1
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Zhu L, Li X, Yang Z, Hao C, Li H, Qin X. The yellow-cotyledon gene (ATYCO) is a crucial factor for thylakoid formation and photosynthesis regulation in Arabidopsis. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2024; 348:112208. [PMID: 39089330 DOI: 10.1016/j.plantsci.2024.112208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 07/12/2024] [Accepted: 07/29/2024] [Indexed: 08/03/2024]
Abstract
Chloroplast development underpins plant growth, by facilitating not only photosynthesis but also other essential biochemical processes. Nonetheless, the regulatory mechanisms and functional components of chloroplast development remain largely uncharacterized due to their complexity. In our study, we identified a plastid-targeted gene, ATYCO/RP8/CDB1, as a critical factor in early chloroplast development in Arabidopsis thaliana. YCO knock-out mutant (yco) exhibited a seedling-lethal, albino phenotype, resulting from dysfunctional chloroplasts lacking thylakoid membranes. Conversely, YCO knock-down mutants produced a chlorophyll-deficient cotyledon and normal leaves when supplemented with sucrose. Transcription analysis also revealed that YCO deficiency could be partially compensated by sucrose supplementation, and that YCO played different roles in the cotyledons and the true leaves. In YCO knock-down mutants, the transcript levels of plastid-encoded RNA polymerase (PEP)-dependent genes and nuclear-encoded photosynthetic genes, as well as the accumulation of photosynthetic proteins, were significantly reduced in the cotyledons. Moreover, the chlorophyll-deficient phenotype in YCO knock-down line can be effectively suppressed by inhibition of PSI cyclic electron transport activity, implying an interaction between YCO and PSI cyclic electron transport. Taken together, our findings de underscore the vital role of YCO in early chloroplast development and photosynthesis.
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Affiliation(s)
- Lixia Zhu
- School of Biological Science and Technology, University of Jinan, Jinan 250022, China
| | - Xiuxiu Li
- School of Biological Science and Technology, University of Jinan, Jinan 250022, China; School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China
| | - Zonghui Yang
- Institute of Vegetables, Shandong Academy of Agricultural Sciences, Jinan 250100, China
| | - Chenyang Hao
- School of Biological Science and Technology, University of Jinan, Jinan 250022, China; School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China
| | - Hui Li
- School of Biological Science and Technology, University of Jinan, Jinan 250022, China
| | - Xiaochun Qin
- School of Biological Science and Technology, University of Jinan, Jinan 250022, China.
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2
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Wang Y, Wang D, Du J, Wang Y, Shao C, Cui C, Xiao J, Wang X. Crucial role of SWL1 in chloroplast biogenesis and development in Arabidopsis thaliana. PLANT CELL REPORTS 2024; 43:135. [PMID: 38704787 DOI: 10.1007/s00299-024-03210-1] [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: 02/03/2024] [Accepted: 04/01/2024] [Indexed: 05/07/2024]
Abstract
KEY MESSAGE The disruption of the SWL1 gene leads to a significant down regulation of chloroplast and secondary metabolites gene expression in Arabidopsis thaliana. And finally results in a dysfunction of chloroplast and plant growth. Although the development of the chloroplast has been a consistent focus of research, the corresponding regulatory mechanisms remain unidentified. In this study, the CRISPR/Cas9 system was used to mutate the SWL1 gene, resulting in albino cotyledons and variegated true leaf phenotype. Confocal microscopy and western blot of chloroplast protein fractions revealed that SWL1 localized in the chloroplast stroma. Electron microscopy indicated chloroplasts in the cotyledons of swl1 lack well-defined grana and internal membrane structures, and similar structures have been detected in the albino region of variegated true leaves. Transcriptome analysis revealed that down regulation of chloroplast and nuclear gene expression related to chloroplast, including light harvesting complexes, porphyrin, chlorophyll metabolism and carbon metabolism in the swl1 compared to wild-type plant. In addition, proteomic analysis combined with western blot analysis, showed that a significant decrease in chloroplast proteins of swl1. Furthermore, the expression of genes associated with secondary metabolites and growth hormones was also reduced, which may be attributed to SWL1 associated with absorption and fixation of inorganic carbon during chloroplast development. Together, the above findings provide valuable information to elucidate the exact function of SWL1 in chloroplast biogenesis and development.
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Affiliation(s)
- Yue Wang
- State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing, 100083, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China
| | - Dong Wang
- State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing, 100083, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China
| | - Jingxia Du
- State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing, 100083, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China
| | - Yan Wang
- College of Agriculture and Forestry, Hebei North University, Zhangjiakou, 075000, China
| | - Chunxue Shao
- State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing, 100083, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China
| | - Chuwen Cui
- State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing, 100083, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China
| | - Jianwei Xiao
- State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing, 100083, China.
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
| | - Xinwei Wang
- College of Agriculture and Forestry, Hebei North University, Zhangjiakou, 075000, China.
- SENO Biotechnology Co., Ltd., Zhangjiakou, 075000, China.
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3
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Xu M, Zhang X, Cao J, Liu J, He Y, Guan Q, Tian X, Tang J, Li X, Ren D, Bu Q, Wang Z. OsPGL3A encodes a DYW-type pentatricopeptide repeat protein involved in chloroplast RNA processing and regulated chloroplast development. MOLECULAR BREEDING : NEW STRATEGIES IN PLANT IMPROVEMENT 2024; 44:29. [PMID: 38549701 PMCID: PMC10965880 DOI: 10.1007/s11032-024-01468-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Accepted: 03/19/2024] [Indexed: 04/24/2024]
Abstract
The chloroplast serves as the primary site of photosynthesis, and its development plays a crucial role in regulating plant growth and morphogenesis. The Pentatricopeptide Repeat Sequence (PPR) proteins constitute a vast protein family that function in the post-transcriptional modification of RNA within plant organelles. In this study, we characterized mutant of rice with pale green leaves (pgl3a). The chlorophyll content of pgl3a at the seedling stage was significantly reduced compared to the wild type (WT). Transmission electron microscopy (TEM) and quantitative PCR analysis revealed that pgl3a exhibited aberrant chloroplast development compared to the wild type (WT), accompanied by significant alterations in gene expression levels associated with chloroplast development and photosynthesis. The Mutmap analysis revealed that a single base deletionin the coding region of Os03g0136700 in pgl3a. By employing CRISPR/Cas9 mediated gene editing, two homozygous cr-pgl3a mutants were generated and exhibited a similar phenotype to pgl3a, thereby confirming that Os03g0136700 was responsible for pgl3a. Consequently, it was designated as OsPGL3A. OsPGL3A belongs to the DYW-type PPR protein family and is localized in chloroplasts. Furthermore, we demonstrated that the RNA editing efficiency of rps8-182 and rpoC2-4106, and the splicing efficiency of ycf3-1 were significantly decreased in pgl3a mutants compared to WT. Collectively, these results indicate that OsPGL3A plays a crucial role in chloroplast development by regulating the editing and splicing of chloroplast genes in rice. Supplementary Information The online version contains supplementary material available at 10.1007/s11032-024-01468-7.
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Affiliation(s)
- Min Xu
- Key Laboratory of Soybean Molecular Design Breeding, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin, 150081 Heilongjiang China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Xinying Zhang
- College of Life Science, Northeast Agricultural University, Harbin, 150030 Heilongjiang China
| | - Jinzhe Cao
- Key Laboratory of the Ministry of Education for Ecological Restoration of Saline Vegetation, College of Life Sciences, Northeast Forestry University, Harbin, 150040 Heilongjiang China
| | - Jiali Liu
- Key Laboratory of the Ministry of Education for Ecological Restoration of Saline Vegetation, College of Life Sciences, Northeast Forestry University, Harbin, 150040 Heilongjiang China
| | - Yiyuan He
- Key Laboratory of Soybean Molecular Design Breeding, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin, 150081 Heilongjiang China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Qingjie Guan
- Key Laboratory of the Ministry of Education for Ecological Restoration of Saline Vegetation, College of Life Sciences, Northeast Forestry University, Harbin, 150040 Heilongjiang China
| | - Xiaojie Tian
- Key Laboratory of Soybean Molecular Design Breeding, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin, 150081 Heilongjiang China
| | - Jiaqi Tang
- Key Laboratory of Soybean Molecular Design Breeding, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin, 150081 Heilongjiang China
| | - Xiufeng Li
- Key Laboratory of Soybean Molecular Design Breeding, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin, 150081 Heilongjiang China
| | - Deyong Ren
- State Key Laboratory of Rice Biology and Breeding, China National Rice Research Institute, Hangzhou, 310006 People’s Republic of China
| | - Qingyun Bu
- Key Laboratory of Soybean Molecular Design Breeding, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin, 150081 Heilongjiang China
| | - Zhenyu Wang
- Key Laboratory of Soybean Molecular Design Breeding, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin, 150081 Heilongjiang China
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4
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do Prado PFV, Ahrens FM, Liebers M, Ditz N, Braun HP, Pfannschmidt T, Hillen HS. Structure of the multi-subunit chloroplast RNA polymerase. Mol Cell 2024; 84:910-925.e5. [PMID: 38428434 DOI: 10.1016/j.molcel.2024.02.003] [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] [Received: 09/25/2023] [Revised: 01/26/2024] [Accepted: 02/06/2024] [Indexed: 03/03/2024]
Abstract
Chloroplasts contain a dedicated genome that encodes subunits of the photosynthesis machinery. Transcription of photosynthesis genes is predominantly carried out by a plastid-encoded RNA polymerase (PEP), a nearly 1 MDa complex composed of core subunits with homology to eubacterial RNA polymerases (RNAPs) and at least 12 additional chloroplast-specific PEP-associated proteins (PAPs). However, the architecture of this complex and the functions of the PAPs remain unknown. Here, we report the cryo-EM structure of a 19-subunit PEP complex from Sinapis alba (white mustard). The structure reveals that the PEP core resembles prokaryotic and nuclear RNAPs but contains chloroplast-specific features that mediate interactions with the PAPs. The PAPs are unrelated to known transcription factors and arrange around the core in a unique fashion. Their structures suggest potential functions during transcription in the chemical environment of chloroplasts. These results reveal structural insights into chloroplast transcription and provide a framework for understanding photosynthesis gene expression.
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Affiliation(s)
- Paula F V do Prado
- University Medical Center Göttingen, Department of Cellular Biochemistry, Humboldtallee 23, 37073 Göttingen, Germany; Max Planck Institute for Multidisciplinary Sciences, Research Group Structure and Function of Molecular Machines, Am Fassberg 11, 37077 Göttingen, Germany; Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, 37075 Göttingen, Germany
| | - Frederik M Ahrens
- Institute of Botany, Plant Physiology, Leibniz University Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany
| | - Monique Liebers
- Institute of Botany, Plant Physiology, Leibniz University Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany
| | - Noah Ditz
- Institute of Plant Genetics, Plant Molecular Biology and Plant Proteomics, Leibniz University Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany
| | - Hans-Peter Braun
- Institute of Plant Genetics, Plant Molecular Biology and Plant Proteomics, Leibniz University Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany
| | - Thomas Pfannschmidt
- Institute of Botany, Plant Physiology, Leibniz University Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany.
| | - Hauke S Hillen
- University Medical Center Göttingen, Department of Cellular Biochemistry, Humboldtallee 23, 37073 Göttingen, Germany; Max Planck Institute for Multidisciplinary Sciences, Research Group Structure and Function of Molecular Machines, Am Fassberg 11, 37077 Göttingen, Germany; Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, 37075 Göttingen, Germany; Göttingen Center for Molecular Biosciences (GZMB), Research Group Structure and Function of Molecular Machines, University of Göttingen, 37077 Göttingen, Germany.
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5
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Vergara-Cruces Á, Pramanick I, Pearce D, Vogirala VK, Byrne MJ, Low JKK, Webster MW. Structure of the plant plastid-encoded RNA polymerase. Cell 2024; 187:1145-1159.e21. [PMID: 38428394 DOI: 10.1016/j.cell.2024.01.036] [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] [Received: 10/10/2023] [Revised: 12/18/2023] [Accepted: 01/24/2024] [Indexed: 03/03/2024]
Abstract
Chloroplast genes encoding photosynthesis-associated proteins are predominantly transcribed by the plastid-encoded RNA polymerase (PEP). PEP is a multi-subunit complex composed of plastid-encoded subunits similar to bacterial RNA polymerases (RNAPs) stably bound to a set of nuclear-encoded PEP-associated proteins (PAPs). PAPs are essential to PEP activity and chloroplast biogenesis, but their roles are poorly defined. Here, we present cryoelectron microscopy (cryo-EM) structures of native 21-subunit PEP and a PEP transcription elongation complex from white mustard (Sinapis alba). We identify that PAPs encase the core polymerase, forming extensive interactions that likely promote complex assembly and stability. During elongation, PAPs interact with DNA downstream of the transcription bubble and with the nascent mRNA. The models reveal details of the superoxide dismutase, lysine methyltransferase, thioredoxin, and amino acid ligase enzymes that are subunits of PEP. Collectively, these data provide a foundation for the mechanistic understanding of chloroplast transcription and its role in plant growth and adaptation.
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Affiliation(s)
- Ángel Vergara-Cruces
- Department of Biochemistry and Metabolism, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
| | - Ishika Pramanick
- Department of Biochemistry and Metabolism, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
| | - David Pearce
- Department of Biochemistry and Metabolism, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK; School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Vinod K Vogirala
- Electron Bio-Imaging Centre (eBIC), Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
| | - Matthew J Byrne
- Electron Bio-Imaging Centre (eBIC), Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
| | - Jason K K Low
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2050, Australia
| | - Michael W Webster
- Department of Biochemistry and Metabolism, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK.
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6
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Wu XX, Mu WH, Li F, Sun SY, Cui CJ, Kim C, Zhou F, Zhang Y. Cryo-EM structures of the plant plastid-encoded RNA polymerase. Cell 2024; 187:1127-1144.e21. [PMID: 38428393 DOI: 10.1016/j.cell.2024.01.026] [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] [Received: 10/10/2023] [Revised: 12/12/2023] [Accepted: 01/16/2024] [Indexed: 03/03/2024]
Abstract
Chloroplasts are green plastids in the cytoplasm of eukaryotic algae and plants responsible for photosynthesis. The plastid-encoded RNA polymerase (PEP) plays an essential role during chloroplast biogenesis from proplastids and functions as the predominant RNA polymerase in mature chloroplasts. The PEP-centered transcription apparatus comprises a bacterial-origin PEP core and more than a dozen eukaryotic-origin PEP-associated proteins (PAPs) encoded in the nucleus. Here, we determined the cryo-EM structures of Nicotiana tabacum (tobacco) PEP-PAP apoenzyme and PEP-PAP transcription elongation complexes at near-atomic resolutions. Our data show the PEP core adopts a typical fold as bacterial RNAP. Fifteen PAPs bind at the periphery of the PEP core, facilitate assembling the PEP-PAP supercomplex, protect the complex from oxidation damage, and likely couple gene transcription with RNA processing. Our results report the high-resolution architecture of the chloroplast transcription apparatus and provide the structural basis for the mechanistic and functional study of transcription regulation in chloroplasts.
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Affiliation(s)
- Xiao-Xian Wu
- Key Laboratory of Synthetic Biology, Key Laboratory of Plant Design, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Wen-Hui Mu
- Key Laboratory of Synthetic Biology, Key Laboratory of Plant Design, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng 475004, China
| | - Fan Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Shu-Yi Sun
- Key Laboratory of Synthetic Biology, Key Laboratory of Plant Design, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chao-Jun Cui
- University of Chinese Academy of Sciences, Beijing 100049, China; Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Chanhong Kim
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Fei Zhou
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China.
| | - Yu Zhang
- Key Laboratory of Synthetic Biology, Key Laboratory of Plant Design, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.
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7
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Loiacono FV, Bock R. An RNA polymerase that became a Swiss army knife. Cell 2024; 187:1106-1108. [PMID: 38428392 DOI: 10.1016/j.cell.2024.01.044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 01/24/2024] [Accepted: 01/26/2024] [Indexed: 03/03/2024]
Abstract
RNA polymerases (RNAPs) control the first step of gene expression in all forms of life by transferring genetic information from DNA to RNA, a process known as transcription. In this issue of Cell, Webster et al. and Wu et al. report three-dimensional structures of RNAP complexes from chloroplasts.
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Affiliation(s)
- F Vanessa Loiacono
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Ralph Bock
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany.
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8
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Mahapatra K, Mukherjee A, Suyal S, Dar MA, Bhagavatula L, Datta S. Regulation of chloroplast biogenesis, development, and signaling by endogenous and exogenous cues. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2024; 30:167-183. [PMID: 38623168 PMCID: PMC11016055 DOI: 10.1007/s12298-024-01427-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 02/07/2024] [Accepted: 02/27/2024] [Indexed: 04/17/2024]
Abstract
Chloroplasts are one of the defining features in most plants, primarily known for their unique property to carry out photosynthesis. Besides this, chloroplasts are also associated with hormone and metabolite productions. For this, biogenesis and development of chloroplast are required to be synchronized with the seedling growth to corroborate the maximum rate of photosynthesis following the emergence of seedlings. Chloroplast biogenesis and development are dependent on the signaling to and from the chloroplast, which are in turn regulated by several endogenous and exogenous cues. Light and hormones play a crucial role in chloroplast maturation and development. Chloroplast signaling involves a coordinated two-way connection between the chloroplast and nucleus, termed retrograde and anterograde signaling, respectively. Anterograde and retrograde signaling are involved in regulation at the transcriptional level and downstream modifications and are modulated by several metabolic and external cues. The communication between chloroplast and nucleus is essential for plants to develop strategies to cope with various stresses including high light or high heat. In this review, we have summarized several aspects of chloroplast development and its regulation through the interplay of various external and internal factors. We have also discussed the involvement of chloroplasts as sensors of various external environment stress factors including high light and temperature, and communicate via a series of retrograde signals to the nucleus, thus playing an essential role in plants' abiotic stress response.
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Affiliation(s)
- Kalyan Mahapatra
- Plant Cell and Developmental Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh 462066 India
| | - Arpan Mukherjee
- Plant Cell and Developmental Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh 462066 India
| | - Shikha Suyal
- Plant Cell and Developmental Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh 462066 India
| | - Mansoor Ali Dar
- Plant Cell and Developmental Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh 462066 India
| | | | - Sourav Datta
- Plant Cell and Developmental Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh 462066 India
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9
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Seo DH, Jang J, Park D, Yoon Y, Choi YD, Jang G. PEP-ASSOCIATED PROTEIN 3 regulates rice tiller formation and grain yield by controlling chloroplast biogenesis. PLANT PHYSIOLOGY 2024; 194:805-818. [PMID: 37819034 PMCID: PMC10828210 DOI: 10.1093/plphys/kiad536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 08/15/2023] [Accepted: 09/14/2023] [Indexed: 10/13/2023]
Abstract
Plastid-encoded RNA polymerase (PEP) plays a pivotal role in chloroplast development by governing the transcription of chloroplast genes, and PEP-associated proteins (PAPs) modulate PEP transcriptional activity. Therefore, PAPs provide an intriguing target for those efforts to improve yield, by enhancing chloroplast development. In this study, we identified the rice (Oryza sativa) OsPAP3 gene and characterized its function in chloroplast development. OsPAP3 expression was light-dependent and leaf-specific, similar to the PEP-dependent chloroplast gene RUBISCO LARGE SUBUNIT (OsRbcL), and OsPAP3 protein localized to chloroplast nucleoids where PEP functions. Analysis of loss-of-function and gain-of-function mutants showed that the expression of OsPAP3 is tightly linked to chloroplast gene expression and chloroplast biogenesis in rice. Homozygous knockout mutants of OsPAP3 had fewer chloroplasts than wild type, whereas plants overexpressing OsPAP3 had more chloroplasts. Also, OsPAP3 knockout suppressed the PEP-dependent expression of chloroplast genes, but OsPAP3 overexpression increased their expression. These findings indicate that OsPAP3 regulates chloroplast biogenesis in rice by controlling the PEP-dependent expression of chloroplast genes. More importantly, data from 3 seasons of field cultivation revealed that the overexpression of OsPAP3 improves rice grain yield by approximately 25%, largely due to increased tiller formation. Collectively, these observations suggest that OsPAP3 regulates rice growth and productivity by promoting chloroplast development.
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Affiliation(s)
- Deok Hyun Seo
- School of Biological Sciences and Technology, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jinwoo Jang
- School of Biological Sciences and Technology, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Dongryeol Park
- School of Biological Sciences and Technology, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Youngdae Yoon
- Department of Environmental Health Science, Konkuk University, Seoul 05029, Republic of Korea
| | - Yang Do Choi
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Geupil Jang
- School of Biological Sciences and Technology, Chonnam National University, Gwangju 61186, Republic of Korea
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10
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Tiwari LD, Bdolach E, Prusty MR, Bodenheimer S, Be'ery A, Faigenboim-Doron A, Yamamoto E, Panzarová K, Kashkush K, Shental N, Fridman E. Cytonuclear interactions modulate the plasticity of photosynthetic rhythmicity and growth in wild barley. PHYSIOLOGIA PLANTARUM 2024; 176:e14192. [PMID: 38351880 DOI: 10.1111/ppl.14192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 01/22/2024] [Indexed: 02/16/2024]
Abstract
In plants, the contribution of the plasmotype (mitochondria and chloroplast) in controlling the circadian clock plasticity and possible consequences on cytonuclear genetic makeup have yet to be fully elucidated. A genome-wide association study in the wild barley (Hordeum vulgare ssp. spontaneum) B1K collection identified overlap with our previously mapped DRIVERS OF CLOCKS (DOCs) loci in wild-cultivated interspecific population. Moreover, we identified non-random segregation and epistatic interactions between nuclear DOCs loci and the chloroplastic RpoC1 gene, indicating an adaptive value for specific cytonuclear gene combinations. Furthermore, we show that DOC1.1, which harbours the candidate SIGMA FACTOR-B (SIG-B) gene, is linked with the differential expression of SIG-B and CCA1 genes and contributes to the circadian gating response to heat. High-resolution temporal growth and photosynthesis measurements of B1K also link the DOCs loci to differential growth, Chl content and quantum yield. To validate the involvement of the Plastid encoded polymerase (PEP) complex, we over-expressed the two barley chloroplastic RpoC1 alleles in Arabidopsis and identified significant differential plasticity under elevated temperatures. Finally, enhanced clock plasticity of de novo ENU (N-Ethyl-N-nitrosourea) -induced barley rpoB1 mutant further implicates the PEP complex as a key player in regulating the circadian clock output. Overall, this study highlights the contribution of specific cytonuclear interaction between rpoC1 (PEP gene) and SIG-B with distinct circadian timing regulation under heat, and their pleiotropic effects on growth implicate an adaptive value.
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Affiliation(s)
- Lalit Dev Tiwari
- Plant Sciences Institute, Volcani Agricultural Research Organization (ARO), Bet Dagan, Israel
| | - Eyal Bdolach
- Plant Sciences Institute, Volcani Agricultural Research Organization (ARO), Bet Dagan, Israel
- Department of Life Sciences, Ben-Gurion University, Beer-Sheva, Israel
| | - Manas Ranjan Prusty
- Plant Sciences Institute, Volcani Agricultural Research Organization (ARO), Bet Dagan, Israel
| | - Schewach Bodenheimer
- Plant Sciences Institute, Volcani Agricultural Research Organization (ARO), Bet Dagan, Israel
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Avital Be'ery
- Plant Sciences Institute, Volcani Agricultural Research Organization (ARO), Bet Dagan, Israel
| | - Adi Faigenboim-Doron
- Plant Sciences Institute, Volcani Agricultural Research Organization (ARO), Bet Dagan, Israel
| | - Eiji Yamamoto
- Graduate School of Agriculture, Meiji University, Kawasaki, Kanagawa, Japan
| | | | - Khalil Kashkush
- Department of Life Sciences, Ben-Gurion University, Beer-Sheva, Israel
| | - Noam Shental
- Department of Mathematics and Computer Science, The Open University of Israel, Raanana, Israel
| | - Eyal Fridman
- Plant Sciences Institute, Volcani Agricultural Research Organization (ARO), Bet Dagan, Israel
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11
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Wang X, Qi Y, Liu N, Zhang Q, Xie S, Lei Y, Li B, Shao J, Yu F, Liu X. Interaction of PALE CRESS with PAP2/pTAC2 and PAP3/pTAC10 affects the accumulation of plastid-encoded RNA polymerase complexes in Arabidopsis. THE NEW PHYTOLOGIST 2023; 240:1433-1448. [PMID: 37668229 DOI: 10.1111/nph.19243] [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: 05/10/2023] [Accepted: 08/09/2023] [Indexed: 09/06/2023]
Abstract
The transcription of photosynthesis genes in chloroplasts is largely mediated by the plastid-encoded RNA polymerase (PEP), which resembles prokaryotic-type RNA polymerases, but with plant-specific accessory subunits known as plastid transcriptionally active chromosome proteins (pTACs) or PEP-associated proteins (PAPs). However, whether additional factors are involved in the biogenesis of PEP complexes remains unknown. Here, we investigated the function of an essential gene, PALE CRESS (PAC), in the accumulation of PEP complexes in chloroplasts. We established that an Arabidopsis leaf variegation mutant, variegated 6-1 (var6-1), is a hypomorphic allele of PAC. Unexpectedly, we revealed that a fraction of VAR6/PAC is associated with thylakoid membranes, where it interacts with PEP complexes. The accumulation of PEP complexes is defective in both var6-1 and the null allele var6-2. Further protein interaction assays confirmed that VAR6/PAC interacts directly with the PAP2/pTAC2 and PAP3/pTAC10 subunits of PEP complexes. Moreover, we generated viable hypomorphic alleles of the essential gene PAP2/pTAC2, and revealed a genetic interaction between PAC and PAP2/pTAC2 in photosynthesis gene expression and PEP complex accumulation. Our findings establish that VAR6/PAC affects PEP complex accumulation through interactions with PAP2/pTAC2 and PAP3/pTAC10, and provide new insights into the accumulation of PEP and chloroplast development.
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Affiliation(s)
- Xiaomin Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yafei Qi
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Na Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Qiaoxin Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Sha Xie
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yang Lei
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Bilang Li
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Jingxia Shao
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Fei Yu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Institute of Future Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xiayan Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
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12
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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: 8] [Impact Index Per Article: 8.0] [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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13
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Lan J, Lin Q, Zhou C, Liu X, Miao R, Ma T, Chen Y, Mou C, Jing R, Feng M, Nguyen T, Ren Y, Cheng Z, Zhang X, Liu S, Jiang L, Wan J. Young Leaf White Stripe encodes a P-type PPR protein required for chloroplast development. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023. [PMID: 36897026 DOI: 10.1111/jipb.13477] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Accepted: 03/07/2023] [Indexed: 05/09/2023]
Abstract
Pentatricopeptide repeat (PPR) proteins function in post-transcriptional regulation of organellar gene expression. Although several PPR proteins are known to function in chloroplast development in rice (Oryza sativa), the detailed molecular functions of many PPR proteins remain unclear. Here, we characterized a rice young leaf white stripe (ylws) mutant, which has defective chloroplast development during early seedling growth. Map-based cloning revealed that YLWS encodes a novel P-type chloroplast-targeted PPR protein with 11 PPR motifs. Further expression analyses showed that many nuclear- and plastid-encoded genes in the ylws mutant were significantly changed at the RNA and protein levels. The ylws mutant was impaired in chloroplast ribosome biogenesis and chloroplast development under low-temperature conditions. The ylws mutation causes defects in the splicing of atpF, ndhA, rpl2, and rps12, and editing of ndhA, ndhB, and rps14 transcripts. YLWS directly binds to specific sites in the atpF, ndhA, and rpl2 pre-mRNAs. Our results suggest that YLWS participates in chloroplast RNA group II intron splicing and plays an important role in chloroplast development during early leaf development.
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Affiliation(s)
- Jie Lan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Qibing Lin
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Chunlei Zhou
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xi Liu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Rong Miao
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Tengfei Ma
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yaping Chen
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Changling Mou
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Ruonan Jing
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Miao Feng
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Thanhliem Nguyen
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yulong Ren
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zhijun Cheng
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xin Zhang
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Shijia Liu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Ling Jiang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jianmin Wan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
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14
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Mehrez M, Romand S, Field B. New perspectives on the molecular mechanisms of stress signalling by the nucleotide guanosine tetraphosphate (ppGpp), an emerging regulator of photosynthesis in plants and algae. THE NEW PHYTOLOGIST 2023; 237:1086-1099. [PMID: 36349398 PMCID: PMC10107265 DOI: 10.1111/nph.18604] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 10/13/2022] [Indexed: 06/16/2023]
Abstract
The nucleotides guanosine tetraphosphate and guanosine pentaphosphate (together (p)ppGpp) are found in a wide range of prokaryotic and eukaryotic organisms where they are associated with stress signalling. In this review, we will discuss recent research highlighting the role of (p)ppGpp signalling as a conserved regulator of photosynthetic activity in the chloroplasts of plants and algae, and the latest discoveries that open up new perspectives on the emerging roles of (p)ppGpp in acclimation to environmental stress. We explore how rapid advances in the study of (p)ppGpp signalling in prokaryotes are now revealing large gaps in our understanding of the molecular mechanisms of signalling by (p)ppGpp and related nucleotides in plants and algae. Filling in these gaps is likely to lead to the discovery of conserved as well as new plant- and algal-specific (p)ppGpp signalling mechanisms that will offer new insights into the taming of the chloroplast and the regulation of stress tolerance.
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Affiliation(s)
- Marwa Mehrez
- Aix‐Marseille University, CEA, CNRS, BIAM, UMR726513009MarseilleFrance
- Faculty of Sciences of Tunis, Laboratory of Molecular Genetics, Immunology and BiotechnologyUniversity of Tunis El Manar2092TunisTunisia
| | - Shanna Romand
- Aix‐Marseille University, CEA, CNRS, BIAM, UMR726513009MarseilleFrance
| | - Ben Field
- Aix‐Marseille University, CEA, CNRS, BIAM, UMR726513009MarseilleFrance
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15
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Anterograde signaling controls plastid transcription via sigma factors separately from nuclear photosynthesis genes. Nat Commun 2022; 13:7440. [PMID: 36460634 PMCID: PMC9718756 DOI: 10.1038/s41467-022-35080-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 11/16/2022] [Indexed: 12/03/2022] Open
Abstract
Light initiates chloroplast biogenesis in Arabidopsis by eliminating PHYTOCHROME-INTERACTING transcription FACTORs (PIFs), which in turn de-represses nuclear photosynthesis genes, and synchronously, generates a nucleus-to-plastid (anterograde) signal that activates the plastid-encoded bacterial-type RNA polymerase (PEP) to transcribe plastid photosynthesis genes. However, the identity of the anterograde signal remains frustratingly elusive. The main challenge has been the difficulty to distinguish regulators from the plethora of necessary components for plastid transcription and other essential chloroplast functions, such as photosynthesis. Here, we show that the genome-wide induction of nuclear photosynthesis genes is insufficient to activate the PEP. PEP inhibition is imposed redundantly by multiple PIFs and requires PIF3's activator activity. Among the nuclear-encoded components of the PEP holoenzyme, we identify four light-inducible, PIF-repressed sigma factors as anterograde signals. Together, our results elucidate that light-dependent inhibition of PIFs activates plastid photosynthesis genes via sigma factors as anterograde signals in parallel with the induction of nuclear photosynthesis genes.
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16
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Liebers M, Cozzi C, Uecker F, Chambon L, Blanvillain R, Pfannschmidt T. Biogenic signals from plastids and their role in chloroplast development. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:7105-7125. [PMID: 36002302 DOI: 10.1093/jxb/erac344] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 08/23/2022] [Indexed: 06/15/2023]
Abstract
Plant seeds do not contain differentiated chloroplasts. Upon germination, the seedlings thus need to gain photoautotrophy before storage energies are depleted. This requires the coordinated expression of photosynthesis genes encoded in nuclear and plastid genomes. Chloroplast biogenesis needs to be additionally coordinated with the light regulation network that controls seedling development. This coordination is achieved by nucleus to plastid signals called anterograde and plastid to nucleus signals termed retrograde. Retrograde signals sent from plastids during initial chloroplast biogenesis are also called biogenic signals. They have been recognized as highly important for proper chloroplast biogenesis and for seedling development. The molecular nature, transport, targets, and signalling function of biogenic signals are, however, under debate. Several studies disproved the involvement of a number of key components that were at the base of initial models of retrograde signalling. New models now propose major roles for a functional feedback between plastid and cytosolic protein homeostasis in signalling plastid dysfunction as well as the action of dually localized nucleo-plastidic proteins that coordinate chloroplast biogenesis with light-dependent control of seedling development. This review provides a survey of the developments in this research field, summarizes the unsolved questions, highlights several recent advances, and discusses potential new working modes.
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Affiliation(s)
- Monique Liebers
- Gottfried-Wilhelm-Leibniz-Universität Hannover, Naturwissenschaftliche Fakultät, Institut für Botanik, Pflanzenphysiologie, Herrenhäuser Str. 2, D-30419 Hannover, Germany
| | - Carolina Cozzi
- Gottfried-Wilhelm-Leibniz-Universität Hannover, Naturwissenschaftliche Fakultät, Institut für Botanik, Pflanzenphysiologie, Herrenhäuser Str. 2, D-30419 Hannover, Germany
| | - Finia Uecker
- Gottfried-Wilhelm-Leibniz-Universität Hannover, Naturwissenschaftliche Fakultät, Institut für Botanik, Pflanzenphysiologie, Herrenhäuser Str. 2, D-30419 Hannover, Germany
| | - Louise Chambon
- Université Grenoble-Alpes, CNRS, CEA, INRA, IRIG-LPCV, F-38000 Grenoble, France
| | - Robert Blanvillain
- Université Grenoble-Alpes, CNRS, CEA, INRA, IRIG-LPCV, F-38000 Grenoble, France
| | - Thomas Pfannschmidt
- Gottfried-Wilhelm-Leibniz-Universität Hannover, Naturwissenschaftliche Fakultät, Institut für Botanik, Pflanzenphysiologie, Herrenhäuser Str. 2, D-30419 Hannover, Germany
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17
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Park HS, Jeon JH, Cho W, Lee Y, Park JY, Kim J, Park YS, Koo HJ, Kang JH, Lee TJ, Kim SH, Kim JB, Kwon HY, Kim SH, Paek NC, Jang G, Suh JY, Yang TJ. High-throughput discovery of plastid genes causing albino phenotypes in ornamental chimeric plants. HORTICULTURE RESEARCH 2022; 10:uhac246. [PMID: 36643742 PMCID: PMC9832966 DOI: 10.1093/hr/uhac246] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 10/26/2022] [Indexed: 06/17/2023]
Abstract
Chimeric plants composed of green and albino tissues have great ornamental value. To unveil the functional genes responsible for albino phenotypes in chimeric plants, we inspected the complete plastid genomes (plastomes) in green and albino leaf tissues from 23 ornamental chimeric plants belonging to 20 species, including monocots, dicots, and gymnosperms. In nine chimeric plants, plastomes were identical between green and albino tissues. Meanwhile, another 14 chimeric plants were heteroplasmic, showing a mutation between green and albino tissues. We identified 14 different point mutations in eight functional plastid genes related to plastid-encoded RNA polymerase (rpo) or photosystems which caused albinism in the chimeric plants. Among them, 12 were deleterious mutations in the target genes, in which early termination appeared due to small deletion-mediated frameshift or single nucleotide substitution. Another was single nucleotide substitution in an intron of the ycf3 and the other was a missense mutation in coding region of the rpoC2 gene. We inspected chlorophyll structure, protein functional model of the rpoC2, and expression levels of the related genes in green and albino tissues of Reynoutria japonica. A single amino acid change, histidine-to-proline substitution, in the rpoC2 protein may destabilize the peripheral helix of plastid-encoded RNA polymerase, impairing the biosynthesis of the photosynthesis system in the albino tissue of R. japonica chimera plant.
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Affiliation(s)
| | | | | | | | - Jee Young Park
- Department of Agriculture, Forestry and Bioresources, Research Institute of Agriculture and Life Sciences, and Plant Genomics and Breeding Institute, College of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jiseok Kim
- Department of Agriculture, Forestry and Bioresources, Research Institute of Agriculture and Life Sciences, and Plant Genomics and Breeding Institute, College of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Young Sang Park
- Department of Agriculture, Forestry and Bioresources, Research Institute of Agriculture and Life Sciences, and Plant Genomics and Breeding Institute, College of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Hyun Jo Koo
- Department of Agriculture, Forestry and Bioresources, Research Institute of Agriculture and Life Sciences, and Plant Genomics and Breeding Institute, College of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jung Hwa Kang
- Hantaek Botanical Garden, Yongin, Gyeonggi-do, 17183, Republic of Korea
| | - Taek Joo Lee
- Hantaek Botanical Garden, Yongin, Gyeonggi-do, 17183, Republic of Korea
| | - Sang Hoon Kim
- Radiation Breeding Research Team, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 56212, Korea
| | - Jin-Baek Kim
- Radiation Breeding Research Team, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 56212, Korea
| | - Hae-Yun Kwon
- Special Forest Resources Division, National Institute of Forest Science, Suwon 16631, Korea
| | - Suk-Hwan Kim
- Department of Agriculture, Forestry and Bioresources, Research Institute of Agriculture and Life Sciences, and Plant Genomics and Breeding Institute, College of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Nam-Chon Paek
- Department of Agriculture, Forestry and Bioresources, Research Institute of Agriculture and Life Sciences, and Plant Genomics and Breeding Institute, College of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Geupil Jang
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, South Korea
| | - Jeong-Yong Suh
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
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18
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Wang Y, Yang Z, Zhang M, Ai P. A chloroplast-localized pentatricopeptide repeat protein involved in RNA editing and splicing and its effects on chloroplast development in rice. BMC PLANT BIOLOGY 2022; 22:437. [PMID: 36096762 PMCID: PMC9469629 DOI: 10.1186/s12870-022-03819-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Accepted: 08/24/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND The chloroplast is the organelle responsible for photosynthesis in higher plants. The generation of functional chloroplasts depends on the precise coordination of gene expression in the nucleus and chloroplasts and is essential for the development of plants. However, little is known about nuclear-plastid regulatory mechanisms at the early stage of chloroplast generation in rice. RESULTS In this study, we identified a rice (Oryza sativa) mutant that exhibited albino and seedling-lethal phenotypes and named it ssa1(seedling stage albino1). Transmission electron microscopy (TEM) analysis indicated that the chloroplasts of ssa1 did not have organized thylakoid lamellae and that the chloroplast structure was destroyed. Genetic analysis revealed that the albino phenotypes of ssa1 were controlled by a pair of recessive nuclear genes. Map-based cloning experiments found that SSA1 encoded a pentapeptide repeat (PPR) protein that was allelic to OSOTP51,which was previously reported to participate in Photosystem I (PSI) assembly. The albino phenotype was reversed to the wild type (WT) phenotype when the normal SSA1 sequence was expressed in ssa1 under the drive of the actin promoter. Knockout experiments further created mutants ssa1-2/1-9, which had a phenotype similar to that of ssa1. SSA1 consisted of 7 pentatricopeptide repeat domains and two C-terminal LAGLIDADG tandem sequence motifs and was located in the chloroplast. GUS staining and qRT-PCR analysis showed that SSA1 was mainly expressed in young leaves and stems. In the ssa1 mutants, plastid genes transcribed by plastid-encoded RNA polymerase decreased, while those transcribed by nuclear-encoded RNA polymerase increased at the mRNA level. Loss-of-function SSA1 destroys RNA editing of ndhB-737 and intron splicing of atpF and ycf3-2 in the plastid genome. Yeast two-hybrid and BiFC assays revealed that SSA1 physically interacted with two new RNA editing partners, OsMORF8 and OsTRXz, which have potential functions in RNA editing and chloroplast biogenesis. CONCLUSIONS Rice SSA1 encodes a pentatricopeptide repeat protein, which is targeted to the chloroplast. SSA1 regulates early chloroplast development and plays a critical role in RNA editing and intron splicing in rice. These data will facilitate efforts to further elucidate the molecular mechanism of chloroplast biogenesis.
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Affiliation(s)
- Yanwei Wang
- Collage of Food and Biology, Hebei University of Science and Technology, Shijiazhuang, 050018, Hebei, China
| | - Zhimin Yang
- Collage of Food and Biology, Hebei University of Science and Technology, Shijiazhuang, 050018, Hebei, China
| | - Meng Zhang
- Collage of Food and Biology, Hebei University of Science and Technology, Shijiazhuang, 050018, Hebei, China
| | - Pengfei Ai
- Collage of Food and Biology, Hebei University of Science and Technology, Shijiazhuang, 050018, Hebei, China.
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19
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Jan M, Liu Z, Rochaix JD, Sun X. Retrograde and anterograde signaling in the crosstalk between chloroplast and nucleus. FRONTIERS IN PLANT SCIENCE 2022; 13:980237. [PMID: 36119624 PMCID: PMC9478734 DOI: 10.3389/fpls.2022.980237] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 08/18/2022] [Indexed: 06/02/2023]
Abstract
The chloroplast is a complex cellular organelle that not only performs photosynthesis but also synthesizes amino acids, lipids, and phytohormones. Nuclear and chloroplast genetic activity are closely coordinated through signaling chains from the nucleus to chloroplast, referred to as anterograde signaling, and from chloroplast to the nucleus, named retrograde signaling. The chloroplast can act as an environmental sensor and communicates with other cell compartments during its biogenesis and in response to stress, notably with the nucleus through retrograde signaling to regulate nuclear gene expression in response to developmental cues and stresses that affect photosynthesis and growth. Although several components involved in the generation and transmission of plastid-derived retrograde signals and in the regulation of the responsive nuclear genes have been identified, the plastid retrograde signaling network is still poorly understood. Here, we review the current knowledge on multiple plastid retrograde signaling pathways, and on potential plastid signaling molecules. We also discuss the retrograde signaling-dependent regulation of nuclear gene expression within the frame of a multilayered network of transcription factors.
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Affiliation(s)
- Masood Jan
- State Key Laboratory of Cotton Biology and State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
| | - Zhixin Liu
- State Key Laboratory of Cotton Biology and State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
| | - Jean-David Rochaix
- Department of Molecular Biology and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Xuwu Sun
- State Key Laboratory of Cotton Biology and State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
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20
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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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S-Adenosyl-L-Methionine and Cu(II) Impact Green Plant Regeneration Efficiency. Cells 2022; 11:cells11172700. [PMID: 36078107 PMCID: PMC9454820 DOI: 10.3390/cells11172700] [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: 07/18/2022] [Revised: 08/17/2022] [Accepted: 08/25/2022] [Indexed: 11/17/2022] Open
Abstract
The biological improvement of triticale, a cereal of increasing importance in agriculture, may be accelerated via the production of doubled haploid lines using in vitro culture. Among the relevant factors affecting the culture efficiency are Cu(II) or Ag(I) acting, e.g., as cofactors of enzymes. The copper ions are known to positively affect green plant regeneration efficiency. However, the biochemical basis, mainly its role in the generation of in vitro-induced genetic and epigenetic variation and green plant regeneration efficiency, is not well understood. Here, we employed structural equation modeling to evaluate the relationship between de novo DNA methylation affecting the asymmetric context of CHH sequences, the methylation-sensitive Amplified Fragment Length Polymorphism related sequence variation, and the concentration of Cu(II) and Ag(I) ions in induction media, as well as their effect on S-adenosyl-L-methionine perturbations, observed using FTIR spectroscopy, and the green plant regeneration efficiency. Our results allowed the construction of a theory-based model reflecting the biological phenomena associated with green plant regeneration efficiency. Furthermore, it is shown that Cu(II) ions in induction media affect plant regeneration, and by manipulating their concentration, the regeneration efficiency can be altered. Additionally, S-adenosyl-L-methionine is involved in the efficiency of green plant regeneration through methylation of the asymmetric CHH sequence related to de novo methylation. This shows that the Yang cycle may impact the production of green regenerants.
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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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23
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Park SH, Kyndt JA, Brown JK. Comparison of Auxenochlorella protothecoides and Chlorella spp. Chloroplast Genomes: Evidence for Endosymbiosis and Horizontal Virus-like Gene Transfer. Life (Basel) 2022; 12:life12030458. [PMID: 35330209 PMCID: PMC8955559 DOI: 10.3390/life12030458] [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: 02/10/2022] [Revised: 03/15/2022] [Accepted: 03/16/2022] [Indexed: 12/02/2022] Open
Abstract
Resequencing of the chloroplast genome (cpDNA) of Auxenochlorella protothecoides UTEX 25 was completed (GenBank Accession no. KC631634.1), revealing a genome size of 84,576 base pairs and 30.8% GC content, consistent with features reported for the previously sequenced A. protothecoides 0710, (GenBank Accession no. KC843975). The A. protothecoides UTEX 25 cpDNA encoded 78 predicted open reading frames, 32 tRNAs, and 4 rRNAs, making it smaller and more compact than the cpDNA genome of C. variabilis (124,579 bp) and C. vulgaris (150,613 bp). By comparison, the compact genome size of A. protothecoides was attributable primarily to a lower intergenic sequence content. The cpDNA coding regions of all known Chlorella species were found to be organized in conserved colinear blocks, with some rearrangements. The Auxenochlorella and Chlorella species genome structure and composition were similar, and of particular interest were genes influencing photosynthetic efficiency, i.e., chlorophyll synthesis and photosystem subunit I and II genes, consistent with other biofuel species of interest. Phylogenetic analysis revealed that Prototheca cutis is the closest known A. protothecoides relative, followed by members of the genus Chlorella. The cpDNA of A. protothecoides encodes 37 genes that are highly homologous to representative cyanobacteria species, including rrn16, rrn23, and psbA, corroborating a well-recognized symbiosis. Several putative coding regions were identified that shared high nucleotide sequence identity with virus-like sequences, suggestive of horizontal gene transfer. Despite these predictions, no corresponding transcripts were obtained by RT-PCR amplification, indicating they are unlikely to be expressed in the extant lineage.
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Affiliation(s)
- Sang-Hyuck Park
- School of Plant Sciences, The University of Arizona, Tucson, AZ 85721, USA; (S.-H.P.); (J.K.B.)
- Institute of Cannabis Research, Colorado State University-Pueblo, Pueblo, CO 81001, USA
| | - John A. Kyndt
- College of Science and Technology, Bellevue University, Bellevue, NE 68005, USA
- Correspondence:
| | - Judith K. Brown
- School of Plant Sciences, The University of Arizona, Tucson, AZ 85721, USA; (S.-H.P.); (J.K.B.)
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PAP8/pTAC6 Is Part of a Nuclear Protein Complex and Displays RNA Recognition Motifs of Viral Origin. Int J Mol Sci 2022; 23:ijms23063059. [PMID: 35328480 PMCID: PMC8954402 DOI: 10.3390/ijms23063059] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/09/2022] [Accepted: 03/09/2022] [Indexed: 12/13/2022] Open
Abstract
Chloroplast biogenesis depends on a complex transcriptional program involving coordinated expression of plastid and nuclear genes. In particular, photosynthesis-associated plastid genes are expressed by the plastid-encoded polymerase (PEP) that undergoes a structural rearrangement during chloroplast formation. The prokaryotic-type core enzyme is rebuilt into a larger complex by the addition of nuclear-encoded PEP-associated proteins (PAP1 to PAP12). Among the PAPs, some have been detected in the nucleus (PAP5 and PAP8), where they could serve a nuclear function required for efficient chloroplast biogenesis. Here, we detected PAP8 in a large nuclear subcomplex that may include other subunits of the plastid-encoded RNA polymerase. We have made use of PAP8 recombinant proteins in Arabidopsis thaliana to decouple its nucleus- and chloroplast-associated functions and found hypomorphic mutants pointing at essential amino acids. While the origin of the PAP8 gene remained elusive, we have found in its sequence a micro-homologous domain located within a large structural homology with a rhinoviral RNA-dependent RNA polymerase, highlighting potential RNA recognition motifs in PAP8. PAP8 in vitro RNA binding activity suggests that this domain is functional. Hence, we propose that the acquisition of PAPs may have occurred during evolution by different routes, including lateral gene transfer.
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Chen W, Huang J, Chen S, Zhang L, Rochaix JD, Peng L, Xin Q. Stromal Protein Chloroplast Development and Biogenesis1 Is Essential for Chloroplast Development and Biogenesis in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2022; 13:815859. [PMID: 35222475 PMCID: PMC8866770 DOI: 10.3389/fpls.2022.815859] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 01/17/2022] [Indexed: 06/14/2023]
Abstract
Although numerous studies have been carried out on chloroplast development and biogenesis, the underlying regulatory mechanisms are still largely elusive. Here, we characterized a chloroplast stromal protein Chloroplast Development and Biogenesis1 (CDB1). The knockout cdb1 mutant exhibits a seedling-lethal and ivory leaf phenotype. Immunoblot and RNA blot analyses show that accumulation of chloroplast ribosomes is compromised in cdb1, resulting in an almost complete loss of plastid-encoded proteins including the core subunits of the plastid-encoded RNA polymerase (PEP) RpoB and RpoC2, and therefore in impaired PEP activity. Orthologs of CDB1 are found in green algae and land plants. Moreover, a protein shows high similarity with CDB1, designated as CDB1-Like (CDB1L), is present in angiosperms. Absence of CDB1L results in impaired embryo development. While CDB1 is specifically located in the chloroplast stroma, CDB1L is localized in both chloroplasts and mitochondria in Arabidopsis. Thus, our results demonstrate that CDB1 is indispensable for chloroplast development and biogenesis through its involvement in chloroplast ribosome assembly whereas CDB1L may fulfill a similar function in both mitochondria and chloroplasts.
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Affiliation(s)
- Weijie Chen
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Jingang Huang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Shiwei Chen
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Lin Zhang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Jean-David Rochaix
- Departments of Molecular Biology and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Lianwei Peng
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Qiang Xin
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, China
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26
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Lamelas L, Valledor L, López-Hidalgo C, Cañal MJ, Meijón M. Nucleus and chloroplast: A necessary understanding to overcome heat stress in Pinus radiata. PLANT, CELL & ENVIRONMENT 2022; 45:446-458. [PMID: 34855991 DOI: 10.1111/pce.14238] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 11/23/2021] [Accepted: 11/23/2021] [Indexed: 06/13/2023]
Abstract
The recovery and maintenance of plant homeostasis under stressful environments are complex processes involving organelle crosstalk for a coordinated cellular response. Here, we revealed through nuclear and chloroplast subcellular proteomics, biochemical cell profiles and targeted transcriptomics how chloroplasts and nuclei developed their responses under increased temperatures in a long-lived species (Pinus radiata). Parallel to photosynthetic impairment and reactive oxygen species production in the chloroplast, a DNA damage response was triggered in the nucleus followed by an altered chromatin conformation. In addition, in the nuclei, we found several proteins, such as HEMERA or WHIRLY, which change their locations from the chloroplasts to the nuclei carrying the stress message. Additionally, our data showed a deep rearrangement of RNA metabolism in both organelles, revealing microRNAs and AGO1 as potential regulators of the acclimation mechanisms. Altogether, our study highlights the synchronisation among the different stages required for thermotolerance acquisition in P. radiata, pointing out the role of chromatin conformation and posttranscriptional gene regulation in overcoming heat stress and assuring plant survival for the following years.
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Affiliation(s)
- Laura Lamelas
- Plant Physiology, Department of Organisms and Systems Biology, University of Oviedo, Biotechnology Institute of Asturias, Oviedo, Asturias, Spain
| | - Luis Valledor
- Plant Physiology, Department of Organisms and Systems Biology, University of Oviedo, Biotechnology Institute of Asturias, Oviedo, Asturias, Spain
| | - Cristina López-Hidalgo
- Plant Physiology, Department of Organisms and Systems Biology, University of Oviedo, Biotechnology Institute of Asturias, Oviedo, Asturias, Spain
| | - María Jesús Cañal
- Plant Physiology, Department of Organisms and Systems Biology, University of Oviedo, Biotechnology Institute of Asturias, Oviedo, Asturias, Spain
| | - Mónica Meijón
- Plant Physiology, Department of Organisms and Systems Biology, University of Oviedo, Biotechnology Institute of Asturias, Oviedo, Asturias, Spain
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27
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Yang C, Yan W, Chang H, Sun C. Arabidopsis CIA2 and CIL have distinct and overlapping functions in regulating chloroplast and flower development. PLANT DIRECT 2022; 6:e380. [PMID: 35106435 PMCID: PMC8786619 DOI: 10.1002/pld3.380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/14/2021] [Accepted: 12/26/2021] [Indexed: 05/05/2023]
Abstract
Arabidopsis CHLOROPLAST IMPORT APPARATUS 2 (CIA2) and its paralogous protein CIA2-LIKE (CIL) are nuclear transcription factors containing a C-terminal CCT motif. CIA2 promotes the expression of nuclear genes encoding chloroplast-localized translocons and ribosomal proteins, thereby increasing the efficiency of protein import and synthesis in chloroplasts. We have previously reported that CIA2 and CIL form a homodimer or heterodimer through their C-terminal sequences and interact with other nuclear proteins, such as CONSTANS (CO), via their N-terminal sequences, but the function of CIL had remained unclear. In this study, we verified through transgenic cia2 mutant plants expressing the CIL coding sequence that CIL is partially functionally redundant to CIA2 during vegetative growth. We also compared phenotypes and gene expression profiles of wildtype Col-0, cia2, cil, and cia2/cil mutants. Our results indicate that CIA2 and CIL coordinate chloroplast biogenesis and function mainly by upregulating the expression of the nuclear factor GOLDEN2-LIKE 1 (GLK1) and chloroplast transcription-, translation-, protein import-, and photosynthesis-related genes, with CIA2 playing a more crucial role. Furthermore, we compared flowering phenotypes in single, double, and triple mutant plants of co, cia2, and cil. We found that CIA2 and CIL participate in modulating long-day floral development. Notably, CIA2 increases flower number and height of the inflorescence main axis, whereas CIL promotes flowering.
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Affiliation(s)
- Chun‐Yen Yang
- Department of Life SciencesNational Taiwan Normal UniversityTaipeiTaiwan
| | - Wen‐You Yan
- Department of Life SciencesNational Taiwan Normal UniversityTaipeiTaiwan
| | - Hsin‐Yen Chang
- Department of Life SciencesNational Taiwan Normal UniversityTaipeiTaiwan
| | - Chih‐Wen Sun
- Department of Life SciencesNational Taiwan Normal UniversityTaipeiTaiwan
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28
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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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29
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Kong M, Wu Y, Wang Z, Qu W, Lan Y, Chen X, Liu Y, Shahnaz P, Yang Z, Yu Q, Mi H. A Novel Chloroplast Protein RNA Processing 8 Is Required for the Expression of Chloroplast Genes and Chloroplast Development in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2021; 12:700975. [PMID: 34956248 PMCID: PMC8695849 DOI: 10.3389/fpls.2021.700975] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 11/03/2021] [Indexed: 06/14/2023]
Abstract
Chloroplast development involves the coordinated expression of both plastids- and nuclear-encoded genes in higher plants. However, the underlying mechanism still remains largely unknown. In this study, we isolated and characterized an Arabidopsis mutant with an albino lethality phenotype named RNA processing 8 (rp8). Genetic complementation analysis demonstrated that the gene AT4G37920 (RP8) was responsible for the mutated phenotype. The RP8 gene was strongly expressed in photosynthetic tissues at both transcription and translation protein levels. The RP8 protein is localized in the chloroplast and associated with the thylakoid. Disruption of the RP8 gene led to a defect in the accumulation of the rpoA mature transcript, which reduced the level of the RpoA protein, and affected the transcription of PEP-dependent genes. The abundance of the chloroplast rRNA, including 23S, 16S, 4.5S, and 5S rRNA, were reduced in the rp8 mutant, respectively, and the amounts of chloroplast ribosome proteins, such as, PRPS1(uS1c), PRPS5(uS5c), PRPL2 (uL2c), and PRPL4 (uL4c), were substantially decreased in the rp8 mutant, which indicated that knockout of RP8 seriously affected chloroplast translational machinery. Accordingly, the accumulation of photosynthetic proteins was seriously reduced. Taken together, these results indicate that the RP8 protein plays an important regulatory role in the rpoA transcript processing, which is required for the expression of chloroplast genes and chloroplast development in Arabidopsis.
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Affiliation(s)
- Mengmeng Kong
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Yaozong Wu
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Ziyuan Wang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Wantong Qu
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Yixin Lan
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Xin Chen
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Yanyun Liu
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Perveen Shahnaz
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Zhongnan Yang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Qingbo Yu
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Hualing Mi
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
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30
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CAF Proteins Help SOT1 Regulate the Stability of Chloroplast ndhA Transcripts. Int J Mol Sci 2021; 22:ijms222312639. [PMID: 34884441 PMCID: PMC8657633 DOI: 10.3390/ijms222312639] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/20/2021] [Accepted: 11/20/2021] [Indexed: 12/26/2022] Open
Abstract
Protein-mediated RNA stabilization plays profound roles in chloroplast gene expression. Genetic studies have indicated that chloroplast ndhA transcripts, encoding a key subunit of the NADH dehydrogenase-like complex that mediates photosystem I cyclic electron transport and facilitates chlororespiration, are stabilized by PPR53 and its orthologs, but the underlying mechanisms are unclear. Here, we report that CHLOROPLAST RNA SPLICING 2 (CRS2)-ASSOCIATED FACTOR (CAF) proteins activate SUPPRESSOR OF THYLAKOID FORMATION 1 (SOT1), an ortholog of PPR53 in Arabidopsis thaliana, enhancing their affinity for the 5' ends of ndhA transcripts to stabilize these molecules while inhibiting the RNA endonuclease activity of the SOT1 C-terminal SMR domain. In addition, we established that SOT1 improves the splicing efficiency of ndhA by facilitating the association of CAF2 with the ndhA intron, which may be due to the SOT1-mediated stability of the ndhA transcripts. Our findings shed light on the importance of PPR protein interaction partners in moderating RNA metabolism.
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31
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Lee D, Hua L, Khoshravesh R, Giuliani R, Kumar I, Cousins A, Sage TL, Hibberd JM, Brutnell TP. Engineering chloroplast development in rice through cell-specific control of endogenous genetic circuits. PLANT BIOTECHNOLOGY JOURNAL 2021; 19:2291-2303. [PMID: 34328250 PMCID: PMC8541780 DOI: 10.1111/pbi.13660] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/21/2021] [Accepted: 06/25/2021] [Indexed: 05/03/2023]
Abstract
The engineering of C4 photosynthetic activity into the C3 plant rice has the potential to nearly double rice yields. To engineer a two-cell photosynthetic system in rice, the rice bundle sheath (BS) must be rewired to enhance photosynthetic capacity. Here, we show that BS chloroplast biogenesis is enhanced when the transcriptional activator, Oryza sativa Cytokinin GATA transcription factor 1 (OsCGA1), is driven by a vascular specific promoter. Ectopic expression of OsCGA1 resulted in increased BS chloroplast planar area and increased expression of photosynthesis-associated nuclear genes (PhANG), required for the biogenesis of photosynthetically active chloroplasts in BS cells of rice. A further refinement using a DNAse dead Cas9 (dCas9) activation module driven by the same cell-type specific promoter, directed enhanced chloroplast development of the BS cells when gRNA sequences were delivered by the dCas9 module to the promoter of the endogenous OsCGA1 gene. Single gRNA expression was sufficient to mediate the transactivation of both the endogenous gene and a transgenic GUS reporter fused with OsCGA1 promoter. Our results illustrate the potential for tissue-specific dCas9-activation and the co-regulation of genes needed for multistep engineering of C4 rice.
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Affiliation(s)
| | - Lei Hua
- Department of Plant SciencesUniversity of CambridgeCambridgeUK
| | - Roxana Khoshravesh
- Department of Ecology and Evolutionary Biologythe University of TorontoTorontoONCanada
- Department of Biologythe University of New MexicoAlbuquerqueNMUSA
| | - Rita Giuliani
- School of Biological SciencesWashington State UniversityPullmanWAUSA
| | | | - Asaph Cousins
- School of Biological SciencesWashington State UniversityPullmanWAUSA
| | - Tammy L. Sage
- Department of Ecology and Evolutionary Biologythe University of TorontoTorontoONCanada
| | | | - Thomas P. Brutnell
- Donald Danforth Plant Science CenterSt. LouisMOUSA
- Biotechnology Research InstituteChinese Academy of Agricultural SciencesBeijingChina
- Joint Laboratory for Photosynthesis Enhancement and C4 Rice DevelopmentBiotechnology Research InstituteChinese Academy of Agricultural SciencesBeijingChina
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Liu X, Zhang X, Cao R, Jiao G, Hu S, Shao G, Sheng Z, Xie L, Tang S, Wei X, Hu P. CDE4 encodes a pentatricopeptide repeat protein involved in chloroplast RNA splicing and affects chloroplast development under low-temperature conditions in rice. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:1724-1739. [PMID: 34219386 DOI: 10.1111/jipb.13147] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 06/30/2021] [Indexed: 05/24/2023]
Abstract
Pentatricopeptide repeat (PPR) proteins play important roles in the post-transcriptional modification of organellar RNAs in plants. However, the function of most PPR proteins remains unknown. Here, we characterized the rice (Oryza sativa L.) chlorophyll deficient 4 (cde4) mutant which exhibits an albino phenotype during early leaf development, with decreased chlorophyll contents and abnormal chloroplasts at low-temperature (20°C). Positional cloning revealed that CDE4 encodes a P-type PPR protein localized in chloroplasts. In the cde4 mutant, plastid-encoded polymerase (PEP)-dependent transcript levels were significantly reduced, but transcript levels of nuclear-encoded genes were increased compared to wild-type plants at 20°C. CDE4 directly binds to the transcripts of the chloroplast genes rpl2, ndhA, and ndhB. Intron splicing of these transcripts was defective in the cde4 mutant at 20°C, but was normal at 32°C. Moreover, CDE4 interacts with the guanylate kinase VIRESCENT 2 (V2); overexpression of V2 enhanced CDE4 protein stability, thereby rescuing the cde4 phenotype at 20°C. Our results suggest that CDE4 participates in plastid RNA splicing and plays an important role in rice chloroplast development under low-temperature conditions.
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Affiliation(s)
- Xinyong Liu
- State Key Laboratory of Rice Biology, China National Center for Rice Improvement, China National Rice Research Institute, Hangzhou, 310006, China
| | - Xichun Zhang
- State Key Laboratory of Rice Biology, China National Center for Rice Improvement, China National Rice Research Institute, Hangzhou, 310006, China
- Guizhou Rice Research Institute, Guizhou Academy of Agricultural Sciences, Guiyang, 550006, China
| | - Ruijie Cao
- State Key Laboratory of Rice Biology, China National Center for Rice Improvement, China National Rice Research Institute, Hangzhou, 310006, China
| | - Guiai Jiao
- State Key Laboratory of Rice Biology, China National Center for Rice Improvement, China National Rice Research Institute, Hangzhou, 310006, China
| | - Shikai Hu
- State Key Laboratory of Rice Biology, China National Center for Rice Improvement, China National Rice Research Institute, Hangzhou, 310006, China
| | - Gaoneng Shao
- State Key Laboratory of Rice Biology, China National Center for Rice Improvement, China National Rice Research Institute, Hangzhou, 310006, China
| | - Zhonghua Sheng
- State Key Laboratory of Rice Biology, China National Center for Rice Improvement, China National Rice Research Institute, Hangzhou, 310006, China
| | - Lihong Xie
- State Key Laboratory of Rice Biology, China National Center for Rice Improvement, China National Rice Research Institute, Hangzhou, 310006, China
| | - Shaoqing Tang
- State Key Laboratory of Rice Biology, China National Center for Rice Improvement, China National Rice Research Institute, Hangzhou, 310006, China
| | - Xiangjin Wei
- State Key Laboratory of Rice Biology, China National Center for Rice Improvement, China National Rice Research Institute, Hangzhou, 310006, China
| | - Peisong Hu
- State Key Laboratory of Rice Biology, China National Center for Rice Improvement, China National Rice Research Institute, Hangzhou, 310006, China
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Pardi SA, Nusinow DA. Out of the Dark and Into the Light: A New View of Phytochrome Photobodies. FRONTIERS IN PLANT SCIENCE 2021; 12:732947. [PMID: 34531891 PMCID: PMC8438518 DOI: 10.3389/fpls.2021.732947] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 08/05/2021] [Indexed: 05/27/2023]
Abstract
Light is a critical environmental stimulus for plants, serving as an energy source via photosynthesis and a signal for developmental programming. Plants perceive light through various light-responsive proteins, termed photoreceptors. Phytochromes are red-light photoreceptors that are highly conserved across kingdoms. In the model plant Arabidopsis thaliana, phytochrome B serves as a light and thermal sensor, mediating physiological processes such as seedling germination and establishment, hypocotyl growth, chlorophyll biogenesis, and flowering. In response to red light, phytochromes convert to a biologically active form, translocating from the cytoplasm into the nucleus and further compartmentalizes into subnuclear compartments termed photobodies. PhyB photobodies regulate phytochrome-mediated signaling and physiological outputs. However, photobody function, composition, and biogenesis remain undefined since their discovery. Based on photobody cellular dynamics and the properties of internal components, photobodies have been suggested to undergo liquid-liquid phase separation, a process by which some membraneless compartments form. Here, we explore photobodies as environmental sensors, examine the role of their protein constituents, and outline the biophysical perspective that photobodies may be undergoing liquid-liquid phase separation. Understanding the molecular, cellular, and biophysical processes that shape how plants perceive light will help in engineering improved sunlight capture and fitness of important crops.
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Affiliation(s)
- Sarah A. Pardi
- Donald Danforth Plant Science Center, St. Louis, MO, United States
- Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO, United States
| | - Dmitri A. Nusinow
- Donald Danforth Plant Science Center, St. Louis, MO, United States
- Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO, United States
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Abstract
Chloroplasts, the sites of photosynthesis and sources of reducing power, are at the core of the success story that sets apart autotrophic plants from most other living organisms. Along with their fellow organelles (e.g., amylo-, chromo-, etio-, and leucoplasts), they form a group of intracellular biosynthetic machines collectively known as plastids. These plant cell constituents have their own genome (plastome), their own (70S) ribosomes, and complete enzymatic equipment covering the full range from DNA replication via transcription and RNA processive modification to translation. Plastid RNA synthesis (gene transcription) involves the collaborative activity of two distinct types of RNA polymerases that differ in their phylogenetic origin as well as their architecture and mode of function. The existence of multiple plastid RNA polymerases is reflected by distinctive sets of regulatory DNA elements and protein factors. This complexity of the plastid transcription apparatus thus provides ample room for regulatory effects at many levels within and beyond transcription. Research in this field offers insight into the various ways in which plastid genes, both singly and groupwise, can be regulated according to the needs of the entire cell. Furthermore, it opens up strategies that allow to alter these processes in order to optimize the expression of desired gene products.
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Affiliation(s)
- Jennifer Ortelt
- Department of Biology and Biotechnology, University of Bochum, Bochum, Germany
| | - Gerhard Link
- Department of Biology and Biotechnology, University of Bochum, Bochum, Germany.
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Li C, Liu Y, Liu X, Mai KKK, Li J, Guo X, Zhang C, Li H, Kang BH, Hwang I, Lu H. Chloroplast thylakoid ascorbate peroxidase PtotAPX plays a key role in chloroplast development by decreasing hydrogen peroxide in Populus tomentosa. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:4333-4354. [PMID: 33884422 DOI: 10.1093/jxb/erab173] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 04/17/2021] [Indexed: 06/12/2023]
Abstract
Chloroplast development is a complex process that is critical to the growth and development of plants. However, the detailed mechanism of chloroplast development in woody plants remains unclear. In this study, we showed that chloroplasts with elaborate thylakoids could develop from proplastids in the cells of calli derived from leaf tissues of Populus tomentosa upon exposure to light. Chloroplast development was confirmed at the molecular and cellular levels. Transcriptome analysis revealed that genes related to photoreceptors and photosynthesis were significantly up-regulated during chloroplast development in a time-dependent manner. In light-induced chloroplast development, a key process was the removal of hydrogen peroxide, in which thylakoid-localized PtotAPX played a major role; light-induced chloroplast development was enhanced in PtotAPX-overexpressing transgenic P. tomentosa callus with lower levels of hydrogen peroxide, but was suppressed in PtotAPX antisense transgenic callus with higher levels of hydrogen peroxide. Moreover, the suppression of light-induced chloroplast development in PtotAPX antisense transgenic callus was relieved by the exogenous reactive oxygen species scavenging agent N,N'-dimethylthiourea (DMTU). Based on these results, we propose that PtotAPX-mediated removal of reactive oxygen species plays a key role in chloroplast development from proplastids upon exposure to light in P. tomentosa.
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Affiliation(s)
- Conghui Li
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Yadi Liu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Xiatong Liu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Keith Ka Ki Mai
- Centre for Cell and Developmental Biology, State Key Laboratory for Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Jiaxin Li
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Xiaorui Guo
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Chong Zhang
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Hui Li
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Byung-Ho Kang
- Centre for Cell and Developmental Biology, State Key Laboratory for Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Inhwan Hwang
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology (POSTECH), Pohang, South Korea
| | - Hai Lu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
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Hung CY, Zhang J, Bhattacharya C, Li H, Kittur FS, Oldham CE, Wei X, Burkey KO, Chen J, Xie J. Transformation of Long-Lived Albino Epipremnum aureum 'Golden Pothos' and Restoring Chloroplast Development. FRONTIERS IN PLANT SCIENCE 2021; 12:647507. [PMID: 34054894 PMCID: PMC8149757 DOI: 10.3389/fpls.2021.647507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 04/19/2021] [Indexed: 05/27/2023]
Abstract
Chloroplasts are organelles responsible for chlorophyll biosynthesis, photosynthesis, and biosynthesis of many metabolites, which are one of key targets for crop improvement. Elucidating and engineering genes involved in chloroplast development are important approaches for studying chloroplast functions as well as developing new crops. In this study, we report a long-lived albino mutant derived from a popular ornamental plant Epipremnum aureum 'Golden Pothos' which could be used as a model for analyzing the function of genes involved in chloroplast development and generating colorful plants. Albino mutant plants were isolated from regenerated populations of variegated 'Golden Pothos' whose albino phenotype was previously found to be due to impaired expression of EaZIP, encoding Mg-protoporphyrin IX monomethyl ester cyclase. Using petioles of the mutant plants as explants with a traceable sGFP gene, an efficient transformation system was developed. Expressing Arabidopsis CHL27 (a homolog of EaZIP) but not EaZIP in albino plants restored green color and chloroplast development. Interestingly, in addition to the occurrence of plants with solid green color, plants with variegated leaves and pale-yellow leaves were also obtained in the regenerated populations. Nevertheless, our study shows that these long-lived albino plants along with the established efficient transformation system could be used for creating colorful ornamental plants. This system could also potentially be used for investigating physiological processes associated with chlorophyll levels and chloroplast development as well as certain biological activities, which are difficult to achieve using green plants.
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Affiliation(s)
- Chiu-Yueh Hung
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Jianhui Zhang
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Chayanika Bhattacharya
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Hua Li
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Farooqahmed S. Kittur
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Carla E. Oldham
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
| | - Xiangying Wei
- Institute of Oceanography, Minjiang University, Fuzhou, China
| | - Kent O. Burkey
- USDA-ARS Plant Science Research Unit, Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC, United States
| | - Jianjun Chen
- Environmental Horticulture Department, Mid-Florida Research and Education Center, University of Florida, Apopka, FL, United States
| | - Jiahua Xie
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, Durham, NC, United States
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37
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Ji Y, Lehotai N, Zan Y, Dubreuil C, Díaz MG, Strand Å. A fully assembled plastid-encoded RNA polymerase complex detected in etioplasts and proplastids in Arabidopsis. PHYSIOLOGIA PLANTARUM 2021; 171:435-446. [PMID: 33155308 DOI: 10.1111/ppl.13256] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 10/22/2020] [Accepted: 10/23/2020] [Indexed: 06/11/2023]
Abstract
The plastid-encoded genes of higher plants are transcribed by at least two types of RNA polymerases, the nuclear-encoded RNA polymerase (NEP) and the plastid-encoded RNA polymerase (PEP). In mature photosynthesizing leaves, the vast majority of the genes are transcribed by PEP. However, the regulatory mechanisms controlling plastid transcription during early light response is unclear. Chloroplast development is suggested to be associated with a shift in the usage of the primary RNA polymerase from NEP to PEP as the expression of the plastid-encoded photosynthesis genes is induced upon light exposure. Assembly of the PEP complex has been suggested as a rate-limiting step for full activation of plastid-encoded photosynthesis gene expression. However, two sigma factor mutants, sig2 and sig6, with reduced PEP activity, showed significantly lower expression of the plastid-encoded photosynthesis genes already in the dark and during the first hours of light exposure indicating that PEP activity is required for basal expression of plastid-encoded photosynthesis genes in the dark and during early light response. Furthermore, in etioplasts and proplastids a fully assembled PEP complex was revealed on Blue Native PAGE. Our results indicate that a full assembly of the PEP complex is possible in the dark and that PEP drives basal transcriptional activity of plastid-encoded photosynthesis genes in the dark. Assembly of the complex is most likely not a rate-limiting step for full activation of plastid-encoded photosynthesis gene expression which is rather achieved either by the abundance of the PEP complex or by some posttranslational regulation of the individual PEP components.
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Affiliation(s)
- Yan Ji
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, Umeå, Sweden
| | - Nóra Lehotai
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, Umeå, Sweden
| | - Yanjun Zan
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Carole Dubreuil
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, Umeå, Sweden
- CEA-Commissariat à l'Energie Atomique et aux Énergies Alternatives, CEA Tech, Centre Cadarache, 13108 Saint-Paul-lez-Durance, France
| | - Manuel Guinea Díaz
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, Umeå, Sweden
| | - Åsa Strand
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, Umeå, Sweden
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38
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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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GUN1 and Plastid RNA Metabolism: Learning from Genetics. Cells 2020; 9:cells9102307. [PMID: 33081381 PMCID: PMC7602965 DOI: 10.3390/cells9102307] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/12/2020] [Accepted: 10/14/2020] [Indexed: 11/16/2022] Open
Abstract
GUN1 (genomes uncoupled 1), a chloroplast-localized pentatricopeptide repeat (PPR) protein with a C-terminal small mutS-related (SMR) domain, plays a central role in the retrograde communication of chloroplasts with the nucleus. This flow of information is required for the coordinated expression of plastid and nuclear genes, and it is essential for the correct development and functioning of chloroplasts. Multiple genetic and biochemical findings indicate that GUN1 is important for protein homeostasis in the chloroplast; however, a clear and unified view of GUN1′s role in the chloroplast is still missing. Recently, GUN1 has been reported to modulate the activity of the nucleus-encoded plastid RNA polymerase (NEP) and modulate editing of plastid RNAs upon activation of retrograde communication, revealing a major role of GUN1 in plastid RNA metabolism. In this opinion article, we discuss the recently identified links between plastid RNA metabolism and retrograde signaling by providing a new and extended concept of GUN1 activity, which integrates the multitude of functional genetic interactions reported over the last decade with its primary role in plastid transcription and transcript editing.
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40
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Liebers M, Gillet FX, Israel A, Pounot K, Chambon L, Chieb M, Chevalier F, Ruedas R, Favier A, Gans P, Boeri Erba E, Cobessi D, Pfannschmidt T, Blanvillain R. Nucleo-plastidic PAP8/pTAC6 couples chloroplast formation with photomorphogenesis. EMBO J 2020; 39:e104941. [PMID: 33001465 DOI: 10.15252/embj.2020104941] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 09/02/2020] [Accepted: 09/09/2020] [Indexed: 12/29/2022] Open
Abstract
The initial greening of angiosperms involves light activation of photoreceptors that trigger photomorphogenesis, followed by the development of chloroplasts. In these semi-autonomous organelles, construction of the photosynthetic apparatus depends on the coordination of nuclear and plastid gene expression. Here, we show that the expression of PAP8, an essential subunit of the plastid-encoded RNA polymerase (PEP) in Arabidopsis thaliana, is under the control of a regulatory element recognized by the photomorphogenic factor HY5. PAP8 protein is localized and active in both plastids and the nucleus, and particularly required for the formation of late photobodies. In the pap8 albino mutant, phytochrome-mediated signalling is altered, degradation of the chloroplast development repressors PIF1/PIF3 is disrupted, HY5 is not stabilized, and the expression of the photomorphogenesis regulator GLK1 is impaired. PAP8 translocates into plastids via its targeting pre-sequence, interacts with the PEP and eventually reaches the nucleus, where it can interact with another PEP subunit pTAC12/HMR/PAP5. Since PAP8 is required for the phytochrome B-mediated signalling cascade and the reshaping of the PEP activity, it may coordinate nuclear gene expression with PEP-driven chloroplastic gene expression during chloroplast biogenesis.
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Affiliation(s)
- Monique Liebers
- CNRS, CEA, INRA, IRIG-LPCV, Univ. Grenoble-Alpes, Grenoble, France
| | | | - Abir Israel
- CNRS, CEA, INRA, IRIG-LPCV, Univ. Grenoble-Alpes, Grenoble, France
| | - Kevin Pounot
- CNRS, CEA, INRA, IRIG-LPCV, Univ. Grenoble-Alpes, Grenoble, France
| | - Louise Chambon
- CNRS, CEA, INRA, IRIG-LPCV, Univ. Grenoble-Alpes, Grenoble, France
| | - Maha Chieb
- CNRS, CEA, INRA, IRIG-LPCV, Univ. Grenoble-Alpes, Grenoble, France
| | - Fabien Chevalier
- CNRS, CEA, INRA, IRIG-LPCV, Univ. Grenoble-Alpes, Grenoble, France
| | - Rémi Ruedas
- CEA, CNRS, IBS, Univ. Grenoble Alpes, Grenoble, France
| | - Adrien Favier
- CEA, CNRS, IBS, Univ. Grenoble Alpes, Grenoble, France
| | - Pierre Gans
- CEA, CNRS, IBS, Univ. Grenoble Alpes, Grenoble, France
| | | | - David Cobessi
- CEA, CNRS, IBS, Univ. Grenoble Alpes, Grenoble, France
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41
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The Role of Chloroplast Gene Expression in Plant Responses to Environmental Stress. Int J Mol Sci 2020; 21:ijms21176082. [PMID: 32846932 PMCID: PMC7503970 DOI: 10.3390/ijms21176082] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 08/18/2020] [Accepted: 08/20/2020] [Indexed: 12/16/2022] Open
Abstract
Chloroplasts are plant organelles that carry out photosynthesis, produce various metabolites, and sense changes in the external environment. Given their endosymbiotic origin, chloroplasts have retained independent genomes and gene-expression machinery. Most genes from the prokaryotic ancestors of chloroplasts were transferred into the nucleus over the course of evolution. However, the importance of chloroplast gene expression in environmental stress responses have recently become more apparent. Here, we discuss the emerging roles of the distinct chloroplast gene expression processes in plant responses to environmental stresses. For example, the transcription and translation of psbA play an important role in high-light stress responses. A better understanding of the connection between chloroplast gene expression and environmental stress responses is crucial for breeding stress-tolerant crops better able to cope with the rapidly changing environment.
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42
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Pfannschmidt T, Terry MJ, Van Aken O, Quiros PM. Retrograde signals from endosymbiotic organelles: a common control principle in eukaryotic cells. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190396. [PMID: 32362267 DOI: 10.1098/rstb.2019.0396] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Endosymbiotic organelles of eukaryotic cells, the plastids, including chloroplasts and mitochondria, are highly integrated into cellular signalling networks. In both heterotrophic and autotrophic organisms, plastids and/or mitochondria require extensive organelle-to-nucleus communication in order to establish a coordinated expression of their own genomes with the nuclear genome, which encodes the majority of the components of these organelles. This goal is achieved by the use of a variety of signals that inform the cell nucleus about the number and developmental status of the organelles and their reaction to changing external environments. Such signals have been identified in both photosynthetic and non-photosynthetic eukaryotes (known as retrograde signalling and retrograde response, respectively) and, therefore, appear to be universal mechanisms acting in eukaryotes of all kingdoms. In particular, chloroplasts and mitochondria both harbour crucial redox reactions that are the basis of eukaryotic life and are, therefore, especially susceptible to stress from the environment, which they signal to the rest of the cell. These signals are crucial for cell survival, lifespan and environmental adjustment, and regulate quality control and targeted degradation of dysfunctional organelles, metabolic adjustments, and developmental signalling, as well as induction of apoptosis. The functional similarities between retrograde signalling pathways in autotrophic and non-autotrophic organisms are striking, suggesting the existence of common principles in signalling mechanisms or similarities in their evolution. Here, we provide a survey for the newcomers to this field of research and discuss the importance of retrograde signalling in the context of eukaryotic evolution. Furthermore, we discuss commonalities and differences in retrograde signalling mechanisms and propose retrograde signalling as a general signalling mechanism in eukaryotic cells that will be also of interest for the specialist. This article is part of the theme issue 'Retrograde signalling from endosymbiotic organelles'.
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Affiliation(s)
- Thomas Pfannschmidt
- Institute of Botany, Plant Physiology, Leibniz University Hannover, Herrenhäuser Straße 2, 30419 Hannover, Germany
| | - Matthew J Terry
- School of Biological Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Olivier Van Aken
- Department of Biology, Lund University, Sölvegatan 35, 223 62 Lund, Sweden
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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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Krupinska K, Blanco NE, Oetke S, Zottini M. Genome communication in plants mediated by organelle-n-ucleus-located proteins. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190397. [PMID: 32362260 PMCID: PMC7209962 DOI: 10.1098/rstb.2019.0397] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
An increasing number of eukaryotic proteins have been shown to have a dual localization in the DNA-containing organelles, mitochondria and plastids, and/or the nucleus. Regulation of dual targeting and relocation of proteins from organelles to the nucleus offer the most direct means for communication between organelles as well as organelles and nucleus. Most of the mitochondrial proteins of animals have functions in DNA repair and gene expression by modelling of nucleoid architecture and/or chromatin. In plants, such proteins can affect replication and early development. Most plastid proteins with a confirmed or predicted second location in the nucleus are associated with the prokaryotic core RNA polymerase and are required for chloroplast development and light responses. Few plastid–nucleus-located proteins are involved in pathogen defence and cell cycle control. For three proteins, it has been clearly shown that they are first targeted to the organelle and then relocated to the nucleus, i.e. the nucleoid-associated proteins HEMERA and Whirly1 and the stroma-located defence protein NRIP1. Relocation to the nucleus can be experimentally demonstrated by plastid transformation leading to the synthesis of proteins with a tag that enables their detection in the nucleus or by fusions with fluoroproteins in different experimental set-ups. This article is part of the theme issue ‘Retrograde signalling from endosymbiotic organelles’.
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Affiliation(s)
- Karin Krupinska
- Institute of Botany, Christian-Albrechts-University of Kiel, Olshausenstraße 40, 24098 Kiel, Germany
| | - Nicolás E Blanco
- Centre of Photosynthetic and Biochemical Studies, Faculty of Biochemical Science and Pharmacy, National University of Rosario (CEFOBI/UNR-CONICET), Rosario, Argentina
| | - Svenja Oetke
- Institute of Botany, Christian-Albrechts-University of Kiel, Olshausenstraße 40, 24098 Kiel, Germany
| | - Michela Zottini
- Department of Biology, University of Padova, Via U. Bassi 58B, 35131 Padova, Italy
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Zhao X, Huang J, Chory J. Unraveling the Linkage between Retrograde Signaling and RNA Metabolism in Plants. TRENDS IN PLANT SCIENCE 2020; 25:141-147. [PMID: 31791654 DOI: 10.1016/j.tplants.2019.10.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 10/09/2019] [Accepted: 10/23/2019] [Indexed: 05/25/2023]
Abstract
Retrograde signals are signals that originate in organelles to regulate nuclear gene expression. In plant cells, retrograde signaling from both chloroplasts and mitochondria is essential for plant development and growth. Over the past few years, substantial progress has been made in unraveling the linkages between chloroplast retrograde signaling and nuclear RNA metabolism processes or plastidial RNA editing. These findings add to the complexity of the regulation of organelle-to-nucleus communication. Chloroplast development and function rely on the coordinated regulation of chloroplast and nuclear gene expression, especially under stress conditions. A better understanding of retrograde signaling and RNA metabolism, as well as their connection, is essential for breeding stress-tolerant plants to cope with the dynamic and rapidly changing environment.
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Affiliation(s)
- Xiaobo Zhao
- Institute of Nuclear Agricultural Sciences, Key Laboratory of Nuclear Agricultural Sciences of Ministry of Agriculture and Zhejiang Province, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China; Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA 92037, USA; Plant Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
| | - Jianyan Huang
- Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA 92037, USA; Plant Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Joanne Chory
- Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA 92037, USA; Plant Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
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Jiang D, Tang R, Shi Y, Ke X, Wang Y, Che Y, Luan S, Hou X. Arabidopsis Seedling Lethal 1 Interacting With Plastid-Encoded RNA Polymerase Complex Proteins Is Essential for Chloroplast Development. FRONTIERS IN PLANT SCIENCE 2020; 11:602782. [PMID: 33391315 PMCID: PMC7772139 DOI: 10.3389/fpls.2020.602782] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 11/27/2020] [Indexed: 05/16/2023]
Abstract
Mitochondrial transcription termination factors (mTERFs) are highly conserved proteins in metazoans. Plants have many more mTERF proteins than animals. The functions and the underlying mechanisms of plants' mTERFs remain largely unknown. In plants, mTERF family proteins are present in both mitochondria and plastids and are involved in gene expression in these organelles through different mechanisms. In this study, we screened Arabidopsis mutants with pigment-defective phenotypes and isolated a T-DNA insertion mutant exhibiting seedling-lethal and albino phenotypes [seedling lethal 1 (sl1)]. The SL1 gene encodes an mTERF protein localized in the chloroplast stroma. The sl1 mutant showed severe defects in chloroplast development, photosystem assembly, and the accumulation of photosynthetic proteins. Furthermore, the transcript levels of some plastid-encoded proteins were significantly reduced in the mutant, suggesting that SL1/mTERF3 may function in the chloroplast gene expression. Indeed, SL1/mTERF3 interacted with PAP12/PTAC7, PAP5/PTAC12, and PAP7/PTAC14 in the subgroup of DNA/RNA metabolism in the plastid-encoded RNA polymerase (PEP) complex. Taken together, the characterization of the plant chloroplast mTERF protein, SL1/mTERF3, that associated with PEP complex proteins provided new insights into RNA transcription in the chloroplast.
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Affiliation(s)
- Deyuan Jiang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Renjie Tang
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, United States
| | - Yafei Shi
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xiangsheng Ke
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yetao Wang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yufen Che
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, United States
| | - Sheng Luan
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, United States
- Sheng Luan,
| | - Xin Hou
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
- *Correspondence: Xin Hou,
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Xiong HB, Wang J, Huang C, Rochaix JD, Lin FM, Zhang JX, Ye LS, Shi XH, Yu QB, Yang ZN. mTERF8, a Member of the Mitochondrial Transcription Termination Factor Family, Is Involved in the Transcription Termination of Chloroplast Gene psbJ. PLANT PHYSIOLOGY 2020; 182:408-423. [PMID: 31685645 PMCID: PMC6945865 DOI: 10.1104/pp.19.00906] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 10/21/2019] [Indexed: 05/28/2023]
Abstract
Members of the mitochondrial transcription terminator factor (mTERF) family, originally identified in vertebrate mitochondria, are involved in the termination of organellular transcription. In plants, mTERF proteins are mainly localized in chloroplasts and mitochondria. In Arabidopsis (Arabidopsis thaliana), mTERF8/pTAC15 was identified in the plastid-encoded RNA polymerase (PEP) complex, the major RNA polymerase of chloroplasts. In this work, we demonstrate that mTERF8 is associated with the PEP complex. An mTERF8 knockout line displayed a wild-type-like phenotype under standard growth conditions, but showed impaired efficiency of photosystem II electron flow. Transcription of most chloroplast genes was not substantially affected in the mterf8 mutant; however, the level of the psbJ transcript from the psbEFLJ polycistron was increased. RNA blot analysis showed that a larger transcript accumulates in mterf8 than in the wild type. Thus, abnormal transcription and/or RNA processing occur for the psbEFLJ polycistron. Circular reverse transcription PCR and sequence analysis showed that the psbJ transcript terminates 95 nucleotides downstream of the translation stop codon in the wild type, whereas its termination is aberrant in mterf8 Both electrophoresis mobility shift assays and chloroplast chromatin immunoprecipitation analysis showed that mTERF8 specifically binds to the 3' terminal region of psbJ Transcription analysis using the in vitro T7 RNA polymerase system showed that mTERF8 terminates psbJ transcription. Together, these results suggest that mTERF8 is specifically involved in the transcription termination of the chloroplast gene psbJ.
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Affiliation(s)
- Hai-Bo Xiong
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Jing Wang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Chao Huang
- Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha 410128, China
| | - Jean-David Rochaix
- Departments of Molecular Biology and Plant Biology, University of Geneva, 1211 Geneva, Switzerland
| | - Fei-Min Lin
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Jia-Xing Zhang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Lin-Shan Ye
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Xiao-He Shi
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Qing-Bo Yu
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Zhong-Nan Yang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
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Lee S, Joung YH, Kim JK, Do Choi Y, Jang G. An isoform of the plastid RNA polymerase-associated protein FSD3 negatively regulates chloroplast development. BMC PLANT BIOLOGY 2019; 19:524. [PMID: 31775615 PMCID: PMC6882211 DOI: 10.1186/s12870-019-2128-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Accepted: 11/08/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Plastid-encoded RNA polymerase (PEP) plays an essential role in chloroplast development by governing the expression of genes involved in photosynthesis. At least 12 PEP-associated proteins (PAPs), including FSD3/PAP4, regulate PEP activity and chloroplast development by modulating formation of the PEP complex. RESULTS In this study, we identified FSD3S, a splicing variant of FSD3; the FSD3 and FSD3S transcripts encode proteins with identical N-termini, but different C-termini. Characterization of FSD3 and FSD3S proteins showed that the C-terminal region of FSD3S contains a transmembrane domain, which promotes FSD3S localization to the chloroplast membrane but not to nucleoids, in contrast to FSD3, which localizes to the chloroplast nucleoid. We also found that overexpression of FSD3S negatively affects photosynthetic activity and chloroplast development by reducing expression of genes involved in photosynthesis. In addition, FSD3S failed to complement the chloroplast developmental defects in the fsd3 mutant. CONCLUSION These results suggest FSD3 and FSD3S, with their distinct localization patterns, have different functions in chloroplast development, and FSD3S negatively regulates expression of PEP-dependent chloroplast genes, and development of chloroplasts.
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Affiliation(s)
- Sangyool Lee
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186 Republic of Korea
| | - Young Hee Joung
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186 Republic of Korea
| | - Ju-Kon Kim
- Graduate School of International Agricultural Technology and Crop Biotechnology Institute/Green BioScience and Technology, Seoul National University, Pyeongchang, 25354 Republic of Korea
| | - Yang Do Choi
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, 08826 Republic of Korea
- The National Academy of Sciences, Seoul, 06579 Republic of Korea
| | - Geupil Jang
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186 Republic of Korea
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Yokochi Y, Sugiura K, Takemura K, Yoshida K, Hara S, Wakabayashi KI, Kitao A, Hisabori T. Impact of key residues within chloroplast thioredoxin- f on recognition for reduction and oxidation of target proteins. J Biol Chem 2019; 294:17437-17450. [PMID: 31597700 DOI: 10.1074/jbc.ra119.010401] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 10/02/2019] [Indexed: 01/13/2023] Open
Abstract
Thioredoxin (Trx) is a redox-responsive protein that modulates the activities of its target proteins mostly by reducing their disulfide bonds. In chloroplasts, five Trx isoforms (Trx-f, Trx-m, Trx-x, Trx-y, and Trx-z) regulate various photosynthesis-related enzymes with distinct target selectivity. To elucidate the determinants of the target selectivity of each Trx isoform, here we investigated the residues responsible for target recognition by Trx-f, the most well-studied chloroplast-resident Trx. As reported previously, we found that positively-charged residues on the Trx-f surface are involved in the interactions with its targets. Moreover, several residues that are specifically conserved in Trx-f (e.g. Cys-126 and Thr-158) were also involved in interactions with target proteins. The validity of these residues was examined by the molecular dynamics simulation. In addition, we validated the impact of these key residues on target protein reduction by studying (i) Trx-m variants into which we introduced the key residues for Trx-f and (ii) Trx-like proteins, named atypical Cys His-rich Trx 1 (ACHT1) and ACHT2a, that also contain these key residues. These artificial or natural protein variants could reduce Trx-f-specific targets, indicating that the key residues for Trx-f are critical for Trx-f-specific target recognition. Furthermore, we demonstrate that ACHT1 and ACHT2a efficiently oxidize some Trx-f-specific targets, suggesting that its target selectivity also contributes to the oxidative regulation process. Our results reveal the key residues for Trx-f-specific target recognition and uncover ACHT1 and ACHT2a as oxidation factors of their target proteins, providing critical insight into redox regulation of photosynthesis.
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Affiliation(s)
- Yuichi Yokochi
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan.,School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
| | - Kazunori Sugiura
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
| | - Kazuhiro Takemura
- School of Life Science and Technology, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8550, Japan
| | - Keisuke Yoshida
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan.,School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
| | - Satoshi Hara
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
| | - Ken-Ichi Wakabayashi
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan.,School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
| | - Akio Kitao
- School of Life Science and Technology, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8550, Japan
| | - Toru Hisabori
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan .,School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
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50
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Ding S, Zhang Y, Hu Z, Huang X, Zhang B, Lu Q, Wen X, Wang Y, Lu C. mTERF5 Acts as a Transcriptional Pausing Factor to Positively Regulate Transcription of Chloroplast psbEFLJ. MOLECULAR PLANT 2019; 12:1259-1277. [PMID: 31128276 DOI: 10.1016/j.molp.2019.05.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 04/22/2019] [Accepted: 05/16/2019] [Indexed: 05/21/2023]
Abstract
RNA polymerase transcriptional pausing represents a major checkpoint in transcription in bacteria and metazoans, but it is unknown whether this phenomenon occurs in plant organelles. Here, we report that transcriptional pausing occurs in chloroplasts. We found that mTERF5 specifically and positively regulates the transcription of chloroplast psbEFLJ in Arabidopsis thaliana that encodes four key subunits of photosystem II. We found that mTERF5 causes the plastid-encoded RNA polymerase (PEP) complex to pause at psbEFLJ by binding to the +30 to +51 region of double-stranded DNA. Moreover, we revealed that mTERF5 interacts with pTAC6, an essential subunit of the PEP complex, although pTAC6 is not involved in the transcriptional pausing at psbEFLJ. We showed that mTERF5 recruits additional pTAC6 to the transcriptionally paused region of psbEFLJ, and the recruited pTAC6 proteins could be assembled into the PEP complex to regulate psbEFLJ transcription. Taken together, our findings shed light on the role of transcriptional pausing in chloroplast transcription in plants.
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Affiliation(s)
- Shunhua Ding
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Yi Zhang
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhi Hu
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiahe Huang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Bohan Zhang
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qingtao Lu
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Xiaogang Wen
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Yingchun Wang
- University of Chinese Academy of Sciences, Beijing 100049, China; State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Congming Lu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, China.
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