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Li Y, Jian Y, Mao Y, Meng F, Shao Z, Wang T, Zheng J, Wang Q, Liu L. "Omics" insights into plastid behavior toward improved carotenoid accumulation. FRONTIERS IN PLANT SCIENCE 2022; 13:1001756. [PMID: 36275568 PMCID: PMC9583013 DOI: 10.3389/fpls.2022.1001756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
Plastids are a group of diverse organelles with conserved carotenoids synthesizing and sequestering functions in plants. They optimize the carotenoid composition and content in response to developmental transitions and environmental stimuli. In this review, we describe the turbulence and reforming of transcripts, proteins, and metabolic pathways for carotenoid metabolism and storage in various plastid types upon organogenesis and external influences, which have been studied using approaches including genomics, transcriptomics, proteomics, and metabonomics. Meanwhile, the coordination of plastid signaling and carotenoid metabolism including the effects of disturbed carotenoid biosynthesis on plastid morphology and function are also discussed. The "omics" insight extends our understanding of the interaction between plastids and carotenoids and provides significant implications for designing strategies for carotenoid-biofortified crops.
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Affiliation(s)
- Yuanyuan Li
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Yue Jian
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Yuanyu Mao
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Fanliang Meng
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Zhiyong Shao
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Tonglin Wang
- Hangzhou Academy of Agricultural Sciences, Hangzhou, China
| | - Jirong Zheng
- Hangzhou Academy of Agricultural Sciences, Hangzhou, China
| | - Qiaomei Wang
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Lihong Liu
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
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Guo H, Ryan JC, Song X, Mallet A, Zhang M, Pabst V, Decrulle AL, Ejsmont P, Wintermute EH, Lindner AB. Spatial engineering of E. coli with addressable phase-separated RNAs. Cell 2022; 185:3823-3837.e23. [PMID: 36179672 DOI: 10.1016/j.cell.2022.09.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 04/25/2022] [Accepted: 09/06/2022] [Indexed: 01/26/2023]
Abstract
Biochemical processes often require spatial regulation and specific microenvironments. The general lack of organelles in bacteria limits the potential of bioengineering complex intracellular reactions. Here, we demonstrate synthetic membraneless organelles in Escherichia coli termed transcriptionally engineered addressable RNA solvent droplets (TEARS). TEARS are assembled from RNA-binding protein recruiting domains fused to poly-CAG repeats that spontaneously drive liquid-liquid phase separation from the bulk cytoplasm. Targeting TEARS with fluorescent proteins revealed multilayered structures with composition and reaction robustness governed by non-equilibrium dynamics. We show that TEARS provide organelle-like bioprocess isolation for sequestering biochemical pathways, controlling metabolic branch points, buffering mRNA translation rates, and scaffolding protein-protein interactions. We anticipate TEARS to be a simple and versatile tool for spatially controlling E. coli biochemistry. Particularly, the modular design of TEARS enables applications without expression fine-tuning, simplifying the design-build-test cycle of bioengineering.
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Affiliation(s)
- Haotian Guo
- Université de Paris, INSERM U1284, Center for Research and Interdisciplinarity (CRI), 75006 Paris, France.
| | - Joseph C Ryan
- Université de Paris, INSERM U1284, Center for Research and Interdisciplinarity (CRI), 75006 Paris, France
| | - Xiaohu Song
- Université de Paris, INSERM U1284, Center for Research and Interdisciplinarity (CRI), 75006 Paris, France
| | - Adeline Mallet
- Ultrastructural BioImaging UTechS, C2RT, Institut Pasteur, 28 rue du Dr Roux, 75015 Paris, France
| | - Mengmeng Zhang
- Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Science, Shenzhen, China
| | - Victor Pabst
- Université de Paris, INSERM U1284, Center for Research and Interdisciplinarity (CRI), 75006 Paris, France
| | - Antoine L Decrulle
- Université de Paris, INSERM U1284, Center for Research and Interdisciplinarity (CRI), 75006 Paris, France
| | - Paulina Ejsmont
- Université de Paris, INSERM U1284, Center for Research and Interdisciplinarity (CRI), 75006 Paris, France
| | - Edwin H Wintermute
- Université de Paris, INSERM U1284, Center for Research and Interdisciplinarity (CRI), 75006 Paris, France
| | - Ariel B Lindner
- Université de Paris, INSERM U1284, Center for Research and Interdisciplinarity (CRI), 75006 Paris, France.
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Welsch R, Li L. Golden Rice—Lessons learned for inspiring future metabolic engineering strategies and synthetic biology solutions. Methods Enzymol 2022; 671:1-29. [DOI: 10.1016/bs.mie.2022.03.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Sun T, Li L. Toward the 'golden' era: The status in uncovering the regulatory control of carotenoid accumulation in plants. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2020; 290:110331. [PMID: 31779888 DOI: 10.1016/j.plantsci.2019.110331] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/21/2019] [Accepted: 11/01/2019] [Indexed: 05/17/2023]
Abstract
Carotenoids are essential pigments to plants and important natural products to humans. Carotenoids as both primary and specialized metabolites fulfill multifaceted functions in plants. As such, carotenoid accumulation (a net process of biosynthesis, degradation and sequestration) is subjected to complicated regulation throughout plant life cycle in response to developmental and environmental signals. Investigation of transcriptional regulation of carotenoid metabolic genes remains the focus in understanding the regulatory control of carotenoid accumulation. While discovery of bona fide carotenoid metabolic regulators is still challenging, the recent progress of identification of various transcription factors and regulators helps us to construct hierarchical regulatory network of carotenoid accumulation. The elucidation of carotenoid regulatory mechanisms at protein level and in chromoplast provides some insights into post-translational regulation of carotenogenic enzymes and carotenoid sequestration in plastid sink. This review briefly describes the pathways and main flux-controlling steps for carotenoid accumulation in plants. It highlights our recent understanding of the regulatory mechanisms underlying carotenoid accumulation at both transcriptional and post-translational levels. It also discusses the opportunities to expand toolbox for further shedding light upon the intrinsic regulation of carotenoid accumulation in plants.
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Affiliation(s)
- Tianhu Sun
- Robert W Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, New York, 14853, USA; Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, New York, 14853, USA
| | - Li Li
- Robert W Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, New York, 14853, USA; Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, New York, 14853, USA.
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Knudsen C, Gallage NJ, Hansen CC, Møller BL, Laursen T. Dynamic metabolic solutions to the sessile life style of plants. Nat Prod Rep 2019; 35:1140-1155. [PMID: 30324199 PMCID: PMC6254060 DOI: 10.1039/c8np00037a] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Plants are sessile organisms. To compensate for not being able to escape when challenged by unfavorable growth conditions, pests or herbivores, plants have perfected their metabolic plasticity by having developed the capacity for on demand dynamic biosynthesis and storage of a plethora of phytochemicals.
Covering: up to 2018 Plants are sessile organisms. To compensate for not being able to escape when challenged by unfavorable growth conditions, pests or herbivores, plants have perfected their metabolic plasticity by having developed the capacity for on demand synthesis of a plethora of phytochemicals to specifically respond to the challenges arising during plant ontogeny. Key steps in the biosynthesis of phytochemicals are catalyzed by membrane-bound cytochrome P450 enzymes which in plants constitute a superfamily. In planta, the P450s may be organized in dynamic enzyme clusters (metabolons) and the genes encoding the P450s and other enzymes in a specific pathway may be clustered. Metabolon formation facilitates transfer of substrates between sequential enzymes and therefore enables the plant to channel the flux of general metabolites towards biosynthesis of specific phytochemicals. In the plant cell, compartmentalization of the operation of specific biosynthetic pathways in specialized plastids serves to avoid undesired metabolic cross-talk and offers distinct storage sites for molar concentrations of specific phytochemicals. Liquid–liquid phase separation may lead to formation of dense biomolecular condensates within the cytoplasm or vacuole allowing swift activation of the stored phytochemicals as required upon pest or herbivore attack. The molecular grid behind plant plasticity offers an endless reservoir of functional modules, which may be utilized as a synthetic biology tool-box for engineering of novel biological systems based on rational design principles. In this review, we highlight some of the concepts used by plants to coordinate biosynthesis and storage of phytochemicals.
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Affiliation(s)
- Camilla Knudsen
- Plant Biochemistry Laboratory, Department of Plant and Environmental Science, University of Copenhagen, DK-1871 Frederiksberg C, Denmark.
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Welsch R, Zhou X, Koschmieder J, Schlossarek T, Yuan H, Sun T, Li L. Characterization of Cauliflower OR Mutant Variants. FRONTIERS IN PLANT SCIENCE 2019; 10:1716. [PMID: 32038686 PMCID: PMC6985574 DOI: 10.3389/fpls.2019.01716] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 12/05/2019] [Indexed: 05/19/2023]
Abstract
Cauliflower Orange (Or) mutant is characterized by high level of β-carotene in its curd. Or mutation affects the OR protein that was shown to be involved in the posttranslational control of phytoene synthase (PSY), a major rate-limiting enzyme of carotenoid biosynthesis, and in maintaining PSY proteostasis with the plastid Clp protease system. A transposon integration into the cauliflower wild-type Or gene (BoOR-wt) results in the formation of three differently spliced transcripts. One of them is characterized by insertion (BoOR-Ins), while the other two have exon-skipping deletions (BoOR-Del and BoOR-LD). We investigated the properties of individual BoOR variants and examined their effects on carotenoid accumulation. Using the yeast split-ubiquitin system, we showed that all variants were able to form OR dimers except BoOR-LD. The deletion in BoOR-LD eliminated the first of two adjacent transmembrane domains and was predicted to result in a misplacement of the C-terminal zinc finger domain to the opposite side of membrane, thus preventing OR dimerization. As interaction with PSY is mediated by the N-terminus of BoOR, which remains unaffected after splicing, all BoOR variants including BoOR-LD maintained interactions with PSY. Expression of individual BoOR mutant variants in Arabidopsis revealed that their protein stability varied greatly. While expression of BoOR-Del and BoOR-Ins resulted in increased BoOR protein levels as BoOR-wt, minimal amounts of BoOR-LD protein accumulated. Carotenoid accumulation showed correlated changes in calli of Arabidopsis expressing these variants. Furthermore, we found that OR also functions in E. coli to increase the proportion of native, enzymatically active PSY from plants upon co-expression, but not of bacterial phytoene synthase CrtB. Taken together, these results suggest that OR dimerization is required for OR stability in planta and that the simultaneous presence of PSY interaction-domains in both OR and PSY proteins is required for the holdase function of OR. The more pronounced effect of simultaneous expression of all BoOR variants in cauliflower Or mutant compared with individual overexpression on carotenoid accumulation suggests an enhanced activity with possible formation of various BoOR heterodimers.
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Affiliation(s)
- Ralf Welsch
- Faculty of Biology II, University of Freiburg, Freiburg, Germany
- *Correspondence: Ralf Welsch, ; Li Li,
| | - Xiangjun Zhou
- Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, NY, United States
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, United States
| | | | - Tim Schlossarek
- Faculty of Biology II, University of Freiburg, Freiburg, Germany
| | - Hui Yuan
- Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, NY, United States
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, United States
| | - Tianhu Sun
- Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, NY, United States
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, United States
| | - Li Li
- Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, NY, United States
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, United States
- *Correspondence: Ralf Welsch, ; Li Li,
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de Souza VF, Niinemets Ü, Rasulov B, Vickers CE, Duvoisin Júnior S, Araújo WL, Gonçalves JFDC. Alternative Carbon Sources for Isoprene Emission. TRENDS IN PLANT SCIENCE 2018; 23:1081-1101. [PMID: 30472998 PMCID: PMC6354897 DOI: 10.1016/j.tplants.2018.09.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 09/03/2018] [Accepted: 09/25/2018] [Indexed: 05/07/2023]
Abstract
Isoprene and other plastidial isoprenoids are produced primarily from recently assimilated photosynthates via the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway. However, when environmental conditions limit photosynthesis, a fraction of carbon for MEP pathway can come from extrachloroplastic sources. The flow of extrachloroplastic carbon depends on the species and on leaf developmental and environmental conditions. The exchange of common phosphorylated intermediates between the MEP pathway and other metabolic pathways can occur via plastidic phosphate translocators. C1 and C2 carbon intermediates can contribute to chloroplastic metabolism, including photosynthesis and isoprenoid synthesis. Integration of these metabolic processes provide an example of metabolic flexibility, and results in the synthesis of primary metabolites for plant growth and secondary metabolites for plant defense, allowing effective use of environmental resources under multiple stresses.
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Affiliation(s)
- Vinícius Fernandes de Souza
- Laboratory of Plant Physiology and Biochemistry, National Institute for Amazonian Research (INPA), Manaus, AM 69011-970, Brazil; University of Amazonas State, Manaus, AM 69050-010, Brazil
| | - Ülo Niinemets
- Department of Crop Science and Plant Biology, Estonian University of Life Sciences, Tartu 51006, Estonia; Estonian Academy of Sciences, 10130 Tallinn, Estonia
| | - Bahtijor Rasulov
- Department of Crop Science and Plant Biology, Estonian University of Life Sciences, Tartu 51006, Estonia; Institute of Technology, University of Tartu, Tartu, Estonia
| | - Claudia E Vickers
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, St Lucia, QLD 4072, Australia; Commonwealth Scientific and Industrial Research Organisation (CSIRO) Synthetic Biology Future Science Platform, EcoSciences Precinct, Brisbane, QLD 4001, Australia
| | | | - Wagner L Araújo
- Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900 Viçosa, MG, Brazil
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Welsch R, Zhou X, Yuan H, Álvarez D, Sun T, Schlossarek D, Yang Y, Shen G, Zhang H, Rodriguez-Concepcion M, Thannhauser TW, Li L. Clp Protease and OR Directly Control the Proteostasis of Phytoene Synthase, the Crucial Enzyme for Carotenoid Biosynthesis in Arabidopsis. MOLECULAR PLANT 2018; 11:149-162. [PMID: 29155321 DOI: 10.1016/j.molp.2017.11.003] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 10/01/2017] [Accepted: 11/10/2017] [Indexed: 05/17/2023]
Abstract
Phytoene synthase (PSY) is the crucial plastidial enzyme in the carotenoid biosynthetic pathway. However, its post-translational regulation remains elusive. Likewise, Clp protease constitutes a central part of the plastid protease network, but its substrates for degradation are not well known. In this study, we report that PSY is a substrate of the Clp protease. PSY was uncovered to physically interact with various Clp protease subunits (i.e., ClpS1, ClpC1, and ClpD). High levels of PSY and several other carotenogenic enzyme proteins overaccumulate in the clpc1, clpp4, and clpr1-2 mutants. The overaccumulated PSY was found to be partially enzymatically active. Impairment of Clp activity in clpc1 results in a reduced rate of PSY protein turnover, further supporting the role of Clp protease in degrading PSY protein. On the other hand, the ORANGE (OR) protein, a major post-translational regulator of PSY with holdase chaperone activity, enhances PSY protein stability and increases the enzymatically active proportion of PSY in clpc1, counterbalancing Clp-mediated proteolysis in maintaining PSY protein homeostasis. Collectively, these findings provide novel insights into the quality control of plastid-localized proteins and establish a hitherto unidentified post-translational regulatory mechanism of carotenogenic enzymes in modulating carotenoid biosynthesis in plants.
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Affiliation(s)
- Ralf Welsch
- University of Freiburg, Faculty of Biology II, 79104 Freiburg, Germany.
| | - Xiangjun Zhou
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA; Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA
| | - Hui Yuan
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA; Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA
| | - Daniel Álvarez
- University of Freiburg, Faculty of Biology II, 79104 Freiburg, Germany
| | - Tianhu Sun
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA; Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA
| | | | - Yong Yang
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA
| | - Guoxin Shen
- Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Hong Zhang
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA
| | - Manuel Rodriguez-Concepcion
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, Barcelona, Spain
| | - Theodore W Thannhauser
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA
| | - Li Li
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA; Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA.
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Sun T, Yuan H, Cao H, Yazdani M, Tadmor Y, Li L. Carotenoid Metabolism in Plants: The Role of Plastids. MOLECULAR PLANT 2018; 11:58-74. [PMID: 28958604 DOI: 10.1016/j.molp.2017.09.010] [Citation(s) in RCA: 324] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 09/02/2017] [Accepted: 09/13/2017] [Indexed: 05/17/2023]
Abstract
Carotenoids are indispensable to plants and critical in human diets. Plastids are the organelles for carotenoid biosynthesis and storage in plant cells. They exist in various types, which include proplastids, etioplasts, chloroplasts, amyloplasts, and chromoplasts. These plastids have dramatic differences in their capacity to synthesize and sequester carotenoids. Clearly, plastids play a central role in governing carotenogenic activity, carotenoid stability, and pigment diversity. Understanding of carotenoid metabolism and accumulation in various plastids expands our view on the multifaceted regulation of carotenogenesis and facilitates our efforts toward developing nutrient-enriched food crops. In this review, we provide a comprehensive overview of the impact of various types of plastids on carotenoid biosynthesis and accumulation, and discuss recent advances in our understanding of the regulatory control of carotenogenesis and metabolic engineering of carotenoids in light of plastid types in plants.
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Affiliation(s)
- Tianhu Sun
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA; Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA
| | - Hui Yuan
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA; Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA
| | - Hongbo Cao
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA; College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Mohammad Yazdani
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA; Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA
| | - Yaakov Tadmor
- Plant Science Institute, Israeli Agricultural Research Organization, Newe Yaar Research Center, P.O. Box 1021, Ramat Yishai 30095, Israel
| | - Li Li
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA; Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA.
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Abstract
A substantial proportion of the dazzling diversity of colors displayed by living organisms throughout the tree of life is determined by the presence of carotenoids, which most often provide distinctive yellow, orange and red hues. These metabolites play fundamental roles in nature that extend far beyond their importance as pigments. In photosynthetic lineages, carotenoids are essential to sustain life, since they have been exploited to maximize light harvesting and protect the photosynthetic machinery from photooxidative stress. Consequently, photosynthetic organisms have evolved several mechanisms that adjust the carotenoid metabolism to efficiently cope with constantly fluctuating light environments. This chapter will focus on the current knowledge concerning the regulation of the carotenoid biosynthetic pathway in leaves, which are the primary photosynthetic organs of most land plants.
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Abstract
Carotenoids are the most important biocolor isoprenoids responsible for yellow, orange and red colors found in nature. In plants, they are synthesized in plastids of photosynthetic and sink organs and are essential molecules for photosynthesis, photo-oxidative damage protection and phytohormone synthesis. Carotenoids also play important roles in human health and nutrition acting as vitamin A precursors and antioxidants. Biochemical and biophysical approaches in different plants models have provided significant advances in understanding the structural and functional roles of carotenoids in plants as well as the key points of regulation in their biosynthesis. To date, different plant models have been used to characterize the key genes and their regulation, which has increased the knowledge of the carotenoid metabolic pathway in plants. In this chapter a description of each step in the carotenoid synthesis pathway is presented and discussed.
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Affiliation(s)
| | - Claudia Stange
- Centro de Biología Molecular Vegetal, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago, Chile
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Ruiz-Sola MÁ, Coman D, Beck G, Barja MV, Colinas M, Graf A, Welsch R, Rütimann P, Bühlmann P, Bigler L, Gruissem W, Rodríguez-Concepción M, Vranová E. Arabidopsis GERANYLGERANYL DIPHOSPHATE SYNTHASE 11 is a hub isozyme required for the production of most photosynthesis-related isoprenoids. THE NEW PHYTOLOGIST 2016; 209:252-264. [PMID: 26224411 DOI: 10.1111/nph.13580] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 06/30/2015] [Indexed: 05/21/2023]
Abstract
Most plastid isoprenoids, including photosynthesis-related metabolites such as carotenoids and the side chain of chlorophylls, tocopherols (vitamin E), phylloquinones (vitamin K), and plastoquinones, derive from geranylgeranyl diphosphate (GGPP) synthesized by GGPP synthase (GGPPS) enzymes. Seven out of 10 functional GGPPS isozymes in Arabidopsis thaliana reside in plastids. We aimed to address the function of different GGPPS paralogues for plastid isoprenoid biosynthesis. We constructed a gene co-expression network (GCN) using GGPPS paralogues as guide genes and genes from the upstream and downstream pathways as query genes. Furthermore, knock-out and/or knock-down ggpps mutants were generated and their growth and metabolic phenotypes were analyzed. Also, interacting protein partners of GGPPS11 were searched for. Our data showed that GGPPS11, encoding the only plastid isozyme essential for plant development, functions as a hub gene among GGPPS paralogues and is required for the production of all major groups of plastid isoprenoids. Furthermore, we showed that the GGPPS11 protein physically interacts with enzymes that use GGPP for the production of carotenoids, chlorophylls, tocopherols, phylloquinone, and plastoquinone. GGPPS11 is a hub isozyme required for the production of most photosynthesis-related isoprenoids. Both gene co-expression and protein-protein interaction likely contribute to the channeling of GGPP by GGPPS11.
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Affiliation(s)
- M Águila Ruiz-Sola
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, Barcelona, 08193, Spain
| | - Diana Coman
- Department of Biology, Plant Biotechnology, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland
| | - Gilles Beck
- Department of Biology, Plant Biotechnology, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland
| | - M Victoria Barja
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, Barcelona, 08193, Spain
| | - Maite Colinas
- Department of Biology, Plant Biotechnology, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland
| | - Alexander Graf
- Department of Biology, Plant Biotechnology, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland
| | - Ralf Welsch
- Faculty of Biology II, University of Freiburg, Freiburg, 79104, Germany
| | - Philipp Rütimann
- Department of Mathematics, Seminar for Statistics, ETH Zurich, Rämistrasse 101, Zurich, 8092, Switzerland
| | - Peter Bühlmann
- Department of Mathematics, Seminar for Statistics, ETH Zurich, Rämistrasse 101, Zurich, 8092, Switzerland
| | - Laurent Bigler
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, Zurich, 8057, Switzerland
| | - Wilhelm Gruissem
- Department of Biology, Plant Biotechnology, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland
| | - Manuel Rodríguez-Concepción
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, Barcelona, 08193, Spain
| | - Eva Vranová
- Department of Biology, Plant Biotechnology, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland
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Endow JK, Singhal R, Fernandez DE, Inoue K. Chaperone-assisted Post-translational Transport of Plastidic Type I Signal Peptidase 1. J Biol Chem 2015; 290:28778-91. [PMID: 26446787 DOI: 10.1074/jbc.m115.684829] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Indexed: 01/19/2023] Open
Abstract
Type I signal peptidase (SPase I) is an integral membrane Ser/Lys protease with one or two transmembrane domains (TMDs), cleaving transport signals off translocated precursor proteins. The catalytic domain of SPase I folds to form a hydrophobic surface and inserts into the lipid bilayers at the trans-side of the membrane. In bacteria, SPase I is targeted co-translationally, and the catalytic domain remains unfolded until it reaches the periplasm. By contrast, SPases I in eukaryotes are targeted post-translationally, requiring an alternative strategy to prevent premature folding. Here we demonstrate that two distinct stromal components are involved in post-translational transport of plastidic SPase I 1 (Plsp1) from Arabidopsis thaliana, which contains a single TMD. During import into isolated chloroplasts, Plsp1 was targeted to the membrane via a soluble intermediate in an ATP hydrolysis-dependent manner. Insertion of Plsp1 into isolated chloroplast membranes, by contrast, was found to occur by two distinct mechanisms. The first mechanism requires ATP hydrolysis and the protein conducting channel cpSecY1 and was strongly enhanced by exogenously added cpSecA1. The second mechanism was independent of nucleoside triphosphates and proteinaceous components but with a high frequency of mis-orientation. This unassisted insertion was inhibited by urea and stroma extract. During import-chase assays using intact chloroplasts, Plsp1 was incorporated into a soluble 700-kDa complex that co-migrated with the Cpn60 complex before inserting into the membrane. The TMD within Plsp1 was required for the cpSecA1-dependent insertion but was dispensable for association with the 700-kDa complex and also for unassisted membrane insertion. These results indicate cooperation of Cpn60 and cpSecA1 for proper membrane insertion of Plsp1 by cpSecY1.
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Affiliation(s)
- Joshua K Endow
- From the Department of Plant Sciences, University of California, Davis, California 95616 and
| | - Rajneesh Singhal
- the Department of Botany, University of Wisconsin, Madison, Wisconsin 53706
| | - Donna E Fernandez
- the Department of Botany, University of Wisconsin, Madison, Wisconsin 53706
| | - Kentaro Inoue
- From the Department of Plant Sciences, University of California, Davis, California 95616 and
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Arabidopsis OR proteins are the major posttranscriptional regulators of phytoene synthase in controlling carotenoid biosynthesis. Proc Natl Acad Sci U S A 2015; 112:3558-63. [PMID: 25675505 DOI: 10.1073/pnas.1420831112] [Citation(s) in RCA: 183] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Carotenoids are indispensable natural pigments to plants and humans. Phytoene synthase (PSY), the rate-limiting enzyme in the carotenoid biosynthetic pathway, and ORANGE (OR), a regulator of chromoplast differentiation and enhancer of carotenoid biosynthesis, represent two key proteins that control carotenoid biosynthesis and accumulation in plants. However, little is known about the mechanisms underlying their posttranscriptional regulation. Here we report that PSY and OR family proteins [Arabidopsis thaliana OR (AtOR) and AtOR-like] physically interacted with each other in plastids. We found that alteration of OR expression in Arabidopsis exerted minimal effect on PSY transcript abundance. However, overexpression of AtOR significantly increased the amount of enzymatically active PSY, whereas an ator ator-like double mutant exhibited a dramatically reduced PSY level. The results indicate that the OR proteins serve as the major posttranscriptional regulators of PSY. The ator or ator-like single mutant had little effect on PSY protein levels, which involves a compensatory mechanism and suggests partial functional redundancy. In addition, modification of PSY expression resulted in altered AtOR protein levels, corroborating a mutual regulation of PSY and OR. Carotenoid content showed a correlated change with OR-mediated PSY level, demonstrating the function of OR in controlling carotenoid biosynthesis by regulating PSY. Our findings reveal a novel mechanism by which carotenoid biosynthesis is controlled via posttranscriptional regulation of PSY in plants.
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Affiliation(s)
| | - Salim Al-Babili
- BESE Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Eleanore T. Wurtzel
- The Graduate School and University Center, The City University of New York, New York, New York, USA
- Department of Biological Sciences, Lehman College, The City University of New York, Bronx, New York, USA
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16
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Vitlin Gruber A, Nisemblat S, Azem A, Weiss C. The complexity of chloroplast chaperonins. TRENDS IN PLANT SCIENCE 2013; 18:688-94. [PMID: 24035661 DOI: 10.1016/j.tplants.2013.08.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Revised: 07/29/2013] [Accepted: 08/07/2013] [Indexed: 05/07/2023]
Abstract
Type I chaperonins are large oligomeric protein ensembles that are involved in the folding and assembly of other proteins. Chloroplast chaperonins and co-chaperonins exist in multiple copies of two distinct isoforms that can combine to form a range of labile oligomeric structures. This complex system increases the potential number of chaperonin substrates and possibilities for regulation. The incorporation of unique subunits into the oligomer can modify substrate specificity. Some subunits are upregulated in response to heat shock and some show organ-specific expression, whereas others possess additional functions that are unrelated to their role in protein folding. Accumulating evidence suggests that specific subunits have distinct roles in biogenesis of ribulose-1,5-bisphosphate carboxylase oxygenase (Rubisco).
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Affiliation(s)
- Anna Vitlin Gruber
- The George S. Wise Faculty of Life Sciences, Department of Biochemistry and Molecular Biology, Tel Aviv University, Ramat Aviv, Israel
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17
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Shumskaya M, Wurtzel ET. The carotenoid biosynthetic pathway: thinking in all dimensions. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2013; 208:58-63. [PMID: 23683930 PMCID: PMC3672397 DOI: 10.1016/j.plantsci.2013.03.012] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 03/15/2013] [Accepted: 03/19/2013] [Indexed: 05/19/2023]
Abstract
The carotenoid biosynthetic pathway serves manifold roles in plants related to photosynthesis, photoprotection, development, stress hormones, and various volatiles and signaling apocarotenoids. The pathway also produces compounds that impact human nutrition and metabolic products that contribute to fragrance and flavor of food and non-food crops. It is no surprise that the pathway has been a target of metabolic engineering, most prominently in the case of Golden Rice. The future success and predictability of metabolic engineering of carotenoids rests in the ability to target carotenoids for specific physiological purposes as well as to simultaneously modify carotenoids along with other desired traits. Here, we ask whether predictive metabolic engineering of the carotenoid pathway is indeed possible. Despite a long history of research on the pathway, at this point in time we can only describe the pathway as a parts list and have almost no knowledge of the location of the complete pathway, how it is assembled, and whether there exists any trafficking of the enzymes or the carotenoids themselves. We discuss the current state of knowledge regarding the "complete" pathway and make the argument that predictive metabolic engineering of the carotenoid pathway (and other pathways) will require investigation of the three dimensional state of the pathway as it may exist in plastids of different ultrastructures. Along with this message we point out the need to develop new types of visualization tools and resources that better reflect the dynamic nature of biosynthetic pathways.
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Affiliation(s)
- Maria Shumskaya
- Department of Biological Sciences, Lehman College, The City University of New York (CUNY), Bronx, NY 10468, USA
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18
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Akhtar TA, Matsuba Y, Schauvinhold I, Yu G, Lees HA, Klein SE, Pichersky E. The tomato cis-prenyltransferase gene family. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 73:640-52. [PMID: 23134568 DOI: 10.1111/tpj.12063] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Revised: 10/25/2012] [Accepted: 10/29/2012] [Indexed: 05/22/2023]
Abstract
cis-prenyltransferases (CPTs) are predicted to be involved in the synthesis of long-chain polyisoprenoids, all with five or more isoprene (C5) units. Recently, we identified a short-chain CPT, neryl diphosphate synthase (NDPS1), in tomato (Solanum lycopersicum). Here, we searched the tomato genome and identified and characterized its entire CPT gene family, which comprises seven members (SlCPT1-7, with NDPS1 designated as SlCPT1). Six of the SlCPT genes encode proteins with N-terminal targeting sequences, which, when fused to GFP, mediated GFP transport to the plastids of Arabidopsis protoplasts. The SlCPT3-GFP fusion protein was localized to the cytosol. Enzymatic characterization of recombinant SlCPT proteins demonstrated that SlCPT6 produces Z,Z-FPP, and SlCPT2 catalyzes the formation of nerylneryl diphosphate while SlCPT4, SlCPT5 and SlCPT7 synthesize longer-chain products (C25-C55). Although no in vitro activity was demonstrated for SlCPT3, its expression in the Saccharomyces cerevisiae dolichol biosynthesis mutant (rer2) complemented the temperature-sensitive growth defect. Transcripts of SlCPT2, SlCPT4, SlCPT5 and SlCPT7 are present at low levels in multiple tissues, SlCPT6 is exclusively expressed in red fruit and roots, and SlCPT1, SlCPT3 and SlCPT7 are highly expressed in trichomes. RNAi-mediated suppression of NDPS1 led to a large decrease in β-phellandrene (which is produced from neryl diphosphate), with greater reductions achieved with the general 35S promoter compared to the trichome-specific MKS1 promoter. Phylogenetic analysis revealed CPT gene families in both eudicots and monocots, and showed that all the short-chain CPT genes from tomato (SlCPT1, SlCPT2 and SlCPT6) are closely linked to terpene synthase gene clusters.
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Affiliation(s)
- Tariq A Akhtar
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
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19
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Quinlan RF, Shumskaya M, Bradbury LM, Beltrán J, Ma C, Kennelly EJ, Wurtzel ET. Synergistic interactions between carotene ring hydroxylases drive lutein formation in plant carotenoid biosynthesis. PLANT PHYSIOLOGY 2012; 160:204-14. [PMID: 22786888 PMCID: PMC3440199 DOI: 10.1104/pp.112.198556] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Accepted: 07/01/2012] [Indexed: 05/18/2023]
Abstract
Plant carotenoids play essential roles in photosynthesis, photoprotection, and as precursors to apocarotenoids. The plastid-localized carotenoid biosynthetic pathway is mediated by well-defined nucleus-encoded enzymes. However, there is a major gap in understanding the nature of protein interactions and pathway complexes needed to mediate carotenogenesis. In this study, we focused on carotene ring hydroxylation, which is performed by two structurally distinct classes of enzymes, the P450 CYP97A and CYP97C hydroxylases and the nonheme diiron HYD enzymes. The CYP97A and HYD enzymes both function in the hydroxylation of β-rings in carotenes, but we show that they are not functionally interchangeable. The formation of lutein, which involves hydroxylation of both β- and ε-rings, was shown to require the coexpression of CYP97A and CYP97C enzymes. These enzymes were also demonstrated to interact in vivo and in vitro, as determined using bimolecular fluorescence complementation and a pull-down assay, respectively. We discuss the role of specific hydroxylase enzyme interactions in promoting pathway flux and preventing the formation of pathway dead ends. These findings will facilitate efforts to manipulate carotenoid content and composition for improving plant adaptation to climate change and/or for enhancing nutritionally important carotenoids in food crops.
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Affiliation(s)
| | | | | | - Jesús Beltrán
- Department of Biological Sciences, Lehman College, City University of New York, Bronx, New York 10468 (R.F.Q., M.S., L.M.T.B., J.B., C.M., E.J.K., E.T.W.); and Graduate School and University Center, City University of New York, New York, New York 10016 (R.F.Q., J.B., E.J.K., E.T.W.)
| | | | - Edward J. Kennelly
- Department of Biological Sciences, Lehman College, City University of New York, Bronx, New York 10468 (R.F.Q., M.S., L.M.T.B., J.B., C.M., E.J.K., E.T.W.); and Graduate School and University Center, City University of New York, New York, New York 10016 (R.F.Q., J.B., E.J.K., E.T.W.)
| | - Eleanore T. Wurtzel
- Department of Biological Sciences, Lehman College, City University of New York, Bronx, New York 10468 (R.F.Q., M.S., L.M.T.B., J.B., C.M., E.J.K., E.T.W.); and Graduate School and University Center, City University of New York, New York, New York 10016 (R.F.Q., J.B., E.J.K., E.T.W.)
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20
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Shumskaya M, Bradbury LM, Monaco RR, Wurtzel ET. Plastid localization of the key carotenoid enzyme phytoene synthase is altered by isozyme, allelic variation, and activity. THE PLANT CELL 2012; 24:3725-41. [PMID: 23023170 PMCID: PMC3480298 DOI: 10.1105/tpc.112.104174] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 08/16/2012] [Accepted: 09/05/2012] [Indexed: 05/18/2023]
Abstract
Plant carotenoids have unique physiological roles related to specific plastid suborganellar locations. Carotenoid metabolic engineering could enhance plant adaptation to climate change and improve food security and nutritional value. However, lack of fundamental knowledge on carotenoid pathway localization limits targeted engineering. Phytoene synthase (PSY), a major rate-controlling carotenoid enzyme, is represented by multiple isozymes residing at unknown plastid sites. In maize (Zea mays), the three isozymes were transiently expressed and found either in plastoglobuli or in stroma and thylakoid membranes. PSY1, with one to two residue modifications of naturally occurring functional variants, exhibited altered localization, associated with distorted plastid shape and formation of a fibril phenotype. Mutating the active site of the enzyme reversed this phenotype. Discovery of differential PSY locations, linked with activity and isozyme type, advances the engineering potential for modifying carotenoid biosynthesis.
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Affiliation(s)
- Maria Shumskaya
- Department of Biological Sciences, Lehman College, City University of New York, Bronx, New York, 10468
| | - Louis M.T. Bradbury
- Department of Biological Sciences, Lehman College, City University of New York, Bronx, New York, 10468
| | - Regina R. Monaco
- Department of Biological Sciences, Lehman College, City University of New York, Bronx, New York, 10468
| | - Eleanore T. Wurtzel
- Department of Biological Sciences, Lehman College, City University of New York, Bronx, New York, 10468
- Graduate School and University Center, City University of New York, New York, New York 10016-4309
- Address correspondence to
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21
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Schaub P, Yu Q, Gemmecker S, Poussin-Courmontagne P, Mailliot J, McEwen AG, Ghisla S, Al-Babili S, Cavarelli J, Beyer P. On the structure and function of the phytoene desaturase CRTI from Pantoea ananatis, a membrane-peripheral and FAD-dependent oxidase/isomerase. PLoS One 2012; 7:e39550. [PMID: 22745782 PMCID: PMC3382138 DOI: 10.1371/journal.pone.0039550] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 05/22/2012] [Indexed: 11/19/2022] Open
Abstract
CRTI-type phytoene desaturases prevailing in bacteria and fungi can form lycopene directly from phytoene while plants employ two distinct desaturases and two cis-tans isomerases for the same purpose. This property renders CRTI a valuable gene to engineer provitamin A-formation to help combat vitamin A malnutrition, such as with Golden Rice. To understand the biochemical processes involved, recombinant CRTI was produced and obtained in homogeneous form that shows high enzymatic activity with the lipophilic substrate phytoene contained in phosphatidyl-choline (PC) liposome membranes. The first crystal structure of apo-CRTI reveals that CRTI belongs to the flavoprotein superfamily comprising protoporphyrinogen IX oxidoreductase and monoamine oxidase. CRTI is a membrane-peripheral oxidoreductase which utilizes FAD as the sole redox-active cofactor. Oxygen, replaceable by quinones in its absence, is needed as the terminal electron acceptor. FAD, besides its catalytic role also displays a structural function by enabling the formation of enzymatically active CRTI membrane associates. Under anaerobic conditions the enzyme can act as a carotene cis-trans isomerase. In silico-docking experiments yielded information on substrate binding sites, potential catalytic residues and is in favor of single half-site recognition of the symmetrical C(40) hydrocarbon substrate.
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Affiliation(s)
- Patrick Schaub
- Faculty of Biology, Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany
| | - Qiuju Yu
- Faculty of Biology, Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany
| | - Sandra Gemmecker
- Faculty of Biology, Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany
| | - Pierre Poussin-Courmontagne
- Département de Biologie Structurale Intégrative, Institut de Génétique et Biologie Moléculaire et Cellulaire, UDS, CNRS, INSERM, Illkirch, France
| | - Justine Mailliot
- Département de Biologie Structurale Intégrative, Institut de Génétique et Biologie Moléculaire et Cellulaire, UDS, CNRS, INSERM, Illkirch, France
| | - Alastair G. McEwen
- Département de Biologie Structurale Intégrative, Institut de Génétique et Biologie Moléculaire et Cellulaire, UDS, CNRS, INSERM, Illkirch, France
| | - Sandro Ghisla
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Salim Al-Babili
- Faculty of Biology, Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany
| | - Jean Cavarelli
- Département de Biologie Structurale Intégrative, Institut de Génétique et Biologie Moléculaire et Cellulaire, UDS, CNRS, INSERM, Illkirch, France
| | - Peter Beyer
- Faculty of Biology, Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany
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22
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Ruiz-Sola MÁ, Rodríguez-Concepción M. Carotenoid biosynthesis in Arabidopsis: a colorful pathway. THE ARABIDOPSIS BOOK 2012; 10:e0158. [PMID: 22582030 PMCID: PMC3350171 DOI: 10.1199/tab.0158] [Citation(s) in RCA: 322] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Plant carotenoids are a family of pigments that participate in light harvesting and are essential for photoprotection against excess light. Furthermore, they act as precursors for the production of apocarotenoid hormones such as abscisic acid and strigolactones. In this review, we summarize the current knowledge on the genes and enzymes of the carotenoid biosynthetic pathway (which is now almost completely elucidated) and on the regulation of carotenoid biosynthesis at both transcriptional and post-transcriptional levels. We also discuss the relevance of Arabidopsis as a model system for the study of carotenogenesis and how metabolic engineering approaches in this plant have taught important lessons for carotenoid biotechnology.
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Affiliation(s)
- M. Águila Ruiz-Sola
- Department of Molecular Genetics, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, 08193 Barcelona, Spain
| | - Manuel Rodríguez-Concepción
- Department of Molecular Genetics, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, 08193 Barcelona, Spain
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23
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Qin X, Coku A, Inoue K, Tian L. Expression, subcellular localization, and cis-regulatory structure of duplicated phytoene synthase genes in melon (Cucumis melo L.). PLANTA 2011; 234:737-48. [PMID: 21626149 DOI: 10.1007/s00425-011-1442-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Accepted: 05/14/2011] [Indexed: 05/20/2023]
Abstract
Carotenoids perform many critical functions in plants, animals, and humans. It is therefore important to understand carotenoid biosynthesis and its regulation in plants. Phytoene synthase (PSY) catalyzes the first committed and rate-limiting step in carotenoid biosynthesis. While PSY is present as a single copy gene in Arabidopsis, duplicated PSY genes have been identified in many economically important monocot and dicot crops. CmPSY1 was previously identified from melon (Cucumis melo L.), but was not functionally characterized. We isolated a second PSY gene, CmPSY2, from melon in this work. CmPSY2 possesses a unique intron/exon structure that has not been observed in other plant PSYs. Both CmPSY1 and CmPSY2 are functional in vitro, but exhibit distinct expression patterns in different melon tissues and during fruit development, suggesting differential regulation of the duplicated melon PSY genes. In vitro chloroplast import assays verified the plastidic localization of CmPSY1 and CmPSY2 despite the lack of an obvious plastid target peptide in CmPSY2. Promoter motif analysis of the duplicated melon and tomato PSY genes and the Arabidopsis PSY revealed distinctive cis-regulatory structures of melon PSYs and identified gibberellin-responsive motifs in all PSYs except for SlPSY1, which has not been reported previously. Overall, these data provide new insights into the evolutionary history of plant PSY genes and the regulation of PSY expression by developmental and environmental signals that may involve different regulatory networks.
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Affiliation(s)
- Xiaoqiong Qin
- Department of Plant Sciences, Mail Stop 3, University of California, Davis, Davis, CA, USA
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Poiroux-Gonord F, Bidel LPR, Fanciullino AL, Gautier H, Lauri-Lopez F, Urban L. Health benefits of vitamins and secondary metabolites of fruits and vegetables and prospects to increase their concentrations by agronomic approaches. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:12065-82. [PMID: 21067179 DOI: 10.1021/jf1037745] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Fruits and vegetables (FAVs) are an important part of the human diet and a major source of biologically active substances such as vitamins and secondary metabolites. The consumption of FAVs remains globally insufficient, so it should be encouraged, and it may be useful to propose to consumers FAVs with enhanced concentrations in vitamins and secondary metabolites. There are basically two ways to reach this target: the genetic approach or the environmental approach. This paper provides a comprehensive review of the results that have been obtained so far through purely agronomic approaches and brings them into perspective by comparing them with the achievements of genetic approaches. Although agronomic approaches offer very good perspectives, the existence of variability of responses suggests that the current understanding of the way regulatory and metabolic pathways are controlled needs to be increased. For this purpose, more in-depth study of the interactions existing between factors (light and temperature, for instance, genetic factors × environmental factors), between processes (primary metabolism and ontogeny, for example), and between organs (as there is some evidence that photooxidative stress in leaves affects antioxidant metabolism in fruits) is proposed.
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Affiliation(s)
- Florine Poiroux-Gonord
- INRA - Centre de Corse, Unité "Génétique et Ecophysiologie de la Qualité des Agrumes", F-20230 San Giuliano, France
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25
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Ahrazem O, Rubio-Moraga A, López RC, Gómez-Gómez L. The expression of a chromoplast-specific lycopene beta cyclase gene is involved in the high production of saffron's apocarotenoid precursors. JOURNAL OF EXPERIMENTAL BOTANY 2010; 61:105-19. [PMID: 19767307 DOI: 10.1093/jxb/erp283] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Crocus sativus is a triploid sterile plant characterized by its long red stigmas, which produce and store significant quantities of carotenoid derivatives formed from the oxidative cleavage of beta-carotene and zeaxanthin. The present study reports on the genomic structures of two lycopene-beta-cyclase genes, CstLcyB1 and CstLcyB2a, and on their transcription patterns in different C. sativus tissues. Phylogenetic analysis showed that both proteins are located in different groups: CstLcyB2a encodes chromoplast-specific lycopene cyclases, with an expression analysis showing strongly in flower stigmas where it activates and boosts beta-carotene accumulation. The CstLcyB1 transcript, however, was present in leaves, tepals, and stigmas at lower levels. In vivo assays in transgenic Arabidopsis demonstrated lycopene beta-cyclase activity of CstLcyB2a. CstLcyB2a is a CstLcyB1 paralogue derived through a gene duplication event, while promoter analysis showed that both genes have diverged in their regulatory sequences after duplication. Furthermore, it was found that the CstLcyB2a gene was absent from Crocus kotschyanus and, although present in C. goulimyi and C. cancellatus, the absence of transcripts suggests that transcriptional regulation of CstLcyB2a is responsible for the low apocarotenoid content in these species.
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Affiliation(s)
- Oussama Ahrazem
- Departamento de Ciencia y Tecnología Agroforestal y Genética, ETSIA, Universidad de Castilla-La Mancha, Campus Universitario s/n, E-02071 Albacete, Spain
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26
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Bonshtien AL, Parnas A, Sharkia R, Niv A, Mizrahi I, Azem A, Weiss C. Differential effects of co-chaperonin homologs on cpn60 oligomers. Cell Stress Chaperones 2009; 14:509-19. [PMID: 19224397 PMCID: PMC2728284 DOI: 10.1007/s12192-009-0104-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Revised: 01/29/2009] [Accepted: 02/01/2009] [Indexed: 01/13/2023] Open
Abstract
In this study, we have investigated the relationship between chaperonin/co-chaperonin binding, ATP hydrolysis, and protein refolding in heterologous chaperonin systems from bacteria, chloroplast, and mitochondria. We characterized two types of chloroplast cpn60 oligomers, ch-cpn60 composed of alpha and beta subunits (alpha(7)beta(7) ch-cpn60) and one composed of all beta subunits (beta(14) ch-cpn60). In terms of ATPase activity, the rate of ATP hydrolysis increased with protein concentration up to 60 microM, reflecting a concentration at which the oligomers are stable. At high concentrations of cpn60, all cpn10 homologs inhibited ATPase activity of alpha(7)beta(7) ch-cpn60. In contrast, ATPase of beta(14) ch-cpn60 was inhibited only by mitochondrial cpn10, supporting previous reports showing that beta(14) is functional only with mitochondrial cpn10 and not with other cpn10 homologs. Surprisingly, direct binding assays showed that both ch-cpn60 oligomer types bind to bacterial, mitochondrial, and chloroplast cpn10 homologs with an equal apparent affinity. Moreover, mitochondrial cpn60 binds chloroplast cpn20 with which it is not able to refold denatured proteins. Protein refolding experiments showed that in such instances, the bound protein is released in a conformation that is not able to refold. The presence of glycerol, or subsequent addition of mitochondrial cpn10, allows us to recover enzymatic activity of the substrate protein. Thus, in our systems, the formation of co-chaperonin/chaperonin complexes does not necessarily lead to protein folding. By using heterologous oligomer systems, we are able to separate the functions of binding and refolding in order to better understand the chaperonin mechanism.
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Affiliation(s)
- Anat L. Bonshtien
- Department of Biochemistry, The George Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, 69778 Israel
| | - Avital Parnas
- Department of Biochemistry, The George Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, 69778 Israel
| | - Rajach Sharkia
- Beit-Berl College, Beit-Berl, 44905 Israel
- The Triangle Research and Development Center, P.O. Box 2167, Kfar Qari’, 30075 Israel
| | - Adina Niv
- Department of Biochemistry, The George Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, 69778 Israel
| | - Itzhak Mizrahi
- Department of Biochemistry, The George Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, 69778 Israel
| | - Abdussalam Azem
- Department of Biochemistry, The George Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, 69778 Israel
| | - Celeste Weiss
- Department of Biochemistry, The George Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, 69778 Israel
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Maass D, Arango J, Wüst F, Beyer P, Welsch R. Carotenoid crystal formation in Arabidopsis and carrot roots caused by increased phytoene synthase protein levels. PLoS One 2009; 4:e6373. [PMID: 19636414 PMCID: PMC2712097 DOI: 10.1371/journal.pone.0006373] [Citation(s) in RCA: 160] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Accepted: 06/23/2009] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND As the first pathway-specific enzyme in carotenoid biosynthesis, phytoene synthase (PSY) is a prime regulatory target. This includes a number of biotechnological approaches that have successfully increased the carotenoid content in agronomically relevant non-green plant tissues through tissue-specific PSY overexpression. We investigated the differential effects of constitutive AtPSY overexpression in green and non-green cells of transgenic Arabidopsis lines. This revealed striking similarities to the situation found in orange carrot roots with respect to carotenoid amounts and sequestration mechanism. METHODOLOGY/PRINCIPAL FINDINGS In Arabidopsis seedlings, carotenoid content remained unaffected by increased AtPSY levels although the protein was almost quantitatively imported into plastids, as shown by western blot analyses. In contrast, non-photosynthetic calli and roots overexpressing AtPSY accumulated carotenoids 10 and 100-fold above the corresponding wild-type tissues and contained 1800 and 500 microg carotenoids per g dry weight, respectively. This increase coincided with a change of the pattern of accumulated carotenoids, as xanthophylls decreased relative to beta-carotene and carotene intermediates accumulated. As shown by polarization microscopy, carotenoids were found deposited in crystals, similar to crystalline-type chromoplasts of non-green tissues present in several other taxa. In fact, orange-colored carrots showed a similar situation with increased PSY protein as well as carotenoid levels and accumulation patterns whereas wild white-rooted carrots were similar to Arabidopsis wild type roots in this respect. Initiation of carotenoid crystal formation by increased PSY protein amounts was further confirmed by overexpressing crtB, a bacterial PSY gene, in white carrots, resulting in increased carotenoid amounts deposited in crystals. CONCLUSIONS The sequestration of carotenoids into crystals can be driven by the functional overexpression of one biosynthetic enzyme in non-green plastids not requiring a chromoplast developmental program as this does not exist in Arabidopsis. Thus, PSY expression plays a major, rate-limiting role in the transition from white to orange-colored carrots.
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Affiliation(s)
- Dirk Maass
- Faculty of Biology, Cell Biology, University of Freiburg, Freiburg, Germany
| | - Jacobo Arango
- Faculty of Biology, Cell Biology, University of Freiburg, Freiburg, Germany
| | - Florian Wüst
- Faculty of Biology, Cell Biology, University of Freiburg, Freiburg, Germany
| | - Peter Beyer
- Faculty of Biology, Cell Biology, University of Freiburg, Freiburg, Germany
| | - Ralf Welsch
- Faculty of Biology, Cell Biology, University of Freiburg, Freiburg, Germany
- * E-mail:
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Li F, Vallabhaneni R, Yu J, Rocheford T, Wurtzel ET. The maize phytoene synthase gene family: overlapping roles for carotenogenesis in endosperm, photomorphogenesis, and thermal stress tolerance. PLANT PHYSIOLOGY 2008; 147:1334-46. [PMID: 18508954 PMCID: PMC2442542 DOI: 10.1104/pp.108.122119] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Accepted: 05/20/2008] [Indexed: 05/19/2023]
Abstract
Carotenoids are essential for photosynthesis and photoprotection; they also serve as precursors to signaling molecules that influence plant development and biotic/abiotic stress responses. With potential to improve plant yield and nutritional quality, carotenoids are targets for metabolic breeding/engineering, particularly in the Poaceae (grass family), which includes the major food crops. Depending on genetic background, maize (Zea mays) endosperm carotenoid content varies, and therefore breeding-enhanced carotenoid levels have been of ongoing interest. The first committed step in the plastid-localized biosynthetic pathway is mediated by the nuclear-encoded phytoene synthase (PSY). The gene family in maize and other grasses contains three paralogs with specialized roles that are not well understood. Maize endosperm carotenoid accumulation requires PSY1 expression. A maize antibody was used to localize PSY1 to amyloplast envelope membranes and to determine PSY1 accumulation in relation to carotenoid accumulation in developing endosperm. To test when and if PSY transcript levels correlated with carotenoid content, advantage was taken of a maize germplasm diversity collection that exhibits genetic and chemical diversity. Total carotenoid content showed statistically significant correlation with endosperm transcript levels at 20 d after pollination for PSY1 but not PSY2 or PSY3. Timing of PSY1 transcript abundance, previously unknown, provides critical information for choosing breeding alleles or properly controlling introduced transgenes. PSY1 was unexpectedly found to have an additional role in photosynthetic tissue, where it was required for carotenogenesis in the dark and for heat stress tolerance. Leaf carotenogenesis was shown to require phytochrome-dependent and phytochrome-independent photoregulation of PSY2 plus nonphotoregulated PSY1 expression.
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Affiliation(s)
- Faqiang Li
- Department of Biological Sciences, Lehman College, The City University of New York, Bronx, New York 10468, USA
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Lopez AB, Yang Y, Thannhauser TW, Li L. Phytoene desaturase is present in a large protein complex in the plastid membrane. PHYSIOLOGIA PLANTARUM 2008; 133:190-198. [PMID: 18298413 DOI: 10.1111/j.1399-3054.2008.01058.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Phytoene desaturase (PDS; EC 1.14.99.-) represents one of the key enzymes in the carotenoid biosynthetic pathway and is present in nearly all types of plastids in plants. To further characterize PDS, we isolated the PDS cDNA from cauliflower (BoPDS) and confirmed its function by heterologous expression in a strain of Escherichia coli containing a carotenoid-producing plasmid. The BoPDS cDNA encodes a predicted mature protein of approximately 55 kDa. In comparison with PDS from a few other plant species, BoPDS exhibited a high enzyme activity in E. coli, and its expression in plastids was independent of carotenoid levels. Plastids were purified from tissues of different plant species including cauliflower curds, tomato fruits, carrot roots and Arabidopsis leaves. By employing both Blue Native PAGE and SDS-PAGE approaches in conjunction with Western blot analysis, it was found that PDS in these plants existed in two forms. The plastid membrane form was present in a large protein complex of approximately 350 kDa, whereas the stroma version was in an approximately 660 kDa complex.
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Affiliation(s)
- Alex B Lopez
- United States Department of Agriculture-Agriculture Research Service, Plant, Soil and Nutrition Laboratory, Cornell University, Ithaca, NY 14853, USA
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Welsch R, Wüst F, Bär C, Al-Babili S, Beyer P. A third phytoene synthase is devoted to abiotic stress-induced abscisic acid formation in rice and defines functional diversification of phytoene synthase genes. PLANT PHYSIOLOGY 2008; 147:367-80. [PMID: 18326788 PMCID: PMC2330301 DOI: 10.1104/pp.108.117028] [Citation(s) in RCA: 173] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Accepted: 03/03/2008] [Indexed: 05/18/2023]
Abstract
We here report on the characterization of a novel third phytoene synthase gene (PSY) in rice (Oryza sativa), OsPSY3, and on the differences among all three PSY genes with respect to the tissue-specific expression and regulation upon various environmental stimuli. The two already known PSYs are under phytochrome control and involved in carotenoid biosynthesis in photosynthetically active tissues and exhibit different expression patterns during chloroplast development. In contrast, OsPSY3 transcript levels are not affected by light and show almost no tissue-specific differences. Rather, OsPSY3 transcripts are up-regulated during increased abscisic acid (ABA) formation upon salt treatment and drought, especially in roots. The simultaneous induction of genes encoding 9-cis-epoxycarotenoid dioxygenases (NCEDs), involved in the initial steps of ABA biosynthesis, indicate that decreased xanthophyll levels are compensated by the induction of the third PSY gene. Furthermore, OsPSY3 and the OsNCEDs investigated were also induced by the application of ABA, indicating positive feedback regulation. The regulatory differences are mirrored by cis-acting elements in the corresponding promoter regions, with light-responsive elements for OsPSY1 and OsPSY2 and an ABA-response element as well as a coupling element for OsPSY3. The investigation of the gene structures and 5' untranslated regions revealed that OsPSY1 represents a descendant of an ancient PSY gene present in the common ancestor of monocots and dicots. Since the genomic structures of OsPSY2 and OsPSY3 are comparable, we conclude that they originated from the most recent common ancestor, OsPSY1.
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Affiliation(s)
- Ralf Welsch
- Faculty of Biology, Center for Applied Biosciences, University of Freiburg, 79104 Freiburg, Germany
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31
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Giorio G, Stigliani AL, D'Ambrosio C. Phytoene synthase genes in tomato (Solanumlycopersicum L.) - new data on the structures, the deduced amino acid sequences and the expression patterns. FEBS J 2007; 275:527-35. [PMID: 18167141 DOI: 10.1111/j.1742-4658.2007.06219.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The fruit of tomato (Solanum lycopersicum L.) is a berry: red, fleshy and rich in seeds. Its colour is due to the high content of lycopene whose synthesis is activated by the phytoene synthase 1 (PSY1) enzyme, encoded by Psy1 which is distinct from Psy2. In the present study, we report on the genomic structures of the Psy1 and Psy2 genes and on their transcription patterns in different tomato tissues. Our results have completely clarified the structure of the Psy1 and Psy2 genes in the coding sequence region. The two genes were shown to have an highly conserved structure, with seven exons being almost identical and six introns being much more variable. For Psy1 and Psy2, respectively, the sequenced regions were 4527 and 3542 bp long, the coding sequences were 1239 bp and 1317 bp long, whereas the predicted protein sequences were 412 and 438 amino acids. The two proteins are almost identical in the central region, whereas most differences are present in the N-terminus and C-terminus. Quantitative real time PCR analysis showed that Psy2 transcript was present in all tested plant tissues, whereas Psy1 transcript could be detected in chromoplast-containing tissues, particularly in fruit where it activates and boosts lycopene accumulation. Interestingly, the organ with the highest relative content of Psy2 transcript is the petal and not the leaf. Psy1 is a Psy2 paralog derived through a gene duplication event that have involved other genes encoding rate controlling enzymes of the carotenoid pathway. Duplicate genes have been recruited to allow carotenoid synthesis in petals and fruits. However, recruitment of carotenoid metabolism for fruit pigmentation could have occurred later in the evolution, either because phytoene synthase gene duplication occurred later or because the fruit pigmentation process required a more sophisticated mechanism involving tight control of the transcription of other genes.
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Kloer DP, Welsch R, Beyer P, Schulz GE. Structure and Reaction Geometry of Geranylgeranyl Diphosphate Synthase from Sinapis alba,. Biochemistry 2006; 45:15197-204. [PMID: 17176041 DOI: 10.1021/bi061572k] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The crystal structure of the geranylgeranyl diphosphate synthase from Sinapis alba (mustard) has been solved in two crystal forms at 1.8 and 2.0 A resolutions. In one of these forms, the dimeric enzyme binds one molecule of the final product geranylgeranyl diphosphate in one subunit. The chainfold of the enzyme corresponds to that of other members of the farnesyl diphosphate synthase family. Whereas the binding modes of the two substrates dimethylallyl diphosphate and isopentenyl diphosphate at the allyl and isopentenyl sites, respectively, have been established with other members of the family, the complex structure presented reveals for the first time the binding mode of a reaction product at the isopentenyl site. The binding geometry of substrates and product in conjunction with the protein environment and the established chemistry of the reaction provide a clear picture of the reaction steps and atom displacements. Moreover, a comparison with a ligated homologous structure outlined an appreciable induced fit: helix alpha8 and its environment undergo a large conformational change when either the substrate dimethylallyl diphosphate or an analogue is bound to the allyl site; only a minor conformational change occurs when the other substrate isopentenyl diphosphate or the product is bound to the isopentenyl site.
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Affiliation(s)
- Daniel P Kloer
- Institut für Organische Chemie und Biochemie, Albert-Ludwigs-Universität, Albertstrasse 21, D-79104 Freiburg im Breisgau, Germany
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Arias RS, Dayan FE, Michel A, Howell J, Scheffler BE. Characterization of a higher plant herbicide-resistant phytoene desaturase and its use as a selectable marker. PLANT BIOTECHNOLOGY JOURNAL 2006; 4:263-73. [PMID: 17177802 DOI: 10.1111/j.1467-7652.2006.00179.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Three natural somatic mutations at codon 304 of the phytoene desaturase gene (pds) of Hydrilla verticillata (L. f. Royle) have been reported to provide resistance to the herbicide fluridone. We substituted the arginine 304 present in the wild-type H. verticillata phytoene desaturase (PDS) with all 19 other natural amino acids and tested PDS against fluridone. In in vitro assays, the threonine (Thr), cysteine (Cys), alanine (Ala) and glutamine (Gln) mutations imparted the highest resistance to fluridone. Thr, the three natural mutations [Cys, serine (Ser), histidine (His)] and the wild-type PDS protein were tested in vitro against seven inhibitors of PDS representing several classes of herbicides. These mutations conferred cross-resistance to norflurazon and overall negative cross-resistance to beflubutamid, picolinafen and diflufenican. The T3 generation of transgenic Arabidopsis thaliana plants harbouring the four selected mutations and wild-type pds had similar patterns of cross-resistance to the herbicides as observed in the in vitro assays. The Thr304 Hydrilla pds mutant proved to be an excellent marker for the selection of transgenic plants. Seedlings harbouring Thr304 pds had a maximum resistance to sensitivity (R/S) ratio of 57 and 14 times higher than that of the wild-type for treatments with norflurazon and fluridone, respectively. These plants exhibited normal growth and development, even after long-term exposure to herbicide. As Thr304 pds is of plant origin, it could become more acceptable than other selectable markers for use in genetically modified food.
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Affiliation(s)
- Renée S Arias
- USDA-ARS, Natural Products Utilization Research Unit, PO Box 8048, University, MS 38677, USA
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Hirooka K, Izumi Y, An CI, Nakazawa Y, Fukusaki EI, Kobayashi A. Functional analysis of two solanesyl diphosphate synthases from Arabidopsis thaliana. Biosci Biotechnol Biochem 2005; 69:592-601. [PMID: 15784989 DOI: 10.1271/bbb.69.592] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Solanesyl diphosphate (SPP) is regarded as the precursor of the side-chains of both plastoquinone and ubiquinone in Arabidopsis thaliana. We previously analyzed A. thaliana SPP synthase (At-SPS1) (Hirooka et al., Biochem. J., 370, 679-686 (2003)). In this study, we cloned a second SPP synthase (At-SPS2) gene from A. thaliana and characterized the recombinant protein. Kinetic analysis indicated that At-SPS2 prefers geranylgeranyl diphosphate to farnesyl diphosphate as the allylic substrate. Several of its features, including the substrate preference, were similar to those of At-SPS1. These data indicate that At-SPS1 and At-SPS2 share their basic catalytic machinery. Moreover, analysis of the subcellular localization by the transient expression of green fluorescent protein-fusion proteins showed that At-SPS2 is transported into chloroplasts, whereas At-SPS1 is likely to be localized in the endoplasmic reticulum in the A. thaliana cells. It is known that the ubiquinone side-chain originates from isopentenyl diphosphate derived from the cytosolic mevalonate pathway, while the plastoquinone side-chain is synthesized from isopentenyl diphosphate derived from the plastidial methylerythritol phosphate pathway. Based on this information, we propose that At-SPS1 contributes to the biosynthesis of the ubiquinone side-chain and that At-SPS2 supplies the precursor of the plastoquinone side-chain in A. thaliana.
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Affiliation(s)
- Kazutake Hirooka
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Yamadaoka, Japan
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Abstract
This review focuses on the biosynthesis of pigments in the unicellular alga Chlamydomonas reinhardtii and their physiological and regulatory functions in the context of information gathered from studies of other photosynthetic organisms. C. reinhardtii is serving as an important model organism for studies of photosynthesis and the pigments associated with the photosynthetic apparatus. Despite extensive information pertaining to the biosynthetic pathways critical for making chlorophylls and carotenoids, we are just beginning to understand the control of these pathways, the coordination between pigment and apoprotein synthesis, and the interactions between the activities of these pathways and those for other important cellular metabolites branching from these pathways. Other exciting areas relating to pigment function are also emerging: the role of intermediates of pigment biosynthesis as messengers that coordinate metabolism in the chloroplast with nuclear gene activity, and the identification of photoreceptors and their participation in critical cellular processes including phototaxis, gametogenesis, and the biogenesis of the photosynthetic machinery. These areas of research have become especially attractive for intensive development with the application of potent molecular and genomic tools currently being applied to studies of C. reinhardtii.
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Affiliation(s)
- Arthur R Grossman
- The Carnegie Institution of Washington, Department of Plant Biology, Stanford, California 94305, USA.
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36
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Arias RS, Netherland MD, Scheffler BE, Puri A, Dayan FE. Molecular evolution of herbicide resistance to phytoene desaturase inhibitors in Hydrilla verticillata and its potential use to generate herbicide-resistant crops. PEST MANAGEMENT SCIENCE 2005; 61:258-268. [PMID: 15668922 DOI: 10.1002/ps.1022] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Hydrilla [Hydrilla verticillata (Lf) Royle] is one of the most serious invasive aquatic weed problems in the USA. This plant possesses numerous mechanisms of vegetative reproduction that enable it to spread very rapidly. Management of this weed has been achieved by the systemic treatment of water bodies with the herbicide fluridone. At least three dioecious fluridone-resistant biotypes of hydrilla with two- to fivefold higher resistance to the herbicide than the wild-type have been identified. Resistance is the result of one of three independent somatic mutations at the arginine 304 codon of the gene encoding phytoene desaturase, the molecular target site of fluridone. The specific activities of the three purified phytoene desaturase variants are similar to the wild-type enzyme. The appearance of these herbicide-resistant biotypes may jeopardize the ability to control the spread of this non-indigenous species to other water bodies in the southern USA. The objective of this paper is to provide general information about the biology and physiology of this aquatic weed in relation to its recent development of resistance to the herbicide fluridone, and to discuss how this discovery might lead to a new generation of herbicide-resistant crops.
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Affiliation(s)
- Renée S Arias
- USDA/ARS, Natural Products Utilization Research Unit, PO Box 8048, University, Mississippi 38677, USA
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Ravanello MP, Ke D, Alvarez J, Huang B, Shewmaker CK. Coordinate expression of multiple bacterial carotenoid genes in canola leading to altered carotenoid production. Metab Eng 2004; 5:255-63. [PMID: 14642353 DOI: 10.1016/j.ymben.2003.08.001] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Carotenoids have drawn much attention recently because of their potentially positive benefits to human health as well as their utility in both food and animal feed. Previous work in canola (Brassica napus) seed over-expressing the bacterial phytoene synthase gene (crtB) demonstrated a change in carotenoid content, such that the total levels of carotenoids, including phytoene and downstream metabolites like beta-carotene, were elevated 50-fold, with the ratio of beta- to alpha-carotene being 2:1. This result raised the possibility that the composition of metabolites in this pathway could be modified further in conjunction with the increased flux obtained with crtB. Here we report on the expression of additional bacterial genes for the enzymes geranylgeranyl diphosphate synthase (crtE), phytoene desaturase (crtI) and lycopene cyclase (crtY and the plant B. napus lycopene beta-cyclase) engineered in conjunction with phytoene synthase (crtB) in transgenic canola seed. Analysis of the carotenoid levels by HPLC revealed a 90% decrease in phytoene levels for the double construct expressing crtB in conjunction with crtI. The transgenic seed from all the double constructs, including the one expressing the bacterial crtB and the plant lycopene beta-cyclase showed an increase in the levels of total carotenoid similar to that previously observed by expressing crtB alone but minimal effects were observed with respect to the ratio of beta- to alpha-carotene compared to the original construct. However, the beta- to alpha-carotene ratio was increased from 2:1 to 3:1 when a triple construct consisting of the bacterial phytoene synthase, phytoene desaturase and lycopene cyclase genes were expressed together. This result suggests that the bacterial genes may form an aggregate complex that allows in vivo activity of all three proteins through substrate channeling. This finding should allow further manipulation of the carotenoid biosynthetic pathway for downstream products with enhanced agronomic, animal feed and human nutritional values.
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Naested H, Holm A, Jenkins T, Nielsen HB, Harris CA, Beale MH, Andersen M, Mant A, Scheller H, Camara B, Mattsson O, Mundy J. Arabidopsis VARIEGATED 3 encodes a chloroplast-targeted, zinc-finger protein required for chloroplast and palisade cell development. J Cell Sci 2004; 117:4807-18. [PMID: 15340011 DOI: 10.1242/jcs.01360] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The stable, recessive Arabidopsis variegated 3 (var3) mutant exhibits a variegated phenotype due to somatic areas lacking or containing developmentally retarded chloroplasts and greatly reduced numbers of palisade cells. The VAR3 gene, isolated by transposon tagging, encodes the 85.9 kDa VAR3 protein containing novel repeats and zinc fingers described as protein interaction domains. VAR3 interacts specifically in yeast and in vitro with NCED4, a putative polyene chain or carotenoid dioxygenase, and both VAR3 and NCED4 accumulate in the chloroplast stroma. Metabolic profiling demonstrates that pigment profiles are qualitatively similar in wild type and var3, although var3 accumulates lower levels of chlorophylls and carotenoids. These results indicate that VAR3 is a part of a protein complex required for normal chloroplast and palisade cell development.
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Affiliation(s)
- Henrik Naested
- Institute of Molecular Biology, Copenhagen University, Øster Farimagsgade 2A, 1353 Copenhagen K, Denmark
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Chapter five Genomics, genetics, and biochemistry of maize carotenoid biosynthesis. SECONDARY METABOLISM IN MODEL SYSTEMS 2004. [DOI: 10.1016/s0079-9920(04)80006-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Kleine T, Lockhart P, Batschauer A. An Arabidopsis protein closely related to Synechocystis cryptochrome is targeted to organelles. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2003; 35:93-103. [PMID: 12834405 DOI: 10.1046/j.1365-313x.2003.01787.x] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Cryptochromes (CRYs) are blue/UV-A photoreceptors related to the DNA repair enzyme DNA photolyase. They have been found in plants, animals and most recently in the cyanobacterium Synechocystis. Closely related to the Synechocystis cryptochrome is the Arabidopsis gene At5g24850. Here, we show that the encoded protein of At5g24850 binds flavin adenine dinucleotide (FAD). It has no photolyase activity, and is likely to function as a photoreceptor. We have named it At-cry3 to distinguish it from the other Arbabidopsis cryptochrome homologues At-cry1 and At-cry2. At-cry3 carries an N-terminal sequence, which mediates import into chloroplasts and mitochondria. Furthermore, we show that At-cry3 binds DNA. DNA binding was also demonstrated for the Synechocystis cryptochrome, indicating that both photoreceptors could have similar modes of action. Based on the finding of a new cryptochrome class in bacteria and plants, it has been suggested that cryptochromes evolved before the divergence of eukaryotes and prokaryotes. However, our phylogenetic analyses are also consistent with an alternative explanation that the presence of cryptochromes in the plant nuclear genome is the result of dual horizontal gene transfer. That is, CRY1 and CRY2 genes may originate from an endosymbiotic ancestor of modern-day alpha-proteobacteria, while the CRY3 gene may originate from an endosymbiotic ancestor of modern-day cyanobacteria.
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Affiliation(s)
- Tatjana Kleine
- FB Biologie/Pflanzenphysiologie, Philipps-Universität, Karl-von-Frisch-Str. 8, 35032 Marburg, Germany
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Hirooka K, Bamba T, Fukusaki EI, Kobayashi A. Cloning and kinetic characterization of Arabidopsis thaliana solanesyl diphosphate synthase. Biochem J 2003; 370:679-86. [PMID: 12437513 PMCID: PMC1223189 DOI: 10.1042/bj20021311] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2002] [Revised: 11/12/2002] [Accepted: 11/19/2002] [Indexed: 11/17/2022]
Abstract
trans -Long-chain prenyl diphosphate synthases catalyse the sequential condensation of isopentenyl diphosphate (C(5)) units with allylic diphosphate to produce the C(30)-C(50) prenyl diphosphates, which are precursors of the side chains of prenylquinones. Based on the relationship between product specificity and the region around the first aspartate-rich motif in trans -prenyl diphosphate synthases characterized so far, we have isolated the cDNA for a member of trans -long-chain prenyl diphosphate synthases from Arabidopsis thaliana. The cDNA was heterologously expressed in Escherichia coli, and the recombinant His(6)-tagged protein was purified and characterized. Product analysis revealed that the cDNA encodes solanesyl diphosphate (C(45)) synthase (At-SPS). At-SPS utilized farnesyl diphosphate (FPP; C(15)) and geranylgeranyl diphosphate (GGPP; C(20)), but did not accept either the C(5) or the C(10) allylic diphosphate as a primer substrate. The Michaelis constants for FPP and GGPP were 5.73 microM and 1.61 microM respectively. We also performed an analysis of the side chains of prenylquinones extracted from the A. thaliana plant, and showed that its major prenylquinones, i.e. plastoquinone and ubiquinone, contain the C(45) prenyl moiety. This suggests that At-SPS might be devoted to the biosynthesis of either or both of the prenylquinone side chains. This is the first established trans -long-chain prenyl diphosphate synthase from a multicellular organism.
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Affiliation(s)
- Kazutake Hirooka
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita Yamadaoka 2-1, Osaka 565-0871, Japan
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Beyer P, Al-Babili S, Ye X, Lucca P, Schaub P, Welsch R, Potrykus I. Golden Rice: introducing the beta-carotene biosynthesis pathway into rice endosperm by genetic engineering to defeat vitamin A deficiency. J Nutr 2002; 132:506S-510S. [PMID: 11880581 DOI: 10.1093/jn/132.3.506s] [Citation(s) in RCA: 274] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
To obtain a functioning provitamin A (beta-carotene) biosynthetic pathway in rice endosperm, we introduced in a single, combined transformation effort the cDNA coding for phytoene synthase (psy) and lycopene beta-cyclase (beta-lcy) both from Narcissus pseudonarcissus and both under the control of the endosperm-specific glutelin promoter together with a bacterial phytoene desaturase (crtI, from Erwinia uredovora under constitutive 35S promoter control). This combination covers the requirements for beta-carotene synthesis and, as hoped, yellow beta-carotene-bearing rice endosperm was obtained in the T(0)-generation. Additional experiments revealed that the presence of beta-lcy was not necessary, because psy and crtI alone were able to drive beta-carotene synthesis as well as the formation of further downstream xanthophylls. Plausible explanations for this finding are that these downstream enzymes are constitutively expressed in rice endosperm or are induced by the transformation, e.g., by enzymatically formed products. Results using N. pseudonarcissus as a model system led to the development of a hypothesis, our present working model, that trans-lycopene or a trans-lycopene derivative acts as an inductor in a kind of feedback mechanism stimulating endogenous carotenogenic genes. Various institutional arrangements for disseminating Golden Rice to research institutes in developing countries also are discussed.
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Affiliation(s)
- Peter Beyer
- University of Freiburg, Center for Applied Biosciences, D-79104 Freiburg, Germany.
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Busch M, Seuter A, Hain R. Functional analysis of the early steps of carotenoid biosynthesis in tobacco. PLANT PHYSIOLOGY 2002; 128:439-53. [PMID: 11842148 PMCID: PMC148907 DOI: 10.1104/pp.010573] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2001] [Revised: 08/29/2001] [Accepted: 10/18/2001] [Indexed: 05/18/2023]
Abstract
Carotenoids contribute to energy transduction in the light harvesting complexes and serve in protection from excess light fluence. Because of the importance of carotenoids, the genes encoding enzymes of carotenoid biosynthesis in higher plants are potential targets for herbicides. To obtain further insight into tobacco carotenoid biosynthesis and to investigate and prioritize potential herbicide targets in the pathway, the effects of changed phytoene synthase (PSY) and phytoene desaturase (PDS) gene expression were studied in transgenic tobacco (Nicotiana tabacum Petit Havana SR1) plants. Genes for both enzymes were cloned from tobacco, and surprisingly two functional PSY genes were found. Transgenic tobacco plants constitutively expressing these genes in both sense and antisense orientations were examined regarding phenotype, carotenoid content and transcript levels of carotene biosynthesis genes. Overexpression of either psy gene resulted in severe phenotypic effects including dwarfism, altered leaf morphology, and pigmentation. A correlation among phenotype, transcript level, and metabolic profile was demonstrated by comparison of hemizygous and homozygous plants from the same transformation event. Antisense expression of PSY and PDS also caused lethal phenotypes. Transcript levels of other carotene biosynthesis genes remained unaltered in the transgenic mutant. Phytoene accumulated in plants expressing antisense RNA to pds. However, elevated levels of phytoene were detected suggesting an increase in metabolic flux into this pathway.
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Affiliation(s)
- Marco Busch
- Bayer AG, Agricultural Division Research, Molecular Target Research and Biotechnology, 51368 Leverkusen, Germany
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al-Babili S, Ye X, Lucca P, Potrykus I, Beyer P. Biosynthesis of beta-carotene (provitamin A) in rice endosperm achieved by genetic engineering. NOVARTIS FOUNDATION SYMPOSIUM 2002; 236:219-28; discussion 228-32. [PMID: 11387982 DOI: 10.1002/9780470515778.ch16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
To obtain a functioning provitamin A (beta-carotene) biosynthetic pathway in rice endosperm, we introduced in a single, combined transformation effort the cDNAs coding for (1) phytoene synthase (psy) and (2) lycopene beta-cyclase (beta-lcy; both from Narcissus pseudonarcissus and both under control of the endosperm-specific glutelin promoter), with (3) a bacterial phytoene desaturase (crtI, from Erwinia uredovora under constitutive 35S promoter control). This combination covers the requirements for beta-carotene synthesis, and yellow, beta-carotene-bearing rice endosperm was obtained in the T0 generation. However, further experiments revealed that the presence of beta-lcy was not necessary, since psy and crtI alone were able to drive beta-carotene synthesis as well as the formation of further downstream xanthophylls. This finding could be explained if these downstream enzymes are either constitutively expressed in rice endosperm or are induced by the transformation, e.g. by products derived therefrom. Based on results in N. pseudonarcissus as a model system, a likely hypothesis can be developed that trans lycopene or a trans lycopene derivative acts as an inductor in a kind of feedback mechanism stimulating endogenous carotenogenic genes.
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Affiliation(s)
- S al-Babili
- University of Freiburg, Center for Applied Biosciences, D-79104 Freiburg, Germany
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Tan BC, Cline K, McCarty DR. Localization and targeting of the VP14 epoxy-carotenoid dioxygenase to chloroplast membranes. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2001; 27:373-82. [PMID: 11576422 DOI: 10.1046/j.1365-313x.2001.01102.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Abscisic acid (ABA) is a key regulator of seed dormancy and plant responses to environmental challenges. ABA is synthesized via an oxidative cleavage of 9-cis epoxy-carotenoids, the first committed and key regulatory step in the ABA biosynthetic pathway. Vp14 of maize encodes an epoxy-carotenoid dioxygenase that is soluble when expressed in E. coli. An important goal has been to determine how the soluble VP14 protein is targeted to epoxy-carotenoid substrates that are located in the thylakoid and envelope membranes of chloroplasts and other plastids. Using an in vitro chloroplast import assay, we have shown that VP14 is imported into chloroplasts with cleavage of a short stroma-targeting domain. The mature VP14 exists in two forms, one which is soluble in stroma and the other bound to thylakoid membranes. Analysis of a series of truncated VP14 mutants mapped the membrane targeting signal to the 160 amino acid N-terminal sequence. A putative amphipathic alpha-helix within this region is essential, but not sufficient, for the membrane targeting. Either deletion of or insertion of helix breaking residues into this region abolished the membrane binding, whereas a chimeric protein carrying just the amphipathic region fused with bacterial glutathione S-transferase failed to associate with the thylakoid membrane. The membrane-bound VP14 was partially resistant to chaotropic washes such as 0.1 M Na2CO3 (pH 11.5) and 6 M urea. Unlabelled recombinant VP14 inhibited the tight binding of imported VP14, suggesting that VP14 is associated with specific components of the thylakoid membrane.
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Affiliation(s)
- B C Tan
- Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL 32611, USA
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Al-Babili S, Hugueney P, Schledz M, Welsch R, Frohnmeyer H, Laule O, Beyer P. Identification of a novel gene coding for neoxanthin synthase from Solanum tuberosum. FEBS Lett 2000; 485:168-72. [PMID: 11094161 DOI: 10.1016/s0014-5793(00)02193-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The polymerase chain reaction analysis of potato plants, transformed with capsanthin capsorubin synthase ccs, revealed the presence of a highly related gene. The cloned cDNA showed at the protein level 89.6% identity to CCS. This suggested that the novel enzyme catalyzes a mechanistically similar reaction. Such a reaction is represented by neoxanthin synthase (NXS), forming the xanthophyll neoxanthin, a direct substrate for abscisic acid formation. The function of the novel enzyme could be proven by transient expression in plant protoplasts and high performance liquid chromatography analysis. The cloned NXS was imported in vitro into plastids, the compartment of carotenoid biosynthesis.
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Affiliation(s)
- S Al-Babili
- Center for Applied Biosciences, University of Freiburg, Germany
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Pogson BJ, Rissler HM. Genetic manipulation of carotenoid biosynthesis and photoprotection. Philos Trans R Soc Lond B Biol Sci 2000; 355:1395-403. [PMID: 11127994 PMCID: PMC1692877 DOI: 10.1098/rstb.2000.0701] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
There are multiple complementary and redundant mechanisms to provide protection against photo-oxidative damage, including non-photochemical quenching (NPQ). NPQ dissipates excess excitation energy as heat by using xanthophylls in combination with changes to the light-harvesting complex (LHC) antenna. The xanthophylls are oxygenated carotenoids that in addition to contributing to NPQ can quench singlet or triplet chlorophyll and are necessary for the assembly and stability of the antenna. We have genetically manipulated the expression of the epsilon-cyclase and beta-carotene hydroxylase carotenoid biosynthetic enzymes in Arabidopsis thaliana. The epsilon-cyclase overexpression confirmed that lut2 (lutein deficient) is a mutation in the epsilon-cyclase gene and demonstrated that lutein content can be altered at the level of mRNA abundance with levels ranging from 0 to 180% of wild-type. Also, it is clear that lutein affects the induction and extent of NPQ. The deleterious effects of lutein deficiency on NPQ in Arabidopsis and Chlamydomonas are additive, no matter what the genetic background, whether npq1 (zeaxanthin deficient), aba1 or antisense beta-hydroxylase (xanthophyll cycle pool decreased). Additionally, increasing lutein content causes a marginal, but significant, increase in the rate of induction of NPQ despite a reduction in the xanthophyll cycle pool size.
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Affiliation(s)
- B J Pogson
- Division of Biochemistry and Molecular Biology, The Australian National University, Canberra, ACT.
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Mann V, Harker M, Pecker I, Hirschberg J. Metabolic engineering of astaxanthin production in tobacco flowers. Nat Biotechnol 2000; 18:888-92. [PMID: 10932161 DOI: 10.1038/78515] [Citation(s) in RCA: 187] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Using metabolic engineering, we have modified the carotenoid biosynthesis pathway in tobacco (Nicotiana tabacum) to produce astaxanthin, a red pigment of considerable economic value. To alter the carotenoid pathway in chromoplasts of higher plants, the cDNA of the gene CrtO from the alga Haematococcus pluvialis, encoding beta-carotene ketolase, was transferred to tobacco under the regulation of the tomato Pds (phytoene desaturase) promoter. The transit peptide of PDS from tomato was used to target the CRTO polypeptide to the plastids. Chromoplasts in the nectary tissue of transgenic plants accumulated (3S,3'S) astaxanthin and other ketocarotenoids, changing the color of the nectary from yellow to red. This accomplishment demonstrates that plants can be used as a source of novel carotenoid pigments such as astaxanthin. The procedures described in this work can serve as a platform technology for future genetic manipulations of pigmentation of fruits and flowers of horticultural and floricultural importance.
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Affiliation(s)
- V Mann
- Department of Genetics, The Life Sciences Institute, The Hebrew University of Jerusalem, Israel
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Abstract
Complex plastids, found in many alga groups, are surrounded by three or four membranes. Therefore, proteins of the complex plastids, which are encoded in the cell nucleus, must cross three or four membranes during transport to the plastid. To study this process we have developed a method for isolating transport-competent two membrane-bound plastids derived from the complex plastids of the cryptophyte Guillardia theta. This in vitro protein import system provides the first non-heterologous system for studying the import of proteins into four-membrane complex plastids. We use our import system as well as canine microsomes to demonstrate in the case of cryptomonads how nuclear proteins pass the first nucleomorph-encoded proteins the third and fourth membrane and discuss the potential mechanisms for protein transport across the second membrane.
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Affiliation(s)
- J Wastl
- Department of Cell Biology and Applied Botany, Philipps-University Marburg, Karl-von-Frisch-Strasse, D-35032 Marburg, Germany
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Grünewald K, Eckert M, Hirschberg J, Hagen C. Phytoene desaturase is localized exclusively in the chloroplast and up-regulated at the mRNA level during accumulation of secondary carotenoids in Haematococcus pluvialis (Volvocales, chlorophyceae). PLANT PHYSIOLOGY 2000; 122:1261-8. [PMID: 10759523 PMCID: PMC58962 DOI: 10.1104/pp.122.4.1261] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/1999] [Accepted: 12/27/1999] [Indexed: 05/18/2023]
Abstract
The unicellular green alga Haematococcus pluvialis Flotow is known for its massive accumulation of ketocarotenoids under various stress conditions. Therefore, this microalga is one of the favored organisms for biotechnological production of these antioxidative compounds. Astaxanthin makes up the main part of the secondary carotenoids and is accumulated mostly in an esterified form in extraplastidic lipid vesicles. We have studied phytoene desaturase, an early enzyme of the carotenoid biosynthetic pathway. The increase in the phytoene desaturase protein levels that occurs following induction is accompanied by a corresponding increase of its mRNA during the accumulation period, indicating that phytoene desaturase is regulated at the mRNA level. We also investigated the localization of the enzyme by western-blot analysis of cell fractions and by immunogold labeling of ultrathin sections for electron microscopy. In spite of the fact that secondary carotenoids accumulate outside the chloroplast, no extra pathway specific for secondary carotenoid biosynthesis in H. pluvialis was found, at least at this early stage in the biosynthesis. A transport process of carotenoids from the site of biosynthesis (chloroplast) to the site of accumulation (cytoplasmatic located lipid vesicles) is implicated.
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Affiliation(s)
- K Grünewald
- Institute of General Botany, Friedrich-Schiller-University Jena, Am Planetarium 1, D-07743 Jena, Germany.
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