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Miloro F, Kis A, Havelda Z, Dalmadi Á. Barley AGO4 proteins show overlapping functionality with distinct small RNA-binding properties in heterologous complementation. Plant Cell Rep 2024; 43:96. [PMID: 38480545 PMCID: PMC10937801 DOI: 10.1007/s00299-024-03177-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 02/15/2024] [Indexed: 03/17/2024]
Abstract
KEY MESSAGE Barley AGO4 proteins complement expressional changes of epigenetically regulated genes in Arabidopsis ago4-3 mutant and show a distinct affinity for the 5' terminal nucleotide of small RNAs, demonstrating functional conservation and divergence. The function of Argonaute 4 (AGO4) in Arabidopsis thaliana has been extensively characterized; however, its role in monocots, which have large genomes abundantly supplemented with transposable elements (TEs), remains elusive. The study of barley AGO4 proteins can provide insights into the conserved aspects of RNA-directed DNA methylation (RdDM) and could also have further applications in the field of epigenetics or crop improvement. Bioinformatic analysis of RNA sequencing data identified two active AGO4 genes in barley, HvAGO4a and HvAGO4b. These genes function similar to AtAGO4 in an Arabidopsis heterologous complementation system, primarily binding to 24-nucleotide long small RNAs (sRNAs) and triggering methylation at specific target loci. Like AtAGO4, HvAGO4B exhibits a preference for binding sRNAs with 5' adenine residue, while also accepting 5' guanine, uracil, and cytosine residues. In contrast, HvAGO4A selectively binds only sRNAs with a 5' adenine residue. The diverse binding capacity of barley AGO4 proteins is reflected in TE-derived sRNAs and in their varying abundance. Both barley AGO4 proteins effectively restore the levels of extrachromosomal DNA and transcript abundancy of the heat-activated ONSEN retrotransposon to those observed in wild-type Arabidopsis plants. Our study provides insight into the distinct binding specificities and involvement in TE regulation of barley AGO4 proteins in Arabidopsis by heterologous complementation.
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Affiliation(s)
- Fabio Miloro
- Hungarian University of Agriculture and Life Sciences (MATE), Institute of Genetics and Biotechnology, Gödöllő, Hungary
- Agribiotechnology and Precision Breeding for Food Security National Laboratory, Plant Biotechnology Section, Gödöllő, Hungary
| | - András Kis
- Hungarian University of Agriculture and Life Sciences (MATE), Institute of Genetics and Biotechnology, Gödöllő, Hungary
| | - Zoltán Havelda
- Hungarian University of Agriculture and Life Sciences (MATE), Institute of Genetics and Biotechnology, Gödöllő, Hungary
- Agribiotechnology and Precision Breeding for Food Security National Laboratory, Plant Biotechnology Section, Gödöllő, Hungary
| | - Ágnes Dalmadi
- Hungarian University of Agriculture and Life Sciences (MATE), Institute of Genetics and Biotechnology, Gödöllő, Hungary.
- Agribiotechnology and Precision Breeding for Food Security National Laboratory, Plant Biotechnology Section, Gödöllő, Hungary.
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Corrêa RL, Kutnjak D, Ambrós S, Bustos M, Elena SF. Identification of epigenetically regulated genes involved in plant-virus interaction and their role in virus-triggered induced resistance. BMC Plant Biol 2024; 24:172. [PMID: 38443837 PMCID: PMC10913459 DOI: 10.1186/s12870-024-04866-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 02/26/2024] [Indexed: 03/07/2024]
Abstract
BACKGROUND Plant responses to a wide range of stresses are known to be regulated by epigenetic mechanisms. Pathogen-related investigations, particularly against RNA viruses, are however scarce. It has been demonstrated that Arabidopsis thaliana plants defective in some members of the RNA-directed DNA methylation (RdDM) or histone modification pathways presented differential susceptibility to the turnip mosaic virus. In order to identify genes directly targeted by the RdDM-related RNA Polymerase V (POLV) complex and the histone demethylase protein JUMONJI14 (JMJ14) during infection, the transcriptomes of infected mutant and control plants were obtained and integrated with available chromatin occupancy data for various epigenetic proteins and marks. RESULTS A comprehensive list of virus-responsive gene candidates to be regulated by the two proteins was obtained. Twelve genes were selected for further characterization, confirming their dynamic regulation during the course of infection. Several epigenetic marks on their promoter sequences were found using in silico data, raising confidence that the identified genes are actually regulated by epigenetic mechanisms. The altered expression of six of these genes in mutants of the methyltransferase gene CURLY LEAF and the histone deacetylase gene HISTONE DEACETYLASE 19 suggests that some virus-responsive genes may be regulated by multiple coordinated epigenetic complexes. A temporally separated multiple plant virus infection experiment in which plants were transiently infected with one virus and then infected by a second one was designed to investigate the possible roles of the identified POLV- and JMJ14-regulated genes in wild-type (WT) plants. Plants that had previously been stimulated with viruses were found to be more resistant to subsequent virus challenge than control plants. Several POLV- and JMJ14-regulated genes were found to be regulated in virus induced resistance in WT plants, with some of them poisoned to be expressed in early infection stages. CONCLUSIONS A set of confident candidate genes directly regulated by the POLV and JMJ14 proteins during virus infection was identified, with indications that some of them may be regulated by multiple epigenetic modules. A subset of these genes may also play a role in the tolerance of WT plants to repeated, intermittent virus infections.
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Affiliation(s)
- Régis L Corrêa
- Institute for Integrative Systems Biology (I2SysBio), Consejo Superior de Investigaciones Cientificas (CSIC) - Universitat de València (UV), Paterna, Valencia, 46980, Spain.
- Department of Genetics, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, 21941-590, Brazil.
| | - Denis Kutnjak
- Institute for Integrative Systems Biology (I2SysBio), Consejo Superior de Investigaciones Cientificas (CSIC) - Universitat de València (UV), Paterna, Valencia, 46980, Spain
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, 1000, Slovenia
| | - Silvia Ambrós
- Institute for Integrative Systems Biology (I2SysBio), Consejo Superior de Investigaciones Cientificas (CSIC) - Universitat de València (UV), Paterna, Valencia, 46980, Spain
| | - Mónica Bustos
- Institute for Integrative Systems Biology (I2SysBio), Consejo Superior de Investigaciones Cientificas (CSIC) - Universitat de València (UV), Paterna, Valencia, 46980, Spain
| | - Santiago F Elena
- Institute for Integrative Systems Biology (I2SysBio), Consejo Superior de Investigaciones Cientificas (CSIC) - Universitat de València (UV), Paterna, Valencia, 46980, Spain
- The Santa Fe Institute, Santa Fe, NM, 87501, USA
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Xie G, Du X, Hu H, Du J. Molecular mechanisms of the RNA polymerases in plant RNA-directed DNA methylation. Trends Biochem Sci 2024; 49:247-256. [PMID: 38072749 DOI: 10.1016/j.tibs.2023.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 11/16/2023] [Accepted: 11/21/2023] [Indexed: 03/10/2024]
Abstract
In plants, two atypical DNA-dependent RNA polymerases, RNA polymerase IV (Pol IV) and Pol V, and an RNA-DEPENDENT RNA POLYMERASE 2 (RDR2) together produce noncoding RNAs (ncRNAs) to guide the plant-specific RNA-directed DNA methylation (RdDM). Although both Pol IV and Pol V have evolved from the canonical Pol II, they have adapted to different roles in RdDM. The mechanisms of their adaptation are key to understanding plant DNA methylation and the divergent evolution of polymerases. In this review, we summarize insights that have emerged from recent structural studies of Pol IV, Pol V, and RDR2 and discuss their structural features critical for efficient ncRNA production in RdDM.
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Affiliation(s)
- Guohui Xie
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Science, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen 518055, China
| | - Xuan Du
- Department of Biochemistry and Molecular Biology, International Cancer Center, Shenzhen University Medical School, Shenzhen 518060, China
| | - Hongmiao Hu
- MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Jiamu Du
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Science, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen 518055, China; Institute for Biological Electron Microscopy, Southern University of Science and Technology, Shenzhen 518055, China.
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Luo B, Zhang Z, Li B, Zhang H, Ma J, Li J, Han Z, Zhang C, Zhang S, Yu T, Zhang G, Ma P, Lan Y, Zhang X, Liu D, Wu L, Gao D, Gao S, Su S, Zhang X, Gao S. Chromatin remodeling analysis reveals the RdDM pathway responds to low-phosphorus stress in maize. Plant J 2024; 117:33-52. [PMID: 37731059 DOI: 10.1111/tpj.16468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 08/28/2023] [Accepted: 09/06/2023] [Indexed: 09/22/2023]
Abstract
Chromatin in eukaryotes folds into a complex three-dimensional (3D) structure that is essential for controlling gene expression and cellular function and is dynamically regulated in biological processes. Studies on plant phosphorus signaling have concentrated on single genes and gene interactions. It is critical to expand the existing signaling pathway in terms of its 3D structure. In this study, low-Pi treatment led to greater chromatin volume. Furthermore, low-Pi stress increased the insulation score and the number of TAD-like domains, but the effects on the A/B compartment were not obvious. The methylation levels of target sites (hereafter as RdDM levels) peaked at specific TAD-like boundaries, whereas RdDM peak levels at conserved TAD-like boundaries shifted and decreased sharply. The distribution pattern of RdDM sites originating from the Helitron transposons matched that of genome-wide RdDM sites near TAD-like boundaries. RdDM pathway genes were upregulated in the middle or early stages and downregulated in the later stages under low-Pi conditions. The RdDM pathway mutant ddm1a showed increased tolerance to low-Pi stress, with shortened and thickened roots contributing to higher Pi uptake from the shallow soil layer. ChIP-seq results revealed that ZmDDM1A could bind to Pi- and root development-related genes. Strong associations were found between interacting genes in significantly different chromatin-interaction regions and root traits. These findings not only expand the mechanisms by which plants respond to low-Pi stress through the RdDM pathway but also offer a crucial framework for the analysis of biological issues using 3D genomics.
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Affiliation(s)
- Bowen Luo
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, 611130, Sichuan, China
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Ziqi Zhang
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Binyang Li
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Haiying Zhang
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Junchi Ma
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Jing Li
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Zheng Han
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Chong Zhang
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Shuhao Zhang
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Ting Yu
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Guidi Zhang
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Peng Ma
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
- Mianyang Academy of Agricultural Sciences, Mianyang, 621023, Sichuan, China
- Crop Characteristic Resources Creation and Utilization Key Laboratory of Sichuan Province, Mianyang, China
| | - Yuzhou Lan
- Department of Plant Breeding, The Swedish University of Agricultural Sciences, P.O. Box 190, SE-23422, Lomma, Sweden
| | - Xiao Zhang
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Dan Liu
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Ling Wu
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Duojiang Gao
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Shiqiang Gao
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
| | - Shunzong Su
- College of Resources, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Xuecai Zhang
- International Maize and Wheat Improvement Center, Texcoco, Mexico
| | - Shibin Gao
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, 611130, Sichuan, China
- Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130, Sichuan, China
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Fu K, Wu Q, Jiang N, Hu S, Ye H, Hu Y, Li L, Li T, Sun Z. Identification and Expressional Analysis of siRNAs Responsive to Fusarium graminearum Infection in Wheat. Int J Mol Sci 2023; 24:16005. [PMID: 37958988 PMCID: PMC10650599 DOI: 10.3390/ijms242116005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 10/24/2023] [Accepted: 10/27/2023] [Indexed: 11/15/2023] Open
Abstract
The outbreak of Fusarium head blight (FHB) poses a serious threat to wheat production as it leads to both significant yield losses and accumulation of several mycotoxins including deoxynivalenol (DON) in the grains, which are harmful to human and livestock. To date, hundreds of FHB-resistance-related quantitative trait loci (QTLs) have been reported, but only a few of them have been cloned and used for breeding. Small interfering RNAs (siRNA) have been reported in plants to mediate host defense against pathogens, but they have rarely been reported in wheat-FHB interaction. In order to identify the key siRNAs that can potentially be used in the improvement of resistance to FHB, siRNAs from the spikes of an FHB-resistant variety Sumai 3 and an FHB-susceptible variety of Chinese Spring (CS) were sequenced after F. graminearum infection and mock inoculation, respectively. The expression patterns of the siRNAs of interest were analyzed. A total of 4019 siRNAs of high-confidence were identified, with 131 being CS-specific, 309 Sumai 3-specific and 3071 being common in both varieties. More than 87% of these siRNAs were 24 nt in length. An overall down-regulation trend was found for siRNAs in the spikes of both varieties after being infected with F. graminearum. The expression patterns for Triticum aestivum Dicer-like 3 (TaDCL3) that synthesizes 24 nt siRNAs were validated by qRT-PCR, which were positively correlated with those of the siRNAs. A total of 85% of the differentially expressed genes putatively targeted by the siRNAs were significantly up-regulated after infection, showing a negative correlation with the overall down-regulated expression of siRNAs. Interestingly, the majority of the up-regulated genes are annotated as disease resistance. These results suggested that the inhibition of siRNA by F. graminearum up-regulated the disease resistance genes, which were putatively suppressed by siRNAs through RNA-directed DNA methylation (RdDM). Consequently, the resistant capability to F. graminearum infection was enhanced. This study provides novel clues for investigating the function of siRNA in wheat-F. graminearum interaction.
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Affiliation(s)
- Kai Fu
- Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genetics and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; (K.F.); (Q.W.); (N.J.); (S.H.); (H.Y.); (Y.H.); (L.L.); (T.L.)
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Qianhui Wu
- Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genetics and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; (K.F.); (Q.W.); (N.J.); (S.H.); (H.Y.); (Y.H.); (L.L.); (T.L.)
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Ning Jiang
- Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genetics and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; (K.F.); (Q.W.); (N.J.); (S.H.); (H.Y.); (Y.H.); (L.L.); (T.L.)
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Sijia Hu
- Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genetics and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; (K.F.); (Q.W.); (N.J.); (S.H.); (H.Y.); (Y.H.); (L.L.); (T.L.)
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Hongyan Ye
- Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genetics and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; (K.F.); (Q.W.); (N.J.); (S.H.); (H.Y.); (Y.H.); (L.L.); (T.L.)
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Yi Hu
- Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genetics and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; (K.F.); (Q.W.); (N.J.); (S.H.); (H.Y.); (Y.H.); (L.L.); (T.L.)
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Lei Li
- Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genetics and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; (K.F.); (Q.W.); (N.J.); (S.H.); (H.Y.); (Y.H.); (L.L.); (T.L.)
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Tao Li
- Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genetics and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; (K.F.); (Q.W.); (N.J.); (S.H.); (H.Y.); (Y.H.); (L.L.); (T.L.)
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Zhengxi Sun
- Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genetics and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; (K.F.); (Q.W.); (N.J.); (S.H.); (H.Y.); (Y.H.); (L.L.); (T.L.)
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
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Sečnik A, Štajner N, Radišek S, Kunej U, Križman M, Jakše J. Cytosine Methylation in Genomic DNA and Characterization of DNA Methylases and Demethylases and Their Expression Profiles in Viroid-Infected Hop Plants ( Humulus lupulus Var. 'Celeia'). Cells 2022; 11:cells11162592. [PMID: 36010668 PMCID: PMC9406385 DOI: 10.3390/cells11162592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/08/2022] [Accepted: 08/16/2022] [Indexed: 11/16/2022] Open
Abstract
Abiotic and biotic stresses can lead to changes in host DNA methylation, which in plants is also mediated by an RNA-directed DNA methylation mechanism. Infections with viroids have been shown to affect DNA methylation dynamics in different plant hosts. The aim of our research was to determine the content of 5-methylcytosine (5-mC) in genomic DNA at the whole genome level of hop plants (Humulus lupulus Var. 'Celeia') infected with different viroids and their combinations and to analyse the expression of the selected genes to improve our understanding of DNA methylation dynamics in plant-viroid systems. The adapted HPLC-UV method used proved to be suitable for this purpose, and thus we were able to estimate for the first time that the cytosine methylation level in viroid-free hop plants was 26.7%. Interestingly, the observed 5-mC level was the lowest in hop plants infected simultaneously with CBCVd, HLVd and HSVd (23.7%), whereas the highest level was observed in plants infected with HLVd (31.4%). In addition, we identified three DNA methylases and one DNA demethylase gene in the hop's draft genome. The RT-qPCR revealed upregulation of all newly identified genes in hop plants infected with all three viroids, while no altered expression was observed in any of the other hop plants tested, except for CBCVd-infected hop plants, in which one DNA methylase was also upregulated.
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Affiliation(s)
- Andrej Sečnik
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Nataša Štajner
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Sebastjan Radišek
- Plant Protection Department, Slovenian Institute of Hop Research and Brewing, 3310 Žalec, Slovenia
| | - Urban Kunej
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Mitja Križman
- Laboratory for Food Chemistry, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Jernej Jakše
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
- Correspondence: ; Tel.: +386-1-3203280
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Wu X, Chai M, Liu J, Jiang X, Yang Y, Guo Y, Li Y, Cheng X. Turnip mosaic virus manipulates DRM2 expression to regulate host CHH and CHG methylation for robust infection. Stress Biol 2022; 2:29. [PMID: 37676449 PMCID: PMC10441925 DOI: 10.1007/s44154-022-00052-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 07/12/2022] [Indexed: 09/08/2023]
Abstract
DNA methylation is an important epigenetic marker for the suppression of transposable elements (TEs) and the regulation of plant immunity. However, little is known how RNA viruses counter defense such antiviral machinery. In this study, the change of DNA methylation in turnip mosaic virus (TuMV)-infected cells was analyzed by whole genome bisulfite sequencing. Results showed that the total number of methylated sites of CHH and CHG increased in TuMV-infected cells, the majority of differentially methylated regions (DMRs) in the CHH and CHG contexts were associated with hypermethylation. Gene expression analysis showed that the expression of two methylases (DRM2 and CMT3) and three demethylases (ROS3, DML2, DML3) was significantly increased and decreased in TuMV-infected cells, respectively. Pathogenicity tests showed that the enhanced resistance to TuMV of the loss-of-function mutant of DRM2 is associated with unregulated expression of several defense-related genes. Finally, we found TuMV-encoded NIb, the viral RNA-dependent RNA polymerase, was able to induce the expression of DRM2. In conclusion, this study discovered that TuMV can modulate host DNA methylation by regulating the expression of DRM2 to promote virus infection.
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Affiliation(s)
- Xiaoyun Wu
- Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region of Chinese Education Ministry, College of Agriculture, Northeast Agricultural University, Harbin, 150030 Heilongjiang China
| | - Mengzhu Chai
- Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region of Chinese Education Ministry, College of Agriculture, Northeast Agricultural University, Harbin, 150030 Heilongjiang China
| | - Jiahui Liu
- Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region of Chinese Education Ministry, College of Agriculture, Northeast Agricultural University, Harbin, 150030 Heilongjiang China
| | - Xue Jiang
- Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region of Chinese Education Ministry, College of Agriculture, Northeast Agricultural University, Harbin, 150030 Heilongjiang China
| | - Yingshuai Yang
- Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region of Chinese Education Ministry, College of Agriculture, Northeast Agricultural University, Harbin, 150030 Heilongjiang China
| | - Yushuang Guo
- Key Laboratory of Molecular Genetics, Guizhou Academy of Tobacco Science, Guiyang, 550081 China
| | - Yong Li
- College of Life Science, Northeast Agricultural University, Harbin, 150030 Heilongjiang China
| | - Xiaofei Cheng
- Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region of Chinese Education Ministry, College of Agriculture, Northeast Agricultural University, Harbin, 150030 Heilongjiang China
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Chakraborty T, Trujillo JT, Kendall T, Mosher RA. A null allele of the pol IV second subunit impacts stature and reproductive development in Oryza sativa. Plant J 2022; 111:748-755. [PMID: 35635763 DOI: 10.1111/tpj.15848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
All eukaryotes possess three DNA-dependent RNA polymerases, Pols I-III, while land plants possess two additional polymerases, Pol IV and Pol V. Derived through duplication of Pol II subunits, Pol IV produces 24-nt short interfering RNAs that interact with Pol V transcripts to target de novo DNA methylation and silence transcription of transposons. Members of the grass family encode additional duplicated subunits of Pol IV and V, raising questions regarding the function of each paralog. In this study, we identify a null allele of the putative Pol IV second subunit, NRPD2, and demonstrate that NRPD2 is the sole subunit functioning with NRPD1 in small RNA production and CHH methylation in leaves. Homozygous nrpd2 mutants have neither gametophytic defects nor embryo lethality, although adult plants are dwarf and sterile.
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Affiliation(s)
- Tania Chakraborty
- School of Plant Sciences, University of Arizona, Tucson, Arizona, 85721, USA
| | - Joshua T Trujillo
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, 47907, USA
| | - Timmy Kendall
- School of Plant Sciences, University of Arizona, Tucson, Arizona, 85721, USA
| | - Rebecca A Mosher
- School of Plant Sciences, University of Arizona, Tucson, Arizona, 85721, USA
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9
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Park SY, Cho J, Jeong DH. Small regulatory RNAs in rice epigenetic regulation. Biochem Soc Trans 2022:BST20210336. [PMID: 35579290 DOI: 10.1042/BST20210336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 04/27/2022] [Accepted: 04/29/2022] [Indexed: 11/17/2022]
Abstract
Plant small RNAs (sRNAs) are short non-coding RNAs that are implicated in various regulatory processes involving post-transcriptional gene silencing and epigenetic gene regulation. In epigenetic regulation, sRNAs are primarily involved in RNA-directed DNA methylation (RdDM) pathways. sRNAs in the RdDM pathways play a role not only in the suppression of transposable element (TE) activity but also in gene expression regulation. Although the major components of the RdDM pathways have been well studied in Arabidopsis, recent studies have revealed that the RdDM pathways in rice have important biological functions in stress response and developmental processes. In this review, we summarize and discuss recent literature on sRNA-mediated epigenetic regulation in rice. First, we describe the RdDM mechanisms in plants. We then introduce recent discoveries on the biological roles of rice genes involved in the RdDM pathway and TE-derived sRNAs working at specific genomic loci for epigenetic control in rice.
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10
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Shi Y, Huang R, Zhang Y, Feng Q, Pan X, Wang L. RNA Interference Induces BRCA1 Gene Methylation and Increases the Radiosensitivity of Breast Cancer Cells. Cancer Biother Radiopharm 2022. [PMID: 35180362 DOI: 10.1089/cbr.2021.0346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Purpose: To investigate the relationship between breast cancer susceptibility gene-1 (BRCA1) gene methylation and the radiosensitivity of breast cancer. Materials and Methods: The authors studied three breast cancer cell lines: MDA-MB-435, MDA-MB-231, and MCF-7 cells. They constructed five short hairpin RNAs (shRNAs) and five small interfering RNAs to target selected promoter loci and initiate sequence-specific methylation in breast cancer cells. Pyrosequencing was used to analyze the state of DNA methylation. Quantitative real-time polymerase chain reaction was used to detect BRCA1 mRNA expression and RNA-directed DNA methylation (RdDM)-related gene expression. Western blotting was performed to analyze BRCA1 protein expression. Colony formation assays and γ-histone H2A foci formation assays were conducted to assess the surviving fraction (SF) and double-strand break (DSB) repair ability of cells after irradiation. Results: The authors constructed five strains of lentivirus vectors and five plasmid vectors targeting BRCA1 promoter region. In MDA-MB-435 cells, lentivirus-mediated RNA interference targeting Site 1 of BRCA1 increased the methylation levels of BRCA1 and reduced BRCA1 mRNA and protein expression. The SF and the ability to repair DNA DSBs were reduced in the combined LV-BRCA1RNAi-Site 1 infection and irradiation group. Conclusions: The authors' findings suggest that the shRNA suppressed the expression levels of the BRCA1 gene and reduced the SF and DNA repair ability of cells after irradiation through RdDM. In summary, the radiosensitivity of breast cancer cells may correlate with BRCA1 methylation. Advances in Knowledge: The authors first utilized a lentivirus-based shRNA-mediated specific-sequence DNA methylation of the BRCA1 gene mediated by RdDM.
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Affiliation(s)
- Yuebin Shi
- Department of Pathology, The First People's Hospital of Yunnan Province, Kunming, Yunnan, China
| | - Rui Huang
- Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yong Zhang
- Department of Radiation Oncology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Qiang Feng
- Department of Pathology, 920th Hospital of Joint Logistics Support Force of PLA, Kunming, Yunnan, China
| | - Xinyan Pan
- Department of Pathology, 920th Hospital of Joint Logistics Support Force of PLA, Kunming, Yunnan, China
| | - Li Wang
- Department of Pathology, The First People's Hospital of Yunnan Province, Kunming, Yunnan, China
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11
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Rebolledo-Prudencio OG, Estrada-Rivera M, Dautt-Castro M, Arteaga-Vazquez MA, Arenas-Huertero C, Rosendo-Vargas MM, Jin H, Casas-Flores S. The small RNA-mediated gene silencing machinery is required in Arabidopsis for stimulation of growth, systemic disease resistance, and suppression of the nitrile-specifier gene NSP4 by Trichoderma atroviride. Plant J 2022; 109:873-890. [PMID: 34807478 DOI: 10.1111/tpj.15599] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 11/09/2021] [Accepted: 11/15/2021] [Indexed: 06/13/2023]
Abstract
Trichoderma atroviride is a root-colonizing fungus that confers multiple benefits to plants. In plants, small RNA (sRNA)-mediated gene silencing (sRNA-MGS) plays pivotal roles in growth, development, and pathogen attack. Here, we explored the role of core components of Arabidopsis thaliana sRNA-MGS pathways during its interaction with Trichoderma. Upon interaction with Trichoderma, sRNA-MGS-related genes paralleled the expression of Arabidopsis defense-related genes, linked to salicylic acid (SA) and jasmonic acid (JA) pathways. SA- and JA-related genes were primed by Trichoderma in leaves after the application of the well-known pathogen-associated molecular patterns flg22 and chitin, respectively. Defense-related genes were primed in roots as well, but to different extents and behaviors. Phenotypical characterization of mutants in AGO genes and components of the RNA-dependent DNA methylation (RdDM) pathway revealed that different sets of sRNA-MGS-related genes are essential for (i) the induction of systemic acquired resistance against Botrytis cinerea, (ii) the activation of the expression of plant defense-related genes, and (iii) root colonization by Trichoderma. Additionally, plant growth induced by Trichoderma depends on functional RdDM. Profiling of DNA methylation and histone N-tail modification patterns at the Arabidopsis Nitrile-Specifier Protein-4 (NSP4) locus, which is responsive to Trichoderma, showed altered epigenetic modifications in RdDM mutants. Furthermore, NSP4 is required for the induction of systemic acquired resistance against Botrytis and avoidance of enhanced root colonization by Trichoderma. Together, our results indicate that RdDM is essential in Arabidopsis to establish a beneficial relationship with Trichoderma. We propose that DNA methylation and histone modifications are required for plant priming by the beneficial fungus against B. cinerea.
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Affiliation(s)
- Oscar Guillermo Rebolledo-Prudencio
- División de Biología Molecular, IPICYT, Camino a la presa San José No. 2055, Colonia Lomas 4ª Sección, San Luis Potosí, S.L.P., C.P. 78216, Mexico
| | - Magnolia Estrada-Rivera
- División de Biología Molecular, IPICYT, Camino a la presa San José No. 2055, Colonia Lomas 4ª Sección, San Luis Potosí, S.L.P., C.P. 78216, Mexico
| | - Mitzuko Dautt-Castro
- División de Biología Molecular, IPICYT, Camino a la presa San José No. 2055, Colonia Lomas 4ª Sección, San Luis Potosí, S.L.P., C.P. 78216, Mexico
| | - Mario A Arteaga-Vazquez
- Universidad Veracruzana, INBIOTECA-Instituto de Biotecnología y Ecología Aplicada, Av. de las Culturas Veracruzanas No. 101, Colonia Emiliano Zapata, Xalapa, Veracruz, C.P. 91090, Mexico
| | - Catalina Arenas-Huertero
- Facultad de Ciencias, Universidad Autónoma de San Luis Potosí, Av. Chapultepec #1570, Priv del Pedregal., San Luis Potosí, S.L.P., C.P. 78295, Mexico
| | - Maria Montserrat Rosendo-Vargas
- División de Biología Molecular, IPICYT, Camino a la presa San José No. 2055, Colonia Lomas 4ª Sección, San Luis Potosí, S.L.P., C.P. 78216, Mexico
| | - Hailing Jin
- Department of Plant Pathology and Microbiology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Sergio Casas-Flores
- División de Biología Molecular, IPICYT, Camino a la presa San José No. 2055, Colonia Lomas 4ª Sección, San Luis Potosí, S.L.P., C.P. 78216, Mexico
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12
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Loffer A, Singh J, Fukudome A, Mishra V, Wang F, Pikaard CS. A DCL3 dicing code within Pol IV-RDR2 transcripts diversifies the siRNA pool guiding RNA-directed DNA methylation. eLife 2022; 11:e73260. [PMID: 35098919 PMCID: PMC8846587 DOI: 10.7554/elife.73260] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 01/28/2022] [Indexed: 11/26/2022] Open
Abstract
In plants, selfish genetic elements, including retrotransposons and DNA viruses, are transcriptionally silenced by RNA-directed DNA methylation. Guiding the process are short interfering RNAs (siRNAs) cut by DICER-LIKE 3 (DCL3) from double-stranded precursors of ~30 bp that are synthesized by NUCLEAR RNA POLYMERASE IV (Pol IV) and RNA-DEPENDENT RNA POLYMERASE 2 (RDR2). We show that Pol IV's choice of initiating nucleotide, RDR2's initiation 1-2 nt internal to Pol IV transcript ends and RDR2's terminal transferase activity collectively yield a code that influences which precursor end is diced and whether 24 or 23 nt siRNAs are produced. By diversifying the size, sequence, and strand specificity of siRNAs derived from a given precursor, alternative patterns of DCL3 dicing allow for maximal siRNA coverage at methylated target loci.
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Affiliation(s)
- Andrew Loffer
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University BloomingtonBloomingtonUnited States
| | - Jasleen Singh
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University BloomingtonBloomingtonUnited States
| | - Akihito Fukudome
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University BloomingtonBloomingtonUnited States
- Howard Hughes Medical Institute, Indiana UniversityBloomingtonUnited States
| | - Vibhor Mishra
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University BloomingtonBloomingtonUnited States
- Howard Hughes Medical Institute, Indiana UniversityBloomingtonUnited States
| | - Feng Wang
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University BloomingtonBloomingtonUnited States
- Howard Hughes Medical Institute, Indiana UniversityBloomingtonUnited States
| | - Craig S Pikaard
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University BloomingtonBloomingtonUnited States
- Howard Hughes Medical Institute, Indiana UniversityBloomingtonUnited States
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13
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Takehira K, Hayashi Y, Nozawa K, Chen L, Suzuki T, Masuta Y, Kato A, Ito H. DRD1, a SWI/SNF-like chromatin remodeling protein, regulates a heat-activated transposon in Arabidopsis thaliana. Genes Genet Syst 2021; 96:151-158. [PMID: 34373369 DOI: 10.1266/ggs.21-00005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
ONSEN is a heat-activated LTR retrotransposon in Arabidopsis thaliana. Screens to identify transcriptional regulatory factors of ONSEN revealed a SWI/SNF-like chromatin remodeling protein, DRD1, which cooperates with plant-specific RNA polymerase and is involved in RNA-directed DNA methylation. ONSEN transcript level was increased in the drd1 mutant relative to wild-type under heat stress, indicating that DRD1 plays a significant role in the silencing of activated ONSEN under the stress condition. The transcript level of HsfA2, which is directly involved in transcriptional activation of ONSEN, was not higher in the drd1 mutant than in the wild-type. Interestingly, no transgenerational transposition of ONSEN was observed in the drd1 mutant, even though DNA methylation levels were significantly reduced and expression levels were increased compared to the wild-type. These results suggest that other factors are involved in the regulation of ONSEN transposition in addition to the transcript level of ONSEN.
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Affiliation(s)
| | - Yui Hayashi
- Graduate School of Life Science, Hokkaido University
| | - Kosuke Nozawa
- Graduate School of Life Science, Hokkaido University
| | - Lu Chen
- Graduate School of Life Science, Hokkaido University
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14
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Huang P, Huang H, Lin X, Liu P, Zhao L, Nie W, Zhu J, Lang Z. MSI4/FVE is required for accumulation of 24-nt siRNAs and DNA methylation at a subset of target regions of RNA-directed DNA methylation. Plant J 2021; 108:347-357. [PMID: 34314526 PMCID: PMC9292519 DOI: 10.1111/tpj.15441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 07/20/2021] [Indexed: 05/20/2023]
Abstract
DNA methylation is an important epigenetic mark. In plants, de novo DNA methylation occurs mainly through the RNA-directed DNA methylation (RdDM) pathway. Researchers have previously inferred that a flowering regulator, MULTICOPY SUPPRESSOR OF IRA1 4 (MSI4)/FVE, is involved in non-CG methylation at several RdDM targets, suggesting a role of FVE in RdDM. However, whether and how FVE affects RdDM genome-wide is not known. Here, we report that FVE is required for DNA methylation at thousands of RdDM target regions. In addition, dysfunction of FVE significantly reduces 24-nucleotide siRNA accumulation that is dependent on factors downstream in the RdDM pathway. By using chromatin immunoprecipitation and sequencing (ChIP-seq), we show that FVE directly binds to FVE-dependent 24-nucleotide siRNA cluster regions. Our results also indicate that FVE may function in RdDM by physically interacting with RDM15, a downstream factor in the RdDM pathway. Our study has therefore revealed that FVE, by associating with RDM15, directly regulates DNA methylation and siRNA accumulation at a subset of RdDM targets.
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Affiliation(s)
- Pei Huang
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
- University of Chinese Academy of SciencesNo.19 Yuquan Road, Shijingshan DistrictBeijing100049China
| | - Huan Huang
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
| | - Xueqiang Lin
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
| | - Pan Liu
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
| | - Lun Zhao
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
- National Key Laboratory of Crop Genetic ImprovementNational Center of Rapeseed ImprovementHuazhong Agricultural UniversityWuhan430070China
| | - Wen‐Feng Nie
- Department of HorticultureCollege of Horticulture and Plant ProtectionYangzhou UniversityYangzhouJiangsu225009China
| | - Jian‐Kang Zhu
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
| | - Zhaobo Lang
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
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15
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Madzima TF, Vendramin S, Lynn JS, Lemert P, Lu KC, McGinnis KM. Direct and Indirect Transcriptional Effects of Abiotic Stress in Zea mays Plants Defective in RNA-Directed DNA Methylation. Front Plant Sci 2021; 12:694289. [PMID: 34489998 PMCID: PMC8418275 DOI: 10.3389/fpls.2021.694289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 07/14/2021] [Indexed: 06/13/2023]
Abstract
Plants respond to abiotic stress stimuli, such as water deprivation, through a hierarchical cascade that includes detection and signaling to mediate transcriptional and physiological changes. The phytohormone abscisic acid (ABA) is well-characterized for its regulatory role in these processes in response to specific environmental cues. ABA-mediated changes in gene expression have been demonstrated to be temporally-dependent, however, the genome-wide timing of these responses are not well-characterized in the agronomically important crop plant Zea mays (maize). ABA-mediated responses are synergistic with other regulatory mechanisms, including the plant-specific RNA-directed DNA methylation (RdDM) epigenetic pathway. Our prior work demonstrated that after relatively long-term ABA induction (8 h), maize plants homozygous for the mop1-1 mutation, defective in a component of the RdDM pathway, exhibit enhanced transcriptional sensitivity to the phytohormone. At this time-point, many hierarchically positioned transcription factors are differentially expressed resulting in primary (direct) and secondary (indirect) transcriptional outcomes. To identify more immediate and direct MOP1-dependent responses to ABA, we conducted a transcriptomic analysis using mop1-1 mutant and wild type plants treated with ABA for 1 h. One h of ABA treatment was sufficient to induce unique categories of differentially expressed genes (DEGs) in mop1-1. A comparative analysis between the two time-points revealed that distinct epigenetically-regulated changes in gene expression occur within the early stages of ABA induction, and that these changes are predicted to influence less immediate, indirect transcriptional responses. Homology with MOP1-dependent siRNAs and a gene regulatory network (GRN) were used to identify putative immediate and indirect targets, respectively. By manipulating two key regulatory networks in a temporal dependent manner, we identified genes and biological processes regulated by RdDM and ABA-mediated stress responses. Consistent with mis-regulation of gene expression, mop1-1 homozygous plants are compromised in their ability to recover from water deprivation. Collectively, these results indicate transcriptionally and physiologically relevant roles for MOP1-mediated regulation of gene expression of plant responses to environmental stress.
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Affiliation(s)
- Thelma F. Madzima
- Division of Biological Sciences, School of STEM, University of Washington Bothell, Bothell, WA, United States
| | - Stefania Vendramin
- Department of Biological Science, Florida State University, Tallahassee, FL, United States
| | - Jason S. Lynn
- Department of Biological Science, Florida State University, Tallahassee, FL, United States
| | - Phebe Lemert
- Department of Biological Science, Florida State University, Tallahassee, FL, United States
| | - Katherine C. Lu
- Division of Biological Sciences, School of STEM, University of Washington Bothell, Bothell, WA, United States
| | - Karen M. McGinnis
- Department of Biological Science, Florida State University, Tallahassee, FL, United States
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16
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Abstract
Plants have an extraordinary diversity of transcription machineries, including five nuclear DNA-dependent RNA polymerases. Four of these enzymes are dedicated to the production of long noncoding RNAs (lncRNAs), which are ribonucleic acids with functions independent of their protein-coding potential. lncRNAs display a broad range of lengths and structures, but they are distinct from the small RNA guides of RNA interference (RNAi) pathways. lncRNAs frequently serve as structural, catalytic, or regulatory molecules for gene expression. They can affect all elements of genes, including promoters, untranslated regions, exons, introns, and terminators, controlling gene expression at various levels, including modifying chromatin accessibility, transcription, splicing, and translation. Certain lncRNAs protect genome integrity, while others respond to environmental cues like temperature, drought, nutrients, and pathogens. In this review, we explain the challenge of defining lncRNAs, introduce the machineries responsible for their production, and organize this knowledge by viewing the functions of lncRNAs throughout the structure of a typical plant gene.
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Affiliation(s)
- Andrzej T Wierzbicki
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109, USA;
| | - Todd Blevins
- Institut de Biologie Moléculaire des Plantes, CNRS, Université de Strasbourg, F-67084 Strasbourg, France;
| | - Szymon Swiezewski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland;
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17
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Wang Y, Zhou X, Luo J, Lv S, Liu R, Du X, Jia B, Yuan F, Zhang H, Du J. Recognition of H3K9me1 by maize RNA-directed DNA methylation factor SHH2. J Integr Plant Biol 2021; 63:1091-1096. [PMID: 33913587 DOI: 10.1111/jipb.13103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 04/20/2021] [Indexed: 06/12/2023]
Abstract
RNA-directed DNA methylation (RdDM) is a plant-specific de novo DNA methylation pathway, which has extensive cross-talk with histone modifications. Here, we report that the maize RdDM regulator SAWADEE HOMEODOMAIN HOMOLOG 2 (SHH2) is an H3K9me1 reader. Our structural studies reveal that H3K9me1 recognition is achieved by recognition of the methyl group via a classic aromatic cage and hydrogen-bonding and salt-bridge interactions with the free protons of the mono-methyllysine. The di- and tri-methylation states disrupt the polar interactions, decreasing the binding affinity. Our study reveals a mono-methyllysine recognition mechanism which potentially links RdDM to H3K9me1 in maize.
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Affiliation(s)
- Yuhua Wang
- National Key Laboratory of Plant Molecular Genetics and Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, The Chinese Academy of Sciences, Shanghai, 201602, China
| | - Xuelin Zhou
- National Key Laboratory of Plant Molecular Genetics and Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, The Chinese Academy of Sciences, Shanghai, 201602, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jinyan Luo
- National Key Laboratory of Plant Molecular Genetics and Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, The Chinese Academy of Sciences, Shanghai, 201602, China
| | - Suhui Lv
- School of Life Science, Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Science, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Rui Liu
- School of Life Science, Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Science, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Xuan Du
- School of Life Science, Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Science, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Bei Jia
- National Key Laboratory of Plant Molecular Genetics and Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, The Chinese Academy of Sciences, Shanghai, 201602, China
| | - Fengtong Yuan
- National Key Laboratory of Plant Molecular Genetics and Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, The Chinese Academy of Sciences, Shanghai, 201602, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Heng Zhang
- National Key Laboratory of Plant Molecular Genetics and Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, The Chinese Academy of Sciences, Shanghai, 201602, China
| | - Jiamu Du
- School of Life Science, Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Science, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China
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18
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Wassenegger M, Dalakouras A. Viroids as a Tool to Study RNA-Directed DNA Methylation in Plants. Cells 2021; 10:1187. [PMID: 34067940 DOI: 10.3390/cells10051187] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/10/2021] [Accepted: 05/10/2021] [Indexed: 12/11/2022] Open
Abstract
Viroids are plant pathogenic, circular, non-coding, single-stranded RNAs (ssRNAs). Members of the Pospiviroidae family replicate in the nucleus of plant cells through double-stranded RNA (dsRNA) intermediates, thus triggering the host’s RNA interference (RNAi) machinery. In plants, the two RNAi pillars are Post-Transcriptional Gene Silencing (PTGS) and RNA-directed DNA Methylation (RdDM), and the latter has the potential to trigger Transcriptional Gene Silencing (TGS). Over the last three decades, the employment of viroid-based systems has immensely contributed to our understanding of both of these RNAi facets. In this review, we highlight the role of Pospiviroidae in the discovery of RdDM, expound the gradual elucidation through the years of the diverse array of RdDM’s mechanistic details and propose a revised RdDM model based on the cumulative amount of evidence from viroid and non-viroid systems.
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19
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Chakraborty T, Kendall T, Grover JW, Mosher RA. Embryo CHH hypermethylation is mediated by RdDM and is autonomously directed in Brassica rapa. Genome Biol 2021; 22:140. [PMID: 33957938 PMCID: PMC8101221 DOI: 10.1186/s13059-021-02358-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 04/21/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND RNA-directed DNA methylation (RdDM) initiates cytosine methylation in all contexts and maintains asymmetric CHH methylation. Mature plant embryos show one of the highest levels of CHH methylation, and it has been suggested that RdDM is responsible for this hypermethylation. Because loss of RdDM in Brassica rapa causes seed abortion, embryo methylation might play a role in seed development. RdDM is required in the maternal sporophyte, suggesting that small RNAs from the maternal sporophyte might translocate to the developing embryo, triggering DNA methylation that prevents seed abortion. This raises the question of whether embryo hypermethylation is autonomously regulated by the embryo itself or influenced by the maternal sporophyte. RESULTS Here, we demonstrate that B. rapa embryos are hypermethylated in both euchromatin and heterochromatin and that this process requires RdDM. Contrary to the current models, B. rapa embryo hypermethylation is not correlated with demethylation of the endosperm. We also show that maternal somatic RdDM is not sufficient for global embryo hypermethylation, and we find no compelling evidence for maternal somatic influence over embryo methylation at any locus. Decoupling of maternal and zygotic RdDM leads to successful seed development despite the loss of embryo CHH hypermethylation. CONCLUSIONS We conclude that embryo CHH hypermethylation is conserved, autonomously controlled, and not required for embryo development. Furthermore, maternal somatic RdDM, while required for seed development, does not directly influence embryo methylation patterns.
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Affiliation(s)
- Tania Chakraborty
- The School of Plant Sciences, The University of Arizona, Tucson, AZ 85721 USA
| | - Timmy Kendall
- The School of Plant Sciences, The University of Arizona, Tucson, AZ 85721 USA
| | - Jeffrey W. Grover
- Department of Molecular and Cellular Biology, The University of Arizona, Tucson, AZ 85721 USA
| | - Rebecca A. Mosher
- The School of Plant Sciences, The University of Arizona, Tucson, AZ 85721 USA
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20
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Mishra V, Singh J, Wang F, Zhang Y, Fukudome A, Trinidad JC, Takagi Y, Pikaard CS. Assembly of a dsRNA synthesizing complex: RNA-DEPENDENT RNA POLYMERASE 2 contacts the largest subunit of NUCLEAR RNA POLYMERASE IV. Proc Natl Acad Sci U S A 2021; 118:e2019276118. [PMID: 33753485 DOI: 10.1073/pnas.2019276118] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Short interfering RNAs (siRNAs) can inhibit mRNA translation or guide chromatin modifications that inhibit transcription, thus impacting gene regulation. In plants, transcriptional gene silencing involves siRNAs whose double-stranded (ds) precursors are generated by the coupled activities of NUCLEAR RNA POLYMERASE IV and RNA-DEPENDENT RNA POLYMERASE 2. We present evidence that Pol IV-RDR2 association involves contact between RDR2 and NRPD1, Pol IV’s largest catalytic subunit. As the only subunit never shared by Pol II or Pol IV, NRPD1 interaction accounts for RDR2's specific association with Pol IV. The positions of the protein docking sites suggest that Pol IV transcripts are generated in close proximity to RDR2’s catalytic site, enabling RDR2 to efficiently engage Pol IV transcripts and convert them into dsRNAs. In plants, transcription of selfish genetic elements such as transposons and DNA viruses is suppressed by RNA-directed DNA methylation. This process is guided by 24-nt short-interfering RNAs (siRNAs) whose double-stranded precursors are synthesized by DNA-dependent NUCLEAR RNA POLYMERASE IV (Pol IV) and RNA-DEPENDENT RNA POLYMERASE 2 (RDR2). Pol IV and RDR2 coimmunoprecipitate, and their activities are tightly coupled, yet the basis for their association is unknown. Here, we show that an interval near the RDR2 active site contacts the Pol IV catalytic subunit, NRPD1, the largest of Pol IV’s 12 subunits. Contacts between the catalytic regions of the two enzymes suggests that RDR2 is positioned to rapidly engage the free 3′ ends of Pol IV transcripts and convert these single-stranded transcripts into double-stranded RNAs (dsRNAs).
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21
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Kaushal R, Peng L, Singh SK, Zhang M, Zhang X, Vílchez JI, Wang Z, He D, Yang Y, Lv S, Xu Z, Morcillo RJL, Wang W, Huang W, Paré PW, Song CP, Zhu JK, Liu R, Zhong W, Ma P, Zhang H. Dicer-like proteins influence Arabidopsis root microbiota independent of RNA-directed DNA methylation. Microbiome 2021; 9:57. [PMID: 33637135 PMCID: PMC7913254 DOI: 10.1186/s40168-020-00966-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 12/06/2020] [Indexed: 05/20/2023]
Abstract
BACKGROUND Plants are naturally associated with root microbiota, which are microbial communities influential to host fitness. Thus, it is important to understand how plants control root microbiota. Epigenetic factors regulate the readouts of genetic information and consequently many essential biological processes. However, it has been elusive whether RNA-directed DNA methylation (RdDM) affects root microbiota assembly. RESULTS By applying 16S rRNA gene sequencing, we investigated root microbiota of Arabidopsis mutants defective in the canonical RdDM pathway, including dcl234 that harbors triple mutation in the Dicer-like proteins DCL3, DCL2, and DCL4, which produce small RNAs for RdDM. Alpha diversity analysis showed reductions in microbe richness from the soil to roots, reflecting the selectivity of plants on root-associated bacteria. The dcl234 triple mutation significantly decreases the levels of Aeromonadaceae and Pseudomonadaceae, while it increases the abundance of many other bacteria families in the root microbiota. However, mutants of the other examined key players in the canonical RdDM pathway showed similar microbiota as Col-0, indicating that the DCL proteins affect root microbiota in an RdDM-independent manner. Subsequently gene analysis by shotgun sequencing of root microbiome indicated a selective pressure on microbial resistance to plant defense in the dcl234 mutant. Consistent with the altered plant-microbe interactions, dcl234 displayed altered characters, including the mRNA and sRNA transcriptomes that jointly highlighted altered cell wall organization and up-regulated defense, the decreased cellulose and callose deposition in root xylem, and the restructured profile of root exudates that supported the alterations in gene expression and cell wall modifications. CONCLUSION Our findings demonstrate an important role of the DCL proteins in influencing root microbiota through integrated regulation of plant defense, cell wall compositions, and root exudates. Our results also demonstrate that the canonical RdDM is dispensable for Arabidopsis root microbiota. These findings not only establish a connection between root microbiota and plant epigenetic factors but also highlight the complexity of plant regulation of root microbiota. Video abstract.
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Affiliation(s)
- Richa Kaushal
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602 China
| | - Li Peng
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602 China
| | - Sunil K. Singh
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602 China
| | - Mengrui Zhang
- Department of Statistics, University of Georgia, Athens, GA 30602 USA
| | - Xinlian Zhang
- Department of Statistics, University of Georgia, Athens, GA 30602 USA
| | - Juan I. Vílchez
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602 China
| | - Zhen Wang
- Department of Statistics, University of Georgia, Athens, GA 30602 USA
| | - Danxia He
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Yu Yang
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602 China
| | - Suhui Lv
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Zhongtian Xu
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602 China
- Current address: Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
| | - Rafael J. L. Morcillo
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602 China
- Current address: Institute for Water Research and Department of Microbiology, University of Granada, Granada, Spain
| | - Wei Wang
- Shanghai Chenshan Botanical Garden, Shanghai, 201602 China
| | - Weichang Huang
- Shanghai Chenshan Botanical Garden, Shanghai, 201602 China
| | - Paul W. Paré
- Department of Chemistry & Biochemistry, Texas Tech University, Lubbock, TX 79409 USA
| | - Chun-Peng Song
- State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng, 475004 China
| | - Jian-Kang Zhu
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602 China
- Department of Horticulture & Landscape Architecture, Purdue University, West Lafayette, IN 47906 USA
| | - Renyi Liu
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602 China
- Current address: Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
| | - Wenxuan Zhong
- Department of Statistics, University of Georgia, Athens, GA 30602 USA
| | - Ping Ma
- Department of Statistics, University of Georgia, Athens, GA 30602 USA
| | - Huiming Zhang
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602 China
- State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng, 475004 China
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22
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Palomar VM, Garciarrubio A, Garay-Arroyo A, Martínez-Martínez C, Rosas-Bringas O, Reyes JL, Covarrubias AA. The canonical RdDM pathway mediates the control of seed germination timing under salinity. Plant J 2021; 105:691-707. [PMID: 33131171 DOI: 10.1111/tpj.15064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 09/11/2020] [Accepted: 10/26/2020] [Indexed: 06/11/2023]
Abstract
Plants respond to adverse environmental cues by adjusting a wide variety of processes through highly regulated mechanisms to maintain plant homeostasis for survival. As a result of the sessile nature of plants, their response, adjustment and adaptation to the changing environment is intimately coordinated with their developmental programs through the crosstalk of regulatory networks. Germination is a critical process in the plant life cycle, and thus plants have evolved various strategies to control the timing of germination according to their local environment. The mechanisms involved in these adjustment responses are largely unknown, however. Here, we report that mutations in core elements of canonical RNA-directed DNA methylation (RdDM) affect the germination and post-germination growth of Arabidopsis seeds grown under salinity stress. Transcriptomic and whole-genome bisulfite sequencing (WGBS) analyses support the involvement of this pathway in the control of germination timing and post-germination growth under salinity stress by preventing the transcriptional activation of genes implicated in these processes. Subsequent transcriptional effects on genes that function in relation to these developmental events support this conclusion.
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Affiliation(s)
- Víctor Miguel Palomar
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, Mor. C.P, 62250, Mexico
| | - Alejandro Garciarrubio
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, Mor. C.P, 62250, Mexico
| | - Adriana Garay-Arroyo
- Laboratorio de Genética Molecular, Desarrollo y Evolución de Plantas, Instituto de Ecología, Universidad Nacional Autónoma de México, Circuito Exterior S/N anexo Jardín Botánico Exterior, Ciudad Universitaria, Ciudad de México, C.P. 04500, México
| | - Coral Martínez-Martínez
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, Mor. C.P, 62250, Mexico
| | - Omar Rosas-Bringas
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, Mor. C.P, 62250, Mexico
| | - José L Reyes
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, Mor. C.P, 62250, Mexico
| | - Alejandra A Covarrubias
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, Mor. C.P, 62250, Mexico
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23
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Ghosh A, Igamberdiev AU, Debnath SC. Tissue culture-induced DNA methylation in crop plants: a review. Mol Biol Rep 2021; 48:823-41. [PMID: 33394224 DOI: 10.1007/s11033-020-06062-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 12/03/2020] [Indexed: 12/15/2022]
Abstract
Plant tissue culture techniques have been extensively employed in commercial micropropagation to provide year-round production. Tissue culture regenerants are not always genotypically and phenotypically similar. Due to the changes in the tissue culture microenvironment, plant cells are exposed to additional stress which induces genetic and epigenetic instabilities in the regenerants. These changes lead to tissue culture-induced variations (TCIV) which are also known as somaclonal variations to categorically specify the inducing environment. TCIV includes molecular and phenotypic changes persuaded in the in vitro culture due to continuous sub-culturing and tissue culture-derived stress. Epigenetic variations such as altered DNA methylation pattern are induced due to the above-mentioned factors. Reportedly, alteration in DNA methylation pattern is much more frequent in the plant genome during the tissue culture process. DNA methylation plays an important role in gene expression and regulation of plant development. Variants originated in tissue culture process due to heritable methylation changes, can contribute to intra-species phenotypic variation. Several molecular techniques are available to detect DNA methylation at different stages of in vitro culture. Here, we review the aspects of TCIV with respect to DNA methylation and its effect on crop improvement programs. It is anticipated that a precise and comprehensive knowledge of molecular basis of in vitro-derived DNA methylation will help to design strategies to overcome the bottlenecks of micropropagation system and maintain the clonal fidelity of the regenerants.
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24
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Abstract
We discuss the latest findings on RNA polymerase IV (Pol IV) in plant growth and development, providing new insights and expanding on new ideas for further, more in-depth research on Pol IV.
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Affiliation(s)
- Shuai Zhang
- Vector-borne Virus Research Center, State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Province Key Laboratory of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xiao-Qing Wu
- Vector-borne Virus Research Center, State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Province Key Laboratory of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Hui-Ting Xie
- Vector-borne Virus Research Center, State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Province Key Laboratory of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Shan-Shan Zhao
- Vector-borne Virus Research Center, State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Province Key Laboratory of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Jian-Guo Wu
- Vector-borne Virus Research Center, State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Province Key Laboratory of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, China
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25
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Gallego-Bartolomé J. DNA methylation in plants: mechanisms and tools for targeted manipulation. New Phytol 2020; 227:38-44. [PMID: 32159848 DOI: 10.1111/nph.16529] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 02/19/2020] [Indexed: 05/23/2023]
Abstract
DNA methylation is an epigenetic mark that regulates multiple processes, such as gene expression and genome stability. Mutants and pharmacological treatments have been instrumental in the study of this mark in plants, although their genome-wide effect complicates the direct association between changes in methylation and a particular phenotype. A variety of tools that allow locus-specific manipulation of DNA methylation can be used to assess its direct role in specific processes, as well as to create novel epialleles. Recently, new tools that recruit the methylation machinery directly to target loci through programmable DNA-binding proteins have expanded the tool kit available to researchers. This review provides an overview of DNA methylation in plants and discusses the tools that have recently been developed for its manipulation.
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Affiliation(s)
- Javier Gallego-Bartolomé
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universidad Politécnica de Valencia, 46011, Valencia, Spain
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26
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Grover JW, Burgess D, Kendall T, Baten A, Pokhrel S, King GJ, Meyers BC, Freeling M, Mosher RA. Abundant expression of maternal siRNAs is a conserved feature of seed development. Proc Natl Acad Sci U S A 2020; 117:15305-15. [PMID: 32541052 DOI: 10.1073/pnas.2001332117] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Small RNAs are abundant in plant reproductive tissues, especially 24-nucleotide (nt) small interfering RNAs (siRNAs). Most 24-nt siRNAs are dependent on RNA Pol IV and RNA-DEPENDENT RNA POLYMERASE 2 (RDR2) and establish DNA methylation at thousands of genomic loci in a process called RNA-directed DNA methylation (RdDM). In Brassica rapa, RdDM is required in the maternal sporophyte for successful seed development. Here, we demonstrate that a small number of siRNA loci account for over 90% of siRNA expression during B. rapa seed development. These loci exhibit unique characteristics with regard to their copy number and association with genomic features, but they resemble canonical 24-nt siRNA loci in their dependence on RNA Pol IV/RDR2 and role in RdDM. These loci are expressed in ovules before fertilization and in the seed coat, embryo, and endosperm following fertilization. We observed a similar pattern of 24-nt siRNA expression in diverse angiosperms despite rapid sequence evolution at siren loci. In the endosperm, siren siRNAs show a marked maternal bias, and siren expression in maternal sporophytic tissues is required for siren siRNA accumulation. Together, these results demonstrate that seed development occurs under the influence of abundant maternal siRNAs that might be transported to, and function in, filial tissues.
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27
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Singh J, Mishra V, Wang F, Huang HY, Pikaard CS. Reaction Mechanisms of Pol IV, RDR2, and DCL3 Drive RNA Channeling in the si RNA-Directed DNA Methylation Pathway. Mol Cell 2020; 75:576-589.e5. [PMID: 31398324 DOI: 10.1016/j.molcel.2019.07.008] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 05/24/2019] [Accepted: 07/08/2019] [Indexed: 11/16/2022]
Abstract
In eukaryotes with multiple small RNA pathways, the mechanisms that channel RNAs within specific pathways are unclear. Here, we reveal the reactions that account for channeling in the small interfering RNA (siRNA) biogenesis phase of the Arabidopsis RNA-directed DNA methylation pathway. The process begins with template DNA transcription by NUCLEAR RNA POLYMERASE IV (Pol IV), whose atypical termination mechanism, induced by nontemplate DNA base-pairing, channels transcripts to the associated RNA-dependent RNA polymerase RDR2. RDR2 converts Pol IV transcripts into double-stranded RNAs and then typically adds an extra untemplated 3' terminal nucleotide to the second strands. The dicer endonuclease DCL3 cuts resulting duplexes to generate 24- and 23-nt siRNAs. The 23-nt RNAs bear the untemplated terminal nucleotide of the RDR2 strand and are underrepresented among ARGONAUTE4-associated siRNAs. Collectively, our results provide mechanistic insights into Pol IV termination, Pol IV-RDR2 coupling, and RNA channeling, from template DNA transcription to siRNA strand discrimination.
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Affiliation(s)
- Jasleen Singh
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405, USA
| | - Vibhor Mishra
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405, USA; Howard Hughes Medical Institute, Indiana University, Bloomington, IN 47405, USA
| | - Feng Wang
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405, USA; Howard Hughes Medical Institute, Indiana University, Bloomington, IN 47405, USA
| | - Hsiao-Yun Huang
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405, USA
| | - Craig S Pikaard
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405, USA; Howard Hughes Medical Institute, Indiana University, Bloomington, IN 47405, USA.
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28
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Guzmán-Benito I, Donaire L, Amorim-Silva V, Vallarino JG, Esteban A, Wierzbicki AT, Ruiz-Ferrer V, Llave C. The immune repressor BIR1 contributes to antiviral defense and undergoes transcriptional and post-transcriptional regulation during viral infections. New Phytol 2019; 224:421-438. [PMID: 31111491 PMCID: PMC6711825 DOI: 10.1111/nph.15931] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 05/15/2019] [Indexed: 06/09/2023]
Abstract
BIR1 is a receptor-like kinase that functions as a negative regulator of basal immunity and cell death in Arabidopsis. Using Arabidopsis thaliana and Tobacco rattle virus (TRV), we investigate the antiviral role of BIR1, the molecular mechanisms of BIR1 gene expression regulation during viral infections, and the effects of BIR1 overexpression on plant immunity and development. We found that SA acts as a signal molecule for BIR1 activation during infection. Inactivating mutations of BIR1 in the bir1-1 mutant cause strong antiviral resistance independently of constitutive cell death or SA defense priming. BIR1 overexpression leads to severe developmental defects, cell death and premature death, which correlate with the constitutive activation of plant immune responses. Our findings suggest that BIR1 acts as a negative regulator of antiviral defense in plants, and indicate that RNA silencing contributes, alone or in conjunction with other regulatory mechanisms, to define a threshold expression for proper BIR1 function beyond which an autoimmune response may occur. This work provides novel mechanistic insights into the regulation of BIR1 homeostasis that may be common for other plant immune components.
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Affiliation(s)
- Irene Guzmán-Benito
- Departmento de Biotecnología Microbiana y de Plantas, Centro de Investigaciones Biológicas, CSIC, 28040-Madrid, Spain
- Doctorado en Biotecnología y Recursos Genéticos de Plantas y Microorganismos Asociados, ETSI Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040-Madrid, Spain
| | - Livia Donaire
- Departmento de Biotecnología Microbiana y de Plantas, Centro de Investigaciones Biológicas, CSIC, 28040-Madrid, Spain
| | - Vítor Amorim-Silva
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterranea “La Mayora”, Universidad de Málaga-CSIC (IHSM-UMA-CSIC), Universidad de Málaga, Campus Teatinos, 29071-Málaga, Spain
| | - José G. Vallarino
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterranea “La Mayora”, Universidad de Málaga-CSIC (IHSM-UMA-CSIC), Universidad de Málaga, Campus Teatinos, 29071-Málaga, Spain
| | - Alicia Esteban
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterranea “La Mayora”, Universidad de Málaga-CSIC (IHSM-UMA-CSIC), Universidad de Málaga, Campus Teatinos, 29071-Málaga, Spain
| | - Andrzej T. Wierzbicki
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Virginia Ruiz-Ferrer
- Departmento de Biotecnología Microbiana y de Plantas, Centro de Investigaciones Biológicas, CSIC, 28040-Madrid, Spain
| | - César Llave
- Departmento de Biotecnología Microbiana y de Plantas, Centro de Investigaciones Biológicas, CSIC, 28040-Madrid, Spain
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29
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Zhang Y, Ramming A, Heinke L, Altschmied L, Slotkin RK, Becker JD, Kappel C, Lenhard M. The poly(A) polymerase PAPS1 interacts with the RNA-directed DNA-methylation pathway in sporophyte and pollen development. Plant J 2019; 99:655-672. [PMID: 31009115 DOI: 10.1111/tpj.14348] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 03/21/2019] [Accepted: 04/08/2019] [Indexed: 05/28/2023]
Abstract
RNA-based processes play key roles in the regulation of eukaryotic gene expression. This includes both the processing of pre-mRNAs into mature mRNAs ready for translation and RNA-based silencing processes, such as RNA-directed DNA methylation (RdDM). Polyadenylation of pre-mRNAs is one important step in their processing and is carried out by three functionally specialized canonical nuclear poly(A) polymerases in Arabidopsis thaliana. Null mutations in one of these, termed PAPS1, result in a male gametophytic defect. Using a fluorescence-labelling strategy, we have characterized this defect in more detail using RNA and small-RNA sequencing. In addition to global defects in the expression of pollen-differentiation genes, paps1 null-mutant pollen shows a strong overaccumulation of transposable element (TE) transcripts, yet a depletion of 21- and particularly 24-nucleotide-long short interfering RNAs (siRNAs) and microRNAs (miRNAs) targeting the corresponding TEs. Double-mutant analyses support a specific functional interaction between PAPS1 and components of the RdDM pathway, as evident from strong synergistic phenotypes in mutant combinations involving paps1, but not paps2 paps4, mutations. In particular, the double-mutant of paps1 and rna-dependent rna polymerase 6 (rdr6) shows a synergistic developmental phenotype disrupting the formation of the transmitting tract in the female gynoecium. Thus, our findings in A. thaliana uncover a potentially general link between canonical poly(A) polymerases as components of mRNA processing and RdDM, reflecting an analogous interaction in fission yeast.
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Affiliation(s)
- Yunming Zhang
- Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476, Potsdam-Golm, Germany
| | - Anna Ramming
- Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476, Potsdam-Golm, Germany
| | - Lisa Heinke
- Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476, Potsdam-Golm, Germany
| | - Lothar Altschmied
- Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung, Corrensstrasse 3, D-06466 Seeland, OT, Gatersleben, Germany
| | - R Keith Slotkin
- Donald Danforth Plant Science Center, 975 North Warson Road, St Louis, MO, 63132, USA
- Division of Biological Sciences, University of Missouri, Columbia, MO, 65211, USA
| | - Jörg D Becker
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156, Oeiras, Portugal
| | - Christian Kappel
- Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476, Potsdam-Golm, Germany
| | - Michael Lenhard
- Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476, Potsdam-Golm, Germany
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30
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Matsunaga W, Shimura H, Shirakawa S, Isoda R, Inukai T, Matsumura T, Masuta C. Transcriptional silencing of 35S driven-transgene is differentially determined depending on promoter methylation heterogeneity at specific cytosines in both plus- and minus-sense strands. BMC Plant Biol 2019; 19:24. [PMID: 30642254 PMCID: PMC6332629 DOI: 10.1186/s12870-019-1628-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 01/02/2019] [Indexed: 05/18/2023]
Abstract
BACKGROUND De novo DNA methylation triggered by short interfering RNAs is called RNA-directed DNA methylation (RdDM). Transcriptional gene silencing (TGS) through RdDM can be induced using a viral vector. We have previously induced RdDM on the 35S promoter in the green fluorescent protein (GFP)-expressing Nicotiana benthamiana line 16c using the cucumber mosaic virus vector. The GFP fluorescence phenotype segregated into two types, "red" and "orange" in the first self-fertilized (S1) progeny plants by the difference in degree of recovery from TGS on GFP expression. In the second self-fertilized generation (S2 plants), the phenotypes again segregated. Explaining what generates the red and orange types could answer a very important question in epigenetics: How is the robustness of TGS maintained after RdDM induction? RESULTS In bisulfite sequencing analyses, we found a significant difference in the overall promoter hypermethylation pattern between the red and orange types in S1 plants but little difference in S2 plants. Therefore, we assumed that methylation at some specific cytosine residues might be important in determining the two phenotypes. To find the factor that discriminates stable, robust TGS from the unstable TGS with incomplete inheritance, we analyzed the direct effect of methylated cytosine residues on TGS. Because it has not yet been demonstrated that DNA methylation at a few specific cytosine residues on known sequence elements can indeed determine TGS robustness, we newly developed a method by which we can directly evaluate the effect of specific methylation on promoter activity. In this assay, we found that the effects of the specific cytosine methylation on TGS differed between the plus- and minus-strands. CONCLUSIONS We found two distinct phenotypes, the stable and unstable TGS in the progenies of virus-induced TGS plants. Our bisulfite sequencing analyses suggested that methylation at some specific cytosine residues in the 35S promoter played a role in determining whether stable or unstable TGSs are induced. Using the developed method, we inferred that DNA methylation heterogeneity in and between the plus- and minus-strands can differentially determine TGS.
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Affiliation(s)
- Wataru Matsunaga
- Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, 060-8589 Japan
| | - Hanako Shimura
- Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, 060-8589 Japan
| | - Senri Shirakawa
- Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, 060-8589 Japan
| | - Reika Isoda
- Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, 060-8589 Japan
| | - Tsuyoshi Inukai
- Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, 060-8589 Japan
| | - Takeshi Matsumura
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2-17-2-1 Tsukisamu-Higashi, Toyohira-ku, Sapporo, 062-8517 Japan
| | - Chikara Masuta
- Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, 060-8589 Japan
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Wakasa Y, Kawakatsu T, Harada T, Takaiwa F. Transgene-independent heredity of RdDM-mediated transcriptional gene silencing of endogenous genes in rice. Plant Biotechnol J 2018; 16:2007-2015. [PMID: 29704881 PMCID: PMC6230945 DOI: 10.1111/pbi.12934] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 03/27/2018] [Accepted: 04/03/2018] [Indexed: 05/05/2023]
Abstract
To induce transcriptional gene silencing (TGS) of endogenous genes of rice (Oryza sativa L.), we expressed double-strand RNA of each promoter region and thus induced RNA-directed DNA methylation (RdDM). We targeted constitutively expressed genes encoding calnexin (CNX), protein disulphide isomerase (PDIL1-1) and luminal binding protein (BiP1); an endoplasmic reticulum stress-inducible gene (OsbZIP50); and genes with seed-specific expression encoding α-globulin (Glb-1) and glutelin-B4 (GluB4). TGS of four genes was obtained with high efficiency (CNX, 66.7% of regenerated plants; OsBiP1, 67.4%; OsbZIP50, 63.4%; GluB4, 66.1%), whereas the efficiency was lower for PDIL1-1 (33.3%) and Glb-1 TGS lines (10.5%). The heredity of TGS, methylation levels of promoter regions and specificity of silencing of the target gene were investigated in some of the TGS lines. In progeny of CNX and OsbZIP50 TGS lines, suppression of the target genes was preserved (except in the endosperm) even after the removal of trigger genes (T-DNA) by segregation. TGS of CNX was reverted by demethylation treatment, and a significant difference in CG and CHG methylation levels in the -1 to -250 bp region of the CNX promoter was detected between the TGS and revertant lines, suggesting that TGS is closely related to the methylation levels of promoter. TGS exhibited specific suppression towards the target gene compared with post-transcriptional gene silencing when GluB4 gene from glutelin multigene family was targeted. Based on these results, future perspectives and problems to be solved in the application of RdDM to new plant breeding techniques in rice are discussed.
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Affiliation(s)
- Yuhya Wakasa
- Plant Molecular Farming UnitInstitute of Agrobiological SciencesNational Agriculture and Food Research OrganizationTsukubaJapan
| | - Taiji Kawakatsu
- Plant Molecular Farming UnitInstitute of Agrobiological SciencesNational Agriculture and Food Research OrganizationTsukubaJapan
| | - Takeo Harada
- Faculty of Agriculture and Life ScienceHirosaki UniversityHirosakiJapan
| | - Fumio Takaiwa
- Plant Molecular Farming UnitInstitute of Agrobiological SciencesNational Agriculture and Food Research OrganizationTsukubaJapan
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32
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Zhang M, Liu XK, Fan W, Yan DF, Zhong NS, Gao JY, Zhang WJ. Transcriptome analysis reveals hybridization-induced genome shock in an interspecific F 1 hybrid from Camellia. Genome 2018; 61:477-485. [PMID: 29718690 DOI: 10.1139/gen-2017-0105] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The combination of two divergent genomes during hybridization can result in "genome shock". Although genome shock has been reported in the hybrids of some herbaceous plants, the pattern and the principle it follows are far from understood, especially in woody plants. Here, the gene expression patterns were remodeled in the F1 hybrid from the crossing of Camellia azalea × Camellia amplexicaulis compared with the parents as revealed by RNA-seq. About 54.5% of all unigenes were differentially expressed between the F1 hybrid and at least one of the parents, including 6404 unigenes with the highest expression level in the F1 hybrid. A series of genes, related to flower development, essential for RNA-directed DNA methylation and histone methylation, as well as 223 transposable elements, were enriched; and most of them exhibited a higher level of expression in the F1 hybrid. These results indicated that the genome shock induced by interspecific hybridization in Camellia could indeed result in changes of gene expression patterns, potentially through regulating DNA methylation and histone methylation which may be helpful for the maintaining of genome stability and even related to the unique phenotype of the F1 hybrid.
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Affiliation(s)
- Min Zhang
- a Institute of Biodiversity Science, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xin-Kai Liu
- b Palm Eco-Town Development Co., Ltd., Guangzhou, Guangdong 510627, China
| | - Wen Fan
- a Institute of Biodiversity Science, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Dan-Feng Yan
- b Palm Eco-Town Development Co., Ltd., Guangzhou, Guangdong 510627, China
| | - Nai-Sheng Zhong
- b Palm Eco-Town Development Co., Ltd., Guangzhou, Guangdong 510627, China
| | - Ji-Yin Gao
- b Palm Eco-Town Development Co., Ltd., Guangzhou, Guangdong 510627, China.,c Research Institute of Subtropical Forest, Chinese Academy of Forestry, Fuyang, Zhejiang 311400, China
| | - Wen-Ju Zhang
- a Institute of Biodiversity Science, School of Life Sciences, Fudan University, Shanghai 200438, China
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Grover JW, Kendall T, Baten A, Burgess D, Freeling M, King GJ, Mosher RA. Maternal components of RNA-directed DNA methylation are required for seed development in Brassica rapa. Plant J 2018; 94:575-582. [PMID: 29569777 DOI: 10.1111/tpj.13910] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 03/10/2018] [Accepted: 03/13/2018] [Indexed: 05/20/2023]
Abstract
Small RNAs trigger repressive DNA methylation at thousands of transposable elements in a process called RNA-directed DNA methylation (RdDM). The molecular mechanism of RdDM is well characterized in Arabidopsis, yet the biological function remains unclear, as loss of RdDM in Arabidopsis causes no overt defects, even after generations of inbreeding. It is known that 24 nucleotide Pol IV-dependent siRNAs, the hallmark of RdDM, are abundant in flowers and developing seeds, indicating that RdDM might be important during reproduction. Here we show that, unlike Arabidopsis, mutations in the Pol IV-dependent small RNA pathway cause severe and specific reproductive defects in Brassica rapa. High rates of abortion occur when seeds have RdDM mutant mothers, but not when they have mutant fathers. Although abortion occurs after fertilization, RdDM function is required in maternal somatic tissue, not in the female gametophyte or the developing zygote, suggesting that siRNAs from the maternal soma might function in filial tissues. We propose that recently outbreeding species such as B. rapa are key to understanding the role of RdDM during plant reproduction.
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Affiliation(s)
- Jeffrey W Grover
- Department of Molecular & Cellular Biology, The University of Arizona, Tucson, AZ, 85721, USA
| | - Timmy Kendall
- The School of Plant Sciences, The University of Arizona, Tucson, AZ, 85721, USA
| | - Abdul Baten
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW, 2480, Australia
| | - Diane Burgess
- Department of Plant and Microbial Biology, The University of California, Berkeley, CA, 94720, USA
| | - Michael Freeling
- Department of Plant and Microbial Biology, The University of California, Berkeley, CA, 94720, USA
| | - Graham J King
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW, 2480, Australia
| | - Rebecca A Mosher
- Department of Molecular & Cellular Biology, The University of Arizona, Tucson, AZ, 85721, USA
- The School of Plant Sciences, The University of Arizona, Tucson, AZ, 85721, USA
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34
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Grover JW, Kendall T, Baten A, Burgess D, Freeling M, King GJ, Mosher RA. Maternal components of RNA-directed DNA methylation are required for seed development in Brassica rapa. Plant J 2018; 94:573-574. [PMID: 29569777 DOI: 10.1111/tpj.13935] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 03/10/2018] [Accepted: 03/13/2018] [Indexed: 05/24/2023]
Abstract
Small RNAs trigger repressive DNA methylation at thousands of transposable elements in a process called RNA-directed DNA methylation (RdDM). The molecular mechanism of RdDM is well characterized in Arabidopsis, yet the biological function remains unclear, as loss of RdDM in Arabidopsis causes no overt defects, even after generations of inbreeding. It is known that 24 nucleotide Pol IV-dependent siRNAs, the hallmark of RdDM, are abundant in flowers and developing seeds, indicating that RdDM might be important during reproduction. Here we show that, unlike Arabidopsis, mutations in the Pol IV-dependent small RNA pathway cause severe and specific reproductive defects in Brassica rapa. High rates of abortion occur when seeds have RdDM mutant mothers, but not when they have mutant fathers. Although abortion occurs after fertilization, RdDM function is required in maternal somatic tissue, not in the female gametophyte or the developing zygote, suggesting that siRNAs from the maternal soma might function in filial tissues. We propose that recently outbreeding species such as B. rapa are key to understanding the role of RdDM during plant reproduction.
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Affiliation(s)
- Jeffrey W Grover
- Department of Molecular & Cellular Biology, The University of Arizona, Tucson, AZ, 85721, USA
| | - Timmy Kendall
- The School of Plant Sciences, The University of Arizona, Tucson, AZ, 85721, USA
| | - Abdul Baten
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW, 2480, Australia
| | - Diane Burgess
- Department of Plant and Microbial Biology, The University of California, Berkeley, CA, 94720, USA
| | - Michael Freeling
- Department of Plant and Microbial Biology, The University of California, Berkeley, CA, 94720, USA
| | - Graham J King
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW, 2480, Australia
| | - Rebecca A Mosher
- Department of Molecular & Cellular Biology, The University of Arizona, Tucson, AZ, 85721, USA
- The School of Plant Sciences, The University of Arizona, Tucson, AZ, 85721, USA
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35
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Abstract
Background Freakish and rare or the tip of the iceberg? Both phrases have been used to refer to paramutation, an epigenetic drive that contravenes Mendel’s first law of segregation. Although its underlying mechanisms are beginning to unravel, its understanding relies only on a few examples that may involve transgenes or artificially generated epialleles. Results By using DNA methylation of introgression lines as an indication of past paramutation, we reveal that the paramutation-like properties of the H06 locus in hybrids of Solanum lycopersicum and a range of tomato relatives and cultivars depend on the timing of sRNA production and conform to an RNA-directed mechanism. In addition, by scanning the methylomes of tomato introgression lines for shared regions of differential methylation that are absent in the S. lycopersicum parent, we identify thousands of candidate regions for paramutation-like behaviour. The methylation patterns for a subset of these regions segregate with non Mendelian ratios, consistent with secondary paramutation-like interactions to variable extents depending on the locus. Conclusion Together these results demonstrate that paramutation-like epigenetic interactions are common for natural epialleles in tomato, but vary in timing and penetrance. Electronic supplementary material The online version of this article (10.1186/s12864-018-4590-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Quentin Gouil
- Present address: Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, 3052, Australia. .,Department of Plant Sciences, University of Cambridge, Downing Site, Cambridge, CB2 3EA, UK.
| | - David C Baulcombe
- Department of Plant Sciences, University of Cambridge, Downing Site, Cambridge, CB2 3EA, UK.
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36
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Tamiru M, Hardcastle TJ, Lewsey MG. Regulation of genome-wide DNA methylation by mobile small RNAs. New Phytol 2018; 217:540-546. [PMID: 29105762 DOI: 10.1111/nph.14874] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 09/20/2017] [Indexed: 05/20/2023]
Abstract
Contents Summary 540 I. Introduction 540 II. There are different types of sRNA mobility 541 III. Mechanisms of sRNA movement 541 IV. Long-distance, shoot-root, mobile siRNAs influence DNA methylation in recipient tissues 541 V. Classes of interactions between shoot-root mobile siRNAs and DNA methylation 542 VI. Loci targeted directly and indirectly by shoot-root mobile siRNAs are associated with different histone modifications 543 VII. Is mobile siRNA-regulated DNA methylation important in specific tissues or under specific conditions? 543 VIII. Mobile sRNAs can be used to modify plant traits 544 IX. Conclusions 544 Acknowledgements 544 References 544 SUMMARY: RNA-directed DNA methylation (RdDM) at cytosine residues regulates gene expression, silences transposable elements and influences genome stability. The mechanisms responsible for RdDM are guided to target loci by small RNAs (sRNAs) that can move within plants cell to cell and long distance. Here we discuss recent advances in the understanding of interactions between mobile sRNAs and DNA methylation. We describe the mechanisms of sRNA movement, the differences between known classes of mobile sRNA-DNA methylation interactions and the limits of current knowledge. Finally, we discuss potential applications of mobile sRNAs in modifying plant traits.
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Affiliation(s)
- Muluneh Tamiru
- Centre for AgriBioscience, Department of Animal, Plant and Soil Science, School of Life Science, La Trobe University, Bundoora, Vic., 3086, Australia
| | - Thomas J Hardcastle
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK
| | - Mathew G Lewsey
- Centre for AgriBioscience, Department of Animal, Plant and Soil Science, School of Life Science, La Trobe University, Bundoora, Vic., 3086, Australia
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37
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Wang J, Meng X, Dobrovolskaya OB, Orlov YL, Chen M. Non-coding RNAs and Their Roles in Stress Response in Plants. Genomics Proteomics Bioinformatics 2017; 15:301-312. [PMID: 29017967 PMCID: PMC5673675 DOI: 10.1016/j.gpb.2017.01.007] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 01/04/2017] [Accepted: 01/26/2017] [Indexed: 02/04/2023]
Abstract
Eukaryotic genomes encode thousands of non-coding RNAs (ncRNAs), which play crucial roles in transcriptional and post-transcriptional regulation of gene expression. Accumulating evidence indicates that ncRNAs, especially microRNAs (miRNAs) and long ncRNAs (lncRNAs), have emerged as key regulatory molecules in plant stress responses. In this review, we have summarized the current progress on the understanding of plant miRNA and lncRNA identification, characteristics, bioinformatics tools, and resources, and provided examples of mechanisms of miRNA- and lncRNA-mediated plant stress tolerance.
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Affiliation(s)
- Jingjing Wang
- Department of Bioinformatics, State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China; James D. Watson Institute of Genome Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xianwen Meng
- Department of Bioinformatics, State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Oxana B Dobrovolskaya
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia; Novosibirsk State University, Novosibirsk 630090, Russia
| | - Yuriy L Orlov
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Ming Chen
- Department of Bioinformatics, State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China; James D. Watson Institute of Genome Sciences, Zhejiang University, Hangzhou 310058, China.
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38
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Au PCK, Dennis ES, Wang MB. Analysis of Argonaute 4-Associated Long Non-Coding RNA in Arabidopsis thaliana Sheds Novel Insights into Gene Regulation through RNA-Directed DNA Methylation. Genes (Basel) 2017; 8:E198. [PMID: 28783101 PMCID: PMC5575662 DOI: 10.3390/genes8080198] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 08/01/2017] [Accepted: 08/02/2017] [Indexed: 12/20/2022] Open
Abstract
RNA-directed DNA methylation (RdDM) is a plant-specific de novo DNA methylation mechanism that requires long noncoding RNA (lncRNA) as scaffold to define target genomic loci. While the role of RdDM in maintaining genome stability is well established, how it regulates protein-coding genes remains poorly understood and few RdDM target genes have been identified. In this study, we obtained sequences of RdDM-associated lncRNAs using nuclear RNA immunoprecipitation against ARGONAUTE 4 (AGO4), a key component of RdDM that binds specifically with the lncRNA. Comparison of these lncRNAs with gene expression data of RdDM mutants identified novel RdDM target genes. Surprisingly, a large proportion of these target genes were repressed in RdDM mutants suggesting that they are normally activated by RdDM. These RdDM-activated genes are more enriched for gene body lncRNA than the RdDM-repressed genes. Histone modification and RNA analyses of several RdDM-activated stress response genes detected increased levels of active histone mark and short RNA transcript in the lncRNA-overlapping gene body regions in the ago4 mutant despite the repressed expression of these genes. These results suggest that RdDM, or AGO4, may play a role in maintaining or activating stress response gene expression by directing gene body chromatin modification preventing cryptic transcription.
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Affiliation(s)
- Phil Chi Khang Au
- Commonwealth Scientific and Industrial Research Organisation Agriculture, Canberra, Australian Capital Territory 2601, Australia.
| | - Elizabeth S Dennis
- Commonwealth Scientific and Industrial Research Organisation Agriculture, Canberra, Australian Capital Territory 2601, Australia.
| | - Ming-Bo Wang
- Commonwealth Scientific and Industrial Research Organisation Agriculture, Canberra, Australian Capital Territory 2601, Australia.
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Otagaki S, Kasai M, Masuta C, Kanazawa A. Corrigendum: Enhancement of RNA-directed DNA methylation of a transgene by simultaneously downregulating a ROS1 ortholog using a virus vector in Nicotiana benthamiana. Front Genet 2017; 8:5. [PMID: 28167955 PMCID: PMC5285356 DOI: 10.3389/fgene.2017.00005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 01/13/2017] [Indexed: 11/13/2022] Open
Abstract
[This corrects the article on p. 44 in vol. 4, PMID: 23565118.].
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Affiliation(s)
- Shungo Otagaki
- Research Faculty of Agriculture, Hokkaido University Sapporo, Japan
| | - Megumi Kasai
- Research Faculty of Agriculture, Hokkaido University Sapporo, Japan
| | - Chikara Masuta
- Research Faculty of Agriculture, Hokkaido University Sapporo, Japan
| | - Akira Kanazawa
- Research Faculty of Agriculture, Hokkaido University Sapporo, Japan
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40
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Koch A, Kang HG, Steinbrenner J, Dempsey DA, Klessig DF, Kogel KH. MORC Proteins: Novel Players in Plant and Animal Health. Front Plant Sci 2017; 8:1720. [PMID: 29093720 PMCID: PMC5651269 DOI: 10.3389/fpls.2017.01720] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 09/20/2017] [Indexed: 05/02/2023]
Abstract
Microrchidia (MORC) proteins comprise a family of proteins that have been identified in prokaryotes and eukaryotes. They are defined by two hallmark domains: a GHKL-type ATPase and an S5 fold. MORC proteins in plants were first discovered via a genetic screen for Arabidopsis mutants compromised for resistance to a viral pathogen. Subsequent studies expanded their role in plant immunity and revealed their involvement in gene silencing and transposable element repression. Emerging data suggest that MORC proteins also participate in pathogen-induced chromatin remodeling and epigenetic gene regulation. In addition, biochemical analyses recently demonstrated that plant MORCs have topoisomerase II (topo II)-like DNA modifying activities that may be important for their function. Interestingly, animal MORC proteins exhibit many parallels with their plant counterparts, as they have been implicated in disease development and gene silencing. In addition, human MORCs, like plant MORCs, bind salicylic acid and this inhibits some of their topo II-like activities. In this review, we will focus primarily on plant MORCs, although relevant comparisons with animal MORCs will be provided.
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Affiliation(s)
- Aline Koch
- Centre for BioSystems, Land Use and Nutrition, Institute for Phytopathology, Justus Liebig University Giessen, Giessen, Germany
| | - Hong-Gu Kang
- Department of Biology, Texas State University, San Marcos, TX, United States
| | - Jens Steinbrenner
- Centre for BioSystems, Land Use and Nutrition, Institute for Phytopathology, Justus Liebig University Giessen, Giessen, Germany
| | | | - Daniel F. Klessig
- Boyce Thompson Institute for Plant Research, Ithaca, NY, United States
- *Correspondence: Daniel F. Klessig
| | - Karl-Heinz Kogel
- Centre for BioSystems, Land Use and Nutrition, Institute for Phytopathology, Justus Liebig University Giessen, Giessen, Germany
- Karl-Heinz Kogel
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41
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Trujillo JT, Beilstein MA, Mosher RA. The Argonaute-binding platform of NRPE1 evolves through modulation of intrinsically disordered repeats. New Phytol 2016; 212:1094-1105. [PMID: 27431917 PMCID: PMC5125548 DOI: 10.1111/nph.14089] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 06/04/2016] [Indexed: 05/26/2023]
Abstract
Argonaute (Ago) proteins are important effectors in RNA silencing pathways, but they must interact with other machinery to trigger silencing. Ago hooks have emerged as a conserved motif responsible for interaction with Ago proteins, but little is known about the sequence surrounding Ago hooks that must restrict or enable interaction with specific Argonautes. Here we investigated the evolutionary dynamics of an Ago-binding platform in NRPE1, the largest subunit of RNA polymerase V. We compared NRPE1 sequences from > 50 species, including dense sampling of two plant lineages. This study demonstrates that the Ago-binding platform of NRPE1 retains Ago hooks, intrinsic disorder, and repetitive character while being highly labile at the sequence level. We reveal that loss of sequence conservation is the result of relaxed selection and frequent expansions and contractions of tandem repeat arrays. These factors allow a complete restructuring of the Ago-binding platform over 50-60 million yr. This evolutionary pattern is also detected in a second Ago-binding platform, suggesting it is a general mechanism. The presence of labile repeat arrays in all analyzed NRPE1 Ago-binding platforms indicates that selection maintains repetitive character, potentially to retain the ability to rapidly restructure the Ago-binding platform.
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Affiliation(s)
- Joshua T Trujillo
- The School of Plant Sciences, The University of Arizona, Tucson, AZ, 85721-0036, USA
| | - Mark A Beilstein
- The School of Plant Sciences, The University of Arizona, Tucson, AZ, 85721-0036, USA
| | - Rebecca A Mosher
- The School of Plant Sciences, The University of Arizona, Tucson, AZ, 85721-0036, USA
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42
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Abstract
Small (s)RNAs of 21 to 24 nucleotides are associated with RNA silencing and methylation of DNA cytosine residues. All sizes can move from cell-to-cell and long distance in plants, directing RNA silencing in destination cells. Twenty-four nucleotide sRNAs are the predominant long-distance mobile species. Thousands move from shoot to root, where they target methylation of transposable elements both directly and indirectly. We derive several classes of interaction between small RNAs and methylation and use these to explore the mechanisms of methylation and gene expression that associate with mobile sRNA signaling.
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Affiliation(s)
| | - Mathew G Lewsey
- b Department of Animal, Plant and Soil Science, Center for AgriBioscience, School of Life Science , La Trobe University , Bundoora , Australia
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43
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Otagaki S, Kasai M, Masuta C, Kanazawa A. Corrigendum: Enhancement of RNA-directed DNA methylation of a transgene by simultaneously downregulating a ROS1 ortholog using a virus vector in Nicotiana benthamiana. Front Genet 2016; 7:21. [PMID: 26973697 PMCID: PMC4770047 DOI: 10.3389/fgene.2016.00021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 02/02/2016] [Indexed: 11/13/2022] Open
Affiliation(s)
- Shungo Otagaki
- Research Faculty of Agriculture, Hokkaido University Sapporo, Japan
| | - Megumi Kasai
- Research Faculty of Agriculture, Hokkaido University Sapporo, Japan
| | - Chikara Masuta
- Research Faculty of Agriculture, Hokkaido University Sapporo, Japan
| | - Akira Kanazawa
- Research Faculty of Agriculture, Hokkaido University Sapporo, Japan
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Chan Z, Wang Y, Cao M, Gong Y, Mu Z, Wang H, Hu Y, Deng X, He XJ, Zhu JK. RDM4 modulates cold stress resistance in Arabidopsis partially through the CBF-mediated pathway. New Phytol 2016; 209:1527-39. [PMID: 26522658 PMCID: PMC5515388 DOI: 10.1111/nph.13727] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 09/25/2015] [Indexed: 05/20/2023]
Abstract
The C-REPEAT-BINDING FACTOR (CBF) pathway has important roles in plant responses to cold stress. How the CBF genes themselves are activated after cold acclimation remains poorly understood. In this study, we characterized cold tolerance of null mutant of RNA-DIRECTED DNA METHYLATION 4 (RDM4), which encodes a protein that associates with RNA polymerases Pol V and Pol II, and is required for RNA-directed DNA methylation (RdDM) in Arabidopsis. The results showed that dysfunction of RDM4 reduced cold tolerance, as evidenced by decreased survival and increased electrolyte leakage. Mutation of RDM4 resulted in extensive transcriptomic reprogramming. CBFs and CBF regulon genes were down-regulated in rdm4 but not nrpe1 (the largest subunit of PolV) mutants, suggesting that the role of RDM4 in cold stress responses is independent of the RdDM pathway. Overexpression of RDM4 constitutively increased the expression of CBFs and regulon genes and decreased cold-induced membrane injury. A great proportion of genes affected by rdm4 overlapped with those affected by CBFs. Chromatin immunoprecipitation results suggested that RDM4 is important for Pol II occupancy at the promoters of CBF2 and CBF3. We present evidence of a considerable role for RDM4 in regulating gene expression at low temperature, including the CBF pathway in Arabidopsis.
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Affiliation(s)
- Zhulong Chan
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei Province 430074, China
- Shanghai Center for Plant Stress Biology and Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Yanping Wang
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei Province 430074, China
| | - Minjie Cao
- Shanghai Center for Plant Stress Biology and Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Yuehua Gong
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47906, USA
- College of Life Science and Food Engineering, Yibin University, Yibin, Sichuan 644000, China
| | - Zixin Mu
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47906, USA
- College of Life Science, Northwest A&F University, Yangling, Shaan’xi 712100, China
| | - Haiqing Wang
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47906, USA
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Plateau Institute of Biology, Chinese Academy of Sciences, Xining, Qinghai 810001, China
| | - Yuanlei Hu
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47906, USA
- College of Life Sciences, Peking University, Beijing 100871, China
| | - Xin Deng
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47906, USA
- Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Science, Beijing 100093, China
| | - Xin-Jian He
- National Institute of Biological Sciences, Beijing 102206, China
| | - Jian-Kang Zhu
- Shanghai Center for Plant Stress Biology and Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47906, USA
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Lewsey MG, Hardcastle TJ, Melnyk CW, Molnar A, Valli A, Urich MA, Nery JR, Baulcombe DC, Ecker JR. Mobile small RNAs regulate genome-wide DNA methylation. Proc Natl Acad Sci U S A 2016; 113:E801-10. [PMID: 26787884 DOI: 10.1073/pnas.1515072113] [Citation(s) in RCA: 159] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
RNA silencing at the transcriptional and posttranscriptional levels regulates endogenous gene expression, controls invading transposable elements (TEs), and protects the cell against viruses. Key components of the mechanism are small RNAs (sRNAs) of 21-24 nt that guide the silencing machinery to their nucleic acid targets in a nucleotide sequence-specific manner. Transcriptional gene silencing is associated with 24-nt sRNAs and RNA-directed DNA methylation (RdDM) at cytosine residues in three DNA sequence contexts (CG, CHG, and CHH). We previously demonstrated that 24-nt sRNAs are mobile from shoot to root in Arabidopsis thaliana and confirmed that they mediate DNA methylation at three sites in recipient cells. In this study, we extend this finding by demonstrating that RdDM of thousands of loci in root tissues is dependent upon mobile sRNAs from the shoot and that mobile sRNA-dependent DNA methylation occurs predominantly in non-CG contexts. Mobile sRNA-dependent non-CG methylation is largely dependent on the DOMAINS REARRANGED METHYLTRANSFERASES 1/2 (DRM1/DRM2) RdDM pathway but is independent of the CHROMOMETHYLASE (CMT)2/3 DNA methyltransferases. Specific superfamilies of TEs, including those typically found in gene-rich euchromatic regions, lose DNA methylation in a mutant lacking 22- to 24-nt sRNAs (dicer-like 2, 3, 4 triple mutant). Transcriptome analyses identified a small number of genes whose expression in roots is associated with mobile sRNAs and connected to DNA methylation directly or indirectly. Finally, we demonstrate that sRNAs from shoots of one accession move across a graft union and target DNA methylation de novo at normally unmethylated sites in the genomes of root cells from a different accession.
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Blevins T, Podicheti R, Mishra V, Marasco M, Wang J, Rusch D, Tang H, Pikaard CS. Identification of Pol IV and RDR2-dependent precursors of 24 nt siRNAs guiding de novo DNA methylation in Arabidopsis. eLife 2015; 4:e09591. [PMID: 26430765 PMCID: PMC4716838 DOI: 10.7554/elife.09591] [Citation(s) in RCA: 184] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2015] [Accepted: 10/01/2015] [Indexed: 12/21/2022] Open
Abstract
In Arabidopsis thaliana, abundant 24 nucleotide small interfering RNAs (24 nt siRNA) guide the cytosine methylation and silencing of transposons and a subset of genes. 24 nt siRNA biogenesis requires nuclear RNA polymerase IV (Pol IV), RNA-dependent RNA polymerase 2 (RDR2) and DICER-like 3 (DCL3). However, siRNA precursors are mostly undefined. We identified Pol IV and RDR2-dependent RNAs (P4R2 RNAs) that accumulate in dcl3 mutants and are diced into 24 nt RNAs by DCL3 in vitro. P4R2 RNAs are mostly 26-45 nt and initiate with a purine adjacent to a pyrimidine, characteristics shared by Pol IV transcripts generated in vitro. RDR2 terminal transferase activity, also demonstrated in vitro, may account for occasional non-templated nucleotides at P4R2 RNA 3' termini. The 24 nt siRNAs primarily correspond to the 5' or 3' ends of P4R2 RNAs, suggesting a model whereby siRNAs are generated from either end of P4R2 duplexes by single dicing events.
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Affiliation(s)
- Todd Blevins
- Howard Hughes Medical Institute, Indiana University, Bloomington, United States
- Department of Biology, Indiana University, Bloomington, United States
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, United States
| | - Ram Podicheti
- Center for Genomics and Bioinformatics, Indiana University, Bloomington, United States
- School of Informatics and Computing, Indiana University, Bloomington, United States
| | - Vibhor Mishra
- Department of Biology, Indiana University, Bloomington, United States
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, United States
| | - Michelle Marasco
- Department of Biology, Indiana University, Bloomington, United States
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, United States
| | - Jing Wang
- Department of Biology, Indiana University, Bloomington, United States
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, United States
| | - Doug Rusch
- Center for Genomics and Bioinformatics, Indiana University, Bloomington, United States
| | - Haixu Tang
- School of Informatics and Computing, Indiana University, Bloomington, United States
| | - Craig S Pikaard
- Howard Hughes Medical Institute, Indiana University, Bloomington, United States
- Department of Biology, Indiana University, Bloomington, United States
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, United States
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Ma L, Hatlen A, Kelly LJ, Becher H, Wang W, Kovarik A, Leitch IJ, Leitch AR. Angiosperms Are Unique among Land Plant Lineages in the Occurrence of Key Genes in the RNA-Directed DNA Methylation (RdDM) Pathway. Genome Biol Evol 2015; 7:2648-62. [PMID: 26338185 PMCID: PMC4607528 DOI: 10.1093/gbe/evv171] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The RNA-directed DNA methylation (RdDM) pathway can be divided into three phases: 1) small interfering RNA biogenesis, 2) de novo methylation, and 3) chromatin modification. To determine the degree of conservation of this pathway we searched for key genes among land plants. We used OrthoMCL and the OrthoMCL Viridiplantae database to analyze proteomes of species in bryophytes, lycophytes, monilophytes, gymnosperms, and angiosperms. We also analyzed small RNA size categories and, in two gymnosperms, cytosine methylation in ribosomal DNA. Six proteins were restricted to angiosperms, these being NRPD4/NRPE4, RDM1, DMS3 (defective in meristem silencing 3), SHH1 (SAWADEE homeodomain homolog 1), KTF1, and SUVR2, although we failed to find the latter three proteins in Fritillaria persica, a species with a giant genome. Small RNAs of 24 nt in length were abundant only in angiosperms. Phylogenetic analyses of Dicer-like (DCL) proteins showed that DCL2 was restricted to seed plants, although it was absent in Gnetum gnemon and Welwitschia mirabilis. The data suggest that phases (1) and (2) of the RdDM pathway, described for model angiosperms, evolved with angiosperms. The absence of some features of RdDM in F. persica may be associated with its large genome. Phase (3) is probably the most conserved part of the pathway across land plants. DCL2, involved in virus defense and interaction with the canonical RdDM pathway to facilitate methylation of CHH, is absent outside seed plants. Its absence in G. gnemon, and W. mirabilis coupled with distinctive patterns of CHH methylation, suggest a secondary loss of DCL2 following the divergence of Gnetales.
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Affiliation(s)
- Lu Ma
- School of Biological and Chemical Sciences, Queen Mary University of London, United Kingdom
| | - Andrea Hatlen
- School of Biological and Chemical Sciences, Queen Mary University of London, United Kingdom
| | - Laura J Kelly
- School of Biological and Chemical Sciences, Queen Mary University of London, United Kingdom
| | - Hannes Becher
- School of Biological and Chemical Sciences, Queen Mary University of London, United Kingdom
| | - Wencai Wang
- School of Biological and Chemical Sciences, Queen Mary University of London, United Kingdom
| | - Ales Kovarik
- Department of Molecular Epigenetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
| | - Ilia J Leitch
- Department of Comparative Plant and Fungal Biology Royal Botanic Gardens, Kew, Richmond, Surrey, United Kingdom
| | - Andrew R Leitch
- School of Biological and Chemical Sciences, Queen Mary University of London, United Kingdom
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Xu R, Wang Y, Zheng H, Lu W, Wu C, Huang J, Yan K, Yang G, Zheng C. Salt-induced transcription factor MYB74 is regulated by the RNA-directed DNA methylation pathway in Arabidopsis. J Exp Bot 2015; 66:5997-6008. [PMID: 26139822 PMCID: PMC4566987 DOI: 10.1093/jxb/erv312] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Salt stress is one of the major abiotic stresses in agriculture worldwide that causes crop failure by interfering with the profile of gene expression and cell metabolism. Transcription factors and RNA-directed DNA methylation (RdDM) play an important role in the regulation of gene activation under abiotic stress in plants. This work characterized AtMYB74, a member of the R2R3-MYB gene family, which is transcriptionally regulated mainly by RdDM as a response in salt stress in Arabidopsis. Bisulphite sequencing indicated that 24-nt siRNAs target a region approximately 500bp upstream of the transcription initiation site of AtMYB74, which is heavily methylated. Levels of DNA methylation in this region were significantly reduced in wild type plants under salt stress, whereas no changes were found in RdDM mutants. Northern blot and quantitative real-time reverse transcription PCR analysis showed that the accumulation of 24-nt siRNAs was decreased in WT plants under salt stress. Further promoter deletion analysis revealed that the siRNA target region is essential for maintaining AtMYB74 expression patterns. In addition, transgenic plants overexpressing AtMYB74 displayed hypersensitivity to NaCl during seed germination. These results suggest that changes in the levels of the five 24-nt siRNAs regulate the AtMYB74 transcription factor via RdDM in response to salt stress.
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Affiliation(s)
- Rui Xu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, PR China Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, PR China
| | - Yuhan Wang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, PR China
| | - Hao Zheng
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, PR China
| | - Wei Lu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, PR China
| | - Changai Wu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, PR China
| | - Jinguang Huang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, PR China
| | - Kang Yan
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, PR China
| | - Guodong Yang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, PR China
| | - Chengchao Zheng
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, PR China
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Deng S, Chua NH. Inverted-Repeat RNAs Targeting FT Intronic Regions Promote FT Expression in Arabidopsis. Plant Cell Physiol 2015; 56:1667-78. [PMID: 26076969 DOI: 10.1093/pcp/pcv091] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 06/11/2015] [Indexed: 05/04/2023]
Abstract
Transcriptional gene silencing (TGS) is often associated with promoter methylation in both animals and plants. However, the function of DNA methylation in the intragenic region remains unclear. Here, we confirmed that promoter methylation of FLOWERING LOCUS T (FT) led to gene silencing; in contrast, we found that intragenic methylation triggered by RNA-directed DNA methylation (RdDM) promoted FT expression. DNA methylation of the FT gene body blocked FLC repressor binding to the CArG boxes. However, when the boxes were not directly targeted by inverted-repeat RNAs (IRs), FLC binding blocked spreading of DNA methylation to theses sequences. Notwithstanding the FLC binding, FT was still activated under this condition. The DNA methylation was accompanied by elevated H3K9 methylation levels on the FT gene body. More importantly, the FT diurnal and organ-specific expression pattern was preserved in the activated plants. Our data demonstrate that the same type of epigenetic modification can lead to an opposite genetic outcome depending on the location of the modification on the gene locus. Moreover, we highlight a novel strategy to activate gene expression without changing its spatio-temporal regulatory patterns.
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Affiliation(s)
- Shulin Deng
- Laboratory of Plant Molecular Biology, The Rockefeller University, 1230, York Avenue, New York, NY 10065, USA
| | - Nam-Hai Chua
- Laboratory of Plant Molecular Biology, The Rockefeller University, 1230, York Avenue, New York, NY 10065, USA
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50
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Bond DM, Baulcombe DC. Epigenetic transitions leading to heritable, RNA-mediated de novo silencing in Arabidopsis thaliana. Proc Natl Acad Sci U S A 2015; 112:917-22. [PMID: 25561534 DOI: 10.1073/pnas.1413053112] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
In plants, RNA-directed DNA methylation (RdDM), a mechanism where epigenetic modifiers are guided to target loci by small RNAs, plays a major role in silencing of transposable elements (TEs) to maintain genome integrity. So far, two RdDM pathways have been identified: RNA Polymerase IV (PolIV)-RdDM and RNA-dependent RNA Polymerase 6 (RDR6)-RdDM. PolIV-RdDM involves a self-reinforcing feedback mechanism that maintains TE silencing, but cannot explain how epigenetic silencing is first initiated. A function of RDR6-RdDM is to reestablish epigenetic silencing of active TEs, but it is unknown if this pathway can induce DNA methylation at naïve, non-TE loci. To investigate de novo establishment of RdDM, we have used virus-induced gene silencing (VIGS) of an active flowering Wageningen epiallele. Using genetic mutants we show that unlike PolIV-RdDM, but like RDR6-RdDM, establishment of VIGS-mediated RdDM requires PolV and DRM2 but not Dicer like-3 and other PolIV pathway components. DNA methylation in VIGS is likely initiated by a process guided by virus-derived small (s) RNAs that are 21/22-nt in length and reinforced or maintained by 24-nt sRNAs. We demonstrate that VIGS-RdDM as a tool for gene silencing can be enhanced by use of mutant plants with increased production of 24-nt sRNAs to reinforce the level of RdDM.
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