1
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van Wijk KJ, Leppert T, Sun Z, Guzchenko I, Debley E, Sauermann G, Routray P, Mendoza L, Sun Q, Deutsch EW. The Zea mays PeptideAtlas: A New Maize Community Resource. J Proteome Res 2024. [PMID: 39101213 DOI: 10.1021/acs.jproteome.4c00320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/06/2024]
Abstract
This study presents the Maize PeptideAtlas resource (www.peptideatlas.org/builds/maize) to help solve questions about the maize proteome. Publicly available raw tandem mass spectrometry (MS/MS) data for maize collected from ProteomeXchange were reanalyzed through a uniform processing and metadata annotation pipeline. These data are from a wide range of genetic backgrounds and many sample types and experimental conditions. The protein search space included different maize genome annotations for the B73 inbred line from MaizeGDB, UniProtKB, NCBI RefSeq, and for the W22 inbred line. 445 million MS/MS spectra were searched, of which 120 million were matched to 0.37 million distinct peptides. Peptides were matched to 66.2% of proteins in the most recent B73 nuclear genome annotation. Furthermore, most conserved plastid- and mitochondrial-encoded proteins (NCBI RefSeq annotations) were identified. Peptides and proteins identified in the other B73 genome annotations will improve maize genome annotation. We also illustrate the high-confidence detection of unique W22 proteins. N-terminal acetylation, phosphorylation, ubiquitination, and three lysine acylations (K-acetyl, K-malonyl, and K-hydroxyisobutyryl) were identified and can be inspected through a PTM viewer in PeptideAtlas. All matched MS/MS-derived peptide data are linked to spectral, technical, and biological metadata. This new PeptideAtlas is integrated in MaizeGDB with a peptide track in JBrowse.
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Affiliation(s)
- Klaas J van Wijk
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, New York 14853, United States
| | - Tami Leppert
- Institute for Systems Biology (ISB), Seattle, Washington 98109, United States
| | - Zhi Sun
- Institute for Systems Biology (ISB), Seattle, Washington 98109, United States
| | - Isabell Guzchenko
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, New York 14853, United States
| | - Erica Debley
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, New York 14853, United States
| | - Georgia Sauermann
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, New York 14853, United States
| | - Pratyush Routray
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, New York 14853, United States
| | - Luis Mendoza
- Institute for Systems Biology (ISB), Seattle, Washington 98109, United States
| | - Qi Sun
- Computational Biology Service Unit, Cornell University, Ithaca, New York 14853, United States
| | - Eric W Deutsch
- Institute for Systems Biology (ISB), Seattle, Washington 98109, United States
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2
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Legen J, Lenzen B, Kachariya N, Feltgen S, Gao Y, Mergenthal S, Weber W, Klotzsch E, Zoschke R, Sattler M, Schmitz-Linneweber C. A prion-like domain is required for phase separation and chloroplast RNA processing during cold acclimation in Arabidopsis. THE PLANT CELL 2024; 36:2851-2872. [PMID: 38723165 PMCID: PMC11289645 DOI: 10.1093/plcell/koae145] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 04/06/2024] [Indexed: 08/02/2024]
Abstract
Arabidopsis (Arabidopsis thaliana) plants can produce photosynthetic tissue with active chloroplasts at temperatures as low as 4°C, and this process depends on the presence of the nuclear-encoded, chloroplast-localized RNA-binding protein CP29A. In this study, we demonstrate that CP29A undergoes phase separation in vitro and in vivo in a temperature-dependent manner, which is mediated by a prion-like domain (PLD) located between the two RNA recognition motif domains of CP29A. The resulting droplets display liquid-like properties and are found near chloroplast nucleoids. The PLD is required to support chloroplast RNA splicing and translation in cold-treated tissue. Together, our findings suggest that plant chloroplast gene expression is compartmentalized by inducible condensation of CP29A at low temperatures, a mechanism that could play a crucial role in plant cold resistance.
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Affiliation(s)
- Julia Legen
- Molecular Genetics, Humboldt Universität zu Berlin, Philippstrasse 13, Berlin 10115, Germany
| | - Benjamin Lenzen
- Molecular Genetics, Humboldt Universität zu Berlin, Philippstrasse 13, Berlin 10115, Germany
| | - Nitin Kachariya
- Helmholtz Munich, Institute of Structural Biology, Ingolstädter Landstrasse 1, Munich 85764, Germany
- Department of Bioscience, Bavarian NMR Center, TUM School of Natural Sciences, Technical University of Munich, Lichtenbergstrasse 4, Garching 85747, Germany
| | - Stephanie Feltgen
- Molecular Genetics, Humboldt Universität zu Berlin, Philippstrasse 13, Berlin 10115, Germany
| | - Yang Gao
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, Potsdam-Golm 14476, Germany
| | - Simon Mergenthal
- Institute for Biology, Experimental Biophysics/Mechanobiology, Humboldt-Universität zu Berlin, Invalidenstrasse 42, Berlin 10115, Germany
| | - Willi Weber
- Institute for Biology, Experimental Biophysics/Mechanobiology, Humboldt-Universität zu Berlin, Invalidenstrasse 42, Berlin 10115, Germany
| | - Enrico Klotzsch
- Institute for Biology, Experimental Biophysics/Mechanobiology, Humboldt-Universität zu Berlin, Invalidenstrasse 42, Berlin 10115, Germany
| | - Reimo Zoschke
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, Potsdam-Golm 14476, Germany
| | - Michael Sattler
- Helmholtz Munich, Institute of Structural Biology, Ingolstädter Landstrasse 1, Munich 85764, Germany
- Department of Bioscience, Bavarian NMR Center, TUM School of Natural Sciences, Technical University of Munich, Lichtenbergstrasse 4, Garching 85747, Germany
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3
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Sun X, Singla-Rastogi M, Wang J, Zhao C, Wang X, Li P. The uS10c-BPG2 module mediates ribosomal RNA processing in chloroplast nucleoids. Nucleic Acids Res 2024; 52:7893-7909. [PMID: 38686791 PMCID: PMC11260468 DOI: 10.1093/nar/gkae339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 04/09/2024] [Accepted: 04/17/2024] [Indexed: 05/02/2024] Open
Abstract
In plant chloroplasts, certain ribosomal proteins (RPs) and ribosome biogenesis factors (RBFs) are present in nucleoids, implying an association between nucleoids and ribosome biogenesis. In Arabidopsis, the YqeH-type GTPase Brassinazole-Insensitive Pale Green2 (BPG2) is a chloroplast nucleoid-associated RBF. Here, we investigated the relationship between nucleoids and BPG2-involved ribosome biogenesis steps by exploring how BPG2 targets ribosomes. Our findings demonstrate that BPG2 interacts with an essential plastid RP, uS10c, in chloroplast nucleoids in a ribosomal RNA (rRNA)-independent manner. We also discovered that uS10c is a haploinsufficient gene, as the heterozygous deletion of this gene leads to variegated shoots and chlorophyll aggregation. uS10c is integrated into 30S ribosomal particles when rRNA is relatively exposed and also exists in polysome fractions. In contrast, BPG2 exclusively associates with 30S ribosomal particles. Notably, the interaction between BPG2 and 30S particles is influenced by the absence of uS10c, resulting in BPG2 diffusing in chloroplasts instead of targeting nucleoids. Further, our results reveal that the loss of BPG2 function and the heterozygous deletion of uS10c impair the processing of 16S and 23S-4.5S rRNAs, reduce plastid protein accumulation, and trigger the plastid signaling response. Together, these findings indicate that the uS10c-BPG2 module mediates ribosome biogenesis in chloroplast nucleoids.
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Affiliation(s)
- Xueping Sun
- Institute of Crop Germplasm Resources (Biotechnology Research Center), Shandong Academy of Agricultural Sciences; Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan, Shandong 250100, PR China
- College of Life Sciences, Shandong Normal University, Jinan, Shandong 250014, PR China
| | | | - Jingwen Wang
- Institute of Crop Germplasm Resources (Biotechnology Research Center), Shandong Academy of Agricultural Sciences; Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan, Shandong 250100, PR China
- College of Life Sciences, Shandong Normal University, Jinan, Shandong 250014, PR China
| | - Chuanzhi Zhao
- Institute of Crop Germplasm Resources (Biotechnology Research Center), Shandong Academy of Agricultural Sciences; Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan, Shandong 250100, PR China
| | - Xingjun Wang
- Institute of Crop Germplasm Resources (Biotechnology Research Center), Shandong Academy of Agricultural Sciences; Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan, Shandong 250100, PR China
| | - Pengcheng Li
- Institute of Crop Germplasm Resources (Biotechnology Research Center), Shandong Academy of Agricultural Sciences; Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan, Shandong 250100, PR China
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
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Sloan DB, Broz AK, Kuster SA, Muthye V, Peñafiel-Ayala A, Marron JR, Lavrov DV, Brieba LG. Expansion of the MutS Gene Family in Plants. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.17.603841. [PMID: 39071318 PMCID: PMC11275761 DOI: 10.1101/2024.07.17.603841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
The MutS gene family is distributed across the tree of life and is involved in recombination, DNA repair, and protein translation. Multiple evolutionary processes have expanded the set of MutS genes in plants relative to other eukaryotes. Here, we investigate the origins and functions of these plant-specific genes. Land plants, green algae, red algae, and glaucophytes share cyanobacterial-like MutS1 and MutS2 genes that presumably were gained via plastid endosymbiotic gene transfer. MutS1 was subsequently lost in some taxa, including seed plants, whereas MutS2 was duplicated in Viridiplantae (i.e., land plants and green algae) with widespread retention of both resulting paralogs. Viridiplantae also have two anciently duplicated copies of the eukaryotic MSH6 gene (i.e., MSH6 and MSH7) and acquired MSH1 via horizontal gene transfer - potentially from a nucleocytovirus. Despite sharing the same name, "plant MSH1" is not directly related to the gene known as MSH1 in some fungi and animals, which may be an ancestral eukaryotic gene acquired via mitochondrial endosymbiosis and subsequently lost in most eukaryotic lineages. There has been substantial progress in understanding the functions of MSH1 and MSH6/MSH7 in plants, but the roles of the cyanobacterial-like MutS1 and MutS2 genes remain uncharacterized. Known functions of bacterial homologs and predicted protein structures, including fusions to diverse nuclease domains, provide hypotheses about potential molecular mechanisms. Because most plant-specific MutS proteins are targeted to the mitochondria and/or plastids, the expansion of this family appears to have played a large role in shaping plant organelle genetics.
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Affiliation(s)
- Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Amanda K Broz
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Shady A Kuster
- Department of Biology, Colorado State University, Fort Collins, CO, USA
- Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO, USA
| | - Viraj Muthye
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Alejandro Peñafiel-Ayala
- Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Gto, México
| | - Jennifer R Marron
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Dennis V Lavrov
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, USA
| | - Luis G Brieba
- Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Gto, México
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5
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Palomar VM, Cho Y, Fujii S, Rothi MH, Jaksich S, Min JH, Schlachter AN, Wang J, Liu Z, Wierzbicki AT. Membrane association of active genes organizes the chloroplast nucleoid structure. Proc Natl Acad Sci U S A 2024; 121:e2309244121. [PMID: 38968115 PMCID: PMC11252823 DOI: 10.1073/pnas.2309244121] [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: 06/01/2023] [Accepted: 05/24/2024] [Indexed: 07/07/2024] Open
Abstract
DNA is organized into chromatin-like structures that support the maintenance and regulation of genomes. A unique and poorly understood form of DNA organization exists in chloroplasts, which are organelles of endosymbiotic origin responsible for photosynthesis. Chloroplast genomes, together with associated proteins, form membrane-less structures known as nucleoids. The internal arrangement of the nucleoid, molecular mechanisms of DNA organization, and connections between nucleoid structure and gene expression remain mostly unknown. We show that Arabidopsis thaliana chloroplast nucleoids have a unique sequence-specific organization driven by DNA binding to the thylakoid membranes. DNA associated with the membranes has high protein occupancy, has reduced DNA accessibility, and is highly transcribed. In contrast, genes with low levels of transcription are further away from the membranes, have lower protein occupancy, and have higher DNA accessibility. Membrane association of active genes relies on the pattern of transcription and proper chloroplast development. We propose a speculative model that transcription organizes the chloroplast nucleoid into a transcriptionally active membrane-associated core and a less active periphery.
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Affiliation(s)
- V. Miguel Palomar
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI48109
- Departamento de Bioquímica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México04510, México
| | - Yoonjin Cho
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI48109
| | - Sho Fujii
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI48109
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto606-8502, Japan
- Department of Biology, Faculty of Agriculture and Life Science, Hirosaki University, Aomori036-8561, Japan
| | - M. Hafiz Rothi
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI48109
| | - Sarah Jaksich
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI48109
| | - Ji-Hee Min
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI48109
| | - Adriana N. Schlachter
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI48109
| | - Joyful Wang
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI48109
| | - Zhengde Liu
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI48109
| | - Andrzej T. Wierzbicki
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI48109
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6
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Liu Y, Zhan J, Li J, Lian M, Li J, Xia C, Zhou F, Xie W. Characterization of the DNA accessibility of chloroplast genomes in grasses. Commun Biol 2024; 7:760. [PMID: 38909165 PMCID: PMC11193712 DOI: 10.1038/s42003-024-06374-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 05/23/2024] [Indexed: 06/24/2024] Open
Abstract
Although the chloroplast genome (cpDNA) of higher plants is known to exist as a large protein-DNA complex called 'plastid nucleoid', researches on its DNA state and regulatory elements are limited. In this study, we performed the assay for transposase-accessible chromatin sequencing (ATAC-seq) on five common tissues across five grasses, and found that the accessibility of different regions in cpDNA varied widely, with the transcribed regions being highly accessible and accessibility patterns around gene start and end sites varying depending on the level of gene expression. Further analysis identified a total of 3970 putative protein binding footprints on cpDNAs of five grasses. These footprints were enriched in intergenic regions and co-localized with known functional elements. Footprints and their flanking accessibility varied dynamically among tissues. Cross-species analysis showed that footprints in coding regions tended to overlap non-degenerate sites and contain a high proportion of highly conserved sites, indicating that they are subject to evolutionary constraints. Taken together, our results suggest that the accessibility of cpDNA has biological implications and provide new insights into the transcriptional regulation of chloroplasts.
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Affiliation(s)
- Yinmeng Liu
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430000, China
- Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430000, China
| | - Jinling Zhan
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430000, China
- Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430000, China
| | - Junjie Li
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430000, China
- Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430000, China
| | - Mengjie Lian
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430000, China
- Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430000, China
| | - Jiacheng Li
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430000, China
- Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430000, China
| | - Chunjiao Xia
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430000, China
| | - Fei Zhou
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430000, China
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430000, China
| | - Weibo Xie
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430000, China.
- Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430000, China.
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7
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Huo Y, Cheng M, Tang M, Zhang M, Yang X, Zheng Y, Zhao T, He P, Yu J. GhCTSF1, a short PPR protein with a conserved role in chloroplast development and photosynthesis, participates in intron splicing of rpoC1 and ycf3-2 transcripts in cotton. PLANT COMMUNICATIONS 2024; 5:100858. [PMID: 38444162 PMCID: PMC11211521 DOI: 10.1016/j.xplc.2024.100858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 02/29/2024] [Accepted: 03/04/2024] [Indexed: 03/07/2024]
Abstract
Cotton is one of the most important textile fibers worldwide. As crucial agronomic traits, leaves play an essential role in the growth, disease resistance, fiber quality, and yield of cotton plants. Pentatricopeptide repeat (PPR) proteins are a large family of nuclear-encoded proteins involved in organellar or nuclear RNA metabolism. Using a virus-induced gene silencing assay, we found that cotton plants displayed variegated yellow leaf phenotypes with decreased chlorophyll content when expression of the PPR gene GhCTSF1 was silenced. GhCTSF1 encodes a chloroplast-localized protein that contains only two PPR motifs. Disruption of GhCTSF1 substantially reduces the splicing efficiency of rpoC1 intron 1 and ycf3 intron 2. Loss of function of the GhCTSF1 ortholog EMB1417 causes splicing defects in rpoC1 and ycf3-2, leading to impaired chloroplast structure and decreased photosynthetic rates in Arabidopsis. We also found that GhCTSF1 interacts with two splicing factors, GhCRS2 and GhWTF1. Defects in GhCRS2 and GhWTF1 severely affect intron splicing of rpoC1 and ycf3-2 in cotton, leading to defects in chloroplast development and a reduction in photosynthesis. Our results suggest that GhCTSF1 is specifically required for splicing rpoC1 and ycf3-2 in cooperation with GhCRS2 and GhWTF1.
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Affiliation(s)
- Yuzhu Huo
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Mengxue Cheng
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Meiju Tang
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Meng Zhang
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Xiaofan Yang
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Yating Zheng
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Tong Zhao
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Peng He
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China.
| | - Jianing Yu
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China.
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8
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Schmid LM, Manavski N, Chi W, Meurer J. Chloroplast Ribosome Biogenesis Factors. PLANT & CELL PHYSIOLOGY 2024; 65:516-536. [PMID: 37498958 DOI: 10.1093/pcp/pcad082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 07/13/2023] [Accepted: 07/25/2023] [Indexed: 07/29/2023]
Abstract
The formation of chloroplasts can be traced back to an ancient event in which a eukaryotic host cell containing mitochondria ingested a cyanobacterium. Since then, chloroplasts have retained many characteristics of their bacterial ancestor, including their transcription and translation machinery. In this review, recent research on the maturation of rRNA and ribosome assembly in chloroplasts is explored, along with their crucial role in plant survival and their implications for plant acclimation to changing environments. A comparison is made between the ribosome composition and auxiliary factors of ancient and modern chloroplasts, providing insights into the evolution of ribosome assembly factors. Although the chloroplast contains ancient proteins with conserved functions in ribosome assembly, newly evolved factors have also emerged to help plants acclimate to changes in their environment and internal signals. Overall, this review offers a comprehensive analysis of the molecular mechanisms underlying chloroplast ribosome assembly and highlights the importance of this process in plant survival, acclimation and adaptation.
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Affiliation(s)
- Lisa-Marie Schmid
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-University Munich, Großhaderner Street 2-4, Planegg-Martinsried 82152, Germany
| | - Nikolay Manavski
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-University Munich, Großhaderner Street 2-4, Planegg-Martinsried 82152, Germany
| | - Wei Chi
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Jörg Meurer
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-University Munich, Großhaderner Street 2-4, Planegg-Martinsried 82152, Germany
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9
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Nishimura Y. Plastid Nucleoids: Insights into Their Shape and Dynamics. PLANT & CELL PHYSIOLOGY 2024; 65:551-559. [PMID: 37542434 DOI: 10.1093/pcp/pcad090] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 07/26/2023] [Accepted: 08/04/2023] [Indexed: 08/07/2023]
Abstract
Chloroplasts/plastids are unique organelles found in plant cells and some algae and are responsible for performing essential functions such as photosynthesis. The plastid genome, consisting of circular and linear DNA molecules, is packaged and organized into specialized structures called nucleoids. The composition and dynamics of these nucleoids have been the subject of intense research, as they are critical for proper plastid functions and development. In this mini-review, recent advances in understanding the organization and regulation of plastid nucleoids are overviewed, with a focus on the various proteins and factors that regulate the shape and dynamics of nucleoids, including DNA-binding proteins and membrane anchorage proteins. The dynamic nature of nucleoid organization, which is influenced by a variety of developmental cues and the cell cycle, is also examined.
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Affiliation(s)
- Yoshiki Nishimura
- Department of Botany, Graduate School of Science, Kyoto University, Oiwake-cho, Kita-Shirakawa, Sakyo-ku, Kyoto, 606-8502 Japan
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10
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Chai X, Wang X, Rong L, Luo M, Yuan L, Li Q, He B, Jiang J, Ji D, Ouyang M, Lu Q, Zhang L, Rochaix JD, Chi W. The translocon protein FtsHi1 is an ATP-dependent DNA/RNA helicase that prevents R-loop accumulation in chloroplasts. THE NEW PHYTOLOGIST 2024; 241:2209-2226. [PMID: 38084045 DOI: 10.1111/nph.19470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 11/22/2023] [Indexed: 02/09/2024]
Abstract
R-loops, three-stranded nucleic acid structures consisting of a DNA: RNA hybrid and displaced single-stranded DNA, play critical roles in gene expression and genome stability. How R-loop homeostasis is integrated into chloroplast gene expression remains largely unknown. We found an unexpected function of FtsHi1, an inner envelope membrane-bound AAA-ATPase in chloroplast R-loop homeostasis of Arabidopsis thaliana. Previously, this protein was shown to function as a component of the import motor complex for nuclear-encoded chloroplast proteins. However, this study provides evidence that FtsHi1 is an ATP-dependent helicase that efficiently unwinds both DNA-DNA and DNA-RNA duplexes, thereby preventing R-loop accumulation. Over-accumulation of R-loops could impair chloroplast transcription but not necessarily genome integrity. The dual function of FtsHi1 in both protein import and chloroplast gene expression may be important to coordinate the biogenesis of nuclear- and chloroplast-encoded subunits of multi-protein photosynthetic complexes. This study suggests a mechanical link between protein import and R-loop homeostasis in chloroplasts of higher plants.
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Affiliation(s)
- Xin Chai
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- Artemisinin Research Center, Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, 100700, China
| | - Xiushun Wang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Liwei Rong
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Manfei Luo
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Li Yuan
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qiuxin Li
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Baoye He
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Jingjing Jiang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Daili Ji
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Min Ouyang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Qingtao Lu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Lixin Zhang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, 85 Minglun St., Kaifeng, 475001, China
| | - Jean-David Rochaix
- Department of Molecular Biology, University of Geneva, 1211, Geneva, Switzerland
- Department of Plant Biology, University of Geneva, 1211, Geneva, Switzerland
| | - Wei Chi
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100101, China
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11
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Lucinski R, Dobrogojski J, Ishikawa T, Adamiec M. The role of EGY2 protease in response to high light stress. FUNCTIONAL PLANT BIOLOGY : FPB 2024; 51:FP23243. [PMID: 38190657 DOI: 10.1071/fp23243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 12/14/2023] [Indexed: 01/10/2024]
Abstract
In this study, we investigated the importance of one of the intramembrane proteases, EGY2, for the proper functioning of PSII under short-term high light stress conditions. EGY2 is a chloroplast intramembrane protease of the S2P family, whose absence in Arabidopsis thaliana affects PSII protein composition. The egy2 mutants exhibited a slower degradation of PsbA and decreased content of PsbC and PsbD. During exposure to high light stress, these stoichiometric changes affect the functional state of PSII, leading to its higher sensitivity to photoinhibition of the PSII reaction centre and increased heat dissipation. Furthermore, we explored the relationship between EGY2 and the pTAC16 transcription factor, which is a potential EGY2 substrate. Under light stress, WT plants showed decreased levels of pTAC16, while it remained unchanged in the egy2 mutants. This finding suggests that EGY2 may release pTAC16 from thylakoid membranes through proteolytic cleavage. We also confirmed the physical interaction between EGY2 and pTAC16 using the yeast two-hybrid system, providing evidence of EGY2's involvement in the regulation of PsbA and PsbC/PsbD operons by releasing pTAC16 from the thylakoid membrane.
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Affiliation(s)
- Robert Lucinski
- Adam Mickiewicz University, Faculty of Biology, Institute of Experimental Biology, Department of Plant Physiology, Poznan, Poland
| | - Jedrzej Dobrogojski
- University of Life Sciences, Faculty of Agronomy, Horticulture and Bioengineering, Department of Biochemistry and Biotechnology, Poznan, Poland
| | - Takao Ishikawa
- University of Warsaw, Faculty of Biology, Institute of Microbiology, Department of Environmental Microbiology and Biotechnology, ul. Miecznikowa 1, 02-096 Warszawa, Poland
| | - Malgorzata Adamiec
- Adam Mickiewicz University, Faculty of Biology, Institute of Experimental Biology, Department of Plant Physiology, Poznan, Poland
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12
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Skiada S, Launay-Avon A, Liehrmann A, Delannoy E, Castandet B. The Use of Nanopore Sequencing to Analyze the Chloroplast Transcriptome Part I: Library Preparation. Methods Mol Biol 2024; 2776:243-257. [PMID: 38502509 DOI: 10.1007/978-1-0716-3726-5_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
Global understanding of plastid gene expression has always been impaired by its complexity. RNA splicing, editing, and intercistronic processing create multiple transcripts isoforms that can hardly be resolved using traditional molecular biology techniques. During the last decade, the wide adoption of RNA-seq-based techniques has, however, allowed an unprecedented understanding of all the different steps of chloroplast gene expression, from transcription to translation. Current strategies are nonetheless unable to identify and quantify full length transcripts isoforms, a limitation that can now be overcome using Nanopore Sequencing. We here provide a complete protocol to produce, from total leaf RNA, cDNA libraries ready for Nanopore sequencing. While most Nanopore protocols take advantage of the mRNA polyA tail we here first ligate an RNA adapter to the 3' ends of the RNAs and use it to initiate the template switching reverse transcription. The cDNA is then prepared and indexed for use with the regular Oxford Nanopore v14 chemistry. This protocol is of particular interest to researchers willing to simultaneously study the multiple post-transcriptional processes prevalent in the chloroplast.
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Affiliation(s)
- Sébastien Skiada
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, Gif sur Yvette, France
| | - Alexandra Launay-Avon
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, Gif sur Yvette, France
- Laboratoire de Mathématiques et de Modélisation d'Evry (LaMME), Université d'Evry-Val-d'Essonne, UMR CNRS 8071, ENSIIE, USC INRAE, Evry, France
| | - Arnaud Liehrmann
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, Gif sur Yvette, France
- Laboratoire de Mathématiques et de Modélisation d'Evry (LaMME), Université d'Evry-Val-d'Essonne, UMR CNRS 8071, ENSIIE, USC INRAE, Evry, France
| | - Etienne Delannoy
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, Gif sur Yvette, France
| | - Benoît Castandet
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, Gif sur Yvette, France.
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13
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Zhang L, Braynen J, Fahey A, Chopra K, Cifani P, Tadesse D, Regulski M, Hu F, van Dam HJJ, Xie M, Ware D, Blaby-Haas CE. Two related families of metal transferases, ZNG1 and ZNG2, are involved in acclimation to poor Zn nutrition in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2023; 14:1237722. [PMID: 37965006 PMCID: PMC10642216 DOI: 10.3389/fpls.2023.1237722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 10/02/2023] [Indexed: 11/16/2023]
Abstract
Metal homeostasis has evolved to tightly modulate the availability of metals within the cell, avoiding cytotoxic interactions due to excess and protein inactivity due to deficiency. Even in the presence of homeostatic processes, however, low bioavailability of these essential metal nutrients in soils can negatively impact crop health and yield. While research has largely focused on how plants assimilate metals, acclimation to metal-limited environments requires a suite of strategies that are not necessarily involved in metal transport across membranes. The identification of these mechanisms provides a new opportunity to improve metal-use efficiency and develop plant foodstuffs with increased concentrations of bioavailable metal nutrients. Here, we investigate the function of two distinct subfamilies of the nucleotide-dependent metallochaperones (NMCs), named ZNG1 and ZNG2, that are found in plants, using Arabidopsis thaliana as a reference organism. AtZNG1 (AT1G26520) is an ortholog of human and fungal ZNG1, and like its previously characterized eukaryotic relatives, localizes to the cytosol and physically interacts with methionine aminopeptidase type I (AtMAP1A). Analysis of AtZNG1, AtMAP1A, AtMAP2A, and AtMAP2B transgenic mutants are consistent with the role of Arabidopsis ZNG1 as a Zn transferase for AtMAP1A, as previously described in yeast and zebrafish. Structural modeling reveals a flexible cysteine-rich loop that we hypothesize enables direct transfer of Zn from AtZNG1 to AtMAP1A during GTP hydrolysis. Based on proteomics and transcriptomics, loss of this ancient and conserved mechanism has pleiotropic consequences impacting the expression of hundreds of genes, including those involved in photosynthesis and vesicle transport. Members of the plant-specific family of NMCs, ZNG2A1 (AT1G80480) and ZNG2A2 (AT1G15730), are also required during Zn deficiency, but their target protein(s) remain to be discovered. RNA-seq analyses reveal wide-ranging impacts across the cell when the genes encoding these plastid-localized NMCs are disrupted.
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Affiliation(s)
- Lifang Zhang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States
| | - Janeen Braynen
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States
| | - Audrey Fahey
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States
| | - Kriti Chopra
- Computational Science Initiative, Brookhaven National Laboratory, Upton, NY, United States
| | - Paolo Cifani
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States
| | - Dimiru Tadesse
- Biology Department, Brookhaven National Laboratory, Upton, NY, United States
| | - Michael Regulski
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States
| | - Fangle Hu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States
| | - Hubertus J. J. van Dam
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, United States
| | - Meng Xie
- Biology Department, Brookhaven National Laboratory, Upton, NY, United States
| | - Doreen Ware
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States
- USDA ARS NAA Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, Ithaca, NY, United States
| | - Crysten E. Blaby-Haas
- Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
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14
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Zhang Y, Tian L, Lu C. Chloroplast gene expression: Recent advances and perspectives. PLANT COMMUNICATIONS 2023; 4:100611. [PMID: 37147800 PMCID: PMC10504595 DOI: 10.1016/j.xplc.2023.100611] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 04/11/2023] [Accepted: 05/01/2023] [Indexed: 05/07/2023]
Abstract
Chloroplasts evolved from an ancient cyanobacterial endosymbiont more than 1.5 billion years ago. During subsequent coevolution with the nuclear genome, the chloroplast genome has remained independent, albeit strongly reduced, with its own transcriptional machinery and distinct features, such as chloroplast-specific innovations in gene expression and complicated post-transcriptional processing. Light activates the expression of chloroplast genes via mechanisms that optimize photosynthesis, minimize photodamage, and prioritize energy investments. Over the past few years, studies have moved from describing phases of chloroplast gene expression to exploring the underlying mechanisms. In this review, we focus on recent advances and emerging principles that govern chloroplast gene expression in land plants. We discuss engineering of pentatricopeptide repeat proteins and its biotechnological effects on chloroplast RNA research; new techniques for characterizing the molecular mechanisms of chloroplast gene expression; and important aspects of chloroplast gene expression for improving crop yield and stress tolerance. We also discuss biological and mechanistic questions that remain to be answered in the future.
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Affiliation(s)
- Yi Zhang
- National Key Laboratory of Wheat Improvement, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, China
| | - Lin Tian
- National Key Laboratory of Wheat Improvement, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, China
| | - Congming Lu
- National Key Laboratory of Wheat Improvement, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, China.
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15
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Bhattacharya O, Ortiz I, Hendricks N, Walling LL. The tomato chloroplast stromal proteome compendium elucidated by leveraging a plastid protein-localization prediction Atlas. FRONTIERS IN PLANT SCIENCE 2023; 14:1020275. [PMID: 37701797 PMCID: PMC10493611 DOI: 10.3389/fpls.2023.1020275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 06/22/2023] [Indexed: 09/14/2023]
Abstract
Tomato (Solanum lycopersicum) is a model species for studying fruit development, wounding, herbivory, and pathogen attack. Despite tomato's world-wide economic importance and the role of chloroplasts as metabolic hubs and integrators of environmental cues, little is known about the stromal proteome of tomato. Using a high-yielding protocol for chloroplast and stromal protein isolation, MudPIT nano-LC-MS/MS analyses, a robust in-house protein database (the Atlas) for predicting the plastid localization of tomato proteins, and rigorous selection criteria for inclusion/exclusion in the stromal proteome, we identified 1,278 proteins of the tomato stromal proteome. We provide one of the most robust stromal proteomes available to date with empirical evidence for 545 and 92 proteins not previously described for tomato plastids and the Arabidopsis stroma, respectively. The relative abundance of tomato stromal proteins was determined using the exponentially modified protein abundance index (emPAI). Comparison of the abundance of tomato and Arabidopsis stromal proteomes provided evidence for the species-specific nature of stromal protein homeostasis. The manual curation of the tomato stromal proteome classified proteins into ten functional categories resulting in an accessible compendium of tomato chloroplast proteins. After curation, only 91 proteins remained as unknown, uncharacterized or as enzymes with unknown functions. The curation of the tomato stromal proteins also indicated that tomato has a number of paralogous proteins, not present in Arabidopsis, which accumulated to different levels in chloroplasts. As some of these proteins function in key metabolic pathways or in perceiving or transmitting signals critical for plant adaptation to biotic and abiotic stress, these data suggest that tomato may modulate the bidirectional communication between chloroplasts and nuclei in a novel manner. The stromal proteome provides a fertile ground for future mechanistic studies in the field of tomato chloroplast-nuclear signaling and are foundational for our goal of elucidating the dynamics of the stromal proteome controlled by the solanaceous-specific, stromal, and wound-inducible leucine aminopeptidase A of tomato.
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Affiliation(s)
- Oindrila Bhattacharya
- Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA, United States
| | - Irma Ortiz
- Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA, United States
| | - Nathan Hendricks
- Institute of Integrative Genome Biology, University of California, Riverside, Riverside, CA, United States
| | - Linda L. Walling
- Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA, United States
- Institute of Integrative Genome Biology, University of California, Riverside, Riverside, CA, United States
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16
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Andrade-Marcial M, Ruíz-May E, Elizalde-Contreras JM, Pacheco N, Herrera-Pool E, De-la-Peña C. Proteome of Agave angustifolia Haw.: Uncovering metabolic alterations, over-accumulation of amino acids, and compensatory pathways in chloroplast-deficient albino plantlets. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 201:107902. [PMID: 37506650 DOI: 10.1016/j.plaphy.2023.107902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 07/04/2023] [Accepted: 07/20/2023] [Indexed: 07/30/2023]
Abstract
Amino acids (AA) are essential molecules for plant physiology, acting as precursor molecules for proteins and other organic compounds. Chloroplasts play a vital role in AA metabolism, yet little is known about the impact on AA metabolism of albino plants' lack of chloroplasts. In this study, we conducted a quantitative proteome analysis on albino and variegated somaclonal variants of Agave angustifolia Haw. to investigate metabolic alterations in chloroplast-deficient plants, with a focus on AA metabolic pathways. We identified 82 enzymes involved in AA metabolism, with 32 showing differential accumulation between the somaclonal variants. AaCM, AaALS, AaBCAT, AaIPMS1, AaSHMT, AaAST, AaCGS, and AaMS enzymes were particularly relevant in chloroplast-deficient Agave plantlets. Both variegated and albino phenotypes exhibited excessive synthesis of AA typically associated with chloroplasts (aromatic AAs, BCAAs, Asp, Lys, Pro and Met). Consistent trends were observed for AaBCAT and AaCM at mRNA and protein levels in albino plantlets. These findings highlight the critical activation and reprogramming of AA metabolic pathways in plants lacking chloroplasts. This study contributes to unraveling the intricate relationship between AA metabolism and chloroplast absence, offering insights into survival mechanisms of albino plants.
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Affiliation(s)
- M Andrade-Marcial
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Calle 43 No. 130 x 32 y 34. Col. Chuburná de Hidalgo, 97205, Mérida, Yucatán, México
| | - E Ruíz-May
- Red de Estudios Moleculares Avanzados, Clúster Científico y Tecnológico BioMimic®, Instituto de Ecología A.C. (INECOL), Carretera Antigua a Coatepec No. 351, Congregación el Haya, 91070, Xalapa, Veracruz, México
| | - J M Elizalde-Contreras
- Red de Estudios Moleculares Avanzados, Clúster Científico y Tecnológico BioMimic®, Instituto de Ecología A.C. (INECOL), Carretera Antigua a Coatepec No. 351, Congregación el Haya, 91070, Xalapa, Veracruz, México
| | - N Pacheco
- Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco (CIATEJ), Unidad Sureste, Tablaje Catastral 31264 Km 5.5 Carretera Sierra Papacal-Chuburná Puerto, Parque Científico Tecnológico de Yucatán, CP, 97302, Mérida, Yucatán, México
| | - E Herrera-Pool
- Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco (CIATEJ), Unidad Sureste, Tablaje Catastral 31264 Km 5.5 Carretera Sierra Papacal-Chuburná Puerto, Parque Científico Tecnológico de Yucatán, CP, 97302, Mérida, Yucatán, México
| | - C De-la-Peña
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Calle 43 No. 130 x 32 y 34. Col. Chuburná de Hidalgo, 97205, Mérida, Yucatán, México.
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17
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Small I, Melonek J, Bohne AV, Nickelsen J, Schmitz-Linneweber C. Plant organellar RNA maturation. THE PLANT CELL 2023; 35:1727-1751. [PMID: 36807982 PMCID: PMC10226603 DOI: 10.1093/plcell/koad049] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 01/05/2023] [Accepted: 01/17/2023] [Indexed: 05/30/2023]
Abstract
Plant organellar RNA metabolism is run by a multitude of nucleus-encoded RNA-binding proteins (RBPs) that control RNA stability, processing, and degradation. In chloroplasts and mitochondria, these post-transcriptional processes are vital for the production of a small number of essential components of the photosynthetic and respiratory machinery-and consequently for organellar biogenesis and plant survival. Many organellar RBPs have been functionally assigned to individual steps in RNA maturation, often specific to selected transcripts. While the catalog of factors identified is ever-growing, our knowledge of how they achieve their functions mechanistically is far from complete. This review summarizes the current knowledge of plant organellar RNA metabolism taking an RBP-centric approach and focusing on mechanistic aspects of RBP functions and the kinetics of the processes they are involved in.
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Affiliation(s)
- Ian Small
- Australian Research Council Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Crawley 6009, Australia
| | - Joanna Melonek
- Australian Research Council Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Crawley 6009, Australia
| | | | - Jörg Nickelsen
- Department of Molecular Plant Sciences, LMU Munich, 82152 Martinsried, Germany
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18
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Nair A, Harshith CY, Narjala A, Shivaprasad PV. Begomoviral βC1 orchestrates organellar genomic instability to augment viral infection. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 114:934-950. [PMID: 36919198 DOI: 10.1111/tpj.16186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 03/04/2023] [Accepted: 03/10/2023] [Indexed: 05/27/2023]
Abstract
Chloroplast is the site for transforming light energy to chemical energy. It also acts as a production unit for a variety of defense-related molecules. These defense moieties are necessary to mount a successful counter defense against pathogens, including viruses. Previous studies indicated disruption of chloroplast homeostasis as a basic strategy of Begomovirus for its successful infection leading to the production of vein-clearing, mosaic, and chlorotic symptoms in infected plants. Although begomoviral pathogenicity determinant protein Beta C1 (βC1) was implicated for pathogenicity, the underlying mechanism was unclear. Here we show that, begomoviral βC1 directly interferes with the host plastid homeostasis. βC1 induced DPD1, an organelle-specific nuclease, implicated in nutrient salvage and senescence, as well as modulated the function of a major plastid genome maintainer protein RecA1, to subvert plastid genome. We show that βC1 was able to physically interact with bacterial RecA and its plant homolog RecA1, resulting in its altered activity. We observed that knocking-down DPD1 during virus infection significantly reduced virus-induced necrosis. These results indicate the presence of a strategy in which a viral protein alters host defense by targeting modulators of chloroplast DNA. We predict that the mechanism identified here might have similarities in other plant-pathogen interactions.
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Affiliation(s)
- Ashwin Nair
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bellary Road, Bangalore, 560065, India
- SASTRA University, Thirumalaisamudram, Thanjavur, 613401, India
| | - Chitthavalli Y Harshith
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bellary Road, Bangalore, 560065, India
| | - Anushree Narjala
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bellary Road, Bangalore, 560065, India
- SASTRA University, Thirumalaisamudram, Thanjavur, 613401, India
| | - Padubidri V Shivaprasad
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bellary Road, Bangalore, 560065, India
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19
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Manh MB, Ost C, Peiter E, Hause B, Krupinska K, Humbeck K. WHIRLY1 Acts Upstream of ABA-Related Reprogramming of Drought-Induced Gene Expression in Barley and Affects Stress-Related Histone Modifications. Int J Mol Sci 2023; 24:ijms24076326. [PMID: 37047301 PMCID: PMC10094662 DOI: 10.3390/ijms24076326] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 03/22/2023] [Accepted: 03/24/2023] [Indexed: 03/30/2023] Open
Abstract
WHIRLY1, a small plant-specific ssDNA-binding protein, dually located in chloroplasts and the nucleus, is discussed to act as a retrograde signal transmitting a stress signal from the chloroplast to the nucleus and triggering there a stress-related gene expression. In this work, we investigated the function of WHIRLY1 in the drought stress response of barley, employing two overexpression lines (oeW1-2 and oeW1-15). The overexpression of WHIRLY1 delayed the drought-stress-related onset of senescence in primary leaves. Two abscisic acid (ABA)-dependent marker genes of drought stress, HvNCED1 and HvS40, whose expression in the wild type was induced during drought treatment, were not induced in overexpression lines. In addition, a drought-related increase in ABA concentration in the leaves was suppressed in WHIRLY1 overexpression lines. To analyze the impact of the gain-of-function of WHIRLY1 on the drought-related reprogramming of nuclear gene expression, RNAseq was performed comparing the wild type and an overexpression line. Cluster analyses revealed a set of genes highly up-regulated in response to drought in the wild type but not in the WHIRLY1 overexpression lines. Among these genes were many stress- and abscisic acid (ABA)-related ones. Another cluster comprised genes up-regulated in the oeW1 lines compared to the wild type. These were related to primary metabolism, chloroplast function and growth. Our results indicate that WHIRLY1 acts as a hub, balancing trade-off between stress-related and developmental pathways. To test whether the gain-of-function of WHIRLY1 affects the epigenetic control of stress-related gene expression, we analyzed drought-related histone modifications in different regions of the promoter and at the transcriptional start sites of HvNCED1 and HvS40. Interestingly, the level of euchromatic marks (H3K4me3 and H3K9ac) was clearly decreased in both genes in a WHIRLY1 overexpression line. Our results indicate that WHIRLY1, which is discussed to act as a retrograde signal, affects the ABA-related reprogramming of nuclear gene expression during drought via differential histone modifications.
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Affiliation(s)
- Minh Bui Manh
- Institute of Biology, Martin Luther University Halle-Wittenberg, Weinbergweg 10, 06120 Halle, Germany
| | - Charlotte Ost
- Institute of Biology, Martin Luther University Halle-Wittenberg, Weinbergweg 10, 06120 Halle, Germany
| | - Edgar Peiter
- Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences, Faculty of Natural Sciences III, Martin Luther University Halle-Wittenberg, 06120 Halle, Germany
| | - Bettina Hause
- Department of Cell and Metabolic Biology, Leibniz Institute of Plant Biochemistry, Weinberg 3, 06120 Halle, Germany
| | - Karin Krupinska
- Institute of Botany, Christian-Albrechts-University (CAU), 24098 Kiel, Germany
| | - Klaus Humbeck
- Institute of Biology, Martin Luther University Halle-Wittenberg, Weinbergweg 10, 06120 Halle, Germany
- Correspondence:
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20
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Li Y, Jian Y, Mao Y, Meng F, Shao Z, Wang T, Zheng J, Wang Q, Liu L. "Omics" insights into plastid behavior toward improved carotenoid accumulation. FRONTIERS IN PLANT SCIENCE 2022; 13:1001756. [PMID: 36275568 PMCID: PMC9583013 DOI: 10.3389/fpls.2022.1001756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
Plastids are a group of diverse organelles with conserved carotenoids synthesizing and sequestering functions in plants. They optimize the carotenoid composition and content in response to developmental transitions and environmental stimuli. In this review, we describe the turbulence and reforming of transcripts, proteins, and metabolic pathways for carotenoid metabolism and storage in various plastid types upon organogenesis and external influences, which have been studied using approaches including genomics, transcriptomics, proteomics, and metabonomics. Meanwhile, the coordination of plastid signaling and carotenoid metabolism including the effects of disturbed carotenoid biosynthesis on plastid morphology and function are also discussed. The "omics" insight extends our understanding of the interaction between plastids and carotenoids and provides significant implications for designing strategies for carotenoid-biofortified crops.
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Affiliation(s)
- Yuanyuan Li
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Yue Jian
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Yuanyu Mao
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Fanliang Meng
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Zhiyong Shao
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Tonglin Wang
- Hangzhou Academy of Agricultural Sciences, Hangzhou, China
| | - Jirong Zheng
- Hangzhou Academy of Agricultural Sciences, Hangzhou, China
| | - Qiaomei Wang
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Lihong Liu
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture, Department of Horticulture, Zhejiang University, Hangzhou, China
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21
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Sugita M. An Overview of Pentatricopeptide Repeat (PPR) Proteins in the Moss Physcomitrium patens and Their Role in Organellar Gene Expression. PLANTS 2022; 11:plants11172279. [PMID: 36079663 PMCID: PMC9459714 DOI: 10.3390/plants11172279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 08/29/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022]
Abstract
Pentatricopeptide repeat (PPR) proteins are one type of helical repeat protein that are widespread in eukaryotes. In particular, there are several hundred PPR members in flowering plants. The majority of PPR proteins are localized in the plastids and mitochondria, where they play a crucial role in various aspects of RNA metabolism at the post-transcriptional and translational steps during gene expression. Among the early land plants, the moss Physcomitrium (formerly Physcomitrella) patens has at least 107 PPR protein-encoding genes, but most of their functions remain unclear. To elucidate the functions of PPR proteins, a reverse-genetics approach has been applied to P. patens. To date, the molecular functions of 22 PPR proteins were identified as essential factors required for either mRNA processing and stabilization, RNA splicing, or RNA editing. This review examines the P. patens PPR gene family and their current functional characterization. Similarities and a diversity of functions of PPR proteins between P. patens and flowering plants and their roles in the post-transcriptional regulation of organellar gene expression are discussed.
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Affiliation(s)
- Mamoru Sugita
- Graduate School of Informatics, Nagoya University, Chikusa-ku, Nagoya 464-8601, Japan
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22
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Three-Dimensional Envelope and Subunit Interactions of the Plastid-Encoded RNA Polymerase from Sinapis alba. Int J Mol Sci 2022; 23:ijms23179922. [PMID: 36077319 PMCID: PMC9456514 DOI: 10.3390/ijms23179922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/25/2022] [Accepted: 08/26/2022] [Indexed: 11/16/2022] Open
Abstract
RNA polymerases (RNAPs) are found in all living organisms. In the chloroplasts, the plastid-encoded RNA polymerase (PEP) is a prokaryotic-type multimeric RNAP involved in the selective transcription of the plastid genome. One of its active states requires the assembly of nuclear-encoded PEP-Associated Proteins (PAPs) on the catalytic core, producing a complex of more than 900 kDa, regarded as essential for chloroplast biogenesis. In this study, sequence alignments of the catalytic core subunits across various chloroplasts of the green lineage and prokaryotes combined with structural data show that variations are observed at the surface of the core, whereas internal amino acids associated with the catalytic activity are conserved. A purification procedure compatible with a structural analysis was used to enrich the native PEP from Sinapis alba chloroplasts. A mass spectrometry (MS)-based proteomic analysis revealed the core components, the PAPs and additional proteins, such as FLN2 and pTAC18. MS coupled with crosslinking (XL-MS) provided the initial structural information in the form of protein clusters, highlighting the relative position of some subunits with the surfaces of their interactions. Using negative stain electron microscopy, the PEP three-dimensional envelope was calculated. Particles classification shows that the protrusions are very well-conserved, offering a framework for the future positioning of all the PAPs. Overall, the results show that PEP-associated proteins are firmly and specifically associated with the catalytic core, giving to the plastid transcriptional complex a singular structure compared to other RNAPs.
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23
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Xiong HB, Pan HM, Long QY, Wang ZY, Qu WT, Mei T, Zhang N, Xu XF, Yang ZN, Yu QB. AtNusG, a chloroplast nucleoid protein of bacterial origin linking chloroplast transcriptional and translational machineries, is required for proper chloroplast gene expression in Arabidopsis thaliana. Nucleic Acids Res 2022; 50:6715-6734. [PMID: 35736138 PMCID: PMC9262611 DOI: 10.1093/nar/gkac501] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 05/25/2022] [Accepted: 06/20/2022] [Indexed: 12/24/2022] Open
Abstract
In Escherichia coli, transcription-translation coupling is mediated by NusG. Although chloroplasts are descendants of endosymbiotic prokaryotes, the mechanism underlying this coupling in chloroplasts remains unclear. Here, we report transcription-translation coupling through AtNusG in chloroplasts. AtNusG is localized in chloroplast nucleoids and is closely associated with the chloroplast PEP complex by interacting with its essential component PAP9. It also comigrates with chloroplast ribosomes and interacts with their two components PRPS5 (uS5c) and PRPS10 (uS10c). These data suggest that the transcription and translation machineries are coupled in chloroplasts. In the atnusg mutant, the accumulation of chloroplast-encoded photosynthetic gene transcripts, such as psbA, psbB, psbC and psbD, was not obviously changed, but that of their proteins was clearly decreased. Chloroplast polysomic analysis indicated that the decrease in these proteins was due to the reduced efficiency of their translation in this mutant, leading to reduced photosynthetic efficiency and enhanced sensitivity to cold stress. These data indicate that AtNusG-mediated coupling between transcription and translation in chloroplasts ensures the rapid establishment of photosynthetic capacity for plant growth and the response to environmental changes. Therefore, our study reveals a conserved mechanism of transcription-translation coupling between chloroplasts and E. coli, which perhaps represents a regulatory mechanism of chloroplast gene expression. This study provides insights into the underlying mechanisms of chloroplast gene expression in higher plants.
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Affiliation(s)
| | | | | | - Zi-Yuan Wang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Wan-Tong Qu
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Tong Mei
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Nan Zhang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Xiao-Feng Xu
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Zhong-Nan Yang
- Correspondence may also be addressed to Zhong-Nan Yang. Tel: +86 21 64324650;
| | - Qing-Bo Yu
- To whom correspondence should be addressed. Tel: +86 21 64324812;
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24
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Domb K, Wang N, Hummel G, Liu C. Spatial Features and Functional Implications of Plant 3D Genome Organization. ANNUAL REVIEW OF PLANT BIOLOGY 2022; 73:173-200. [PMID: 35130445 DOI: 10.1146/annurev-arplant-102720-022810] [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] [Indexed: 06/14/2023]
Abstract
The advent of high-throughput sequencing-based methods for chromatin conformation, accessibility, and immunoprecipitation assays has been a turning point in 3D genomics. Altogether, these new tools have been pushing upward the interpretation of pioneer cytogenetic evidence for a higher order in chromatin packing. Here, we review the latest development in our understanding of plant spatial genome structures and different levels of organization and discuss their functional implications. Then, we spotlight the complexity of organellar (i.e., mitochondria and plastids) genomes and discuss their 3D packing into nucleoids. Finally, we propose unaddressed research axes to investigate functional links between chromatin-like dynamics and transcriptional regulation within organellar nucleoids.
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Affiliation(s)
- Katherine Domb
- Institute of Biology, University of Hohenheim, Stuttgart, Germany;
| | - Nan Wang
- Institute of Biology, University of Hohenheim, Stuttgart, Germany;
| | - Guillaume Hummel
- Institute of Biology, University of Hohenheim, Stuttgart, Germany;
| | - Chang Liu
- Institute of Biology, University of Hohenheim, Stuttgart, Germany;
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25
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Wang ZY, Qu WT, Mei T, Zhang N, Yang NY, Xu XF, Xiong HB, Yang ZN, Yu QB. AtRsmD Is Required for Chloroplast Development and Chloroplast Function in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2022; 13:860945. [PMID: 35548310 PMCID: PMC9083416 DOI: 10.3389/fpls.2022.860945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/16/2022] [Indexed: 05/25/2023]
Abstract
AtRsmD was recently demonstrated to be a chloroplast 16S rRNA methyltransferase (MTase) for the m2G915 modification in Arabidopsis. Here, its function of AtRsmD for chloroplast development and photosynthesis was further analyzed. The AtRsmD gene is highly expressed in green photosynthetic tissues. AtRsmD is associated with the thylakoid in chloroplasts. The atrsmd-2 mutant exhibited impaired photosynthetic efficiency in emerging leaves under normal growth conditions. A few thylakoid lamellas could be observed in the chloroplast from the atrsmd-2 mutant, and these thylakoids were loosely organized. Knockout of the AtRsmD gene had minor effects on chloroplast ribosome biogenesis and RNA loading on chloroplast ribosomes, but it reduced the amounts of chloroplast-encoded photosynthesis-related proteins in the emerging leaves, for example, D1, D2, CP43, and CP47, which reduced the accumulation of the photosynthetic complex. Nevertheless, knockout of the AtRsmD gene did not cause a general reduction in chloroplast-encoded proteins in Arabidopsis grown under normal growth conditions. Additionally, the atrsmd-2 mutant exhibited more sensitivity to lincomycin, which specifically inhibits the elongation of nascent polypeptide chains. Cold stress exacerbated the effect on chloroplast ribosome biogenesis in the atrsmd-2 mutant. All these data suggest that the AtRsmD protein plays distinct regulatory roles in chloroplast translation, which is required for chloroplast development and chloroplast function.
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26
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Krupinska K, Desel C, Frank S, Hensel G. WHIRLIES Are Multifunctional DNA-Binding Proteins With Impact on Plant Development and Stress Resistance. FRONTIERS IN PLANT SCIENCE 2022; 13:880423. [PMID: 35528945 PMCID: PMC9070903 DOI: 10.3389/fpls.2022.880423] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 03/24/2022] [Indexed: 06/01/2023]
Abstract
WHIRLIES are plant-specific proteins binding to DNA in plastids, mitochondria, and nucleus. They have been identified as significant components of nucleoids in the organelles where they regulate the structure of the nucleoids and diverse DNA-associated processes. WHIRLIES also fulfil roles in the nucleus by interacting with telomers and various transcription factors, among them members of the WRKY family. While most plants have two WHIRLY proteins, additional WHIRLY proteins evolved by gene duplication in some dicot families. All WHIRLY proteins share a conserved WHIRLY domain responsible for ssDNA binding. Structural analyses revealed that WHIRLY proteins form tetramers and higher-order complexes upon binding to DNA. An outstanding feature is the parallel localization of WHIRLY proteins in two or three cell compartments. Because they translocate from organelles to the nucleus, WHIRLY proteins are excellent candidates for transducing signals between organelles and nucleus to allow for coordinated activities of the different genomes. Developmental cues and environmental factors control the expression of WHIRLY genes. Mutants and plants with a reduced abundance of WHIRLY proteins gave insight into their multiple functionalities. In chloroplasts, a reduction of the WHIRLY level leads to changes in replication, transcription, RNA processing, and DNA repair. Furthermore, chloroplast development, ribosome formation, and photosynthesis are impaired in monocots. In mitochondria, a low level of WHIRLIES coincides with a reduced number of cristae and a low rate of respiration. The WHIRLY proteins are involved in the plants' resistance toward abiotic and biotic stress. Plants with low levels of WHIRLIES show reduced responsiveness toward diverse environmental factors, such as light and drought. Consequently, because such plants are impaired in acclimation, they accumulate reactive oxygen species under stress conditions. In contrast, several plant species overexpressing WHIRLIES were shown to have a higher resistance toward stress and pathogen attacks. By their multiple interactions with organelle proteins and nuclear transcription factors maybe a comma can be inserted here? and their participation in organelle-nucleus communication, WHIRLY proteins are proposed to serve plant development and stress resistance by coordinating processes at different levels. It is proposed that the multifunctionality of WHIRLY proteins is linked to the plasticity of land plants that develop and function in a continuously changing environment.
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Affiliation(s)
- Karin Krupinska
- Institute of Botany, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Christine Desel
- Institute of Botany, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Susann Frank
- Institute of Botany, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Götz Hensel
- Centre for Plant Genome Engineering, Institute of Plant Biochemistry, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
- Centre of Region Haná for Biotechnological and Agricultural Research, Czech Advanced Technology and Research Institute, Palacký University Olomouc, Olomouc, Czechia
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27
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Oetke S, Scheidig AJ, Krupinska K. WHIRLY1 of Barley and Maize Share a PRAPP Motif Conferring Nucleoid Compaction. PLANT & CELL PHYSIOLOGY 2022; 63:234-247. [PMID: 34792609 DOI: 10.1093/pcp/pcab164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 11/01/2021] [Accepted: 11/10/2021] [Indexed: 06/13/2023]
Abstract
WHIRLY1 in barley was shown to be a major architect of plastid nucleoids. Its accumulation in cells of Escherichia coli coincided with an induction of nucleoid compaction and growth retardation. While WHIRLY1 of maize had similar effects on E. coli cells, WHIRLY1 proteins of Arabidopsis and potato as well as WHIRLY2 proteins had no impact on nucleoid compaction in E. coli. By mutagenesis of HvWHIRLY1 the PRAPP motif at the N-terminus preceding the highly conserved WHIRLY domain was identified to be responsible for the nucleoid compacting activity of HvWHIRLY1 in bacteria. This motif is found in WHIRLY1 proteins of most members of the Poaceae family, but neither in the WHIRLY2 proteins of the family nor in any WHIRLY protein of eudicot species such as Arabidopsis thaliana. This finding indicates that a subset of the monocot WHIRLY1 proteins has acquired a specific function as nucleoid compacters by sequence variation in the N-terminal part preceding the conserved WHIRLY domain and that in different groups of higher plants the compaction of nucleoids is mediated by other proteins.
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Affiliation(s)
- Svenja Oetke
- Institute of Botany, Christian-Albrechts-University of Kiel, Am Botanischen Garten 7, 24118 Kiel, Germany
| | - Axel J Scheidig
- Institute of Zoology, Christian-Albrechts-University of Kiel, Am Botanischen Garten 7, 24118 Kiel, Germany
| | - Karin Krupinska
- Institute of Botany, Christian-Albrechts-University of Kiel, Am Botanischen Garten 7, 24118 Kiel, Germany
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28
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Hooper CM, Castleden IR, Tanz SK, Grasso SV, Millar AH. Subcellular Proteomics as a Unified Approach of Experimental Localizations and Computed Prediction Data for Arabidopsis and Crop Plants. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1346:67-89. [PMID: 35113396 DOI: 10.1007/978-3-030-80352-0_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In eukaryotic organisms, subcellular protein location is critical in defining protein function and understanding sub-functionalization of gene families. Some proteins have defined locations, whereas others have low specificity targeting and complex accumulation patterns. There is no single approach that can be considered entirely adequate for defining the in vivo location of all proteins. By combining evidence from different approaches, the strengths and weaknesses of different technologies can be estimated, and a location consensus can be built. The Subcellular Location of Proteins in Arabidopsis database ( http://suba.live/ ) combines experimental data sets that have been reported in the literature and is analyzing these data to provide useful tools for biologists to interpret their own data. Foremost among these tools is a consensus classifier (SUBAcon) that computes a proposed location for all proteins based on balancing the experimental evidence and predictions. Further tools analyze sets of proteins to define the abundance of cellular structures. Extending these types of resources to plant crop species has been complex due to polyploidy, gene family expansion and contraction, and the movement of pathways and processes within cells across the plant kingdom. The Crop Proteins of Annotated Location database ( http://crop-pal.org/ ) has developed a range of subcellular location resources including a species-specific voting consensus for 12 plant crop species that offers collated evidence and filters for current crop proteomes akin to SUBA. Comprehensive cross-species comparison of these data shows that the sub-cellular proteomes (subcellulomes) depend only to some degree on phylogenetic relationship and are more conserved in major biosynthesis than in metabolic pathways. Together SUBA and cropPAL created reference subcellulomes for plants as well as species-specific subcellulomes for cross-species data mining. These data collections are increasingly used by the research community to provide a subcellular protein location layer, inform models of compartmented cell function and protein-protein interaction network, guide future molecular crop breeding strategies, or simply answer a specific question-where is my protein of interest inside the cell?
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Affiliation(s)
- Cornelia M Hooper
- The Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley, WA, Australia
| | - Ian R Castleden
- The Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley, WA, Australia
| | - Sandra K Tanz
- The Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley, WA, Australia
| | - Sally V Grasso
- The Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley, WA, Australia
| | - A Harvey Millar
- The Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley, WA, Australia.
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29
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Wang W, Cheng L, Sun Q. Chromatin Immunoprecipitation in Chloroplasts. Curr Protoc 2022; 2:e360. [PMID: 35077029 DOI: 10.1002/cpz1.360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Chromatin is the genetic material assembled by nucleic acids (including DNA and RNA) and proteins. The biological functions of chromatin are highly dependent on the interaction between DNA (and/or RNA) and proteins that bind to it. Chromatin immunoprecipitation (ChIP) is a powerful technique for evaluating these interactions and has been widely used to characterize the functions of nuclear proteins. However, its application in identifying plant organellar chromatin-binding proteins is lagging. This article describes the method for analyzing the association of chloroplast-localized proteins with the chloroplast genome. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Chloroplast isolation Basic Protocol 2: Crosslinking of DNA-Protein complexes Basic Protocol 3: Chromatin isolation and preparation Support Protocol: Bead-antibody complex preparation Basic Protocol 4: Immunoprecipitation and washes Basic Protocol 5: DNA preparation Basic Protocol 6: Analysis of results.
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Affiliation(s)
- Wenjie Wang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Lingling Cheng
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Qianwen Sun
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
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30
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Rei Liao JY, Friso G, Forsythe ES, Michel EJS, Williams AM, Boguraev SS, Ponnala L, Sloan DB, van Wijk KJ. Proteomics, phylogenetics, and co-expression analyses indicate novel interactions in the plastid CLP chaperone-protease system. J Biol Chem 2022; 298:101609. [PMID: 35065075 PMCID: PMC8889267 DOI: 10.1016/j.jbc.2022.101609] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 01/13/2022] [Accepted: 01/16/2022] [Indexed: 12/20/2022] Open
Abstract
The chloroplast chaperone CLPC1 unfolds and delivers substrates to the stromal CLPPRT protease complex for degradation. We previously used an in vivo trapping approach to identify interactors with CLPC1 in Arabidopsis thaliana by expressing a STREPII-tagged copy of CLPC1 mutated in its Walker B domains (CLPC1-TRAP) followed by affinity purification and mass spectrometry. To create a larger pool of candidate substrates, adaptors, or regulators, we carried out a far more sensitive and comprehensive in vivo protein trapping analysis. We identified 59 highly enriched CLPC1 protein interactors, in particular proteins belonging to families of unknown functions (DUF760, DUF179, DUF3143, UVR-DUF151, HugZ/DUF2470), as well as the UVR domain proteins EXE1 and EXE2 implicated in singlet oxygen damage and signaling. Phylogenetic and functional domain analyses identified other members of these families that appear to localize (nearly) exclusively to plastids. In addition, several of these DUF proteins are of very low abundance as determined through the Arabidopsis PeptideAtlas http://www.peptideatlas.org/builds/arabidopsis/ showing that enrichment in the CLPC1-TRAP was extremely selective. Evolutionary rate covariation indicated that the HugZ/DUF2470 family coevolved with the plastid CLP machinery suggesting functional and/or physical interactions. Finally, mRNA-based coexpression networks showed that all 12 CLP protease subunits tightly coexpressed as a single cluster with deep connections to DUF760-3. Coexpression modules for other trapped proteins suggested specific functions in biological processes, e.g., UVR2 and UVR3 were associated with extraplastidic degradation, whereas DUF760-6 is likely involved in senescence. This study provides a strong foundation for discovery of substrate selection by the chloroplast CLP protease system.
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Affiliation(s)
- Jui-Yun Rei Liao
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, New York, USA
| | - Giulia Friso
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, New York, USA
| | - Evan S Forsythe
- Graduate Program in Cell and Molecular Biology, Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Elena J S Michel
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, New York, USA
| | - Alissa M Williams
- Graduate Program in Cell and Molecular Biology, Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Sasha S Boguraev
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, New York, USA
| | | | - Daniel B Sloan
- Graduate Program in Cell and Molecular Biology, Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Klaas J van Wijk
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, New York, USA.
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31
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Yang Z, Liu M, Ding S, Zhang Y, Yang H, Wen X, Chi W, Lu C, Lu Q. Plastid Deficient 1 Is Essential for the Accumulation of Plastid-Encoded RNA Polymerase Core Subunit β and Chloroplast Development in Arabidopsis. Int J Mol Sci 2021; 22:ijms222413648. [PMID: 34948448 PMCID: PMC8705867 DOI: 10.3390/ijms222413648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/13/2021] [Accepted: 12/16/2021] [Indexed: 12/05/2022] Open
Abstract
Plastid-encoded RNA polymerase (PEP)-dependent transcription is an essential process for chloroplast development and plant growth. It is a complex event that is regulated by numerous nuclear-encoded proteins. In order to elucidate the complex regulation mechanism of PEP activity, identification and characterization of PEP activity regulation factors are needed. Here, we characterize Plastid Deficient 1 (PD1) as a novel regulator for PEP-dependent gene expression and chloroplast development in Arabidopsis. The PD1 gene encodes a protein that is conserved in photoautotrophic organisms. The Arabidopsis pd1 mutant showed albino and seedling-lethal phenotypes. The plastid development in the pd1 mutant was arrested. The PD1 protein localized in the chloroplasts, and it colocalized with nucleoid protein TRXz. RT-quantitative real-time PCR, northern blot, and run-on analyses indicated that the PEP-dependent transcription in the pd1 mutant was dramatically impaired, whereas the nuclear-encoded RNA polymerase-dependent transcription was up-regulated. The yeast two-hybrid assays and coimmunoprecipitation experiments showed that the PD1 protein interacts with PEP core subunit β (PEP-β), which has been verified to be essential for chloroplast development. The immunoblot analysis indicated that the accumulation of PEP-β was barely detected in the pd1 mutant, whereas the accumulation of the other essential components of the PEP complex, such as core subunits α and β′, were not affected in the pd1 mutant. These observations suggested that the PD1 protein is essential for the accumulation of PEP-β and chloroplast development in Arabidopsis, potentially by direct interaction with PEP-β.
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Affiliation(s)
- Zhipan Yang
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; (Z.Y.); (M.L.); (S.D.); (H.Y.); (X.W.); (W.C.)
| | - Mingxin Liu
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; (Z.Y.); (M.L.); (S.D.); (H.Y.); (X.W.); (W.C.)
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shunhua Ding
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; (Z.Y.); (M.L.); (S.D.); (H.Y.); (X.W.); (W.C.)
| | - Yi Zhang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian 271018, China;
| | - Huixia Yang
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; (Z.Y.); (M.L.); (S.D.); (H.Y.); (X.W.); (W.C.)
| | - Xiaogang Wen
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; (Z.Y.); (M.L.); (S.D.); (H.Y.); (X.W.); (W.C.)
| | - Wei Chi
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; (Z.Y.); (M.L.); (S.D.); (H.Y.); (X.W.); (W.C.)
| | - Congming Lu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian 271018, China;
- Correspondence: (C.L.); (Q.L.)
| | - Qingtao Lu
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; (Z.Y.); (M.L.); (S.D.); (H.Y.); (X.W.); (W.C.)
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
- Correspondence: (C.L.); (Q.L.)
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32
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Kim M, Schulz V, Brings L, Schoeller T, Kühn K, Vierling E. mTERF18 and ATAD3 are required for mitochondrial nucleoid structure and their disruption confers heat tolerance in Arabidopsis thaliana. THE NEW PHYTOLOGIST 2021; 232:2026-2042. [PMID: 34482561 DOI: 10.1111/nph.17717] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/23/2021] [Indexed: 05/27/2023]
Abstract
Mitochondria play critical roles in generating ATP through oxidative phosphorylation (OXPHOS) and produce both damaging and signaling reactive oxygen species (ROS). They have reduced genomes that encode essential subunits of the OXPHOS machinery. Mitochondrial Transcription tERmination Factor-related (mTERF) proteins are involved in organelle gene expression, interacting with organellar DNA or RNA. We previously found that mutations in Arabidopsis thaliana mTERF18/SHOT1 enable plants to better tolerate heat and oxidative stresses, presumably due to low ROS production and reduced oxidative damage. Here we discover that shot1 mutants have greatly reduced OXPHOS complexes I and IV and reveal that suppressor of hot1-4 1 (SHOT1) binds DNA and localizes to mitochondrial nucleoids, which are disrupted in shot1. Furthermore, three homologues of animal ATPase family AAA domain-containing protein 3 (ATAD3), which is involved in mitochondrial nucleoid organization, were identified as SHOT1-interacting proteins. Importantly, disrupting ATAD3 function disrupts nucleoids, reduces accumulation of complex I, and enhances heat tolerance, as is seen in shot1 mutants. Our data link nucleoid organization to OXPHOS biogenesis and suggest that the common defects in shot1 mutants and ATAD3-disrupted plants lead to critical changes in mitochondrial metabolism and signaling that result in plant heat tolerance.
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Affiliation(s)
- Minsoo Kim
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA, 01003, USA
| | - Vincent Schulz
- Department of Life Sciences, Institute of Biology, Humboldt-Universität zu Berlin, 10099, Berlin, Germany
| | - Lea Brings
- Department of Life Sciences, Institute of Biology, Humboldt-Universität zu Berlin, 10099, Berlin, Germany
| | - Theresa Schoeller
- Department of Plant Physiology, Institute of Biology, Martin-Luther-Universität Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Kristina Kühn
- Department of Life Sciences, Institute of Biology, Humboldt-Universität zu Berlin, 10099, Berlin, Germany
- Department of Plant Physiology, Institute of Biology, Martin-Luther-Universität Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Elizabeth Vierling
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA, 01003, USA
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Yamamoto H, Sato N, Shikanai T. Critical Role of NdhA in the Incorporation of the Peripheral Arm into the Membrane-Embedded Part of the Chloroplast NADH Dehydrogenase-Like Complex. PLANT & CELL PHYSIOLOGY 2021; 62:1131-1145. [PMID: 33169158 DOI: 10.1093/pcp/pcaa143] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 10/19/2020] [Indexed: 06/11/2023]
Abstract
The chloroplast NADH dehydrogenase-like (NDH) complex mediates ferredoxin-dependent plastoquinone reduction in the thylakoid membrane. In angiosperms, chloroplast NDH is composed of five subcomplexes and further forms a supercomplex with photosystem I (PSI). Subcomplex A (SubA) mediates the electron transport and consists of eight subunits encoded by both plastid and nuclear genomes. The assembly of SubA in the stroma has been extensively studied, but it is unclear how SubA is incorporated into the membrane-embedded part of the NDH complex. Here, we isolated a novel Arabidopsis mutant chlororespiratory reduction 16 (crr16) defective in NDH activity. CRR16 encodes a chloroplast-localized P-class pentatricopeptide repeat protein conserved in angiosperms. Transcript analysis of plastid-encoded ndh genes indicated that CRR16 was responsible for the efficient splicing of the group II intron in the ndhA transcript, which encodes a membrane-embedded subunit localized to the connecting site between SubA and the membrane subcomplex (SubM). To analyze the roles of NdhA in the assembly and stability of the NDH complex, the homoplastomic knockout plant of ndhA (ΔndhA) was generated in tobacco (Nicotiana tabacum). Biochemical analyses of crr16 and ΔndhA plants indicated that NdhA was essential for stabilizing SubA and SubE but not for the accumulation of the other three subcomplexes. Furthermore, the crr16 mutant accumulated the SubA assembly intermediates in the stroma more than that in the wild type. These results suggest that NdhA biosynthesis is essential for the incorporation of SubA into the membrane-embedded part of the NDH complex at the final assembly step of the NDH-PSI supercomplex.
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Affiliation(s)
- Hiroshi Yamamoto
- Department of Botany, Graduate School of Science, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto, 606-8502 Japan
| | - Nozomi Sato
- Department of Botany, Graduate School of Science, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto, 606-8502 Japan
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo Motoyama, Kita-ku, Kyoto 603-8555, Japan
| | - Toshiharu Shikanai
- Department of Botany, Graduate School of Science, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto, 606-8502 Japan
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Guilcher M, Liehrmann A, Seyman C, Blein T, Rigaill G, Castandet B, Delannoy E. Full Length Transcriptome Highlights the Coordination of Plastid Transcript Processing. Int J Mol Sci 2021; 22:ijms222011297. [PMID: 34681956 PMCID: PMC8537030 DOI: 10.3390/ijms222011297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 10/08/2021] [Accepted: 10/11/2021] [Indexed: 11/29/2022] Open
Abstract
Plastid gene expression involves many post-transcriptional maturation steps resulting in a complex transcriptome composed of multiple isoforms. Although short-read RNA-Seq has considerably improved our understanding of the molecular mechanisms controlling these processes, it is unable to sequence full-length transcripts. This information is crucial, however, when it comes to understanding the interplay between the various steps of plastid gene expression. Here, we describe a protocol to study the plastid transcriptome using nanopore sequencing. In the leaf of Arabidopsis thaliana, with about 1.5 million strand-specific reads mapped to the chloroplast genome, we could recapitulate most of the complexity of the plastid transcriptome (polygenic transcripts, multiple isoforms associated with post-transcriptional processing) using virtual Northern blots. Even if the transcripts longer than about 2500 nucleotides were missing, the study of the co-occurrence of editing and splicing events identified 42 pairs of events that were not occurring independently. This study also highlighted a preferential chronology of maturation events with splicing happening after most sites were edited.
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Affiliation(s)
- Marine Guilcher
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, 91405 Orsay, France; (M.G.); (A.L.); (T.B.); (G.R.); (B.C.)
- Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, CNRS, INRAE, 91405 Orsay, France
| | - Arnaud Liehrmann
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, 91405 Orsay, France; (M.G.); (A.L.); (T.B.); (G.R.); (B.C.)
- Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, CNRS, INRAE, 91405 Orsay, France
- Laboratoire de Mathématiques et de Modélisation d’Evry (LaMME), Université d’Evry-Val-d’Essonne, UMR CNRS 8071, ENSIIE, USC INRAE, 91000 Evry, France;
| | - Chloé Seyman
- Laboratoire de Mathématiques et de Modélisation d’Evry (LaMME), Université d’Evry-Val-d’Essonne, UMR CNRS 8071, ENSIIE, USC INRAE, 91000 Evry, France;
| | - Thomas Blein
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, 91405 Orsay, France; (M.G.); (A.L.); (T.B.); (G.R.); (B.C.)
- Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, CNRS, INRAE, 91405 Orsay, France
| | - Guillem Rigaill
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, 91405 Orsay, France; (M.G.); (A.L.); (T.B.); (G.R.); (B.C.)
- Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, CNRS, INRAE, 91405 Orsay, France
- Laboratoire de Mathématiques et de Modélisation d’Evry (LaMME), Université d’Evry-Val-d’Essonne, UMR CNRS 8071, ENSIIE, USC INRAE, 91000 Evry, France;
| | - Benoit Castandet
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, 91405 Orsay, France; (M.G.); (A.L.); (T.B.); (G.R.); (B.C.)
- Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, CNRS, INRAE, 91405 Orsay, France
| | - Etienne Delannoy
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, 91405 Orsay, France; (M.G.); (A.L.); (T.B.); (G.R.); (B.C.)
- Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, CNRS, INRAE, 91405 Orsay, France
- Correspondence:
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Chen J, Wang L, Jin X, Wan J, Zhang L, Je BI, Zhao K, Kong F, Huang J, Tian M. Oryza sativa ObgC1 Acts as a Key Regulator of DNA Replication and Ribosome Biogenesis in Chloroplast Nucleoids. RICE (NEW YORK, N.Y.) 2021; 14:65. [PMID: 34251486 PMCID: PMC8275814 DOI: 10.1186/s12284-021-00498-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Accepted: 05/30/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND The Spo0B-associated GTP-binding protein (Obg) GTPase, has diverse and important functions in bacteria, including morphological development, DNA replication and ribosome maturation. Homologs of the Bacillus subtilis Obg have been also found in chloroplast of Oryza sativa, but their primary roles remain unknown. RESULTS We clarify that OsObgC1 is a functional homolog of AtObgC. The mutant obgc1-d1 exhibited hypersensitivity to the DNA replication inhibitor hydroxyurea. Quantitative PCR results showed that the ratio of chloroplast DNA to nuclear DNA in the mutants was higher than that of the wild-type plants. After DAPI staining, OsObgC1 mutants showed abnormal nucleoid architectures. The specific punctate staining pattern of OsObgC1-GFP signal suggests that this protein localizes to the chloroplast nucleoids. Furthermore, loss-of-function mutation in OsObgC1 led to a severe suppression of protein biosynthesis by affecting plastid rRNA processing. It was also demonstrated through rRNA profiling that plastid rRNA processing was decreased in obgc1-d mutants, which resulted in impaired ribosome biogenesis. The sucrose density gradient profiles revealed a defective chloroplast ribosome maturation of obgc1-d1 mutants. CONCLUSION Our findings here indicate that the OsObgC1 retains the evolutionarily biological conserved roles of prokaryotic Obg, which acts as a signaling hub that regulates DNA replication and ribosome biogenesis in chloroplast nucleoids.
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Affiliation(s)
- Ji Chen
- College of Agronomy, Sichuan Agricultural University, Chengdu, 611130, China
- Division of Applied Life Sciences (BK21+), Graduate School of Gyeongsang National University, Jinju, 660-701, Republic of Korea
| | - Li Wang
- College of Agronomy, Sichuan Agricultural University, Chengdu, 611130, China
| | - Xiaowan Jin
- College of Agronomy, Sichuan Agricultural University, Chengdu, 611130, China
| | - Jian Wan
- College of Agronomy, Sichuan Agricultural University, Chengdu, 611130, China
| | - Lang Zhang
- College of Agronomy, Sichuan Agricultural University, Chengdu, 611130, China
| | - Byoung Il Je
- College of Ecology and Environment, Chengdu University of Technology, Chengdu, 61005, China
| | - Ke Zhao
- College of Agronomy, Sichuan Agricultural University, Chengdu, 611130, China
| | - Fanlei Kong
- College of Agronomy, Sichuan Agricultural University, Chengdu, 611130, China
| | - Jin Huang
- Division of Applied Life Sciences (BK21+), Graduate School of Gyeongsang National University, Jinju, 660-701, Republic of Korea.
- College of Ecology and Environment, Chengdu University of Technology, Chengdu, 61005, China.
| | - Mengliang Tian
- Institute for New Rural Development, Sichuan Agricultural University, Yaan, 625000, China.
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Chen Y, Wang Y, Yang J, Zhou W, Dai S. Exploring the diversity of plant proteome. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:1197-1210. [PMID: 33650765 DOI: 10.1111/jipb.13087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 02/25/2021] [Indexed: 05/10/2023]
Abstract
The tremendous functional, spatial, and temporal diversity of the plant proteome is regulated by multiple factors that continuously modify protein abundance, modifications, interactions, localization, and activity to meet the dynamic needs of plants. Dissecting the proteome complexity and its underlying genetic variation is attracting increasing research attention. Mass spectrometry (MS)-based proteomics has become a powerful approach in the global study of protein functions and their relationships on a systems level. Here, we review recent breakthroughs and strategies adopted to unravel the diversity of the proteome, with a specific focus on the methods used to analyze posttranslational modifications (PTMs), protein localization, and the organization of proteins into functional modules. We also consider PTM crosstalk and multiple PTMs temporally regulating the life cycle of proteins. Finally, we discuss recent quantitative studies using MS to measure protein turnover rates and examine future directions in the study of the plant proteome.
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Affiliation(s)
- Yanmei Chen
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Yi Wang
- State Key Laboratory of Wheat and Maize Crop Science, College of Resources and Environment, Henan Agricultural University, Zhengzhou, 450002, China
| | - Jun Yang
- Shanghai Key Laboratory of Plant Functional Genomics and Resources, Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Shanghai Chenshan Botanical Garden, Shanghai, 201602, China
| | - Wenbin Zhou
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Shaojun Dai
- Development Center of Plant Germplasm Resources, College of Life Sciences, Shanghai Normal University, Shanghai, 200234, China
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Manavski N, Mathieu S, Rojas M, Méteignier LV, Brachmann A, Barkan A, Hammani K. In vivo stabilization of endogenous chloroplast RNAs by customized artificial pentatricopeptide repeat proteins. Nucleic Acids Res 2021; 49:5985-5997. [PMID: 34037778 PMCID: PMC8191804 DOI: 10.1093/nar/gkab390] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 04/05/2021] [Accepted: 04/28/2021] [Indexed: 12/17/2022] Open
Abstract
Pentatricopeptide repeat (PPR) proteins are helical repeat-proteins that bind RNA in a modular fashion with a sequence-specificity that can be manipulated by the use of an amino acid code. As such, PPR repeats are promising scaffolds for the design of RNA binding proteins for synthetic biology applications. However, the in vivo functional capabilities of artificial PPR proteins built from consensus PPR motifs are just starting to be explored. Here, we report in vivo functions of an artificial PPR protein, dPPRrbcL, made of consensus PPR motifs that were designed to bind a sequence near the 5′ end of rbcL transcripts in Arabidopsis chloroplasts. We used a functional complementation assay to demonstrate that this protein bound its intended RNA target with specificity in vivo and that it substituted for a natural PPR protein by stabilizing processed rbcL mRNA. We targeted a second protein of analogous design to the petL 5′ UTR, where it substituted for the native stabilizing PPR protein PGR3, albeit inefficiently. These results showed that artificial PPR proteins can be engineered to functionally mimic the class of native PPR proteins that serve as physical barriers against exoribonucleases.
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Affiliation(s)
- Nikolay Manavski
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg, France
| | - Sébastien Mathieu
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg, France
| | - Margarita Rojas
- Institute of Molecular Biology, University of Oregon, Eugene, OR 97403 USA
| | - Louis-Valentin Méteignier
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg, France
| | - Andreas Brachmann
- Genetics, Faculty of Biology, Ludwig-Maximilians-University Munich, 82152 Planegg-Martinsried Germany
| | - Alice Barkan
- Institute of Molecular Biology, University of Oregon, Eugene, OR 97403 USA
| | - Kamel Hammani
- To whom correspondence should be addressed. Tel: +33 367155281; Fax: +33 367155300;
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HBD1 protein with a tandem repeat of two HMG-box domains is a DNA clip to organize chloroplast nucleoids in Chlamydomonas reinhardtii. Proc Natl Acad Sci U S A 2021; 118:2021053118. [PMID: 33975946 PMCID: PMC8157925 DOI: 10.1073/pnas.2021053118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Compaction of bulky DNA is a universal issue for all DNA-based life forms. Chloroplast nucleoids (chloroplast DNA-protein complexes) are critical for chloroplast DNA maintenance and transcription, thereby supporting photosynthesis, but their detailed structure remains enigmatic. Our proteomic analysis of chloroplast nucleoids of the green alga Chlamydomonas reinhardtii identified a protein (HBD1) with a tandem repeat of two DNA-binding high mobility group box (HMG-box) domains, which is structurally similar to major mitochondrial nucleoid proteins transcription factor A, mitochondrial (TFAM), and ARS binding factor 2 protein (Abf2p). Disruption of the HBD1 gene by CRISPR-Cas9-mediated genome editing resulted in the scattering of chloroplast nucleoids. This phenotype was complemented when intact HBD1 was reintroduced, whereas a truncated HBD1 with a single HMG-box domain failed to complement the phenotype. Furthermore, ectopic expression of HBD1 in the mitochondria of yeast Δabf2 mutant successfully complemented the defects, suggesting functional similarity between HBD1 and Abf2p. Furthermore, in vitro assays of HBD1, including the electrophoretic mobility shift assay and DNA origami/atomic force microscopy, showed that HBD1 is capable of introducing U-turns and cross-strand bridges, indicating that proteins with two HMG-box domains would function as DNA clips to compact DNA in both chloroplast and mitochondrial nucleoids.
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Sanjaya A, Kazama Y, Ishii K, Muramatsu R, Kanamaru K, Ohbu S, Abe T, Fujiwara MT. An Argon-Ion-Induced Pale Green Mutant of Arabidopsis Exhibiting Rapid Disassembly of Mesophyll Chloroplast Grana. PLANTS (BASEL, SWITZERLAND) 2021; 10:848. [PMID: 33922223 PMCID: PMC8145761 DOI: 10.3390/plants10050848] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/18/2021] [Accepted: 04/21/2021] [Indexed: 01/13/2023]
Abstract
Argon-ion beam is an effective mutagen capable of inducing a variety of mutation types. In this study, an argon ion-induced pale green mutant of Arabidopsis thaliana was isolated and characterized. The mutant, designated Ar50-33-pg1, exhibited moderate defects of growth and greening and exhibited rapid chlorosis in photosynthetic tissues. Fluorescence microscopy confirmed that mesophyll chloroplasts underwent substantial shrinkage during the chlorotic process. Genetic and whole-genome resequencing analyses revealed that Ar50-33-pg1 contained a large 940 kb deletion in chromosome V that encompassed more than 100 annotated genes, including 41 protein-coding genes such as TYRAAt1/TyrA1, EGY1, and MBD12. One of the deleted genes, EGY1, for a thylakoid membrane-localized metalloprotease, was the major contributory gene responsible for the pale mutant phenotype. Both an egy1 mutant and F1 progeny of an Ar50-33-pg1 × egy1 cross-exhibited chlorotic phenotypes similar to those of Ar50-33-pg1. Furthermore, ultrastructural analysis of mesophyll cells revealed that Ar50-33-pg1 and egy1 initially developed wild type-like chloroplasts, but these were rapidly disassembled, resulting in thylakoid disorganization and fragmentation, as well as plastoglobule accumulation, as terminal phenotypes. Together, these data support the utility of heavy-ion mutagenesis for plant genetic analysis and highlight the importance of EGY1 in the structural maintenance of grana in mesophyll chloroplasts.
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Affiliation(s)
- Alvin Sanjaya
- Faculty of Science and Technology, Sophia University, 7-1 Kioicho, Chiyoda, Tokyo 102-8554, Japan; (A.S.); (R.M.)
| | - Yusuke Kazama
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (K.I.); (S.O.); (T.A.)
- Faculty of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Matsuoka-Kenjojima, Eiheiji, Yoshida, Fukui 910-1195, Japan
| | - Kotaro Ishii
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (K.I.); (S.O.); (T.A.)
| | - Ryohsuke Muramatsu
- Faculty of Science and Technology, Sophia University, 7-1 Kioicho, Chiyoda, Tokyo 102-8554, Japan; (A.S.); (R.M.)
| | - Kengo Kanamaru
- Faculty of Agriculture, Kobe University, Nada, Kobe, Hyogo 657-8501, Japan;
| | - Sumie Ohbu
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (K.I.); (S.O.); (T.A.)
| | - Tomoko Abe
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (K.I.); (S.O.); (T.A.)
| | - Makoto T. Fujiwara
- Faculty of Science and Technology, Sophia University, 7-1 Kioicho, Chiyoda, Tokyo 102-8554, Japan; (A.S.); (R.M.)
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (K.I.); (S.O.); (T.A.)
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Xu C, Shen Y, Li C, Lu F, Zhang MD, Meeley RB, McCarty DR, Tan BC. Emb15 encodes a plastid ribosomal assembly factor essential for embryogenesis in maize. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:214-227. [PMID: 33450100 DOI: 10.1111/tpj.15160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 01/06/2021] [Accepted: 01/08/2021] [Indexed: 06/12/2023]
Abstract
Ribosome assembly factors guide the complex process by which ribosomal proteins and the ribosomal RNAs form a functional ribosome. However, the assembly of plant plastid ribosomes is poorly understood. In the present study, we discovered a maize (Zea mays) plastid ribosome assembly factor based on our characterization of the embryo defective 15 (emb15) mutant. Loss of function of Emb15 retards embryo development at an early stage, but does not substantially affect the endosperm, and causes an albino phenotype in other genetic backgrounds. EMB15 localizes to plastids and possesses a ribosome maturation factor M (RimM) domain in the N-terminus and a predicted UDP-GlcNAc pyrophosphorylase domain in the C-terminus. The EMB15 RimM domain originated in bacteria and the UDP-GlcNAc pyrophosphorylase domain originated in fungi; these two domains came together in the ancestor of land plants during evolution. The N-terminus of EMB15 complemented the growth defect of an Escherichia coli strain with a RimM deletion and rescued the albino phenotype of emb15 homozygous mutants. The RimM domain mediates the interaction between EMB15 and the plastid ribosomal protein PRPS19. Plastid 16S rRNA maturation is also significantly impaired in emb15. These observations suggest that EMB15 functions in maize seed development as a plastid ribosome assembly factor, and the C-terminal domain is not important under normal conditions.
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Affiliation(s)
- Chunhui Xu
- Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao Campus, Qingdao, 266237, China
| | - Yun Shen
- Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao Campus, Qingdao, 266237, China
| | - Cuiling Li
- Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao Campus, Qingdao, 266237, China
| | - Fan Lu
- Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao Campus, Qingdao, 266237, China
| | - Meng-Di Zhang
- Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao Campus, Qingdao, 266237, China
| | - Robert B Meeley
- DuPont Pioneer AgBiotech Research, Johnston, Iowa, 50131-1004, USA
| | - Donald R McCarty
- Horticultural Sciences Department, University of Florida, Gainesville, FL, 32611, USA
| | - Bao-Cai Tan
- Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao Campus, Qingdao, 266237, China
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Méteignier LV, Ghandour R, Zimmerman A, Kuhn L, Meurer J, Zoschke R, Hammani K. Arabidopsis mTERF9 protein promotes chloroplast ribosomal assembly and translation by establishing ribonucleoprotein interactions in vivo. Nucleic Acids Res 2021; 49:1114-1132. [PMID: 33398331 PMCID: PMC7826268 DOI: 10.1093/nar/gkaa1244] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 12/07/2020] [Accepted: 12/13/2020] [Indexed: 12/13/2022] Open
Abstract
The mitochondrial transcription termination factor proteins are nuclear-encoded nucleic acid binders defined by degenerate tandem helical-repeats of ∼30 amino acids. They are found in metazoans and plants where they localize in organelles. In higher plants, the mTERF family comprises ∼30 members and several of these have been linked to plant development and response to abiotic stress. However, knowledge of the molecular basis underlying these physiological effects is scarce. We show that the Arabidopsis mTERF9 protein promotes the accumulation of the 16S and 23S rRNAs in chloroplasts, and interacts predominantly with the 16S rRNA in vivo and in vitro. Furthermore, mTERF9 is found in large complexes containing ribosomes and polysomes in chloroplasts. The comprehensive analysis of mTERF9 in vivo protein interactome identified many subunits of the 70S ribosome whose assembly is compromised in the null mterf9 mutant, putative ribosome biogenesis factors and CPN60 chaperonins. Protein interaction assays in yeast revealed that mTERF9 directly interact with these proteins. Our data demonstrate that mTERF9 integrates protein-protein and protein-RNA interactions to promote chloroplast ribosomal assembly and translation. Besides extending our knowledge of mTERF functional repertoire in plants, these findings provide an important insight into the chloroplast ribosome biogenesis.
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Affiliation(s)
- Louis-Valentin Méteignier
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg, France
| | - Rabea Ghandour
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Aude Zimmerman
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg, France
| | - Lauriane Kuhn
- Plateforme protéomique Strasbourg Esplanade FRC1589 du CNRS, Université de Strasbourg, 15 rue René Descartes, 67084 Strasbourg, France
| | - Jörg Meurer
- Plant Sciences, Faculty of Biology, Ludwig-Maximilians-University Munich, Großhaderner Street 2-4, 82152 Planegg-Martinsried, Germany
| | - Reimo Zoschke
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Kamel Hammani
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg, France
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Arabidopsis Mitochondrial Transcription Termination Factor mTERF2 Promotes Splicing of Group IIB Introns. Cells 2021; 10:cells10020315. [PMID: 33546419 PMCID: PMC7913559 DOI: 10.3390/cells10020315] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/29/2021] [Accepted: 01/30/2021] [Indexed: 12/21/2022] Open
Abstract
Plastid gene expression (PGE) is essential for chloroplast biogenesis and function and, hence, for plant development. However, many aspects of PGE remain obscure due to the complexity of the process. A hallmark of nuclear-organellar coordination of gene expression is the emergence of nucleus-encoded protein families, including nucleic-acid binding proteins, during the evolution of the green plant lineage. One of these is the mitochondrial transcription termination factor (mTERF) family, the members of which regulate various steps in gene expression in chloroplasts and/or mitochondria. Here, we describe the molecular function of the chloroplast-localized mTERF2 in Arabidopsis thaliana. The complete loss of mTERF2 function results in embryo lethality, whereas directed, microRNA (amiR)-mediated knockdown of MTERF2 is associated with perturbed plant development and reduced chlorophyll content. Moreover, photosynthesis is impaired in amiR-mterf2 plants, as indicated by reduced levels of photosystem subunits, although the levels of the corresponding messenger RNAs are not affected. RNA immunoprecipitation followed by RNA sequencing (RIP-Seq) experiments, combined with whole-genome RNA-Seq, RNA gel-blot, and quantitative RT-PCR analyses, revealed that mTERF2 is required for the splicing of the group IIB introns of ycf3 (intron 1) and rps12.
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Feiz L, Asakura Y, Mao L, Strickler SR, Fei Z, Rojas M, Barkan A, Stern DB. CFM1, a member of the CRM-domain protein family, functions in chloroplast group II intron splicing in Setaria viridis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:639-648. [PMID: 33140462 DOI: 10.1111/tpj.15060] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 08/27/2020] [Accepted: 10/19/2020] [Indexed: 06/11/2023]
Abstract
The chloroplast RNA splicing and ribosome maturation (CRM) domain is a RNA-binding domain found in a plant-specific protein family whose characterized members play essential roles in splicing group I and group II introns in mitochondria and chloroplasts. Together, these proteins are required for splicing of the majority of the approximately 20 chloroplast introns in land plants. Here, we provide evidence from Setaria viridis and maize that an uncharacterized member of this family, CRM Family Member1 (CFM1), promotes the splicing of most of the introns that had not previously been shown to require a CRM domain protein. A Setaria mutant expressing mutated CFM1 was strongly disrupted in the splicing of three chloroplast tRNAs: trnI, trnV and trnA. Analyses by RNA gel blot and polysome association suggest that the tRNA deficiencies lead to compromised chloroplast protein synthesis and the observed whole-plant chlorotic phenotypes. Co-immunoprecipitation data demonstrate that the maize CFM1 ortholog is bound to introns whose splicing is disrupted in the cfm1 mutant. With these results, CRM domain proteins have been shown to promote the splicing of all but two of the introns found in angiosperm chloroplast genomes.
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Affiliation(s)
- Leila Feiz
- Boyce Thompson Institute for Plant Research, Ithaca, NY, 14853, USA
| | - Yukari Asakura
- Institute of Molecular Biology, University of Oregon, Eugene, OR, 97403, USA
| | - Linyong Mao
- Boyce Thompson Institute for Plant Research, Ithaca, NY, 14853, USA
| | | | - Zhangjun Fei
- Boyce Thompson Institute for Plant Research, Ithaca, NY, 14853, USA
| | - Margarita Rojas
- Institute of Molecular Biology, University of Oregon, Eugene, OR, 97403, USA
| | - Alice Barkan
- Institute of Molecular Biology, University of Oregon, Eugene, OR, 97403, USA
| | - David B Stern
- Boyce Thompson Institute for Plant Research, Ithaca, NY, 14853, USA
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Westrich LD, Gotsmann VL, Herkt C, Ries F, Kazek T, Trösch R, Armbruster L, Mühlenbeck JS, Ramundo S, Nickelsen J, Finkemeier I, Wirtz M, Storchová Z, Räschle M, Willmund F. The versatile interactome of chloroplast ribosomes revealed by affinity purification mass spectrometry. Nucleic Acids Res 2021; 49:400-415. [PMID: 33330923 PMCID: PMC7797057 DOI: 10.1093/nar/gkaa1192] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 11/19/2020] [Accepted: 11/23/2020] [Indexed: 12/14/2022] Open
Abstract
In plant cells, chloroplast gene expression is predominantly controlled through post-transcriptional regulation. Such fine-tuning is vital for precisely orchestrating protein complex assembly as for the photosynthesis machinery and for quickly responding to environmental changes. While regulation of chloroplast protein synthesis is of central importance, little is known about the degree and nature of the regulatory network, mainly due to challenges associated with the specific isolation of transient ribosome interactors. Here, we established a ribosome affinity purification method, which enabled us to broadly uncover putative ribosome-associated proteins in chloroplasts. Endogenously tagging of a protein of the large or small subunit revealed not only interactors of the holo complex, but also preferential interactors of the two subunits. This includes known canonical regulatory proteins as well as several new proteins belonging to the categories of protein and RNA regulation, photosystem biogenesis, redox control and metabolism. The sensitivity of the here applied screen was validated for various transiently interacting proteins. We further provided evidence for the existence of a ribosome-associated Nα-acetyltransferase in chloroplasts and its ability to acetylate substrate proteins at their N-terminus. The broad set of ribosome interactors underscores the potential to regulate chloroplast gene expression on the level of protein synthesis.
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Affiliation(s)
- Lisa Désirée Westrich
- Molecular Genetics of Eukaryotes, University of Kaiserslautern, Paul-Ehrlich-Str. 23, 67663 Kaiserslautern, Germany
| | - Vincent Leon Gotsmann
- Molecular Genetics of Eukaryotes, University of Kaiserslautern, Paul-Ehrlich-Str. 23, 67663 Kaiserslautern, Germany
| | - Claudia Herkt
- Molecular Genetics of Eukaryotes, University of Kaiserslautern, Paul-Ehrlich-Str. 23, 67663 Kaiserslautern, Germany
| | - Fabian Ries
- Molecular Genetics of Eukaryotes, University of Kaiserslautern, Paul-Ehrlich-Str. 23, 67663 Kaiserslautern, Germany
| | - Tanja Kazek
- Molecular Genetics of Eukaryotes, University of Kaiserslautern, Paul-Ehrlich-Str. 23, 67663 Kaiserslautern, Germany
| | - Raphael Trösch
- Molecular Genetics of Eukaryotes, University of Kaiserslautern, Paul-Ehrlich-Str. 23, 67663 Kaiserslautern, Germany
| | - Laura Armbruster
- Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 360, 69120 Heidelberg, Germany
| | - Jens Stephan Mühlenbeck
- Plant Physiology, Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 7, 48149 Münster, Germany
| | - Silvia Ramundo
- Department of Biochemistry and Biophysics, University of California, 600 16th St, N316, San Francisco, CA 94143, USA
| | - Jörg Nickelsen
- Department of Molecular Plant Science, University of Munich, Grosshaderner-Str. 2-4, 82152 Planegg-Martinsried, Germany
| | - Iris Finkemeier
- Plant Physiology, Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 7, 48149 Münster, Germany
| | - Markus Wirtz
- Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 360, 69120 Heidelberg, Germany
| | - Zuzana Storchová
- Molecular Genetics, University of Kaiserslautern, Paul-Ehrlich-Str. 24, 67663 Kaiserslautern, Germany
| | - Markus Räschle
- Molecular Genetics, University of Kaiserslautern, Paul-Ehrlich-Str. 24, 67663 Kaiserslautern, Germany
| | - Felix Willmund
- Molecular Genetics of Eukaryotes, University of Kaiserslautern, Paul-Ehrlich-Str. 23, 67663 Kaiserslautern, Germany
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45
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Favier A, Gans P, Boeri Erba E, Signor L, Muthukumar SS, Pfannschmidt T, Blanvillain R, Cobessi D. The Plastid-Encoded RNA Polymerase-Associated Protein PAP9 Is a Superoxide Dismutase With Unusual Structural Features. FRONTIERS IN PLANT SCIENCE 2021; 12:668897. [PMID: 34276730 PMCID: PMC8278866 DOI: 10.3389/fpls.2021.668897] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 05/28/2021] [Indexed: 05/09/2023]
Abstract
In Angiosperms, the plastid-encoded RNA polymerase (PEP) is a multimeric enzyme, essential for the proper expression of the plastid genome during chloroplast biogenesis. It is especially required for the light initiated expression of photosynthesis genes and the subsequent build-up of the photosynthetic apparatus. The PEP complex is composed of a prokaryotic-type core of four plastid-encoded subunits and 12 nuclear-encoded PEP-associated proteins (PAPs). Among them, there are two iron superoxide dismutases, FSD2/PAP9 and FSD3/PAP4. Superoxide dismutases usually are soluble enzymes not bound into larger protein complexes. To investigate this unusual feature, we characterized PAP9 using molecular genetics, fluorescence microscopy, mass spectrometry, X-ray diffraction, and solution-state NMR. Despite the presence of a predicted nuclear localization signal within the sequence of the predicted chloroplast transit peptide, PAP9 was mainly observed within plastids. Mass spectrometry experiments with the recombinant Arabidopsis PAP9 suggested that monomers and dimers of PAP9 could be associated to the PEP complex. In crystals, PAP9 occurred as a dimeric enzyme that displayed a similar fold to that of the FeSODs or manganese SOD (MnSODs). A zinc ion, instead of the expected iron, was found to be penta-coordinated with a trigonal-bipyramidal geometry in the catalytic center of the recombinant protein. The metal coordination involves a water molecule and highly conserved residues in FeSODs. Solution-state NMR and DOSY experiments revealed an unfolded C-terminal 34 amino-acid stretch in the stand-alone protein and few internal residues interacting with the rest of the protein. We hypothesize that this C-terminal extension had appeared during evolution as a distinct feature of the FSD2/PAP9 targeting it to the PEP complex. Close vicinity to the transcriptional apparatus may allow for the protection against the strongly oxidizing aerial environment during plant conquering of terrestrial habitats.
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Affiliation(s)
- Adrien Favier
- Université Grenoble Alpes, CEA, CNRS, IBS, Grenoble, France
| | - Pierre Gans
- Université Grenoble Alpes, CEA, CNRS, IBS, Grenoble, France
| | | | - Luca Signor
- Université Grenoble Alpes, CEA, CNRS, IBS, Grenoble, France
| | | | | | - Robert Blanvillain
- Université Grenoble-Alpes, CNRS, CEA, INRA, IRIG-LPCV, Grenoble, France
- *Correspondence: Robert Blanvillain,
| | - David Cobessi
- Université Grenoble Alpes, CEA, CNRS, IBS, Grenoble, France
- David Cobessi,
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46
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Alamdari K, Fisher KE, Sinson AB, Chory J, Woodson JD. Roles for the chloroplast-localized pentatricopeptide repeat protein 30 and the 'mitochondrial' transcription termination factor 9 in chloroplast quality control. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 104:735-751. [PMID: 32779277 DOI: 10.1111/tpj.14963] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 07/20/2020] [Indexed: 05/11/2023]
Abstract
Chloroplasts constantly experience photo-oxidative stress while performing photosynthesis. This is particularly true under abiotic stresses that lead to the accumulation of reactive oxygen species (ROS) which oxidize DNA, proteins and lipids. Reactive oxygen species can also act as signals to induce acclimation through chloroplast degradation, cell death and nuclear gene expression. To better understand the mechanisms behind ROS signaling from chloroplasts, we have used the Arabidopsis thaliana mutant plastid ferrochelatase two (fc2) that conditionally accumulates the ROS singlet oxygen (1 O2 ) leading to chloroplast degradation and eventually cell death. Here we have mapped mutations that suppress chloroplast degradation in the fc2 mutant and demonstrate that they affect two independent loci (PPR30 and mTERF9) encoding chloroplast proteins predicted to be involved in post-transcriptional gene expression. These mutants exhibited broadly reduced chloroplast gene expression, impaired chloroplast development and reduced chloroplast stress signaling. Levels of 1 O2 , however, could be uncoupled from chloroplast degradation, suggesting that PPR30 and mTERF9 are involved in ROS signaling pathways. In the wild-type background, ppr30 and mTERF9 mutants were also observed to be less susceptible to cell death induced by excess light stress. While broad inhibition of plastid transcription with rifampicin was also able to suppress cell death in fc2 mutants, specific reductions in plastid gene expression using other mutations was not always sufficient. Together these results suggest that plastid gene expression, or the expression of specific plastid genes by PPR30 and mTERF0, is a necessary prerequisite for chloroplasts to activate the 1 O2 signaling pathways to induce chloroplast quality control pathways and/or cell death.
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Affiliation(s)
- Kamran Alamdari
- The School of Plant Sciences, University of Arizona, 1140 E. South Campus Drive, 303 Forbes Building, Tucson, AZ, 85721, USA
| | - Karen E Fisher
- The School of Plant Sciences, University of Arizona, 1140 E. South Campus Drive, 303 Forbes Building, Tucson, AZ, 85721, USA
| | - Andrew B Sinson
- The Division of Biological Sciences, The University of California San Diego, 9500 Gilman Dr., La Jolla, CA, 92093, USA
- Plant Biology Laboratory, The Salk Institute, 10010 N Torrey Pines Rd, La Jolla, CA, 92037, USA
| | - Joanne Chory
- Plant Biology Laboratory, The Salk Institute, 10010 N Torrey Pines Rd, La Jolla, CA, 92037, USA
- Howard Hughes Medical Institute, The Salk Institute, 10010 N Torrey Pines Rd, La Jolla, CA, 92037, USA
| | - Jesse D Woodson
- The School of Plant Sciences, University of Arizona, 1140 E. South Campus Drive, 303 Forbes Building, Tucson, AZ, 85721, USA
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47
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Huang W, Zhang Y, Shen L, Fang Q, Liu Q, Gong C, Zhang C, Zhou Y, Mao C, Zhu Y, Zhang J, Chen H, Zhang Y, Lin Y, Bock R, Zhou F. Accumulation of the RNA polymerase subunit RpoB depends on RNA editing by OsPPR16 and affects chloroplast development during early leaf development in rice. THE NEW PHYTOLOGIST 2020; 228:1401-1416. [PMID: 32583432 PMCID: PMC7689822 DOI: 10.1111/nph.16769] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 06/11/2020] [Indexed: 05/02/2023]
Abstract
Plastid-encoded genes are coordinately transcribed by the nucleus-encoded RNA polymerase (NEP) and the plastid-encoded RNA polymerase (PEP). Resulting primary transcripts are frequently subject to RNA editing by cytidine-to-uridine conversions at specific sites. The physiological role of many editing events is largely unknown. Here, we have used the CRISPR/Cas9 technique in rice to knock out a member of the PLS-DYW subfamily of pentatricopeptide repeat (PPR) proteins. We found that OsPPR16 is responsible for a single editing event at position 545 in the chloroplast rpoB messenger RNA (mRNA), resulting in an amino acid change from serine to leucine in the β-subunit of the PEP. In striking contrast to loss-of-function mutations of the putative orthologue in Arabidopsis, which were reported to have no visible phenotype, knockout of OsPPR16 leads to impaired accumulation of RpoB, reduced expression of PEP-dependent genes, and a pale phenotype during early plant development. Thus, by editing the rpoB mRNA, OsPPR16 is required for faithful plastid transcription, which in turn is required for Chl synthesis and efficient chloroplast development. Our results provide new insights into the interconnection of the finely tuned regulatory mechanisms that operate at the transcriptional and post-transcriptional levels of plastid gene expression.
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Affiliation(s)
- Weifeng Huang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhan430070China
| | - Yang Zhang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhan430070China
| | - Liqiang Shen
- Key Laboratory of Synthetic BiologyCAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
- University of Chinese Academy of SciencesBeijing100049China
| | - Qian Fang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhan430070China
| | - Qun Liu
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhan430070China
| | - Chenbo Gong
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhan430070China
| | - Chen Zhang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhan430070China
| | - Yong Zhou
- College of Bioscience and BioengineeringJiangxi Agricultural UniversityNanchan330045China
| | - Cui Mao
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhan430070China
| | - Yongli Zhu
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhan430070China
| | - Jinghong Zhang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhan430070China
| | - Hongping Chen
- Nanchang Subcenter of Rice National Engineering LaboratoryKey Laboratory of Rice Physiology and Genetics of Jiangxi ProvinceRice Research InstituteJiangxi Academy of Agricultural SciencesNanchang330200China
| | - Yu Zhang
- Key Laboratory of Synthetic BiologyCAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
| | - Yongjun Lin
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhan430070China
| | - Ralph Bock
- Max‐Planck‐Institut für Molekulare PflanzenphysiologieAm Mühlenberg 1Potsdam‐GolmD‐14476Germany
| | - Fei Zhou
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhan430070China
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48
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Tadini L, Jeran N, Peracchio C, Masiero S, Colombo M, Pesaresi P. The plastid transcription machinery and its coordination with the expression of nuclear genome: Plastid-Encoded Polymerase, Nuclear-Encoded Polymerase and the Genomes Uncoupled 1-mediated retrograde communication. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190399. [PMID: 32362266 DOI: 10.1098/rstb.2019.0399] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Plastid genes in higher plants are transcribed by at least two different RNA polymerases, the plastid-encoded RNA polymerase (PEP), a bacteria-like core enzyme whose subunits are encoded by plastid genes (rpoA, rpoB, rpoC1 and rpoC2), and the nuclear-encoded plastid RNA polymerase (NEP), a monomeric bacteriophage-type RNA polymerase. Both PEP and NEP enzymes are active in non-green plastids and in chloroplasts at all developmental stages. Their transcriptional activity is affected by endogenous and exogenous factors and requires a strict coordination within the plastid and with the nuclear gene expression machinery. This review focuses on the different molecular mechanisms underlying chloroplast transcription regulation and its coordination with the photosynthesis-associated nuclear genes (PhANGs) expression. Particular attention is given to the link between NEP and PEP activity and the GUN1- (Genomes Uncoupled 1) mediated chloroplast-to-nucleus retrograde communication with respect to the Δrpo adaptive response, i.e. the increased accumulation of NEP-dependent transcripts upon depletion of PEP activity, and the editing-level changes observed in NEP-dependent transcripts, including rpoB and rpoC1, in gun1 cotyledons after norflurazon or lincomycin treatment. The role of cytosolic preproteins and HSP90 chaperone as components of the GUN1-retrograde signalling pathway, when chloroplast biogenesis is inhibited in Arabidopsis cotyledons, is also discussed. This article is part of the theme issue 'Retrograde signalling from endosymbiotic organelles'.
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Affiliation(s)
- Luca Tadini
- Dipartimento di Bioscienze, Università degli studi di Milano, 20133 Milano, Italy
| | - Nicolaj Jeran
- Dipartimento di Bioscienze, Università degli studi di Milano, 20133 Milano, Italy
| | - Carlotta Peracchio
- Dipartimento di Bioscienze, Università degli studi di Milano, 20133 Milano, Italy
| | - Simona Masiero
- Dipartimento di Bioscienze, Università degli studi di Milano, 20133 Milano, Italy
| | - Monica Colombo
- Centro Ricerca e Innovazione, Fondazione Edmund Mach, 38010 San Michele all'Adige, Italy
| | - Paolo Pesaresi
- Dipartimento di Bioscienze, Università degli studi di Milano, 20133 Milano, Italy
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49
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Núñez-Delegido E, Robles P, Ferrández-Ayela A, Quesada V. Functional analysis of mTERF5 and mTERF9 contribution to salt tolerance, plastid gene expression and retrograde signalling in Arabidopsis thaliana. PLANT BIOLOGY (STUTTGART, GERMANY) 2020; 22:459-471. [PMID: 31850621 DOI: 10.1111/plb.13084] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 12/06/2019] [Indexed: 05/16/2023]
Abstract
We previously showed that Arabidopsis mda1 and mterf9 mutants, defective in the chloroplast-targeted mitochondrial transcription termination factors mTERF5 and mTERF9, respectively, display altered responses to abiotic stresses and abscisic acid (ABA), as well as perturbed development, likely through abnormal chloroplast biogenesis. To advance the functional analysis of mTERF5 and mTERF9, we obtained and characterized overexpression (OE) lines. Additionally, we studied genetic interactions between sca3-2, affected in the plastid-RNA polymerase RpoTp, and the mda1-1 and mterf9 mutations. We also investigated the role of mTERF5 and mTERF9 in plastid translation and plastid-to-nucleus signalling. We found that mTERF9 OE reduces salt and ABA tolerance, while mTERF5 or mTERF9 OE alter expression of nuclear and plastid genes. We determined that mda1-1 and mterf9 mutations genetically interact with sca3-2. Further, plastid 16S rRNA levels were reduced in mda1-1 and mterf9 mutants, and mterf9 was more sensitive to chemical inhibitors of chloroplast translation. Expression of the photosynthesis gene LHCB1, a retrograde signalling marker, was differentially affected in mda1-1 and/or mterf9 compared to wild-type Col-0, after treatments with inhibitors of carotenoid biosynthesis (norflurazon) or chloroplast translation (lincomycin). Moreover, mterf9, but not mda1-1, synergistically interacts with gun1-1, defective in GUN1, a central integrator of plastid retrograde signals. Our results show that mTERF9, and to a lesser extent mTERF5, are negative regulators of salt tolerance and that both genes are functionally related to RpoTp, and that mTERF9 is likely required for plastid ribosomal stability and/or assembly. Furthermore, our findings support a role for mTERF9 in retrograde signalling.
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Affiliation(s)
- E Núñez-Delegido
- Instituto de Bioingeniería, Universidad Miguel Hernández, Elche, Spain
| | - P Robles
- Instituto de Bioingeniería, Universidad Miguel Hernández, Elche, Spain
| | - A Ferrández-Ayela
- Instituto de Bioingeniería, Universidad Miguel Hernández, Elche, Spain
| | - V Quesada
- Instituto de Bioingeniería, Universidad Miguel Hernández, Elche, Spain
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50
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Teubner M, Lenzen B, Espenberger LB, Fuss J, Nickelsen J, Krause K, Ruwe H, Schmitz-Linneweber C. The Chloroplast Ribonucleoprotein CP33B Quantitatively Binds the psbA mRNA. PLANTS 2020; 9:plants9030367. [PMID: 32192026 PMCID: PMC7154868 DOI: 10.3390/plants9030367] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 03/09/2020] [Accepted: 03/11/2020] [Indexed: 01/25/2023]
Abstract
Chloroplast RNAs are stabilized and processed by a multitude of nuclear-encoded RNA-binding proteins, often in response to external stimuli like light and temperature. A particularly interesting RNA-based regulation occurs with the psbA mRNA, which shows light-dependent translation. Recently, the chloroplast ribonucleoprotein CP33B was identified as a ligand of the psbA mRNA. We here characterized the interaction of CP33B with chloroplast RNAs in greater detail using a combination of RIP-chip, quantitative dot-blot, and RNA-Bind-n-Seq experiments. We demonstrate that CP33B prefers psbA over all other chloroplast RNAs and associates with the vast majority of the psbA transcript pool. The RNA sequence target motif, determined in vitro, does not fully explain CP33B's preference for psbA, suggesting that there are other determinants of specificity in vivo.
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Affiliation(s)
- Marlene Teubner
- Institute of Biology, Department of Life Sciences, Humboldt University Berlin, 10115 Berlin, Germany; (M.T.); (B.L.); (L.B.E.); (H.R.)
| | - Benjamin Lenzen
- Institute of Biology, Department of Life Sciences, Humboldt University Berlin, 10115 Berlin, Germany; (M.T.); (B.L.); (L.B.E.); (H.R.)
| | - Lucas Bernal Espenberger
- Institute of Biology, Department of Life Sciences, Humboldt University Berlin, 10115 Berlin, Germany; (M.T.); (B.L.); (L.B.E.); (H.R.)
| | - Janina Fuss
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Framstredet 39, 9019 Tromsø, Norway; (J.F.); (K.K.)
| | - Jörg Nickelsen
- Department Biologie I, Botanik, Ludwig-Maximilians-Universität, 82152 Planegg-Martinsried, Germany;
| | - Kirsten Krause
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Framstredet 39, 9019 Tromsø, Norway; (J.F.); (K.K.)
| | - Hannes Ruwe
- Institute of Biology, Department of Life Sciences, Humboldt University Berlin, 10115 Berlin, Germany; (M.T.); (B.L.); (L.B.E.); (H.R.)
| | - Christian Schmitz-Linneweber
- Institute of Biology, Department of Life Sciences, Humboldt University Berlin, 10115 Berlin, Germany; (M.T.); (B.L.); (L.B.E.); (H.R.)
- Correspondence: ; Tel.: ++49-30-2093-49700
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