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Karthick PV, Senthil A, Djanaguiraman M, Anitha K, Kuttimani R, Boominathan P, Karthikeyan R, Raveendran M. Improving Crop Yield through Increasing Carbon Gain and Reducing Carbon Loss. PLANTS (BASEL, SWITZERLAND) 2024; 13:1317. [PMID: 38794389 PMCID: PMC11124956 DOI: 10.3390/plants13101317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/07/2024] [Accepted: 04/10/2024] [Indexed: 05/26/2024]
Abstract
Photosynthesis is a process where solar energy is utilized to convert atmospheric CO2 into carbohydrates, which forms the basis for plant productivity. The increasing demand for food has created a global urge to enhance yield. Earlier, the plant breeding program was targeting the yield and yield-associated traits to enhance the crop yield. However, the yield cannot be further improved without improving the leaf photosynthetic rate. Hence, in this review, various strategies to enhance leaf photosynthesis were presented. The most promising strategies were the optimization of Rubisco carboxylation efficiency, the introduction of a CO2 concentrating mechanism in C3 plants, and the manipulation of photorespiratory bypasses in C3 plants, which are discussed in detail. Improving Rubisco's carboxylation efficiency is possible by engineering targets such as Rubisco subunits, chaperones, and Rubisco activase enzyme activity. Carbon-concentrating mechanisms can be introduced in C3 plants by the adoption of pyrenoid and carboxysomes, which can increase the CO2 concentration around the Rubisco enzyme. Photorespiration is the process by which the fixed carbon is lost through an oxidative process. Different approaches to reduce carbon and nitrogen loss were discussed. Overall, the potential approaches to improve the photosynthetic process and the way forward were discussed in detail.
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Affiliation(s)
- Palanivelu Vikram Karthick
- Department of Crop Physiology, Tamil Nadu Agricultural University, Coimbatore 641003, India; (P.V.K.); (M.D.); (K.A.); (R.K.); (P.B.)
| | - Alagarswamy Senthil
- Department of Crop Physiology, Tamil Nadu Agricultural University, Coimbatore 641003, India; (P.V.K.); (M.D.); (K.A.); (R.K.); (P.B.)
| | - Maduraimuthu Djanaguiraman
- Department of Crop Physiology, Tamil Nadu Agricultural University, Coimbatore 641003, India; (P.V.K.); (M.D.); (K.A.); (R.K.); (P.B.)
| | - Kuppusamy Anitha
- Department of Crop Physiology, Tamil Nadu Agricultural University, Coimbatore 641003, India; (P.V.K.); (M.D.); (K.A.); (R.K.); (P.B.)
| | - Ramalingam Kuttimani
- Department of Crop Physiology, Tamil Nadu Agricultural University, Coimbatore 641003, India; (P.V.K.); (M.D.); (K.A.); (R.K.); (P.B.)
| | - Parasuraman Boominathan
- Department of Crop Physiology, Tamil Nadu Agricultural University, Coimbatore 641003, India; (P.V.K.); (M.D.); (K.A.); (R.K.); (P.B.)
| | - Ramasamy Karthikeyan
- Directorate of Crop Management, Tamil Nadu Agricultural University, Coimbatore 641003, India;
| | - Muthurajan Raveendran
- Directorate of Research, Tamil Nadu Agricultural University, Coimbatore 641003, India;
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2
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Furbank R, Kelly S, von Caemmerer S. Photosynthesis and food security: the evolving story of C 4 rice. PHOTOSYNTHESIS RESEARCH 2023; 158:121-130. [PMID: 37067631 PMCID: PMC10108777 DOI: 10.1007/s11120-023-01014-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 03/15/2023] [Indexed: 06/19/2023]
Abstract
Traditional "Green Revolution" cereal breeding strategies to improve yield are now reaching a plateau in our principal global food crop rice. Photosynthesis has now become a major target of international consortia to increase yield potential. Synthetic biology is being used across multiple large projects to improve photosynthetic efficiency. This review follows the genesis and progress of one of the first of these consortia projects, now in its 13th year; the Bill and Melinda Gates funded C4 Rice Project. This project seeks to install the biochemical and anatomical attributes necessary to support C4 photosynthesis in the C3 crop rice. Here we address the advances made thus far in installing the biochemical pathway and some of the key targets yet to be reached.
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Affiliation(s)
- Robert Furbank
- Division of Plant Science, Centre of Excellence for Translational Photosynthesis, Research School of Biology, Australian National University, Acton, ACT, Australia.
| | - Steven Kelly
- Department of Plant Sciences, University of Oxford, Oxford, UK
| | - Susanne von Caemmerer
- Division of Plant Science, Centre of Excellence for Translational Photosynthesis, Research School of Biology, Australian National University, Acton, ACT, Australia
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3
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Trono D, Pecchioni N. Candidate Genes Associated with Abiotic Stress Response in Plants as Tools to Engineer Tolerance to Drought, Salinity and Extreme Temperatures in Wheat: An Overview. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11233358. [PMID: 36501397 PMCID: PMC9737347 DOI: 10.3390/plants11233358] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/17/2022] [Accepted: 11/30/2022] [Indexed: 05/14/2023]
Abstract
Wheat represents one of the most important staple food crops worldwide and its genetic improvement is fundamental to meeting the global demand of the growing population. However, the environmental stresses, worsened by climate change, and the increasing deterioration of arable land make it very difficult to fulfil this demand. In light of this, the tolerance of wheat to abiotic stresses has become a key objective of genetic improvement, as an effective strategy to ensure high yields without increasing the cultivated land. Genetic erosion related to modern agriculture, whereby elite, high-yielding wheat varieties are the product of high selection pressure, has reduced the overall genetic diversity, including the allelic diversity of genes that could be advantageous for adaptation to adverse environmental conditions. This makes traditional breeding a less effective or slower approach to generating new stress-tolerant wheat varieties. Either mining for the diversity of not-adapted large germplasm pools, or generating new diversity, are the mainstream approaches to be pursued. The advent of genetic engineering has opened the possibility to create new plant variability and its application has provided a strong complement to traditional breeding. Genetic engineering strategies such as transgenesis and genome editing have then provided the opportunity to improve environmental tolerance traits of agronomic importance in cultivated species. As for wheat, several laboratories worldwide have successfully produced transgenic wheat lines with enhanced tolerance to abiotic stresses, and, more recently, significant improvements in the CRISPR/Cas9 tools available for targeted variations within the wheat genome have been achieved. In light of this, the present review aims to provide successful examples of genetic engineering applications for the improvement of wheat adaptation to drought, salinity and extreme temperatures, which represent the most frequent and most severe events causing the greatest losses in wheat production worldwide.
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Chatterjee J, Coe RA, Acebron K, Thakur V, Yennamalli RM, Danila F, Lin HC, Balahadia CP, Bagunu E, Padhma PPOS, Bala S, Yin X, Rizal G, Dionora J, Furbank RT, von Caemmerer S, Quick WP. A low CO2-responsive mutant of Setaria viridis reveals that reduced carbonic anhydrase limits C4 photosynthesis. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:3122-3136. [PMID: 33528493 PMCID: PMC8023212 DOI: 10.1093/jxb/erab039] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 01/30/2021] [Indexed: 06/12/2023]
Abstract
In C4 species, β-carbonic anhydrase (CA), localized to the cytosol of the mesophyll cells, accelerates the interconversion of CO2 to HCO3-, the substrate used by phosphoenolpyruvate carboxylase (PEPC) in the first step of C4 photosynthesis. Here we describe the identification and characterization of low CO2-responsive mutant 1 (lcr1) isolated from an N-nitroso-N-methylurea- (NMU) treated Setaria viridis mutant population. Forward genetic investigation revealed that the mutated gene Sevir.5G247800 of lcr1 possessed a single nucleotide transition from cytosine to thymine in a β-CA gene causing an amino acid change from leucine to phenylalanine. This resulted in severe reduction in growth and photosynthesis in the mutant. Both the CO2 compensation point and carbon isotope discrimination values of the mutant were significantly increased. Growth of the mutants was stunted when grown under ambient pCO2 but recovered at elevated pCO2. Further bioinformatics analyses revealed that the mutation has led to functional changes in one of the conserved residues of the protein, situated near the catalytic site. CA transcript accumulation in the mutant was 80% lower, CA protein accumulation 30% lower, and CA activity ~98% lower compared with the wild type. Changes in the abundance of other primary C4 pathway enzymes were observed; accumulation of PEPC protein was significantly increased and accumulation of malate dehydrogenase and malic enzyme decreased. The reduction of CA protein activity and abundance in lcr1 restricts the supply of bicarbonate to PEPC, limiting C4 photosynthesis and growth. This study establishes Sevir.5G247800 as the major CA allele in Setaria for C4 photosynthesis and provides important insights into the function of CA in C4 photosynthesis that would be required to generate a rice plant with a functional C4 biochemical pathway.
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Affiliation(s)
- Jolly Chatterjee
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - Robert A Coe
- CSIRO Agriculture Flagship, Australian Plant Phenomics Facility, GPO Box 1500, Canberra, ACT 2601, Australia
| | - Kelvin Acebron
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - Vivek Thakur
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
- Department of Systems & Computational Biology, School of Life Sciences, University of Hyderabad, Hyderabad-500046, India
| | - Ragothaman M Yennamalli
- Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, Tamilnadu-613401, India
| | - Florence Danila
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, Australian National University, GPO Box 1500, Canberra, ACT 2601, Australia
| | - Hsiang-Chun Lin
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
| | | | - Efren Bagunu
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - Preiya P O S Padhma
- Department of Systems & Computational Biology, School of Life Sciences, University of Hyderabad, Hyderabad-500046, India
| | - Soumi Bala
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, Australian National University, GPO Box 1500, Canberra, ACT 2601, Australia
| | - Xiaojia Yin
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - Govinda Rizal
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - Jacqueline Dionora
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - Robert T Furbank
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, Australian National University, GPO Box 1500, Canberra, ACT 2601, Australia
| | - Susanne von Caemmerer
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, Australian National University, GPO Box 1500, Canberra, ACT 2601, Australia
| | - William Paul Quick
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
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Iannella L, Botrè F, Colamonici C, Curcio D, Ciccarelli C, Mazzarino M, Torre X. Carbon isotopic characterization of prednisolone and prednisone pharmaceutical formulations: Implications in antidoping analysis. Drug Test Anal 2020; 12:1587-1598. [DOI: 10.1002/dta.2876] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 06/03/2020] [Accepted: 06/05/2020] [Indexed: 01/21/2023]
Affiliation(s)
- Loredana Iannella
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana Rome Italy
- Dipartimento di Chimica e Tecnologia del Farmaco “Sapienza” Università di Roma Rome Italy
| | - Francesco Botrè
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana Rome Italy
- Dipartimento di Medicina Sperimentale “Sapienza” Università di Roma Rome Italy
| | | | - Davide Curcio
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana Rome Italy
| | | | - Monica Mazzarino
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana Rome Italy
| | - Xavier Torre
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana Rome Italy
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Kohli A, Miro B, Balié J, d’A Hughes J. Photosynthesis research: a model to bridge fundamental science, translational products, and socio-economic considerations in agriculture. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:2281-2298. [PMID: 32076700 PMCID: PMC7135011 DOI: 10.1093/jxb/eraa087] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Accepted: 02/19/2020] [Indexed: 05/04/2023]
Abstract
Despite impressive success in molecular physiological understanding of photosynthesis, and preliminary evidence on its potential for quantum shifts in agricultural productivity, the question remains of whether increased photosynthesis, without parallel fine-tuning of the associated processes, is enough. There is a distinct lack of formal socio-economic impact studies that address the critical questions of product profiling, cost-benefit analysis, environmental trade-offs, and technological and market forces in product acceptability. When a relatively well understood process gains enough traction for translational value, its broader scientific and technical gap assessment, in conjunction with its socio-economic impact assessment for success, should be a prerequisite. The successes in the upstream basic understanding of photosynthesis should be integrated with a gap analysis for downstream translational applications to impact the farmers' and customers' lifestyles and livelihoods. The purpose of this review is to assess how the laboratory, the field, and the societal demands from photosynthesis could generate a transformative product. Two crucial recommendations from the analysis of the state of knowledge and potential ways forward are (i) the formulation of integrative mega-projects, which span the multistakeholder spectrum, to ensure rapid success in harnessing the transformative power of photosynthesis; and (ii) stipulating spatiotemporal, labour, and economic criteria to stage-gate deliverables.
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Affiliation(s)
- Ajay Kohli
- International Rice Research Institute, Los Baños, Philippines
| | - Berta Miro
- International Rice Research Institute, Los Baños, Philippines
| | - Jean Balié
- International Rice Research Institute, Los Baños, Philippines
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7
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Yadav S, Mishra A. Ectopic expression of C 4 photosynthetic pathway genes improves carbon assimilation and alleviate stress tolerance for future climate change. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2020; 26:195-209. [PMID: 32153323 PMCID: PMC7036372 DOI: 10.1007/s12298-019-00751-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Revised: 12/10/2019] [Accepted: 12/23/2019] [Indexed: 05/04/2023]
Abstract
Alteration in atmospheric carbon dioxide concentration and other environmental factors are the significant cues of global climate change. Environmental factors affect the most fundamental biological process including photosynthesis and different metabolic pathways. The feeding of the rapidly growing world population is another challenge which imposes pressure to improve productivity and quality of the existing crops. C4 plants are considered the most productive, containing lower photorespiration, and higher water-use & N-assimilation efficiencies, compared to C3 plants. Besides, the C4-photosynthetic genes not only play an important role in carbon assimilation but also modulate abiotic stresses. In this review, fundamental three metabolic processes (C4, C3, and CAM) of carbon dioxide assimilation, the evolution of C4-photosynthetic genes, effect of elevated CO2 on photosynthesis, and overexpression of C4-photosynthetic genes for higher photosynthesis were discussed. Kranz-anatomy is considered an essential prerequisite for the terrestrial C4 carbon assimilation, but single-celled C4 plant species changed this well-established paradigm. C4 plants are insensitive to an elevated CO2 stress condition but performed better under stress conditions. Overexpression of essential C4-photosynthetic genes such as PEPC, PPDK, and NADP-ME in C3 plants like Arabidopsis, tobacco, rice, wheat, and potato not only improved photosynthesis but also provided tolerance to various environmental stresses, especially drought. The review provides useful information for sustainable productivity and yield under elevated CO2 environment, which to be explored further for CO2 assimilation and also abiotic stress tolerance. Additionally, it provides a better understanding to explore C4-photosynthetic gene(s) to cope with global warming and prospective adverse climatic changes.
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Affiliation(s)
- Sonam Yadav
- Division of Applied Phycology and Biotechnology, CSIR-Central Salt and Marine Chemicals Research Institute, G. B. Marg, Bhavnagar, Gujarat India
| | - Avinash Mishra
- Division of Applied Phycology and Biotechnology, CSIR-Central Salt and Marine Chemicals Research Institute, G. B. Marg, Bhavnagar, Gujarat India
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Ermakova M, Danila FR, Furbank RT, von Caemmerer S. On the road to C 4 rice: advances and perspectives. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:940-950. [PMID: 31596523 PMCID: PMC7065233 DOI: 10.1111/tpj.14562] [Citation(s) in RCA: 98] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 09/27/2019] [Accepted: 10/03/2019] [Indexed: 05/18/2023]
Abstract
The international C4 rice consortium aims to introduce into rice a high capacity photosynthetic mechanism, the C4 pathway, to increase yield. The C4 pathway is characterised by a complex combination of biochemical and anatomical specialisation that ensures high CO2 partial pressure at RuBisCO sites in bundle sheath (BS) cells. Here we report an update of the progress of the C4 rice project. Since its inception in 2008 there has been an exponential growth in synthetic biology and molecular tools. Golden Gate cloning and synthetic promoter systems have facilitated gene building block approaches allowing multiple enzymes and metabolite transporters to be assembled and expressed from single gene constructs. Photosynthetic functionalisation of the BS in rice remains an important step and there has been some success overexpressing transcription factors in the cytokinin signalling network which influence chloroplast volume. The C4 rice project has rejuvenated the research interest in C4 photosynthesis. Comparative anatomical studies now point to critical features essential for the design. So far little attention has been paid to the energetics. C4 photosynthesis has a greater ATP requirement, which is met by increased cyclic electron transport in BS cells. We hypothesise that changes in energy statues may drive this increased capacity for cyclic electron flow without the need for further modification. Although increasing vein density will ultimately be necessary for high efficiency C4 rice, our modelling shows that small amounts of C4 photosynthesis introduced around existing veins could already provide benefits of increased photosynthesis on the road to C4 rice.
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Affiliation(s)
- Maria Ermakova
- Australian Research Council Centre of Excellence for Translational PhotosynthesisDivision of Plant ScienceResearch School of BiologyThe Australian National UniversityActonACT2601Australia
| | - Florence R. Danila
- Australian Research Council Centre of Excellence for Translational PhotosynthesisDivision of Plant ScienceResearch School of BiologyThe Australian National UniversityActonACT2601Australia
| | - Robert T. Furbank
- Australian Research Council Centre of Excellence for Translational PhotosynthesisDivision of Plant ScienceResearch School of BiologyThe Australian National UniversityActonACT2601Australia
| | - Susanne von Caemmerer
- Australian Research Council Centre of Excellence for Translational PhotosynthesisDivision of Plant ScienceResearch School of BiologyThe Australian National UniversityActonACT2601Australia
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9
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Lin H, Arrivault S, Coe RA, Karki S, Covshoff S, Bagunu E, Lunn JE, Stitt M, Furbank RT, Hibberd JM, Quick WP. A Partial C 4 Photosynthetic Biochemical Pathway in Rice. FRONTIERS IN PLANT SCIENCE 2020; 11:564463. [PMID: 33178234 PMCID: PMC7593541 DOI: 10.3389/fpls.2020.564463] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 09/25/2020] [Indexed: 05/21/2023]
Abstract
Introduction of a C4 photosynthetic pathway into C3 rice (Oryza sativa) requires installation of a biochemical pump that concentrates CO2 at the site of carboxylation in modified bundle sheath cells. To investigate the feasibility of this, we generated a quadruple line that simultaneously accumulates four of the core C4 photosynthetic enzymes from the NADP-malic enzyme subtype, phosphoenolpyruvate carboxylase (ZmPEPC), NADP-malate dehydrogenase (ZmNADP-MDH), NADP-malic enzyme (ZmNADP-ME), and pyruvate phosphate dikinase (ZmPPDK). This led to enhanced enzyme activity and mild phenotypic perturbations but was largely neutral in its effects on photosynthetic rate. Measurements of the flux of 13CO2 through photosynthetic metabolism revealed a significant increase in the incorporation of 13C into malate, consistent with increased fixation of 13CO2 via PEP carboxylase in lines expressing the maize PEPC enzyme. However, there was no significant differences in labeling of 3-phosphoglycerate (3PGA) indicating that there was no carbon flux through NADP-ME into the Calvin-Benson cycle. There was also no significant difference in labeling of phosphoenolpyruvate (PEP) indicating that there was no carbon flux through PPDK. Crossing the quadruple line with a line with reduced glycine decarboxylase H-protein (OsGDCH) abundance led to a photosynthetic phenotype characteristic of the reduced OsGDCH line and higher labeling of malate, aspartate and citrate than in the quintuple line. There was evidence of 13C labeling of aspartate indicating 13CO2 fixation into oxaloacetate by PEPC and conversion to aspartate by the endogenous aspartate aminotransferase activity. While Kranz anatomy or other anatomical modifications have not yet been installed in these plants to enable a fully functional C4 cycle, these results demonstrate for the first-time a partial flux through the carboxylation phase of NADP-ME C4 metabolism in transgenic rice containing two of the key metabolic steps in the C4 pathway.
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Affiliation(s)
- HsiangChun Lin
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - Stéphanie Arrivault
- Max Planck Institute of Molecular Plant Physiology (MPI-MP), Potsdam, Germany
| | - Robert A. Coe
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - Shanta Karki
- National Centre for Fruit Development, Kirtipur, Nepal
| | - Sarah Covshoff
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Efren Bagunu
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - John E. Lunn
- Max Planck Institute of Molecular Plant Physiology (MPI-MP), Potsdam, Germany
| | - Mark Stitt
- Max Planck Institute of Molecular Plant Physiology (MPI-MP), Potsdam, Germany
| | - Robert T. Furbank
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, The Australian National University, Acton, ACT, Australia
| | - Julian M. Hibberd
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - William Paul Quick
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, United Kingdom
- *Correspondence: William Paul Quick,
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Giuliani R, Karki S, Covshoff S, Lin HC, Coe RA, Koteyeva NK, Evans MA, Quick WP, von Caemmerer S, Furbank RT, Hibberd JM, Edwards GE, Cousins AB. Transgenic maize phosphoenolpyruvate carboxylase alters leaf-atmosphere CO 2 and 13CO 2 exchanges in Oryza sativa. PHOTOSYNTHESIS RESEARCH 2019; 142:153-167. [PMID: 31325077 PMCID: PMC6848035 DOI: 10.1007/s11120-019-00655-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 06/11/2019] [Indexed: 05/07/2023]
Abstract
The engineering process of C4 photosynthesis into C3 plants requires an increased activity of phosphoenolpyruvate carboxylase (PEPC) in the cytosol of leaf mesophyll cells. The literature varies on the physiological effect of transgenic maize (Zea mays) PEPC (ZmPEPC) leaf expression in Oryza sativa (rice). Therefore, to address this issue, leaf-atmosphere CO2 and 13CO2 exchanges were measured, both in the light (at atmospheric O2 partial pressure of 1.84 kPa and at different CO2 levels) and in the dark, in transgenic rice expressing ZmPEPC and wild-type (WT) plants. The in vitro PEPC activity was 25 times higher in the PEPC overexpressing (PEPC-OE) plants (~20% of maize) compared to the negligible activity in WT. In the PEPC-OE plants, the estimated fraction of carboxylation by PEPC (β) was ~6% and leaf net biochemical discrimination against 13CO2[Formula: see text] was ~ 2‰ lower than in WT. However, there were no differences in leaf net CO2 assimilation rates (A) between genotypes, while the leaf dark respiration rates (Rd) over three hours after light-dark transition were enhanced (~ 30%) and with a higher 13C composition [Formula: see text] in the PEPC-OE plants compared to WT. These data indicate that ZmPEPC in the PEPC-OE rice plants contributes to leaf carbon metabolism in both the light and in the dark. However, there are some factors, potentially posttranslational regulation and PEP availability, which reduce ZmPEPC activity in vivo.
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Affiliation(s)
- Rita Giuliani
- School of Biological Sciences, Molecular Plant Sciences, Washington State University, Pullman, WA, 99164-4236, USA
| | - Shanta Karki
- C4 Rice Center, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - Sarah Covshoff
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK
| | - Hsiang-Chun Lin
- C4 Rice Center, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - Robert A Coe
- C4 Rice Center, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - Nuria K Koteyeva
- Laboratory of Anatomy and Morphology, V.L. Komarov Botanical Institute of the Russian Academy of Sciences, Prof. Popov Street 2, St. Petersburg, Russia, 197376
| | - Marc A Evans
- Department of Mathematics and Statistics, Washington State University, Pullman, WA, 99164-3113, USA
| | - W Paul Quick
- C4 Rice Center, International Rice Research Institute (IRRI), Los Baños, Philippines
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - Susanne von Caemmerer
- Division of Plant Sciences, Research School of Biology, The Australian National University, Canberra, ACT, 0200, Australia
| | - Robert T Furbank
- Division of Plant Sciences, Research School of Biology, The Australian National University, Canberra, ACT, 0200, Australia
| | - Julian M Hibberd
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK
| | - Gerald E Edwards
- School of Biological Sciences, Molecular Plant Sciences, Washington State University, Pullman, WA, 99164-4236, USA
| | - Asaph B Cousins
- School of Biological Sciences, Molecular Plant Sciences, Washington State University, Pullman, WA, 99164-4236, USA.
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11
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Philipp D, Putman B, Thoma G. ASAS-CSAS ANNUAL MEETING SYMPOSIUM ON WATER USE EFFICIENCY AT THE FORAGE-ANIMAL INTERFACE: Life cycle assessment of forage-based livestock production systems. J Anim Sci 2019; 97:1865-1873. [PMID: 30689888 DOI: 10.1093/jas/skz035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 01/18/2019] [Indexed: 11/12/2022] Open
Abstract
Livestock production is increasingly subjected to environmental and economic challenges related to water quantities being utilized, expressed as green (evapotranspiration from rainwater), blue (surface and groundwater), or gray (waste) water footprints at each stage of the product life cycle. Published data indicated that the largest share of water being used for producing beef in the United States can be traced back to growing forage and feed (>90%), whereby the green water footprint was substantially greater (12,933 liters of water per kg of product) than the blue water footprint, as only a small amount of pasture- and cropland is irrigated (525 L/kg). Based on prevailing quantification methods, feed conversion ratios, and grazing land required, water footprints for beef produced through grazing alone can be relatively high. Green water footprints can easily reach more than 19,000 L/kg for beef from grazing compared with a maximum of 1,731 L/kg for chicken under a typical scenario. However, much of the existing grazing land cannot or should not be converted to cropland for various ecological reasons, and large water footprints would remain for the vegetation even if cattle were removed. Life cycle assessments (LCA) were historically developed to provide a framework for evaluation of the full life cycle of a product or service and to ultimately model environmental impacts through life cycle impact assessment methods. Life cycle assessments grew more refined during past years and efforts are being made to reflect the environmental and economic consequences of different livestock and crop production systems more accurately than in the past. Typical beef production systems on natural and naturalized grasslands in North America generate environmental, economic, and societal benefits that should be reflected in future LCA, farm policies, and regulations. To increase the water use efficiency of each segment of the beef supply chain and thereby to reduce water footprints, grazing systems and methods as well as external inputs should be further optimized and integrated toward enhanced ecosystem services, thereby lowering the overall environmental impact of livestock production.
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Affiliation(s)
- Dirk Philipp
- Division of Agriculture, University of Arkansas, Fayetteville, AR
| | - Ben Putman
- Department of Chemical Engineering, University of Arkansas, Fayetteville, AR
| | - Greg Thoma
- Department of Chemical Engineering, University of Arkansas, Fayetteville, AR
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Hsu SY, Smanski MJ. Designing and Implementing Algorithmic DNA Assembly Pipelines for Multi-Gene Systems. Methods Mol Biol 2018; 1671:131-147. [PMID: 29170957 DOI: 10.1007/978-1-4939-7295-1_9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Advances in DNA synthesis and assembly technology allow for the high-throughput fabrication of hundreds to thousands of multi-part genetic constructs in a short time. This allows for rapid hypothesis-testing and genetic optimization in multi-gene biological systems. Here, we discuss key considerations to design and implement an algorithmic DNA assembly pipeline that provides the freedom to change nearly any design variable in a multi-gene system. In addition to considerations for pipeline design, we describe protocols for three useful molecular biology techniques in plasmid construction.
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Affiliation(s)
- Szu-Yi Hsu
- Department of Biochemistry, Molecular Biology, and Biophysics and BioTechnology Institute, University of Minnesota, Twin Cities, Saint Paul, MN, 55108, USA
| | - Michael J Smanski
- Department of Biochemistry, Molecular Biology, and Biophysics and BioTechnology Institute, University of Minnesota, Twin Cities, Saint Paul, MN, 55108, USA.
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van Tol N, Rolloos M, Augustijn D, Alia A, de Groot HJ, Hooykaas PJJ, van der Zaal BJ. An Arabidopsis mutant with high operating efficiency of Photosystem II and low chlorophyll fluorescence. Sci Rep 2017; 7:3314. [PMID: 28607440 PMCID: PMC5468348 DOI: 10.1038/s41598-017-03611-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 05/03/2017] [Indexed: 11/09/2022] Open
Abstract
The overall light energy to biomass conversion efficiency of plant photosynthesis is generally regarded as low. Forward genetic screens in Arabidopsis have yielded very few mutants with substantially enhanced photochemistry. Here, we report the isolation of a novel Arabidopsis mutant with a high operating efficiency of Photosystem II (φPSII) and low chlorophyll fluorescence from a library of lines harboring T-DNA constructs encoding artificial transcription factors. This mutant was named Low Chlorophyll Fluorescence 1 (LCF1). Only a single T-DNA insertion was detected in LCF1, which interrupted the expression of the full length mRNA of the gene At4g36280 (MORC2). We demonstrate that the high φPSII and low levels of chlorophyll fluorescence were due to a decrease in PSII:PSI ratio. Although LCF1 plants had decreased rosette surface area and biomass under normal growth conditions, they contained more starch per gram fresh weight. The growth defect of LCF1 was alleviated by low light and short day conditions, and growth could even be enhanced after a period of dark-induced senescence, showing that the plant can utilize its excess photosynthetic conversion capacity as a resource when needed.
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Affiliation(s)
- Niels van Tol
- Institute of Biology Leiden, Faculty of Science, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
- BioSolar Cells, P.O. Box 98, 6700 AB, Wageningen, The Netherlands
| | - Martijn Rolloos
- Institute of Biology Leiden, Faculty of Science, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Dieuwertje Augustijn
- Leiden Institute of Chemistry, Faculty of Science, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - A Alia
- Leiden Institute of Chemistry, Faculty of Science, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - Huub J de Groot
- Leiden Institute of Chemistry, Faculty of Science, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - Paul J J Hooykaas
- Institute of Biology Leiden, Faculty of Science, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Bert J van der Zaal
- Institute of Biology Leiden, Faculty of Science, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands.
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Qin N, Xu W, Hu L, Li Y, Wang H, Qi X, Fang Y, Hua X. Drought tolerance and proteomics studies of transgenic wheat containing the maize C 4 phosphoenolpyruvate carboxylase (PEPC) gene. PROTOPLASMA 2016; 253:1503-1512. [PMID: 26560113 DOI: 10.1007/s00709-015-0906-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 10/29/2015] [Indexed: 05/12/2023]
Abstract
Enhancing drought tolerance of crops has been a great challenge in crop improvement. Here, we report the maize phosphoenolpyruvate carboxylase (PEPC) gene was able to confer drought tolerance and increase grain yield in transgenic wheat (Triticum aestivum L.) plants. The improved of drought tolerance was associated with higher levels of proline, soluble sugar, soluble protein, and higher water use efficiency. The transgenic wheat plants had also a more extensive root system as well as increased photosynthetic capacity during stress treatments. The increased grain yield of the transgenic wheat was contributed by improved biomass, larger spike and grain numbers, and heavier 1000-grain weight under drought-stress conditions. Under non-stressed conditions, there were no significant increases in these of the measured traits except for photosynthetic rate when compared with parental wheat. Proteomic research showed that the expression levels of some proteins, including chlorophyll A-B binding protein and pyruvate, phosphate dikinase, which are related to photosynthesis, PAP fibrillin, which is involved in cytoskeleton synthesis, S-adenosylmethionine synthetase, which catalyzes methionine synthesis, were induced in the transgenic wheat under drought stress. Additionally, the expression of glutamine synthetase, which is involved in ammonia assimilation, was induced by drought stress in the wheat. Our study shows that PEPC can improve both stress tolerance and grain yield in wheat, demonstrating the efficacy of PEPC in crop improvement.
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Affiliation(s)
- Na Qin
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, 210095, Nanjing, Jiangsu, China
| | - Weigang Xu
- Wheat Research Institute, Henan Academy of Agricultural Sciences, 450002, Zhengzhou, Henan, China.
| | - Lin Hu
- Wheat Research Institute, Henan Academy of Agricultural Sciences, 450002, Zhengzhou, Henan, China
| | - Yan Li
- Wheat Research Institute, Henan Academy of Agricultural Sciences, 450002, Zhengzhou, Henan, China
| | - Huiwei Wang
- Wheat Research Institute, Henan Academy of Agricultural Sciences, 450002, Zhengzhou, Henan, China
| | - Xueli Qi
- Wheat Research Institute, Henan Academy of Agricultural Sciences, 450002, Zhengzhou, Henan, China
| | - Yuhui Fang
- Wheat Research Institute, Henan Academy of Agricultural Sciences, 450002, Zhengzhou, Henan, China
| | - Xia Hua
- Wheat Research Institute, Henan Academy of Agricultural Sciences, 450002, Zhengzhou, Henan, China
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Kanwal P, Gupta S, Arora S, Kumar A. Identification of genes involved in carbon metabolism from Eleusine coracana (L.) for understanding their light-mediated entrainment and regulation. PLANT CELL REPORTS 2014; 33:1403-11. [PMID: 24825394 DOI: 10.1007/s00299-014-1625-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 04/12/2014] [Accepted: 04/17/2014] [Indexed: 05/22/2023]
Abstract
The study would be helpful in understanding the synchronization of genes of a pathway and its effect on carbon metabolism which can be further utilized for better agronomic performance. Finger millet (Eleusine coracana) is a C4 crop with high nitrogen use efficiency (NUE) said to be organic by default. Being carbon and nitrogen mutually exclusive, in the present study, it was investigated how light regulates the expression of genes of carbon metabolism and photosynthesis in two finger millet genotypes (GE 3885 and GE 1437) with differing grain protein content (13.8 and 6.2%). Different genes associated with carbon metabolism were isolated (Cab, RBCS, PEPC, PPDK, PEPC-k, ME, SPS, PK, 14-3-3 and SnRK1) and the co-expression of Dof1 and these genes was investigated under different light-dark conditions. The deduced protein sequences of isolated genes showed relationship of marked variations with their homolog which might corresponds to difference in photosynthetic efficiency between finger millet and other plants. In 24 h day-night conditions, the identified genes exhibited diurnal rhythm in both genotypes with different time of peak expression. In dark, the expression of identified genes in both genotypes oscillated with varied amplitude indicating their control by an endogenous clock. However, Cab, RBCS and PPDK showed no oscillations suggesting that genes are light inducible. Exceptionally, ME transcript showed differential response within genotypes. Upon illumination, genes were induced within the measured period indicating that light is a signal involved in the entrainment of these genes. Exception was ME and SnRK1 in GE 1437. We conclude that expression of Dof1 in higher grain protein genotype was more consistent with the expression of carbon metabolism genes under study suggesting that Dof1 differentially regulates the expression of these light inducible genes and simultaneously controls the grain protein content in finger millet genotypes.
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Affiliation(s)
- Pooja Kanwal
- Department of Molecular Biology and Genetic Engineering, College of Basic Sciences and Humanities, GB Pant University of Agriculture and Technology, Pantnagar, 263145, Uttarakhand, India
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Gu JF, Qiu M, Yang JC. Enhanced tolerance to drought in transgenic rice plants overexpressing C4 photosynthesis enzymes. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.cj.2013.10.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Slewinski TL. Diverse functional roles of monosaccharide transporters and their homologs in vascular plants: a physiological perspective. MOLECULAR PLANT 2011; 4:641-62. [PMID: 21746702 DOI: 10.1093/mp/ssr051] [Citation(s) in RCA: 133] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Vascular plants contain two gene families that encode monosaccharide transporter proteins. The classical monosaccharide transporter(-like) gene superfamily is large and functionally diverse, while the recently identified SWEET transporter family is smaller and, thus far, only found to transport glucose. These transporters play essential roles at many levels, ranging from organelles to the whole plant. Many family members are essential for cellular homeostasis and reproductive success. Although most transporters do not directly participate in long-distance transport, their indirect roles greatly impact carbon allocation and transport flux to the heterotrophic tissues of the plant. Functional characterization of some members from both gene families has revealed their diverse roles in carbohydrate partitioning, phloem function, resource allocation, plant defense, and sugar signaling. This review highlights the broad impacts and implications of monosaccharide transport by describing some of the functional roles of the monosaccharide transporter(-like) superfamily and the SWEET transporter family.
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Affiliation(s)
- Thomas L Slewinski
- Department of Plant Biology, Cornell University, 262 Plant Science Building, Ithaca, NY 14853, USA.
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Ruan CJ, Shao HB, Teixeira da Silva JA. A critical review on the improvement of photosynthetic carbon assimilation in C3 plants using genetic engineering. Crit Rev Biotechnol 2011; 32:1-21. [PMID: 21699437 DOI: 10.3109/07388551.2010.533119] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Global warming is one of the most serious challenges facing us today. It may be linked to the increase in atmospheric CO2 and other greenhouse gases (GHGs), leading to a rise in sea level, notable shifts in ecosystems, and in the frequency and intensity of wild fires. There is a strong interest in stabilizing the atmospheric concentration of CO2 and other GHGs by decreasing carbon emission and/or increasing carbon sequestration. Biotic sequestration is an important and effective strategy to mitigate the effects of rising atmospheric CO2 concentrations by increasing carbon sequestration and storage capacity of ecosystems using plant photosynthesis and by decreasing carbon emission using biofuel rather than fossil fuel. Improvement of photosynthetic carbon assimilation, using transgenic engineering, potentially provides a set of available and effective tools for enhancing plant carbon sequestration. In this review, firstly different biological methods of CO2 assimilation in C3, C4 and CAM plants are introduced and three types of C4 pathways which have high photosynthetic performance and have evolved as CO2 pumps are briefly summarized. Then (i) the improvement of photosynthetic carbon assimilation of C3 plants by transgenic engineering using non-C4 genes, and (ii) the overexpression of individual or multiple C4 cycle photosynthetic genes (PEPC, PPDK, PCK, NADP-ME and NADP-MDH) in transgenic C3 plants (e.g. tobacco, potato, rice and Arabidopsis) are highlighted. Some transgenic C3 plants (e.g. tobacco, rice and Arabidopsis) overexpressing the FBP/SBPase, ictB and cytochrome c6 genes showed positive effects on photosynthetic efficiency and growth characteristics. However, over the last 28 years, efforts to overexpress individual, double or multiple C4 enzymes in C3 plants like tobacco, potato, rice, and Arabidopsis have produced mixed results that do not confirm or eliminate the possibility of improving photosynthesis of C3 plants by this approach. Finally, a prospect is provided on the challenges of enhancing carbon assimilation of C3 plants using transgenic engineering in the face of global warming, and the trends of the most promising approaches to improving the photosynthetic performance of C3 plants.
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Affiliation(s)
- Cheng-Jiang Ruan
- Key Laboratory of Biotechnology & Bio-Resources Utilization, Dalian Nationalities University, Dalian City, Liaoning, China.
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Miyao M, Masumoto C, Miyazawa SI, Fukayama H. Lessons from engineering a single-cell C(4) photosynthetic pathway into rice. JOURNAL OF EXPERIMENTAL BOTANY 2011; 62:3021-9. [PMID: 21459764 DOI: 10.1093/jxb/err023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The transfer of C(4) plant traits into C(3) plants has long been a strategy for improving the photosynthetic performance of C(3) plants. The introduction of a pathway mimicking the C(4) photosynthetic pathway into the mesophyll cells of C(3) plants was only a realistic approach when transgenic technology was sufficiently well developed and widely adopted. Here an attempt to introduce a single-cell C(4)-like pathway in which CO(2) capture and release occur in the mesophyll cell, such as the one found in the aquatic plant Hydrilla verticillata (L.f.) Royle, into rice (Oryza sativa L.) is described. Four enzymes involved in this pathway were successfully overproduced in the transgenic rice leaves, and 12 different sets of transgenic rice that overproduce these enzymes independently or in combination were produced and analysed. Although none of these transformants has yet shown dramatic improvements in photosynthesis, these studies nonetheless have important implications for the evolution of C(4) photosynthetic genes and their metabolic regulation, and have shed light on the unique aspects of rice physiology and metabolism. This article summarizes the lessons learned during these attempts to engineer single-cell C(4) rice.
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Affiliation(s)
- Mitsue Miyao
- Photobiology and Photosynthesis Research Unit, National Institute of Agrobiological Sciences, Kannondai, Tsukuba 305-8602, Japan.
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Kajala K, Covshoff S, Karki S, Woodfield H, Tolley BJ, Dionora MJA, Mogul RT, Mabilangan AE, Danila FR, Hibberd JM, Quick WP. Strategies for engineering a two-celled C(4) photosynthetic pathway into rice. JOURNAL OF EXPERIMENTAL BOTANY 2011; 62:3001-10. [PMID: 21335436 DOI: 10.1093/jxb/err022] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Every day almost one billion people suffer from chronic hunger, and the situation is expected to deteriorate with a projected population growth to 9 billion worldwide by 2050. In order to provide adequate nutrition into the future, rice yields in Asia need to increase by 60%, a change that may be achieved by introduction of the C(4) photosynthetic cycle into rice. The international C(4) Rice Consortium was founded in order to test the feasibility of installing the C(4) engine into rice. This review provides an update on two of the many approaches employed by the C(4) Rice Consortium: namely, metabolic C(4) engineering and identification of determinants of leaf anatomy by mutant screens. The aim of the metabolic C(4) engineering approach is to generate a two-celled C(4) shuttle in rice by expressing the classical enzymes of the NADP-ME C(4) cycle in a cell-appropriate manner. The aim is also to restrict RuBisCO and glycine decarboxylase expression to the bundle sheath (BS) cells of rice in a C(4)-like fashion by specifically down-regulating their expression in rice mesophyll (M) cells. In addition to the changes in biochemistry, two-celled C(4) species show a convergence in leaf anatomy that include increased vein density and reduced numbers of M cells between veins. By screening rice activation-tagged lines and loss-of-function sorghum mutants we endeavour to identify genes controlling these key traits.
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Affiliation(s)
- Kaisa Kajala
- Department of Plant Sciences, University of Cambridge, Downing Site, Cambridge CB2 3EA, Cambridge, UK
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Microbial lipids from renewable resources: production and characterization. J Ind Microbiol Biotechnol 2010; 37:1271-87. [DOI: 10.1007/s10295-010-0884-5] [Citation(s) in RCA: 211] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Accepted: 09/18/2010] [Indexed: 11/30/2022]
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Wang X, Gowik U, Tang H, Bowers JE, Westhoff P, Paterson AH. Comparative genomic analysis of C4 photosynthetic pathway evolution in grasses. Genome Biol 2009; 10:R68. [PMID: 19549309 PMCID: PMC2718502 DOI: 10.1186/gb-2009-10-6-r68] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2009] [Revised: 05/27/2009] [Accepted: 06/23/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Sorghum is the first C4 plant and the second grass with a full genome sequence available. This makes it possible to perform a whole-genome-level exploration of C4 pathway evolution by comparing key photosynthetic enzyme genes in sorghum, maize (C4) and rice (C3), and to investigate a long-standing hypothesis that a reservoir of duplicated genes is a prerequisite for the evolution of C4 photosynthesis from a C3 progenitor. RESULTS We show that both whole-genome and individual gene duplication have contributed to the evolution of C4 photosynthesis. The C4 gene isoforms show differential duplicability, with some C4 genes being recruited from whole genome duplication duplicates by multiple modes of functional innovation. The sorghum and maize carbonic anhydrase genes display a novel mode of new gene formation, with recursive tandem duplication and gene fusion accompanied by adaptive evolution to produce C4 genes with one to three functional units. Other C4 enzymes in sorghum and maize also show evidence of adaptive evolution, though differing in level and mode. Intriguingly, a phosphoenolpyruvate carboxylase gene in the C3 plant rice has also been evolving rapidly and shows evidence of adaptive evolution, although lacking key mutations that are characteristic of C4 metabolism. We also found evidence that both gene redundancy and alternative splicing may have sheltered the evolution of new function. CONCLUSIONS Gene duplication followed by functional innovation is common to evolution of most but not all C4 genes. The apparently long time-lag between the availability of duplicates for recruitment into C4 and the appearance of C4 grasses, together with the heterogeneity of origins of C4 genes, suggests that there may have been a long transition process before the establishment of C4 photosynthesis.
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Affiliation(s)
- Xiyin Wang
- Plant Genome Mapping Laboratory, University of Georgia, Athens, GA 30602, USA
- College of Sciences, Hebei Polytechnic University, Tangshan, Hebei 063000, China
| | - Udo Gowik
- Institut fur Entwicklungs- und Molekularbiologie der Pflanzen, Heinrich-Heine-Universitat 1, Universitatsstrasse, D-40225 Dusseldorf, Germany
| | - Haibao Tang
- Plant Genome Mapping Laboratory, University of Georgia, Athens, GA 30602, USA
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - John E Bowers
- Plant Genome Mapping Laboratory, University of Georgia, Athens, GA 30602, USA
| | - Peter Westhoff
- Institut fur Entwicklungs- und Molekularbiologie der Pflanzen, Heinrich-Heine-Universitat 1, Universitatsstrasse, D-40225 Dusseldorf, Germany
| | - Andrew H Paterson
- Plant Genome Mapping Laboratory, University of Georgia, Athens, GA 30602, USA
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
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Hennen-Bierwagen TA, Lin Q, Grimaud F, Planchot V, Keeling PL, James MG, Myers AM. Proteins from multiple metabolic pathways associate with starch biosynthetic enzymes in high molecular weight complexes: a model for regulation of carbon allocation in maize amyloplasts. PLANT PHYSIOLOGY 2009; 149:1541-59. [PMID: 19168640 PMCID: PMC2649383 DOI: 10.1104/pp.109.135293] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Starch biosynthetic enzymes from maize (Zea mays) and wheat (Triticum aestivum) amyloplasts exist in cell extracts in high molecular weight complexes; however, the nature of those assemblies remains to be defined. This study tested the interdependence of the maize enzymes starch synthase IIa (SSIIa), SSIII, starch branching enzyme IIb (SBEIIb), and SBEIIa for assembly into multisubunit complexes. Mutations that eliminated any one of those proteins also prevented the others from assembling into a high molecular mass form of approximately 670 kD, so that SSIII, SSIIa, SBEIIa, and SBEIIb most likely all exist together in the same complex. SSIIa, SBEIIb, and SBEIIa, but not SSIII, were also interdependent for assembly into a complex of approximately 300 kD. SSIII, SSIIa, SBEIIa, and SBEIIb copurified through successive chromatography steps, and SBEIIa, SBEIIb, and SSIIa coimmunoprecipitated with SSIII in a phosphorylation-dependent manner. SBEIIa and SBEIIb also were retained on an affinity column bearing a specific conserved fragment of SSIII located outside of the SS catalytic domain. Additional proteins that copurified with SSIII in multiple biochemical methods included the two known isoforms of pyruvate orthophosphate dikinase (PPDK), large and small subunits of ADP-glucose pyrophosphorylase, and the sucrose synthase isoform SUS-SH1. PPDK and SUS-SH1 required SSIII, SSIIa, SBEIIa, and SBEIIb for assembly into the 670-kD complex. These complexes may function in global regulation of carbon partitioning between metabolic pathways in developing seeds.
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Danker T, Dreesen B, Offermann S, Horst I, Peterhänsel C. Developmental information but not promoter activity controls the methylation state of histone H3 lysine 4 on two photosynthetic genes in maize. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2008; 53:465-74. [PMID: 18179650 DOI: 10.1111/j.1365-313x.2007.03352.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
We have investigated the establishment of histone H3 methylation with respect to environmental and developmental signals for two key genes associated with C4 photosynthesis in maize. Tri-methylation of histone H3 lysine 4 (H3K4) in roots and leaves was shown to be controlled by autonomous cell-type-specific developmental signals that are independent of illumination and therefore independent of the initiation of transcription. Di- and mono-methylation of H3K4 act antagonistically to this process. The modifications were already established in etiolated seedlings, and remained stable when genes were inactivated by dark treatment or pharmaceutical inhibition of transcription. Constitutive di-methylation of H3K9 was concomitantly detected at specific gene positions. The data support a histone code model whereby cell-type-specific signals induce the formation of a chromatin structure that potentiates gene activation by environmental cues.
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Affiliation(s)
- Tanja Danker
- Rheinisch-Westfälische Hochschule Aachen, Biology I, 52056 Aachen, Germany
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Gordon JM, Polle JEW. Ultrahigh bioproductivity from algae. Appl Microbiol Biotechnol 2007; 76:969-75. [PMID: 17646982 DOI: 10.1007/s00253-007-1102-x] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2007] [Revised: 06/26/2007] [Accepted: 06/26/2007] [Indexed: 10/23/2022]
Abstract
The potential for dramatic increases in bioproductivity in algal photobioreactors relative to current biomass approaches, e.g., for converting sunlight into biofuels, by an unorthodox integration of photonics and biotechnologies is described. The key to greater biomass yields--projected as high as 100 g dry weight m(-2) h(-1)-is a pronounced heightening of algal flux tolerance, achieved by tailoring the photonic temporal, spectral and intensity characteristics with pulsed light-emitting diodes. Such tailored photonic input is applied in concert with thin-channel ultradense culture photobioreactors with flow patterns that produce rapid light/dark algae exposure cycles. The artificial-light scheme is globally feasible only with electricity generated from renewables. Recent advances in ultra-efficient concentrator photovoltaics, as well as high-performance light-emitting diodes, create a practical reality for converting sunlight into pulsed red light and delivering it to indoor photobioreactors, with characteristic pulse times and intensities optimally suited to the rate-limiting dark reactions of photosynthesis. Cellular engineering built upon recent progress in modifying algal chlorophyll antenna size, in combination with metabolic engineering, could further enhance bioproductivity. The proposed strategy requires no major advances for implementation and adopts existing technologies.
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Affiliation(s)
- Jeffrey M Gordon
- Department of Solar Energy and Environmental Physics, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 84990, Israel.
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Christin PA, Salamin N, Savolainen V, Duvall MR, Besnard G. C4 Photosynthesis Evolved in Grasses via Parallel Adaptive Genetic Changes. Curr Biol 2007; 17:1241-7. [PMID: 17614282 DOI: 10.1016/j.cub.2007.06.036] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2007] [Revised: 06/04/2007] [Accepted: 06/12/2007] [Indexed: 10/23/2022]
Abstract
Phenotypic convergence is a widespread and well-recognized evolutionary phenomenon. However, the responsible molecular mechanisms remain often unknown mainly because the genes involved are not identified. A well-known example of physiological convergence is the C4 photosynthetic pathway, which evolved independently more than 45 times [1]. Here, we address the question of the molecular bases of the C4 convergent phenotypes in grasses (Poaceae) by reconstructing the evolutionary history of genes encoding a C4 key enzyme, the phosphoenolpyruvate carboxylase (PEPC). PEPC genes belong to a multigene family encoding distinct isoforms of which only one is involved in C4 photosynthesis [2]. By using phylogenetic analyses, we showed that grass C4 PEPCs appeared at least eight times independently from the same non-C4 PEPC. Twenty-one amino acids evolved under positive selection and converged to similar or identical amino acids in most of the grass C4 PEPC lineages. This is the first record of such a high level of molecular convergent evolution, illustrating the repeatability of evolution. These amino acids were responsible for a strong phylogenetic bias grouping all C4 PEPCs together. The C4-specific amino acids detected must be essential for C4 PEPC enzymatic characteristics, and their identification opens new avenues for the engineering of the C4 pathway in crops.
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Affiliation(s)
- Pascal-Antoine Christin
- Department of Ecology and Evolution, Biophore, University of Lausanne, 1015 Lausanne, Switzerland.
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Rao SK, Fukayama H, Reiskind JB, Miyao M, Bowes G. Identification of C4 responsive genes in the facultative C4 plant Hydrilla verticillata. PHOTOSYNTHESIS RESEARCH 2006; 88:173-83. [PMID: 16622782 DOI: 10.1007/s11120-006-9049-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Accepted: 01/30/2006] [Indexed: 05/08/2023]
Abstract
The aquatic monocot Hydrilla verticillata (L.f.) Royle is a well-documented facultative C4 NADP-malic enzyme species in which the C4 and Calvin cycles operate in the same cell with the specific carboxylases confined to the cytosol and chloroplast, respectively. Several key components had already been characterized at the molecular level, thus the purpose of this study was to begin to identify other, less obvious, elements that may be necessary for a functional single-cell C4 system. Using differential display, mRNA populations from C3 and C4 H. verticillata leaves were screened and expression profiles compared. From this study, 65 clones were isolated and subjected to a customized macroarray analysis; 25 clones were found to be upregulated in C4 leaves. Northern and semi-quantitative RT-PCR analyses were used for confirmation. From these screenings, 13 C4 upregulated genes were identified. Among these one encoded a previously recognized C4 phosphoenolpyruvate carboxylase, and two encoded distinct pyruvate orthophosphate dikinase isoforms, new findings for H. verticillata. Genes that encode a transporter, an aminotransferase and two chaperonins were also upregulated. Twelve false positives, mostly housekeeping genes, were determined from the Northern/semi-quantitative RT-PCR analyses. Sequence data obtained in this study are listed in the dbEST database (DV216698 to DV216767). As a single-cell C4 system that lacks Kranz anatomy, a better understanding of how H. verticillata operates may facilitate the design of a transgenic C4 system in a C3 crop species.
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Affiliation(s)
- Srinath K Rao
- Department of Botany, University of Florida, Gainesville, FL 32611-8526, USA
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Mitchell PL, Sheehy JE. Supercharging rice photosynthesis to increase yield. THE NEW PHYTOLOGIST 2006; 171:688-93. [PMID: 16918541 DOI: 10.1111/j.1469-8137.2006.01855.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
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Majeran W, Cai Y, Sun Q, van Wijk KJ. Functional differentiation of bundle sheath and mesophyll maize chloroplasts determined by comparative proteomics. THE PLANT CELL 2005; 17:3111-40. [PMID: 16243905 PMCID: PMC1276033 DOI: 10.1105/tpc.105.035519] [Citation(s) in RCA: 180] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2005] [Revised: 09/05/2005] [Accepted: 09/24/2005] [Indexed: 05/05/2023]
Abstract
Chloroplasts of maize (Zea mays) leaves differentiate into specific bundle sheath (BS) and mesophyll (M) types to accommodate C4 photosynthesis. Consequences for other plastid functions are not well understood but are addressed here through a quantitative comparative proteome analysis of purified M and BS chloroplast stroma. Three independent techniques were used, including cleavable stable isotope coded affinity tags. Enzymes involved in lipid biosynthesis, nitrogen import, and tetrapyrrole and isoprenoid biosynthesis are preferentially located in the M chloroplasts. By contrast, enzymes involved in starch synthesis and sulfur import preferentially accumulate in BS chloroplasts. The different soluble antioxidative systems, in particular peroxiredoxins, accumulate at higher levels in M chloroplasts. We also observed differential accumulation of proteins involved in expression of plastid-encoded proteins (e.g., EF-Tu, EF-G, and mRNA binding proteins) and thylakoid formation (VIPP1), whereas others were equally distributed. Enzymes related to the C4 shuttle, the carboxylation and regeneration phase of the Calvin cycle, and several regulators (e.g., CP12) distributed as expected. However, enzymes involved in triose phosphate reduction and triose phosphate isomerase are primarily located in the M chloroplasts, indicating that the M-localized triose phosphate shuttle should be viewed as part of the BS-localized Calvin cycle, rather than a parallel pathway.
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Affiliation(s)
- Wojciech Majeran
- Department of Plant Biology, Cornell University, Ithaca, New York 14853, USA
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Thompson V. Associative nitrogen fixation, C4 photosynthesis, and the evolution of spittlebugs (Hemiptera: Cercopidae) as major pests of neotropical sugarcane and forage grasses. BULLETIN OF ENTOMOLOGICAL RESEARCH 2004; 94:189-200. [PMID: 15191620 DOI: 10.1079/ber2004293] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Neotropical grass-feeding spittlebugs of several genera are important pests of pasture grasses from the southeastern USA to northern Argentina, and of sugarcane from southern Mexico to southern Brazil, causing estimated reductions of up to 70% in yield and estimated monetary losses of 840-2100 million US dollars annually. With few exceptions, the species badly damaged by these spittlebugs are introduced C4 grasses that exhibit associative nitrogen fixation. This study synthesizes evidence that the pest status of many tropical and subtropical grass-feeding spittlebugs is linked to associative N-fixation in their C4 hosts. Recognition that associative N-fixation is a major factor in spittlebug host preferences should deepen understanding of spittlebug agricultural ecology and facilitate efforts to combat spittlebug pests. In particular, spittlebugs should be susceptible to manipulation of xylem transport solutes. However, reduction of nitrate fertilizer rates, increase in ammonium fertilizer rates, or enhancement of associative N-fixation as a consequence of genetic engineering could make hosts more susceptible to spittlebug attack. Because of their predilection for C4 grasses, spittlebugs present a clear counterexample to the hypothesis that herbivores prefer C3 plants to C4 plants. Finally, it appears that declines in atmospheric carbon dioxide levels during recent geological history promoted the proliferation of C4 grasses. This, compounded by human agricultural activities, has driven an ecological and evolutionary radiation of grass-feeding spittlebugs that presents continuing opportunities for the evolution of spittlebug pests.
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Affiliation(s)
- V Thompson
- School of Science and Mathematics, Roosevelt University, Chicago, Illinois 60605, USA.
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Abstract
C4 photosynthesis is a series of anatomical and biochemical modifications that concentrate CO2 around the carboxylating enzyme Rubisco, thereby increasing photosynthetic efficiency in conditions promoting high rates of photorespiration. The C4 pathway independently evolved over 45 times in 19 families of angiosperms, and thus represents one of the most convergent of evolutionary phenomena. Most origins of C4 photosynthesis occurred in the dicots, with at least 30 lineages. C4 photosynthesis first arose in grasses, probably during the Oligocene epoch (24-35 million yr ago). The earliest C4 dicots are likely members of the Chenopodiaceae dating back 15-21 million yr; however, most C4 dicot lineages are estimated to have appeared relatively recently, perhaps less than 5 million yr ago. C4 photosynthesis in the dicots originated in arid regions of low latitude, implicating combined effects of heat, drought and/or salinity as important conditions promoting C4 evolution. Low atmospheric CO2 is a significant contributing factor, because it is required for high rates of photorespiration. Consistently, the appearance of C4 plants in the evolutionary record coincides with periods of increasing global aridification and declining atmospheric CO2 . Gene duplication followed by neo- and nonfunctionalization are the leading mechanisms for creating C4 genomes, with selection for carbon conservation traits under conditions promoting high photorespiration being the ultimate factor behind the origin of C4 photosynthesis. Contents Summary 341 I. Introduction 342 II. What is C4 photosynthesis? 343 III. Why did C4 photosynthesis evolve? 347 IV. Evolutionary lineages of C4 photosynthesis 348 V. Where did C4 photosynthesis evolve? 350 VI. How did C4 photosynthesis evolve? 352 VII. Molecular evolution of C4 photosynthesis 361 VIII. When did C4 photosynthesis evolve 362 IX. The rise of C4 photosynthesis in relation to climate and CO2 363 X. Final thoughts: the future evolution of C4 photosynthesis 365 Acknowledgements 365 References 365.
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Affiliation(s)
- Rowan F Sage
- Department of Botany, University of Toronto, 25 Willcocks Street, Toronto, Ontario M5S 3B2, Canada
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Taniguchi Y, Nagasaki J, Kawasaki M, Miyake H, Sugiyama T, Taniguchi M. Differentiation of dicarboxylate transporters in mesophyll and bundle sheath chloroplasts of maize. PLANT & CELL PHYSIOLOGY 2004; 45:187-200. [PMID: 14988489 DOI: 10.1093/pcp/pch022] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
In NADP-malic enzyme-type C(4) plants such as maize (Zea mays L.), efficient transport of oxaloacetate and malate across the inner envelope membranes of chloroplasts is indispensable. We isolated four maize cDNAs, ZmpOMT1 and ZmpDCT1 to 3, encoding orthologs of plastidic 2-oxoglutarate/malate and general dicarboxylate transporters, respectively. Their transcript levels were upregulated by light in a cell-specific manner; ZmpOMT1 and ZmpDCT1 were expressed in the mesophyll cell (MC) and ZmpDCT2 and 3 were expressed in the bundle sheath cell (BSC). The recombinant ZmpOMT1 protein expressed in yeast could transport malate and 2-oxoglutarate but not glutamate. By contrast, the recombinant ZmpDCT1 and 2 proteins transported 2-oxoglutarate and glutamate at similar affinities in exchange for malate. The recombinant proteins could also transport oxaloacetate at the same binding sites as those for the dicarboxylates. In particular, ZmpOMT1 transported oxaloacetate at a higher efficiency than malate or 2-oxoglutarate. We also compared the activities of oxaloacetate transport between MC and BSC chloroplasts from maize leaves. The K(m) value for oxaloacetate in MC chloroplasts was one order of magnitude lower than that in BSC chloroplasts, and was close to that determined with the recombinant ZmpOMT1 protein. Southern analysis revealed that maize has a single OMT gene. These findings suggest that ZmpOMT1 participates in the import of oxaloacetate into MC chloroplasts in exchange for stromal malate. In BSC chloroplasts, ZmpDCT2 and/or ZmpDCT3 were expected to import malate that is transported from MC.
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Affiliation(s)
- Yojiro Taniguchi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, 464-8601 Japan.
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Metabolic consequences of overproduction of phosphoenolpyruvate carboxylase in C3 plants. Arch Biochem Biophys 2003; 414:197-203. [PMID: 12781771 DOI: 10.1016/s0003-9861(03)00117-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Phosphoenolpyruvate carboxylase (PEPC) has a variety of functions in plants, including a major anaplerotic role in replenishing the tricarboxylic acid cycle with intermediates to meet the demand of carbon skeletons for synthesis of organic acids and amino acids. Various transgenic C3 plants that overproduce PEPC have been produced and analyzed in detail. The results indicate that foreign PEPC is under the control of the regulatory mechanisms intrinsic to the host plant and down-regulated so as not to cause detrimental metabolic effects, although the anaplerotic reaction is slightly enhanced by the foreign PEPC. By use of foreign PEPCs that can avert such regulation, metabolic flow is largely directed toward synthesis of organic acids and amino acids. Observations with transgenic C3 plants also shed light on the interrelation among various metabolic pathways inside the cell.
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