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Catoni M, Zabet NR. Analysis of Plant DNA Methylation Profiles Using R. Methods Mol Biol 2021; 2250:219-238. [PMID: 33900608 DOI: 10.1007/978-1-0716-1134-0_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
DNA methylation is a transgenerational stable epigenetic modification able to regulate gene expression and genome stability. The analysis of DNA methylation by genome-wide bisulfite sequencing become the main genomic approach to study epigenetics in many organisms; leading to standardization of the alignment and methylation call procedures. However, subsequent steps of the computational analysis should be tailored to the biological questions and the organisms used. Since most bioinformatics tools designed for epigenetic studies are built using mammalian models, they are potentially unsuitable for organisms with substantially different epigenetic regulation, such as plants. Therefore, in this chapter we propose a computational workflow for the analysis, visualization, and interpretation of data obtained from alignment of whole genome bisulfite sequencing of plant samples. Using almost exclusively the R working environment we will examine in depth how to tackle some plant-related issues during epigenetic analysis.
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Affiliation(s)
- Marco Catoni
- School of Biosciences, University of Birmingham, Birmingham, B15 2TT, UK.
| | - Nicolae Radu Zabet
- School of Biological Sciences, University of Essex, Colchester, CO4 3SQ, UK.
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, E1 2AT, UK.
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52
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Ritter EJ, Niederhuth CE. Intertwined evolution of plant epigenomes and genomes. CURRENT OPINION IN PLANT BIOLOGY 2021; 61:101990. [PMID: 33445143 DOI: 10.1016/j.pbi.2020.101990] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/08/2020] [Accepted: 12/17/2020] [Indexed: 06/12/2023]
Abstract
DNA methylation is found across eukaryotes; however, plants have evolved patterns and pathways of DNA methylation that are distinct from animals and fungi. DNA methylation shapes the evolution of genomes through its direct roles in transposon silencing, gene expression, genome stability, and its impact on mutation rates. In return the diversity of DNA methylation across species is shaped by genome sequence evolution. Extensive diversification of key DNA methylation pathways has continued in plants through gene duplication and loss. Meanwhile, frequent movement of transposons has altered local DNA methylation patterns and the genes affected. Only recently has the diversity and evolutionary history of plant DNA methylation become evident with the availability of increasing genomic and epigenomic data. However, much remains unresolved regarding the evolutionary forces that have shaped the dynamics of the complex and intertwined history of plant genome and epigenome evolution.
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Affiliation(s)
- Eleanore J Ritter
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Chad E Niederhuth
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824, USA; AgBioResearch, Michigan State University, East Lansing, MI 48824, USA.
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53
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DNA methylation: from model plants to vegetable crops. Biochem Soc Trans 2021; 49:1479-1487. [PMID: 34060587 DOI: 10.1042/bst20210353] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 04/29/2021] [Accepted: 05/07/2021] [Indexed: 11/17/2022]
Abstract
As a subgroup of horticultural crops, vegetable food is a kind of indispensable energy source for human beings, providing necessary nutritional components including vitamins, carbohydrates, dietary fiber, and active substances such as carotenoids and flavonoids. The developmental process of vegetable crops is not only regulated by environmental stimulations, but also manipulated by both genetic and epigenetic modifications. Epigenetic modifications are composed by several regulatory mechanisms, including DNA methylation, histone modification, chromatin remodeling, and non-coding RNAs. Among these modifications, DNA methylation functions in multiple biological pathways ranging from fundamental development to environmental stimulations by mediating transcriptomic alterations, resulting in the activation or silencing of target genes. In recent years, intensive studies have revealed that DNA methylation is essential to fruit development and ripening, indicating that the epigenome of fruit crops could be dynamically modified according to the specific requirements in the commercial production. Firstly, this review will present the mechanisms of DNA methylation, and update the understanding on active DNA demethylation in Arabidopsis thaliana. Secondly, this review will summarize the recent progress on the function of DNA methylation in regulating fruit ripening. Moreover, the possible functions of DNA methylation on controlling the expansion of edible organs, senescence of leafy vegetables, and anthocyanin pigmentation in several important vegetable crops will be discussed. Finally, this review will highlight the intractable issues that need to be resolved in the application of epigenome in vegetable crops, and provide perspectives for the potential challenges in the further studies.
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Fang J, Leichter SM, Jiang J, Biswal M, Lu J, Zhang ZM, Ren W, Zhai J, Cui Q, Zhong X, Song J. Substrate deformation regulates DRM2-mediated DNA methylation in plants. SCIENCE ADVANCES 2021; 7:eabd9224. [PMID: 34078593 PMCID: PMC8172135 DOI: 10.1126/sciadv.abd9224] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 04/16/2021] [Indexed: 06/12/2023]
Abstract
DNA methylation is a major epigenetic mechanism critical for gene expression and genome stability. In plants, domains rearranged methyltransferase 2 (DRM2) preferentially mediates CHH (H = C, T, or A) methylation, a substrate specificity distinct from that of mammalian DNA methyltransferases. However, the underlying mechanism is unknown. Here, we report structure-function characterization of DRM2-mediated methylation. An arginine finger from the catalytic loop intercalates into the nontarget strand of DNA through the minor groove, inducing large DNA deformation that affects the substrate preference of DRM2. The target recognition domain stabilizes the enlarged major groove via shape complementarity rather than base-specific interactions, permitting substrate diversity. The engineered DRM2 C397R mutation introduces base-specific contacts with the +2-flanking guanine, thereby shifting the substrate specificity of DRM2 toward CHG DNA. Together, this study uncovers DNA deformation as a mechanism in regulating the specificity of DRM2 toward diverse CHH substrates and illustrates methylome complexity in plants.
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Affiliation(s)
- Jian Fang
- Department of Biochemistry, University of California, Riverside, Riverside, CA 92521, USA
| | - Sarah M Leichter
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI 53715, USA
| | - Jianjun Jiang
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI 53715, USA
| | - Mahamaya Biswal
- Department of Biochemistry, University of California, Riverside, Riverside, CA 92521, USA
| | - Jiuwei Lu
- Department of Biochemistry, University of California, Riverside, Riverside, CA 92521, USA
| | - Zhi-Min Zhang
- Department of Biochemistry, University of California, Riverside, Riverside, CA 92521, USA
| | - Wendan Ren
- Department of Biochemistry, University of California, Riverside, Riverside, CA 92521, USA
| | - Jixian Zhai
- Department of Biology and Institute of Plant and Food Science, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Qiang Cui
- Departments of Chemistry, Physics, and Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - Xuehua Zhong
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA.
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI 53715, USA
| | - Jikui Song
- Department of Biochemistry, University of California, Riverside, Riverside, CA 92521, USA.
- Environmental Toxicology Graduate Program, University of California, Riverside, Riverside, CA 92521, USA
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In Response to Abiotic Stress, DNA Methylation Confers EpiGenetic Changes in Plants. PLANTS 2021; 10:plants10061096. [PMID: 34070712 PMCID: PMC8227271 DOI: 10.3390/plants10061096] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/26/2021] [Accepted: 05/27/2021] [Indexed: 02/07/2023]
Abstract
Epigenetics involves the heritable changes in patterns of gene expression determined by developmental and abiotic stresses, i.e., drought, cold, salinity, trace metals, and heat. Gene expression is driven by changes in DNA bases, histone proteins, the biogenesis of ncRNA, and changes in the nucleotide sequence. To cope with abiotic stresses, plants adopt certain changes driven by a sophisticated biological system. DNA methylation is a primary mechanism for epigenetic variation, which can induce phenotypic alterations in plants under stress. Some of the stress-driven changes in plants are temporary, while some modifications may be stable and inheritable to the next generations to allow them to cope with such extreme stress challenges in the future. In this review, we discuss the pivotal role of epigenetically developed phenotypic characteristics in plants as an evolutionary process participating in adaptation and tolerance responses to abiotic and biotic stresses that alter their growth and development. We emphasize the molecular process underlying changes in DNA methylation, differential variation for different species, the roles of non-coding RNAs in epigenetic modification, techniques for studying DNA methylation, and its role in crop improvement in tolerance to abiotic stress (drought, salinity, and heat). We summarize DNA methylation as a significant future research priority for tailoring crops according to various challenging environmental issues.
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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] [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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Chen B, Xu H, Guo Y, Grünhofer P, Schreiber L, Lin J, Li R. Transcriptomic and epigenomic remodeling occurs during vascular cambium periodicity in Populus tomentosa. HORTICULTURE RESEARCH 2021; 8:102. [PMID: 33931595 PMCID: PMC8087784 DOI: 10.1038/s41438-021-00535-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 02/20/2021] [Accepted: 03/08/2021] [Indexed: 05/06/2023]
Abstract
Trees in temperate regions exhibit evident seasonal patterns, which play vital roles in their growth and development. The activity of cambial stem cells is the basis for regulating the quantity and quality of wood, which has received considerable attention. However, the underlying mechanisms of these processes have not been fully elucidated. Here we performed a comprehensive analysis of morphological observations, transcriptome profiles, the DNA methylome, and miRNAs of the cambium in Populus tomentosa during the transition from dormancy to activation. Anatomical analysis showed that the active cambial zone exhibited a significant increase in the width and number of cell layers compared with those of the dormant and reactivating cambium. Furthermore, we found that differentially expressed genes associated with vascular development were mainly involved in plant hormone signal transduction, cell division and expansion, and cell wall biosynthesis. In addition, we identified 235 known miRNAs and 125 novel miRNAs. Differentially expressed miRNAs and target genes showed stronger negative correlations than other miRNA/target pairs. Moreover, global methylation and transcription analysis revealed that CG gene body methylation was positively correlated with gene expression, whereas CHG exhibited the opposite trend in the downstream region. Most importantly, we observed that the number of CHH differentially methylated region (DMR) changes was the greatest during cambium periodicity. Intriguingly, the genes with hypomethylated CHH DMRs in the promoter were involved in plant hormone signal transduction, phenylpropanoid biosynthesis, and plant-pathogen interactions during vascular cambium development. These findings improve our systems-level understanding of the epigenomic diversity that exists in the annual growth cycle of trees.
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Affiliation(s)
- Bo Chen
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China
- Institute of Tree Development and Genome Editing, Beijing Forestry University, Beijing, 100083, China
| | - Huimin Xu
- College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Yayu Guo
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China
- Institute of Tree Development and Genome Editing, Beijing Forestry University, Beijing, 100083, China
| | - Paul Grünhofer
- Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, D-53115, Bonn, Germany
| | - Lukas Schreiber
- Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, D-53115, Bonn, Germany
| | - Jinxing Lin
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China
- Institute of Tree Development and Genome Editing, Beijing Forestry University, Beijing, 100083, China
| | - Ruili Li
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China.
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
- Institute of Tree Development and Genome Editing, Beijing Forestry University, Beijing, 100083, China.
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58
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Perspectives for epigenetic editing in crops. Transgenic Res 2021; 30:381-400. [PMID: 33891288 DOI: 10.1007/s11248-021-00252-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 03/29/2021] [Indexed: 01/10/2023]
Abstract
Site-specific nucleases (SSNs) have drawn much attention in plant biotechnology due to their ability to drive precision mutagenesis, gene targeting or allele replacement. However, when devoid of its nuclease activity, the underlying DNA-binding activity of SSNs can be used to bring other protein functional domains close to specific genomic sites, thus expanding further the range of applications of the technology. In particular, the addition of functional domains encoding epigenetic effectors and chromatin modifiers to the CRISPR/Cas ribonucleoprotein complex opens the possibility to introduce targeted epigenomic modifications in plants in an easily programmable manner. Here we examine some of the most important agronomic traits known to be controlled epigenetically and review the best studied epigenetic catalytic effectors in plants, such as DNA methylases/demethylases or histone acetylases/deacetylases and their associated marks. We also review the most efficient strategies developed to date to functionalize Cas proteins with both catalytic and non-catalytic epigenetic effectors, and the ability of these domains to influence the expression of endogenous genes in a regulatable manner. Based on these new technical developments, we discuss the possibilities offered by epigenetic editing tools in plant biotechnology and their implications in crop breeding.
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59
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Mobility connects: transposable elements wire new transcriptional networks by transferring transcription factor binding motifs. Biochem Soc Trans 2021; 48:1005-1017. [PMID: 32573687 PMCID: PMC7329337 DOI: 10.1042/bst20190937] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 06/01/2020] [Accepted: 06/03/2020] [Indexed: 12/28/2022]
Abstract
Transposable elements (TEs) constitute major fractions of plant genomes. Their potential to be mobile provides them with the capacity to cause major genome rearrangements. Those effects are potentially deleterious and enforced the evolution of epigenetic suppressive mechanisms controlling TE activity. However, beyond their deleterious effects, TE insertions can be neutral or even advantageous for the host, leading to long-term retention of TEs in the host genome. Indeed, TEs are increasingly recognized as major drivers of evolutionary novelties by regulating the expression of nearby genes. TEs frequently contain binding motifs for transcription factors and capture binding motifs during transposition, which they spread through the genome by transposition. Thus, TEs drive the evolution and diversification of gene regulatory networks by recruiting lineage-specific targets under the regulatory control of specific transcription factors. This process can explain the rapid and repeated evolution of developmental novelties, such as C4 photosynthesis and a wide spectrum of stress responses in plants. It also underpins the convergent evolution of embryo nourishing tissues, the placenta in mammals and the endosperm in flowering plants. Furthermore, the gene regulatory network underlying flower development has also been largely reshaped by TE-mediated recruitment of regulatory elements; some of them being preserved across long evolutionary timescales. In this review, we highlight the potential role of TEs as evolutionary toolkits in plants by showcasing examples of TE-mediated evolutionary novelties.
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60
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Wang L, Han W, Diao S, Suo Y, Li H, Mai Y, Wang Y, Sun P, Fu J. Study of Sexual-Linked Genes ( OGI and MeGI) on the Performance of Androecious Persimmons ( Diospyros kaki Thunb.). PLANTS 2021; 10:plants10020390. [PMID: 33670570 PMCID: PMC7922513 DOI: 10.3390/plants10020390] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 02/10/2021] [Accepted: 02/14/2021] [Indexed: 11/25/2022]
Abstract
It is reported that the production of floral sexual phenotype in hexaploid monoecious persimmon (Diospyros kaki) is closely related to a pseudogene called OGI, and a short interspersed nuclear element (SINE)-like insertion (named Kali) in the OGI promoter leads to the gene silence. As a result, DNA methylation level of MeGI promoter determines the development of male or female flowers. However, the molecular mechanism in androecious D. kaki, which only bear male flowers, remains elusive. Here, real-time quantitative polymerase chain reaction (RT-qPCR), molecular cloning, and bisulfite PCR sequencing technique were carried out using 87 materials, including 56 androecious resources, 15 monoecious, and 16 gynoecious cultivars, to investigate the performance of OGI and MeGI on the specific androecious type of D. kaki in China. In conclusion, the Kali insertion was exactly located in the OGI promoter region, and the OGI gene and the Kali sequence were existing and conserved in androecious D. kaki. Meanwhile, we also demonstrated that the MeGI gene was widespread in our investigated samples. Ultimately, our result convincingly provided evidence that the low expression of OGI is probably ascribed to the presence of Kali displaying strong methylation in the OGI promoter, and low expression of MeGI, as well as high DNA methylation level, in the promoter was closely connected with the production of male flowers; this result was consistent with the monoecious persimmon model. Our findings provide predominant genetic aspects for investigation into androecious D. kaki, and future perfecting the sex-determining mechanisms in persimmon.
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Affiliation(s)
- Liyuan Wang
- Key Laboratory of Non-Timber Forest Germplasm Enhancement & Utilization of State Administration of Forestry and Grassland, Non-Timber Forestry Research and Development Center, Chinese Academy of Forestry, Zhengzhou 450003, China; (L.W.); (W.H.); (S.D.); (Y.S.); (H.L.); (Y.M.); (Y.W.)
- Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
| | - Weijuan Han
- Key Laboratory of Non-Timber Forest Germplasm Enhancement & Utilization of State Administration of Forestry and Grassland, Non-Timber Forestry Research and Development Center, Chinese Academy of Forestry, Zhengzhou 450003, China; (L.W.); (W.H.); (S.D.); (Y.S.); (H.L.); (Y.M.); (Y.W.)
| | - Songfeng Diao
- Key Laboratory of Non-Timber Forest Germplasm Enhancement & Utilization of State Administration of Forestry and Grassland, Non-Timber Forestry Research and Development Center, Chinese Academy of Forestry, Zhengzhou 450003, China; (L.W.); (W.H.); (S.D.); (Y.S.); (H.L.); (Y.M.); (Y.W.)
| | - Yujing Suo
- Key Laboratory of Non-Timber Forest Germplasm Enhancement & Utilization of State Administration of Forestry and Grassland, Non-Timber Forestry Research and Development Center, Chinese Academy of Forestry, Zhengzhou 450003, China; (L.W.); (W.H.); (S.D.); (Y.S.); (H.L.); (Y.M.); (Y.W.)
| | - Huawei Li
- Key Laboratory of Non-Timber Forest Germplasm Enhancement & Utilization of State Administration of Forestry and Grassland, Non-Timber Forestry Research and Development Center, Chinese Academy of Forestry, Zhengzhou 450003, China; (L.W.); (W.H.); (S.D.); (Y.S.); (H.L.); (Y.M.); (Y.W.)
| | - Yini Mai
- Key Laboratory of Non-Timber Forest Germplasm Enhancement & Utilization of State Administration of Forestry and Grassland, Non-Timber Forestry Research and Development Center, Chinese Academy of Forestry, Zhengzhou 450003, China; (L.W.); (W.H.); (S.D.); (Y.S.); (H.L.); (Y.M.); (Y.W.)
| | - Yiru Wang
- Key Laboratory of Non-Timber Forest Germplasm Enhancement & Utilization of State Administration of Forestry and Grassland, Non-Timber Forestry Research and Development Center, Chinese Academy of Forestry, Zhengzhou 450003, China; (L.W.); (W.H.); (S.D.); (Y.S.); (H.L.); (Y.M.); (Y.W.)
| | - Peng Sun
- Key Laboratory of Non-Timber Forest Germplasm Enhancement & Utilization of State Administration of Forestry and Grassland, Non-Timber Forestry Research and Development Center, Chinese Academy of Forestry, Zhengzhou 450003, China; (L.W.); (W.H.); (S.D.); (Y.S.); (H.L.); (Y.M.); (Y.W.)
- Correspondence: (P.S.); (J.F.); Tel.: +86-371-65996829 (P.S.); Fax: +86-371-65953628 (P.S.)
| | - Jianmin Fu
- Key Laboratory of Non-Timber Forest Germplasm Enhancement & Utilization of State Administration of Forestry and Grassland, Non-Timber Forestry Research and Development Center, Chinese Academy of Forestry, Zhengzhou 450003, China; (L.W.); (W.H.); (S.D.); (Y.S.); (H.L.); (Y.M.); (Y.W.)
- Correspondence: (P.S.); (J.F.); Tel.: +86-371-65996829 (P.S.); Fax: +86-371-65953628 (P.S.)
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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. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 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] [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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62
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Lu Y, Song Y, Liu L, Wang T. DNA methylation dynamics of sperm cell lineage development in tomato. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:565-579. [PMID: 33249677 DOI: 10.1111/tpj.15098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 11/16/2020] [Accepted: 11/23/2020] [Indexed: 06/12/2023]
Abstract
During the sexual reproduction of higher plants, DNA methylation and transcription are broadly changed to reshape a microspore into two sperm cells (SCs) and a vegetative cell (VC). However, when and how the DNA methylation of SCs is established remains not fully understood. Here we investigate the DNA methylation (5 mC) dynamics of SC lineage and the VC in tomato using whole-genome bisulfite sequencing. We find the asymmetric division of the microspore gives its two daughter cells differential methylome. Compared with the generative cell (GC), the VC is hypomethylated at CG sites while hypermethylated at CHG and CHH sites, with the majority of differentially methylation regions targeted to transposable elements (TEs). SCs have a nearly identical DNA methylome to the GC, suggesting that the methylation landscape in SCs may be pre-established following the asymmetric division or inherited from the GC. The random forest classifier for predicting gene and TE expression shows that methylation within the gene body is a more powerful predictor for gene expression. Among all tested samples, gene and TE expression in the microspore may be more predictable by DNA methylation. Our results depict an intact DNA methylome landscape of SC lineage in higher plants, and reveal that the impact of DNA methylation on transcription is variant in different cell types.
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Affiliation(s)
- Yunlong Lu
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- College of Life Science, University of Chinese Academy of Sciences, Beijing, 100093, China
| | - Yunyun Song
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- College of Life Science, University of Chinese Academy of Sciences, Beijing, 100093, China
| | - Lingtong Liu
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Tai Wang
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- College of Life Science, University of Chinese Academy of Sciences, Beijing, 100093, China
- Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100093, China
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63
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DNA methylation mutants in Physcomitrella patens elucidate individual roles of CG and non-CG methylation in genome regulation. Proc Natl Acad Sci U S A 2020; 117:33700-33710. [PMID: 33376225 DOI: 10.1073/pnas.2011361117] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Cytosine (DNA) methylation in plants regulates the expression of genes and transposons. While methylation in plant genomes occurs at CG, CHG, and CHH sequence contexts, the comparative roles of the individual methylation contexts remain elusive. Here, we present Physcomitrella patens as the second plant system, besides Arabidopsis thaliana, with viable mutants with an essentially complete loss of methylation in the CG and non-CG contexts. In contrast to A. thaliana, P. patens has more robust CHH methylation, similar CG and CHG methylation levels, and minimal cross-talk between CG and non-CG methylation, making it possible to study context-specific effects independently. Our data found CHH methylation to act in redundancy with symmetric methylation in silencing transposons and to regulate the expression of CG/CHG-depleted transposons. Specific elimination of CG methylation did not dysregulate transposons or genes. In contrast, exclusive removal of non-CG methylation massively up-regulated transposons and genes. In addition, comparing two exclusively but equally CG- or CHG-methylated genomes, we show that CHG methylation acts as a greater transcriptional regulator than CG methylation. These results disentangle the transcriptional roles of CG and non-CG, as well as symmetric and asymmetric methylation in a plant genome, and point to the crucial role of non-CG methylation in genome regulation.
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64
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Borges F, Donoghue MTA, LeBlanc C, Wear EE, Tanurdžić M, Berube B, Brooks A, Thompson WF, Hanley-Bowdoin L, Martienssen RA. Loss of Small-RNA-Directed DNA Methylation in the Plant Cell Cycle Promotes Germline Reprogramming and Somaclonal Variation. Curr Biol 2020; 31:591-600.e4. [PMID: 33275892 DOI: 10.1016/j.cub.2020.10.098] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/24/2020] [Accepted: 10/30/2020] [Indexed: 02/07/2023]
Abstract
5-methyl cytosine is widespread in plant genomes in both CG and non-CG contexts. During replication, hemi-methylation on parental DNA strands guides symmetric CG methylation on nascent strands, but non-CG methylation requires modified histones and small RNA guides. Here, we used immortalized Arabidopsis cell suspensions to sort replicating nuclei and determine genome-wide cytosine methylation dynamics during the plant cell cycle. We find that symmetric mCG and mCHG are selectively retained in actively dividing cells in culture, whereas mCHH is depleted. mCG becomes transiently asymmetric during S phase but is rapidly restored in G2, whereas mCHG remains asymmetric throughout the cell cycle. Hundreds of loci gain ectopic CHG methylation, as well as 24-nt small interfering RNAs (siRNAs) and histone H3 lysine dimethylation (H3K9me2), without gaining CHH methylation. This suggests that spontaneous epialleles that arise in plant cell cultures are stably maintained by siRNA and H3K9me2 independent of the canonical RNA-directed DNA methylation (RdDM) pathway. In contrast, loci that fail to produce siRNA may be targeted for demethylation when the cell cycle arrests. Comparative analysis with methylomes of various tissues and cell types suggests that loss of small-RNA-directed non-CG methylation during DNA replication promotes germline reprogramming and epigenetic variation in plants propagated as clones.
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Affiliation(s)
- Filipe Borges
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA; Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France
| | - Mark T A Donoghue
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Chantal LeBlanc
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Emily E Wear
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Milos Tanurdžić
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Benjamin Berube
- Cold Spring Harbor Laboratory School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Ashley Brooks
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - William F Thompson
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Linda Hanley-Bowdoin
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Robert A Martienssen
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.
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65
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Bourguet P, López-González L, Gómez-Zambrano Á, Pélissier T, Hesketh A, Potok ME, Pouch-Pélissier MN, Perez M, Da Ines O, Latrasse D, White CI, Jacobsen SE, Benhamed M, Mathieu O. DNA polymerase epsilon is required for heterochromatin maintenance in Arabidopsis. Genome Biol 2020; 21:283. [PMID: 33234150 PMCID: PMC7687843 DOI: 10.1186/s13059-020-02190-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 10/27/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Chromatin organizes DNA and regulates its transcriptional activity through epigenetic modifications. Heterochromatic regions of the genome are generally transcriptionally silent, while euchromatin is more prone to transcription. During DNA replication, both genetic information and chromatin modifications must be faithfully passed on to daughter strands. There is evidence that DNA polymerases play a role in transcriptional silencing, but the extent of their contribution and how it relates to heterochromatin maintenance is unclear. RESULTS We isolate a strong hypomorphic Arabidopsis thaliana mutant of the POL2A catalytic subunit of DNA polymerase epsilon and show that POL2A is required to stabilize heterochromatin silencing genome-wide, likely by preventing replicative stress. We reveal that POL2A inhibits DNA methylation and histone H3 lysine 9 methylation. Hence, the release of heterochromatin silencing in POL2A-deficient mutants paradoxically occurs in a chromatin context of increased levels of these two repressive epigenetic marks. At the nuclear level, the POL2A defect is associated with fragmentation of heterochromatin. CONCLUSION These results indicate that POL2A is critical to heterochromatin structure and function, and that unhindered replisome progression is required for the faithful propagation of DNA methylation throughout the cell cycle.
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Affiliation(s)
- Pierre Bourguet
- Institute of Genetics Reproduction and Development (iGReD), Université Clermont Auvergne, CNRS, Inserm, F-63000, Clermont-Ferrand, France
| | - Leticia López-González
- Institute of Genetics Reproduction and Development (iGReD), Université Clermont Auvergne, CNRS, Inserm, F-63000, Clermont-Ferrand, France
| | - Ángeles Gómez-Zambrano
- Institute of Genetics Reproduction and Development (iGReD), Université Clermont Auvergne, CNRS, Inserm, F-63000, Clermont-Ferrand, France
- Present Address: Instituto de Bioquímica Vegetal y Fotosíntesis, CSIC-Cartuja, Avda, Américo Vespucio, 49., 41092, Sevilla, Spain
| | - Thierry Pélissier
- Institute of Genetics Reproduction and Development (iGReD), Université Clermont Auvergne, CNRS, Inserm, F-63000, Clermont-Ferrand, France
| | - Amy Hesketh
- Institute of Genetics Reproduction and Development (iGReD), Université Clermont Auvergne, CNRS, Inserm, F-63000, Clermont-Ferrand, France
| | - Magdalena E Potok
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Marie-Noëlle Pouch-Pélissier
- Institute of Genetics Reproduction and Development (iGReD), Université Clermont Auvergne, CNRS, Inserm, F-63000, Clermont-Ferrand, France
| | - Magali Perez
- Institute of Plant Sciences Paris-Saclay (IPS2), CNRS, INRA, University Paris-Sud, University of Evry, University Paris-Diderot, Sorbonne Paris-Cite, University of Paris-Saclay, Batiment, 630, 91405, Orsay, France
| | - Olivier Da Ines
- Institute of Genetics Reproduction and Development (iGReD), Université Clermont Auvergne, CNRS, Inserm, F-63000, Clermont-Ferrand, France
| | - David Latrasse
- Institute of Plant Sciences Paris-Saclay (IPS2), CNRS, INRA, University Paris-Sud, University of Evry, University Paris-Diderot, Sorbonne Paris-Cite, University of Paris-Saclay, Batiment, 630, 91405, Orsay, France
| | - Charles I White
- Institute of Genetics Reproduction and Development (iGReD), Université Clermont Auvergne, CNRS, Inserm, F-63000, Clermont-Ferrand, France
| | - Steven E Jacobsen
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, 90095, USA
- Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Moussa Benhamed
- Institute of Plant Sciences Paris-Saclay (IPS2), CNRS, INRA, University Paris-Sud, University of Evry, University Paris-Diderot, Sorbonne Paris-Cite, University of Paris-Saclay, Batiment, 630, 91405, Orsay, France
| | - Olivier Mathieu
- Institute of Genetics Reproduction and Development (iGReD), Université Clermont Auvergne, CNRS, Inserm, F-63000, Clermont-Ferrand, France.
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66
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Rymen B, Ferrafiat L, Blevins T. Non-coding RNA polymerases that silence transposable elements and reprogram gene expression in plants. Transcription 2020; 11:172-191. [PMID: 33180661 PMCID: PMC7714444 DOI: 10.1080/21541264.2020.1825906] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Multisubunit RNA polymerase (Pol) complexes are the core machinery for gene expression in eukaryotes. The enzymes Pol I, Pol II and Pol III transcribe distinct subsets of nuclear genes. This family of nuclear RNA polymerases expanded in terrestrial plants by the duplication of Pol II subunit genes. Two Pol II-related enzymes, Pol IV and Pol V, are highly specialized in the production of regulatory, non-coding RNAs. Pol IV and Pol V are the central players of RNA-directed DNA methylation (RdDM), an RNA interference pathway that represses transposable elements (TEs) and selected genes. Genetic and biochemical analyses of Pol IV/V subunits are now revealing how these enzymes evolved from ancestral Pol II to sustain non-coding RNA biogenesis in silent chromatin. Intriguingly, Pol IV-RdDM regulates genes that influence flowering time, reproductive development, stress responses and plant–pathogen interactions. Pol IV target genes vary among closely related taxa, indicating that these regulatory circuits are often species-specific. Data from crops like maize, rice, tomato and Brassicarapa suggest that dynamic repositioning of TEs, accompanied by Pol IV targeting to TE-proximal genes, leads to the reprogramming of plant gene expression over short evolutionary timescales.
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Affiliation(s)
- Bart Rymen
- Institut de biologie moléculaire des plantes, Université de Strasbourg , Strasbourg, France
| | - Laura Ferrafiat
- Institut de biologie moléculaire des plantes, Université de Strasbourg , Strasbourg, France
| | - Todd Blevins
- Institut de biologie moléculaire des plantes, Université de Strasbourg , Strasbourg, France
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67
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Tang D, Gallusci P, Lang Z. Fruit development and epigenetic modifications. THE NEW PHYTOLOGIST 2020; 228:839-844. [PMID: 32506476 DOI: 10.1111/nph.16724] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 05/01/2020] [Indexed: 05/26/2023]
Abstract
Fruit development is a complex process that is regulated not only by plant hormones and transcription factors, but also requires epigenetic modifications. Epigenetic modifications include DNA methylation, histone post-translational modifications, chromatin remodeling and noncoding RNAs. Together, these epigenetic modifications, which are controlled during development and in response to the environment, determine the chromatin state of genes and contribute to the transcriptomes of an organism. Recent studies have demonstrated that epigenetic regulation plays an important role in fleshy fruit ripening. Dysfunction of a DNA demethylase delayed ripening in tomato, and the application of a DNA methylation inhibitor altered ripening process in the fruits of several species. These studies indicated that manipulating the epigenome of fruit crops could open new ways for breeding in the future. In this review, we highlight recent progress and address remaining questions and challenges concerning the epigenetic regulation of fruit development and ripening.
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Affiliation(s)
- Dengguo Tang
- Shanghai Center for Plant Stress Biology, National Key Laboratory of Plant Molecular Genetics, Center of Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Philippe Gallusci
- Laboratory of Grape Ecophysiology and Functional Biology, Bordeaux University, INRAE, Bordeaux Science Agro, Villenave d'Ormon, 33140, France
| | - Zhaobo Lang
- Shanghai Center for Plant Stress Biology, National Key Laboratory of Plant Molecular Genetics, Center of Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
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68
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Abstract
RNA-directed DNA methylation (RdDM) is a biological process in which non-coding RNA molecules direct the addition of DNA methylation to specific DNA sequences. The RdDM pathway is unique to plants, although other mechanisms of RNA-directed chromatin modification have also been described in fungi and animals. To date, the RdDM pathway is best characterized within angiosperms (flowering plants), and particularly within the model plant Arabidopsis thaliana. However, conserved RdDM pathway components and associated small RNAs (sRNAs) have also been found in other groups of plants, such as gymnosperms and ferns. The RdDM pathway closely resembles other sRNA pathways, particularly the highly conserved RNAi pathway found in fungi, plants, and animals. Both the RdDM and RNAi pathways produce sRNAs and involve conserved Argonaute, Dicer and RNA-dependent RNA polymerase proteins. RdDM has been implicated in a number of regulatory processes in plants. The DNA methylation added by RdDM is generally associated with transcriptional repression of the genetic sequences targeted by the pathway. Since DNA methylation patterns in plants are heritable, these changes can often be stably transmitted to progeny. As a result, one prominent role of RdDM is the stable, transgenerational suppression of transposable element (TE) activity. RdDM has also been linked to pathogen defense, abiotic stress responses, and the regulation of several key developmental transitions. Although the RdDM pathway has a number of important functions, RdDM-defective mutants in Arabidopsis thaliana are viable and can reproduce, which has enabled detailed genetic studies of the pathway. However, RdDM mutants can have a range of defects in different plant species, including lethality, altered reproductive phenotypes, TE upregulation and genome instability, and increased pathogen sensitivity. Overall, RdDM is an important pathway in plants that regulates a number of processes by establishing and reinforcing specific DNA methylation patterns, which can lead to transgenerational epigenetic effects on gene expression and phenotype.
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69
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Shahryary Y, Symeonidi A, Hazarika RR, Denkena J, Mubeen T, Hofmeister B, van Gurp T, Colomé-Tatché M, Verhoeven KJ, Tuskan G, Schmitz RJ, Johannes F. AlphaBeta: computational inference of epimutation rates and spectra from high-throughput DNA methylation data in plants. Genome Biol 2020; 21:260. [PMID: 33023650 PMCID: PMC7539454 DOI: 10.1186/s13059-020-02161-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 09/02/2020] [Indexed: 01/28/2023] Open
Abstract
Stochastic changes in DNA methylation (i.e., spontaneous epimutations) contribute to methylome diversity in plants. Here, we describe AlphaBeta, a computational method for estimating the precise rate of such stochastic events using pedigree-based DNA methylation data as input. We demonstrate how AlphaBeta can be employed to study transgenerationally heritable epimutations in clonal or sexually derived mutation accumulation lines, as well as somatic epimutations in long-lived perennials. Application of our method to published and new data reveals that spontaneous epimutations accumulate neutrally at the genome-wide scale, originate mainly during somatic development and that they can be used as a molecular clock for age-dating trees.
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Affiliation(s)
- Yadollah Shahryary
- Technical University of Munich, Department of Plant Sciences, Liesel-Beckmann-Str. 2, Freising, 85354 Germany
- Technical University of Munich, Institute for Advanced Study, Lichtenbergstr. 2a, Garching, 85748 Germany
| | - Aikaterini Symeonidi
- Technical University of Munich, Department of Plant Sciences, Liesel-Beckmann-Str. 2, Freising, 85354 Germany
| | - Rashmi R. Hazarika
- Technical University of Munich, Department of Plant Sciences, Liesel-Beckmann-Str. 2, Freising, 85354 Germany
- Technical University of Munich, Institute for Advanced Study, Lichtenbergstr. 2a, Garching, 85748 Germany
| | - Johanna Denkena
- Institute of Computational Biology, Helmholtz Zentrum München, Ingolstädter Landstr. 1, Neuherberg, 85764 Germany
| | - Talha Mubeen
- Technical University of Munich, Department of Plant Sciences, Liesel-Beckmann-Str. 2, Freising, 85354 Germany
- Technical University of Munich, Institute for Advanced Study, Lichtenbergstr. 2a, Garching, 85748 Germany
| | | | - Thomas van Gurp
- Netherlands Institute of Ecology (NIOO-KNAW), Department of Terrestrial Ecology, Wageningen, Wageningen, The Netherlands
| | - Maria Colomé-Tatché
- Institute of Computational Biology, Helmholtz Zentrum München, Ingolstädter Landstr. 1, Neuherberg, 85764 Germany
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, Groningen, 9713 AV Netherlands
- TUM School of Life Sciences Weihenstephan, Technical University of Munich, Emil-Erlenmeyer-Forum 2, Freising, 85354 Germany
| | - Koen J.F. Verhoeven
- Netherlands Institute of Ecology (NIOO-KNAW), Department of Terrestrial Ecology, Wageningen, Wageningen, The Netherlands
| | - Gerald Tuskan
- The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, USA
| | - Robert J. Schmitz
- Technical University of Munich, Institute for Advanced Study, Lichtenbergstr. 2a, Garching, 85748 Germany
- Department of Genetics, The University of Georgia, 120 East Green Street, Athens, 30602 USA
| | - Frank Johannes
- Technical University of Munich, Department of Plant Sciences, Liesel-Beckmann-Str. 2, Freising, 85354 Germany
- Technical University of Munich, Institute for Advanced Study, Lichtenbergstr. 2a, Garching, 85748 Germany
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70
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Papareddy RK, Páldi K, Paulraj S, Kao P, Lutzmayer S, Nodine MD. Chromatin regulates expression of small RNAs to help maintain transposon methylome homeostasis in Arabidopsis. Genome Biol 2020; 21:251. [PMID: 32943088 PMCID: PMC7499886 DOI: 10.1186/s13059-020-02163-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 09/04/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Eukaryotic genomes are partitioned into euchromatic and heterochromatic domains to regulate gene expression and other fundamental cellular processes. However, chromatin is dynamic during growth and development and must be properly re-established after its decondensation. Small interfering RNAs (siRNAs) promote heterochromatin formation, but little is known about how chromatin regulates siRNA expression. RESULTS We demonstrate that thousands of transposable elements (TEs) produce exceptionally high levels of siRNAs in Arabidopsis thaliana embryos. TEs generate siRNAs throughout embryogenesis according to two distinct patterns depending on whether they are located in euchromatic or heterochromatic regions of the genome. siRNA precursors are transcribed in embryos, and siRNAs are required to direct the re-establishment of DNA methylation on TEs from which they are derived in the new generation. Decondensed chromatin also permits the production of 24-nt siRNAs from heterochromatic TEs during post-embryogenesis, and siRNA production from bipartite-classified TEs is controlled by their chromatin states. CONCLUSIONS Decondensation of heterochromatin in response to developmental, and perhaps environmental, cues promotes the transcription and function of siRNAs in plants. Our results indicate that chromatin-mediated siRNA transcription provides a cell-autonomous homeostatic control mechanism to help reconstitute pre-existing chromatin states during growth and development including those that ensure silencing of TEs in the future germ line.
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Affiliation(s)
- Ranjith K. Papareddy
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Katalin Páldi
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Subramanian Paulraj
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Ping Kao
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Stefan Lutzmayer
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Michael D. Nodine
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
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71
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Harris KD, Zemach A. Contiguous and stochastic CHH methylation patterns of plant DRM2 and CMT2 revealed by single-read methylome analysis. Genome Biol 2020; 21:194. [PMID: 32762764 PMCID: PMC7412668 DOI: 10.1186/s13059-020-02099-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Accepted: 07/08/2020] [Indexed: 12/12/2022] Open
Abstract
Cytosine methylome data is commonly generated through next-generation sequencing, with analyses averaging methylation states of individual reads. We propose an alternative method of analysing single-read methylome data. Using this method, we identify patterns relating to the mechanism of two plant non-CG-methylating enzymes, CMT2 and DRM2. CMT2-methylated regions show higher stochasticity, while DRM2-methylated regions have higher variation among cells. Based on these patterns, we develop a classifier that predicts enzyme activity in different species and tissues. To facilitate further single-read analyses, we develop a genome browser, SRBrowse, optimised for visualising and analysing sequencing data at single-read resolution.
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Affiliation(s)
- Keith D Harris
- School of Plant Sciences and Food Security, Tel Aviv University, Haim Levanon, Tel Aviv, Israel
| | - Assaf Zemach
- School of Plant Sciences and Food Security, Tel Aviv University, Haim Levanon, Tel Aviv, Israel.
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72
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Wang G, Li H, Meng S, Yang J, Ye N, Zhang J. Analysis of Global Methylome and Gene Expression during Carbon Reserve Mobilization in Stems under Soil Drying. PLANT PHYSIOLOGY 2020; 183:1809-1824. [PMID: 32513834 PMCID: PMC7401115 DOI: 10.1104/pp.20.00141] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 06/01/2020] [Indexed: 05/18/2023]
Abstract
In rice (Oryza sativa), a specific temporary source organ, the stem, is important for grain filling, and moderate soil drying (MD) enhanced carbon reserve flow from stems to increase grain yield. The dynamics and biological relevance of DNA methylation in carbon reserve remobilization during grain filling are unknown. Here, we generated whole-genome single-base resolution maps of the DNA methylome in the stem. During grain filling under MD, we observed an increase in DNA methylation of total cytosines, with more hypomethylated than hypermethylated regions. Genes responsible for DNA methylation and demethylation were up-regulated, suggesting that DNA methylation changes in the stem were regulated by antagonism between DNA methylation and demethylation activity. In addition, methylation in the CG and CHG contexts was negatively associated with gene expression, while that in the CHH context was positively associated with gene expression. A hypermethylated/up-regulated transcription factor of MYBS2 inhibited MYB30 expression and possibly enhanced β-Amylase5 expression, promoting subsequent starch degradation in rice stems under MD treatment. In addition, a hypermethylated/down-regulated transcription factor of ERF24 was predicted to interact with, and thereby decrease the expression of, abscisic acid 8'-hydroxylase1, thus increasing abscisic acid concentration under MD treatment. Our findings provide insight into the DNA methylation dynamics in carbon reserve remobilization of rice stems, demonstrate that MD increased this remobilization, and suggest a link between DNA methylation and gene expression in rice stems during grain filling.
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Affiliation(s)
- Guanqun Wang
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Shatin 99077, Hong Kong
- Department of Biology, Hong Kong Baptist University, Kowloon 99077, Hong Kong
| | - Haoxuan Li
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Shatin 99077, Hong Kong
- Department of Biology, Hong Kong Baptist University, Kowloon 99077, Hong Kong
| | - Shuan Meng
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha 410128, China
| | - Jianchang Yang
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, Yangzhou University, Yangzhou, Jiangsu 225099, China
| | - Nenghui Ye
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Shatin 99077, Hong Kong
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha 410128, China
| | - Jianhua Zhang
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Shatin 99077, Hong Kong
- Department of Biology, Hong Kong Baptist University, Kowloon 99077, Hong Kong
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73
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Rawoof A, Chhapekar SS, Jaiswal V, Brahma V, Kumar N, Ramchiary N. Single-base cytosine methylation analysis in fruits of three Capsicum species. Genomics 2020; 112:3342-3353. [PMID: 32561348 DOI: 10.1016/j.ygeno.2020.04.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/29/2020] [Accepted: 04/11/2020] [Indexed: 11/30/2022]
Abstract
Single-base cytosine methylation analysis across fruits of Capsicum annuum, C. chinense and C. frutescens showed global average methylation ranging from 82.8-89.1%, 77.6-83.9%, and 22.4-25% at CG, CHG and CHH contexts, respectively. High gene-body methylation at CG and CHG was observed across Capsicum species. The C. annuum showed the highest proportion (>80%) of mCs at different genomic regions compared to C. chinense and C. frutescens. Cytosine methylation for transposable-elements were lower in C. frutescens compared to C. annuum and C. chinense. A total of 510,165 CG, 583112 CHG and 277,897 CHH DMRs were identified across three Capsicum species. The differentially methylated regions (DMRs) distribution analysis revealed C. frutescens as more hypo-methylated compared to C. annuum and C. chinense, and also the presence of more intergenic DMRs in Capsicum genome. At CG and CHG context, gene expression and promoter methylation showed inverse correlations. Furthermore, the observed correlation between methylation and expression of genes suggested the potential role of methylation in Capsicum fruit development/ripening.
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Affiliation(s)
- Abdul Rawoof
- School of Life Sciences, Laboratory of Translational and Evolutionary Genomics, Jawaharlal Nehru University, New Delhi 110067, India
| | - Sushil Satish Chhapekar
- School of Life Sciences, Laboratory of Translational and Evolutionary Genomics, Jawaharlal Nehru University, New Delhi 110067, India
| | - Vandana Jaiswal
- School of Life Sciences, Laboratory of Translational and Evolutionary Genomics, Jawaharlal Nehru University, New Delhi 110067, India; Biotechnology Division, CSIR-Institute of Himalayan Bioresource and Technology, Palampur, Himachal Pradhesh, India
| | - Vijaya Brahma
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Nitin Kumar
- School of Life Sciences, Laboratory of Translational and Evolutionary Genomics, Jawaharlal Nehru University, New Delhi 110067, India; Department of Bioengineering and Technology, Gauhati University, Gopinath Boroloi Nagar, Guwahati 7810014, Assam, India
| | - Nirala Ramchiary
- School of Life Sciences, Laboratory of Translational and Evolutionary Genomics, Jawaharlal Nehru University, New Delhi 110067, India; Department of Biotechnology, Delhi Technological University, Shahbad Daulatpur, Bawana Road, New Delhi 110042, India.
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74
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Small RNA Function in Plants: From Chromatin to the Next Generation. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2020; 84:133-140. [PMID: 32518093 DOI: 10.1101/sqb.2019.84.040394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Small RNA molecules can target a particular virus, gene, or transposable element (TE) with a high degree of specificity. Their ability to move from cell to cell and recognize targets in trans also allows building networks capable of regulating a large number of related targets at once. In the case of epigenetic silencing, small RNA may use the widespread distribution of TEs in eukaryotic genomes to coordinate many loci across developmental and generational time. Here, we discuss the intriguing role of plant small RNA in targeting transposons and repeats in pollen and seeds. Epigenetic reprogramming in the germline and early seed development provides a mechanism to control genome dosage, imprinted gene expression, and incompatible hybridizations via the "triploid block."
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75
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Wang Z, Butel N, Santos-González J, Borges F, Yi J, Martienssen RA, Martinez G, Köhler C. Polymerase IV Plays a Crucial Role in Pollen Development in Capsella. THE PLANT CELL 2020; 32:950-966. [PMID: 31988265 PMCID: PMC7145478 DOI: 10.1105/tpc.19.00938] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/13/2020] [Accepted: 01/21/2020] [Indexed: 05/04/2023]
Abstract
In Arabidopsis (Arabidopsis thaliana), DNA-dependent RNA polymerase IV (Pol IV) is required for the formation of transposable element (TE)-derived small RNA transcripts. These transcripts are processed by DICER-LIKE3 into 24-nucleotide small interfering RNAs (siRNAs) that guide RNA-directed DNA methylation. In the pollen grain, Pol IV is also required for the accumulation of 21/22-nucleotide epigenetically activated siRNAs, which likely silence TEs via post-transcriptional mechanisms. Despite this proposed role of Pol IV, its loss of function in Arabidopsis does not cause a discernible pollen defect. Here, we show that the knockout of NRPD1, encoding the largest subunit of Pol IV, in the Brassicaceae species Capsella (Capsella rubella), caused postmeiotic arrest of pollen development at the microspore stage. As in Arabidopsis, all TE-derived siRNAs were depleted in Capsella nrpd1 microspores. In the wild-type background, the same TEs produced 21/22-nucleotide and 24-nucleotide siRNAs; these processes required Pol IV activity. Arrest of Capsella nrpd1 microspores was accompanied by the deregulation of genes targeted by Pol IV-dependent siRNAs. TEs were much closer to genes in Capsella compared with Arabidopsis, perhaps explaining the essential role of Pol IV in pollen development in Capsella. Our discovery that Pol IV is functionally required in Capsella microspores emphasizes the relevance of investigating different plant models.
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Affiliation(s)
- Zhenxing Wang
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Nicolas Butel
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Juan Santos-González
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Filipe Borges
- Howard Hughes Medical Institute and Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | - Jun Yi
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Robert A Martienssen
- Howard Hughes Medical Institute and Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | - German Martinez
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Claudia Köhler
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
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76
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Chow HT, Chakraborty T, Mosher RA. RNA-directed DNA Methylation and sexual reproduction: expanding beyond the seed. CURRENT OPINION IN PLANT BIOLOGY 2020; 54:11-17. [PMID: 31881293 DOI: 10.1016/j.pbi.2019.11.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 11/20/2019] [Accepted: 11/22/2019] [Indexed: 05/12/2023]
Abstract
Two trends are changing our understanding of RNA-directed DNA methylation. In model systems like Arabidopsis, tissue-specific analysis of DNA methylation is uncovering dynamic changes in methylation during sexual reproduction and unraveling the contribution of maternal and paternal epigenomes to the developing embryo. These studies indicate that RNA-directed DNA Methylation might be important for mediating balance between maternal and paternal contributions to the endosperm. At the same time, researchers are moving beyond Arabidopsis to illuminate the ancestral role of RdDM in non-flowering plants that lack an endosperm, suggesting that RdDM might play a broader role in sexual reproduction.
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Affiliation(s)
- Hiu Tung Chow
- The School of Plant Sciences, The University of Arizona, Tucson, AZ 85721, United States
| | - Tania Chakraborty
- The School of Plant Sciences, The University of Arizona, Tucson, AZ 85721, United States
| | - Rebecca A Mosher
- The School of Plant Sciences, The University of Arizona, Tucson, AZ 85721, United States.
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77
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Wang Z, Baulcombe DC. Transposon age and non-CG methylation. Nat Commun 2020; 11:1221. [PMID: 32144266 PMCID: PMC7060349 DOI: 10.1038/s41467-020-14995-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 02/11/2020] [Indexed: 11/09/2022] Open
Abstract
Silencing of transposable elements (TEs) is established by small RNA-directed DNA methylation (RdDM). Maintenance of silencing is then based on a combination of RdDM and RNA-independent mechanisms involving DNA methyltransferase MET1 and chromodomain DNA methyltransferases (CMTs). Involvement of RdDM, according to this model should decrease with TE age but here we show a different pattern in tomato and Arabidopsis. In these species the CMTs silence long terminal repeat (LTR) transposons in the distal chromatin that are younger than those affected by RdDM. To account for these findings we propose that, after establishment of primary RdDM as in the original model, there is an RNA-independent maintenance phase involving CMTs followed by secondary RdDM. This progression of epigenetic silencing in the gene-rich distal chromatin is likely to influence the transcriptome either in cis or in trans depending on whether the mechanisms are RNA-dependent or -independent. RNA-directed DNA methylation (RdDM) is thought to silence newly inserted transposable elements (TEs) with RNA-independent mechanisms becoming more prominent as TEs age. Here, the authors show that RdDM continues to silence the oldest intact distal TEs in tomato and Arabidopsis suggesting a second, later phase of RdDM.
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Affiliation(s)
- Zhengming Wang
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK
| | - David C Baulcombe
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK.
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78
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Natural variation in DNA methylation homeostasis and the emergence of epialleles. Proc Natl Acad Sci U S A 2020; 117:4874-4884. [PMID: 32071208 DOI: 10.1073/pnas.1918172117] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
In plants and mammals, DNA methylation plays a critical role in transcriptional silencing by delineating heterochromatin from transcriptionally active euchromatin. A homeostatic balance between heterochromatin and euchromatin is essential to genomic stability. This is evident in many diseases and mutants for heterochromatin maintenance, which are characterized by global losses of DNA methylation coupled with localized ectopic gains of DNA methylation that alter transcription. Furthermore, we have shown that genome-wide methylation patterns in Arabidopsis thaliana are highly stable over generations, with the exception of rare epialleles. However, the extent to which natural variation in the robustness of targeting DNA methylation to heterochromatin exists, and the phenotypic consequences of such variation, remain to be fully explored. Here we describe the finding that heterochromatin and genic DNA methylation are highly variable among 725 A. thaliana accessions. We found that genic DNA methylation is inversely correlated with that in heterochromatin, suggesting that certain methylation pathway(s) may be redirected to genes upon the loss of heterochromatin. This redistribution likely involves a feedback loop involving the DNA methyltransferase, CHROMOMETHYLASE 3 (CMT3), H3K9me2, and histone turnover, as highly expressed, long genes with a high density of CMT3-preferred CWG sites are more likely to be methylated. Importantly, although the presence of CG methylation in genes alone may not affect transcription, genes containing CG methylation are more likely to become methylated at non-CG sites and silenced. These findings are consistent with the hypothesis that natural variation in DNA methylation homeostasis may underlie the evolution of epialleles that alter phenotypes.
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79
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Debladis E, Lee TF, Huang YJ, Lu JH, Mathioni SM, Carpentier MC, Llauro C, Pierron D, Mieulet D, Guiderdoni E, Chen PY, Meyers BC, Panaud O, Lasserre E. Construction and characterization of a knock-down RNA interference line of OsNRPD1 in rice ( Oryza sativa ssp japonica cv Nipponbare). Philos Trans R Soc Lond B Biol Sci 2020; 375:20190338. [PMID: 32075556 DOI: 10.1098/rstb.2019.0338] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In plants, RNA-directed DNA methylation (RdDM) is a silencing mechanism relying on the production of 24-nt small interfering RNAs (siRNAs) by RNA POLYMERASE IV (Pol IV) to trigger methylation and inactivation of transposable elements (TEs). We present the construction and characterization of osnrpd1, a knock-down RNA interference line of OsNRPD1 gene that encodes the largest subunit of Pol IV in rice (Oryza sativa ssp japonica cv Nipponbare). We show that osnrpd1 displays a lower accumulation of OsNRPD1 transcripts, associated with an overall reduction of 24-nt siRNAs and DNA methylation level in all three contexts, CG, CHG and CHH. We uncovered new insertions of known active TEs, the LTR retrotransposons Tos17 and Lullaby and the long interspersed nuclear element-type retrotransposon Karma. However, we did not observe any clear developmental phenotype, contrary to what was expected for a mutant severely affected in RdDM. In addition, despite the presence of many putatively functional TEs in the rice genome, we found no evidence of in planta global reactivation of transposition. This knock-down of OsNRPD1 likely led to a weakly affected line, with no effect on development and a limited effect on transposition. We discuss the possibility that a knock-out mutation of OsNRPD1 would cause sterility in rice. This article is part of a discussion meeting issue 'Crossroads between transposons and gene regulation'.
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Affiliation(s)
- Emilie Debladis
- Laboratoire Génome et Développement des Plantes, Université de Perpignan Via Domitia, 52, Avenue Paul alduy, 66860 Perpignan Cedex, France.,Laboratoire Génome et Développement des Plantes, Centre National de la Recherche Scientifique, 52, Avenue Paul alduy, 66860 Perpignan Cedex, France
| | - Tzuu-Fen Lee
- Donald Danforth Plant Science Center, St Louis, MO 63132, USA
| | - Yan-Jiun Huang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Jui-Hsien Lu
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | | | - Marie-Christine Carpentier
- Laboratoire Génome et Développement des Plantes, Université de Perpignan Via Domitia, 52, Avenue Paul alduy, 66860 Perpignan Cedex, France.,Laboratoire Génome et Développement des Plantes, Centre National de la Recherche Scientifique, 52, Avenue Paul alduy, 66860 Perpignan Cedex, France
| | - Christel Llauro
- Laboratoire Génome et Développement des Plantes, Université de Perpignan Via Domitia, 52, Avenue Paul alduy, 66860 Perpignan Cedex, France.,Laboratoire Génome et Développement des Plantes, Centre National de la Recherche Scientifique, 52, Avenue Paul alduy, 66860 Perpignan Cedex, France
| | - Davy Pierron
- Laboratoire Génome et Développement des Plantes, Université de Perpignan Via Domitia, 52, Avenue Paul alduy, 66860 Perpignan Cedex, France.,Laboratoire Génome et Développement des Plantes, Centre National de la Recherche Scientifique, 52, Avenue Paul alduy, 66860 Perpignan Cedex, France
| | | | | | - Pao-Yang Chen
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Blake C Meyers
- Donald Danforth Plant Science Center, St Louis, MO 63132, USA.,Division of Plant Sciences, University of Missouri-Columbia, Columbia, MO 65211, USA
| | - Olivier Panaud
- Laboratoire Génome et Développement des Plantes, Université de Perpignan Via Domitia, 52, Avenue Paul alduy, 66860 Perpignan Cedex, France.,Laboratoire Génome et Développement des Plantes, Centre National de la Recherche Scientifique, 52, Avenue Paul alduy, 66860 Perpignan Cedex, France.,Institut Universitaire de France, Paris, France
| | - Eric Lasserre
- Laboratoire Génome et Développement des Plantes, Université de Perpignan Via Domitia, 52, Avenue Paul alduy, 66860 Perpignan Cedex, France.,Laboratoire Génome et Développement des Plantes, Centre National de la Recherche Scientifique, 52, Avenue Paul alduy, 66860 Perpignan Cedex, France
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80
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Grimanelli D, Ingouff M. DNA Methylation Readers in Plants. J Mol Biol 2020:S0022-2836(20)30027-9. [PMID: 31931004 DOI: 10.1016/j.jmb.2019.12.043] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 12/13/2019] [Accepted: 12/17/2019] [Indexed: 01/09/2023]
Abstract
In plants, DNA methylation occurs in distinct sequence contexts, including CG, CHG, and CHH. Thus, plants have developed a surprisingly diverse set of DNA methylation readers to cope with an extended repertoire of methylated sites. The Arabidopsis genome contains twelve Methyl-Binding Domain proteins (MBD), and nine SET and RING finger-associated (SRA) domain containing proteins belonging to the SUVH clade, in addition to three homologs of UHRF1, namely VIM1-3, all containing SRA domains. In this review, we will highlight several research questions that remain unresolved with respect to the function of plant DNA methylation readers, which can have both de novo demethylase and maintenance activity. We argue that maintenance of CG methylation in plants likely involved actors not found in their mammalian counterparts, and that new evidence suggests significant reprogramming of DNA methylation during plant reproduction as an important new development in the field.
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Affiliation(s)
- Daniel Grimanelli
- Institut de Recherche pour le Développement (IRD), Université de Montpellier, 911 Avenue Agropolis, 34394, Montpellier, France.
| | - Mathieu Ingouff
- Institut de Recherche pour le Développement (IRD), Université de Montpellier, 911 Avenue Agropolis, 34394, Montpellier, France.
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81
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Abstract
Cytosine methylation as a reversible chromatin mark has been investigated extensively for its influence on gene silencing and the regulation of its dynamic association-disassociation at specific sites within a eukaryotic genome. With the remarkable reductions in cost and time associated with whole-genome DNA sequence analysis, coupled with the high fidelity of bisulfite-treated DNA sequencing, single nucleotide resolution of cytosine methylation repatterning within even very large genomes is increasingly achievable. What remains a challenge is the analysis of genome-wide methylome datasets and, consequently, a clear understanding of the overall influence of methylation repatterning on gene expression or vice versa. Reported data have sometimes been subject to stringent data filtering methods that can serve to skew downstream biological interpretation. These complications derive from methylome analysis procedures that vary widely in method and parameter setting. DNA methylation as a chromatin feature that influences DNA stability can be dynamic and rapidly responsive to environmental change. Consequently, methods to discriminate background "noise" of the system from biological signal in response to specific perturbation is essential in some types of experiments. We describe numerous aspects of whole-genome bisulfite sequence data that must be contemplated as well as the various steps of methylome data analysis which impact the biological interpretation of the final output.
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82
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Kenchanmane Raju SK, Ritter EJ, Niederhuth CE. Establishment, maintenance, and biological roles of non-CG methylation in plants. Essays Biochem 2019; 63:743-755. [PMID: 31652316 PMCID: PMC6923318 DOI: 10.1042/ebc20190032] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/18/2019] [Accepted: 09/20/2019] [Indexed: 12/18/2022]
Abstract
Cytosine DNA methylation is prevalent throughout eukaryotes and prokaryotes. While most commonly thought of as being localized to dinucleotide CpG sites, non-CG sites can also be modified. Such non-CG methylation is widespread in plants, occurring at trinucleotide CHG and CHH (H = A, T, or C) sequence contexts. The prevalence of non-CG methylation in plants is due to the plant-specific CHROMOMETHYLASE (CMT) and RNA-directed DNA Methylation (RdDM) pathways. These pathways have evolved through multiple rounds of gene duplication and gene loss, generating epigenomic variation both within and between species. They regulate both transposable elements and genes, ensure genome integrity, and ultimately influence development and environmental responses. In these capacities, non-CG methylation influence and shape plant genomes.
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Affiliation(s)
| | | | - Chad E Niederhuth
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824, U.S.A
- AgBioResearch, Michigan State University, East Lansing, MI 48824, U.S.A
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83
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Yang Y, Tang K, Datsenka TU, Liu W, Lv S, Lang Z, Wang X, Gao J, Wang W, Nie W, Chu Z, Zhang H, Handa AK, Zhu JK, Zhang H. Critical function of DNA methyltransferase 1 in tomato development and regulation of the DNA methylome and transcriptome. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2019; 61:1224-1242. [PMID: 30652405 DOI: 10.1111/jipb.12778] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 01/14/2019] [Indexed: 05/05/2023]
Abstract
DNA methylation confers epigenetic regulation on gene expression and thereby on various biological processes. Tomato has emerged as an excellent system to study the function of DNA methylation in plant development. To date, regulation and function of DNA methylation maintenance remains unclear in tomato plants. Here, we report the critical function of tomato (Solanum lycopersicum) Methyltransferase 1 (SlMET1) in plant development and DNA methylome and transcriptome regulation. Using CRISPR-Cas9 gene editing, we generated slmet1 mutants and observed severe developmental defects with a frame-shift mutation, including small and curly leaves, defective inflorescence, and parthenocarpy. In leaf tissues, mutations in SlMET1 caused CG hypomethylation and CHH hypermethylation on a whole-genome scale, leading to a disturbed transcriptome including ectopic expression of many RIN target genes such as ACC2 in leaf tissues, which are normally expressed in fruits. Neither the CG hypomethylation nor CHH hypermethylation in the slmet1 mutants is related to tissue culture. Meanwhile, tissue culture induces non-CG hypomethylation, which occurs more frequently at gene regions than at TE regions. Our results depict SlMET1- and tissue culture-dependent tomato DNA methylomes, and that SlMET1 is required for maintaining a normal transcriptome and normal development of tomato.
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Affiliation(s)
- Yu Yang
- Shanghai Center for Plant Stress Biology, the Chinese Academy of Sciences, Shanghai, 201602, China
| | - Kai Tang
- Shanghai Center for Plant Stress Biology, the Chinese Academy of Sciences, Shanghai, 201602, China
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, USA
| | - Tatsiana U Datsenka
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, USA
| | - Wenshan Liu
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, USA
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400715, China
| | - Suhui Lv
- Shanghai Center for Plant Stress Biology, the Chinese Academy of Sciences, Shanghai, 201602, China
| | - Zhaobo Lang
- Shanghai Center for Plant Stress Biology, the Chinese Academy of Sciences, Shanghai, 201602, China
| | - Xingang Wang
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, USA
| | - Jinghui Gao
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, USA
- College of Grassland Agriculture, Northwest A&F University, Yangling, 712100, China
| | - Wei Wang
- Shanghai Key Laboratory of Plant Functional Genomics and Resources, Shanghai Chenshan Botanical Garden, Shanghai, 201602, China
- Shanghai Chenshan Plant Science Research Center, the Chinese Academy of Sciences, Shanghai, 201602, China
| | - Wenfeng Nie
- Shanghai Center for Plant Stress Biology, the Chinese Academy of Sciences, Shanghai, 201602, China
| | - Zhaoqing Chu
- Shanghai Key Laboratory of Plant Functional Genomics and Resources, Shanghai Chenshan Botanical Garden, Shanghai, 201602, China
- Shanghai Chenshan Plant Science Research Center, the Chinese Academy of Sciences, Shanghai, 201602, China
| | - Heng Zhang
- Shanghai Center for Plant Stress Biology, the Chinese Academy of Sciences, Shanghai, 201602, China
| | - Avtar K Handa
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, USA
| | - Jian-Kang Zhu
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, USA
- Shanghai Center for Plant Stress Biology, CAS Center of Excellence in Molecular Plant Sciences, the Chinese Academy of Sciences, Shanghai 200032, China
| | - Huiming Zhang
- Shanghai Center for Plant Stress Biology, CAS Center of Excellence in Molecular Plant Sciences, the Chinese Academy of Sciences, Shanghai 200032, China
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84
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de Mendoza A, Lister R, Bogdanovic O. Evolution of DNA Methylome Diversity in Eukaryotes. J Mol Biol 2019:S0022-2836(19)30659-X. [PMID: 31726061 DOI: 10.1016/j.jmb.2019.11.003] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/03/2019] [Accepted: 11/04/2019] [Indexed: 12/23/2022]
Abstract
Cytosine DNA methylation (5mC) is a widespread base modification in eukaryotic genomes with critical roles in transcriptional regulation. In recent years, our understanding of 5mC has changed because of advances in 5mC detection techniques that allow mapping of this mark on the whole genome scale. Profiling DNA methylomes from organisms across the eukaryotic tree of life has reshaped our views on the evolution of 5mC. In this review, we explore the macroevolution of 5mC in major eukaryotic groups, and then focus on recent advances made in animals. Genomic 5mC patterns as well as the mechanisms of 5mC deposition tend to be evolutionary labile across large phylogenetic distances; however, some common patterns are starting to emerge. Within the animal kingdom, 5mC diversity has proven to be much greater than anticipated. For example, a previously held common view that genome hypermethylation is a trait exclusive to vertebrates has recently been challenged. Also, data from genome-wide studies are starting to yield insights into the potential roles of 5mC in invertebrate cis regulation. Here we provide an evolutionary perspective of both the well-known and enigmatic roles of 5mC across the eukaryotic tree of life.
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Affiliation(s)
- Alex de Mendoza
- ARC CoE Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Perth, WA 6009, Australia; Harry Perkins Institute of Medical Research, Perth, WA 6009, Australia.
| | - Ryan Lister
- ARC CoE Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Perth, WA 6009, Australia; Harry Perkins Institute of Medical Research, Perth, WA 6009, Australia
| | - Ozren Bogdanovic
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, NSW 2010, Australia; School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
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85
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Methylation content sensitive enzyme ddRAD (MCSeEd): a reference-free, whole genome profiling system to address cytosine/adenine methylation changes. Sci Rep 2019; 9:14864. [PMID: 31619715 PMCID: PMC6795852 DOI: 10.1038/s41598-019-51423-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 09/26/2019] [Indexed: 12/18/2022] Open
Abstract
Methods for investigating DNA methylation nowadays either require a reference genome and high coverage, or investigate only CG methylation. Moreover, no large-scale analysis can be performed for N6-methyladenosine (6 mA) at an affordable price. Here we describe the methylation content sensitive enzyme double-digest restriction-site-associated DNA (ddRAD) technique (MCSeEd), a reduced-representation, reference-free, cost-effective approach for characterizing whole genome methylation patterns across different methylation contexts (e.g., CG, CHG, CHH, 6 mA). MCSeEd can also detect genetic variations among hundreds of samples. MCSeEd is based on parallel restrictions carried out by combinations of methylation insensitive and sensitive endonucleases, followed by next-generation sequencing. Moreover, we present a robust bioinformatic pipeline (available at https://bitbucket.org/capemaster/mcseed/src/master/ ) for differential methylation analysis combined with single nucleotide polymorphism calling without or with a reference genome.
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86
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Ji L, Mathioni SM, Johnson S, Tucker D, Bewick AJ, Do Kim K, Daron J, Slotkin RK, Jackson SA, Parrott WA, Meyers BC, Schmitz RJ. Genome-Wide Reinforcement of DNA Methylation Occurs during Somatic Embryogenesis in Soybean. THE PLANT CELL 2019; 31:2315-2331. [PMID: 31439802 PMCID: PMC6790092 DOI: 10.1105/tpc.19.00255] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/29/2019] [Accepted: 08/19/2019] [Indexed: 05/06/2023]
Abstract
Somatic embryogenesis is an important tissue culture technique that sometimes leads to phenotypic variation via genetic and/or epigenetic changes. To understand the genomic and epigenomic impacts of somatic embryogenesis, we characterized soybean (Glycine max) epigenomes sampled from embryos at 10 different stages ranging from 6 weeks to 13 years of continuous culture. We identified genome-wide increases in DNA methylation from cultured samples, especially at CHH sites. The hypermethylation almost exclusively occurred in regions previously possessing non-CG methylation and was accompanied by increases in the expression of genes encoding the RNA-directed DNA methylation (RdDM) machinery. The epigenomic changes were similar between somatic and zygotic embryogenesis. Following the initial global wave of hypermethylation, rare decay events of maintenance methylation were observed, and the extent of the decay increased with time in culture. These losses in DNA methylation were accompanied by downregulation of genes encoding the RdDM machinery and transcriptome reprogramming reminiscent of transcriptomes during late-stage seed development. These results reveal a process for reinforcing already silenced regions to maintain genome integrity during somatic embryogenesis over the short term, which eventually decays at certain loci over longer time scales.
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Affiliation(s)
- Lexiang Ji
- Institute of Bioinformatics, University of Georgia, Athens, Georgia 30602
| | | | - Sarah Johnson
- Institute for Plant Breeding Genetics and Genomics, University of Georgia, Athens, Georgia 30602
| | - Donna Tucker
- Institute for Plant Breeding Genetics and Genomics, University of Georgia, Athens, Georgia 30602
| | - Adam J Bewick
- Department of Genetics, University of Georgia, Athens, Georgia 30602
| | - Kyung Do Kim
- Center for Applied Genetic Technologies, University of Georgia, Athens, Georgia 30602
| | - Josquin Daron
- Department of Molecular Genetics, Ohio State University, Columbus, Ohio 43210
| | - R Keith Slotkin
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
- Department of Molecular Genetics, Ohio State University, Columbus, Ohio 43210
| | - Scott A Jackson
- Center for Applied Genetic Technologies, University of Georgia, Athens, Georgia 30602
| | - Wayne A Parrott
- Institute for Plant Breeding Genetics and Genomics, University of Georgia, Athens, Georgia 30602
| | - Blake C Meyers
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
- Division of Plant Sciences, University of Missouri, Columbia, Missouri 63132
| | - Robert J Schmitz
- Department of Genetics, University of Georgia, Athens, Georgia 30602
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87
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Benoit M, Drost HG, Catoni M, Gouil Q, Lopez-Gomollon S, Baulcombe D, Paszkowski J. Environmental and epigenetic regulation of Rider retrotransposons in tomato. PLoS Genet 2019; 15:e1008370. [PMID: 31525177 PMCID: PMC6762207 DOI: 10.1371/journal.pgen.1008370] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 09/26/2019] [Accepted: 08/14/2019] [Indexed: 11/18/2022] Open
Abstract
Transposable elements in crop plants are the powerful drivers of phenotypic variation that has been selected during domestication and breeding programs. In tomato, transpositions of the LTR (long terminal repeat) retrotransposon family Rider have contributed to various phenotypes of agronomical interest, such as fruit shape and colour. However, the mechanisms regulating Rider activity are largely unknown. We have developed a bioinformatics pipeline for the functional annotation of retrotransposons containing LTRs and defined all full-length Rider elements in the tomato genome. Subsequently, we showed that accumulation of Rider transcripts and transposition intermediates in the form of extrachromosomal DNA is triggered by drought stress and relies on abscisic acid signalling. We provide evidence that residual activity of Rider is controlled by epigenetic mechanisms involving siRNAs and the RNA-dependent DNA methylation pathway. Finally, we demonstrate the broad distribution of Rider-like elements in other plant species, including crops. Our work identifies Rider as an environment-responsive element and a potential source of genetic and epigenetic variation in plants. Transposons are major constituents of plant genomes and represent a powerful source of internal genetic and epigenetic variation. For example, domestication of maize has been facilitated by a dramatic change in plant architecture, the consequence of a transposition event. Insertion of transposons near genes often confers quantitative phenotypic variation linked to changes in transcriptional patterns, as documented for blood oranges and grapes. In tomato, the most widely grown fruit crop and model for fleshy fruit biology, occurrences of several beneficial traits related to fruit shape and plant architecture are due to the activity of the transposon family Rider. While Rider represents a unique endogenous source of genetic and epigenetic variation, mechanisms regulating Rider activity remain unexplored. By achieving experimentally-controlled activation of the Rider family, we shed light on the regulation of these transposons by drought stress, signalling by phytohormones, as well as epigenetic pathways. Furthermore, we reveal the presence of Rider-like elements in other economically important crops such as rapeseed, beetroot and quinoa. This suggests that drought-inducible Rider activation could be further harnessed to generate genetic and epigenetic variation for crop breeding, and highlights the potential of transposon-directed mutagenesis for crop improvement.
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Affiliation(s)
- Matthias Benoit
- The Sainsbury Laboratory, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
| | - Hajk-Georg Drost
- The Sainsbury Laboratory, University of Cambridge, Cambridge, United Kingdom
| | - Marco Catoni
- The Sainsbury Laboratory, University of Cambridge, Cambridge, United Kingdom
| | - Quentin Gouil
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Sara Lopez-Gomollon
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - David Baulcombe
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Jerzy Paszkowski
- The Sainsbury Laboratory, University of Cambridge, Cambridge, United Kingdom
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88
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Abstract
DNA methylation is a conserved epigenetic modification that is important for gene regulation and genome stability. Aberrant patterns of DNA methylation can lead to plant developmental abnormalities. A specific DNA methylation state is an outcome of dynamic regulation by de novo methylation, maintenance of methylation and active demethylation, which are catalysed by various enzymes that are targeted by distinct regulatory pathways. In this Review, we discuss DNA methylation in plants, including methylating and demethylating enzymes and regulatory factors, and the coordination of methylation and demethylation activities by a so-called methylstat mechanism; the functions of DNA methylation in regulating transposon silencing, gene expression and chromosome interactions; the roles of DNA methylation in plant development; and the involvement of DNA methylation in plant responses to biotic and abiotic stress conditions.
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89
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Gulyás A, Dobránszki J, Kiss E, da Silva JAT, Posta K, Hidvégi N. Changes in DNA methylation pattern of apple long-term in vitro shoot culture and acclimatized plants. JOURNAL OF PLANT PHYSIOLOGY 2019; 239:18-27. [PMID: 31177027 DOI: 10.1016/j.jplph.2019.05.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 04/17/2019] [Accepted: 05/13/2019] [Indexed: 06/09/2023]
Abstract
DNA methylation is a process of epigenetic modification that can alter the functionality of a genome. Using whole-genome bisulfite sequencing, this study quantify the level of DNA methylation in the epigenomes of two diploid apple (Malus x domestica) scion cultivars ('McIntosh' and 'Húsvéti rozmaring') derived from three environmental conditions: in vivo mother plants in an orchard, in vitro culture, and acclimatized in vitro plants. The global DNA methylation levels were not dependent on the source of plant material, and the average level of DNA methylation was 49.77%, 34.65% and 8.77% in CpG, CHG and CHH contexts, respectively. Significant differences in DNA methylation were identified in 586 (specifically 334, 201 and 131 in CpG, CHG and CHH contexts, respectively) out of 45,116 genes, including promoter and coding sequences. These were classified as differentially methylated genes (DMGs). This is a 1.3% difference in the level of DNA methylation of genes in response to a change in the environment. Differential methylation was visualised by MA plots and functional genomic maps were established for biological processes, molecular functions and cellular components. When the DMGs were considered, in vitro tissue culture resulted in the highest level of methylation, but it was lower in acclimatized in vitro plants which was similar to that in the mother tree. Methylation patterns of the two scions differed, indicating cultivar-specific epigenetic regulation of gene expression during adaptation to various environments. After selecting genes that displayed differences larger than ±10% in CpG and CHG contexts, or larger than ±1.35% in the CHH context from among the DMGs, they were annotated in Blast2 GO v5.1.12 for Gene Ontology. DMGs identified as MD07G1113000 (protein transport), MD08G1041600 (extracellular space), MD09G1054800 (phosphatidic acid binding), and MD10G1265800 (not annotated) were methylated in all three contexts in in vitro shoots. These DNA methylation results suggest that epigenetic changes may contribute to the adaptation of apple to environmental changes by modifying the epigenome and thereby gene expression.
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Affiliation(s)
- Andrea Gulyás
- Research Institute of Nyíregyháza, IAREF, University of Debrecen, Nyíregyháza, P.O. Box 12, H-4400, Hungary.
| | - Judit Dobránszki
- Research Institute of Nyíregyháza, IAREF, University of Debrecen, Nyíregyháza, P.O. Box 12, H-4400, Hungary.
| | - Erzsébet Kiss
- Institute of Genetics, Microbiology and Biotechnology, Faculty of Agricultural and Environmental Sciences, Szent István University, Gödöllő, Páter Károly u.1., H-2100, Hungary.
| | - Jaime A Teixeira da Silva
- Research Institute of Nyíregyháza, IAREF, University of Debrecen, Nyíregyháza, P.O. Box 12, H-4400, Hungary.
| | - Katalin Posta
- Institute of Genetics, Microbiology and Biotechnology, Faculty of Agricultural and Environmental Sciences, Szent István University, Gödöllő, Páter Károly u.1., H-2100, Hungary.
| | - Norbert Hidvégi
- Research Institute of Nyíregyháza, IAREF, University of Debrecen, Nyíregyháza, P.O. Box 12, H-4400, Hungary.
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90
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Wendte JM, Zhang Y, Ji L, Shi X, Hazarika RR, Shahryary Y, Johannes F, Schmitz RJ. Epimutations are associated with CHROMOMETHYLASE 3-induced de novo DNA methylation. eLife 2019; 8:e47891. [PMID: 31356150 PMCID: PMC6663294 DOI: 10.7554/elife.47891] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 07/19/2019] [Indexed: 12/20/2022] Open
Abstract
In many plant species, a subset of transcribed genes are characterized by strictly CG-context DNA methylation, referred to as gene body methylation (gbM). The mechanisms that establish gbM are unclear, yet flowering plant species naturally without gbM lack the DNA methyltransferase, CMT3, which maintains CHG (H = A, C, or T) and not CG methylation at constitutive heterochromatin. Here, we identify the mechanistic basis for gbM establishment by expressing CMT3 in a species naturally lacking CMT3. CMT3 expression reconstituted gbM through a progression of de novo CHG methylation on expressed genes, followed by the accumulation of CG methylation that could be inherited even following loss of the CMT3 transgene. Thus, gbM likely originates from the simultaneous targeting of loci by pathways that promote euchromatin and heterochromatin, which primes genes for the formation of stably inherited epimutations in the form of CG DNA methylation.
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Affiliation(s)
- Jered M Wendte
- Department of GeneticsUniversity of GeorgiaAthensUnited States
| | - Yinwen Zhang
- Institute of BioinformaticsUniversity of GeorgiaAthensUnited States
| | - Lexiang Ji
- Institute of BioinformaticsUniversity of GeorgiaAthensUnited States
| | - Xiuling Shi
- Department of GeneticsUniversity of GeorgiaAthensUnited States
| | - Rashmi R Hazarika
- Department of Plant ScienceTechnical University of MunichFreisingGermany
| | - Yadollah Shahryary
- Department of Plant ScienceTechnical University of MunichFreisingGermany
| | - Frank Johannes
- Department of Plant ScienceTechnical University of MunichFreisingGermany
- Institute for Advanced StudyTechnical University of MunichGarchingGermany
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91
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Wendte JM, Zhang Y, Ji L, Shi X, Hazarika RR, Shahryary Y, Johannes F, Schmitz RJ. Epimutations are associated with CHROMOMETHYLASE 3-induced de novo DNA methylation. eLife 2019. [PMID: 31356150 DOI: 10.7554/elife.47891.037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023] Open
Abstract
In many plant species, a subset of transcribed genes are characterized by strictly CG-context DNA methylation, referred to as gene body methylation (gbM). The mechanisms that establish gbM are unclear, yet flowering plant species naturally without gbM lack the DNA methyltransferase, CMT3, which maintains CHG (H = A, C, or T) and not CG methylation at constitutive heterochromatin. Here, we identify the mechanistic basis for gbM establishment by expressing CMT3 in a species naturally lacking CMT3. CMT3 expression reconstituted gbM through a progression of de novo CHG methylation on expressed genes, followed by the accumulation of CG methylation that could be inherited even following loss of the CMT3 transgene. Thus, gbM likely originates from the simultaneous targeting of loci by pathways that promote euchromatin and heterochromatin, which primes genes for the formation of stably inherited epimutations in the form of CG DNA methylation.
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Affiliation(s)
- Jered M Wendte
- Department of Genetics, University of Georgia, Athens, United States
| | - Yinwen Zhang
- Institute of Bioinformatics, University of Georgia, Athens, United States
| | - Lexiang Ji
- Institute of Bioinformatics, University of Georgia, Athens, United States
| | - Xiuling Shi
- Department of Genetics, University of Georgia, Athens, United States
| | - Rashmi R Hazarika
- Department of Plant Science, Technical University of Munich, Freising, Germany
| | - Yadollah Shahryary
- Department of Plant Science, Technical University of Munich, Freising, Germany
| | - Frank Johannes
- Department of Plant Science, Technical University of Munich, Freising, Germany
- Institute for Advanced Study, Technical University of Munich, Garching, Germany
| | - Robert J Schmitz
- Department of Genetics, University of Georgia, Athens, United States
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92
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Aguilar-Cruz A, Grimanelli D, Haseloff J, Arteaga-Vázquez MA. DNA methylation in Marchantia polymorpha. THE NEW PHYTOLOGIST 2019; 223:575-581. [PMID: 30920664 DOI: 10.1111/nph.15818] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 03/13/2019] [Indexed: 06/09/2023]
Abstract
Methylation of DNA is an epigenetic mechanism for the control of gene expression. Alterations in the regulatory pathways involved in the establishment, perpetuation and removal of DNA methylation can lead to severe developmental alterations. Our understanding of the mechanistic aspects and relevance of DNA methylation comes from remarkable studies in well-established angiosperm plant models including maize and Arabidopsis. The study of plant models positioned at basal lineages opens exciting opportunities to expand our knowledge on the function and evolution of the components of DNA methylation. In this Tansley Insight, we summarize current progress in our understanding of the molecular basis and relevance of DNA methylation in the liverwort Marchantia polymorpha.
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Affiliation(s)
- Adolfo Aguilar-Cruz
- Instituto de Biotecnología y Ecología Aplicada, Universidad Veracruzana, Avenida de las Culturas Veracruzanas 101, Col. Emiliano Zapata, C.P. 91090, Xalapa, Veracruz, México
| | - Daniel Grimanelli
- Institut de Recherche pour le Développement (IRD), UMR232, Université de Montpellier, Montpellier, 34394, France
| | - Jim Haseloff
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK
| | - Mario Alberto Arteaga-Vázquez
- Instituto de Biotecnología y Ecología Aplicada, Universidad Veracruzana, Avenida de las Culturas Veracruzanas 101, Col. Emiliano Zapata, C.P. 91090, Xalapa, Veracruz, México
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93
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RdDM-independent de novo and heterochromatin DNA methylation by plant CMT and DNMT3 orthologs. Nat Commun 2019; 10:1613. [PMID: 30962443 PMCID: PMC6453930 DOI: 10.1038/s41467-019-09496-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Accepted: 03/13/2019] [Indexed: 12/31/2022] Open
Abstract
To properly regulate the genome, cytosine methylation is established by animal DNA methyltransferase 3 s (DNMT3s). While altered DNMT3 homologs, Domains rearranged methyltransferases (DRMs), have been shown to establish methylation via the RNA directed DNA methylation (RdDM) pathway, the role of true-plant DNMT3 orthologs remains elusive. Here, we profile de novo (RPS transgene) and genomic methylation in the basal plant, Physcomitrella patens, mutated in each of its PpDNMTs. We show that PpDNMT3b mediates CG and CHH de novo methylation, independently of PpDRMs. Complementary de novo CHG methylation is specifically mediated by the CHROMOMETHYLASE, PpCMT. Intragenomically, PpDNMT3b functions preferentially within heterochromatin and is affected by PpCMT. In comparison, PpDRMs target active-euchromatic transposons. Overall, our data resolve how DNA methylation in plants can be established in heterochromatin independently of RdDM; suggest that DRMs have emerged to target euchromatin; and link DNMT3 loss in angiosperms to the initiation of heterochromatic CHH methylation by CMT2. Whether plants have true DNMT3 orthologs and their role in establishing DNA methylation are still unclear. Here, the authors show that DNMT3s are persistent through plant evolution and mediates both de novo and heterochromatin DNA methylation in the early divergent land plant Physcomitrella patens.
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94
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Wang L, Shi Y, Chang X, Jing S, Zhang Q, You C, Yuan H, Wang H. DNA methylome analysis provides evidence that the expansion of the tea genome is linked to TE bursts. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:826-835. [PMID: 30256509 PMCID: PMC6419580 DOI: 10.1111/pbi.13018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 09/14/2018] [Accepted: 09/23/2018] [Indexed: 05/12/2023]
Abstract
DNA methylation is essential for gene regulation, imprinting and silencing of transposable elements (TEs). Although bursts of transposable elements are common in many plant lineages, how plant DNA methylation is related to transposon bursts remains unclear. Here we explore the landscape of DNA methylation of tea, a species thought to have experienced a recent transposon burst event. This species possesses more transposable elements than any other sequenced asterids (potato, tomato, coffee, pepper and tobacco). The overall average DNA methylation levels were found to differ among the tea, potato and tomato genomes, and methylation at CHG sequence sites was found to be significantly higher in tea than that in potato or tomato. Moreover, the abundant TEs resulting from burst events not only resulted in tea developing a very large genome size, but also affected many genes involved in importantly biological processes, including caffeine, theanine and flavonoid metabolic pathway genes. In addition, recently transposed TEs were more heavily methylated than ancient ones, implying that DNA methylation is proportionate to the degree of TE silencing, especially on recent active ones. Taken together, our results show that DNA methylation regulates transposon silencing and may play a role in genome size expansion.
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Affiliation(s)
- Lei Wang
- Henan Key Laboratory of Tea Plant BiologyCollege of Life ScienceXinyang Normal UniversityXinyangChina
| | - Yan Shi
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan CropsCollege of Plant ProtectionFujian Agriculture and Forestry UniversityFuzhouChina
| | - Xiaojun Chang
- College of HorticultureFujian Agriculture and Forestry UniversityFuzhouChina
| | - Shengli Jing
- Henan Key Laboratory of Tea Plant BiologyCollege of Life ScienceXinyang Normal UniversityXinyangChina
| | - Qunjie Zhang
- Agrobiological Gene Research CenterGuangdong Academy of Agricultural SciencesGuangzhouChina
| | - Chenjiang You
- Guangdong Provincial Key Laboratory of Plant EpigeneticsCollege of Life Sciences and OceanographyShenzhen UniversityShenzhenChina
- Department of Botany and Plant SciencesInstitute of Integrative Genome BiologyUniversity of CaliforniaRiversideCAUSA
| | - Hongyu Yuan
- Henan Key Laboratory of Tea Plant BiologyCollege of Life ScienceXinyang Normal UniversityXinyangChina
| | - Haifeng Wang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan CropsCollege of Plant ProtectionFujian Agriculture and Forestry UniversityFuzhouChina
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95
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Global increase in DNA methylation during orange fruit development and ripening. Proc Natl Acad Sci U S A 2019; 116:1430-1436. [PMID: 30635417 DOI: 10.1073/pnas.1815441116] [Citation(s) in RCA: 136] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
DNA methylation is an important epigenetic mark involved in many biological processes. The genome of the climacteric tomato fruit undergoes a global loss of DNA methylation due to active DNA demethylation during the ripening process. It is unclear whether the ripening of other fruits is also associated with global DNA demethylation. We characterized the single-base resolution DNA methylomes of sweet orange fruits. Compared with immature orange fruits, ripe orange fruits gained DNA methylation at over 30,000 genomic regions and lost DNA methylation at about 1,000 genomic regions, suggesting a global increase in DNA methylation during orange fruit ripening. This increase in DNA methylation was correlated with decreased expression of DNA demethylase genes. The application of a DNA methylation inhibitor interfered with ripening, indicating that the DNA hypermethylation is critical for the proper ripening of orange fruits. We found that ripening-associated DNA hypermethylation was associated with the repression of several hundred genes, such as photosynthesis genes, and with the activation of hundreds of genes, including genes involved in abscisic acid responses. Our results suggest important roles of DNA methylation in orange fruit ripening.
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96
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Roy Choudhury S. Genome-wide alterations of epigenomic landscape in plants by engineered nanomaterial toxicants. COMPREHENSIVE ANALYTICAL CHEMISTRY 2019. [DOI: 10.1016/bs.coac.2019.04.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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97
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Mechanistic insights into plant SUVH family H3K9 methyltransferases and their binding to context-biased non-CG DNA methylation. Proc Natl Acad Sci U S A 2018; 115:E8793-E8802. [PMID: 30150382 DOI: 10.1073/pnas.1809841115] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
DNA methylation functions in gene silencing and the maintenance of genome integrity. In plants, non-CG DNA methylation is linked through a self-reinforcing loop with histone 3 lysine 9 dimethylation (H3K9me2). The plant-specific SUPPRESSOR OF VARIEGATION 3-9 HOMOLOG (SUVH) family H3K9 methyltransferases (MTases) bind to DNA methylation marks and catalyze H3K9 methylation. Here, we analyzed the structure and function of Arabidopsis thaliana SUVH6 to understand how this class of enzyme maintains methylation patterns in the genome. We reveal that SUVH6 has a distinct 5-methyl-dC (5mC) base-flipping mechanism involving a thumb loop element. Autoinhibition of H3 substrate entry is regulated by a SET domain loop, and a conformational transition in the post-SET domain upon cofactor binding may control catalysis. In vitro DNA binding and in vivo ChIP-seq data reveal that the different SUVH family H3K9 MTases have distinct DNA binding preferences, targeting H3K9 methylation to sites with different methylated DNA sequences, explaining the context biased non-CG DNA methylation in plants.
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98
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Wang Z, Hardcastle TJ, Canto Pastor A, Yip WH, Tang S, Baulcombe DC. A novel DCL2-dependent miRNA pathway in tomato affects susceptibility to RNA viruses. Genes Dev 2018; 32:1155-1160. [PMID: 30150254 PMCID: PMC6120711 DOI: 10.1101/gad.313601.118] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 06/27/2018] [Indexed: 12/19/2022]
Abstract
Wang et al. show that Dicer-like 2 (DCL2) is the major Dicer in tomato defense against tobacco mosaic virus (TMV) and potato virus X (PVX) and that it is involved in the biogenesis of endogenous 22-nt sRNA. Tomato Dicer-like2 (slDCL2) is a key component of resistance pathways against potato virus X (PVX) and tobacco mosaic virus (TMV). It is also required for production of endogenous small RNAs, including miR6026 and other noncanonical microRNAs (miRNAs). The slDCL2 mRNAs are targets of these slDCL2-dependent RNAs in a feedback loop that was disrupted by target mimic RNAs of miR6026. In lines expressing these RNAs, there was correspondingly enhanced resistance against PVX and TMV. These findings illustrate a novel miRNA pathway in plants and a crop protection strategy in which miRNA target mimicry elevates expression of defense-related mRNAs.
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Affiliation(s)
- Zhengming Wang
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, United Kingdom
| | - Thomas J Hardcastle
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, United Kingdom
| | - Alex Canto Pastor
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, United Kingdom
| | - Wing Hin Yip
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong
| | - Shuoya Tang
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, United Kingdom
| | - David C Baulcombe
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, United Kingdom
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99
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Fu FF, Dawe RK, Gent JI. Loss of RNA-Directed DNA Methylation in Maize Chromomethylase and DDM1-Type Nucleosome Remodeler Mutants. THE PLANT CELL 2018; 30:1617-1627. [PMID: 29884624 PMCID: PMC6096594 DOI: 10.1105/tpc.18.00053] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 05/16/2018] [Accepted: 06/07/2018] [Indexed: 05/02/2023]
Abstract
Plants make use of distinct types of DNA methylation characterized by their DNA methyltransferases and modes of regulation. One type, RNA-directed DNA methylation (RdDM), is guided by small interfering RNAs (siRNAs) to the edges of transposons that are close to genes, areas called mCHH islands in maize (Zea mays). Another type, chromomethylation, is guided by histone H3 lysine 9 methylation to heterochromatin across the genome. We examined DNA methylation and small RNA expression in plant tissues that were mutant for both copies of the genes encoding chromomethylases as well as mutants for both copies of the genes encoding DECREASED DNA METHYLATION1 (DDM1)-type nucleosome remodelers, which facilitate chromomethylation. Both sets of double mutants were nonviable but produced embryos and endosperm. RdDM was severely compromised in the double mutant embryos, both in terms of DNA methylation and siRNAs. Loss of 24-nucleotide siRNA from mCHH islands was coupled with a gain of 21-, 22-, and 24-nucleotide siRNAs in heterochromatin. These results reveal a requirement for both chromomethylation and DDM1-type nucleosome remodeling for RdDM in mCHH islands, which we hypothesize is due to dilution of RdDM components across the genome when heterochromatin is compromised.
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Affiliation(s)
- Fang-Fang Fu
- Department of Plant Biology, University of Georgia, Athens, Georgia 30602
| | - R Kelly Dawe
- Department of Plant Biology, University of Georgia, Athens, Georgia 30602
- Department of Genetics, University of Georgia, Athens, Georgia 30602
| | - Jonathan I Gent
- Department of Plant Biology, University of Georgia, Athens, Georgia 30602
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100
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Corem S, Doron-Faigenboim A, Jouffroy O, Maumus F, Arazi T, Bouché N. Redistribution of CHH Methylation and Small Interfering RNAs across the Genome of Tomato ddm1 Mutants. THE PLANT CELL 2018; 30:1628-1644. [PMID: 29875274 PMCID: PMC6096599 DOI: 10.1105/tpc.18.00167] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 05/01/2018] [Accepted: 05/31/2018] [Indexed: 05/18/2023]
Abstract
In plants, cytosine methylation, an epigenetic mark critical for transposon silencing, is maintained over generations by key enzymes that directly methylate DNA and is facilitated by chromatin remodelers, like DECREASE IN DNA METHYLATION1 (DDM1). Short-interfering RNAs (siRNAs) also mediate transposon DNA methylation through a process called RNA-directed DNA methylation (RdDM). In tomato (Solanum lycopersicum), siRNAs are primarily mapped to gene-rich chromosome arms, and not to pericentromeric regions as in Arabidopsis thaliana Tomato encodes two DDM1 genes. To better understand their functions and interaction with the RdDM pathway, we targeted the corresponding genes via the CRISPR/Cas9 technology, resulting in the isolation of Slddm1a and Slddm1b knockout mutants. Unlike the single mutants, Slddm1a Slddm1b double mutant plants display pleiotropic vegetative and reproductive phenotypes, associated with severe hypomethylation of the heterochromatic transposons in both the CG and CHG methylation contexts. The methylation in the CHH context increased for some heterochromatic transposons and conversely decreased for others localized in euchromatin. We found that the number of heterochromatin-associated siRNAs, including RdDM-specific small RNAs, increased significantly, likely limiting the transcriptional reactivation of transposons in Slddm1a Slddm1b Taken together, we propose that the global production of siRNAs and the CHH methylation mediated by the RdDM pathway are restricted to chromosome arms in tomato. Our data suggest that both pathways are greatly enhanced in heterochromatin when DDM1 functions are lost, at the expense of silencing mechanisms normally occurring in euchromatin.
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Affiliation(s)
- Shira Corem
- Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel
| | - Adi Doron-Faigenboim
- Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel
| | | | - Florian Maumus
- URGI, INRA, Université Paris-Saclay, 78000 Versailles, France
| | - Tzahi Arazi
- Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel
| | - Nicolas Bouché
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000 Versailles, France
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