PR and other peroxisomal functions in the photometric screen will enable further investigation of regulatory links between photosynthesis and PR and interorganellar interaction at the mechanistic level.
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Affiliation(s)
- Jiying Li
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, 48824, USA
| | - Stefanie Tietz
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, 48824, USA
| | - Jeffrey A Cruz
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, 48824, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Deserah D Strand
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, 48824, USA
| | - Ye Xu
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, 48824, USA
| | - Jin Chen
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, 48824, USA
- Department of Computer Science and Engineering, Michigan State University, East Lansing, MI, 48824, USA
| | - David M Kramer
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, 48824, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Jianping Hu
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, 48824, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI, 48824, USA
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16
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South PF, Cavanagh AP, Liu HW, Ort DR. Synthetic glycolate metabolism pathways stimulate crop growth and productivity in the field. Science 2019; 363:eaat9077. [PMID: 30606819 PMCID: PMC7745124 DOI: 10.1126/science.aat9077] [Citation(s) in RCA: 324] [Impact Index Per Article: 64.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 11/20/2018] [Indexed: 01/06/2023]
Abstract
Photorespiration is required in C3 plants to metabolize toxic glycolate formed when ribulose-1,5-bisphosphate carboxylase-oxygenase oxygenates rather than carboxylates ribulose-1,5-bisphosphate. Depending on growing temperatures, photorespiration can reduce yields by 20 to 50% in C3 crops. Inspired by earlier work, we installed into tobacco chloroplasts synthetic glycolate metabolic pathways that are thought to be more efficient than the native pathway. Flux through the synthetic pathways was maximized by inhibiting glycolate export from the chloroplast. The synthetic pathways tested improved photosynthetic quantum yield by 20%. Numerous homozygous transgenic lines increased biomass productivity by >40% in replicated field trials. These results show that engineering alternative glycolate metabolic pathways into crop chloroplasts while inhibiting glycolate export into the native pathway can drive increases in C3 crop yield under agricultural field conditions.
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Affiliation(s)
- Paul F South
- Global Change and Photosynthesis Research Unit, United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA
| | - Amanda P Cavanagh
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA
| | - Helen W Liu
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801, USA
| | - Donald R Ort
- Global Change and Photosynthesis Research Unit, United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801, USA.
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801, USA
- Department of Plant Biology, University of Illinois, Urbana, IL 61801, USA
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17
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Selinski J, Scheibe R. Malate valves: old shuttles with new perspectives. PLANT BIOLOGY (STUTTGART, GERMANY) 2019; 21 Suppl 1:21-30. [PMID: 29933514 PMCID: PMC6586076 DOI: 10.1111/plb.12869] [Citation(s) in RCA: 117] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 06/18/2018] [Indexed: 05/18/2023]
Abstract
Malate valves act as powerful systems for balancing the ATP/NAD(P)H ratio required in various subcellular compartments in plant cells. As components of malate valves, isoforms of malate dehydrogenases (MDHs) and dicarboxylate translocators catalyse the reversible interconversion of malate and oxaloacetate and their transport. Depending on the co-enzyme specificity of the MDH isoforms, either NADH or NADPH can be transported indirectly. Arabidopsis thaliana possesses nine genes encoding MDH isoenzymes. Activities of NAD-dependent MDHs have been detected in mitochondria, peroxisomes, cytosol and plastids. In addition, chloroplasts possess a NADP-dependent MDH isoform. The NADP-MDH as part of the 'light malate valve' plays an important role as a poising mechanism to adjust the ATP/NADPH ratio in the stroma. Its activity is strictly regulated by post-translational redox-modification mediated via the ferredoxin-thioredoxin system and fine control via the NADP+ /NADP(H) ratio, thereby maintaining redox homeostasis under changing conditions. In contrast, the plastid NAD-MDH ('dark malate valve') is constitutively active and its lack leads to failure in early embryo development. While redox regulation of the main cytosolic MDH isoform has been shown, knowledge about regulation of the other two cytosolic MDHs as well as NAD-MDH isoforms from peroxisomes and mitochondria is still lacking. Knockout mutants lacking the isoforms from chloroplasts, mitochondria and peroxisomes have been characterised, but not much is known about cytosolic NAD-MDH isoforms and their role in planta. This review updates the current knowledge on MDH isoforms and the shuttle systems for intercompartmental dicarboxylate exchange, focusing on the various metabolic functions of these valves.
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Affiliation(s)
- J. Selinski
- Department of Animal, Plant, and Soil ScienceAustralian Research Council Centre of Excellence in Plant Energy BiologySchool of Life ScienceLa Trobe University BundooraBundooraAustralia
| | - R. Scheibe
- Division of Plant PhysiologyDepartment of Biology/ChemistryUniversity of OsnabrueckOsnabrueckGermany
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South PF, Cavanagh AP, Lopez-Calcagno PE, Raines CA, Ort DR. Optimizing photorespiration for improved crop productivity. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2018; 60:1217-1230. [PMID: 30126060 DOI: 10.1111/jipb.12709] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 08/14/2018] [Indexed: 05/24/2023]
Abstract
In C3 plants, photorespiration is an energy-expensive process, including the oxygenation of ribulose-1,5-bisphosphate (RuBP) by ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) and the ensuing multi-organellar photorespiratory pathway required to recycle the toxic byproducts and recapture a portion of the fixed carbon. Photorespiration significantly impacts crop productivity through reducing yields in C3 crops by as much as 50% under severe conditions. Thus, reducing the flux through, or improving the efficiency of photorespiration has the potential of large improvements in C3 crop productivity. Here, we review an array of approaches intended to engineer photorespiration in a range of plant systems with the goal of increasing crop productivity. Approaches include optimizing flux through the native photorespiratory pathway, installing non-native alternative photorespiratory pathways, and lowering or even eliminating Rubisco-catalyzed oxygenation of RuBP to reduce substrate entrance into the photorespiratory cycle. Some proposed designs have been successful at the proof of concept level. A plant systems-engineering approach, based on new opportunities available from synthetic biology to implement in silico designs, holds promise for further progress toward delivering more productive crops to farmer's fields.
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Affiliation(s)
- Paul F South
- Global Change and Photosynthesis Research Unit, United States Department of Agriculture/Agricultural Research Service, Urbana, IL 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA
| | - Amanda P Cavanagh
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA
| | | | - Christine A Raines
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - Donald R Ort
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801, USA
- Department of Plant Biology, University of Illinois, Urbana, IL 61801, USA
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19
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Messant M, Timm S, Fantuzzi A, Weckwerth W, Bauwe H, Rutherford AW, Krieger-Liszkay A. Glycolate Induces Redox Tuning Of Photosystem II in Vivo: Study of a Photorespiration Mutant. PLANT PHYSIOLOGY 2018; 177:1277-1285. [PMID: 29794021 PMCID: PMC6053007 DOI: 10.1104/pp.18.00341] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 05/09/2018] [Indexed: 05/03/2023]
Abstract
Bicarbonate removal from the nonheme iron at the acceptor side of photosystem II (PSII) was shown recently to shift the midpoint potential of the primary quinone acceptor QA to a more positive potential and lowers the yield of singlet oxygen (1O2) production. The presence of QA- results in weaker binding of bicarbonate, suggesting a redox-based regulatory and protective mechanism where loss of bicarbonate or exchange of bicarbonate by other small carboxylic acids may protect PSII against 1O2 in vivo under photorespiratory conditions. Here, we compared the properties of QA in the Arabidopsis (Arabidopsis thaliana) photorespiration mutant deficient in peroxisomal HYDROXYPYRUVATE REDUCTASE1 (hpr1-1), which accumulates glycolate in leaves, with the wild type. Photosynthetic electron transport was affected in the mutant, and chlorophyll fluorescence showed slower electron transport between QA and QB in the mutant. Glycolate induced an increase in the temperature maximum of thermoluminescence emission, indicating a shift of the midpoint potential of QA to a more positive value. The yield of 1O2 production was lowered in thylakoid membranes isolated from hpr1-1 compared with the wild type, consistent with a higher potential of QA/QA- In addition, electron donation to photosystem I was affected in hpr1-1 at higher light intensities, consistent with diminished electron transfer out of PSII. This study indicates that replacement of bicarbonate at the nonheme iron by a small carboxylate anion occurs in plants in vivo. These findings suggested that replacement of the bicarbonate on the nonheme iron by glycolate may represent a regulatory mechanism that protects PSII against photooxidative stress under low-CO2 conditions.
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Affiliation(s)
- Marine Messant
- Institute for Integrative Biology of the Cell, Commissariat à l'Energie Atomique, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, F-91198 Gif-sur-Yvette cedex, France
| | - Stefan Timm
- University of Rostock, Plant Physiology Department, D-18051 Rostock, Germany
| | - Andrea Fantuzzi
- Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Wolfram Weckwerth
- Department of Ecogenomics and Systems Biology, University of Vienna, Vienna 1090, Austria
- Vienna Metabolomics Center, University of Vienna, Vienna 1090, Austria
| | - Hermann Bauwe
- University of Rostock, Plant Physiology Department, D-18051 Rostock, Germany
| | - A William Rutherford
- Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Anja Krieger-Liszkay
- Institute for Integrative Biology of the Cell, Commissariat à l'Energie Atomique, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, F-91198 Gif-sur-Yvette cedex, France
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20
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Abadie C, Bathellier C, Tcherkez G. Carbon allocation to major metabolites in illuminated leaves is not just proportional to photosynthesis when gaseous conditions (CO 2 and O 2 ) vary. THE NEW PHYTOLOGIST 2018; 218:94-106. [PMID: 29344970 DOI: 10.1111/nph.14984] [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: 10/06/2017] [Accepted: 11/29/2017] [Indexed: 06/07/2023]
Abstract
In gas-exchange experiments, manipulating CO2 and O2 is commonly used to change the balance between carboxylation and oxygenation. Downstream metabolism (utilization of photosynthetic and photorespiratory products) may also be affected by gaseous conditions but this is not well documented. Here, we took advantage of sunflower as a model species, which accumulates chlorogenate in addition to sugars and amino acids (glutamate, alanine, glycine and serine). We performed isotopic labelling with 13 CO2 under different CO2 /O2 conditions, and determined 13 C contents to compute 13 C-allocation patterns and build-up rates. The 13 C content in major metabolites was not found to be a constant proportion of net fixed carbon but, rather, changed dramatically with CO2 and O2 . Alanine typically accumulated at low O2 (hypoxic response) while photorespiratory intermediates accumulated under ambient conditions and at high photorespiration, glycerate accumulation exceeding serine and glycine build-up. Chlorogenate synthesis was relatively more important under normal conditions and at high CO2 and its synthesis was driven by phosphoenolpyruvate de novo synthesis. These findings demonstrate that carbon allocation to metabolites other than photosynthetic end products is affected by gaseous conditions and therefore the photosynthetic yield of net nitrogen assimilation varies, being minimal at high CO2 and maximal at high O2 .
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Affiliation(s)
- Cyril Abadie
- Research School of Biology, College of Science, Australian National University, 2601, Canberra, ACT, Australia
| | - Camille Bathellier
- Research School of Biology, College of Science, Australian National University, 2601, Canberra, ACT, Australia
| | - Guillaume Tcherkez
- Research School of Biology, College of Science, Australian National University, 2601, Canberra, ACT, Australia
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21
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Simkin AJ, Lopez‐Calcagno PE, Davey PA, Headland LR, Lawson T, Timm S, Bauwe H, Raines CA. Simultaneous stimulation of sedoheptulose 1,7-bisphosphatase, fructose 1,6-bisphophate aldolase and the photorespiratory glycine decarboxylase-H protein increases CO 2 assimilation, vegetative biomass and seed yield in Arabidopsis. PLANT BIOTECHNOLOGY JOURNAL 2017; 15:805-816. [PMID: 27936496 PMCID: PMC5466442 DOI: 10.1111/pbi.12676] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 11/25/2016] [Accepted: 11/30/2016] [Indexed: 05/18/2023]
Abstract
In this article, we have altered the levels of three different enzymes involved in the Calvin-Benson cycle and photorespiratory pathway. We have generated transgenic Arabidopsis plants with altered combinations of sedoheptulose 1,7-bisphosphatase (SBPase), fructose 1,6-bisphophate aldolase (FBPA) and the glycine decarboxylase-H protein (GDC-H) gene identified as targets to improve photosynthesis based on previous studies. Here, we show that increasing the levels of the three corresponding proteins, either independently or in combination, significantly increases the quantum efficiency of PSII. Furthermore, photosynthetic measurements demonstrated an increase in the maximum efficiency of CO2 fixation in lines over-expressing SBPase and FBPA. Moreover, the co-expression of GDC-H with SBPase and FBPA resulted in a cumulative positive impact on leaf area and biomass. Finally, further analysis of transgenic lines revealed a cumulative increase of seed yield in SFH lines grown in high light. These results demonstrate the potential of multigene stacking for improving the productivity of food and energy crops.
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Affiliation(s)
| | | | - Philip A. Davey
- School of Biological SciencesUniversity of EssexColchesterUK
| | | | - Tracy Lawson
- School of Biological SciencesUniversity of EssexColchesterUK
| | - Stefan Timm
- Plant Physiology DepartmentUniversity of RostockRostockGermany
| | - Hermann Bauwe
- Plant Physiology DepartmentUniversity of RostockRostockGermany
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South PF, Walker BJ, Cavanagh AP, Rolland V, Badger M, Ort DR. Bile Acid Sodium Symporter BASS6 Can Transport Glycolate and Is Involved in Photorespiratory Metabolism in Arabidopsis thaliana. THE PLANT CELL 2017; 29:808-823. [PMID: 28351992 PMCID: PMC5435425 DOI: 10.1105/tpc.16.00775] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 02/08/2017] [Accepted: 03/28/2017] [Indexed: 05/19/2023]
Abstract
Photorespiration is an energy-intensive process that recycles 2-phosphoglycolate, a toxic product of the Rubisco oxygenation reaction. The photorespiratory pathway is highly compartmentalized, involving the chloroplast, peroxisome, cytosol, and mitochondria. Though the soluble enzymes involved in photorespiration are well characterized, very few membrane transporters involved in photorespiration have been identified to date. In this work, Arabidopsis thaliana plants containing a T-DNA disruption of the bile acid sodium symporter BASS6 show decreased photosynthesis and slower growth under ambient, but not elevated CO2 Exogenous expression of BASS6 complemented this photorespiration mutant phenotype. In addition, metabolite analysis and genetic complementation of glycolate transport in yeast showed that BASS6 was capable of glycolate transport. This is consistent with its involvement in the photorespiratory export of glycolate from Arabidopsis chloroplasts. An Arabidopsis double knockout line of both BASS6 and the glycolate/glycerate transporter PLGG1 (bass6, plgg1) showed an additive growth defect, an increase in glycolate accumulation, and reductions in photosynthetic rates compared with either single mutant. Our data indicate that BASS6 and PLGG1 partner in glycolate export from the chloroplast, whereas PLGG1 alone accounts for the import of glycerate. BASS6 and PLGG1 therefore balance the export of two glycolate molecules with the import of one glycerate molecule during photorespiration.
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Affiliation(s)
- Paul F South
- Global Change and Photosynthesis Research Unit, U.S. Department of Agriculture/Agricultural Research Service, Urbana, Illinois 61801
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, Illinois 61801
| | - Berkley J Walker
- Global Change and Photosynthesis Research Unit, U.S. Department of Agriculture/Agricultural Research Service, Urbana, Illinois 61801
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, Illinois 61801
| | - Amanda P Cavanagh
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, Illinois 61801
| | - Vivien Rolland
- Australian Research Council Centre of Excellence for Translational Photosynthesis, Division of Plant Science, Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra ACT 0200, Australia
| | - Murray Badger
- Australian Research Council Centre of Excellence for Translational Photosynthesis, Division of Plant Science, Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra ACT 0200, Australia
| | - Donald R Ort
- Global Change and Photosynthesis Research Unit, U.S. Department of Agriculture/Agricultural Research Service, Urbana, Illinois 61801
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, Illinois 61801
- Department of Plant Biology, University of Illinois, Urbana, Illinois 61801
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