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Fan T, Roling L, Hedtke B, Grimm B. FC2 stabilizes POR and suppresses ALA formation in the tetrapyrrole biosynthesis pathway. THE NEW PHYTOLOGIST 2023; 239:624-638. [PMID: 37161708 DOI: 10.1111/nph.18952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 04/08/2023] [Indexed: 05/11/2023]
Abstract
During photoperiodic growth, the light-dependent nature of chlorophyll synthesis in angiosperms necessitates robust control of the production of 5-aminolevulinic acid (ALA), the rate-limiting step in the initial stage of tetrapyrrole biosynthesis (TBS). We are interested in dissecting the post-translational control of this process, which suppresses ALA synthesis for chlorophyll synthesis in dark-grown plants. Using biochemical approaches for analysis of Arabidopsis wild-type (WT) and mutant lines as well as complementation lines, we show that the heme-synthesizing ferrochelatase 2 (FC2) interacts with protochlorophyllide oxidoreductase and the regulator FLU which both promote the feedback-controlled suppression of ALA synthesis by inactivation of glutamyl-tRNA reductase, thus preventing excessive accumulation of potentially deleterious tetrapyrrole intermediates. Thereby, FC2 stabilizes POR by physical interaction. When the interaction between FC2 and POR is perturbed, suppression of ALA synthesis is attenuated and photoreactive protochlorophyllide accumulates. FC2 is anchored in the thylakoid membrane via its membrane-spanning CAB (chlorophyll-a-binding) domain. FC2 is one of the two isoforms of ferrochelatase catalyzing the last step of heme synthesis. Although FC2 belongs to the heme-synthesizing branch of TBS, its interaction with POR potentiates the effects of the GluTR-inactivation complex on the chlorophyll-synthesizing branch and ensures reciprocal control of chlorophyll and heme synthesis.
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Affiliation(s)
- Tingting Fan
- Humboldt-Universität zu Berlin, Institute of Biology/Plant Physiology, Philippstraße 13, Building 12,, D-10115, Berlin, Germany
- College of Forestry, Central South University of Forestry and Technology, Changsha, Hunan, 410004, China
| | - Lena Roling
- Humboldt-Universität zu Berlin, Institute of Biology/Plant Physiology, Philippstraße 13, Building 12,, D-10115, Berlin, Germany
| | - Boris Hedtke
- Humboldt-Universität zu Berlin, Institute of Biology/Plant Physiology, Philippstraße 13, Building 12,, D-10115, Berlin, Germany
| | - Bernhard Grimm
- Humboldt-Universität zu Berlin, Institute of Biology/Plant Physiology, Philippstraße 13, Building 12,, D-10115, Berlin, Germany
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2
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Su X, Yue X, Kong M, Xie Z, Yan J, Ma W, Wang Y, Zhao J, Zhang X, Liu M. Leaf Color Classification and Expression Analysis of Photosynthesis-Related Genes in Inbred Lines of Chinese Cabbage Displaying Minor Variations in Dark-Green Leaves. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12112124. [PMID: 37299103 DOI: 10.3390/plants12112124] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 05/20/2023] [Accepted: 05/21/2023] [Indexed: 06/12/2023]
Abstract
The leaves of the Chinese cabbage which is most widely consumed come in a wide variety of colors. Leaves that are dark green can promote photosynthesis, effectively improving crop yield, and therefore hold important application and cultivation value. In this study, we selected nine inbred lines of Chinese cabbage displaying slight differences in leaf color, and graded the leaf color using the reflectance spectra. We clarified the differences in gene sequences and the protein structure of ferrochelatase 2 (BrFC2) among the nine inbred lines, and used qRT-PCR to analyze the expression differences of photosynthesis-related genes in inbred lines with minor variations in dark-green leaves. We found expression differences among the inbred lines of Chinese cabbage in photosynthesis-related genes involved in the porphyrin and chlorophyll metabolism, as well as in photosynthesis and photosynthesis-antenna protein pathway. Chlorophyll b content was significantly positively correlated with the expression of PsbQ, LHCA1_1 and LHCB6_1, while chlorophyll a content was significantly negatively correlated with the expression PsbQ, LHCA1_1 and LHCA1_2. Our results provide an empirical basis for the precise identification of candidate genes and a better understanding of the molecular mechanisms responsible for the production of dark-green leaves in Chinese cabbage.
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Affiliation(s)
- Xiangjie Su
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Xiaonan Yue
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Mingyu Kong
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Ziwei Xie
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Jinghui Yan
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Wei Ma
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Yanhua Wang
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Jianjun Zhao
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Xiaomeng Zhang
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Mengyang Liu
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
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3
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Richter AS, Nägele T, Grimm B, Kaufmann K, Schroda M, Leister D, Kleine T. Retrograde signaling in plants: A critical review focusing on the GUN pathway and beyond. PLANT COMMUNICATIONS 2023; 4:100511. [PMID: 36575799 PMCID: PMC9860301 DOI: 10.1016/j.xplc.2022.100511] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 12/05/2022] [Accepted: 12/22/2022] [Indexed: 06/01/2023]
Abstract
Plastids communicate their developmental and physiological status to the nucleus via retrograde signaling, allowing nuclear gene expression to be adjusted appropriately. Signaling during plastid biogenesis and responses of mature chloroplasts to environmental changes are designated "biogenic" and "operational" controls, respectively. A prominent example of the investigation of biogenic signaling is the screen for gun (genomes uncoupled) mutants. Although the first five gun mutants were identified 30 years ago, the functions of GUN proteins in retrograde signaling remain controversial, and that of GUN1 is hotly disputed. Here, we provide background information and critically discuss recently proposed concepts that address GUN-related signaling and some novel gun mutants. Moreover, considering heme as a candidate in retrograde signaling, we revisit the spatial organization of heme biosynthesis and export from plastids. Although this review focuses on GUN pathways, we also highlight recent progress in the identification and elucidation of chloroplast-derived signals that regulate the acclimation response in green algae and plants. Here, stress-induced accumulation of unfolded/misassembled chloroplast proteins evokes a chloroplast-specific unfolded protein response, which leads to changes in the expression levels of nucleus-encoded chaperones and proteases to restore plastid protein homeostasis. We also address the importance of chloroplast-derived signals for activation of flavonoid biosynthesis leading to production of anthocyanins during stress acclimation through sucrose non-fermenting 1-related protein kinase 1. Finally, a framework for identification and quantification of intercompartmental signaling cascades at the proteomic and metabolomic levels is provided, and we discuss future directions of dissection of organelle-nucleus communication.
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Affiliation(s)
- Andreas S Richter
- Physiology of Plant Metabolism, Institute for Biosciences, University of Rostock, Albert-Einstein-Str. 3, 18059 Rostock, Germany
| | - Thomas Nägele
- Plant Evolutionary Cell Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - Bernhard Grimm
- Institute of Biology/Plant Physiology, Humboldt-Universität zu Berlin, Philippstr. 13, 10115 Berlin, Germany
| | - Kerstin Kaufmann
- Plant Cell and Molecular Biology, Institute of Biology, Humboldt-Universität zu Berlin, Philippstr. 13, 10115 Berlin, Germany
| | - Michael Schroda
- Molecular Biotechnology and Systems Biology, TU Kaiserslautern, Kaiserslautern, Germany
| | - Dario Leister
- Plant Molecular Biology (Botany), Faculty of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - Tatjana Kleine
- Plant Molecular Biology (Botany), Faculty of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany.
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Liu M, Ma W, Su X, Zhang X, Lu Y, Zhang S, Yan J, Feng D, Ma L, Taylor A, Ge Y, Cheng Q, Xu K, Wang Y, Li N, Gu A, Zhang J, Luo S, Xuan S, Chen X, Scrutton NS, Li C, Zhao J, Shen S. Mutation in a chlorophyll-binding motif of Brassica ferrochelatase enhances both heme and chlorophyll biosynthesis. Cell Rep 2022; 41:111758. [PMID: 36476857 DOI: 10.1016/j.celrep.2022.111758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 09/06/2022] [Accepted: 11/09/2022] [Indexed: 12/12/2022] Open
Abstract
The heme branch of tetrapyrrole biosynthesis contributes to the regulation of chlorophyll levels. However, the mechanism underlying the balance between chlorophyll and heme synthesis remains elusive. Here, we identify a dark green leaf mutant, dg, from an ethyl methanesulfonate (EMS)-induced mutant library of Chinese cabbage. The dg phenotype is caused by an amino acid substitution in the conserved chlorophyll a/b-binding motif (CAB) of ferrochelatase 2 (BrFC2). This mutation increases the formation of BrFC2 homodimer to promote heme production. Moreover, wild-type BrFC2 and dBrFC2 interact with protochlorophyllide (Pchlide) oxidoreductase B1 and B2 (BrPORB1 and BrPORB2), and dBrFC2 exhibits higher binding ability to substrate Pchlide, thereby promoting BrPORBs-catalyzed production of chlorophyllide (Chlide), which can be directly converted into chlorophyll. Our results show that dBrFC2 is a gain-of-function mutation contributing to balancing heme and chlorophyll synthesis via a regulatory mechanism in which dBrFC2 promotes BrPORB enzymatic reaction to enhance chlorophyll synthesis.
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Affiliation(s)
- Mengyang Liu
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Wei Ma
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Xiangjie Su
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Xiaomeng Zhang
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Yin Lu
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Shaowei Zhang
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK
| | - Jinghui Yan
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Daling Feng
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Lisong Ma
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Aoife Taylor
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK
| | - Yunjia Ge
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Qi Cheng
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Kedong Xu
- Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China
| | - Yanhua Wang
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Na Li
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Aixia Gu
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Ju Zhang
- Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China
| | - Shuangxia Luo
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Shuxin Xuan
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Xueping Chen
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
| | - Nigel S Scrutton
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK
| | - Chengwei Li
- Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001, China; College of Biological Engineering, Henan University of Technology, Zhengzhou 450001, China.
| | - Jianjun Zhao
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China.
| | - Shuxing Shen
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China.
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5
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Using Diatom and Apicomplexan Models to Study the Heme Pathway of Chromera velia. Int J Mol Sci 2021; 22:ijms22126495. [PMID: 34204357 PMCID: PMC8233740 DOI: 10.3390/ijms22126495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/11/2021] [Accepted: 06/12/2021] [Indexed: 12/20/2022] Open
Abstract
Heme biosynthesis is essential for almost all living organisms. Despite its conserved function, the pathway’s enzymes can be located in a remarkable diversity of cellular compartments in different organisms. This location does not always reflect their evolutionary origins, as might be expected from the history of their acquisition through endosymbiosis. Instead, the final subcellular localization of the enzyme reflects multiple factors, including evolutionary origin, demand for the product, availability of the substrate, and mechanism of pathway regulation. The biosynthesis of heme in the apicomonad Chromera velia follows a chimeric pathway combining heme elements from the ancient algal symbiont and the host. Computational analyses using different algorithms predict complex targeting patterns, placing enzymes in the mitochondrion, plastid, endoplasmic reticulum, or the cytoplasm. We employed heterologous reporter gene expression in the apicomplexan parasite Toxoplasma gondii and the diatom Phaeodactylum tricornutum to experimentally test these predictions. 5-aminolevulinate synthase was located in the mitochondria in both transfection systems. In T. gondii, the two 5-aminolevulinate dehydratases were located in the cytosol, uroporphyrinogen synthase in the mitochondrion, and the two ferrochelatases in the plastid. In P. tricornutum, all remaining enzymes, from ALA-dehydratase to ferrochelatase, were placed either in the endoplasmic reticulum or in the periplastidial space.
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Wang M, Gao C, Jiang T, You S, Jiang Y, Guo C, He H, Liu Y, Zhang X, Shao H, Liu H, Liang Y, Wang M, McMinn A. Genomic analysis of Synechococcus phage S-B43 and its adaption to the coastal environment. Virus Res 2020; 289:198155. [PMID: 32941942 DOI: 10.1016/j.virusres.2020.198155] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 09/01/2020] [Accepted: 09/03/2020] [Indexed: 11/17/2022]
Abstract
Synechococcus dominate picocyanobacterial communities in coastal environments. However, only a few Synechococcus phages have been described from the coastal seas of the Northwest Pacific Ocean. Here a new Synechococcus phage, S-B43 was isolated from the Bohai Sea, a semi-closed coastal sea of the Northwest Pacific Ocean. S-B43 is a member of Myoviridae, containing 275 predicted open reading frames. Fourteen auxiliary metabolic genes (AMG) were identified from the genome of S-B43, including five photosynthetic associated genes and several AMGs related to its adaption to the high turbidity and eutrophic coastal environment with a low ratio of phosphorus to nitrogen (HNLP). The occurrences of 31 AMGs among 34 cyanophage genomes indicates that AMGs zwf, gnd, speD, petF and those coding for FECH and thioredoxin were more common in coastal areas than in the open ocean and AMGs pebS and ho1 were more prevalent in the open ocean. The occurrence of cyanophage AMGs in different environments might be a reflection of the environmental adaption of their hosts. This study contributes to our understanding of the interactions between cyanobacteria and cyanophages and their environmental adaption to the coastal environment.
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Affiliation(s)
- Meiwen Wang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Chen Gao
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Tong Jiang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Siyuan You
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Yong Jiang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Cui Guo
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Hui He
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Yundan Liu
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Xinran Zhang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Hongbing Shao
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China.
| | - Hongbin Liu
- Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Yantao Liang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China.
| | - Min Wang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Andrew McMinn
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania 7001, Australia
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7
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Abstract
Modified tetrapyrroles are large macrocyclic compounds, consisting of diverse conjugation and metal chelation systems and imparting an array of colors to the biological structures that contain them. Tetrapyrroles represent some of the most complex small molecules synthesized by cells and are involved in many essential processes that are fundamental to life on Earth, including photosynthesis, respiration, and catalysis. These molecules are all derived from a common template through a series of enzyme-mediated transformations that alter the oxidation state of the macrocycle and also modify its size, its side-chain composition, and the nature of the centrally chelated metal ion. The different modified tetrapyrroles include chlorophylls, hemes, siroheme, corrins (including vitamin B12), coenzyme F430, heme d1, and bilins. After nearly a century of study, almost all of the more than 90 different enzymes that synthesize this family of compounds are now known, and expression of reconstructed operons in heterologous hosts has confirmed that most pathways are complete. Aside from the highly diverse nature of the chemical reactions catalyzed, an interesting aspect of comparative biochemistry is to see how different enzymes and even entire pathways have evolved to perform alternative chemical reactions to produce the same end products in the presence and absence of oxygen. Although there is still much to learn, our current understanding of tetrapyrrole biogenesis represents a remarkable biochemical milestone that is summarized in this review.
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Affiliation(s)
- Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717
| | - C Neil Hunter
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Martin J Warren
- School of Biosciences, University of Kent, Canterbury CT2 7NJ, United Kingdom
- Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, United Kingdom
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8
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Hey D, Grimm B. ONE-HELIX PROTEIN1 and 2 Form Heterodimers to Bind Chlorophyll in Photosystem II Biogenesis. PLANT PHYSIOLOGY 2020; 183:179-193. [PMID: 32071152 PMCID: PMC7210652 DOI: 10.1104/pp.19.01304] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 02/04/2020] [Indexed: 05/07/2023]
Abstract
Members of the light-harvesting complex protein family participate in multiple processes connected with light sensing, light absorption, and pigment binding within the thylakoid membrane. Amino acid residues of the light-harvesting chlorophyll a/b-binding proteins involved in pigment binding have been precisely identified through x-ray crystallography experiments. In vitro pigment-binding studies have been performed with LIGHT-HARVESTING-LIKE3 proteins, and the pigment-binding ability of cyanobacterial high-light-inducible proteins has been studied in detail. However, analysis of pigment binding by plant high-light-inducible protein homologs, called ONE-HELIX PROTEINS (OHPs), is lacking. Here, we report on successful in vitro reconstitution of Arabidopsis (Arabidopsis thaliana) OHPs with chlorophylls and carotenoids and show that pigment binding depends on the formation of OHP1/OHP2 heterodimers. Pigment-binding capacity was completely lost in each of the OHPs when residues of the light-harvesting complex chlorophyll-binding motif required for chlorophyll binding were mutated. Moreover, the mutated OHP variants failed to rescue the respective knockout (T-DNA insertion) mutants, indicating that pigment-binding ability is essential for OHP function in vivo. The scaffold protein HIGH CHLOROPHYLL FLUORESCENCE244 (HCF244) is tethered to the thylakoid membrane by the OHP heterodimer. We show that HCF244 stability depends on OHP heterodimer formation and introduce the concept of a functional unit consisting of OHP1, OHP2, and HCF244, in which each protein requires the others. Because of their pigment-binding capacity, we suggest that OHPs function in the delivery of pigments to the D1 subunit of PSII.
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Affiliation(s)
- Daniel Hey
- Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, Institut für Biologie, AG Pflanzenphysiologie, 10115 Berlin, Germany
| | - Bernhard Grimm
- Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, Institut für Biologie, AG Pflanzenphysiologie, 10115 Berlin, Germany
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9
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Li C, Liu X, Pan J, Guo J, Wang Q, Chen C, Li N, Zhang K, Yang B, Sun C, Deng X, Wang P. A lil3 chlp double mutant with exclusive accumulation of geranylgeranyl chlorophyll displays a lethal phenotype in rice. BMC PLANT BIOLOGY 2019; 19:456. [PMID: 31664904 PMCID: PMC6819399 DOI: 10.1186/s12870-019-2028-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 09/11/2019] [Indexed: 05/20/2023]
Abstract
BACKGROUND Phytyl residues are the common side chains of chlorophyll (Chl) and tocopherols. Geranylgeranyl reductase (GGR), which is encoded by CHLP gene, is responsible for phytyl biosynthesis. The light-harvesting like protein LIL3 was suggested to be required for stability of GGR and protochlorophyllide oxidoreductase in Arabidopsis. RESULTS In this study, we isolated a yellow-green leaf mutant, 637ys, in rice (Oryza sativa). The mutant accumulated majority of Chls with unsaturated geranylgeraniol side chains and displayed a yellow-green leaf phenotype through the whole growth period. The development of chloroplasts was suppressed, and the major agronomic traits, especially No. of productive panicles per plant and of spikelets per panicle, dramatically decreased in 637ys. Besides, the mutant exhibited to be sensitive to light intensity and deficiency of tocopherols without obvious alteration in tocotrienols in leaves and grains. Map-based cloning and complementation experiment demonstrated that a point mutation on the OsLIL3 gene accounted for the mutant phenotype of 637ys. OsLIL3 is mainly expressed in green tissues, and its encoded protein is targeted to the chloroplast. Furthermore, the 637ys 502ys (lil3 chlp) double mutant exclusively accumulated geranylgeranyl Chl and exhibited lethality at the three-leaf stage. CONCLUSIONS We identified the OsLIL3 gene through a map-based cloning approach. Meanwhile, we demonstrated that OsLIL3 is of extreme importance to the function of OsGGR, and that the complete replacement of phytyl side chain of chlorophyll by geranylgeranyl chain could be fatal to plant survival in rice.
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Affiliation(s)
- Chunmei Li
- Rice Research Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China
- Zhongkai University of Agriculture and Engineering, 24 Dongsha Street, Haizhu District, Guangzhou, 510225, China
| | - Xin Liu
- Rice Research Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China
| | - Jihong Pan
- Rice Research Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China
| | - Jia Guo
- Rice Research Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China
| | - Qian Wang
- Rice Research Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China
| | - Congping Chen
- Rice Research Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China
| | - Na Li
- Rice Research Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China
| | - Kuan Zhang
- Rice Research Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China
| | - Bin Yang
- Rice Research Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China
| | - Changhui Sun
- Rice Research Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China
| | - Xiaojian Deng
- Rice Research Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China.
| | - Pingrong Wang
- Rice Research Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, China.
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10
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Pazderník M, Mareš J, Pilný J, Sobotka R. The antenna-like domain of the cyanobacterial ferrochelatase can bind chlorophyll and carotenoids in an energy-dissipative configuration. J Biol Chem 2019; 294:11131-11143. [PMID: 31167780 DOI: 10.1074/jbc.ra119.008434] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/29/2019] [Indexed: 01/19/2023] Open
Abstract
Ferrochelatase (FeCh) is an essential enzyme catalyzing the synthesis of heme. Interestingly, in cyanobacteria, algae, and plants, FeCh possesses a conserved transmembrane chlorophyll a/b binding (CAB) domain that resembles the first and the third helix of light-harvesting complexes, including a chlorophyll-binding motif. Whether the FeCh CAB domain also binds chlorophyll is unknown. Here, using biochemical and radiolabeled precursor experiments, we found that partially inhibited activity of FeCh in the cyanobacterium Synechocystis PCC 6803 leads to overproduction of chlorophyll molecules that accumulate in the thylakoid membrane and, together with carotenoids, bind to FeCh. We observed that pigments bound to purified FeCh are organized in an energy-dissipative conformation and further show that FeCh can exist in vivo as a monomer or a dimer depending on its own activity. However, pigmented FeCh was purified exclusively as a dimer. Separately expressed and purified FeCH CAB domain contained a pigment composition similar to that of full-length FeCh and retained its quenching properties. Phylogenetic analysis suggested that the CAB domain was acquired by a fusion between FeCh and a single-helix, high light-inducible protein early in the evolution of cyanobacteria. Following this fusion, the FeCh CAB domain with a functional chlorophyll-binding motif was retained in all currently known cyanobacterial genomes except for a single lineage of endosymbiotic cyanobacteria. Our findings indicate that FeCh from Synechocystis exists mostly as a pigment-free monomer in cells but can dimerize, in which case its CAB domain creates a functional pigment-binding segment organized in an energy-dissipating configuration.
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Affiliation(s)
- Marek Pazderník
- Institute of Microbiology, Czech Academy of Sciences, Centre Algatech, Třeboň, 379 81, Czech Republic.,Faculty of Science, University of South Bohemia, České Budějovice 370 05, Czech Republic
| | - Jan Mareš
- Institute of Microbiology, Czech Academy of Sciences, Centre Algatech, Třeboň, 379 81, Czech Republic.,Faculty of Science, University of South Bohemia, České Budějovice 370 05, Czech Republic.,Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice 370 05, Czech Republic
| | - Jan Pilný
- Institute of Microbiology, Czech Academy of Sciences, Centre Algatech, Třeboň, 379 81, Czech Republic
| | - Roman Sobotka
- Institute of Microbiology, Czech Academy of Sciences, Centre Algatech, Třeboň, 379 81, Czech Republic .,Faculty of Science, University of South Bohemia, České Budějovice 370 05, Czech Republic
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11
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Fan T, Roling L, Meiers A, Brings L, Ortega-Rodés P, Hedtke B, Grimm B. Complementation studies of the Arabidopsis fc1 mutant substantiate essential functions of ferrochelatase 1 during embryogenesis and salt stress. PLANT, CELL & ENVIRONMENT 2019; 42:618-632. [PMID: 30242849 DOI: 10.1111/pce.13448] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 09/15/2018] [Accepted: 09/18/2018] [Indexed: 06/08/2023]
Abstract
Ferrochelatase (FC) is the final enzyme for haem formation in the tetrapyrrole biosynthesis pathway and encoded by two genes in higher plants. FC2 exists predominantly in green tissue, whereas FC1 is constitutively expressed. We intended to substantiate the specific roles of FC1. The embryo-lethal fc1-2 mutant was used to express the two genomic FC-encoding sequences under the FC1 and FC2 promoter and explore the complementation of the FC1 deficiency. Apart from the successful complementation with FC1, expression of FC2 under control of the FC1 promoter (pFC1::FC2) compensates for missing FC1 but not by FC2 promoter expression. The complementing lines pFC1FC2(fc1/fc1) succeeded under standard growth condition but failed under salt stress. The pFC1FC2(fc1/fc1) line exhibited symptoms of leaf senescence, including accelerated loss of haem and chlorophyll and elevated gene expression for chlorophyll catabolism. In contrast, ectopic FC1 expression (p35S::FC1) resulted in increased chlorophyll accumulation. The limited ability of FC2 to complement fc1 is explained by a faster turnover of FC2 mRNA during stress. It is suggested that FC1-produced haem is essential for embryogenesis and stress response. The pFC1::FC2 expression readily complements the fc1-2 embryo lethality, whereas higher FC1 transcript content contributes essentially to stress tolerance.
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Affiliation(s)
- Tingting Fan
- Institute of Biology/Plant Physiology, Humboldt University Berlin, Berlin, Germany
| | - Lena Roling
- Institute of Biology/Plant Physiology, Humboldt University Berlin, Berlin, Germany
| | - Anna Meiers
- Institute of Biology/Plant Physiology, Humboldt University Berlin, Berlin, Germany
| | - Lea Brings
- Institute of Biology/Plant Physiology, Humboldt University Berlin, Berlin, Germany
| | | | - Boris Hedtke
- Institute of Biology/Plant Physiology, Humboldt University Berlin, Berlin, Germany
| | - Bernhard Grimm
- Institute of Biology/Plant Physiology, Humboldt University Berlin, Berlin, Germany
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12
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Sharapova LS, Akulinkina DV, Bolychevseva YV, Elanskaya IV, Yurina NP. Study of the Location of Low-Molecular Stress-Inducible Proteins that Protect the Photosynthetic Apparatus against Photodestruction. APPL BIOCHEM MICRO+ 2019. [DOI: 10.1134/s0003683819010150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Tibiletti T, Rehman AU, Vass I, Funk C. The stress-induced SCP/HLIP family of small light-harvesting-like proteins (ScpABCDE) protects Photosystem II from photoinhibitory damages in the cyanobacterium Synechocystis sp. PCC 6803. PHOTOSYNTHESIS RESEARCH 2018; 135:103-114. [PMID: 28795265 PMCID: PMC5783992 DOI: 10.1007/s11120-017-0426-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 07/22/2017] [Indexed: 05/07/2023]
Abstract
Small CAB-like proteins (SCPs) are single-helix light-harvesting-like proteins found in all organisms performing oxygenic photosynthesis. We investigated the effect of growth in moderate salt stress on these stress-induced proteins in the cyanobacterium Synechocystis sp. PCC 6803 depleted of Photosystem I (PSI), which expresses SCPs constitutively, and compared these cells with a PSI-less/ScpABCDE- mutant. SCPs, by stabilizing chlorophyll-binding proteins and Photosystem II (PSII) assembly, protect PSII from photoinhibitory damages, and in their absence electrons accumulate and will lead to ROS formation. The presence of 0.2 M NaCl in the growth medium increased the respiratory activity and other PSII electron sinks in the PSI-less/ScpABCDE- strain. We postulate that this salt-induced effect consumes the excess of PSII-generated electrons, reduces the pressure of the electron transport chain, and thereby prevents 1O2 production.
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Affiliation(s)
- Tania Tibiletti
- Department of Chemistry, Umeå University, 90187, Umeå, Sweden
- SC Synchrotron SOLEIL, AILES beamline, L'Orme des Merisiers Saint-Aubin- BP 48, 91192, Gif-sur-Yvette, France
| | - Ateeq Ur Rehman
- Institute of Plant Biology, Biological Research Center, Szeged, Hungary
| | - Imre Vass
- Institute of Plant Biology, Biological Research Center, Szeged, Hungary
| | - Christiane Funk
- Department of Chemistry, Umeå University, 90187, Umeå, Sweden.
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14
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Chen GE, Canniffe DP, Barnett SFH, Hollingshead S, Brindley AA, Vasilev C, Bryant DA, Hunter CN. Complete enzyme set for chlorophyll biosynthesis in Escherichia coli. SCIENCE ADVANCES 2018; 4:eaaq1407. [PMID: 29387799 PMCID: PMC5787379 DOI: 10.1126/sciadv.aaq1407] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 12/28/2017] [Indexed: 05/08/2023]
Abstract
Chlorophylls are essential cofactors for photosynthesis, which sustains global food chains and oxygen production. Billions of tons of chlorophylls are synthesized annually, yet full understanding of chlorophyll biosynthesis has been hindered by the lack of characterization of the Mg-protoporphyrin IX monomethyl ester oxidative cyclase step, which confers the distinctive green color of these pigments. We demonstrate cyclase activity using heterologously expressed enzyme. Next, we assemble a genetic module that encodes the complete chlorophyll biosynthetic pathway and show that it functions in Escherichia coli. Expression of 12 genes converts endogenous protoporphyrin IX into chlorophyll a, turning E. coli cells green. Our results delineate a minimum set of enzymes required to make chlorophyll and establish a platform for engineering photosynthesis in a heterotrophic model organism.
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Affiliation(s)
- Guangyu E. Chen
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Daniel P. Canniffe
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Samuel F. H. Barnett
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Sarah Hollingshead
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Amanda A. Brindley
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Cvetelin Vasilev
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Donald A. Bryant
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA
| | - C. Neil Hunter
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
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15
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Chidgey JW, Jackson PJ, Dickman MJ, Hunter CN. PufQ regulates porphyrin flux at the haem/bacteriochlorophyll branchpoint of tetrapyrrole biosynthesis via interactions with ferrochelatase. Mol Microbiol 2017; 106:961-975. [PMID: 29030914 PMCID: PMC5725709 DOI: 10.1111/mmi.13861] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/12/2017] [Indexed: 11/29/2022]
Abstract
Facultative phototrophs such as Rhodobacter sphaeroides can switch between heterotrophic and photosynthetic growth. This transition is governed by oxygen tension and involves the large-scale production of bacteriochlorophyll, which shares a biosynthetic pathway with haem up to protoporphyrin IX. Here, the pathways diverge with the insertion of Fe2+ or Mg2+ into protoporphyrin by ferrochelatase or magnesium chelatase, respectively. Tight regulation of this branchpoint is essential, but the mechanisms for switching between respiratory and photosynthetic growth are poorly understood. We show that PufQ governs the haem/bacteriochlorophyll switch; pufQ is found within the oxygen-regulated pufQBALMX operon encoding the reaction centre-light-harvesting photosystem complex. A pufQ deletion strain synthesises low levels of bacteriochlorophyll and accumulates the biosynthetic precursor coproporphyrinogen III; a suppressor mutant of this strain harbours a mutation in the hemH gene encoding ferrochelatase, substantially reducing ferrochelatase activity and increasing cellular bacteriochlorophyll levels. FLAG-immunoprecipitation experiments retrieve a ferrochelatase-PufQ-carotenoid complex, proposed to regulate the haem/bacteriochlorophyll branchpoint by directing porphyrin flux toward bacteriochlorophyll production under oxygen-limiting conditions. The co-location of pufQ and the photosystem genes in the same operon ensures that switching of tetrapyrrole metabolism toward bacteriochlorophyll is coordinated with the production of reaction centre and light-harvesting polypeptides.
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Affiliation(s)
- Jack W. Chidgey
- Department of Molecular Biology and BiotechnologyUniversity of SheffieldSheffield S10 2TNUK
| | - Philip J. Jackson
- Department of Molecular Biology and BiotechnologyUniversity of SheffieldSheffield S10 2TNUK
- ChELSI Institute, Department of Chemical and Biological EngineeringUniversity of SheffieldSheffield S1 3JDUK
| | - Mark J. Dickman
- ChELSI Institute, Department of Chemical and Biological EngineeringUniversity of SheffieldSheffield S1 3JDUK
| | - C. Neil Hunter
- Department of Molecular Biology and BiotechnologyUniversity of SheffieldSheffield S10 2TNUK
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16
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Zhao WT, Feng SJ, Li H, Faust F, Kleine T, Li LN, Yang ZM. Salt stress-induced FERROCHELATASE 1 improves resistance to salt stress by limiting sodium accumulation in Arabidopsis thaliana. Sci Rep 2017; 7:14737. [PMID: 29116128 PMCID: PMC5676718 DOI: 10.1038/s41598-017-13593-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 05/09/2017] [Indexed: 12/15/2022] Open
Abstract
Ferrochelatase-1 as a terminal enzyme of heme biosynthesis regulates many essential metabolic and physiological processes. Whether FC1 is involved in plant response to salt stress has not been described. This study shows that Arabidopsis overexpressing AtFC1 displays resistance to high salinity, whereas a T-DNA insertion knock-down mutant fc1 was more sensitive to salt stress than wild-type plants. AtFC1 conferred plant salt resistance by reducing Na+ concentration, enhancing K+ accumulation and preventing lysis of the cell membrane. Such observations were associated with the upregulation of SOS1, which encodes a plasma membrane Na+/H+ antiporter. AtFC1 overexpression led to a reduced expression of several well known salt stress-responsive genes such as NHX1 and AVP1, suggesting that AtFC1-regulated low concentration of Na+ in plants might not be through the mechanism for Na+ sequestration. To investigate the mechanism leading to the role of AtFC1 in mediating salt stress response in plants, a transcriptome of fc1 mutant plants under salt stress was profiled. Our data show that mutation of AtFC1 led to 490 specific genes up-regulated and 380 specific genes down-regulated in fc1 mutants under salt stress. Some of the genes are involved in salt-induced oxidative stress response, monovalent cation-proton (Na+/H+) exchange, and Na+ detoxification.
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Affiliation(s)
- Wen Ting Zhao
- Department of Biochemistry and Molecular Biology, College of Life Science, Nanjing Agricultural University, Nanjing, 210095, China.,Institute of Plant Nutrition (IFZ), Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
| | - Sheng Jun Feng
- Department of Biochemistry and Molecular Biology, College of Life Science, Nanjing Agricultural University, Nanjing, 210095, China
| | - Hua Li
- Department of Plant Science, College of Life Science, Henan Agricultural University, Henan, 450002, China
| | - Franziska Faust
- Institute of Plant Nutrition (IFZ), Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
| | - Tatjana Kleine
- Plant Molecular Biology (Botany), Department Biology I, Ludwig-Maximilians-University Munich, 82152, Martinsried, Germany
| | - Long Na Li
- Department of Biochemistry and Molecular Biology, College of Life Science, Nanjing Agricultural University, Nanjing, 210095, China
| | - Zhi Min Yang
- Department of Biochemistry and Molecular Biology, College of Life Science, Nanjing Agricultural University, Nanjing, 210095, China.
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17
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Angerer V, Schwenk P, Wallner T, Kaever V, Hiltbrunner A, Wilde A. The protein Slr1143 is an active diguanylate cyclase in Synechocystis sp. PCC 6803 and interacts with the photoreceptor Cph2. Microbiology (Reading) 2017. [DOI: 10.1099/mic.0.000475] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Veronika Angerer
- Institute for Biology III, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Philipp Schwenk
- Institute for Biology II, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
- Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, 79104 Freiburg, Germany
| | - Thomas Wallner
- Institute for Biology III, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Volkhard Kaever
- Research Core Unit Metabolomics, Hannover Medical School, 30623 Hannover, Germany
| | - Andreas Hiltbrunner
- Institute for Biology II, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
- Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, 79104 Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Annegret Wilde
- Institute for Biology III, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
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18
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Hey D, Rothbart M, Herbst J, Wang P, Müller J, Wittmann D, Gruhl K, Grimm B. LIL3, a Light-Harvesting Complex Protein, Links Terpenoid and Tetrapyrrole Biosynthesis in Arabidopsis thaliana. PLANT PHYSIOLOGY 2017; 174:1037-1050. [PMID: 28432258 PMCID: PMC5462053 DOI: 10.1104/pp.17.00505] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 04/19/2017] [Indexed: 05/18/2023]
Abstract
The LIL3 protein of Arabidopsis (Arabidopsis thaliana) belongs to the light-harvesting complex (LHC) protein family, which also includes the light-harvesting chlorophyll-binding proteins of photosystems I and II, the early-light-inducible proteins, PsbS involved in nonphotochemical quenching, and the one-helix proteins and their cyanobacterial homologs designated high-light-inducible proteins. Each member of this family is characterized by one or two LHC transmembrane domains (referred to as the LHC motif) to which potential functions such as chlorophyll binding, protein interaction, and integration of interacting partners into the plastid membranes have been attributed. Initially, LIL3 was shown to interact with geranylgeranyl reductase (CHLP), an enzyme of terpene biosynthesis that supplies the hydrocarbon chain for chlorophyll and tocopherol. Here, we show another function of LIL3 for the stability of protochlorophyllide oxidoreductase (POR). Multiple protein-protein interaction analyses suggest the direct physical interaction of LIL3 with POR but not with chlorophyll synthase. Consistently, LIL3-deficient plants exhibit substantial loss of POR as well as CHLP, which is not due to defective transcription of the POR and CHLP genes but to the posttranslational modification of their protein products. Interestingly, in vitro biochemical analyses provide novel evidence that LIL3 shows high binding affinity to protochlorophyllide, the substrate of POR. Taken together, this study suggests a critical role for LIL3 in the organization of later steps in chlorophyll biosynthesis. We suggest that LIL3 associates with POR and CHLP and thus contributes to the supply of the two metabolites, chlorophyllide and phytyl pyrophosphate, required for the final step in chlorophyll a synthesis.
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Affiliation(s)
- Daniel Hey
- Humboldt Universität zu Berlin, Lebenswissenschaftliche Fakultät, Institut für Biologie, AG Pflanzenphysiologie, 10115 Berlin, Germany
| | - Maxi Rothbart
- Humboldt Universität zu Berlin, Lebenswissenschaftliche Fakultät, Institut für Biologie, AG Pflanzenphysiologie, 10115 Berlin, Germany
| | - Josephine Herbst
- Humboldt Universität zu Berlin, Lebenswissenschaftliche Fakultät, Institut für Biologie, AG Pflanzenphysiologie, 10115 Berlin, Germany
| | - Peng Wang
- Humboldt Universität zu Berlin, Lebenswissenschaftliche Fakultät, Institut für Biologie, AG Pflanzenphysiologie, 10115 Berlin, Germany
| | - Jakob Müller
- Humboldt Universität zu Berlin, Lebenswissenschaftliche Fakultät, Institut für Biologie, AG Pflanzenphysiologie, 10115 Berlin, Germany
| | - Daniel Wittmann
- Humboldt Universität zu Berlin, Lebenswissenschaftliche Fakultät, Institut für Biologie, AG Pflanzenphysiologie, 10115 Berlin, Germany
| | - Kirsten Gruhl
- Humboldt Universität zu Berlin, Lebenswissenschaftliche Fakultät, Institut für Biologie, AG Pflanzenphysiologie, 10115 Berlin, Germany
| | - Bernhard Grimm
- Humboldt Universität zu Berlin, Lebenswissenschaftliche Fakultät, Institut für Biologie, AG Pflanzenphysiologie, 10115 Berlin, Germany
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19
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Conserved residues in Ycf54 are required for protochlorophyllide formation in Synechocystis sp. PCC 6803. Biochem J 2017; 474:667-681. [PMID: 28008132 PMCID: PMC5317394 DOI: 10.1042/bcj20161002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 12/13/2016] [Accepted: 12/20/2016] [Indexed: 11/24/2022]
Abstract
Chlorophylls (Chls) are modified tetrapyrrole molecules, essential for photosynthesis. These pigments possess an isocyclic E ring formed by the Mg-protoporphyrin IX monomethylester cyclase (MgPME–cyclase). We assessed the in vivo effects of altering seven highly conserved residues within Ycf54, which is required for MgPME–cyclase activity in the cyanobacterium Synechocystis. Synechocystis strains harbouring the Ycf54 alterations D39A, F40A and R82A were blocked to varying degrees at the MgPME–cyclase step, whereas the A9G mutation reduced Ycf54 levels by ∼75%. Wild-type (WT) levels of the cyclase subunit CycI are present in strains with D39A and F40A, but these strains have lowered cellular Chl and photosystem accumulation. CycI is reduced by ∼50% in A9G and R82A, but A9G has no perturbations in Chl or photosystem accumulation, whilst R82A contains very little Chl and few photosystems. When FLAG tagged and used as bait in pulldown experiments, the three mutants D39A, F40A and R82A were unable to interact with the MgPME–cyclase component CycI, whereas A9G pulled down a similar level of CycI as WT Ycf54. These observations suggest that a stable interaction between CycI and Ycf54 is required for unimpeded Pchlide biosynthesis. Crystal structures of the WT, A9G and R82A Ycf54 proteins were solved and analysed to investigate the structural effects of these mutations. A loss of the local hydrogen bonding network and a reversal in the surface charge surrounding residue R82 are probably responsible for the functional differences observed in the R82A mutation. We conclude that the Ycf54 protein must form a stable interaction with CycI to promote optimal Pchlide biosynthesis.
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20
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Hey D, Ortega-Rodes P, Fan T, Schnurrer F, Brings L, Hedtke B, Grimm B. Transgenic Tobacco Lines Expressing Sense or Antisense FERROCHELATASE 1 RNA Show Modified Ferrochelatase Activity in Roots and Provide Experimental Evidence for Dual Localization of Ferrochelatase 1. PLANT & CELL PHYSIOLOGY 2016; 57:2576-2585. [PMID: 27818378 DOI: 10.1093/pcp/pcw171] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 10/03/2016] [Indexed: 06/06/2023]
Abstract
In plants, two genes encode ferrochelatase (FC), which catalyzes iron chelation into protoporphyrin IX at the final step of heme biosynthesis. FERROCHELATASE1 (FC1) is continuously, but weakly expressed in roots and leaves, while FC2 is dominantly active in leaves. As a continuation of previous studies on the physiological consequences of FC2 inactivation in tobacco, we aimed to assign FC1 function in plant organs. While reduced FC2 expression leads to protoporphyrin IX accumulation in leaves, FC1 down-regulation and overproduction caused reduced and elevated FC activity in root tissue, respectively, but were not associated with changes in macroscopic phenotype, plant development or leaf pigmentation. In contrast to the lower heme content resulting from a deficiency of the dominant FC2 expression in leaves, a reduction of FC1 in roots and leaves does not significantly disturb heme accumulation. The FC1 overexpression was used for an additional approach to re-examine FC activity in mitochondria. Transgenic FC1 protein was immunologically shown to be present in mitochondria. Although matching only a small portion of total cellular FC activity, the mitochondrial FC activity in a FC1 overexpressor line increased 5-fold in comparison with wild-type mitochondria. Thus, it is suggested that FC1 contributes to mitochondrial heme synthesis.
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Affiliation(s)
- Daniel Hey
- Humboldt-University Berlin, Institute of Biology/Plant Physiology, Philippstr.13, Building 12, D-10115 Berlin, Germany
| | - Patricia Ortega-Rodes
- Humboldt-University Berlin, Institute of Biology/Plant Physiology, Philippstr.13, Building 12, D-10115 Berlin, Germany
| | - Tingting Fan
- Humboldt-University Berlin, Institute of Biology/Plant Physiology, Philippstr.13, Building 12, D-10115 Berlin, Germany
| | - Florian Schnurrer
- Humboldt-University Berlin, Institute of Biology/Plant Physiology, Philippstr.13, Building 12, D-10115 Berlin, Germany
| | - Lea Brings
- Humboldt-University Berlin, Institute of Biology/Plant Physiology, Philippstr.13, Building 12, D-10115 Berlin, Germany
| | - Boris Hedtke
- Humboldt-University Berlin, Institute of Biology/Plant Physiology, Philippstr.13, Building 12, D-10115 Berlin, Germany
| | - Bernhard Grimm
- Humboldt-University Berlin, Institute of Biology/Plant Physiology, Philippstr.13, Building 12, D-10115 Berlin, Germany
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Deletion of the gene family of small chlorophyll-binding proteins (ScpABCDE) offsets C/N homeostasis in Synechocystis PCC 6803. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:396-407. [DOI: 10.1016/j.bbabio.2015.11.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 11/20/2015] [Accepted: 11/27/2015] [Indexed: 02/03/2023]
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Komenda J, Sobotka R. Cyanobacterial high-light-inducible proteins — Protectors of chlorophyll–protein synthesis and assembly. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:288-95. [DOI: 10.1016/j.bbabio.2015.08.011] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 08/28/2015] [Accepted: 08/30/2015] [Indexed: 12/24/2022]
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Hollingshead S, Kopečná J, Armstrong DR, Bučinská L, Jackson PJ, Chen GE, Dickman MJ, Williamson MP, Sobotka R, Hunter CN. Synthesis of Chlorophyll-Binding Proteins in a Fully Segregated Δycf54 Strain of the Cyanobacterium Synechocystis PCC 6803. FRONTIERS IN PLANT SCIENCE 2016; 7:292. [PMID: 27014315 PMCID: PMC4794507 DOI: 10.3389/fpls.2016.00292] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 02/23/2016] [Indexed: 05/07/2023]
Abstract
In the chlorophyll (Chl) biosynthesis pathway the formation of protochlorophyllide is catalyzed by Mg-protoporphyrin IX methyl ester (MgPME) cyclase. The Ycf54 protein was recently shown to form a complex with another component of the oxidative cyclase, Sll1214 (CycI), and partial inactivation of the ycf54 gene leads to Chl deficiency in cyanobacteria and plants. The exact function of the Ycf54 is not known, however, and further progress depends on construction and characterization of a mutant cyanobacterial strain with a fully inactivated ycf54 gene. Here, we report the complete deletion of the ycf54 gene in the cyanobacterium Synechocystis 6803; the resulting Δycf54 strain accumulates huge concentrations of the cyclase substrate MgPME together with another pigment, which we identified using nuclear magnetic resonance as 3-formyl MgPME. The detection of a small amount (~13%) of Chl in the Δycf54 mutant provides clear evidence that the Ycf54 protein is important, but not essential, for activity of the oxidative cyclase. The greatly reduced formation of protochlorophyllide in the Δycf54 strain provided an opportunity to use (35)S protein labeling combined with 2D electrophoresis to examine the synthesis of all known Chl-binding protein complexes under drastically restricted de novo Chl biosynthesis. We show that although the Δycf54 strain synthesizes very limited amounts of photosystem I and the CP47 and CP43 subunits of photosystem II (PSII), the synthesis of PSII D1 and D2 subunits and their assembly into the reaction centre (RCII) assembly intermediate were not affected. Furthermore, the levels of other Chl complexes such as cytochrome b 6 f and the HliD- Chl synthase remained comparable to wild-type. These data demonstrate that the requirement for de novo Chl molecules differs completely for each Chl-binding protein. Chl traffic and recycling in the cyanobacterial cell as well as the function of Ycf54 are discussed.
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Affiliation(s)
- Sarah Hollingshead
- Department of Molecular Biology and Biotechnology, University of SheffieldSheffield, UK
- Sir William Dunn School of Pathology, University of OxfordOxford, UK
| | - Jana Kopečná
- Institute of Microbiology, Centre Algatech, Academy of Sciences of the Czech RepublicTřeboň, Czech Republic
| | - David R. Armstrong
- Department of Molecular Biology and Biotechnology, University of SheffieldSheffield, UK
| | - Lenka Bučinská
- Institute of Microbiology, Centre Algatech, Academy of Sciences of the Czech RepublicTřeboň, Czech Republic
- Faculty of Science, University of South BohemiaČeské Budějovice, Czech Republic
| | - Philip J. Jackson
- Department of Molecular Biology and Biotechnology, University of SheffieldSheffield, UK
- ChELSI Institute, Department of Chemical and Biological Engineering, University of SheffieldSheffield, UK
| | - Guangyu E. Chen
- Department of Molecular Biology and Biotechnology, University of SheffieldSheffield, UK
| | - Mark J. Dickman
- ChELSI Institute, Department of Chemical and Biological Engineering, University of SheffieldSheffield, UK
| | - Michael P. Williamson
- Department of Molecular Biology and Biotechnology, University of SheffieldSheffield, UK
| | - Roman Sobotka
- Institute of Microbiology, Centre Algatech, Academy of Sciences of the Czech RepublicTřeboň, Czech Republic
- Faculty of Science, University of South BohemiaČeské Budějovice, Czech Republic
| | - C. Neil Hunter
- Department of Molecular Biology and Biotechnology, University of SheffieldSheffield, UK
- *Correspondence: C. Neil Hunter,
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Espinas NA, Kobayashi K, Sato Y, Mochizuki N, Takahashi K, Tanaka R, Masuda T. Allocation of Heme Is Differentially Regulated by Ferrochelatase Isoforms in Arabidopsis Cells. FRONTIERS IN PLANT SCIENCE 2016; 7:1326. [PMID: 27630653 PMCID: PMC5005420 DOI: 10.3389/fpls.2016.01326] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 08/18/2016] [Indexed: 05/03/2023]
Abstract
Heme is involved in various biological processes as a cofactor of hemoproteins located in various organelles. In plant cells, heme is synthesized by two isoforms of plastid-localized ferrochelatase, FC1 and FC2. In this study, by characterizing Arabidopsis T-DNA insertional mutants, we showed that the allocation of heme is differentially regulated by ferrochelatase isoforms in plant cells. Analyses of weak (fc1-1) and null (fc1-2) mutants suggest that FC1-producing heme is required for initial growth of seedling development. In contrast, weak (fc2-1) and null (fc2-2) mutants of FC2 showed pale green leaves and retarded growth, indicating that FC2-producing heme is necessary for chloroplast development. During the initial growth stage, FC2 deficiency caused reduction of plastid cytochromes. In addition, although FC2 deficiency marginally affected the assembly of photosynthetic reaction center complexes, it caused relatively larger but insufficient light-harvesting antenna to reaction centers, resulting in lower efficiency of photosynthesis. In the later vegetative growth, however, fc2-2 recovered photosynthetic growth, showing that FC1-producing heme may complement the FC2 deficiency. On the other hand, reduced level of cytochromes in microsomal fraction was discovered in fc1-1, suggesting that FC1-producing heme is mainly allocated to extraplastidic organelles. Furthermore, the expression of FC1 is induced by the treatment of an elicitor flg22 while that of FC2 was reduced, and fc1-1 abolished the flg22-dependent induction of FC1 expression and peroxidase activity. Consequently, our results clarified that FC2 produces heme for the photosynthetic machinery in the chloroplast, while FC1 is the housekeeping enzyme providing heme cofactor to the entire cell. In addition, FC1 can partly complement FC2 deficiency and is also involved in defense against stressful conditions.
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Affiliation(s)
- Nino A. Espinas
- Graduate School of Science, The University of TokyoTokyo, Japan
| | - Koichi Kobayashi
- Graduate School of Arts and Sciences, The University of TokyoTokyo, Japan
| | - Yasushi Sato
- Graduate School of Science and Engineering, Ehime UniversityEhime, Japan
| | | | - Kaori Takahashi
- Institute of Low Temperature Science, Hokkaido UniversitySapporo, Japan
| | - Ryouichi Tanaka
- Institute of Low Temperature Science, Hokkaido UniversitySapporo, Japan
| | - Tatsuru Masuda
- Graduate School of Science, The University of TokyoTokyo, Japan
- Graduate School of Arts and Sciences, The University of TokyoTokyo, Japan
- *Correspondence: Tatsuru Masuda,
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Wang P, Grimm B. Organization of chlorophyll biosynthesis and insertion of chlorophyll into the chlorophyll-binding proteins in chloroplasts. PHOTOSYNTHESIS RESEARCH 2015; 126:189-202. [PMID: 25957270 DOI: 10.1007/s11120-015-0154-5] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 04/30/2015] [Indexed: 05/23/2023]
Abstract
Oxygenic photosynthesis requires chlorophyll (Chl) for the absorption of light energy, and charge separation in the reaction center of photosystem I and II, to feed electrons into the photosynthetic electron transfer chain. Chl is bound to different Chl-binding proteins assembled in the core complexes of the two photosystems and their peripheral light-harvesting antenna complexes. The structure of the photosynthetic protein complexes has been elucidated, but mechanisms of their biogenesis are in most instances unknown. These processes involve not only the assembly of interacting proteins, but also the functional integration of pigments and other cofactors. As a precondition for the association of Chl with the Chl-binding proteins in both photosystems, the synthesis of the apoproteins is synchronized with Chl biosynthesis. This review aims to summarize the present knowledge on the posttranslational organization of Chl biosynthesis and current attempts to envision the proceedings of the successive synthesis and integration of Chl into Chl-binding proteins in the thylakoid membrane. Potential auxiliary factors, contributing to the control and organization of Chl biosynthesis and the association of Chl with the Chl-binding proteins during their integration into photosynthetic complexes, are discussed in this review.
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Affiliation(s)
- Peng Wang
- Institute of Biology/Plant Physiology, Humboldt-University Berlin, Philippstraße 13, 10115, Berlin, Germany
| | - Bernhard Grimm
- Institute of Biology/Plant Physiology, Humboldt-University Berlin, Philippstraße 13, 10115, Berlin, Germany.
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26
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Scharfenberg M, Mittermayr L, VON Roepenack-Lahaye E, Schlicke H, Grimm B, Leister D, Kleine T. Functional characterization of the two ferrochelatases in Arabidopsis thaliana. PLANT, CELL & ENVIRONMENT 2015; 38:280-98. [PMID: 24329537 DOI: 10.1111/pce.12248] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2013] [Revised: 11/19/2013] [Accepted: 11/21/2013] [Indexed: 05/03/2023]
Abstract
The enzyme ferrochelatase catalyses the formation of protoheme by inserting Fe(2+) into protoporphyrin IX. Although most organisms express only one ferrochelatase, all land plants analysed so far possess at least two ferrochelatase proteins. Analysis of publicly available expression data suggests that the two Arabidopsis thaliana ferrochelatases, FC1 and FC2, serve different functions, corroborating previous assumptions. Co-expression analysis of FC1 and FC2, together with microarray analyses, implies that fc1 and fc2 trigger different modes of plastid signalling in roots and leaves, respectively, and indicates that FC2 might be involved in stress responses. Thus, loss of FC2 increases resistance to salt and flagellin treatment. Whereas fc1 plants showed no obvious mutant phenotype, fc2 mutants formed abnormally small, pale green rosette leaves; were low in chlorophylls, carotenoids and several photosynthetic proteins; and their photosynthetic performance was impaired. These phenotypes are attenuated by growth in continuous light, in agreement with the finding that fc2 plants accumulate protochlorophyllide and display a fluorescent (flu) phenotype in the dark. In consequence we show that, contrary to earlier suggestions, FC2 produces heme not only for photosynthetic cytochromes, but also for proteins involved in stress responses, whereas the impairment of FC1 apparently interferes only marginally with stress responses.
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Affiliation(s)
- Michael Scharfenberg
- Plant Molecular Biology (Botany), Department Biology I, Ludwig-Maximilians-University Munich, 82152, Martinsried, Germany
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27
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Chidgey JW, Linhartová M, Komenda J, Jackson PJ, Dickman MJ, Canniffe DP, Koník P, Pilný J, Hunter CN, Sobotka R. A cyanobacterial chlorophyll synthase-HliD complex associates with the Ycf39 protein and the YidC/Alb3 insertase. THE PLANT CELL 2014; 26:1267-79. [PMID: 24681617 PMCID: PMC4001383 DOI: 10.1105/tpc.114.124495] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Macromolecular membrane assemblies of chlorophyll-protein complexes efficiently harvest and trap light energy for photosynthesis. To investigate the delivery of chlorophylls to the newly synthesized photosystem apoproteins, a terminal enzyme of chlorophyll biosynthesis, chlorophyll synthase (ChlG), was tagged in the cyanobacterium Synechocystis PCC 6803 (Synechocystis) and used as bait in pull-down experiments. We retrieved an enzymatically active complex comprising ChlG and the high-light-inducible protein HliD, which associates with the Ycf39 protein, a putative assembly factor for photosystem II, and with the YidC/Alb3 insertase. 2D electrophoresis and immunoblotting also provided evidence for the presence of SecY and ribosome subunits. The isolated complex contained chlorophyll, chlorophyllide, and carotenoid pigments. Deletion of hliD elevated the level of the ChlG substrate, chlorophyllide, more than 6-fold; HliD is apparently required for assembly of FLAG-ChlG into larger complexes with other proteins such as Ycf39. These data reveal a link between chlorophyll biosynthesis and the Sec/YidC-dependent cotranslational insertion of nascent photosystem polypeptides into membranes. We expect that this close physical linkage coordinates the arrival of pigments and nascent apoproteins to produce photosynthetic pigment-protein complexes with minimal risk of accumulating phototoxic unbound chlorophylls.
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Affiliation(s)
- Jack W. Chidgey
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Markéta Linhartová
- Institute of Microbiology, Academy of Sciences, 37981 Třeboň, Czech Republic
- Faculty of Sciences, University of South Bohemia, 370 05 České Budějovice, Czech Republic
| | - Josef Komenda
- Institute of Microbiology, Academy of Sciences, 37981 Třeboň, Czech Republic
- Faculty of Sciences, University of South Bohemia, 370 05 České Budějovice, Czech Republic
| | - Philip J. Jackson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
- ChELSI Institute, Department of Chemical and Biological Engineering, University of Sheffield, Sheffield S1 3JD, United Kingdom
| | - Mark J. Dickman
- ChELSI Institute, Department of Chemical and Biological Engineering, University of Sheffield, Sheffield S1 3JD, United Kingdom
| | - Daniel P. Canniffe
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Peter Koník
- Faculty of Sciences, University of South Bohemia, 370 05 České Budějovice, Czech Republic
| | - Jan Pilný
- Institute of Microbiology, Academy of Sciences, 37981 Třeboň, Czech Republic
| | - C. Neil Hunter
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
- Address correspondence to
| | - Roman Sobotka
- Institute of Microbiology, Academy of Sciences, 37981 Třeboň, Czech Republic
- Faculty of Sciences, University of South Bohemia, 370 05 České Budějovice, Czech Republic
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Sobotka R. Making proteins green; biosynthesis of chlorophyll-binding proteins in cyanobacteria. PHOTOSYNTHESIS RESEARCH 2014; 119:223-32. [PMID: 23377990 DOI: 10.1007/s11120-013-9797-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2012] [Accepted: 01/10/2013] [Indexed: 05/20/2023]
Abstract
Chlorophyll (Chl) is an essential component of the photosynthetic apparatus. Embedded into Chl-binding proteins, Chl molecules play a central role in light harvesting and charge separation within the photosystems. It is critical for the photosynthetic cell to not only ensure the synthesis of a sufficient amount of new Chl-binding proteins but also avoids any misbalance between apoprotein synthesis and the formation of potentially phototoxic Chl molecules. According to the available data, Chl-binding proteins are translated on membrane bound ribosomes and their integration into the membrane is provided by the SecYEG/Alb3 translocon machinery. It appears that the insertion of Chl molecules into growing polypeptide is a prerequisite for the correct folding and finishing of Chl-binding protein synthesis. Although the Chl biosynthetic pathway is fairly well-described on the level of enzymatic steps, a link between Chl biosynthesis and the synthesis of apoproteins remains elusive. In this review, I summarize the current knowledge about this issue putting emphasis on protein-protein interactions. I present a model of the Chl biosynthetic pathway organized into a multi-enzymatic complex and physically attached to the SecYEG/Alb3 translocon. Localization of this hypothetical large biosynthetic centre in the cyanobacterial cell is also discussed as well as regulatory mechanisms coordinating the rate of Chl and apoprotein synthesis.
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Affiliation(s)
- Roman Sobotka
- Institute of Microbiology CAS, Opatovický mlyn, Třeboň, Czech Republic,
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Takahashi K, Takabayashi A, Tanaka A, Tanaka R. Functional analysis of light-harvesting-like protein 3 (LIL3) and its light-harvesting chlorophyll-binding motif in Arabidopsis. J Biol Chem 2013; 289:987-99. [PMID: 24275650 DOI: 10.1074/jbc.m113.525428] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The light-harvesting complex (LHC) constitutes the major light-harvesting antenna of photosynthetic eukaryotes. LHC contains a characteristic sequence motif, termed LHC motif, consisting of 25-30 mostly hydrophobic amino acids. This motif is shared by a number of transmembrane proteins from oxygenic photoautotrophs that are termed light-harvesting-like (LIL) proteins. To gain insights into the functions of LIL proteins and their LHC motifs, we functionally characterized a plant LIL protein, LIL3. This protein has been shown previously to stabilize geranylgeranyl reductase (GGR), a key enzyme in phytol biosynthesis. It is hypothesized that LIL3 functions to anchor GGR to membranes. First, we conjugated the transmembrane domain of LIL3 or that of ascorbate peroxidase to GGR and expressed these chimeric proteins in an Arabidopsis mutant lacking LIL3 protein. As a result, the transgenic plants restored phytol-synthesizing activity. These results indicate that GGR is active as long as it is anchored to membranes, even in the absence of LIL3. Subsequently, we addressed the question why the LHC motif is conserved in the LIL3 sequences. We modified the transmembrane domain of LIL3, which contains the LHC motif, by substituting its conserved amino acids (Glu-171, Asn-174, and Asp-189) with alanine. As a result, the Arabidopsis transgenic plants partly recovered the phytol-biosynthesizing activity. However, in these transgenic plants, the LIL3-GGR complexes were partially dissociated. Collectively, these results indicate that the LHC motif of LIL3 is involved in the complex formation of LIL3 and GGR, which might contribute to the GGR reaction.
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Affiliation(s)
- Kaori Takahashi
- From the Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan and
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30
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Storm P, Tibiletti T, Hall M, Funk C. Refolding and enzyme kinetic studies on the ferrochelatase of the cyanobacterium Synechocystis sp. PCC 6803. PLoS One 2013; 8:e55569. [PMID: 23390541 PMCID: PMC3563542 DOI: 10.1371/journal.pone.0055569] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 12/27/2012] [Indexed: 11/19/2022] Open
Abstract
Heme is a cofactor for proteins participating in many important cellular processes, including respiration, oxygen metabolism and oxygen binding. The key enzyme in the heme biosynthesis pathway is ferrochelatase (protohaem ferrolyase, EC 4.99.1.1), which catalyzes the insertion of ferrous iron into protoporphyrin IX. In higher plants, the ferrochelatase enzyme is localized not only in mitochondria, but also in chloroplasts. The plastidic type II ferrochelatase contains a C-terminal chlorophyll a/b (CAB) motif, a conserved hydrophobic stretch homologous to the CAB domain of plant light harvesting proteins and light-harvesting like proteins. This type II ferrochelatase, found in all photosynthetic organisms, is presumed to have evolved from the cyanobacterial ferrochelatase. Here we describe a detailed enzymological study on recombinant, refolded and functionally active type II ferrochelatase (FeCh) from the cyanobacterium Synechocystis sp. PCC 6803. A protocol was developed for the functional refolding and purification of the recombinant enzyme from inclusion bodies, without truncation products or soluble aggregates. The refolded FeCh is active in its monomeric form, however, addition of an N-terminal His6-tag has significant effects on its enzyme kinetics. Strikingly, removal of the C-terminal CAB-domain led to a greatly increased turnover number, kcat, compared to the full length protein. While pigments isolated from photosynthetic membranes decrease the activity of FeCh, direct pigment binding to the CAB domain of FeCh was not evident.
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Affiliation(s)
- Patrik Storm
- Deptartment of Chemistry and Umeå Plant Science Centre, Umeå University, Umeå, Sweden
| | - Tania Tibiletti
- Deptartment of Chemistry and Umeå Plant Science Centre, Umeå University, Umeå, Sweden
| | - Michael Hall
- Deptartment of Chemistry and Umeå Plant Science Centre, Umeå University, Umeå, Sweden
| | - Christiane Funk
- Deptartment of Chemistry and Umeå Plant Science Centre, Umeå University, Umeå, Sweden
- * E-mail:
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Barajas-López JDD, Blanco NE, Strand Å. Plastid-to-nucleus communication, signals controlling the running of the plant cell. BIOCHIMICA ET BIOPHYSICA ACTA 2013. [PMID: 22749883 DOI: 10.1016/j.bbamcr.2012.06.020 [epub ahead of print]] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The presence of genes encoding organellar proteins in both the nucleus and the organelle necessitates tight coordination of expression by the different genomes, and this has led to the evolution of sophisticated intracellular signaling networks. Organelle-to-nucleus signaling, or retrograde control, coordinates the expression of nuclear genes encoding organellar proteins with the metabolic and developmental state of the organelle. Complex networks of retrograde signals orchestrate major changes in nuclear gene expression and coordinate cellular activities and assist the cell during plant development and stress responses. It has become clear that, even though the chloroplast depends on the nucleus for its function, plastid signals play important roles in an array of different cellular processes vital to the plant. Hence, the chloroplast exerts significant control over the running of the cell. This article is part of a Special Issue entitled: Protein Import and Quality Control in Mitochondria and Plastids.
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Kopečná J, Komenda J, Bučinská L, Sobotka R. Long-term acclimation of the cyanobacterium Synechocystis sp. PCC 6803 to high light is accompanied by an enhanced production of chlorophyll that is preferentially channeled to trimeric photosystem I. PLANT PHYSIOLOGY 2012; 160:2239-50. [PMID: 23037506 PMCID: PMC3510144 DOI: 10.1104/pp.112.207274] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 10/02/2012] [Indexed: 05/03/2023]
Abstract
Cyanobacteria acclimate to high-light conditions by adjusting photosystem stoichiometry through a decrease of photosystem I (PSI) abundance in thylakoid membranes. As PSI complexes bind the majority of chlorophyll (Chl) in cyanobacterial cells, it is accepted that the mechanism controlling PSI level/synthesis is tightly associated with the Chl biosynthetic pathway. However, how Chl is distributed to photosystems under different light conditions remains unknown. Using radioactive labeling by (35)S and by (14)C combined with native/two-dimensional electrophoresis, we assessed the synthesis and accumulation of photosynthetic complexes in parallel with the synthesis of Chl in Synechocystis sp. PCC 6803 cells acclimated to different light intensities. Although cells acclimated to higher irradiances (150 and 300 μE m(-2)s(-1)) exhibited markedly reduced PSI content when compared with cells grown at lower irradiances (10 and 40 μE m(-2) s(-1)), they grew much faster and synthesized significantly more Chl, as well as both photosystems. Interestingly, even under high irradiance, almost all labeled de novo Chl was localized in the trimeric PSI, whereas only a weak Chl labeling in photosystem II (PSII) was accompanied by the intensive (35)S protein labeling, which was much stronger than in PSI. These results suggest that PSII subunits are mostly synthesized using recycled Chl molecules previously released during PSII repair-driven protein degradation. In contrast, most of the fresh Chl is utilized for synthesis of PSI complexes likely to maintain a constant level of PSI during cell proliferation.
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Affiliation(s)
- Jana Kopečná
- Institute of Microbiology, Department of Phototrophic Microorganisms, Academy of Sciences, 37981 Trebon, Czech Republic; and Faculty of Science, University of South Bohemia, 370 05 Ceske Budejovice, Czech Republic
| | - Josef Komenda
- Institute of Microbiology, Department of Phototrophic Microorganisms, Academy of Sciences, 37981 Trebon, Czech Republic; and Faculty of Science, University of South Bohemia, 370 05 Ceske Budejovice, Czech Republic
| | - Lenka Bučinská
- Institute of Microbiology, Department of Phototrophic Microorganisms, Academy of Sciences, 37981 Trebon, Czech Republic; and Faculty of Science, University of South Bohemia, 370 05 Ceske Budejovice, Czech Republic
| | - Roman Sobotka
- Institute of Microbiology, Department of Phototrophic Microorganisms, Academy of Sciences, 37981 Trebon, Czech Republic; and Faculty of Science, University of South Bohemia, 370 05 Ceske Budejovice, Czech Republic
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Kuchmina E, Wallner T, Kryazhov S, Zinchenko V, Wilde A. An expression system for regulated protein production in Synechocystis sp. PCC 6803 and its application for construction of a conditional knockout of the ferrochelatase enzyme. J Biotechnol 2012; 162:75-80. [DOI: 10.1016/j.jbiotec.2012.06.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Revised: 05/23/2012] [Accepted: 06/18/2012] [Indexed: 11/17/2022]
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Barajas-López JDD, Blanco NE, Strand Å. Plastid-to-nucleus communication, signals controlling the running of the plant cell. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1833:425-37. [PMID: 22749883 DOI: 10.1016/j.bbamcr.2012.06.020] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 06/14/2012] [Accepted: 06/15/2012] [Indexed: 12/30/2022]
Abstract
The presence of genes encoding organellar proteins in both the nucleus and the organelle necessitates tight coordination of expression by the different genomes, and this has led to the evolution of sophisticated intracellular signaling networks. Organelle-to-nucleus signaling, or retrograde control, coordinates the expression of nuclear genes encoding organellar proteins with the metabolic and developmental state of the organelle. Complex networks of retrograde signals orchestrate major changes in nuclear gene expression and coordinate cellular activities and assist the cell during plant development and stress responses. It has become clear that, even though the chloroplast depends on the nucleus for its function, plastid signals play important roles in an array of different cellular processes vital to the plant. Hence, the chloroplast exerts significant control over the running of the cell. This article is part of a Special Issue entitled: Protein Import and Quality Control in Mitochondria and Plastids.
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Hollingshead S, Kopecná J, Jackson PJ, Canniffe DP, Davison PA, Dickman MJ, Sobotka R, Hunter CN. Conserved chloroplast open-reading frame ycf54 is required for activity of the magnesium protoporphyrin monomethylester oxidative cyclase in Synechocystis PCC 6803. J Biol Chem 2012; 287:27823-33. [PMID: 22711541 DOI: 10.1074/jbc.m112.352526] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The cyclase step in chlorophyll (Chl) biosynthesis has not been characterized biochemically, although there are some plausible candidates for cyclase subunits. Two of these, Sll1214 and Sll1874 from the cyanobacterium Synechocystis 6803, were FLAG-tagged in vivo and used as bait in separate pulldown experiments. Mass spectrometry identified Ycf54 as an interaction partner in each case, and this interaction was confirmed by a reciprocal pulldown using FLAG-tagged Ycf54 as bait. Inactivation of the ycf54 gene (slr1780) in Synechocystis 6803 resulted in a strain that exhibited significantly reduced Chl levels. A detailed analysis of Chl precursors in the ycf54 mutant revealed accumulation of very high levels of Mg-protoporphyrin IX methyl ester and only traces of protochlorophyllide, the product of the cyclase, were detected. Western blotting demonstrated that levels of the cyclase component Sll1214 and the Chl biosynthesis enzymes Mg-protoporphyrin IX methyltransferase and protochlorophyllide reductase are significantly impaired in the ycf54 mutant. Ycf54 is, therefore, essential for the activity and stability of the oxidative cyclase. We discuss a possible role of Ycf54 as an auxiliary factor essential for the assembly of a cyclase complex or even a large multienzyme catalytic center.
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Affiliation(s)
- Sarah Hollingshead
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, United Kingdom
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Tanaka R, Kobayashi K, Masuda T. Tetrapyrrole Metabolism in Arabidopsis thaliana. THE ARABIDOPSIS BOOK 2011; 9:e0145. [PMID: 22303270 PMCID: PMC3268503 DOI: 10.1199/tab.0145] [Citation(s) in RCA: 152] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Higher plants produce four classes of tetrapyrroles, namely, chlorophyll (Chl), heme, siroheme, and phytochromobilin. In plants, tetrapyrroles play essential roles in a wide range of biological activities including photosynthesis, respiration and the assimilation of nitrogen/sulfur. All four classes of tetrapyrroles are derived from a common biosynthetic pathway that resides in the plastid. In this article, we present an overview of tetrapyrrole metabolism in Arabidopsis and other higher plants, and we describe all identified enzymatic steps involved in this metabolism. We also summarize recent findings on Chl biosynthesis and Chl breakdown. Recent advances in this field, in particular those on the genetic and biochemical analyses of novel enzymes, prompted us to redraw the tetrapyrrole metabolic pathways. In addition, we also summarize our current understanding on the regulatory mechanisms governing tetrapyrrole metabolism. The interactions of tetrapyrrole biosynthesis and other cellular processes including the plastid-to-nucleus signal transduction are discussed.
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Affiliation(s)
- Ryouichi Tanaka
- Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan
| | | | - Tatsuru Masuda
- Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
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Heme synthesis by plastid ferrochelatase I regulates nuclear gene expression in plants. Curr Biol 2011; 21:897-903. [PMID: 21565502 PMCID: PMC4886857 DOI: 10.1016/j.cub.2011.04.004] [Citation(s) in RCA: 232] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Revised: 02/14/2011] [Accepted: 04/04/2011] [Indexed: 01/16/2023]
Abstract
Chloroplast signals regulate hundreds of nuclear genes during development and in response to stress, but little is known of the signals or signal transduction mechanisms of plastid-to-nucleus (retrograde) signaling. In Arabidopsis thaliana, genetic studies using norflurazon (NF), an inhibitor of carotenoid biosynthesis, have identified five GUN (genomes uncoupled) genes, implicating the tetrapyrrole pathway as a source of a retrograde signal. Loss of function of any of these GUN genes leads to increased expression of photosynthesis-associated nuclear genes (PhANGs) when chloroplast development has been blocked by NF. Here we present a new Arabidopsis gain-of-function mutant, gun6-1D, with a similar phenotype. The gun6-1D mutant overexpresses the conserved plastid ferrochelatase 1 (FC1, heme synthase). Genetic and biochemical experiments demonstrate that increased flux through the heme branch of the plastid tetrapyrrole biosynthetic pathway increases PhANG expression. The second conserved plant ferrochelatase, FC2, colocalizes with FC1, but FC2 activity is unable to increase PhANG expression in undeveloped plastids. These data suggest a model in which heme, specifically produced by FC1, may be used as a retrograde signal to coordinate PhANG expression with chloroplast development.
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Kořený L, Oborník M. Sequence evidence for the presence of two tetrapyrrole pathways in Euglena gracilis. Genome Biol Evol 2011; 3:359-64. [PMID: 21444293 PMCID: PMC5654406 DOI: 10.1093/gbe/evr029] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/22/2011] [Indexed: 11/16/2022] Open
Abstract
Genes encoding enzymes of the tetrapyrrole biosynthetic pathway were searched within Euglena gracilis EST databases and 454 genome reads and their 5' end regions were sequenced when not available. Phylogenetic analyses and protein localization predictions support the hypothesis concerning the presence of two separated tetrapyrrole pathways in E. gracilis. One of these pathways resembles the heme synthesis in primarily heterotrophic eukaryotes and was presumably present in the host cell prior to secondary endosymbiosis with a green alga. The second pathway is similar to the plastid-localized tetrapyrrole syntheses in plants and photosynthetic algae. It appears to be localized to the secondary plastid, presumably derived from an algal endosymbiont and probably serves only for the production of plastidial heme and chlorophyll. Thus, E. gracilis represents an evolutionary intermediate in a metabolic transformation of a primary heterotroph to a photoautotroph through secondary endosymbiosis. We propose here that the tetrapyrrole pathway serves as a highly informative marker for the evolution of plastids and plays a crucial role in the loss of plastids.
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Affiliation(s)
- Luděk Kořený
- Department of Molecular Biology of Protists, Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Parasitology, České Budějovice, Czech Republic
- Department of Molecular Biology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Miroslav Oborník
- Department of Molecular Biology of Protists, Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Parasitology, České Budějovice, Czech Republic
- Department of Molecular Biology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
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