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Robles P, Quesada V. Unveiling the functions of plastid ribosomal proteins in plant development and abiotic stress tolerance. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2022; 189:35-45. [PMID: 36041366 DOI: 10.1016/j.plaphy.2022.07.029] [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: 05/16/2022] [Revised: 07/22/2022] [Accepted: 07/24/2022] [Indexed: 06/15/2023]
Abstract
Translation of mRNAs into proteins is a universal process and ribosomes are the molecular machinery that carries it out. In eukaryotic cells, ribosomes can be found in the cytoplasm, mitochondria, and also in the chloroplasts of photosynthetic organisms. A number of genetic studies have been performed to determine the function of plastid ribosomal proteins (PRPs). Tobacco has been frequently used as a system to study the ribosomal proteins encoded by the chloroplast genome. In contrast, Arabidopsis thaliana and rice are preferentially used models to study the function of nuclear-encoded PRPs by using direct or reverse genetics approaches. The results of these works have provided a relatively comprehensive catalogue of the roles of PRPs in different plant biology aspects, which highlight that some PRPs are essential, while others are not. The latter ones are involved in chloroplast biogenesis, lateral root formation, leaf morphogenesis, plant growth, photosynthesis or chlorophyll synthesis. Furthermore, small gene families encode some PRPs. In the last few years, an increasing number of findings have revealed a close association between PRPs and tolerance to adverse environmental conditions. Sometimes, the same PRP can be involved in both developmental processes and the response to abiotic stress. The aim of this review is to compile and update the findings hitherto published on the functional analysis of PRPs. The study of the phenotypic effects caused by the disruption of PRPs from different species reveals the involvement of PRPs in different biological processes and highlights the significant impact of plastid translation on plant biology.
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Affiliation(s)
- Pedro Robles
- Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202, Elche, Spain
| | - Víctor Quesada
- Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202, Elche, Spain.
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Chen S, Zeng X, Li Y, Qiu S, Peng X, Xie X, Liu Y, Liao C, Tang X, Wu J. The nuclear-encoded plastid ribosomal protein L18s are essential for plant development. FRONTIERS IN PLANT SCIENCE 2022; 13:949897. [PMID: 36212366 PMCID: PMC9538462 DOI: 10.3389/fpls.2022.949897] [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: 05/21/2022] [Accepted: 08/29/2022] [Indexed: 06/16/2023]
Abstract
Plastid ribosomal proteins (PRPs) are necessary components for plastid ribosome biogenesis, playing essential roles in plastid development. The ribosomal protein L18 involved in the assemble of 5S rRNA and 23S rRNA, is vital for E. coli viability, but the functions of its homologs in plant plastid remain elusive. Here, we characterized the functions of the plant plastid ribosomal protein L18s (PRPL18s) in Arabidopsis and rice. AtPRPL18 was ubiquitously expressed in most of the plant tissues, but with higher expression levels in seedling shoots, leaves, and flowers. AtPRPL18 was localized in chloroplast. Genetic and cytological analyses revealed that a loss of function of AtPRPL18 resulted in embryo development arrest at globular stage. However, overexpression of AtPRPL18 did not show any visible phenotypical changes in Arabidopsis. The rice OsPRPL18 was localized in chloroplast. In contrast to AtPRPL18, knockout of OsPRPL18 did not affect embryo development, but led to an albino lethal phenotype at the seedling stage. Cytological analyses showed that chloroplast development was impaired in the osprpl18-1 mutant. Moreover, a loss-function of OsPRPL18 led to defects in plastid ribosome biogenesis and a serious reduction in the efficiency of plastid intron splicing. In all, these results suggested that PRPL18s play critical roles in plastid ribosome biogenesis, plastid intron splicing, and chloroplast development, and are essential for plant survival.
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Affiliation(s)
- Shujing Chen
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Xinhuang Zeng
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Yiqi Li
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Shijun Qiu
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Xiaoqun Peng
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Xinjue Xie
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Yujie Liu
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Chancan Liao
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Xiaoyan Tang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, China
- Shenzhen Institute of Molecular Crop Design, Shenzhen, China
| | - Jianxin Wu
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
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Dupouy G, McDermott E, Cashell R, Scian A, McHale M, Ryder P, de Groot J, Lucca N, Brychkova G, McKeown PC, Spillane C. Plastid ribosome protein L5 is essential for post-globular embryo development in Arabidopsis thaliana. PLANT REPRODUCTION 2022; 35:189-204. [PMID: 35247095 PMCID: PMC9352626 DOI: 10.1007/s00497-022-00440-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Accepted: 02/14/2022] [Indexed: 06/14/2023]
Abstract
Plastid ribosomal proteins (PRPs) can play essential roles in plastid ribosome functioning that affect plant function and development. However, the roles of many PRPs remain unknown, including elucidation of which PRPs are essential or display redundancy. Here, we report that the nuclear-encoded PLASTID RIBOSOMAL PROTEIN L5 (PRPL5) is essential for early embryo development in A. thaliana, as homozygous loss-of-function mutations in the PRPL5 gene impairs chloroplast development and leads to embryo failure to develop past the globular stage. We confirmed the prpl5 embryo-lethal phenotype by generating a mutant CRISPR/Cas9 line and by genetic complementation. As PRPL5 underwent transfer to the nuclear genome early in the evolution of Embryophyta, PRPL5 can be expected to have acquired a chloroplast transit peptide. We identify and validate the presence of an N-terminal chloroplast transit peptide, but unexpectedly also confirm the presence of a conserved and functional Nuclear Localization Signal on the protein C-terminal end. This study highlights the fundamental role of the plastid translation machinery during the early stages of embryo development in plants and raises the possibility of additional roles of plastid ribosomal proteins in the nucleus.
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Affiliation(s)
- Gilles Dupouy
- Genetics and Biotechnology Lab, Plant and AgriBiosciences Research Centre (PABC), Ryan Institute, Aras de Brun, National University of Ireland Galway, University Road, Galway, H91 REW4, Ireland
| | - Emma McDermott
- Genetics and Biotechnology Lab, Plant and AgriBiosciences Research Centre (PABC), Ryan Institute, Aras de Brun, National University of Ireland Galway, University Road, Galway, H91 REW4, Ireland
| | - Ronan Cashell
- Genetics and Biotechnology Lab, Plant and AgriBiosciences Research Centre (PABC), Ryan Institute, Aras de Brun, National University of Ireland Galway, University Road, Galway, H91 REW4, Ireland
| | - Anna Scian
- Genetics and Biotechnology Lab, Plant and AgriBiosciences Research Centre (PABC), Ryan Institute, Aras de Brun, National University of Ireland Galway, University Road, Galway, H91 REW4, Ireland
| | - Marcus McHale
- Genetics and Biotechnology Lab, Plant and AgriBiosciences Research Centre (PABC), Ryan Institute, Aras de Brun, National University of Ireland Galway, University Road, Galway, H91 REW4, Ireland
| | - Peter Ryder
- Genetics and Biotechnology Lab, Plant and AgriBiosciences Research Centre (PABC), Ryan Institute, Aras de Brun, National University of Ireland Galway, University Road, Galway, H91 REW4, Ireland
| | - Joelle de Groot
- Genetics and Biotechnology Lab, Plant and AgriBiosciences Research Centre (PABC), Ryan Institute, Aras de Brun, National University of Ireland Galway, University Road, Galway, H91 REW4, Ireland
| | - Noel Lucca
- Genetics and Biotechnology Lab, Plant and AgriBiosciences Research Centre (PABC), Ryan Institute, Aras de Brun, National University of Ireland Galway, University Road, Galway, H91 REW4, Ireland
| | - Galina Brychkova
- Genetics and Biotechnology Lab, Plant and AgriBiosciences Research Centre (PABC), Ryan Institute, Aras de Brun, National University of Ireland Galway, University Road, Galway, H91 REW4, Ireland
| | - Peter C McKeown
- Genetics and Biotechnology Lab, Plant and AgriBiosciences Research Centre (PABC), Ryan Institute, Aras de Brun, National University of Ireland Galway, University Road, Galway, H91 REW4, Ireland
| | - Charles Spillane
- Genetics and Biotechnology Lab, Plant and AgriBiosciences Research Centre (PABC), Ryan Institute, Aras de Brun, National University of Ireland Galway, University Road, Galway, H91 REW4, Ireland.
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Khatri R, Pant SR, Sharma K, Niraula PM, Lawaju BR, Lawrence KS, Alkharouf NW, Klink VP. Glycine max Homologs of DOESN'T MAKE INFECTIONS 1, 2, and 3 Function to Impair Heterodera glycines Parasitism While Also Regulating Mitogen Activated Protein Kinase Expression. FRONTIERS IN PLANT SCIENCE 2022; 13:842597. [PMID: 35599880 PMCID: PMC9114929 DOI: 10.3389/fpls.2022.842597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 03/21/2022] [Indexed: 06/15/2023]
Abstract
Glycine max root cells developing into syncytia through the parasitic activities of the pathogenic nematode Heterodera glycines underwent isolation by laser microdissection (LM). Microarray analyses have identified the expression of a G. max DOESN'T MAKE INFECTIONS3 (DMI3) homolog in syncytia undergoing parasitism but during a defense response. DMI3 encodes part of the common symbiosis pathway (CSP) involving DMI1, DMI2, and other CSP genes. The identified DMI gene expression, and symbiosis role, suggests the possible existence of commonalities between symbiosis and defense. G. max has 3 DMI1, 12 DMI2, and 2 DMI3 paralogs. LM-assisted gene expression experiments of isolated syncytia under further examination here show G. max DMI1-3, DMI2-7, and DMI3-2 expression occurring during the defense response in the H. glycines-resistant genotypes G.max [Peking/PI548402] and G.max [PI88788] indicating a broad and consistent level of expression of the genes. Transgenic overexpression (OE) of G. max DMI1-3, DMI2-7, and DMI3-2 impairs H. glycines parasitism. RNA interference (RNAi) of G. max DMI1-3, DMI2-7, and DMI3-2 increases H. glycines parasitism. The combined opposite outcomes reveal a defense function for these genes. Prior functional transgenic analyses of the 32-member G. max mitogen activated protein kinase (MAPK) gene family has determined that 9 of them act in the defense response to H. glycines parasitism, referred to as defense MAPKs. RNA-seq analyses of root RNA isolated from the 9 G. max defense MAPKs undergoing OE or RNAi reveal they alter the relative transcript abundances (RTAs) of specific DMI1, DMI2, and DMI3 paralogs. In contrast, transgenically-manipulated DMI1-3, DMI2-7, and DMI3-2 expression influences MAPK3-1 and MAPK3-2 RTAs under certain circumstances. The results show G. max homologs of the CSP, and defense pathway are linked, apparently involving co-regulated gene expression.
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Affiliation(s)
- Rishi Khatri
- Department of Biological Sciences, Mississippi State University, Starkville, MS, United States
| | - Shankar R. Pant
- Department of Biological Sciences, Mississippi State University, Starkville, MS, United States
| | - Keshav Sharma
- Department of Biological Sciences, Mississippi State University, Starkville, MS, United States
| | - Prakash M. Niraula
- Department of Biological Sciences, Mississippi State University, Starkville, MS, United States
| | - Bisho R. Lawaju
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Starkville, MS, United States
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL, United States
| | - Kathy S. Lawrence
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL, United States
| | - Nadim W. Alkharouf
- Department of Computer and Information Sciences, Towson University, Towson, MD, United States
| | - Vincent P. Klink
- Department of Biological Sciences, Mississippi State University, Starkville, MS, United States
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Starkville, MS, United States
- USDA ARS NEA BARC Molecular Plant Pathology Laboratory, Beltsville, MD, United States
- Center for Computational Sciences High Performance Computing Collaboratory, Mississippi State University, Starkville, MS, United States
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Tang X, Shi F, Wang Y, Huang S, Zhao Y, Feng H. Proteomic analysis of a plastid gene encoding RPS4 mutant in Chinese cabbage (Brassica campestris L. ssp. pekinensis). Funct Integr Genomics 2021; 22:113-130. [PMID: 34881421 DOI: 10.1007/s10142-021-00808-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 02/20/2021] [Accepted: 09/18/2021] [Indexed: 10/19/2022]
Abstract
Plastids are important plant cell organelles containing a genome and bacterial-type 70S ribosomes-primarily composed of plastid ribosomal proteins and ribosomal RNAs. In this study, a chlorophyll-deficient mutant (cdm) obtained from double-haploid Chinese cabbage 'FT' was identified as a plastome mutant with an A-to-C base substitution in the plastid gene encoding the ribosomal protein RPS4. To further elucidate the function and regulatory mechanisms of RPS4, a comparative proteomic analysis was conducted between cdm and its wild-type 'FT' plants by isobaric tags and a relative and absolute quantitation (iTRAQ)-based strategy. A total of 6,245 proteins were identified, 540 of which were differentially abundant proteins (DAPs) in the leaves of cdm as compared to those of 'FT'-including 233 upregulated and 307 downregulated proteins. Upregulated DAPs were mainly involved in translation, organonitrogen compound biosynthetic process, ribosomes, and spliceosomes. Meanwhile, downregulated DAPs were mainly involved in photosynthesis, photosynthetic reaction centres, photosynthetic light harvesting, carbon fixation, and chlorophyll binding. These results indicated an important role of RPS4 in the regulation of growth and development of Chinese cabbage, possibly by regulating plastid translation activity by affecting the expression of specific photosynthesis- and cold stress-related proteins. Moreover, a multiple reaction monitoring (MRM) test and quantitative real-time polymerase chain reaction analysis confirmed our iTRAQ results. Quantitative proteomic analysis allowed us to confirm diverse changes in the metabolic pathways between cdm and 'FT' plants. This work provides new insights into the regulation of chlorophyll biosynthesis and photosynthesis in Chinese cabbage.
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Affiliation(s)
- Xiaoyan Tang
- Department of Horticulture, Shenyang Agricultural University, 120 Dongling Road, Shenhe District, Shenyang, 110866, China.,Anhui Provincial Engineering Laboratory of Horticultural Crop Breeding College of Horticulture, Anhui Agricultural University, 130 Changjiang West Road, Shushan District, Hefei, China
| | - Fengyan Shi
- Department of Horticulture, Shenyang Agricultural University, 120 Dongling Road, Shenhe District, Shenyang, 110866, China
| | - Yiheng Wang
- Biotechnology Research Institute, Xiqing District, Tianjin Academy of Agricultural Sciences, Jinjing Road 17 km, Tianjin, 300384, China
| | - Shengnan Huang
- Department of Horticulture, Shenyang Agricultural University, 120 Dongling Road, Shenhe District, Shenyang, 110866, China
| | - Ying Zhao
- Department of Horticulture, Shenyang Agricultural University, 120 Dongling Road, Shenhe District, Shenyang, 110866, China
| | - Hui Feng
- Department of Horticulture, Shenyang Agricultural University, 120 Dongling Road, Shenhe District, Shenyang, 110866, China.
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Ríos-Meléndez S, Valadez-Hernández E, Delgadillo C, Luna-Guevara ML, Martínez-Núñez MA, Sánchez-Pérez M, Martínez-Y-Pérez JL, Arroyo-Becerra A, Cárdenas L, Bibbins-Martínez M, Maldonado-Mendoza IE, Villalobos-López MA. Pseudocrossidium replicatum (Taylor) R.H. Zander is a fully desiccation-tolerant moss that expresses an inducible molecular mechanism in response to severe abiotic stress. PLANT MOLECULAR BIOLOGY 2021; 107:387-404. [PMID: 34189708 PMCID: PMC8648698 DOI: 10.1007/s11103-021-01167-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 06/10/2021] [Indexed: 05/04/2023]
Abstract
KEY MESSAGE The moss Pseudocrossidium replicatum is a desiccation-tolerant species that uses an inducible system to withstand severe abiotic stress in both protonemal and gametophore tissues. Desiccation tolerance (DT) is the ability of cells to recover from an air-dried state. Here, the moss Pseudocrossidium replicatum was identified as a fully desiccation-tolerant (FDT) species. Its gametophores rapidly lost more than 90% of their water content when exposed to a low-humidity atmosphere [23% relative humidity (RH)], but abscisic acid (ABA) pretreatment diminished the final water loss after equilibrium was reached. P. replicatum gametophores maintained good maximum photosystem II (PSII) efficiency (Fv/Fm) for up to two hours during slow dehydration; however, ABA pretreatment induced a faster decrease in the Fv/Fm. ABA also induced a faster recovery of the Fv/Fm after rehydration. Protein synthesis inhibitor treatment before dehydration hampered the recovery of the Fv/Fm when the gametophores were rehydrated after desiccation, suggesting the presence of an inducible protective mechanism that is activated in response to abiotic stress. This observation was also supported by accumulation of soluble sugars in gametophores exposed to ABA or NaCl. Exogenous ABA treatment delayed the germination of P. replicatum spores and induced morphological changes in protonemal cells that resembled brachycytes. Transcriptome analyses revealed the presence of an inducible molecular mechanism in P. replicatum protonemata that was activated in response to dehydration. This study is the first RNA-Seq study of the protonemal tissues of an FDT moss. Our results suggest that P. replicatum is an FDT moss equipped with an inducible molecular response that prepares this species for severe abiotic stress and that ABA plays an important role in this response.
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Affiliation(s)
- Selma Ríos-Meléndez
- Laboratorio de Genómica Funcional y Biotecnología de Plantas, Centro de Investigación en Biotecnología Aplicada, Instituto Politécnico Nacional, C.P. 90700, Tepetitla de Lardizábal, Tlaxcala, México
| | - Emmanuel Valadez-Hernández
- Laboratorio de Genómica Funcional y Biotecnología de Plantas, Centro de Investigación en Biotecnología Aplicada, Instituto Politécnico Nacional, C.P. 90700, Tepetitla de Lardizábal, Tlaxcala, México
| | - Claudio Delgadillo
- Instituto de Biología, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Maria L Luna-Guevara
- Facultad de Ingeniería Química, Benemérita Universidad Autónoma de Puebla, C.P. 72000, Puebla, Puebla, México
| | - Mario A Martínez-Núñez
- UMDI-Sisal, Facultad de Ciencias, Universidad Nacional Autónoma de México, C.P. 97302, Mérida, Yucatán, México
| | - Mishael Sánchez-Pérez
- Unidad de Análisis Bioinformáticos, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, C.P. 62210, Cuernavaca, Morelos, México
| | - José L Martínez-Y-Pérez
- Centro de Investigación en Genética y Ambiente, Universidad Autónoma de Tlaxcala, C.P. 90210, Ixtacuixtla, Tlaxcala, México
| | - Analilia Arroyo-Becerra
- Laboratorio de Genómica Funcional y Biotecnología de Plantas, Centro de Investigación en Biotecnología Aplicada, Instituto Politécnico Nacional, C.P. 90700, Tepetitla de Lardizábal, Tlaxcala, México
| | - Luis Cárdenas
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, C.P. 62210, Cuernavaca, Morelos, México
| | - Martha Bibbins-Martínez
- Laboratorio de Genómica Funcional y Biotecnología de Plantas, Centro de Investigación en Biotecnología Aplicada, Instituto Politécnico Nacional, C.P. 90700, Tepetitla de Lardizábal, Tlaxcala, México
| | - Ignacio E Maldonado-Mendoza
- Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional, Unidad Sinaloa, Instituto Politécnico Nacional, C.P. 81049, Guasave, Sinaloa, México
| | - Miguel Angel Villalobos-López
- Laboratorio de Genómica Funcional y Biotecnología de Plantas, Centro de Investigación en Biotecnología Aplicada, Instituto Politécnico Nacional, C.P. 90700, Tepetitla de Lardizábal, Tlaxcala, México.
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Jeran N, Rotasperti L, Frabetti G, Calabritto A, Pesaresi P, Tadini L. The PUB4 E3 Ubiquitin Ligase Is Responsible for the Variegated Phenotype Observed upon Alteration of Chloroplast Protein Homeostasis in Arabidopsis Cotyledons. Genes (Basel) 2021; 12:genes12091387. [PMID: 34573369 PMCID: PMC8464772 DOI: 10.3390/genes12091387] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 08/31/2021] [Accepted: 09/03/2021] [Indexed: 12/17/2022] Open
Abstract
During a plant's life cycle, plastids undergo several modifications, from undifferentiated pro-plastids to either photosynthetically-active chloroplasts, ezioplasts, chromoplasts or storage organelles, such as amyloplasts, elaioplasts and proteinoplasts. Plastid proteome rearrangements and protein homeostasis, together with intracellular communication pathways, are key factors for correct plastid differentiation and functioning. When plastid development is affected, aberrant organelles are degraded and recycled in a process that involves plastid protein ubiquitination. In this study, we have analysed the Arabidopsis gun1-102 ftsh5-3 double mutant, lacking both the plastid-located protein GUN1 (Genomes Uncoupled 1), involved in plastid-to-nucleus communication, and the chloroplast-located FTSH5 (Filamentous temperature-sensitive H5), a metalloprotease with a role in photosystem repair and chloroplast biogenesis. gun1-102 ftsh5-3 seedlings show variegated cotyledons and true leaves that we attempted to suppress by introgressing second-site mutations in genes involved in: (i) plastid translation, (ii) plastid folding/import and (iii) cytosolic protein ubiquitination. Different phenotypic effects, ranging from seedling-lethality to partial or complete suppression of the variegated phenotype, were observed in the corresponding triple mutants. Our findings indicate that Plant U-Box 4 (PUB4) E3 ubiquitin ligase plays a major role in the target degradation of damaged chloroplasts and is the main contributor to the variegated phenotype observed in gun1-102 ftsh5-3 seedlings.
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Yang X, Wei Y, Shi Y, Han X, Chen S, Yang L, Li H, Sun B, Shi Y. Cucumber Ribosomal Protein CsRPS21 Interacts With P22 Protein of Cucurbit Chlorotic Yellows Virus. Front Microbiol 2021; 12:654697. [PMID: 33995313 PMCID: PMC8116660 DOI: 10.3389/fmicb.2021.654697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 04/07/2021] [Indexed: 11/24/2022] Open
Abstract
Cucurbit chlorotic yellows virus (CCYV) is a cucurbit-infecting crinivirus. RNA silencing can be initiated as a plant defense against viruses. Viruses encode various RNA silencing suppressors to counteract antiviral silencing. P22 protein encoded by RNA1 of CCYV is a silencing suppressor, but its mechanism of action remains unclear. In this study, the cucumber ribosomal-like protein CsRPS21 was found to interact with P22 protein in vitro and in vivo. A conserved CsRPS21 domain was indispensable for its nuclear localization and interaction with P22. Transient expression of CsRPS21 in Nicotiana benthamiana leaves interfered with P22 accumulation and inhibited P22 silencing suppressor activity. CsRPS21 expression in N. benthamiana protoplasts inhibited CCYV accumulation. Increasing numbers of ribosomal proteins are being found to be involved in viral infections of plants. We identified a P22-interacting ribosomal protein, CsRPS21, and uncovered its role in early viral replication and silencing suppressor activity. Our study increases knowledge of the function of ribosomal proteins during viral infection.
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Affiliation(s)
- Xue Yang
- College of Plant Protection, Henan Agricultural University, Zhengzhou, China
| | - Ying Wei
- College of Plant Protection, Henan Agricultural University, Zhengzhou, China
| | - Yajuan Shi
- College of Plant Protection, Henan Agricultural University, Zhengzhou, China
| | - Xiaoyu Han
- College of Plant Protection, Henan Agricultural University, Zhengzhou, China
| | - Siyu Chen
- College of Plant Protection, Henan Agricultural University, Zhengzhou, China
| | - Lingling Yang
- College of Plant Protection, Henan Agricultural University, Zhengzhou, China
| | - Honglian Li
- College of Plant Protection, Henan Agricultural University, Zhengzhou, China
| | - Bingjian Sun
- College of Plant Protection, Henan Agricultural University, Zhengzhou, China
| | - Yan Shi
- College of Plant Protection, Henan Agricultural University, Zhengzhou, China
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9
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Dong X, Duan S, Wang H, Jin H. Plastid ribosomal protein LPE2 is involved in photosynthesis and the response to C/N balance in Arabidopsis thaliana. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2020; 62:1418-1432. [PMID: 31944575 PMCID: PMC7540278 DOI: 10.1111/jipb.12907] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 01/09/2020] [Indexed: 05/31/2023]
Abstract
The balance between cellular carbon (C) and nitrogen (N) must be tightly coordinated to sustain optimal growth and development in plants. In chloroplasts, photosynthesis converts inorganic C to organic C, which is important for maintenance of C content in plant cells. However, little is known about the role of chloroplasts in C/N balance. Here, we identified a nuclear-encoded protein LOW PHOTOSYNTHETIC EFFICIENCY2 (LPE2) that it is required for photosynthesis and C/N balance in Arabidopsis. LPE2 is specifically localized in the chloroplast. Both loss-of-function mutants, lpe2-1 and lpe2-2, showed lower photosynthetic activity, characterized by slower electron transport and lower PSII quantum yield than the wild type. Notably, LPE2 is predicted to encode the plastid ribosomal protein S21 (RPS21). Deficiency of LPE2 significantly perturbed the thylakoid membrane composition and plastid protein accumulation, although the transcription of plastid genes is not affected obviously. More interestingly, transcriptome analysis indicated that the loss of LPE2 altered the expression of C and N response related genes in nucleus, which is confirmed by quantitative real-time-polymerase chain reaction. Moreover, deficiency of LPE2 suppressed the response of C/N balance in physiological level. Taken together, our findings suggest that LPE2 plays dual roles in photosynthesis and the response to C/N balance.
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Affiliation(s)
- Xiaoxiao Dong
- School of Life SciencesSun Yat‐sen UniversityGuangzhou510275China
| | - Sujuan Duan
- School of Life SciencesSun Yat‐sen UniversityGuangzhou510275China
- School of Pharmaceutical SciencesGuangzhou University of Chinese MedicineGuangzhou510006China
| | - Hong‐Bin Wang
- School of Life SciencesSun Yat‐sen UniversityGuangzhou510275China
| | - Hong‐Lei Jin
- School of Pharmaceutical SciencesGuangzhou University of Chinese MedicineGuangzhou510006China
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10
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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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11
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Tadini L, Peracchio C, Trotta A, Colombo M, Mancini I, Jeran N, Costa A, Faoro F, Marsoni M, Vannini C, Aro EM, Pesaresi P. GUN1 influences the accumulation of NEP-dependent transcripts and chloroplast protein import in Arabidopsis cotyledons upon perturbation of chloroplast protein homeostasis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:1198-1220. [PMID: 31648387 DOI: 10.1111/tpj.14585] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 10/09/2019] [Accepted: 10/21/2019] [Indexed: 05/21/2023]
Abstract
Correct chloroplast development and function require co-ordinated expression of chloroplast and nuclear genes. This is achieved through chloroplast signals that modulate nuclear gene expression in accordance with the chloroplast's needs. Genetic evidence indicates that GUN1, a chloroplast-localized pentatricopeptide repeat (PPR) protein with a C-terminal Small MutS-Related (SMR) domain, is involved in integrating multiple developmental and stress-related signals in both young seedlings and adult leaves. Recently, GUN1 was found to interact physically with factors involved in chloroplast protein homeostasis, and with enzymes of tetrapyrrole biosynthesis in adult leaves that function in various retrograde signalling pathways. Here we show that following perturbation of chloroplast protein homeostasis: (i) by growth in lincomycin-containing medium; or (ii) in mutants defective in either the FtsH protease complex (ftsh), plastid ribosome activity (prps21-1 and prpl11-1) or plastid protein import and folding (cphsc70-1), GUN1 influences NEP-dependent transcript accumulation during cotyledon greening and also intervenes in chloroplast protein import.
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Affiliation(s)
- Luca Tadini
- Dipartimento di Bioscienze, Università degli Studi di Milano, 20133, Milano, Italy
| | - Carlotta Peracchio
- Dipartimento di Bioscienze, Università degli Studi di Milano, 20133, Milano, Italy
| | - Andrea Trotta
- Molecular Plant Biology, Department of Biochemistry, University of Turku, 20014, Turku, Finland
| | - Monica Colombo
- Centro Ricerca e Innovazione, Fondazione Edmund Mach, 38010, San Michele all'Adige, Italy
| | - Ilaria Mancini
- Molecular Plant Biology, Department of Biochemistry, University of Turku, 20014, Turku, Finland
| | - Nicolaj Jeran
- Dipartimento di Bioscienze, Università degli Studi di Milano, 20133, Milano, Italy
| | - Alex Costa
- Dipartimento di Bioscienze, Università degli Studi di Milano, 20133, Milano, Italy
| | - Franco Faoro
- Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia, Università degli Studi di Milano, 20133, Milano, Italy
| | - Milena Marsoni
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, via J.H. Dunant 3, 21100, Varese, Italy
| | - Candida Vannini
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, via J.H. Dunant 3, 21100, Varese, Italy
| | - Eva-Mari Aro
- Molecular Plant Biology, Department of Biochemistry, University of Turku, 20014, Turku, Finland
| | - Paolo Pesaresi
- Dipartimento di Bioscienze, Università degli Studi di Milano, 20133, Milano, Italy
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12
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Lu S, Li C, Zhang Y, Zheng Z, Liu D. Functional Disruption of a Chloroplast Pseudouridine Synthase Desensitizes Arabidopsis Plants to Phosphate Starvation. FRONTIERS IN PLANT SCIENCE 2017; 8:1421. [PMID: 28861101 PMCID: PMC5559850 DOI: 10.3389/fpls.2017.01421] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Accepted: 07/31/2017] [Indexed: 05/29/2023]
Abstract
Phosphate (Pi) deficiency is a common nutritional stress of plants in both agricultural and natural ecosystems. Plants respond to Pi starvation in the environment by triggering a suite of biochemical, physiological, and developmental changes that increase survival and growth. The key factors that determine plant sensitivity to Pi starvation, however, are unclear. In this research, we identified an Arabidopsis mutant, dps1, with greatly reduced sensitivity to Pi starvation. The dps1 phenotypes are caused by a mutation in the previously characterized SVR1 (SUPPRESSION OF VARIAGATION 1) gene, which encodes a chloroplast-localized pseudouridine synthase. The mutation of SVR1 results in defects in chloroplast rRNA biogenesis, which subsequently reduces chloroplast translation. Another mutant, rps5, which contains a mutation in the chloroplast ribosomal protein RPS5 and has reduced chloroplast translation, also displayed decreased sensitivity to Pi starvation. Furthermore, wild type plants treated with lincomycin, a chemical inhibitor of chloroplast translation, showed similar growth phenotypes and Pi starvation responses as dps1 and rps5. These results suggest that impaired chloroplast translation desensitizes plants to Pi starvation. Combined with previously published results showing that enhanced leaf photosynthesis augments plant responses to Pi starvation, we propose that the decrease in responses to Pi starvation in dps1, rps5, and lincomycin-treated plants is due to their reduced demand for Pi input from the environment.
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Affiliation(s)
| | | | | | | | - Dong Liu
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua UniversityBeijing, China
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13
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Zhang J, Yuan H, Yang Y, Fish T, Lyi SM, Thannhauser TW, Zhang L, Li L. Plastid ribosomal protein S5 is involved in photosynthesis, plant development, and cold stress tolerance in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:2731-44. [PMID: 27006483 PMCID: PMC4861020 DOI: 10.1093/jxb/erw106] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Plastid ribosomal proteins are essential components of protein synthesis machinery and have diverse roles in plant growth and development. Mutations in plastid ribosomal proteins lead to a range of developmental phenotypes in plants. However, how they regulate these processes is not fully understood, and the functions of some individual plastid ribosomal proteins remain unknown. To identify genes responsible for chloroplast development, we isolated and characterized a mutant that exhibited pale yellow inner leaves with a reduced growth rate in Arabidopsis. The mutant (rps5) contained a missense mutation of plastid ribosomal protein S5 (RPS5), which caused a dramatically reduced abundance of chloroplast 16S rRNA and seriously impaired 16S rRNA processing to affect ribosome function and plastid translation. Comparative proteomic analysis revealed that the rps5 mutation suppressed the expression of a large number of core components involved in photosystems I and II as well as many plastid ribosomal proteins. Unexpectedly, a number of proteins associated with cold stress responses were greatly decreased in rps5, and overexpression of the plastid RPS5 improved plant cold stress tolerance. Our results indicate that RPS5 is an important constituent of the plastid 30S subunit and affects proteins involved in photosynthesis and cold stress responses to mediate plant growth and development.
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Affiliation(s)
- Junxiang Zhang
- College of Horticulture, State Key Laboratory of Crop Stress Biology for Arid Area, Northwest A&F University, Yangling, 712100, China Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA
| | - Hui Yuan
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA
| | - Yong Yang
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA
| | - Tara Fish
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA
| | - Sangbom M Lyi
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA
| | - Theodore W Thannhauser
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA
| | - Lugang Zhang
- College of Horticulture, State Key Laboratory of Crop Stress Biology for Arid Area, Northwest A&F University, Yangling, 712100, China
| | - Li Li
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY 14853, USA
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14
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Ma Z, Wu W, Huang W, Huang J. Down-regulation of specific plastid ribosomal proteins suppresses thf1 leaf variegation, implying a role of THF1 in plastid gene expression. PHOTOSYNTHESIS RESEARCH 2015; 126:301-310. [PMID: 25733183 DOI: 10.1007/s11120-015-0101-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Accepted: 02/13/2015] [Indexed: 06/04/2023]
Abstract
Chloroplast development is regulated by many biological processes. However, these processes are not fully understood. Leaf variegation mutants have been used as powerful models to elucidate the genetic network of chloroplast development since the degree of leaf variegation is regulated by developmental and environmental cues. The thylakoid formation 1 (thf1) mutant is unique for its variegation in both leaves and cotyledons. Here, we reported a new suppressor gene of thf1 leaf variegation, designated sot8. Map-based cloning and DNA sequencing results showed that a single nucleotide mutation from G to A was detected in the second exon of the gene encoding the ribosomal protein small subunit 9 (PRPS9) in sot8-1, resulting in an amino acid change and a partial loss of PRPS9 function. However, sot8-1 was unable to rescue the thf1 phenotype in low photosystem II activity (Fv/Fm). In addition, we identified two T-DNA insertion mutants defective in plastid-specific ribosomal proteins (PSRPs), psrp2-1, and psrp5-1. Genetic analysis showed that knockdown of PSRP5 expression but not PSRP2 expression suppressed leaf variegation. Northern blotting results showed that precursors of plastid rRNAs over-accumulated in prps9-1 and psrp5-1, indicating that mutations in PRPS9 and PSRP5 cause a defect in rRNA processing. Consistently, inhibition of plastid protein synthesis by spectinomycin led to increased levels of plastid rRNA precursors in wild-type plants, suggesting that rRNA processing and plastid ribosomal assembly are coupled. Taken together, our data indicate that downregulating the expression of specific plastid ribosomal proteins suppresses thf1 leaf variegation, and provide new insights into a role of THF1 in plastid gene expression.
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Affiliation(s)
- Zhaoxue Ma
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Wenjuan Wu
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Weihua Huang
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Jirong Huang
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.
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15
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Gupta A, Shah P, Haider A, Gupta K, Siddiqi MI, Ralph SA, Habib S. Reduced ribosomes of the apicoplast and mitochondrion of Plasmodium spp. and predicted interactions with antibiotics. Open Biol 2015; 4:140045. [PMID: 24850912 PMCID: PMC4042851 DOI: 10.1098/rsob.140045] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Apicomplexan protists such as Plasmodium and Toxoplasma contain a mitochondrion and a relic plastid (apicoplast) that are sites of protein translation. Although there is emerging interest in the partitioning and function of translation factors that participate in apicoplast and mitochondrial peptide synthesis, the composition of organellar ribosomes remains to be elucidated. We carried out an analysis of the complement of core ribosomal protein subunits that are encoded by either the parasite organellar or nuclear genomes, accompanied by a survey of ribosome assembly factors for the apicoplast and mitochondrion. A cross-species comparison with other apicomplexan, algal and diatom species revealed compositional differences in apicomplexan organelle ribosomes and identified considerable reduction and divergence with ribosomes of bacteria or characterized organelle ribosomes from other organisms. We assembled structural models of sections of Plasmodium falciparum organellar ribosomes and predicted interactions with translation inhibitory antibiotics. Differences in predicted drug–ribosome interactions with some of the modelled structures suggested specificity of inhibition between the apicoplast and mitochondrion. Our results indicate that Plasmodium and Toxoplasma organellar ribosomes have a unique composition, resulting from the loss of several large and small subunit proteins accompanied by significant sequence and size divergences in parasite orthologues of ribosomal proteins.
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Affiliation(s)
- Ankit Gupta
- Division of Molecular and Structural Biology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Priyanka Shah
- Division of Molecular and Structural Biology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Afreen Haider
- Division of Molecular and Structural Biology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Kirti Gupta
- Division of Molecular and Structural Biology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Mohammad Imran Siddiqi
- Division of Molecular and Structural Biology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Stuart A Ralph
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria 3010, Australia
| | - Saman Habib
- Division of Molecular and Structural Biology, CSIR-Central Drug Research Institute, Lucknow, India
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16
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Tiller N, Bock R. The translational apparatus of plastids and its role in plant development. MOLECULAR PLANT 2014; 7:1105-20. [PMID: 24589494 PMCID: PMC4086613 DOI: 10.1093/mp/ssu022] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 02/26/2014] [Indexed: 05/18/2023]
Abstract
Chloroplasts (plastids) possess a genome and their own machinery to express it. Translation in plastids occurs on bacterial-type 70S ribosomes utilizing a set of tRNAs that is entirely encoded in the plastid genome. In recent years, the components of the chloroplast translational apparatus have been intensely studied by proteomic approaches and by reverse genetics in the model systems tobacco (plastid-encoded components) and Arabidopsis (nucleus-encoded components). This work has provided important new insights into the structure, function, and biogenesis of chloroplast ribosomes, and also has shed fresh light on the molecular mechanisms of the translation process in plastids. In addition, mutants affected in plastid translation have yielded strong genetic evidence for chloroplast genes and gene products influencing plant development at various levels, presumably via retrograde signaling pathway(s). In this review, we describe recent progress with the functional analysis of components of the chloroplast translational machinery and discuss the currently available evidence that supports a significant impact of plastid translational activity on plant anatomy and morphology.
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Affiliation(s)
- Nadine Tiller
- 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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17
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Takada H, Morita M, Shiwa Y, Sugimoto R, Suzuki S, Kawamura F, Yoshikawa H. Cell motility and biofilm formation in Bacillus subtilis are affected by the ribosomal proteins, S11 and S21. Biosci Biotechnol Biochem 2014; 78:898-907. [PMID: 25035996 DOI: 10.1080/09168451.2014.915729] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Bacillus subtilis differentiates into various cellular states in response to environmental changes. It exists in two states during the exponential growth phase: motile cells and connected chains of sessile cells. Here, we identified new regulators of cell motility and chaining, the ribosomal proteins S21 (rpsU) and S11 (rpsK). Their mutants showed impaired cell motility (observed in a laboratory strain) and robust biofilm formation (observed in an undomesticated strain). The two major operons for biofilm formation, tapA-sipW-tasA and epsA-O, were strongly expressed in the rpsU mutant, whereas the flagellin-encoding hag gene and other SigD-dependent motility regulons were not. Genetic analysis revealed that the mutation of remA, the transcriptional activator of the eps operon, is epistatic to that of rpsU, whereas the mutation of antagonistic regulators of SinR is not. Our studies demonstrate that S11 and S21 participate in the regulation of bistability via the RemA/RemB pathway.
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Affiliation(s)
- Hiraku Takada
- a Department of Bioscience , Tokyo University of Agriculture , Tokyo , Japan
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18
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Song J, Wei X, Shao G, Sheng Z, Chen D, Liu C, Jiao G, Xie L, Tang S, Hu P. The rice nuclear gene WLP1 encoding a chloroplast ribosome L13 protein is needed for chloroplast development in rice grown under low temperature conditions. PLANT MOLECULAR BIOLOGY 2014; 84:301-14. [PMID: 24132771 DOI: 10.1007/s11103-013-0134-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2013] [Accepted: 09/23/2013] [Indexed: 05/22/2023]
Abstract
Plastidial ribosome proteins (PRPs) form the major component of the plastidial ribosome. Here we describe a rice mutant named wlp1 (white leaf and panicles 1) selected from a population of tissue culture regenerants. The early seedling leaves of the mutant were albino, as was the immature panicle at heading, and the phenotype was more strongly expressed in plants exposed to low temperature conditions. Changes in the leaf pigmentation of the mutant were due to altered chlorophyll content and chloroplast development. Positional cloning of WLP1, followed by complementation and knock-down experiments, showed that it encodes a 50S ribosome L13 protein. The WLP1 protein localized to the chloroplast. WLP1 was mainly transcribed in green tissues and particularly abundantly in the early seedling leaves. In addition, the expression level of WLP1 was induced by the low temperature. The transcription pattern of a number of genes involved in plastidial transcription/translation and in photosynthesis was altered in the wlp1 mutants. These results reveal that WLP1 is required for normal chloroplast development, especially under low temperature conditions. This is the first report on the function of PRPs in rice.
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Affiliation(s)
- Jian Song
- State Key Laboratory of Rice Biology, Key Laboratory of Rice Biology and Breeding of Ministry of Agriculture, China National Rice Research Institute, Hangzhou, 310006, China
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19
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Liu X, Zheng M, Wang R, Wang R, An L, Rodermel SR, Yu F. Genetic interactions reveal that specific defects of chloroplast translation are associated with the suppression of var2-mediated leaf variegation. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2013; 55:979-93. [PMID: 23721655 DOI: 10.1111/jipb.12078] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 05/21/2013] [Indexed: 05/09/2023]
Abstract
Arabidopsis thaliana L. yellow variegated (var2) mutant is defective in a chloroplast FtsH family metalloprotease, AtFtsH2/VAR2, and displays an intriguing green and white leaf variegation. This unique var2-mediated leaf variegation offers a simple yet powerful tool for dissecting the genetic regulation of chloroplast development. Here, we report the isolation and characterization of a new var2 suppressor gene, SUPPRESSOR OF VARIEGATION8 (SVR8), which encodes a putative chloroplast ribosomal large subunit protein, L24. Mutations in SVR8 suppress var2 leaf variegation at ambient temperature and partially suppress the cold-induced chlorosis phenotype of var2. Loss of SVR8 causes unique chloroplast rRNA processing defects, particularly the 23S-4.5S dicistronic precursor. The recovery of the major abnormal processing site in svr8 23S-4.5S precursor indicate that it does not lie in the same position where SVR8/L24 binds on the ribosome. Surprisingly, we found that the loss of a chloroplast ribosomal small subunit protein, S21, results in aberrant chloroplast rRNA processing but not suppression of var2 variegation. These findings suggest that the disruption of specific aspects of chloroplast translation, rather than a general impairment in chloroplast translation, suppress var2 variegation and the existence of complex genetic interactions in chloroplast development.
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Affiliation(s)
- Xiayan Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, 712100, China
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20
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Comparative proteomic analysis of embryos between a maize hybrid and its parental lines during early stages of seed germination. PLoS One 2013; 8:e65867. [PMID: 23776561 PMCID: PMC3679168 DOI: 10.1371/journal.pone.0065867] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 04/29/2013] [Indexed: 11/19/2022] Open
Abstract
In spite of commercial use of heterosis in agriculture, the molecular basis of heterosis is poorly understood. It was observed that maize hybrid Zong3/87-1 exhibited an earlier onset or heterosis in radicle emergence. To get insights into the underlying mechanism of heterosis in radicle emergence, differential proteomic analysis between hybrid and its parental lines was performed. In total, the number of differentially expressed protein spots between hybrid and its parental lines in dry and 24 h imbibed seed embryos were 134 and 191, respectively, among which 47.01% (63/134) and 34.55% (66/191) protein spots displayed nonadditively expressed pattern. Remarkably, 54.55% of nonadditively accumulated proteins in 24 h imbibed seed embryos displayed above or equal to the level of the higher parent patterns. Moreover, 155 differentially expressed protein spots were identified, which were grouped into eight functional classes, including transcription & translation, energy & metabolism, signal transduction, disease & defense, storage protein, transposable element, cell growth & division and unclassified proteins. In addition, one of the upregulated proteins in F1 hybrids was ZmACT2, a homolog of Arabidopsis thaliana ACT7 (AtACT7). Expressing ZmACT2 driven by the AtACT7 promoter partially complemented the low germination phenotype in the Atact7 mutant. These results indicated that hybridization between two parental lines can cause changes in the expression of a variety of proteins, and it is concluded that the altered pattern of gene expression at translational level in the hybrid may be responsible for the observed heterosis.
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21
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Romani I, Tadini L, Rossi F, Masiero S, Pribil M, Jahns P, Kater M, Leister D, Pesaresi P. Versatile roles of Arabidopsis plastid ribosomal proteins in plant growth and development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 72:922-34. [PMID: 22900828 DOI: 10.1111/tpj.12000] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
A lack of individual plastid ribosomal proteins (PRPs) can have diverse phenotypic effects in Arabidopsis thaliana, ranging from embryo lethality to compromised vitality, with the latter being associated with photosynthetic lesions and decreases in the expression of plastid proteins. In this study, reverse genetics was employed to study the function of eight PRPs, five of which (PRPS1, -S20, -L27, -L28 and -L35) have not been functionally characterised before. In the case of PRPS17, only leaky alleles or RNA interference lines had been analysed previously. PRPL1 and PRPL4 have been described as essential for embryo development, but their mutant phenotypes are analysed in detail here. We found that PRPS20, -L1, -L4, -L27 and -L35 are required for basal ribosome activity, which becomes crucial at the globular stage and during the transition from the globular to the heart stage of embryogenesis. Thus, lack of any of these PRPs leads to alterations in cell division patterns, and embryo development ceases prior to the heart stage. PRPL28 is essential at the latest stages of embryo-seedling development, during the greening process. PRPS1, -S17 and -L24 appear not to be required for basal ribosome activity and the organism can complete its entire life cycle in their absence. Interestingly, despite the prokaryotic origin of plastids, the significance of individual PRPs for plant development cannot be predicted from the relative phenotypic severity of the corresponding mutants in prokaryotic systems.
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Affiliation(s)
- Isidora Romani
- Dipartimento di Bioscienze, Università degli studi di Milano, I-20133 Milano, ItalyLehrstuhl für Molekularbiologie der Pflanzen (Botanik), Department Biologie I, Ludwig-Maximilians-Universität München, D-82152 Planegg-Martinsried, GermanyPlant Biochemistry, Heinrich-Heine-University Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
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22
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Yin T, Pan G, Liu H, Wu J, Li Y, Zhao Z, Fu T, Zhou Y. The chloroplast ribosomal protein L21 gene is essential for plastid development and embryogenesis in Arabidopsis. PLANTA 2012; 235:907-21. [PMID: 22105802 DOI: 10.1007/s00425-011-1547-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Accepted: 10/31/2011] [Indexed: 05/22/2023]
Abstract
Embryogenesis in higher plants is controlled by a complex gene network. Identification and characterization of genes essential for embryogenesis will provide insights into the early events in embryo development. In this study, a novel mutant with aborted seed development (asd) was identified in Arabidopsis. The asd mutant produced about 25% of albino seeds at the early stage of silique development. The segregation of normal and albino seeds was inherited as a single recessive embryo-lethal trait. The gene disrupted in the asd mutant was isolated through map-based cloning. The mutated gene contains a single base change (A to C) in the coding region of RPL21C (At1g35680) that is predicted to encode the chloroplast 50S ribosomal protein L21. Allele test with other two T-DNA insertion lines in RPL21C and a complementation test demonstrated that the mutation in RPL21C was responsible for the asd phenotype. RPL21C exhibits higher expression in leaves and flowers compared with expression levels in roots and developing seeds. The RPL21C-GFP fusion protein was localized in chloroplasts. Cytological observations showed that the asd embryo development was arrested at the globular stage. There were no plastids with normal thylakoids and as a result no normal chloroplasts formed in mutant cells, indicating an indispensable role of the ASD gene in chloroplasts biogenesis. Our studies suggest that the chloroplast ribosomal protein L21 gene is required for chloroplast development and embryogenesis in Arabidopsis.
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Affiliation(s)
- Tuanzhang Yin
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
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Tiller N, Weingartner M, Thiele W, Maximova E, Schöttler MA, Bock R. The plastid-specific ribosomal proteins of Arabidopsis thaliana can be divided into non-essential proteins and genuine ribosomal proteins. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 69:302-16. [PMID: 21923745 DOI: 10.1111/j.1365-313x.2011.04791.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Plastid translation occurs on bacterial-type 70S ribosomes consisting of a large (50S) subunit and a small (30S) subunit. The vast majority of plastid ribosomal proteins have orthologs in bacteria. In addition, plastids also possess a small set of unique ribosomal proteins, so-called plastid-specific ribosomal proteins (PSRPs). The functions of these PSRPs are unknown, but, based on structural studies, it has been proposed that they may represent accessory proteins involved in translational regulation. Here we have investigated the functions of five PSRPs using reverse genetics in the model plant Arabidopsis thaliana. By analyzing T-DNA insertion mutants and RNAi lines, we show that three PSRPs display characteristics of genuine ribosomal proteins, in that down-regulation of their expression led to decreased accumulation of the 30S or 50S subunit of the plastid ribosomes, resulting in plastid translational deficiency. In contrast, two other PSRPs can be knocked out without visible or measurable phenotypic consequences. Our data suggest that PSRPs fall into two types: (i) PSRPs that have a structural role in the ribosome and are bona fide ribosomal proteins, and (ii) non-essential PSRPs that are not required for stable ribosome accumulation and translation under standard greenhouse conditions.
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Affiliation(s)
- Nadine Tiller
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
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Hofmann J, Börnke F, Schmiedl A, Kleine T, Sonnewald U. Detecting functional groups of Arabidopsis mutants by metabolic profiling and evaluation of pleiotropic responses. FRONTIERS IN PLANT SCIENCE 2011; 2:82. [PMID: 22639613 PMCID: PMC3355665 DOI: 10.3389/fpls.2011.00082] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Accepted: 11/02/2011] [Indexed: 06/01/2023]
Abstract
Metabolic profiles and fingerprints of Arabidopsis thaliana plants with various defects in plastidic sugar metabolism or photosynthesis were analyzed to elucidate if the genetic mutations can be traced by comparing their metabolic status. Using a platform of chromatographic and spectrometric tools data from untargeted full MS scans as well as from selected metabolites including major carbohydrates, phosphorylated intermediates, carboxylates, free amino acids, major antioxidants, and plastidic pigments were evaluated. Our key observations are that by multivariate statistical analysis each mutant can be separated by a unique metabolic signature. Closely related mutants come close. Thus metabolic profiles of sugar mutants are different but more similar than those of photosynthesis mutants. All mutants show pleiotropic responses mirrored in their metabolic status. These pleiotropic responses are typical and can be used for separating and grouping of the mutants. Our findings show that metabolite fingerprints can be taken to classify mutants and hence may be used to sort genes into functional groups.
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Affiliation(s)
- Jörg Hofmann
- Division of Biochemistry, Department Biology, Friedrich-Alexander-Universität Erlangen-NurembergErlangen, Germany
| | - Frederik Börnke
- Division of Biochemistry, Department Biology, Friedrich-Alexander-Universität Erlangen-NurembergErlangen, Germany
| | - Alfred Schmiedl
- Division of Biochemistry, Department Biology, Friedrich-Alexander-Universität Erlangen-NurembergErlangen, Germany
| | - Tatjana Kleine
- Biochemistry and Plant Physiology (Botany), Department Biology I, Ludwig-Maximilians-Universität MünchenPlanegg-Martinsried, Germany
| | - Uwe Sonnewald
- Division of Biochemistry, Department Biology, Friedrich-Alexander-Universität Erlangen-NurembergErlangen, Germany
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Bryant N, Lloyd J, Sweeney C, Myouga F, Meinke D. Identification of nuclear genes encoding chloroplast-localized proteins required for embryo development in Arabidopsis. PLANT PHYSIOLOGY 2011; 155:1678-89. [PMID: 21139083 PMCID: PMC3091104 DOI: 10.1104/pp.110.168120] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Accepted: 11/29/2010] [Indexed: 05/18/2023]
Abstract
We describe here the diversity of chloroplast proteins required for embryo development in Arabidopsis (Arabidopsis thaliana). Interfering with certain chloroplast functions has long been known to result in embryo lethality. What has not been reported before is a comprehensive screen for embryo-defective (emb) mutants altered in chloroplast proteins. From a collection of transposon and T-DNA insertion lines at the RIKEN chloroplast function database (http://rarge.psc.riken.jp/chloroplast/) that initially appeared to lack homozygotes and segregate for defective seeds, we identified 23 additional examples of EMB genes that likely encode chloroplast-localized proteins. Fourteen gene identities were confirmed with allelism tests involving duplicate mutant alleles. We then queried journal publications and the SeedGenes database (www.seedgenes.org) to establish a comprehensive dataset of 381 nuclear genes encoding chloroplast proteins of Arabidopsis associated with embryo-defective (119 genes), plant pigment (121 genes), gametophyte (three genes), and alternate (138 genes) phenotypes. Loci were ranked based on the level of certainty that the gene responsible for the phenotype had been identified and the protein product localized to chloroplasts. Embryo development is frequently arrested when amino acid, vitamin, or nucleotide biosynthesis is disrupted but proceeds when photosynthesis is compromised and when levels of chlorophyll, carotenoids, or terpenoids are reduced. Chloroplast translation is also required for embryo development, with genes encoding chloroplast ribosomal and pentatricopeptide repeat proteins well represented among EMB datasets. The chloroplast accD locus, which is necessary for fatty acid biosynthesis, is essential in Arabidopsis but not in Brassica napus or maize (Zea mays), where duplicated nuclear genes compensate for its absence or loss of function.
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Whittle CA, Krochko JE. Transcript profiling provides evidence of functional divergence and expression networks among ribosomal protein gene paralogs in Brassica napus. THE PLANT CELL 2009; 21:2203-19. [PMID: 19706795 PMCID: PMC2751962 DOI: 10.1105/tpc.109.068411] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 06/14/2009] [Accepted: 07/15/2009] [Indexed: 05/19/2023]
Abstract
The plant ribosome is composed of 80 distinct ribosomal (r)-proteins. In Arabidopsis thaliana, each r-protein is encoded by two or more highly similar paralogous genes, although only one copy of each r-protein is incorporated into the ribosome. Brassica napus is especially suited to the comparative study of r-protein gene paralogs due to its documented history of genome duplication as well as the recent availability of large EST data sets. We have identified 996 putative r-protein genes spanning 79 distinct r-proteins in B. napus using EST data from 16 tissue collections. A total of 23,408 tissue-specific r-protein ESTs are associated with this gene set. Comparative analysis of the transcript levels for these unigenes reveals that a large fraction of r-protein genes are differentially expressed and that the number of paralogs expressed for each r-protein varies extensively with tissue type in B. napus. In addition, in many cases the paralogous genes for a specific r-protein are not transcribed in concert and have highly contrasting expression patterns among tissues. Thus, each tissue examined has a novel r-protein transcript population. Furthermore, hierarchical clustering reveals that particular paralogs for nonhomologous r-protein genes cluster together, suggesting that r-protein paralog combinations are associated with specific tissues in B. napus and, thus, may contribute to tissue differentiation and/or specialization. Altogether, the data suggest that duplicated r-protein genes undergo functional divergence into highly specialized paralogs and coexpression networks and that, similar to recent reports for yeast, these are likely actively involved in differentiation, development, and/or tissue-specific processes.
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Imai A, Komura M, Kawano E, Kuwashiro Y, Takahashi T. A semi-dominant mutation in the ribosomal protein L10 gene suppresses the dwarf phenotype of the acl5 mutant in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2008; 56:881-90. [PMID: 18694459 DOI: 10.1111/j.1365-313x.2008.03647.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Disruption of the Arabidopsis thaliana ACAULIS5 (ACL5) gene, which has recently been shown to encode thermospermine synthase, results in a severe dwarf phenotype. A previous study showed that sac51-d, a dominant suppressor mutant of acl5-1, has a premature termination codon in an upstream open reading frame (ORF) of SAC51, which encodes a putative transcription factor, and suggested the involvement of upstream ORF-mediated translational control in ACL5-dependent stem elongation. Here we report the identification of a gene responsible for sac52-d, another semi-dominant suppressor mutant of acl5-1. SAC52 encodes ribosomal protein L10 (RPL10A), which is highly conserved among eukaryotes and implicated in translational regulation. Transformation of acl5-1 mutants with a genomic fragment containing the sac52-d allele rescued the dwarf phenotype of acl5-1. GUS reporter activity under the control of a SAC51 promoter with its upstream ORF was higher in acl5-1 sac52-d than in acl5-1, suggesting that suppression of the acl5-1 phenotype by sac52-d is attributable, in part, to enhanced translation of certain transcripts including SAC51. We also found that a T-DNA insertion allele of SAC52/RPL10A causes lethality in the female gametophyte.
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Affiliation(s)
- Akihiro Imai
- Division of Bioscience, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
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Abstract
Plants, restricted by their environment, need to integrate a wide variety of stimuli with their metabolic activity, growth and development. Sugars, generated by photosynthetic carbon fixation, are central in coordinating metabolic fluxes in response to the changing environment and in providing cells and tissues with the necessary energy for continued growth and survival. A complex network of metabolic and hormone signaling pathways are intimately linked to diverse sugar responses. A combination of genetic, cellular and systems analyses have uncovered nuclear HXK1 (hexokinase1) as a pivotal and conserved glucose sensor, directly mediating transcription regulation, while the KIN10/11 energy sensor protein kinases function as master regulators of transcription networks under sugar and energy deprivation conditions. The involvement of disaccharide signals in the regulation of specific cellular processes and the potential role of cell surface receptors in mediating sugar signals add to the complexity. This chapter gives an overview of our current insight in the sugar sensing and signaling network and describes some of the molecular mechanisms involved.
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Affiliation(s)
- Matthew Ramon
- Department of Molecular Biology, Massachusetts General Hospital, Department of Genetics, Harvard Medical School, Boston, Massachusetts 02114
| | - Filip Rolland
- Department of Biology, Institute of Botany and Microbiology, K.U. Leuven, Kasteelpark Arenberg 31, 3001, Heverlee, Belgium
| | - Jen Sheen
- Department of Molecular Biology, Massachusetts General Hospital, Department of Genetics, Harvard Medical School, Boston, Massachusetts 02114
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Spencer MWB, Casson SA, Lindsey K. Transcriptional profiling of the Arabidopsis embryo. PLANT PHYSIOLOGY 2007; 143:924-40. [PMID: 17189330 PMCID: PMC1803724 DOI: 10.1104/pp.106.087668] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We have used laser-capture microdissection to isolate RNA from discrete tissues of globular, heart, and torpedo stage embryos of Arabidopsis (Arabidopsis thaliana). This was amplified and analyzed by DNA microarray using the Affymetrix ATH1 GeneChip, representing approximately 22,800 Arabidopsis genes. Cluster analysis showed that spatial differences in gene expression were less significant than temporal differences. Time course analysis reveals the dynamics and complexity of gene expression in both apical and basal domains of the developing embryo, with several classes of synexpressed genes identifiable. The transition from globular to heart stage is associated in particular with an up-regulation of genes involved in cell cycle control, transcriptional regulation, and energetics and metabolism. The transition from heart to torpedo stage is associated with a repression of cell cycle genes and an up-regulation of genes encoding storage proteins, and pathways of cell growth, energy, and metabolism. The torpedo stage embryo shows strong functional differentiation in the root and cotyledon, as inferred from the classes of genes expressed in these tissues. The time course of expression of the essential EMBRYO-DEFECTIVE genes shows that most are expressed at unchanging levels across all stages of embryogenesis. We show how identified genes can be used to generate cell type-specific markers and promoter activities for future application in cell biology.
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Affiliation(s)
- Matthew W B Spencer
- Integrative Cell Biology Laboratory, School of Biological and Biomedical Sciences, Durham University, Durham DH1 3LE, United Kingdom
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Rolland F, Baena-Gonzalez E, Sheen J. Sugar sensing and signaling in plants: conserved and novel mechanisms. ANNUAL REVIEW OF PLANT BIOLOGY 2006; 57:675-709. [PMID: 16669778 DOI: 10.1146/annurev.arplant.57.032905.105441] [Citation(s) in RCA: 1262] [Impact Index Per Article: 70.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Sugars not only fuel cellular carbon and energy metabolism but also play pivotal roles as signaling molecules. The experimental amenability of yeast as a unicellular model system has enabled the discovery of multiple sugar sensors and signaling pathways. In plants, different sugar signals are generated by photosynthesis and carbon metabolism in source and sink tissues to modulate growth, development, and stress responses. Genetic analyses have revealed extensive interactions between sugar and plant hormone signaling, and a central role for hexokinase (HXK) as a conserved glucose sensor. Diverse sugar signals activate multiple HXK-dependent and HXK-independent pathways and use different molecular mechanisms to control transcription, translation, protein stability and enzymatic activity. Important and complex roles for Snf1-related kinases (SnRKs), extracellular sugar sensors, and trehalose metabolism in plant sugar signaling are now also emerging.
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Affiliation(s)
- Filip Rolland
- Department of Molecular Microbiology, Flanders Interuniversity Institute for Biotechnology (VIB10), and Laboratory of Molecular Cell Biology K.U. Leuven, 3001 Heverlee-Leuven, Belgium.
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31
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Gibson SI. Control of plant development and gene expression by sugar signaling. CURRENT OPINION IN PLANT BIOLOGY 2005; 8:93-102. [PMID: 15653406 DOI: 10.1016/j.pbi.2004.11.003] [Citation(s) in RCA: 339] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Coordination of development with the availability of nutrients, such as soluble sugars, may help ensure an adequate supply of building materials and energy with which to carry out specific developmental programs. For example, in-vivo and in-vitro experiments suggest that increasing sugar levels delay seed germination and stimulate the induction of flowering and senescence in at least some plant species. Higher sugar concentrations can also increase the number of tubers formed by potatoes and can stimulate the formation of adventitious roots by Arabidopsis. New insights into the mechanisms by which sugar-response pathways interact with other response pathways have been provided by microarray experiments examining sugar-regulated gene expression under different light and nitrogen conditions.
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Affiliation(s)
- Susan I Gibson
- Department of Plant Biology, University of Minnesota, 122 Cargill Building, 1500 Gortner Avenue, St. Paul, Minnesota 55108-1095, USA.
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