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Hossain A, Gnanagobal H, Cao T, Chakraborty S, Chukwu-Osazuwa J, Soto-Dávila M, Vasquez I, Santander J. Role of cold shock proteins B and D in Aeromonas salmonicida subsp. salmonicida physiology and virulence in lumpfish ( Cyclopterus lumpus). Infect Immun 2024; 92:e0001124. [PMID: 38920386 PMCID: PMC11320987 DOI: 10.1128/iai.00011-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 06/05/2024] [Indexed: 06/27/2024] Open
Abstract
Cold shock proteins (Csp) are pivotal nucleic acid binding proteins known for their crucial roles in the physiology and virulence of various bacterial pathogens affecting plant, insect, and mammalian hosts. However, their significance in bacterial pathogens of teleost fish remains unexplored. Aeromonas salmonicida subsp. salmonicida (hereafter A. salmonicida) is a psychrotrophic pathogen and the causative agent of furunculosis in marine and freshwater fish. Four csp genes (cspB, cspD, cspA, and cspC) have been identified in the genome of A. salmonicida J223 (wild type). Here, we evaluated the role of DNA binding proteins, CspB and CspD, in A. salmonicida physiology and virulence in lumpfish (Cyclopterus lumpus). A. salmonicida ΔcspB, ΔcspD, and the double ΔcspBΔcspD mutants were constructed and characterized. A. salmonicida ΔcspB and ΔcspBΔcspD mutants showed a faster growth at 28°C, and reduced virulence in lumpfish. A. salmonicida ΔcspD showed a slower growth at 28°C, biofilm formation, lower survival in low temperatures and freezing conditions (-20°C, 0°C, and 4°C), deficient in lipopolysaccharide synthesis, and low virulence in lumpfish. Additionally, ΔcspBΔcspD mutants showed less survival in the presence of bile compared to the wild type. Transcriptome analysis revealed that 200, 37, and 921 genes were differentially expressed in ΔcspB, ΔcspD, and ΔcspBΔcspD, respectively. In ΔcspB and ΔcspBΔcspD virulence genes in the chromosome and virulence plasmid were downregulated. Our analysis indicates that CspB and CspD mostly act as a transcriptional activator, influencing cell division (e.g., treB), virulence factors (e.g., aexT), and ultimately virulence.
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Affiliation(s)
- Ahmed Hossain
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, Ocean Science Center, St. John's, Newfoundland, Canada
| | - Hajarooba Gnanagobal
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, Ocean Science Center, St. John's, Newfoundland, Canada
| | - Trung Cao
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, Ocean Science Center, St. John's, Newfoundland, Canada
| | - Setu Chakraborty
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, Ocean Science Center, St. John's, Newfoundland, Canada
| | - Joy Chukwu-Osazuwa
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, Ocean Science Center, St. John's, Newfoundland, Canada
| | - Manuel Soto-Dávila
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, Ocean Science Center, St. John's, Newfoundland, Canada
| | - Ignacio Vasquez
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, Ocean Science Center, St. John's, Newfoundland, Canada
| | - Javier Santander
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, Ocean Science Center, St. John's, Newfoundland, Canada
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Chen S, Ye M, Kuai P, Chen L, Lou Y. Silencing an ATP-Dependent Caseinolytic Protease Proteolytic Subunit Gene Enhances the Resistance of Rice to Nilaparvata lugens. Int J Mol Sci 2024; 25:3699. [PMID: 38612510 PMCID: PMC11011769 DOI: 10.3390/ijms25073699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 03/21/2024] [Accepted: 03/21/2024] [Indexed: 04/14/2024] Open
Abstract
The ATP-dependent caseinolytic protease (Clp) system has been reported to play an important role in plant growth, development, and defense against pathogens. However, whether the Clp system is involved in plant defense against herbivores remains largely unclear. We explore the role of the Clp system in rice defenses against brown planthopper (BPH) Nilaparvata lugens by combining chemical analysis, transcriptome, and molecular analyses, as well as insect bioassays. We found the expression of a rice Clp proteolytic subunit gene, OsClpP6, was suppressed by infestation of BPH gravid females and mechanical wounding. Silencing OsClpP6 enhanced the level of BPH-induced jasmonic acid (JA), JA-isoleucine (JA-Ile), and ABA, which in turn promoted the production of BPH-elicited rice volatiles and increased the resistance of rice to BPH. Field trials showed that silencing OsClpP6 decreased the population densities of BPH and WBPH. We also observed that silencing OsClpP6 decreased chlorophyll content in rice leaves at early developmental stages and impaired rice root growth and seed setting rate. These findings demonstrate that an OsClpP6-mediated Clp system in rice was involved in plant growth-defense trade-offs by affecting the biosynthesis of defense-related signaling molecules in chloroplasts. Moreover, rice plants, after recognizing BPH infestation, can enhance rice resistance to BPH by decreasing the Clp system activity. The work might provide a new way to breed rice varieties that are resistant to herbivores.
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Affiliation(s)
| | | | | | | | - Yonggen Lou
- State Key Laboratory of Rice Breeding and Biology & Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects, Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China; (S.C.); (M.Y.); (P.K.); (L.C.)
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Ma C, Feng Y, Wang J, Zheng B, Wang X, Jiao N. Integrative Physiological, Transcriptome, and Proteome Analyses Provide Insights into the Photosynthetic Changes in Maize in a Maize-Peanut Intercropping System. PLANTS (BASEL, SWITZERLAND) 2023; 13:65. [PMID: 38202373 PMCID: PMC10780508 DOI: 10.3390/plants13010065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/08/2023] [Accepted: 12/15/2023] [Indexed: 01/12/2024]
Abstract
Intercropping is a traditional and sustainable planting method that can make rational use of natural resources such as light, temperature, fertilizer, water, and CO2. Due to its efficient resource utilization, intercropping, in particular, maize and legume intercropping, is widespread around the world. However, the molecular details of these pathways remain largely unknown. In this study, physiological, transcriptome, and proteome analyses were compared between maize monocropping and maize-peanut intercropping. The results show that an intercropping system enhanced the ability of carbon fixation and carboxylation of maize leaves. Apparent quantum yield (AQY), the light-saturated net photosynthetic rate (LSPn), the light saturation point (LSP), and the light compensation point (LCP) were increased by 11.6%, 9.4%, 8.9%, and 32.1% in the intercropping system, respectively; carboxylation efficiency (CE), the CO2 saturation point (Cisat), the Rubisco maximum carboxylation rate (Vcmax), the maximum electron transfer rate (Jmax), and the triose phosphate utilization rate (TPU) were increased by 28.5%, 7.3%, 18.7%, 29.2%, and 17.0%, respectively; meanwhile, the CO2 compensation point (Γ) decreased by 22.6%. Moreover, the transcriptome analysis confirmed the presence of 588 differentially expressed genes (DEGs), and the numbers of up-regulated and down-regulated genes were 383 and 205, respectively. The DEGs were primarily concerned with ribosomes, plant hormone signal transduction, and photosynthesis. Furthermore, 549 differentially expressed proteins (DEPs) were identified in the maize leaves in both the maize monocropping and maize-peanut intercropping systems. Bioinformatics analysis revealed that 186 DEPs were related to 37 specific KEGG pathways in each of the two treatment groups. Based on the physiological, transcriptome, and proteome analyses, it was demonstrated that the photosynthetic characteristics in maize leaves can be improved by maize-peanut intercropping. This may be related to PS I, PS II, cytochrome b6f complex, ATP synthase, and photosynthetic CO2 fixation, which is caused by the improved CO2 carboxylation efficiency. Our results provide a more in-depth understanding of the high yield and high-efficiency mechanism in maize and peanut intercropping.
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Affiliation(s)
- Chao Ma
- College of Agriculture, Henan University of Science and Technology, Luoyang 471023, China; (C.M.); (J.W.); (B.Z.); (X.W.)
| | - Yalan Feng
- College of Life Science, Wuchang University of Technology, Wuhan 430223, China;
| | - Jiangtao Wang
- College of Agriculture, Henan University of Science and Technology, Luoyang 471023, China; (C.M.); (J.W.); (B.Z.); (X.W.)
| | - Bin Zheng
- College of Agriculture, Henan University of Science and Technology, Luoyang 471023, China; (C.M.); (J.W.); (B.Z.); (X.W.)
| | - Xiaoxiao Wang
- College of Agriculture, Henan University of Science and Technology, Luoyang 471023, China; (C.M.); (J.W.); (B.Z.); (X.W.)
| | - Nianyuan Jiao
- College of Agriculture, Henan University of Science and Technology, Luoyang 471023, China; (C.M.); (J.W.); (B.Z.); (X.W.)
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Dadras A, Fürst-Jansen JMR, Darienko T, Krone D, Scholz P, Sun S, Herrfurth C, Rieseberg TP, Irisarri I, Steinkamp R, Hansen M, Buschmann H, Valerius O, Braus GH, Hoecker U, Feussner I, Mutwil M, Ischebeck T, de Vries S, Lorenz M, de Vries J. Environmental gradients reveal stress hubs pre-dating plant terrestrialization. NATURE PLANTS 2023; 9:1419-1438. [PMID: 37640935 PMCID: PMC10505561 DOI: 10.1038/s41477-023-01491-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 07/11/2023] [Indexed: 08/31/2023]
Abstract
Plant terrestrialization brought forth the land plants (embryophytes). Embryophytes account for most of the biomass on land and evolved from streptophyte algae in a singular event. Recent advances have unravelled the first full genomes of the closest algal relatives of land plants; among the first such species was Mesotaenium endlicherianum. Here we used fine-combed RNA sequencing in tandem with a photophysiological assessment on Mesotaenium exposed to a continuous range of temperature and light cues. Our data establish a grid of 42 different conditions, resulting in 128 transcriptomes and ~1.5 Tbp (~9.9 billion reads) of data to study the combinatory effects of stress response using clustering along gradients. Mesotaenium shares with land plants major hubs in genetic networks underpinning stress response and acclimation. Our data suggest that lipid droplet formation and plastid and cell wall-derived signals have denominated molecular programmes since more than 600 million years of streptophyte evolution-before plants made their first steps on land.
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Affiliation(s)
- Armin Dadras
- Institute of Microbiology and Genetics, Department of Applied Bioinformatics, University of Goettingen, Goettingen, Germany
| | - Janine M R Fürst-Jansen
- Institute of Microbiology and Genetics, Department of Applied Bioinformatics, University of Goettingen, Goettingen, Germany
- Campus Institute Data Science, University of Goettingen, Goettingen, Germany
| | - Tatyana Darienko
- Institute of Microbiology and Genetics, Department of Applied Bioinformatics, University of Goettingen, Goettingen, Germany
| | - Denis Krone
- Institute of Microbiology and Genetics, Department of Applied Bioinformatics, University of Goettingen, Goettingen, Germany
| | - Patricia Scholz
- Albrecht-von-Haller-Institute for Plant Sciences, Department of Plant Biochemistry, University of Goettingen, Goettingen, Germany
| | - Siqi Sun
- Institute of Plant Biology and Biotechnology, Green Biotechnology, University of Münster, Münster, Germany
| | - Cornelia Herrfurth
- Albrecht-von-Haller-Institute for Plant Sciences, Department of Plant Biochemistry, University of Goettingen, Goettingen, Germany
- Goettingen Center for Molecular Biosciences, Service Unit for Metabolomics and Lipidomics, University of Goettingen, Goettingen, Germany
| | - Tim P Rieseberg
- Institute of Microbiology and Genetics, Department of Applied Bioinformatics, University of Goettingen, Goettingen, Germany
| | - Iker Irisarri
- Institute of Microbiology and Genetics, Department of Applied Bioinformatics, University of Goettingen, Goettingen, Germany
- Campus Institute Data Science, University of Goettingen, Goettingen, Germany
- Section Phylogenomics, Centre for Molecular Biodiversity Research, Leibniz Institute for the Analysis of Biodiversity Change, Museum of Nature, Hamburg, Germany
| | - Rasmus Steinkamp
- Institute of Microbiology and Genetics, Department of Applied Bioinformatics, University of Goettingen, Goettingen, Germany
| | - Maike Hansen
- Institute for Plant Sciences and Cluster of Excellence on Plant Sciences, Biocenter, University of Cologne, Cologne, Germany
| | - Henrik Buschmann
- Faculty of Applied Computer Sciences and Biosciences, Section Biotechnology and Chemistry, Molecular Biotechnology, University of Applied Sciences Mittweida, Mittweida, Germany
| | - Oliver Valerius
- Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences and Service Unit LCMS Protein Analytics, Department of Molecular Microbiology and Genetics, University of Goettingen, Goettingen, Germany
| | - Gerhard H Braus
- Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences and Service Unit LCMS Protein Analytics, Department of Molecular Microbiology and Genetics, University of Goettingen, Goettingen, Germany
| | - Ute Hoecker
- Institute for Plant Sciences and Cluster of Excellence on Plant Sciences, Biocenter, University of Cologne, Cologne, Germany
| | - Ivo Feussner
- Albrecht-von-Haller-Institute for Plant Sciences, Department of Plant Biochemistry, University of Goettingen, Goettingen, Germany
- Goettingen Center for Molecular Biosciences, Service Unit for Metabolomics and Lipidomics, University of Goettingen, Goettingen, Germany
- Goettingen Center for Molecular Biosciences, Department of Plant Biochemistry, University of Goettingen, Goettingen, Germany
| | - Marek Mutwil
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Till Ischebeck
- Institute of Plant Biology and Biotechnology, Green Biotechnology, University of Münster, Münster, Germany
| | - Sophie de Vries
- Institute of Microbiology and Genetics, Department of Applied Bioinformatics, University of Goettingen, Goettingen, Germany
| | - Maike Lorenz
- Albrecht-von-Haller-Institute for Plant Sciences, Department of Experimental Phycology and SAG Culture Collection of Algae, University of Goettingen, Goettingen, Germany
| | - Jan de Vries
- Institute of Microbiology and Genetics, Department of Applied Bioinformatics, University of Goettingen, Goettingen, Germany.
- Campus Institute Data Science, University of Goettingen, Goettingen, Germany.
- Goettingen Center for Molecular Biosciences, Department of Applied Bioinformatics, University of Goettingen, Goettingen, Germany.
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5
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Winckler LI, Dissmeyer N. Molecular determinants of protein half-life in chloroplasts with focus on the Clp protease system. Biol Chem 2023; 404:499-511. [PMID: 36972025 DOI: 10.1515/hsz-2022-0320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 03/09/2023] [Indexed: 03/29/2023]
Abstract
Abstract
Proteolysis is an essential process to maintain cellular homeostasis. One pathway that mediates selective protein degradation and which is in principle conserved throughout the kingdoms of life is the N-degron pathway, formerly called the ‘N-end rule’. In the cytosol of eukaryotes and prokaryotes, N-terminal residues can be major determinants of protein stability. While the eukaryotic N-degron pathway depends on the ubiquitin proteasome system, the prokaryotic counterpart is driven by the Clp protease system. Plant chloroplasts also contain such a protease network, which suggests that they might harbor an organelle specific N-degron pathway similar to the prokaryotic one. Recent discoveries indicate that the N-terminal region of proteins affects their stability in chloroplasts and provides support for a Clp-mediated entry point in an N-degron pathway in plastids. This review discusses structure, function and specificity of the chloroplast Clp system, outlines experimental approaches to test for an N-degron pathway in chloroplasts, relates these aspects into general plastid proteostasis and highlights the importance of an understanding of plastid protein turnover.
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Affiliation(s)
- Lioba Inken Winckler
- Department of Plant Physiology and Protein Metabolism Laboratory, University of Osnabruck, Barbarastrasse 11, D-49076 Osnabruck, Germany
- Center of Cellular Nanoanalytics (CellNanOs), Barbarastrasse 11, D-49076 Osnabruck, Germany
- Faculty of Biology, University of Osnabruck, Barbarastrasse 11, D-49076 Osnabruck, Germany
| | - Nico Dissmeyer
- Department of Plant Physiology and Protein Metabolism Laboratory, University of Osnabruck, Barbarastrasse 11, D-49076 Osnabruck, Germany
- Center of Cellular Nanoanalytics (CellNanOs), Barbarastrasse 11, D-49076 Osnabruck, Germany
- Faculty of Biology, University of Osnabruck, Barbarastrasse 11, D-49076 Osnabruck, Germany
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6
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Gao LL, Hong ZH, Wang Y, Wu GZ. Chloroplast proteostasis: A story of birth, life, and death. PLANT COMMUNICATIONS 2023; 4:100424. [PMID: 35964157 PMCID: PMC9860172 DOI: 10.1016/j.xplc.2022.100424] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 08/02/2022] [Accepted: 08/10/2022] [Indexed: 06/02/2023]
Abstract
Protein homeostasis (proteostasis) is a dynamic balance of protein synthesis and degradation. Because of the endosymbiotic origin of chloroplasts and the massive transfer of their genetic information to the nucleus of the host cell, many protein complexes in the chloroplasts are constituted from subunits encoded by both genomes. Hence, the proper function of chloroplasts relies on the coordinated expression of chloroplast- and nucleus-encoded genes. The biogenesis and maintenance of chloroplast proteostasis are dependent on synthesis of chloroplast-encoded proteins, import of nucleus-encoded chloroplast proteins from the cytosol, and clearance of damaged or otherwise undesired "old" proteins. This review focuses on the regulation of chloroplast proteostasis, its interaction with proteostasis of the cytosol, and its retrograde control over nuclear gene expression. We also discuss significant issues and perspectives for future studies and potential applications for improving the photosynthetic performance and stress tolerance of crops.
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Affiliation(s)
- Lin-Lin Gao
- Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China; Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Zheng-Hui Hong
- Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China; Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Yinsong Wang
- Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China; Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Guo-Zhang Wu
- Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China; Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
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7
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Natale R, Coppola M, D'Agostino N, Zhang Y, Fernie AR, Castaldi V, Rao R. In silico and in vitro approaches allow the identification of the Prosystemin molecular network. Comput Struct Biotechnol J 2022; 21:212-223. [PMID: 36544481 PMCID: PMC9755248 DOI: 10.1016/j.csbj.2022.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 12/05/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022] Open
Abstract
Tomato Prosystemin (ProSys), the precursor of Systemin, a small peptidic hormone, is produced at very low concentration in unchallenged plants, while its expression greatly increases in response to several different stressors triggering an array of defence responses. The molecular mechanisms that underpin such a wide array of defence barriers are not fully understood and are likely correlated with the intrinsically disordered (ID) structure of the protein. ID proteins interact with different protein partners forming complexes involved in the modulation of different biological mechanisms. Here we describe the ProSys-protein network that shed light on the molecular mechanisms underpinning ProSys associated defence responses. Three different approaches were used. In silico prediction resulted in 98 direct interactors, most clustering in phytohormone biosynthesis, transcription factors and signal transduction gene classes. The network shows the central role of ProSys during defence responses, that reflects its role as central hub. In vitro ProSys interactors, identified by Affinity Purification-Mass Spectrometry (AP-MS), revealed over three hundred protein partners, while Bimolecular Fluorescent Complementation (BiFC) experiments validated in vivo some interactors predicted in silico and in vitro. Our results demonstrate that ProSys interacts with several proteins and reveal new key molecular events in the ProSys-dependent defence response of tomato plant.
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Affiliation(s)
- Roberto Natale
- Department of Agricultural Sciences, University of Naples Federico II, Portici 80055, Italy
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm 14476, Germany
| | - Mariangela Coppola
- Department of Agricultural Sciences, University of Naples Federico II, Portici 80055, Italy
| | - Nunzio D'Agostino
- Department of Agricultural Sciences, University of Naples Federico II, Portici 80055, Italy
| | - Youjun Zhang
- Center of Plant Systems Biology and Biotechnology, Plovdiv 4000, Bulgaria
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm 14476, Germany
| | - Alisdair Robert Fernie
- Center of Plant Systems Biology and Biotechnology, Plovdiv 4000, Bulgaria
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm 14476, Germany
| | - Valeria Castaldi
- Department of Agricultural Sciences, University of Naples Federico II, Portici 80055, Italy
| | - Rosa Rao
- Department of Agricultural Sciences, University of Naples Federico II, Portici 80055, Italy
- Interuniversity Center for Studies on Bioinspired Agro-Environmental Technology (BAT Center), University of Naples Federico II, Portici 80055, Italy
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8
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Mei X, Zhang K, Lin Y, Su H, Lin C, Chen B, Yang H, Zhang L. Metabolic and Transcriptomic Profiling Reveals Etiolated Mechanism in Huangyu Tea ( Camellia sinensis) Leaves. Int J Mol Sci 2022; 23:ijms232315044. [PMID: 36499369 PMCID: PMC9740216 DOI: 10.3390/ijms232315044] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/26/2022] [Accepted: 11/28/2022] [Indexed: 12/03/2022] Open
Abstract
Leaf color is one of the key factors involved in determining the processing suitability of tea. It relates to differential accumulation of flavor compounds due to the different metabolic mechanisms. In recent years, photosensitive etiolation or albefaction is an interesting direction in tea research field. However, the molecular mechanism of color formation remains unclear since albino or etiolated mutants have different genetic backgrounds. In this study, wide-target metabolomic and transcriptomic analyses were used to reveal the biological mechanism of leaf etiolation for 'Huangyu', a bud mutant of 'Yinghong 9'. The results indicated that the reduction in the content of chlorophyll and the ratio of chlorophyll to carotenoids might be the biochemical reasons for the etiolation of 'Huangyu' tea leaves, while the content of zeaxanthin was significantly higher. The differentially expressed genes (DEGs) involved in chlorophyll and chloroplast biogenesis were the biomolecular reasons for the formation of green or yellow color in tea leaves. In addition, our results also revealed that the changes of DEGs involved in light-induced proteins and circadian rhythm promoted the adaptation of etiolated tea leaves to light stress. Variant colors of tea leaves indicated different directions in metabolic flux and accumulation of flavor compounds.
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Affiliation(s)
- Xin Mei
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Kaikai Zhang
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Yongen Lin
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Hongfeng Su
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Chuyuan Lin
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Baoyi Chen
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Haijun Yang
- Center for Basic Experiments and Practical Training, South China Agricultural University, Guangzhou 510642, China
- Correspondence: (H.Y.); (L.Z.); Tel.: +86-020-8528-0542 (L.Z.)
| | - Lingyun Zhang
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
- Correspondence: (H.Y.); (L.Z.); Tel.: +86-020-8528-0542 (L.Z.)
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9
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Liebers M, Cozzi C, Uecker F, Chambon L, Blanvillain R, Pfannschmidt T. Biogenic signals from plastids and their role in chloroplast development. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:7105-7125. [PMID: 36002302 DOI: 10.1093/jxb/erac344] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 08/23/2022] [Indexed: 06/15/2023]
Abstract
Plant seeds do not contain differentiated chloroplasts. Upon germination, the seedlings thus need to gain photoautotrophy before storage energies are depleted. This requires the coordinated expression of photosynthesis genes encoded in nuclear and plastid genomes. Chloroplast biogenesis needs to be additionally coordinated with the light regulation network that controls seedling development. This coordination is achieved by nucleus to plastid signals called anterograde and plastid to nucleus signals termed retrograde. Retrograde signals sent from plastids during initial chloroplast biogenesis are also called biogenic signals. They have been recognized as highly important for proper chloroplast biogenesis and for seedling development. The molecular nature, transport, targets, and signalling function of biogenic signals are, however, under debate. Several studies disproved the involvement of a number of key components that were at the base of initial models of retrograde signalling. New models now propose major roles for a functional feedback between plastid and cytosolic protein homeostasis in signalling plastid dysfunction as well as the action of dually localized nucleo-plastidic proteins that coordinate chloroplast biogenesis with light-dependent control of seedling development. This review provides a survey of the developments in this research field, summarizes the unsolved questions, highlights several recent advances, and discusses potential new working modes.
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Affiliation(s)
- Monique Liebers
- Gottfried-Wilhelm-Leibniz-Universität Hannover, Naturwissenschaftliche Fakultät, Institut für Botanik, Pflanzenphysiologie, Herrenhäuser Str. 2, D-30419 Hannover, Germany
| | - Carolina Cozzi
- Gottfried-Wilhelm-Leibniz-Universität Hannover, Naturwissenschaftliche Fakultät, Institut für Botanik, Pflanzenphysiologie, Herrenhäuser Str. 2, D-30419 Hannover, Germany
| | - Finia Uecker
- Gottfried-Wilhelm-Leibniz-Universität Hannover, Naturwissenschaftliche Fakultät, Institut für Botanik, Pflanzenphysiologie, Herrenhäuser Str. 2, D-30419 Hannover, Germany
| | - Louise Chambon
- Université Grenoble-Alpes, CNRS, CEA, INRA, IRIG-LPCV, F-38000 Grenoble, France
| | - Robert Blanvillain
- Université Grenoble-Alpes, CNRS, CEA, INRA, IRIG-LPCV, F-38000 Grenoble, France
| | - Thomas Pfannschmidt
- Gottfried-Wilhelm-Leibniz-Universität Hannover, Naturwissenschaftliche Fakultät, Institut für Botanik, Pflanzenphysiologie, Herrenhäuser Str. 2, D-30419 Hannover, Germany
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10
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Williams AM, Carter OG, Forsythe ES, Mendoza HK, Sloan DB. Gene duplication and rate variation in the evolution of plastid ACCase and Clp genes in angiosperms. Mol Phylogenet Evol 2022; 168:107395. [PMID: 35033670 PMCID: PMC9673162 DOI: 10.1016/j.ympev.2022.107395] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 11/16/2021] [Accepted: 12/13/2021] [Indexed: 11/19/2022]
Abstract
While the chloroplast (plastid) is known for its role in photosynthesis, it is also involved in many other metabolic pathways essential for plant survival. As such, plastids contain an extensive suite of enzymes required for non-photosynthetic processes. The evolution of the associated genes has been especially dynamic in flowering plants (angiosperms), including examples of gene duplication and extensive rate variation. We examined the role of ongoing gene duplication in two key plastid enzymes, the acetyl-CoA carboxylase (ACCase) and the caseinolytic protease (Clp), responsible for fatty acid biosynthesis and protein turnover, respectively. In plants, there are two ACCase complexes-a homomeric version present in the cytosol and a heteromeric version present in the plastid. Duplications of the nuclear-encoded homomeric ACCase gene and retargeting of one resultant protein to the plastid have been previously reported in multiple species. We find that these retargeted homomeric ACCase proteins exhibit elevated rates of sequence evolution, consistent with neofunctionalization and/or relaxation of selection. The plastid Clp complex catalytic core is composed of nine paralogous proteins that arose via ancient gene duplication in the cyanobacterial/plastid lineage. We show that further gene duplication occurred more recently in the nuclear-encoded core subunits of this complex, yielding additional paralogs in many species of angiosperms. Moreover, in six of eight cases, subunits that have undergone recent duplication display increased rates of sequence evolution relative to those that have remained single copy. We also compared substitution patterns between pairs of Clp core paralogs to gain insight into post-duplication evolutionary routes. These results show that gene duplication and rate variation continue to shape the plastid proteome.
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Affiliation(s)
- Alissa M Williams
- Department of Biology, Colorado State University, Fort Collins, CO 80523, United States; Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO 80523, United States.
| | - Olivia G Carter
- Department of Biology, Colorado State University, Fort Collins, CO 80523, United States
| | - Evan S Forsythe
- Department of Biology, Colorado State University, Fort Collins, CO 80523, United States
| | - Hannah K Mendoza
- Department of Biology, Colorado State University, Fort Collins, CO 80523, United States
| | - Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, CO 80523, United States
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11
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Abdel-Ghany SE, LaManna LM, Harroun HT, Maliga P, Sloan DB. Rapid sequence evolution is associated with genetic incompatibilities in the plastid Clp complex. PLANT MOLECULAR BIOLOGY 2022; 108:277-287. [PMID: 35039977 DOI: 10.1007/s11103-022-01241-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 12/23/2021] [Indexed: 06/14/2023]
Abstract
KEY MESSAGE Replacing the native clpP1 gene in the Nicotiana plastid genome with homologs from different donor species showed that the extent of genetic incompatibilities depended on the rate of sequence evolution. The plastid caseinolytic protease (Clp) complex plays essential roles in maintaining protein homeostasis and comprises both plastid-encoded and nuclear-encoded subunits. Despite the Clp complex being retained across green plants with highly conserved protein sequences in most species, examples of extremely accelerated amino acid substitution rates have been identified in numerous angiosperms. The causes of these accelerations have been the subject of extensive speculation but still remain unclear. To distinguish among prevailing hypotheses and begin to understand the functional consequences of rapid sequence divergence in Clp subunits, we used plastome transformation to replace the native clpP1 gene in tobacco (Nicotiana tabacum) with counterparts from another angiosperm genus (Silene) that exhibits a wide range in rates of Clp protein sequence evolution. We found that antibiotic-mediated selection could drive a transgenic clpP1 replacement from a slowly evolving donor species (S. latifolia) to homoplasmy but that clpP1 copies from Silene species with accelerated evolutionary rates remained heteroplasmic, meaning that they could not functionally replace the essential tobacco clpP1 gene. These results suggest that observed cases of rapid Clp sequence evolution are a source of epistatic incompatibilities that must be ameliorated by coevolutionary responses between plastid and nuclear subunits.
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Affiliation(s)
- Salah E Abdel-Ghany
- Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA.
| | - Lisa M LaManna
- Waksman Institute of Microbiology, Rutgers University, Piscataway, NJ, 08854, USA
| | - Haleakala T Harroun
- Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Pal Maliga
- Waksman Institute of Microbiology, Rutgers University, Piscataway, NJ, 08854, USA
- Department of Plant Biology, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA.
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12
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Kameniarová M, Černý M, Novák J, Ondrisková V, Hrušková L, Berka M, Vankova R, Brzobohatý B. Light Quality Modulates Plant Cold Response and Freezing Tolerance. FRONTIERS IN PLANT SCIENCE 2022; 13:887103. [PMID: 35755673 PMCID: PMC9221075 DOI: 10.3389/fpls.2022.887103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 05/02/2022] [Indexed: 05/04/2023]
Abstract
The cold acclimation process is regulated by many factors like ambient temperature, day length, light intensity, or hormonal status. Experiments with plants grown under different light quality conditions indicate that the plant response to cold is also a light-quality-dependent process. Here, the role of light quality in the cold response was studied in 1-month-old Arabidopsis thaliana (Col-0) plants exposed for 1 week to 4°C at short-day conditions under white (100 and 20 μmol m-2s-1), blue, or red (20 μmol m-2s-1) light conditions. An upregulated expression of CBF1, inhibition of photosynthesis, and an increase in membrane damage showed that blue light enhanced the effect of low temperature. Interestingly, cold-treated plants under blue and red light showed only limited freezing tolerance compared to white light cold-treated plants. Next, the specificity of the light quality signal in cold response was evaluated in Arabidopsis accessions originating from different and contrasting latitudes. In all but one Arabidopsis accession, blue light increased the effect of cold on photosynthetic parameters and electrolyte leakage. This effect was not found for Ws-0, which lacks functional CRY2 protein, indicating its role in the cold response. Proteomics data confirmed significant differences between red and blue light-treated plants at low temperatures and showed that the cold response is highly accession-specific. In general, blue light increased mainly the cold-stress-related proteins and red light-induced higher expression of chloroplast-related proteins, which correlated with higher photosynthetic parameters in red light cold-treated plants. Altogether, our data suggest that light modulates two distinct mechanisms during the cold treatment - red light-driven cell function maintaining program and blue light-activated specific cold response. The importance of mutual complementarity of these mechanisms was demonstrated by significantly higher freezing tolerance of cold-treated plants under white light.
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Affiliation(s)
- Michaela Kameniarová
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Brno, Czechia
| | - Martin Černý
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Brno, Czechia
| | - Jan Novák
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Brno, Czechia
- *Correspondence: Jan Novák
| | - Vladěna Ondrisková
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Brno, Czechia
| | - Lenka Hrušková
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Brno, Czechia
| | - Miroslav Berka
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Brno, Czechia
| | - Radomira Vankova
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, The Czech Academy of Sciences, Prague, Czechia
| | - Bretislav Brzobohatý
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Brno, Czechia
- Central European Institute of Technology, Faculty of AgriSciences, Mendel University in Brno, Brno, Czechia
- Institute of Biophysics of the Czech Academy of Sciences, Brno, Czechia
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13
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Sharma P, Gayen D. Plant protease as regulator and signaling molecule for enhancing environmental stress-tolerance. PLANT CELL REPORTS 2021; 40:2081-2095. [PMID: 34173047 DOI: 10.1007/s00299-021-02739-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
Proteases are ubiquitous in prokaryotes and eukaryotes. Plant proteases are key regulators of various physiological processes, including protein homeostasis, organelle development, senescence, seed germination, protein processing, environmental stress response, and programmed cell death. Proteases are involved in the breakdown of peptide bonds resulting in irreversible posttranslational modification of the protein. Proteases act as signaling molecules that specifically regulate cellular function by cleaving and triggering receptor molecules. Peptides derived from proteolysis regulate ROS signaling under oxidative stress in the plant. It degrades misfolded and abnormal proteins into amino acids to repair the cell damage and regulates the biological process in response to environmental stress. Proteases modulate the biogenesis of phytohormones which control plant growth, development, and environmental stresses. Protein homeostasis, the overall balance between protein synthesis and proteolysis, is required for plant growth and development. Abiotic and biotic stresses are major factors that negatively impact cellular survivability, biomass production, and reduced crop yield potentials. Therefore, the identification of various stress-responsive proteases and their molecular functions may elucidate valuable information for the development of stress-resilient crops with higher yield potentials. However, the understanding of molecular mechanisms of plant protease remains unexplored. This review provides an overview of proteases related to development, signaling, and growth regulation to acclimatize environmental stress in plants.
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Affiliation(s)
- Punam Sharma
- Department of Biochemistry, Central University of Rajasthan, Ajmer, 305817, Rajasthan, India
| | - Dipak Gayen
- Department of Biochemistry, Central University of Rajasthan, Ajmer, 305817, Rajasthan, India.
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14
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Wang N, Wang Y, Zhao Q, Zhang X, Peng C, Zhang W, Liu Y, Vallon O, Schroda M, Cong Y, Liu C. The cryo-EM structure of the chloroplast ClpP complex. NATURE PLANTS 2021; 7:1505-1515. [PMID: 34782772 DOI: 10.1038/s41477-021-01020-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 10/12/2021] [Indexed: 06/13/2023]
Abstract
Protein homoeostasis in plastids is strategically regulated by the protein quality control system involving multiple chaperones and proteases, among them the Clp protease. Here, we determined the structure of the chloroplast ClpP complex from Chlamydomonas reinhardtii by cryo-electron microscopy. ClpP contains two heptameric catalytic rings without any symmetry. The top ring contains one ClpR6, three ClpP4 and three ClpP5 subunits while the bottom ring is composed of three ClpP1C subunits and one each of the ClpR1-4 subunits. ClpR3, ClpR4 and ClpT4 subunits connect the two rings and stabilize the complex. The chloroplast Cpn11/20/23 co-chaperonin, a co-factor of Cpn60, forms a cap on the top of ClpP by protruding mobile loops into hydrophobic clefts at the surface of the top ring. The co-chaperonin repressed ClpP proteolytic activity in vitro. By regulating Cpn60 chaperone and ClpP protease activity, the co-chaperonin may play a role in coordinating protein folding and degradation in the chloroplast.
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Affiliation(s)
- Ning Wang
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yifan Wang
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
- State Key Laboratory of Molecular Biology, National Center for Protein Science Shanghai, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- Shanghai Science Research Center, Chinese Academy of Sciences, Shanghai, China
| | - Qian Zhao
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Xiang Zhang
- State Key Laboratory of Molecular Biology, National Center for Protein Science Shanghai, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- Shanghai Science Research Center, Chinese Academy of Sciences, Shanghai, China
| | - Chao Peng
- National Facility for Protein Science in Shanghai, Zhangjiang Lab, Shanghai Advanced Research Institute, CAS, Shanghai, China
| | - Wenjuan Zhang
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yanan Liu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Olivier Vallon
- Institut de Biologie Physico-Chimique, Sorbonne Université, Paris, France
| | - Michael Schroda
- Molecular Biotechnology & Systems Biology, TU Kaiserslautern, Kaiserslautern, Germany
| | - Yao Cong
- State Key Laboratory of Molecular Biology, National Center for Protein Science Shanghai, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China.
- Shanghai Science Research Center, Chinese Academy of Sciences, Shanghai, China.
| | - Cuimin Liu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China.
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China.
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15
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The Welwitschia genome reveals a unique biology underpinning extreme longevity in deserts. Nat Commun 2021; 12:4247. [PMID: 34253727 PMCID: PMC8275611 DOI: 10.1038/s41467-021-24528-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 06/21/2021] [Indexed: 02/06/2023] Open
Abstract
The gymnosperm Welwitschia mirabilis belongs to the ancient, enigmatic gnetophyte lineage. It is a unique desert plant with extreme longevity and two ever-elongating leaves. We present a chromosome-level assembly of its genome (6.8 Gb/1 C) together with methylome and transcriptome data to explore its astonishing biology. We also present a refined, high-quality assembly of Gnetum montanum to enhance our understanding of gnetophyte genome evolution. The Welwitschia genome has been shaped by a lineage-specific ancient, whole genome duplication (~86 million years ago) and more recently (1-2 million years) by bursts of retrotransposon activity. High levels of cytosine methylation (particularly at CHH motifs) are associated with retrotransposons, whilst long-term deamination has resulted in an exceptionally GC-poor genome. Changes in copy number and/or expression of gene families and transcription factors (e.g. R2R3MYB, SAUR) controlling cell growth, differentiation and metabolism underpin the plant's longevity and tolerance to temperature, nutrient and water stress.
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16
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Zhao X, Zhang T, Feng H, Qiu T, Li Z, Yang J, Peng YL, Zhao W. OsNBL1, a Multi-Organelle Localized Protein, Plays Essential Roles in Rice Senescence, Disease Resistance, and Salt Tolerance. RICE (NEW YORK, N.Y.) 2021; 14:10. [PMID: 33423130 PMCID: PMC7797018 DOI: 10.1186/s12284-020-00450-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Accepted: 12/26/2020] [Indexed: 06/01/2023]
Abstract
BACKGROUND Plant senescence is a complicated process involving multiple regulations, such as temperature, light, reactive oxygen species (ROS), endogenous hormone levels, and diseases. Although many such genes have been characterized to understand the process of leaf senescence, there still remain many unknowns, and many more genes need to be characterized. RESULTS We identified a rice mutant nbl1 with a premature leaf senescence phenotype. The causative gene, OsNBL1, encodes a small protein with 94 amino acids, which is conserved in monocot, as well as dicot plants. Disruption of OsNBL1 resulted in accelerated dark-induced leaf senescence, accompanied by a reduction in chlorophyll content and up-regulation of several senescence-associated genes. Notably, the nbl1 mutant was more susceptible to rice blast and bacterial blight but more tolerant to sodium chloride. Several salt-induced genes, including HAK1, HAK5, and three SNAC genes, were also up-regulated in the nbl1 mutant. Additionally, the nbl1 mutant was more sensitive to salicylic acid. Plants overexpressing OsNBL1 showed delayed dark-induced senescence, consistent with a higher chlorophyll content compared to wild-type plants. However, the overexpression plants were indistinguishable from the wild-types for resistance to the rice blast disease. OsNBL1 is a multi-organelle localized protein and interacts with OsClpP6, which is associated with senescence. CONCLUSIONS We described a novel leaf senescence mutant nbl1 in rice. It is showed that OsNBL1, a multi-organelle localized protein which interacts with a plastidic caseinolytic protease OsClpP6, is essential for controlling leaf senescence, disease resistance, and salt tolerance.
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Affiliation(s)
- Xiaosheng Zhao
- State Key Laboratory of Agrobiotechnology, MOA Key Lab of Pest Monitoring and Green Management, Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
- Key Laboratory of Crop Heterosis and Utilization, the Ministry of Education/Key Laboratory of Crop Genetic Improvement, Beijing Municipality/ College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Tianbo Zhang
- State Key Laboratory of Agrobiotechnology, MOA Key Lab of Pest Monitoring and Green Management, Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Huijing Feng
- State Key Laboratory of Agrobiotechnology, MOA Key Lab of Pest Monitoring and Green Management, Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Tiancheng Qiu
- State Key Laboratory of Agrobiotechnology, MOA Key Lab of Pest Monitoring and Green Management, Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Zichao Li
- Key Laboratory of Crop Heterosis and Utilization, the Ministry of Education/Key Laboratory of Crop Genetic Improvement, Beijing Municipality/ College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Jun Yang
- State Key Laboratory of Agrobiotechnology, MOA Key Lab of Pest Monitoring and Green Management, Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - You-Liang Peng
- State Key Laboratory of Agrobiotechnology, MOA Key Lab of Pest Monitoring and Green Management, Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Wensheng Zhao
- State Key Laboratory of Agrobiotechnology, MOA Key Lab of Pest Monitoring and Green Management, Department of Plant Pathology, China Agricultural University, Beijing, 100193, China.
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17
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Kim L, Heo J, Kwon DH, Shin JS, Jang SH, Park ZY, Song HK. Structural basis for the N-degron specificity of ClpS1 from Arabidopsis thaliana. Protein Sci 2020; 30:700-708. [PMID: 33368743 DOI: 10.1002/pro.4018] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 12/11/2020] [Accepted: 12/22/2020] [Indexed: 12/25/2022]
Abstract
The N-degron pathway determines the half-life of proteins in both prokaryotes and eukaryotes by precisely recognizing the N-terminal residue (N-degron) of substrates. ClpS proteins from bacteria bind to substrates containing hydrophobic N-degrons (Leu, Phe, Tyr, and Trp) and deliver them to the caseinolytic protease system ClpAP. This mechanism is preserved in organelles such as mitochondria and chloroplasts. Bacterial ClpS adaptors bind preferentially to Leu and Phe N-degrons; however, ClpS1 from Arabidopsis thaliana (AtClpS1) shows a difference in that it binds strongly to Phe and Trp N-degrons and only weakly to Leu. This difference in behavior cannot be explained without structural information due to the high sequence homology between bacterial and plant ClpS proteins. Here, we report the structure of AtClpS1 at 2.0 Å resolution in the presence of a bound N-degron. The key determinants for α-amino group recognition are conserved among all ClpS proteins, but the α3-helix of eukaryotic AtClpS1 is significantly shortened, and consequently, a loop forming a pocket for the N-degron is moved slightly outward to enlarge the pocket. In addition, amino acid replacement from Val to Ala causes a reduction in hydrophobic interactions with Leu N-degron. A combination of the fine-tuned hydrophobic residues in the pocket and the basic gatekeeper at the entrance of the pocket controls the N-degron selectivity of the plant ClpS protein.
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Affiliation(s)
- Leehyeon Kim
- Department of Life Sciences, Korea University, Seoul, South Korea
| | - Jiwon Heo
- Department of Life Sciences, Korea University, Seoul, South Korea
| | - Do Hoon Kwon
- Department of Life Sciences, Korea University, Seoul, South Korea
| | - Jin Seok Shin
- Department of Life Sciences, Korea University, Seoul, South Korea
| | - Se Hwan Jang
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, South Korea
| | - Zee-Yong Park
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, South Korea
| | - Hyun Kyu Song
- Department of Life Sciences, Korea University, Seoul, South Korea
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18
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Recombinant expression, purification and SAXS analysis of Arabidopsis thaliana ClpC1. Int J Biol Macromol 2020; 167:1273-1280. [PMID: 33189753 DOI: 10.1016/j.ijbiomac.2020.11.081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 11/10/2020] [Accepted: 11/11/2020] [Indexed: 11/23/2022]
Abstract
Caseinolytic protease-associated chaperones (Clp chaperones) are HSP100 proteins belonging to the family of ATPases having diverse cellular functions, and they occur in various organisms ranging from bacteria to plants and mammals. Most Clp chaperones have a hexameric organization and associate with tetradecameric Clp proteases to recognize and unfold protein substrates that get degraded within the cellular milieu. Vascular plants have a diverse family of Clp chaperones compared to other organisms; wherein, the chloroplasts of Arabidopsis thaliana alone contain four distinct Clp chaperones, such as ClpC1, ClpC2, ClpD, and ClpB3. The paralogs AtClpC1 and AtClpC2 are more than 90% identical, though the extent of functional overlap between the two is not clear. Moreover, in vitro characterization reports are available only for AtClpC2, as AtClpC1 could not be expressed in recombinant form in the past. Herein, using a bacterial expression system, we have successfully expressed and purified AtClpC1 with a short N-terminal truncation, employing a three-step chromatographic purification strategy. We show that AtClpC1 exists as a hexamer in the presence of ATP and MgCl2, as known for other functional Clp chaperones. Further, our SAXS analyses provide a low-resolution envelope structure for the hexameric AtClpC1, which very well fits a ClpC hexamer model.
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19
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Petereit J, Duncan O, Murcha MW, Fenske R, Cincu E, Cahn J, Pružinská A, Ivanova A, Kollipara L, Wortelkamp S, Sickmann A, Lee J, Lister R, Millar AH, Huang S. Mitochondrial CLPP2 Assists Coordination and Homeostasis of Respiratory Complexes. PLANT PHYSIOLOGY 2020; 184:148-164. [PMID: 32571844 PMCID: PMC7479914 DOI: 10.1104/pp.20.00136] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 06/12/2020] [Indexed: 05/04/2023]
Abstract
Protein homeostasis in eukaryotic organelles and their progenitor prokaryotes is regulated by a series of proteases including the caseinolytic protease (CLPP). CLPP has essential roles in chloroplast biogenesis and maintenance, but the significance of the plant mitochondrial CLPP remains unknown and factors that aid coordination of nuclear- and mitochondrial-encoded subunits for complex assembly in mitochondria await discovery. We generated knockout lines of the single gene for the mitochondrial CLP protease subunit, CLPP2, in Arabidopsis (Arabidopsis thaliana). Mutants showed a higher abundance of transcripts from mitochondrial genes encoding oxidative phosphorylation protein complexes, whereas nuclear genes encoding other subunits of the same complexes showed no change in transcript abundance. By contrast, the protein abundance of specific nuclear-encoded subunits in oxidative phosphorylation complexes I and V increased in CLPP2 knockouts, without accumulation of mitochondrial-encoded counterparts in the same complex. Complexes with subunits mainly or entirely encoded in the nucleus were unaffected. Analysis of protein import and function of complex I revealed that while function was retained, protein homeostasis was disrupted, leading to accumulation of soluble subcomplexes of nuclear-encoded subunits. Therefore, CLPP2 contributes to the mitochondrial protein degradation network through supporting coordination and homeostasis of protein complexes encoded across mitochondrial and nuclear genomes.
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Affiliation(s)
- Jakob Petereit
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Washington 6009, Australia
| | - Owen Duncan
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Washington 6009, Australia
| | - Monika W Murcha
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Washington 6009, Australia
| | - Ricarda Fenske
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Washington 6009, Australia
| | - Emilia Cincu
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Washington 6009, Australia
| | - Jonathan Cahn
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Washington 6009, Australia
| | - Adriana Pružinská
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Washington 6009, Australia
| | - Aneta Ivanova
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Washington 6009, Australia
| | - Laxmikanth Kollipara
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., 44139 Dortmund, Germany
| | - Stefanie Wortelkamp
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., 44139 Dortmund, Germany
| | - Albert Sickmann
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., 44139 Dortmund, Germany
- Department of Chemistry, College of Physical Sciences, University of Aberdeen, Aberdeen AB24 3FX, Scotland, United Kingdom
- Medizinische Fakultät, Medizinische Proteom-Center, Ruhr-Universität Bochum, D-44801 Bochum, Germany
| | - Jiwon Lee
- Centre for advanced Microscopy, The Australian National University, Acton, Australian Capital Territory 2601, Australia
| | - Ryan Lister
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Washington 6009, Australia
- The Harry Perkins Institute of Medical Research, Perth, Washington 6009, Australia
| | - A Harvey Millar
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Washington 6009, Australia
| | - Shaobai Huang
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Washington 6009, Australia
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Ali MS, Baek KH. Co-Suppression of NbClpC1 and NbClpC2, Encoding Clp Protease Chaperons, Elicits Significant Changes in the Metabolic Profile of Nicotiana benthamiana. PLANTS 2020; 9:plants9020259. [PMID: 32085404 PMCID: PMC7076384 DOI: 10.3390/plants9020259] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 02/10/2020] [Accepted: 02/15/2020] [Indexed: 12/30/2022]
Abstract
Metabolites in plants are the products of cellular metabolic processes, and their differential amount can be regarded as the final responses of plants to genetic, epigenetic, or environmental stresses. The Clp protease complex, composed of the chaperonic parts and degradation proteases, is the major degradation system for proteins in plastids. ClpC1 and ClpC2 are the two chaperonic proteins for the Clp protease complex and share more than 90% nucleotide and amino acid sequence similarities. In this study, we employed virus-induced gene silencing to simultaneously suppress the expression of ClpC1 and ClpC2 in Nicotiana benthamiana (NbClpC1/C2). The co-suppression of NbClpC1/C2 in N. benthamiana resulted in aberrant development, with severely chlorotic leaves and stunted growth. A comparison of the control and NbClpC1/C2 co-suppressed N. benthamiana metabolomes revealed a total of 152 metabolites identified by capillary electrophoresis time-of-flight mass spectrometry. The co-suppression of NbClpC1/C2 significantly altered the levels of metabolites in glycolysis, the tricarboxylic acid cycle, the pentose phosphate pathway, and the purine biosynthetic pathway, as well as polyamine and antioxidant metabolites. Our results show that the simultaneous suppression of ClpC1 and ClpC2 leads to aberrant morphological changes in chloroplasts and that these changes are related to changes in the contents of major metabolites acting in cellular metabolism and biosynthetic pathways.
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21
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Filiz E, Aydın Akbudak M. Investigation of PIC1 (permease in chloroplasts 1) gene’s role in iron homeostasis: bioinformatics and expression analyses in tomato and sorghum. Biometals 2019; 33:29-44. [DOI: 10.1007/s10534-019-00228-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Accepted: 11/28/2019] [Indexed: 11/28/2022]
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Rodriguez-Concepcion M, D'Andrea L, Pulido P. Control of plastidial metabolism by the Clp protease complex. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2049-2058. [PMID: 30576524 DOI: 10.1093/jxb/ery441] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 11/29/2018] [Indexed: 05/23/2023]
Abstract
Plant metabolism is strongly dependent on plastids. Besides hosting the photosynthetic machinery, these endosymbiotic organelles synthesize starch, fatty acids, amino acids, nucleotides, tetrapyrroles, and isoprenoids. Virtually all enzymes involved in plastid-localized metabolic pathways are encoded by the nuclear genome and imported into plastids. Once there, protein quality control systems ensure proper folding of the mature forms and remove irreversibly damaged proteins. The Clp protease is the main machinery for protein degradation in the plastid stroma. Recent work has unveiled an increasing number of client proteins of this proteolytic complex in plants. Notably, a substantial proportion of these substrates are required for normal chloroplast metabolism, including enzymes involved in the production of essential tetrapyrroles and isoprenoids such as chlorophylls and carotenoids. The Clp protease complex acts in coordination with nuclear-encoded plastidial chaperones for the control of both enzyme levels and proper folding (i.e. activity). This communication involves a retrograde signaling pathway, similarly to the unfolded protein response previously characterized in mitochondria and endoplasmic reticulum. Coordinated Clp protease and chaperone activities appear to further influence other plastid processes, such as the differentiation of chloroplasts into carotenoid-accumulating chromoplasts during fruit ripening.
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Affiliation(s)
| | - Lucio D'Andrea
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Barcelona, Spain
| | - Pablo Pulido
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Barcelona, Spain
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23
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Zhang S, Zhang H, Xia Y, Xiong L. The caseinolytic protease complex component CLPC1 in Arabidopsis maintains proteome and RNA homeostasis in chloroplasts. BMC PLANT BIOLOGY 2018; 18:192. [PMID: 30208840 PMCID: PMC6136230 DOI: 10.1186/s12870-018-1396-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2018] [Accepted: 08/27/2018] [Indexed: 05/18/2023]
Abstract
BACKGROUND Homeostasis of the proteome is critical to the development of chloroplasts and also affects the expression of certain nuclear genes. CLPC1 facilitates the translocation of chloroplast pre-proteins and mediates protein degradation. RESULTS We found that proteins involved in photosynthesis are dramatically decreased in their abundance in the clpc1 mutant, whereas many proteins involved in chloroplast transcription and translation were increased in the mutant. Expression of the full-length CLPC1 protein, but not of the N-terminus-deleted CLPC1 (ΔN), in the clpc1 mutant background restored the normal levels of most of these proteins. Interestingly, the ΔN complementation line could also restore some proteins affected by the mutation to normal levels. We also found that that the clpc1 mutation profoundly affects transcript levels of chloroplast genes. Sense transcripts of many chloroplast genes are up-regulated in the clpc1 mutant. The level of SVR7, a PPR protein, was affected by the clpc1 mutation. We showed that SVR7 might be a target of CLPC1 as CLPC1-SVR7 interaction was detected through co-immunoprecipitation. CONCLUSION Our study indicates that in addition to its role in maintaining proteome homeostasis, CLPC1 and likely the CLP proteasome complex also play a role in transcriptome homeostasis through its functions in maintaining proteome homeostasis.
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Affiliation(s)
- Shoudong Zhang
- Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China
- Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900 Saudi Arabia
- Centre for Soybean Research, Partner State Key Laboratory of Agrobiotechnology and School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, Special Administrative Region China
| | - Huoming Zhang
- Core labs, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900 Saudi Arabia
| | - Yiji Xia
- Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China
- Partner State Key Laboratory of Environmental and Biological Analysis, Hong Kong Baptist University, Shatin, Hong Kong SAR, China
- Partner State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Shatin, Hong Kong, SAR, China
| | - Liming Xiong
- Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900 Saudi Arabia
- Texas A&M AgriLife Research Center, Dallas, TX 75252 USA
- Department of Horticultural Sciences, Texas A&M University, College Station, TX 77843 USA
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24
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Heer K, Behringer D, Piermattei A, Bässler C, Brandl R, Fady B, Jehl H, Liepelt S, Lorch S, Piotti A, Vendramin G, Weller M, Ziegenhagen B, Büntgen U, Opgenoorth L. Linking dendroecology and association genetics in natural populations: Stress responses archived in tree rings associate with SNP genotypes in silver fir (Abies albaMill.). Mol Ecol 2018; 27:1428-1438. [DOI: 10.1111/mec.14538] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 02/08/2018] [Indexed: 01/07/2023]
Affiliation(s)
- K. Heer
- Faculty of Biology, Conservation Biology; Philipps-University Marburg; Marburg Germany
- Department of Ecology; Faculty of Biology; Philipps-University Marburg; Marburg Germany
| | - D. Behringer
- Faculty of Biology, Conservation Biology; Philipps-University Marburg; Marburg Germany
| | - A. Piermattei
- Department of Geography; University of Cambridge; Cambridge UK
- Department of Agricultural, Food and Environmental Sciences; Marche Polytechnic University; Ancona Italy
- Dendro Science; Swiss Federal Research Institute WSL; Birmensdorf Switzerland
| | - C. Bässler
- Bavarian Forest National Park; Grafenau Germany
| | - R. Brandl
- Department of Ecology; Faculty of Biology; Philipps-University Marburg; Marburg Germany
| | - B. Fady
- INRA; UR Ecologie des Forêts Méditerranéennes; Avignon France
| | - H. Jehl
- Bavarian Forest National Park; Grafenau Germany
| | - S. Liepelt
- Faculty of Biology, Conservation Biology; Philipps-University Marburg; Marburg Germany
| | - S. Lorch
- Department of Ecology; Faculty of Biology; Philipps-University Marburg; Marburg Germany
| | - A. Piotti
- National Research Council; Institute of Biosciences and Bioresources; Firenze Italy
| | - G.G. Vendramin
- National Research Council; Institute of Biosciences and Bioresources; Firenze Italy
| | - M. Weller
- Department of Ecology; Faculty of Biology; Philipps-University Marburg; Marburg Germany
| | - B. Ziegenhagen
- Faculty of Biology, Conservation Biology; Philipps-University Marburg; Marburg Germany
| | - U. Büntgen
- Department of Geography; University of Cambridge; Cambridge UK
- Dendro Science; Swiss Federal Research Institute WSL; Birmensdorf Switzerland
- CzechGlobe, Global Change Research Institute CAS and Masaryk University; Brno Czech Republic
| | - L. Opgenoorth
- Department of Ecology; Faculty of Biology; Philipps-University Marburg; Marburg Germany
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25
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de Oliveira Silva FM, Lichtenstein G, Alseekh S, Rosado-Souza L, Conte M, Suguiyama VF, Lira BS, Fanourakis D, Usadel B, Bhering LL, DaMatta FM, Sulpice R, Araújo WL, Rossi M, de Setta N, Fernie AR, Carrari F, Nunes-Nesi A. The genetic architecture of photosynthesis and plant growth-related traits in tomato. PLANT, CELL & ENVIRONMENT 2018; 41:327-341. [PMID: 29044606 DOI: 10.1111/pce.13084] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 09/22/2017] [Accepted: 09/23/2017] [Indexed: 05/22/2023]
Abstract
To identify genomic regions involved in the regulation of fundamental physiological processes such as photosynthesis and respiration, a population of Solanum pennellii introgression lines was analyzed. We determined phenotypes for physiological, metabolic, and growth related traits, including gas exchange and chlorophyll fluorescence parameters. Data analysis allowed the identification of 208 physiological and metabolic quantitative trait loci with 33 of these being associated to smaller intervals of the genomic regions, termed BINs. Eight BINs were identified that were associated with higher assimilation rates than the recurrent parent M82. Two and 10 genomic regions were related to shoot and root dry matter accumulation, respectively. Nine genomic regions were associated with starch levels, whereas 12 BINs were associated with the levels of other metabolites. Additionally, a comprehensive and detailed annotation of the genomic regions spanning these quantitative trait loci allowed us to identify 87 candidate genes that putatively control the investigated traits. We confirmed 8 of these at the level of variance in gene expression. Taken together, our results allowed the identification of candidate genes that most likely regulate photosynthesis, primary metabolism, and plant growth and as such provide new avenues for crop improvement.
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Affiliation(s)
| | - Gabriel Lichtenstein
- Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaría, and Consejo Nacional de Investigaciones Científicas y Técnicas, B1712WAA, Castelar, Argentina
| | - Saleh Alseekh
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Germany
| | - Laise Rosado-Souza
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Germany
| | - Mariana Conte
- Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaría, and Consejo Nacional de Investigaciones Científicas y Técnicas, B1712WAA, Castelar, Argentina
| | | | - Bruno Silvestre Lira
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, São Paulo, 05508-900, Brazil
| | - Dimitrios Fanourakis
- Department of Viticulture, Floriculture, Vegetable Crops and Plant Protection, GR, 71307, Heraklion, Greece
| | - Björn Usadel
- IBMG: Institute for Biology I, RWTH Aachen University, Worringer Weg 2, 52074, Aachen, Germany
- Forschungszentrum Jülich, IBG-2 Plant Sciences, Wilhelm-Johnen-Straße, 52425, Jülich, Germany
| | - Leonardo Lopes Bhering
- Departamento de Biologia Geral, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Fábio M DaMatta
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Ronan Sulpice
- Plant Systems Biology Lab, Plant and AgriBiosciences Research Centre, Plant & Agribiosiences, National University of Ireland Galway, H91 TK33, Galway, Ireland
| | - Wagner L Araújo
- Max-Planck Partner Group, Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Magdalena Rossi
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, São Paulo, 05508-900, Brazil
| | - Nathalia de Setta
- Universidade Federal do ABC, 09606070, São Bernardo do Campo, São Paulo, Brazil
| | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Germany
| | - Fernando Carrari
- Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaría, and Consejo Nacional de Investigaciones Científicas y Técnicas, B1712WAA, Castelar, Argentina
| | - Adriano Nunes-Nesi
- Max-Planck Partner Group, Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
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26
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Moreno JC, Martínez-Jaime S, Schwartzmann J, Karcher D, Tillich M, Graf A, Bock R. Temporal Proteomics of Inducible RNAi Lines of Clp Protease Subunits Identifies Putative Protease Substrates. PLANT PHYSIOLOGY 2018; 176:1485-1508. [PMID: 29229697 PMCID: PMC5813558 DOI: 10.1104/pp.17.01635] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 12/07/2017] [Indexed: 05/20/2023]
Abstract
The Clp protease in the chloroplasts of plant cells is a large complex composed of at least 13 nucleus-encoded subunits and one plastid-encoded subunit, which are arranged in several ring-like structures. The proteolytic P-ring and the structurally similar R-ring form the core complex that contains the proteolytic chamber. Chaperones of the HSP100 family help with substrate unfolding, and additional accessory proteins are believed to assist with Clp complex assembly and/or to promote complex stability. Although the structure and function of the Clp protease have been studied in great detail in both bacteria and chloroplasts, the identification of bona fide protease substrates has been very challenging. Knockout mutants of genes for protease subunits are of limited value, due to their often pleiotropic phenotypes and the difficulties with distinguishing primary effects (i.e. overaccumulation of proteins that represent genuine protease substrates) from secondary effects (proteins overaccumulating for other reasons). Here, we have developed a new strategy for the identification of candidate substrates of plant proteases. By combining ethanol-inducible knockdown of protease subunits with time-resolved analysis of changes in the proteome, proteins that respond immediately to reduced protease activity can be identified. In this way, secondary effects are minimized and putative protease substrates can be identified. We have applied this strategy to the Clp protease complex of tobacco (Nicotiana tabacum) and identified a set of chloroplast proteins that are likely degraded by Clp. These include several metabolic enzymes but also a small number of proteins involved in photosynthesis.
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Affiliation(s)
- Juan C Moreno
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, D-14476 Potsdam-Golm, Germany
| | - Silvia Martínez-Jaime
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, D-14476 Potsdam-Golm, Germany
| | - Joram Schwartzmann
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, D-14476 Potsdam-Golm, Germany
| | - Daniel Karcher
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, D-14476 Potsdam-Golm, Germany
| | - Michael Tillich
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, D-14476 Potsdam-Golm, Germany
| | - Alexander Graf
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, D-14476 Potsdam-Golm, Germany
| | - Ralph Bock
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, D-14476 Potsdam-Golm, Germany
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27
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Hajrah NH, Obaid AY, Atef A, Ramadan AM, Arasappan D, Nelson CA, Edris S, Mutwakil MZ, Alhebshi A, Gadalla NO, Makki RM, Al-Kordy MA, El-Domyati FM, Sabir JSM, Khiyami MA, Hall N, Bahieldin A, Jansen RK. Transcriptomic analysis of salt stress responsive genes in Rhazya stricta. PLoS One 2017; 12:e0177589. [PMID: 28520766 PMCID: PMC5433744 DOI: 10.1371/journal.pone.0177589] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 04/29/2017] [Indexed: 11/24/2022] Open
Abstract
Rhazya stricta is an evergreen shrub that is widely distributed across Western and South Asia, and like many other members of the Apocynaceae produces monoterpene indole alkaloids that have anti-cancer properties. This species is adapted to very harsh desert conditions making it an excellent system for studying tolerance to high temperatures and salinity. RNA-Seq analysis was performed on R. stricta exposed to severe salt stress (500 mM NaCl) across four time intervals (0, 2, 12 and 24 h) to examine mechanisms of salt tolerance. A large number of transcripts including genes encoding tetrapyrroles and pentatricopeptide repeat (PPR) proteins were regulated only after 12 h of stress of seedlings grown in controlled greenhouse conditions. Mechanisms of salt tolerance in R. stricta may involve the upregulation of genes encoding chaperone protein Dnaj6, UDP-glucosyl transferase 85a2, protein transparent testa 12 and respiratory burst oxidase homolog protein b. Many of the highly-expressed genes act on protecting protein folding during salt stress and the production of flavonoids, key secondary metabolites in stress tolerance. Other regulated genes encode enzymes in the porphyrin and chlorophyll metabolic pathway with important roles during plant growth, photosynthesis, hormone signaling and abiotic responses. Heme biosynthesis in R. stricta leaves might add to the level of salt stress tolerance by maintaining appropriate levels of photosynthesis and normal plant growth as well as by the participation in reactive oxygen species (ROS) production under stress. We speculate that the high expression levels of PPR genes may be dependent on expression levels of their targeted editing genes. Although the results of PPR gene family indicated regulation of a large number of transcripts under salt stress, PPR actions were independent of the salt stress because their RNA editing patterns were unchanged.
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Affiliation(s)
- Nahid H. Hajrah
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
| | - Abdullah Y. Obaid
- Department of Chemistry, Faculty of Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
| | - Ahmed Atef
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
| | - Ahmed M. Ramadan
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
- Agricultural Genetic Engineering Research Institute (AGERI), Agriculture Research Center (ARC), Giza, Egypt
| | - Dhivya Arasappan
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas, United States of America
| | - Charllotte A. Nelson
- Centre of Genomic Research, Institute for Integrative Biology, Crown Street, Liverpool, United Kingdom
| | - Sherif Edris
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
- Department of Genetics, Faculty of Agriculture, Ain Shams University, Cairo, Egypt
- Princess Al-Jawhara Al-Brahim Centre of Excellence in Research of Hereditary Disorders (PACER-HD), Faculty of Medicine, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
| | - Mohammed Z. Mutwakil
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
| | - Alawia Alhebshi
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
| | - Nour O. Gadalla
- Department of Arid Land Agriculture, Faculty of Meteorology, Environment and Arid Land Agriculture, King Abdulaziz University, Jeddah, Saudi Arabia
- Genetics and Cytology Department, Genetic Engineering and Biotechnology Division, National Research Center, Dokki, Egypt
| | - Rania M. Makki
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
| | - Madgy A. Al-Kordy
- Genetics and Cytology Department, Genetic Engineering and Biotechnology Division, National Research Center, Dokki, Egypt
| | - Fotouh M. El-Domyati
- Department of Genetics, Faculty of Agriculture, Ain Shams University, Cairo, Egypt
| | - Jamal S. M. Sabir
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
| | - Mohammad A. Khiyami
- King Abdulaziz City for Science and Technology (KACST), Riyadh, Saudi Arabia
| | - Neil Hall
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
- The Earlham Institute, Norwich Research Park, Norwich, United Kingdom
| | - Ahmed Bahieldin
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
- Department of Genetics, Faculty of Agriculture, Ain Shams University, Cairo, Egypt
| | - Robert K. Jansen
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas, United States of America
- * E-mail:
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28
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Moreno JC, Tiller N, Diez M, Karcher D, Tillich M, Schöttler MA, Bock R. Generation and characterization of a collection of knock-down lines for the chloroplast Clp protease complex in tobacco. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:2199-2218. [PMID: 28369470 PMCID: PMC5447895 DOI: 10.1093/jxb/erx066] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Protein degradation in chloroplasts is carried out by a set of proteases that eliminate misfolded, damaged, or superfluous proteins. The ATP-dependent caseinolytic protease (Clp) is the most complex protease in plastids and has been implicated mainly in stromal protein degradation. In contrast, FtsH, a thylakoid membrane-associated metalloprotease, is believed to participate mainly in the degradation of thylakoidal proteins. To determine the role of specific Clp and FtsH subunits in plant growth and development, RNAi lines targeting at least one subunit of each Clp ring and FtsH were generated in tobacco. In addition, mutation of the translation initiation codon was employed to down-regulate expression of the plastid-encoded ClpP1 subunit. These protease lines cover a broad range of reductions at the transcript and protein levels of the targeted genes. A wide spectrum of phenotypes was obtained, including pigment deficiency, alterations in leaf development, leaf variegations, and impaired photosynthesis. When knock-down lines for the different protease subunits were compared, both common and specific phenotypes were observed, suggesting distinct functions of at least some subunits. Our work provides a well-characterized collection of knock-down lines for plastid proteases in tobacco and reveals the importance of the Clp protease in physiology and plant development.
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Affiliation(s)
- Juan C Moreno
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Nadine Tiller
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Mercedes Diez
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Daniel Karcher
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Michael Tillich
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Mark A Schöttler
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Ralph Bock
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
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29
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Nishimura K, Kato Y, Sakamoto W. Essentials of Proteolytic Machineries in Chloroplasts. MOLECULAR PLANT 2017; 10:4-19. [PMID: 27585878 DOI: 10.1016/j.molp.2016.08.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 08/17/2016] [Accepted: 08/21/2016] [Indexed: 05/22/2023]
Abstract
Plastids are unique organelles that can alter their structure and function in response to environmental and developmental stimuli. Chloroplasts are one type of plastid and are the sites for various metabolic processes, including photosynthesis. For optimal photosynthetic activity, the chloroplast proteome must be properly shaped and maintained through regulated proteolysis and protein quality control mechanisms. Enzymatic functions and activities are conferred by protein maturation processes involving consecutive proteolytic reactions. Protein abundances are optimized by the balanced protein synthesis and degradation, which is depending on the metabolic status. Malfunctioning proteins are promptly degraded. Twenty chloroplast proteolytic machineries have been characterized to date. Specifically, processing peptidases and energy-driven processive proteases are the major players in chloroplast proteome biogenesis, remodeling, and maintenance. Recently identified putative proteases are potential regulators of photosynthetic functions. Here we provide an updated, comprehensive overview of chloroplast protein degradation machineries and discuss their importance for photosynthesis. Wherever possible, we also provide structural insights into chloroplast proteases that implement regulated proteolysis of substrate proteins/peptides.
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Affiliation(s)
- Kenji Nishimura
- Institute of Plant Science and Resources, Okayama University, 2-20-1 Chuo, Kurashiki, Okayama 710-0046, Japan
| | - Yusuke Kato
- Institute of Plant Science and Resources, Okayama University, 2-20-1 Chuo, Kurashiki, Okayama 710-0046, Japan
| | - Wataru Sakamoto
- Institute of Plant Science and Resources, Okayama University, 2-20-1 Chuo, Kurashiki, Okayama 710-0046, Japan.
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30
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Merewitz E, Xu Y, Huang B. Differentially Expressed Genes Associated with Improved Drought Tolerance in Creeping Bentgrass Overexpressing a Gene for Cytokinin Biosynthesis. PLoS One 2016; 11:e0166676. [PMID: 27855226 PMCID: PMC5113972 DOI: 10.1371/journal.pone.0166676] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 11/02/2016] [Indexed: 12/03/2022] Open
Abstract
Transformation with an isopentenyl transferase (ipt) gene controlling cytokinin (CK) synthesis has been shown to enhance plant drought tolerance. The objective of this study was to identify differentially-expressed genes (DEGs) in creeping bentgrass (Agrostis stolonifera) overexpressing ipt compared to non-transgenic plants. The ipt transgene was controlled by a senescence-activated promoter (SAG12). Both a null transformed line (NT) and SAG12-ipt plants were exposed to drought stress in an environmentally-controlled growth chamber until the soil water content declined to approximately 5% and leaf relative water content declined to 47%, which were both significantly below the well-watered controls. RNA was extracted from leaf samples of both well-watered and drought-stressed plants. Eight sets of subtractive hybridizations were performed for detection of up-regulated and down-regulated genes due to the presence of the transgene and due to drought stress in both NT and transgenic plants. Sequencing analysis revealed the identity of 252 DEGs due to either the transgene and drought stress. Sequencing analysis of 170 DEGs identified genes encoding for proteins that were related to energy production, metabolism, stress defense, signaling, protein synthesis and transport, and membrane transport could play major roles in the improved drought tolerance by overexpressing ipt in creeping bentgrass.
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Affiliation(s)
- Emily Merewitz
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, 48824, United States of America
| | - Yi Xu
- Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ, 08901, United States of America
| | - Bingru Huang
- Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ, 08901, United States of America
- * E-mail:
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Wagner R, von Sydow L, Aigner H, Netotea S, Brugière S, Sjögren L, Ferro M, Clarke A, Funk C. Deletion of FtsH11 protease has impact on chloroplast structure and function in Arabidopsis thaliana when grown under continuous light. PLANT, CELL & ENVIRONMENT 2016; 39:2530-2544. [PMID: 27479913 DOI: 10.1111/pce.12808] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 07/12/2016] [Accepted: 07/17/2016] [Indexed: 05/20/2023]
Abstract
The membrane-integrated metalloprotease FtsH11 of Arabidopsis thaliana is proposed to be dual-targeted to mitochondria and chloroplasts. A bleached phenotype was observed in ftsh11 grown at long days or continuous light, pointing to disturbances in the chloroplast. Within the chloroplast, FtsH11 was found to be located exclusively in the envelope. Two chloroplast-located proteins of unknown function (Tic22-like protein and YGGT-A) showed significantly higher abundance in envelope membranes and intact chloroplasts of ftsh11 and therefore qualify as potential substrates for the FtsH11 protease. No proteomic changes were observed in the mitochondria of 6-week-old ftsh11 compared with wild type, and FtsH11 was not immunodetected in these organelles. The abundance of plastidic proteins, especially of photosynthetic proteins, was altered even during standard growth conditions in total leaves of ftsh11. At continuous light, the amount of photosystem I decreased relative to photosystem II, accompanied by a drastic change of the chloroplast morphology and a drop of non-photochemical quenching. FtsH11 is crucial for chloroplast structure and function during growth in prolonged photoperiod.
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Affiliation(s)
- Raik Wagner
- Department of Chemistry, Umeå University, SE-901 87, Umeå, Sweden
| | - Lotta von Sydow
- Department of Chemistry, Umeå University, SE-901 87, Umeå, Sweden
| | - Harald Aigner
- Department of Chemistry, Umeå University, SE-901 87, Umeå, Sweden
| | - Sergiu Netotea
- Department of Chemistry, Umeå University, SE-901 87, Umeå, Sweden
- Bioinformatics Infrastructure for Life Sciences (BILS), Linköping, Sweden
| | - Sabine Brugière
- U1038 INSERM/CEA/UJ, Institut de Recherches en Technologies et Sciences pour le Vivant, Grenoble, Cedex 9, France
| | - Lars Sjögren
- Department of Biological and Environmental Sciences, Gothenburg University, 40530, Gothenburg, Sweden
| | - Myriam Ferro
- U1038 INSERM/CEA/UJ, Institut de Recherches en Technologies et Sciences pour le Vivant, Grenoble, Cedex 9, France
| | - Adrian Clarke
- Department of Biological and Environmental Sciences, Gothenburg University, 40530, Gothenburg, Sweden
| | - Christiane Funk
- Department of Chemistry, Umeå University, SE-901 87, Umeå, Sweden.
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Carlotto N, Wirth S, Furman N, Ferreyra Solari N, Ariel F, Crespi M, Kobayashi K. The chloroplastic DEVH-box RNA helicase INCREASED SIZE EXCLUSION LIMIT 2 involved in plasmodesmata regulation is required for group II intron splicing. PLANT, CELL & ENVIRONMENT 2016; 39:165-73. [PMID: 26147377 DOI: 10.1111/pce.12603] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 06/23/2015] [Accepted: 06/24/2015] [Indexed: 05/18/2023]
Abstract
INCREASED SIZE EXCLUSION LIMIT 2 (ISE2) encodes a putative DEVH-box RNA helicase originally identified through a genetic screening for Arabidopsis mutants altered in plasmodesmata (PD) aperture. Depletion of ISE2 also affects chloroplasts activity, decreases accumulation of photosynthetic pigments and alters expression of photosynthetic genes. In this work, we show the chloroplast localization of ISE2 and decipher its role in plastidic RNA processing and, consequently, PD function. Group II intron-containing RNAs from chloroplasts exhibit defective splicing in ise2 mutants and ISE2-silenced plants, compromising plastid viability. Furthermore, RNA immunoprecipitation suggests that ISE2 binds in vivo to several splicing-regulated RNAs. Finally, we show that the chloroplast clpr2 mutant (defective in a subunit of a plastidic Clp protease) also exhibits abnormal PD function during embryogenesis, supporting the idea that chloroplast RNA processing is required to regulate cell-cell communication in plants.
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Affiliation(s)
- Nicolas Carlotto
- Laboratorio de Agrobiotecnología, Instituto de Biodiversidad y Biología Experimental Aplicada (IBBEA-CONICET-UBA), Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Sonia Wirth
- Laboratorio de Agrobiotecnología, Instituto de Biodiversidad y Biología Experimental Aplicada (IBBEA-CONICET-UBA), Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Nicolas Furman
- Laboratorio de Agrobiotecnología, Instituto de Biodiversidad y Biología Experimental Aplicada (IBBEA-CONICET-UBA), Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Nazarena Ferreyra Solari
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA) - CONICET - Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Federico Ariel
- Institute of Plant Sciences Paris-Saclay (IPS2), UMR 9213/UMR1403, CNRS, INRA, Université Paris-Sud, Université d'Evry, Université Paris-Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405, Orsay, France
| | - Martin Crespi
- Institute of Plant Sciences Paris-Saclay (IPS2), UMR 9213/UMR1403, CNRS, INRA, Université Paris-Sud, Université d'Evry, Université Paris-Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405, Orsay, France
| | - Ken Kobayashi
- Laboratorio de Agrobiotecnología, Instituto de Biodiversidad y Biología Experimental Aplicada (IBBEA-CONICET-UBA), Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
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Flores-Pérez Ú, Bédard J, Tanabe N, Lymperopoulos P, Clarke AK, Jarvis P. Functional Analysis of the Hsp93/ClpC Chaperone at the Chloroplast Envelope. PLANT PHYSIOLOGY 2016; 170:147-62. [PMID: 26586836 PMCID: PMC4704595 DOI: 10.1104/pp.15.01538] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 11/16/2015] [Indexed: 05/20/2023]
Abstract
The Hsp100-type chaperone Hsp93/ClpC has crucial roles in chloroplast biogenesis. In addition to its role in proteolysis in the stroma, biochemical and genetic evidence led to the hypothesis that this chaperone collaborates with the inner envelope TIC complex to power preprotein import. Recently, it was suggested that Hsp93, working together with the Clp proteolytic core, can confer a protein quality control mechanism at the envelope. Thus, the role of envelope-localized Hsp93, and the mechanism by which it participates in protein import, remain unclear. To analyze the function of Hsp93 in protein import independently of its ClpP association, we created a mutant of Hsp93 affecting its ClpP-binding motif (PBM) (Hsp93[P-]), which is essential for the chaperone's interaction with the Clp proteolytic core. The Hsp93[P-] construct was ineffective at complementing the pale-yellow phenotype of hsp93 Arabidopsis (Arabidopsis thaliana) mutants, indicating that the PBM is essential for Hsp93 function. As expected, the PBM mutation negatively affected the degradation activity of the stromal Clp protease. The mutation also disrupted association of Hsp93 with the Clp proteolytic core at the envelope, without affecting the envelope localization of Hsp93 itself or its association with the TIC machinery, which we demonstrate to be mediated by a direct interaction with Tic110. Nonetheless, Hsp93[P-] expression did not detectably improve the protein import efficiency of hsp93 mutant chloroplasts. Thus, our results do not support the proposed function of Hsp93 in protein import propulsion, but are more consistent with the notion of Hsp93 performing a quality control role at the point of import.
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Affiliation(s)
- Úrsula Flores-Pérez
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom (U.F.-P., J.B., P.J.) and Department of Biological and Environmental Sciences, Gothenburg University, 405 30 Gothenburg, Sweden (N.T., P.L., A.K.C.)
| | - Jocelyn Bédard
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom (U.F.-P., J.B., P.J.) and Department of Biological and Environmental Sciences, Gothenburg University, 405 30 Gothenburg, Sweden (N.T., P.L., A.K.C.)
| | - Noriaki Tanabe
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom (U.F.-P., J.B., P.J.) and Department of Biological and Environmental Sciences, Gothenburg University, 405 30 Gothenburg, Sweden (N.T., P.L., A.K.C.)
| | - Panagiotis Lymperopoulos
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom (U.F.-P., J.B., P.J.) and Department of Biological and Environmental Sciences, Gothenburg University, 405 30 Gothenburg, Sweden (N.T., P.L., A.K.C.)
| | - Adrian K Clarke
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom (U.F.-P., J.B., P.J.) and Department of Biological and Environmental Sciences, Gothenburg University, 405 30 Gothenburg, Sweden (N.T., P.L., A.K.C.)
| | - Paul Jarvis
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom (U.F.-P., J.B., P.J.) and Department of Biological and Environmental Sciences, Gothenburg University, 405 30 Gothenburg, Sweden (N.T., P.L., A.K.C.)
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Wei J, Qiu X, Chen L, Hu W, Hu R, Chen J, Sun L, Li L, Zhang H, Lv Z, Shen G. The E3 ligase AtCHIP positively regulates Clp proteolytic subunit homeostasis. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:5809-20. [PMID: 26085677 DOI: 10.1093/jxb/erv286] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The caseinolytic peptidase (Clp) core proteins are essential for plant growth and development, especially for chloroplast function. Antisense or overexpression of ClpP4, which is one of the Clp core subunits, causes chlorotic phenotypes in Arabidopsis. An E3 ligase gene, AtCHIP, has previously been found to ubiquitylate ClpP4 in vitro. ClpP4 antisense and overexpressing plants that also overexpressed AtCHIP were constructed to explore the effect of AtCHIP on ClpP4. Overexpression of AtCHIP was found to rescue the chlorotic phenotypes of both ClpP4 antisense and overexpressing plants. The unbalanced levels of Clp core proteins in ClpP4 antisense and overexpressing plants with overexpression of AtCHIP were similar to wild-type levels, suggesting that AtCHIP regulates Clp core proteins. The results also show that AtCHIP can interact with ClpP3 and ClpP5 in yeast and ubiquitylate ClpP3 and ClpP5 in vitro. This suggests that AtCHIP is directly related to ClpP3 and ClpP5. Given these results, the inference is that through selective degradation of Clp subunits, AtCHIP could positively regulate homeostasis of Clp proteolytic subunits and maximize the production of functional chloroplasts. Similar results were obtained from transgenic tobacco plants, suggesting that regulation of the Clp protease by AtCHIP is conserved.
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Affiliation(s)
- Jia Wei
- Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, Zhejiang Province, China
| | - Xiaoyun Qiu
- Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, Zhejiang Province, China
| | - Lin Chen
- Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, Zhejiang Province, China
| | - Wenjun Hu
- Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, Zhejiang Province, China
| | - Rongbin Hu
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA
| | - Jian Chen
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA
| | - Li Sun
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA
| | - Li Li
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, New York 14853, USA and Department of Plant Breeding and Genetics, Cornell University, Ithaca, New York 14853, USA
| | - Hong Zhang
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA
| | - Zhiqiang Lv
- Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, Zhejiang Province, China
| | - Guoxin Shen
- Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, Zhejiang Province, China
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35
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Ali MS, Kim KW, Dhakal R, Choi D, Baek KH. Accumulation of high contents of free amino acids in the leaves of Nicotiana benthamiana by the co-suppression of NbClpC1 and NbClpC2 genes. PLANT CELL REPORTS 2015; 34:355-65. [PMID: 25433858 DOI: 10.1007/s00299-014-1714-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 10/29/2014] [Accepted: 11/20/2014] [Indexed: 05/27/2023]
Abstract
KEY MESSAGE We report the significant increase of the content of free amino acids in Nicotiana benthamiana by the co-suppression of the ClpC1 and ClpC2 genes, which are translated to be the chaperonic part in the Clp protease at plastids. Clp protease with ClpC1 and ClpC2 proteins as the chaperonic part degrades denatured or improperly folded protein in plastids. Nicotiana benthamiana ClpC1 and ClpC2 genes (NbClpC1 and NbClpC2: NbClpC1/C2) share 93% similarities; therefore, co-suppression of the NbClpC1/C2 was possible using a single virus-induced silencing vector. Co-suppression of NbClpC1/C2 resulted in a pleiotropic phenotype including disappearance of apical dominance and formation of chlorotic leaves. NbClpC1/C2 co-suppressed leaves accumulated 11.9-fold more free amino acids than the GFP-silenced leaves. The co-suppression of NbClpC1/C2 did not change the expression levels of some selected genes in the biosynthetic pathways for the free amino acids, but reduced the total protein amounts to 32.5%, indicating that co-suppression affected the incorporation of free amino acids in proteins during translation. The loosely packed mesophyll cells and abnormal vascular bundles in the leaves suggested structural problems associated with translocation of free amino acids to sink tissues. NbClpC1/C2 co-suppression can offer a novel strategy for accumulation of free amino acids though it results in stunted growth.
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Affiliation(s)
- Md Sarafat Ali
- School of Biotechnology, Yeungnam University, Gyeongsan, Gyeongbuk, 712-749, Korea
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Organization, function and substrates of the essential Clp protease system in plastids. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1847:915-30. [PMID: 25482260 DOI: 10.1016/j.bbabio.2014.11.012] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 11/20/2014] [Indexed: 01/21/2023]
Abstract
Intra-plastid proteolysis is essential in plastid biogenesis, differentiation and plastid protein homeostasis (proteostasis). We provide a comprehensive review of the Clp protease system present in all plastid types and we draw lessons from structural and functional information of bacterial Clp systems. The Clp system plays a central role in plastid development and function, through selective removal of miss-folded, aggregated, or otherwise unwanted proteins. The Clp system consists of a tetradecameric proteolytic core with catalytically active ClpP and inactive ClpR subunits, hexameric ATP-dependent chaperones (ClpC,D) and adaptor protein(s) (ClpS1) enhancing delivery of subsets of substrates. Many structural and functional features of the plastid Clp system are now understood though extensive reverse genetics analysis combined with biochemical analysis, as well as large scale quantitative proteomics for loss-of-function mutants of Clp core, chaperone and ClpS1 subunits. Evolutionary diversification of Clp system across non-photosynthetic and photosynthetic prokaryotes and organelles is illustrated. Multiple substrates have been suggested based on their direct interaction with the ClpS1 adaptor or screening of different loss-of-function protease mutants. The main challenge is now to determine degradation signals (degrons) in Clp substrates and substrate delivery mechanisms, as well as functional interactions of Clp with other plastid proteases. This article is part of a Special Issue entitled: Chloroplast Biogenesis.
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Rochaix JD, Ramundo S. Conditional repression of essential chloroplast genes: Evidence for new plastid signaling pathways. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1847:986-92. [PMID: 25486627 DOI: 10.1016/j.bbabio.2014.11.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 11/26/2014] [Indexed: 01/28/2023]
Abstract
The development of a repressible chloroplast gene expression system in Chlamydomonas reinhardtii has opened the door for studying the role of essential chloroplast genes. This approach has been used to analyze three chloroplast genes of this sort coding for the α subunit of RNA polymerase (rpoA), a ribosomal protein (rps12) and the catalytic subunit of the ATP-dependent ClpP protease (clpP1). Depletion of the three corresponding proteins leads to growth arrest and cell death. Shutdown of chloroplast transcription and translation increases the abundance of a set of plastid transcripts that includes mainly those involved in transcription, translation and proteolysis and reveals multiple regulatory feedback loops in the chloroplast gene circuitry. Depletion of ClpP profoundly affects plastid protein homeostasis and elicits an autophagy-like response with extensive cytoplasmic vacuolization of cells. It also triggers changes in chloroplast and nuclear gene expression resulting in increased abundance of chaperones, proteases, ubiquitin-related proteins and proteins involved in lipid trafficking and thylakoid biogenesis. These features are hallmarks of an unfolded protein response in the chloroplast and raise new questions on plastid protein homeostasis and plastid signaling. This article is part of a Special Issue entitled: Chloroplast Biogenesis.
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Affiliation(s)
- Jean-David Rochaix
- Department of Molecular Biology, University of Geneva, 1211 Geneva, Switzerland; Department of Plant Biology, University of Geneva, 1211 Geneva, Switzerland.
| | - Silvia Ramundo
- Department of Molecular Biology, University of Geneva, 1211 Geneva, Switzerland; Department of Plant Biology, University of Geneva, 1211 Geneva, Switzerland
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Colombo CV, Ceccarelli EA, Rosano GL. Characterization of the accessory protein ClpT1 from Arabidopsis thaliana: oligomerization status and interaction with Hsp100 chaperones. BMC PLANT BIOLOGY 2014; 14:228. [PMID: 25149061 PMCID: PMC4243950 DOI: 10.1186/s12870-014-0228-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 08/18/2014] [Indexed: 05/26/2023]
Abstract
BACKGROUND The caseinolytic protease (Clp) is crucial for chloroplast biogenesis and proteostasis. The Arabidopsis Clp consists of two heptameric rings (P and R rings) assembled from nine distinct subunits. Hsp100 chaperones (ClpC1/2 and ClpD) are believed to dock to the axial pores of Clp and then transfer unfolded polypeptides destined to degradation. The adaptor proteins ClpT1 and 2 attach to the protease, apparently blocking the chaperone binding sites. This competition was suggested to regulate Clp activity. Also, monomerization of ClpT1 from dimers in the stroma triggers P and R rings association. So, oligomerization status of ClpT1 seems to control the assembly of the Clp protease. RESULTS In this work, ClpT1 was obtained in a recombinant form and purified. In solution, it mostly consists of monomers while dimers represent a small fraction of the population. Enrichment of the dimer fraction could only be achieved by stabilization with a crosslinker reagent. We demonstrate that ClpT1 specifically interacts with the Hsp100 chaperones ClpC2 and ClpD. In addition, ClpT1 stimulates the ATPase activity of ClpD by more than 50% when both are present in a 1:1 molar ratio. Outside this optimal proportion, the stimulatory effect of ClpT1 on the ATPase activity of ClpD declines. CONCLUSIONS The accessory protein ClpT1 behaves as a monomer in solution. It interacts with the chloroplastic Hsp100 chaperones ClpC2 and ClpD and tightly modulates the ATPase activity of the latter. Our results provide new experimental evidence that may contribute to revise and expand the existing models that were proposed to explain the roles of this poorly understood regulatory protein.
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Affiliation(s)
- Clara V Colombo
- Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Esmeralda y Ocampo, Rosario, Argentina
| | - Eduardo A Ceccarelli
- Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Esmeralda y Ocampo, Rosario, Argentina
| | - Germán L Rosano
- Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Esmeralda y Ocampo, Rosario, Argentina
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Ramundo S, Casero D, Mühlhaus T, Hemme D, Sommer F, Crèvecoeur M, Rahire M, Schroda M, Rusch J, Goodenough U, Pellegrini M, Perez-Perez ME, Crespo JL, Schaad O, Civic N, Rochaix JD. Conditional Depletion of the Chlamydomonas Chloroplast ClpP Protease Activates Nuclear Genes Involved in Autophagy and Plastid Protein Quality Control. THE PLANT CELL 2014; 26:2201-2222. [PMID: 24879428 PMCID: PMC4079378 DOI: 10.1105/tpc.114.124842] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Revised: 04/16/2014] [Accepted: 05/09/2014] [Indexed: 05/14/2023]
Abstract
Plastid protein homeostasis is critical during chloroplast biogenesis and responses to changes in environmental conditions. Proteases and molecular chaperones involved in plastid protein quality control are encoded by the nucleus except for the catalytic subunit of ClpP, an evolutionarily conserved serine protease. Unlike its Escherichia coli ortholog, this chloroplast protease is essential for cell viability. To study its function, we used a recently developed system of repressible chloroplast gene expression in the alga Chlamydomonas reinhardtii. Using this repressible system, we have shown that a selective gradual depletion of ClpP leads to alteration of chloroplast morphology, causes formation of vesicles, and induces extensive cytoplasmic vacuolization that is reminiscent of autophagy. Analysis of the transcriptome and proteome during ClpP depletion revealed a set of proteins that are more abundant at the protein level, but not at the RNA level. These proteins may comprise some of the ClpP substrates. Moreover, the specific increase in accumulation, both at the RNA and protein level, of small heat shock proteins, chaperones, proteases, and proteins involved in thylakoid maintenance upon perturbation of plastid protein homeostasis suggests the existence of a chloroplast-to-nucleus signaling pathway involved in organelle quality control. We suggest that this represents a chloroplast unfolded protein response that is conceptually similar to that observed in the endoplasmic reticulum and in mitochondria.
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Affiliation(s)
- Silvia Ramundo
- Departments of Molecular Biology and Plant Biology, University of Geneva, 1211 Geneva, Switzerland
| | - David Casero
- Institute for Genomics and Proteomics, University of California, Los Angeles, California 90095
| | - Timo Mühlhaus
- Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm Germany
| | - Dorothea Hemme
- Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm Germany
| | - Frederik Sommer
- Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm Germany
| | - Michèle Crèvecoeur
- Departments of Molecular Biology and Plant Biology, University of Geneva, 1211 Geneva, Switzerland
| | - Michèle Rahire
- Departments of Molecular Biology and Plant Biology, University of Geneva, 1211 Geneva, Switzerland
| | - Michael Schroda
- Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm Germany
| | - Jannette Rusch
- Department of Biology, Washington University, St. Louis, Missouri 63130
| | - Ursula Goodenough
- Department of Biology, Washington University, St. Louis, Missouri 63130
| | - Matteo Pellegrini
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095
| | - Maria Esther Perez-Perez
- Instituto de Bioquimica Vegetal y Fotosintesis, Consejo Superior de Investigaciones Cientificas, Universidad de Sevilla, 41092 Sevilla, Spain
| | - José Luis Crespo
- Instituto de Bioquimica Vegetal y Fotosintesis, Consejo Superior de Investigaciones Cientificas, Universidad de Sevilla, 41092 Sevilla, Spain
| | - Olivier Schaad
- Genomics Platform, University of Geneva, 1211 Geneva, Switzerland Department of Biochemistry, University of Geneva, 1211 Geneva, Switzerland
| | - Natacha Civic
- Genomics Platform, University of Geneva, 1211 Geneva, Switzerland
| | - Jean David Rochaix
- Departments of Molecular Biology and Plant Biology, University of Geneva, 1211 Geneva, Switzerland
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40
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Sjögren LLE, Tanabe N, Lymperopoulos P, Khan NZ, Rodermel SR, Aronsson H, Clarke AK. Quantitative analysis of the chloroplast molecular chaperone ClpC/Hsp93 in Arabidopsis reveals new insights into its localization, interaction with the Clp proteolytic core, and functional importance. J Biol Chem 2014; 289:11318-11330. [PMID: 24599948 DOI: 10.1074/jbc.m113.534552] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The molecular chaperone ClpC/Hsp93 is essential for chloroplast function in vascular plants. ClpC has long been held to act both independently and as the regulatory partner for the ATP-dependent Clp protease, and yet this and many other important characteristics remain unclear. In this study, we reveal that of the two near-identical ClpC paralogs (ClpC1 and ClpC2) in Arabidopsis chloroplasts, along with the closely related ClpD, it is ClpC1 that is the most abundant throughout leaf maturation. An unexpectedly large proportion of both chloroplast ClpC proteins (30% of total ClpC content) associates to envelope membranes in addition to their stromal localization. The Clp proteolytic core is also bound to envelope membranes, the amount of which is sufficient to bind to all the similarly localized ClpC. The role of such an envelope membrane Clp protease remains unclear although it appears uninvolved in preprotein processing or Tic subunit protein turnover. Within the stroma, the amount of oligomeric ClpC protein is less than that of the Clp proteolytic core, suggesting most if not all stromal ClpC functions as part of the Clp protease; a proposal supported by the near abolition of Clp degradation activity in the clpC1 knock-out mutant. Overall, ClpC appears to function primarily within the Clp protease, as the principle stromal protease responsible for maintaining homeostasis, and also on the envelope membrane where it possibly confers a novel protein quality control mechanism for chloroplast preprotein import.
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Affiliation(s)
- Lars L E Sjögren
- From the Department of Biological and Environmental Sciences, Gothenburg University, Box 461, 405 30 Gothenburg, Sweden and
| | - Noriaki Tanabe
- From the Department of Biological and Environmental Sciences, Gothenburg University, Box 461, 405 30 Gothenburg, Sweden and
| | - Panagiotis Lymperopoulos
- From the Department of Biological and Environmental Sciences, Gothenburg University, Box 461, 405 30 Gothenburg, Sweden and
| | - Nadir Z Khan
- From the Department of Biological and Environmental Sciences, Gothenburg University, Box 461, 405 30 Gothenburg, Sweden and
| | - Steven R Rodermel
- the Department of Genetics, Development and Cell Biology, Iowa State University, Ames, Iowa 50011
| | - Henrik Aronsson
- From the Department of Biological and Environmental Sciences, Gothenburg University, Box 461, 405 30 Gothenburg, Sweden and
| | - Adrian K Clarke
- From the Department of Biological and Environmental Sciences, Gothenburg University, Box 461, 405 30 Gothenburg, Sweden and.
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Wu W, Zhu Y, Ma Z, Sun Y, Quan Q, Li P, Hu P, Shi T, Lo C, Chu IK, Huang J. Proteomic evidence for genetic epistasis: ClpR4 mutations switch leaf variegation to virescence in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 76:943-956. [PMID: 24124904 DOI: 10.1111/tpj.12344] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 09/26/2013] [Accepted: 10/01/2013] [Indexed: 05/28/2023]
Abstract
Chloroplast development in plants is regulated by a series of coordinated biological processes. In this work, a genetic suppressor screen for the leaf variegation phenotype of the thylakoid formation 1 (thf1) mutant combined with a proteomic assay was employed to elucidate this complicated network. We identified a mutation in ClpR4, named clpR4-3, which leads to leaf virescence and also rescues the var2 variegation. Proteomic analysis showed that the chloroplast proteome of clpR4-3 thf1 is dominantly controlled by clpR4-3, providing molecular mechanisms that cause genetic epistasis of clpR4-3 to thf1. Classification of the proteins significantly mis-regulated in the mutants revealed that those functioning in the expression of plastid genes are oppositely regulated while proteins functioning in antioxidative stress, protein folding, and starch metabolism are changed in the same direction between thf1 and clpR4-3. The levels of FtsHs including FtsH2/VAR2, FtsH8, and FtsH5/VAR1 are greatly reduced in thf1 compared with those in the wild type, but are higher in clpR4-3 thf1 than in thf1. Quantitative PCR analysis revealed that FtsH expression in clpR4-3 thf1 is regulated post-transcriptionally. In addition, a number of ribosomal proteins are less expressed in the clpR4-3 proteome, which is in line with the reduced levels of rRNAs in clpR4-3. Furthermore, knocking out PRPL11, one of the most downregulated proteins in the clpR4-3 thf1 proteome, rescues the leaf variegation phenotype of the thf1 and var2 mutants. These results provide insights into molecular mechanisms by which the virescent clpR4-3 mutation suppresses leaf variegation of thf1 and var2.
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Affiliation(s)
- Wenjuan Wu
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
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42
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Li W, Wu C, Hu G, Xing L, Qian W, Si H, Sun Z, Wang X, Fu Y, Liu W. Characterization and fine mapping of a novel rice narrow leaf mutant nal9. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2013; 55:1016-25. [PMID: 23945310 DOI: 10.1111/jipb.12098] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 06/22/2013] [Indexed: 05/09/2023]
Abstract
A narrow leaf mutant was isolated from transgenic rice (Oryza sativa L.) lines carrying a T-DNA insertion. The mutant is characterized by narrow leaves during its whole growth period, and was named nal9 (narrow leaf 9). The mutant also has other phenotypes, such as light green leaves at the seedling stage, reduced plant height, a small panicle and increased tillering. Genetic analysis revealed that the mutation is controlled by a single recessive gene. A hygromycin resistance assay showed that the mutation was not caused by T-DNA insertion, so a map-based cloning strategy was employed to isolate the nal9 gene. The mutant individuals from the F₂ generations of a cross between the nal9 mutant and Longtepu were used for mapping. With 24 F₂ mutants, the nal9 gene was preliminarily mapped near the marker RM156 on the chromosome 3. New INDEL markers were then designed based on the sequence differences between japonica and indica at the region near RM156. The nal9 gene was finally located in a 69.3 kb region between the markers V239B and V239G within BAC OJ1212_C05 by chromosome walking. Sequence and expression analysis showed that an ATP-dependent Clp protease proteolytic subunit gene (ClpP) was most likely to be the nal9 gene. Furthermore, the nal9 mutation was rescued by transformation of the ClpP cDNA driven by the 35S promoter. Accordingly, the ClpP gene was identified as the NAL9 gene. Our results provide a basis for functional studies of NAL9 in future work.
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Affiliation(s)
- Wei Li
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China; College of Life Sciences, Shanxi Agricultural University, Taigu, 030801, China
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43
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Dong H, Fei GL, Wu CY, Wu FQ, Sun YY, Chen MJ, Ren YL, Zhou KN, Cheng ZJ, Wang JL, Jiang L, Zhang X, Guo XP, Lei CL, Su N, Wang H, Wan JM. A rice virescent-yellow leaf mutant reveals new insights into the role and assembly of plastid caseinolytic protease in higher plants. PLANT PHYSIOLOGY 2013; 162:1867-80. [PMID: 23803583 PMCID: PMC3729767 DOI: 10.1104/pp.113.217604] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2013] [Accepted: 06/24/2013] [Indexed: 05/20/2023]
Abstract
The plastidic caseinolytic protease (Clp) of higher plants is an evolutionarily conserved protein degradation apparatus composed of a proteolytic core complex (the P and R rings) and a set of accessory proteins (ClpT, ClpC, and ClpS). The role and molecular composition of Clps in higher plants has just begun to be unraveled, mostly from studies with the model dicotyledonous plant Arabidopsis (Arabidopsis thaliana). In this work, we isolated a virescent yellow leaf (vyl) mutant in rice (Oryza sativa), which produces chlorotic leaves throughout the entire growth period. The young chlorotic leaves turn green in later developmental stages, accompanied by alterations in chlorophyll accumulation, chloroplast ultrastructure, and the expression of chloroplast development- and photosynthesis-related genes. Positional cloning revealed that the VYL gene encodes a protein homologous to the Arabidopsis ClpP6 subunit and that it is targeted to the chloroplast. VYL expression is constitutive in most tissues examined but most abundant in leaf sections containing chloroplasts in early stages of development. The mutation in vyl causes premature termination of the predicted gene product and loss of the conserved catalytic triad (serine-histidine-aspartate) and the polypeptide-binding site of VYL. Using a tandem affinity purification approach and mass spectrometry analysis, we identified OsClpP4 as a VYL-associated protein in vivo. In addition, yeast two-hybrid assays demonstrated that VYL directly interacts with OsClpP3 and OsClpP4. Furthermore, we found that OsClpP3 directly interacts with OsClpT, that OsClpP4 directly interacts with OsClpP5 and OsClpT, and that both OsClpP4 and OsClpT can homodimerize. Together, our data provide new insights into the function, assembly, and regulation of Clps in higher plants.
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44
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Nishimura K, Asakura Y, Friso G, Kim J, Oh SH, Rutschow H, Ponnala L, van Wijk KJ. ClpS1 is a conserved substrate selector for the chloroplast Clp protease system in Arabidopsis. THE PLANT CELL 2013; 25:2276-301. [PMID: 23898032 PMCID: PMC3723626 DOI: 10.1105/tpc.113.112557] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 05/24/2013] [Accepted: 06/06/2013] [Indexed: 05/18/2023]
Abstract
Whereas the plastid caseinolytic peptidase (Clp) P protease system is essential for plant development, substrates and substrate selection mechanisms are unknown. Bacterial ClpS is involved in N-degron substrate selection and delivery to the ClpAP protease. Through phylogenetic analysis, we show that all angiosperms contain ClpS1 and some species also contain ClpS1-like protein(s). In silico analysis suggests that ClpS1 is the functional homolog of bacterial ClpS. We show that Arabidopsis thaliana ClpS1 interacts with plastid ClpC1,2 chaperones. The Arabidopsis ClpS1 null mutant (clps1) lacks a visible phenotype, and no genetic interactions with ClpC/D chaperone or ClpPR core mutants were observed. However, clps1, but not clpc1-1, has increased sensitivity to the translational elongation inhibitor chloramphenicol suggesting a link between translational capacity and ClpS1. Moreover, ClpS1 was upregulated in clpc1-1, and quantitative proteomics of clps1, clpc1, and clps1 clpc1 showed specific molecular phenotypes attributed to loss of ClpC1 or ClpS1. In particular, clps1 showed alteration of the tetrapyrrole pathway. Affinity purification identified eight candidate ClpS1 substrates, including plastid DNA repair proteins and Glu tRNA reductase, which is a control point for tetrapyrrole synthesis. ClpS1 interaction with five substrates strictly depended on two conserved ClpS1 residues involved in N-degron recognition. ClpS1 function, substrates, and substrate recognition mechanisms are discussed.
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Affiliation(s)
- Kenji Nishimura
- Department of Plant Biology, Cornell University, Ithaca, New York 14853
| | - Yukari Asakura
- Department of Plant Biology, Cornell University, Ithaca, New York 14853
| | - Giulia Friso
- Department of Plant Biology, Cornell University, Ithaca, New York 14853
| | - Jitae Kim
- Department of Plant Biology, Cornell University, Ithaca, New York 14853
| | - Soo-hyun Oh
- Department of Plant Biology, Cornell University, Ithaca, New York 14853
| | - Heidi Rutschow
- Department of Plant Biology, Cornell University, Ithaca, New York 14853
| | - Lalit Ponnala
- Computational Biology Service Unit, Cornell University, Ithaca, New York, 14853
| | - Klaas J. van Wijk
- Computational Biology Service Unit, Cornell University, Ithaca, New York, 14853
- Address correspondence to
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45
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Kim J, Olinares PD, Oh SH, Ghisaura S, Poliakov A, Ponnala L, van Wijk KJ. Modified Clp protease complex in the ClpP3 null mutant and consequences for chloroplast development and function in Arabidopsis. PLANT PHYSIOLOGY 2013; 162:157-79. [PMID: 23548781 PMCID: PMC3641200 DOI: 10.1104/pp.113.215699] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 03/27/2013] [Indexed: 05/18/2023]
Abstract
The plastid ClpPRT protease consists of two heptameric rings of ClpP1/ClpR1/ClpR2/ClpR3/ClpR4 (the R-ring) and ClpP3/ClpP4/ClpP5/ClpP6 (the P-ring) and peripherally associated ClpT1/ClpT2 subunits. Here, we address the contributions of ClpP3 and ClpP4 to ClpPRT core organization and function in Arabidopsis (Arabidopsis thaliana). ClpP4 is strictly required for embryogenesis, similar to ClpP5. In contrast, loss of ClpP3 (clpp3-1) leads to arrest at the hypocotyl stage; this developmental arrest can be removed by supplementation with sucrose or glucose. Heterotrophically grown clpp3-1 can be transferred to soil and generate viable seed, which is surprising, since we previously showed that CLPR2 and CLPR4 null alleles are always sterile and die on soil. Based on native gels and mass spectrometry-based quantification, we show that despite the loss of ClpP3, modified ClpPR core(s) could be formed, albeit at strongly reduced levels. A large portion of ClpPR subunits accumulated in heptameric rings, with overaccumulation of ClpP1/ClpP5/ClpP6 and ClpR3. Remarkably, the association of ClpT1 to the modified Clp core was unchanged. Large-scale quantitative proteomics assays of clpp3-1 showed a 50% loss of photosynthetic capacity and the up-regulation of plastoglobules and all chloroplast stromal chaperone systems. Specific chloroplast proteases were significantly up-regulated, whereas the major thylakoid protease (FtsH1/FtsH2/FtsH5/FtsH8) was clearly unchanged, indicating a controlled protease network response. clpp3-1 showed a systematic decrease of chloroplast-encoded proteins that are part of the photosynthetic apparatus but not of chloroplast-encoded proteins with other functions. Candidate substrates and an explanation for the differential phenotypes between the CLPP3, CLPP4, and CLPP5 null mutants are discussed.
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46
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Derrien B, Majeran W, Effantin G, Ebenezer J, Friso G, van Wijk KJ, Steven AC, Maurizi MR, Vallon O. The purification of the Chlamydomonas reinhardtii chloroplast ClpP complex: additional subunits and structural features. PLANT MOLECULAR BIOLOGY 2012; 80:189-202. [PMID: 22772861 PMCID: PMC3500782 DOI: 10.1007/s11103-012-9939-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 06/28/2012] [Indexed: 05/23/2023]
Abstract
The ClpP peptidase is a major constituent of the proteolytic machinery of bacteria and organelles. The chloroplast ClpP complex is unusual, in that it associates a large number of subunits, one of which (ClpP1) is encoded in the chloroplast, the others in the nucleus. The complexity of these large hetero-oligomeric complexes has been a major difficulty in their overproduction and biochemical characterization. In this paper, we describe the purification of native chloroplast ClpP complex from the green alga Chlamydomonas reinhardtii, using a strain that carries the Strep-tag II at the C-terminus of the ClpP1 subunit. Similar to land plants, the algal complex comprises active and inactive subunits (3 ClpP and 5 ClpR, respectively). Evidence is presented that a sub-complex can be produced by dissociation, comprising ClpP1 and ClpR1, 2, 3 and 4, similar to the ClpR-ring described in land plants. Our Chlamydomonas ClpP preparation also contains two ClpT subunits, ClpT3 and ClpT4, which like the land plant ClpT1 and ClpT2 show 2 Clp-N domains. ClpTs are believed to function in substrate binding and/or assembly of the two heptameric rings. Phylogenetic analysis indicates that ClpT subunits have appeared independently in Chlorophycean algae, in land plants and in dispersed cyanobacterial genomes. Negative staining electron microscopy shows that the Chlamydomonas complex retains the barrel-like shape of homo-oligomeric ClpPs, with 4 additional peripheral masses that we speculate represent either the additional IS1 domain of ClpP1 (a feature unique to algae) or ClpTs or extensions of ClpR subunits.
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Affiliation(s)
- Benoît Derrien
- UMR7141 CNRS/UPMC, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Wojciech Majeran
- Department of Plant Biology, Cornell University, Ithaca, New York 14853
- Université Paris Diderot, Sorbonne Paris Cité, Institut des Sciences du Végétal, UPR 2355 CNRS, 1 Avenue de la Terrasse, 91198 Gif/Yvette cedex, France
| | - Grégory Effantin
- Laboratory of Structural Biology Research, NIAMS, NIH, Bethesda, USA
| | | | - Giulia Friso
- Department of Plant Biology, Cornell University, Ithaca, New York 14853
| | - Klaas J. van Wijk
- Department of Plant Biology, Cornell University, Ithaca, New York 14853
| | | | | | - Olivier Vallon
- UMR7141 CNRS/UPMC, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005 Paris, France
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47
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Interaction specificity between the chaperone and proteolytic components of the cyanobacterial Clp protease. Biochem J 2012; 446:311-20. [DOI: 10.1042/bj20120649] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The Clp protease is conserved among eubacteria and most eukaryotes, and uses ATP to drive protein substrate unfolding and translocation into a chamber of sequestered proteolytic active sites. In plant chloroplasts and cyanobacteria, the essential constitutive Clp protease consists of the Hsp100/ClpC chaperone partnering a proteolytic core of catalytic ClpP and noncatalytic ClpR subunits. In the present study, we have examined putative determinants conferring the highly specific association between ClpC and the ClpP3/R core from the model cyanobacterium Synechococcus elongatus. Two conserved sequences in the N-terminus of ClpR (tyrosine and proline motifs) and one in the N-terminus of ClpP3 (MPIG motif) were identified as being crucial for the ClpC–ClpP3/R association. These N-terminal domains also influence the stability of the ClpP3/R core complex itself. A unique C-terminal sequence was also found in plant and cyanobacterial ClpC orthologues just downstream of the P-loop region previously shown in Escherichia coli to be important for Hsp100 association to ClpP. This R motif in Synechococcus ClpC confers specificity for the ClpP3/R core and prevents association with E. coli ClpP; its removal from ClpC reverses this core specificity.
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48
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Kato Y, Sun X, Zhang L, Sakamoto W. Cooperative D1 degradation in the photosystem II repair mediated by chloroplastic proteases in Arabidopsis. PLANT PHYSIOLOGY 2012; 159:1428-39. [PMID: 22698923 PMCID: PMC3425188 DOI: 10.1104/pp.112.199042] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Light energy constantly damages photosynthetic apparatuses, ultimately causing impaired growth. Particularly, the sessile nature of higher plants has allowed chloroplasts to develop unique mechanisms to alleviate the irreversible inactivation of photosynthesis. Photosystem II (PSII) is known as a primary target of photodamage. Photosynthetic organisms have evolved the so-called PSII repair cycle, in which a reaction center protein, D1, is degraded rapidly in a specific manner. Two proteases that perform processive or endopeptidic degradation, FtsH and Deg, respectively, participate in this cycle. To examine the cooperative D1 degradation by these proteases, we engaged Arabidopsis (Arabidopsis thaliana) mutants lacking FtsH2 (yellow variegated2 [var2]) and Deg5/Deg8 (deg5 deg8) in detecting D1 cleaved fragments. We detected several D1 fragments only under the var2 background, using amino-terminal or carboxyl-terminal specific antibodies of D1. The appearance of these D1 fragments was inhibited by a serine protease inhibitor and by deg5 deg8 mutations. Given the localization of Deg5/Deg8 on the luminal side of thylakoid membranes, we inferred that Deg5/Deg8 cleaves D1 at its luminal loop connecting the transmembrane helices C and D and that the cleaved products of D1 are the substrate for FtsH. These D1 fragments detected in var2 were associated with the PSII monomer, dimer, and partial disassembly complex but not with PSII supercomplexes. It is particularly interesting that another processive protease, Clp, was up-regulated and appeared to be recruited from stroma to the thylakoid membrane in var2, suggesting compensation for FtsH deficiency. Together, our data demonstrate in vivo cooperative degradation of D1, in which Deg cleavage assists FtsH processive degradation under photoinhibitory conditions.
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Tsiatsiani L, Gevaert K, Van Breusegem F. Natural substrates of plant proteases: how can protease degradomics extend our knowledge? PHYSIOLOGIA PLANTARUM 2012; 145:28-40. [PMID: 22008056 DOI: 10.1111/j.1399-3054.2011.01534.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Despite the key role of proteolysis in various intensively studied biological processes, such as plant immunity, seed development and abiotic stress responses, our knowledge on the identity of natural protease substrates in plants remains scarce. In the genome of the model plant Arabidopsis thaliana, for instance, approximately 700 genes code for proteases. However, only a few natural substrates have been identified, mainly because of the previous lack of sensitive proteomics technologies enabling the identification of low abundant proteins, together with a delay in the implementation of these technologies in the field of plant research. Here, we review the current knowledge on the identity of natural plant protease substrates and describe recently established degradomics technologies that should allow proteome-wide studies of plant proteases in the near future.
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Affiliation(s)
- Liana Tsiatsiani
- Department of Plant Systems Biology, VIB, Technologiepark 927, B-9052 Ghent, Belgium
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50
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Clarke AK. The chloroplast ATP-dependent Clp protease in vascular plants - new dimensions and future challenges. PHYSIOLOGIA PLANTARUM 2012; 145:235-44. [PMID: 22085372 DOI: 10.1111/j.1399-3054.2011.01541.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The ATP-dependent Clp protease is by far the most intricate protease in chloroplasts of vascular plants. Structurally, it is particularly complex with a proteolytic core complex containing 11 distinct subunits along with three potential chaperone partners. The Clp protease is also essential for chloroplast development and overall plant viability. Over the past decade, many of the important characteristics of this crucial protease have been revealed in the model plant species Arabidopsis thaliana. Despite this, challenges still remain in fully resolving certain key features, in particular, how the assembly of this multisubunit protease is regulated, the full range of native protein substrates and how they are targeted for degradation and how this complicated enzyme might have developed from simpler bacterial forms. This article focuses upon the recent advances in revealing the details underlying these important features. It also take the opportunity to speculate upon many of these findings in the hope of stimulating further investigation.
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Affiliation(s)
- Adrian K Clarke
- Department of Plant and Environmental Sciences, Gothenburg University, 40530 Gothenburg, Sweden.
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