1
|
Osakabe A, Takizawa Y, Horikoshi N, Hatazawa S, Negishi L, Sato S, Berger F, Kakutani T, Kurumizaka H. Molecular and structural basis of the chromatin remodeling activity by Arabidopsis DDM1. Nat Commun 2024; 15:5187. [PMID: 38992002 PMCID: PMC11239853 DOI: 10.1038/s41467-024-49465-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 06/05/2024] [Indexed: 07/13/2024] Open
Abstract
The histone H2A variant H2A.W occupies transposons and thus prevents access to them in Arabidopsis thaliana. H2A.W is deposited by the chromatin remodeler DDM1, which also promotes the accessibility of chromatin writers to heterochromatin by an unknown mechanism. To shed light on this question, we solve the cryo-EM structures of nucleosomes containing H2A and H2A.W, and the DDM1-H2A.W nucleosome complex. These structures show that the DNA end flexibility of the H2A nucleosome is higher than that of the H2A.W nucleosome. In the DDM1-H2A.W nucleosome complex, DDM1 binds to the N-terminal tail of H4 and the nucleosomal DNA and increases the DNA end flexibility of H2A.W nucleosomes. Based on these biochemical and structural results, we propose that DDM1 counters the low accessibility caused by nucleosomes containing H2A.W to enable the maintenance of repressive epigenetic marks on transposons and prevent their activity.
Collapse
Affiliation(s)
- Akihisa Osakabe
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan.
- PRESTO, Japan Science and Technology Agency, Kawaguchi, Japan.
| | - Yoshimasa Takizawa
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
| | - Naoki Horikoshi
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
| | - Suguru Hatazawa
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
| | - Lumi Negishi
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
| | - Shoko Sato
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
| | - Frédéric Berger
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Vienna, Austria
| | - Tetsuji Kakutani
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan.
| | - Hitoshi Kurumizaka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan.
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan.
| |
Collapse
|
2
|
Kakoulidou I, Johannes F. DNA methylation remodeling in F1 hybrids. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:671-681. [PMID: 36752648 DOI: 10.1111/tpj.16137] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/20/2023] [Accepted: 02/05/2023] [Indexed: 06/18/2023]
Abstract
F1 hybrids derived from a cross between two inbred parental lines often display widespread changes in DNA methylation patterns relative to their parents. To which extent these changes drive non-additive gene expression levels and phenotypic heterosis in F1 individuals is not fully resolved. Current mechanistic models propose that DNA methylation remodeling in hybrids is the result of epigenetic interactions between parental alleles via small interfering RNA (sRNA). These models have strong empirical support but are limited to genomic regions where the two parental lines differ in DNA methylation status. However, most remodeling events occur in parental regions with similar methylation patterns, and seem to be strongly conditioned by distally acting factors, even in isogenic hybrid systems. The molecular basis of these distal interactions is currently unknown, and will likely emerge as an active area of research in the future. Despite these gaps in our molecular understanding, parental DNA methylation states are statistically associated with heterosis, independent of genetic information, and may serve as biomarkers in crop breeding.
Collapse
Affiliation(s)
- Ioanna Kakoulidou
- Plant Epigenomics, Technical University of Munich, Emil-Ramman-Str. 4, 85354, Freising, Germany
| | - Frank Johannes
- Plant Epigenomics, Technical University of Munich, Emil-Ramman-Str. 4, 85354, Freising, Germany
| |
Collapse
|
3
|
Gu C, Han R, Liu C, Fang G, Yuan Q, Zheng Z, Yu Q, Jiang J, Liu S, Xie L, Wei H, Zhang Q, Liu G. Heritable epigenetic modification of BpPIN1 is associated with leaf shapes in Betula pendula. TREE PHYSIOLOGY 2023; 43:1811-1824. [PMID: 37406032 DOI: 10.1093/treephys/tpad085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 05/29/2023] [Accepted: 06/29/2023] [Indexed: 07/07/2023]
Abstract
The new variety Betula pendula 'Dalecarlica', selected from Betula pendula, shows high ornamental value owing to its lobed leaf shape. In this study, to identify the genetic components of leaf shape formation, we performed bulked segregant analysis and molecular marker-based fine mapping to identify the causal gene responsible for lobed leaves in B. pendula 'Dalecarlica'. The most significant variations associated with leaf shape were identified within the gene BpPIN1 encoding a member of the PIN-FORMED family, responsible for the auxin efflux carrier. We further confirmed the hypomethylation at the promoter region promoting the expression level of BpPIN1, which causes stronger and longer veins and lobed leaf shape in B. pendula 'Dalecarlica'. These results indicated that DNA methylation at the BpPIN1 promoter region is associated with leaf shapes in B. pendula. Our findings revealed an epigenetic mechanism of BpPIN1 in the regulation of leaf shape in Betula Linn. (birch), which could help in the molecular breeding of ornamental traits.
Collapse
Affiliation(s)
- Chenrui Gu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, No. 51, Hexing Road, Harbin, Heilongjiang 150040, China
| | - Rui Han
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, No. 51, Hexing Road, Harbin, Heilongjiang 150040, China
| | - Chaoyi Liu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, No. 51, Hexing Road, Harbin, Heilongjiang 150040, China
| | - Gonggui Fang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, No. 51, Hexing Road, Harbin, Heilongjiang 150040, China
| | - Qihang Yuan
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, No. 51, Hexing Road, Harbin, Heilongjiang 150040, China
| | - Zhimin Zheng
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, No. 51, Hexing Road, Harbin, Heilongjiang 150040, China
| | - Qibin Yu
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33580, USA
| | - Jing Jiang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, No. 51, Hexing Road, Harbin, Heilongjiang 150040, China
| | - Sanzhen Liu
- Department of Plant Pathology, Kansas State University, Throckmorton Center, 116 Ackert Hall, Manhattan, KS 66506-5502, USA
| | - Linan Xie
- College of Life Science, Northeast Forestry University, No. 26, Hexing Road, Harbin, Heilongjiang 150040, China
| | - Hairong Wei
- College of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Dr, Houghton, MI 49931, USA
| | - Qingzhu Zhang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, No. 51, Hexing Road, Harbin, Heilongjiang 150040, China
- College of Life Science, Northeast Forestry University, No. 26, Hexing Road, Harbin, Heilongjiang 150040, China
| | - Guifeng Liu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, No. 51, Hexing Road, Harbin, Heilongjiang 150040, China
| |
Collapse
|
4
|
Zhou J, Lei X, Shafiq S, Zhang W, Li Q, Li K, Zhu J, Dong Z, He XJ, Sun Q. DDM1-mediated R-loop resolution and H2A.Z exclusion facilitates heterochromatin formation in Arabidopsis. SCIENCE ADVANCES 2023; 9:eadg2699. [PMID: 37566662 PMCID: PMC10421056 DOI: 10.1126/sciadv.adg2699] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 07/13/2023] [Indexed: 08/13/2023]
Abstract
Programmed constitutive heterochromatin silencing is essential for eukaryotic genome regulation, yet the initial step of this process is ambiguous. A large proportion of R-loops (RNA:DNA hybrids) had been unexpectedly identified within Arabidopsis pericentromeric heterochromatin with unknown functions. Through a genome-wide R-loop profiling screen, we find that DDM1 (decrease in DNA methylation 1) is the primary restrictor of pericentromeric R-loops via its RNA:DNA helicase activity. Low levels of pericentromeric R-loops resolved by DDM1 cotranscriptionally can facilitate constitutive heterochromatin silencing. Furthermore, we demonstrate that DDM1 physically excludes histone H2A variant H2A.Z and promotes H2A.W deposition for faithful heterochromatin initiation soon after R-loop clearance. The dual functions of DDM1 in R-loop resolution and H2A.Z eviction are essential for sperm nuclei structure maintenance in mature pollen. Our work unravels the cotranscriptional R-loop resolution coupled with accurate H2A variants deposition is the primary step of constitutive heterochromatin silencing in Arabidopsis, which might be conserved across eukaryotes.
Collapse
Affiliation(s)
- Jincong Zhou
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Xue Lei
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Sarfraz Shafiq
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Weifeng Zhang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Qin Li
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Kuan Li
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Jiafu Zhu
- School of Life Sciences, Guangzhou University, Guangzhou 510006, China
| | - Zhicheng Dong
- School of Life Sciences, Guangzhou University, Guangzhou 510006, China
| | - Xin-jian He
- National Institute of Biological Sciences, Beijing, China
| | - Qianwen Sun
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| |
Collapse
|
5
|
Epigenetic Changes Occurring in Plant Inbreeding. Int J Mol Sci 2023; 24:ijms24065407. [PMID: 36982483 PMCID: PMC10048984 DOI: 10.3390/ijms24065407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/01/2023] [Accepted: 03/10/2023] [Indexed: 03/18/2023] Open
Abstract
Inbreeding is the crossing of closely related individuals in nature or a plantation or self-pollinating plants, which produces plants with high homozygosity. This process can reduce genetic diversity in the offspring and decrease heterozygosity, whereas inbred depression (ID) can often reduce viability. Inbred depression is common in plants and animals and has played a significant role in evolution. In the review, we aim to show that inbreeding can, through the action of epigenetic mechanisms, affect gene expression, resulting in changes in the metabolism and phenotype of organisms. This is particularly important in plant breeding because epigenetic profiles can be linked to the deterioration or improvement of agriculturally important characteristics.
Collapse
|
6
|
Lyons DB, Briffa A, He S, Choi J, Hollwey E, Colicchio J, Anderson I, Feng X, Howard M, Zilberman D. Extensive de novo activity stabilizes epigenetic inheritance of CG methylation in Arabidopsis transposons. Cell Rep 2023; 42:112132. [PMID: 36827183 DOI: 10.1016/j.celrep.2023.112132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 11/10/2022] [Accepted: 02/01/2023] [Indexed: 02/24/2023] Open
Abstract
Cytosine methylation within CG dinucleotides (mCG) can be epigenetically inherited over many generations. Such inheritance is thought to be mediated by a semiconservative mechanism that produces binary present/absent methylation patterns. However, we show here that, in Arabidopsis thaliana h1ddm1 mutants, intermediate heterochromatic mCG is stably inherited across many generations and is quantitatively associated with transposon expression. We develop a mathematical model that estimates the rates of semiconservative maintenance failure and de novo methylation at each transposon, demonstrating that mCG can be stably inherited at any level via a dynamic balance of these activities. We find that DRM2-the core methyltransferase of the RNA-directed DNA methylation pathway-catalyzes most of the heterochromatic de novo mCG, with de novo rates orders of magnitude higher than previously thought, whereas chromomethylases make smaller contributions. Our results demonstrate that stable epigenetic inheritance of mCG in plant heterochromatin is enabled by extensive de novo methylation.
Collapse
Affiliation(s)
| | | | | | | | - Elizabeth Hollwey
- John Innes Centre, Norwich NR4 7UH, UK; Institute of Science and Technology, 3400 Klosterneuburg, Austria
| | - Jack Colicchio
- Department of Plant & Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Ian Anderson
- Department of Plant & Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Xiaoqi Feng
- John Innes Centre, Norwich NR4 7UH, UK; Institute of Science and Technology, 3400 Klosterneuburg, Austria
| | | | - Daniel Zilberman
- John Innes Centre, Norwich NR4 7UH, UK; Institute of Science and Technology, 3400 Klosterneuburg, Austria.
| |
Collapse
|
7
|
Mattei AL, Bailly N, Meissner A. DNA methylation: a historical perspective. Trends Genet 2022; 38:676-707. [DOI: 10.1016/j.tig.2022.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 10/18/2022]
|
8
|
Saradadevi GP, Das D, Mangrauthia SK, Mohapatra S, Chikkaputtaiah C, Roorkiwal M, Solanki M, Sundaram RM, Chirravuri NN, Sakhare AS, Kota S, Varshney RK, Mohannath G. Genetic, Epigenetic, Genomic and Microbial Approaches to Enhance Salt Tolerance of Plants: A Comprehensive Review. BIOLOGY 2021; 10:biology10121255. [PMID: 34943170 PMCID: PMC8698797 DOI: 10.3390/biology10121255] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/23/2021] [Accepted: 11/24/2021] [Indexed: 12/17/2022]
Abstract
Simple Summary Globally, soil salinity, which refers to salt-affected soils, is increasing due to various environmental factors and human activities. Soil salinity poses one of the most serious challenges in the field of agriculture as it significantly reduces the growth and yield of crop plants, both quantitatively and qualitatively. Over the last few decades, several studies have been carried out to understand plant biology in response to soil salinity stress with a major emphasis on genetic and other hereditary components. Based on the outcome of these studies, several approaches are being followed to enhance plants’ ability to tolerate salt stress while still maintaining reasonable levels of crop yields. In this manuscript, we comprehensively list and discuss various biological approaches being followed and, based on the recent advances in the field of molecular biology, we propose some new approaches to improve salinity tolerance of crop plants. The global scientific community can make use of this information for the betterment of crop plants. This review also highlights the importance of maintaining global soil health to prevent several crop plant losses. Abstract Globally, soil salinity has been on the rise owing to various factors that are both human and environmental. The abiotic stress caused by soil salinity has become one of the most damaging abiotic stresses faced by crop plants, resulting in significant yield losses. Salt stress induces physiological and morphological modifications in plants as a result of significant changes in gene expression patterns and signal transduction cascades. In this comprehensive review, with a major focus on recent advances in the field of plant molecular biology, we discuss several approaches to enhance salinity tolerance in plants comprising various classical and advanced genetic and genetic engineering approaches, genomics and genome editing technologies, and plant growth-promoting rhizobacteria (PGPR)-based approaches. Furthermore, based on recent advances in the field of epigenetics, we propose novel approaches to create and exploit heritable genome-wide epigenetic variation in crop plants to enhance salinity tolerance. Specifically, we describe the concepts and the underlying principles of epigenetic recombinant inbred lines (epiRILs) and other epigenetic variants and methods to generate them. The proposed epigenetic approaches also have the potential to create additional genetic variation by modulating meiotic crossover frequency.
Collapse
Affiliation(s)
- Gargi Prasad Saradadevi
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Hyderabad Campus, Hyderabad 500078, India; (G.P.S.); (S.M.)
| | - Debajit Das
- Biological Sciences and Technology Division, CSIR-North East Institute of Science and Technology (CSIR-NEIST), Jorhat 785006, India; (D.D.); (C.C.)
| | - Satendra K. Mangrauthia
- ICAR-Indian Institute of Rice Research, Hyderabad 500030, India; (S.K.M.); (M.S.); (R.M.S.); (N.N.C.); (A.S.S.)
| | - Sridev Mohapatra
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Hyderabad Campus, Hyderabad 500078, India; (G.P.S.); (S.M.)
| | - Channakeshavaiah Chikkaputtaiah
- Biological Sciences and Technology Division, CSIR-North East Institute of Science and Technology (CSIR-NEIST), Jorhat 785006, India; (D.D.); (C.C.)
| | - Manish Roorkiwal
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad 502324, India;
- The UWA Institute of Agriculture, The University of Western Australia, Perth, WA 6009, Australia
| | - Manish Solanki
- ICAR-Indian Institute of Rice Research, Hyderabad 500030, India; (S.K.M.); (M.S.); (R.M.S.); (N.N.C.); (A.S.S.)
| | - Raman Meenakshi Sundaram
- ICAR-Indian Institute of Rice Research, Hyderabad 500030, India; (S.K.M.); (M.S.); (R.M.S.); (N.N.C.); (A.S.S.)
| | - Neeraja N. Chirravuri
- ICAR-Indian Institute of Rice Research, Hyderabad 500030, India; (S.K.M.); (M.S.); (R.M.S.); (N.N.C.); (A.S.S.)
| | - Akshay S. Sakhare
- ICAR-Indian Institute of Rice Research, Hyderabad 500030, India; (S.K.M.); (M.S.); (R.M.S.); (N.N.C.); (A.S.S.)
| | - Suneetha Kota
- ICAR-Indian Institute of Rice Research, Hyderabad 500030, India; (S.K.M.); (M.S.); (R.M.S.); (N.N.C.); (A.S.S.)
- Correspondence: (S.K.); (R.K.V.); (G.M.); Tel.: +91-40-245-91268 (S.K.); +91-84-556-83305 (R.K.V.); +91-40-66303697 (G.M.)
| | - Rajeev K. Varshney
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad 502324, India;
- The UWA Institute of Agriculture, The University of Western Australia, Perth, WA 6009, Australia
- State Agricultural Biotechnology Centre, Centre for Crop and Food Innovation, Food Futures Institute, Murdoch University, Murdoch, WA 6150, Australia
- Correspondence: (S.K.); (R.K.V.); (G.M.); Tel.: +91-40-245-91268 (S.K.); +91-84-556-83305 (R.K.V.); +91-40-66303697 (G.M.)
| | - Gireesha Mohannath
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Hyderabad Campus, Hyderabad 500078, India; (G.P.S.); (S.M.)
- Correspondence: (S.K.); (R.K.V.); (G.M.); Tel.: +91-40-245-91268 (S.K.); +91-84-556-83305 (R.K.V.); +91-40-66303697 (G.M.)
| |
Collapse
|
9
|
Sow MD, Le Gac AL, Fichot R, Lanciano S, Delaunay A, Le Jan I, Lesage-Descauses MC, Citerne S, Caius J, Brunaud V, Soubigou-Taconnat L, Cochard H, Segura V, Chaparro C, Grunau C, Daviaud C, Tost J, Brignolas F, Strauss SH, Mirouze M, Maury S. RNAi suppression of DNA methylation affects the drought stress response and genome integrity in transgenic poplar. THE NEW PHYTOLOGIST 2021; 232:80-97. [PMID: 34128549 DOI: 10.1111/nph.17555] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 06/08/2021] [Indexed: 05/27/2023]
Abstract
Trees are long-lived organisms that continuously adapt to their environments, a process in which epigenetic mechanisms are likely to play a key role. Via downregulation of the chromatin remodeler DECREASED IN DNA METHYLATION 1 (DDM1) in poplar (Populus tremula × Populus alba) RNAi lines, we examined how DNA methylation coordinates genomic and physiological responses to moderate water deficit. We compared the growth and drought response of two RNAi-ddm1 lines to wild-type (WT) trees under well-watered and water deficit/rewatering conditions, and analyzed their methylomes, transcriptomes, mobilomes and phytohormone contents in the shoot apical meristem. The RNAi-ddm1 lines were more tolerant to drought-induced cavitation but did not differ in height or stem diameter growth. About 5000 differentially methylated regions were consistently detected in both RNAi-ddm1 lines, colocalizing with 910 genes and 89 active transposable elements. Under water deficit conditions, 136 differentially expressed genes were found, including many involved in phytohormone pathways; changes in phytohormone concentrations were also detected. Finally, the combination of hypomethylation and drought led to the mobility of two transposable elements. Our findings suggest major roles for DNA methylation in regulation of genes involved in hormone-related stress responses, and the maintenance of genome integrity through repression of transposable elements.
Collapse
Affiliation(s)
- Mamadou D Sow
- LBLGC, INRAE, Université d'Orléans, EA 1207 USC 1328, Orléans, 45067, France
| | - Anne-Laure Le Gac
- LBLGC, INRAE, Université d'Orléans, EA 1207 USC 1328, Orléans, 45067, France
| | - Régis Fichot
- LBLGC, INRAE, Université d'Orléans, EA 1207 USC 1328, Orléans, 45067, France
| | - Sophie Lanciano
- IRD, UMR 232 DIADE, Université de Montpellier, Montpellier, 34090, France
- Laboratory of Plant Genome and Development, Université de Perpignan, Perpignan, 66860, France
| | - Alain Delaunay
- LBLGC, INRAE, Université d'Orléans, EA 1207 USC 1328, Orléans, 45067, France
| | - Isabelle Le Jan
- LBLGC, INRAE, Université d'Orléans, EA 1207 USC 1328, Orléans, 45067, France
| | | | - Sylvie Citerne
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, 78000, France
| | - Jose Caius
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, Orsay, 91405, France
| | - Véronique Brunaud
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, Orsay, 91405, France
| | - Ludivine Soubigou-Taconnat
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, Orsay, 91405, France
| | - Hervé Cochard
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand, 63000, France
| | - Vincent Segura
- BioForA, INRAE, ONF, UMR 0588, Orléans, 45075, France
- UMR AGAP Institut, Université Montpellier, CIRAD, INRAE, Institut Montpellier SupAgro, UMR 1334, Montpellier, F-34398, France
| | | | - Christoph Grunau
- UMR 5244, IHPE, Université de Perpignan, Perpignan, 66100, France
| | - Christian Daviaud
- Laboratory for Epigenetics and Environment Centre National de Recherche en Génomique Humaine, CEA- Institut de Biologie Francois Jacob, Université Paris-Saclay, Evry, 91057, France
| | - Jörg Tost
- Laboratory for Epigenetics and Environment Centre National de Recherche en Génomique Humaine, CEA- Institut de Biologie Francois Jacob, Université Paris-Saclay, Evry, 91057, France
| | - Franck Brignolas
- LBLGC, INRAE, Université d'Orléans, EA 1207 USC 1328, Orléans, 45067, France
| | - Steven H Strauss
- Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, 97331-5752, USA
| | - Marie Mirouze
- IRD, UMR 232 DIADE, Université de Montpellier, Montpellier, 34090, France
- Laboratory of Plant Genome and Development, Université de Perpignan, Perpignan, 66860, France
| | - Stéphane Maury
- LBLGC, INRAE, Université d'Orléans, EA 1207 USC 1328, Orléans, 45067, France
| |
Collapse
|
10
|
Pathway conversion enables a double-lock mechanism to maintain DNA methylation and genome stability. Proc Natl Acad Sci U S A 2021; 118:2107320118. [PMID: 34453006 DOI: 10.1073/pnas.2107320118] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The CMT2 and RNA-directed DNA methylation (RdDM) pathways have been proposed to separately maintain CHH methylation in specific regions of the Arabidopsis thaliana genome. Here, we show that dysfunction of the chromatin remodeler DDM1 causes hundreds of genomic regions to switch from CMT2 dependency to RdDM dependency in DNA methylation. These converted loci are enriched at the edge regions of long transposable elements (TEs). Furthermore, we found that dysfunction in both DDM1 and RdDM causes strong reactivation of TEs and a burst of TE transposition in the first generation of mutant plants, indicating that the DDM1 and RdDM pathways together are critical to maintaining TE repression and protecting genomic stability. Our findings reveal the existence of a pathway conversion-based backup mechanism to guarantee the maintenance of DNA methylation and genome integrity.
Collapse
|
11
|
Gogolev YV, Ahmar S, Akpinar BA, Budak H, Kiryushkin AS, Gorshkov VY, Hensel G, Demchenko KN, Kovalchuk I, Mora-Poblete F, Muslu T, Tsers ID, Yadav NS, Korzun V. OMICs, Epigenetics, and Genome Editing Techniques for Food and Nutritional Security. PLANTS (BASEL, SWITZERLAND) 2021; 10:1423. [PMID: 34371624 PMCID: PMC8309286 DOI: 10.3390/plants10071423] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 06/30/2021] [Accepted: 07/07/2021] [Indexed: 12/22/2022]
Abstract
The incredible success of crop breeding and agricultural innovation in the last century greatly contributed to the Green Revolution, which significantly increased yields and ensures food security, despite the population explosion. However, new challenges such as rapid climate change, deteriorating soil, and the accumulation of pollutants require much faster responses and more effective solutions that cannot be achieved through traditional breeding. Further prospects for increasing the efficiency of agriculture are undoubtedly associated with the inclusion in the breeding strategy of new knowledge obtained using high-throughput technologies and new tools in the future to ensure the design of new plant genomes and predict the desired phenotype. This article provides an overview of the current state of research in these areas, as well as the study of soil and plant microbiomes, and the prospective use of their potential in a new field of microbiome engineering. In terms of genomic and phenomic predictions, we also propose an integrated approach that combines high-density genotyping and high-throughput phenotyping techniques, which can improve the prediction accuracy of quantitative traits in crop species.
Collapse
Affiliation(s)
- Yuri V. Gogolev
- Federal Research Center Kazan Scientific Center of Russian Academy of Sciences, Kazan Institute of Biochemistry and Biophysics, 420111 Kazan, Russia;
- Federal Research Center Kazan Scientific Center of Russian Academy of Sciences, Laboratory of Plant Infectious Diseases, 420111 Kazan, Russia;
| | - Sunny Ahmar
- Institute of Biological Sciences, University of Talca, 1 Poniente 1141, Talca 3460000, Chile; (S.A.); (F.M.-P.)
| | | | - Hikmet Budak
- Montana BioAg Inc., Missoula, MT 59802, USA; (B.A.A.); (H.B.)
| | - Alexey S. Kiryushkin
- Laboratory of Cellular and Molecular Mechanisms of Plant Development, Komarov Botanical Institute of the Russian Academy of Sciences, 197376 Saint Petersburg, Russia; (A.S.K.); (K.N.D.)
| | - Vladimir Y. Gorshkov
- Federal Research Center Kazan Scientific Center of Russian Academy of Sciences, Kazan Institute of Biochemistry and Biophysics, 420111 Kazan, Russia;
- Federal Research Center Kazan Scientific Center of Russian Academy of Sciences, Laboratory of Plant Infectious Diseases, 420111 Kazan, Russia;
| | - Goetz Hensel
- Centre for Plant Genome Engineering, Institute of Plant Biochemistry, Heinrich-Heine-University, 40225 Dusseldorf, Germany;
- Centre of the Region Haná for Biotechnological and Agricultural Research, Czech Advanced Technology and Research Institute, Palacký University Olomouc, 78371 Olomouc, Czech Republic
| | - Kirill N. Demchenko
- Laboratory of Cellular and Molecular Mechanisms of Plant Development, Komarov Botanical Institute of the Russian Academy of Sciences, 197376 Saint Petersburg, Russia; (A.S.K.); (K.N.D.)
| | - Igor Kovalchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada; (I.K.); (N.S.Y.)
| | - Freddy Mora-Poblete
- Institute of Biological Sciences, University of Talca, 1 Poniente 1141, Talca 3460000, Chile; (S.A.); (F.M.-P.)
| | - Tugdem Muslu
- Faculty of Engineering and Natural Sciences, Sabanci University, 34956 Istanbul, Turkey;
| | - Ivan D. Tsers
- Federal Research Center Kazan Scientific Center of Russian Academy of Sciences, Laboratory of Plant Infectious Diseases, 420111 Kazan, Russia;
| | - Narendra Singh Yadav
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada; (I.K.); (N.S.Y.)
| | - Viktor Korzun
- Federal Research Center Kazan Scientific Center of Russian Academy of Sciences, Laboratory of Plant Infectious Diseases, 420111 Kazan, Russia;
- KWS SAAT SE & Co. KGaA, Grimsehlstr. 31, 37555 Einbeck, Germany
| |
Collapse
|
12
|
Stajic D, Jansen LET. Empirical evidence for epigenetic inheritance driving evolutionary adaptation. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200121. [PMID: 33866813 DOI: 10.1098/rstb.2020.0121] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The cellular machinery that regulates gene expression can be self-propagated across cell division cycles and even generations. This renders gene expression states and their associated phenotypes heritable, independently of genetic changes. These phenotypic states, in turn, can be subject to selection and may influence evolutionary adaptation. In this review, we will discuss the molecular basis of epigenetic inheritance, the extent of its transmission and mechanisms of evolutionary adaptation. The current work shows that heritable gene expression can facilitate the process of adaptation through the increase of survival in a novel environment and by enlarging the size of beneficial mutational targets. Moreover, epigenetic control of gene expression enables stochastic switching between different phenotypes in populations that can potentially facilitate adaptation in rapidly fluctuating environments. Ecological studies of the variation of epigenetic markers (e.g. DNA methylation patterns) in wild populations show a potential contribution of this mode of inheritance to local adaptation in nature. However, the extent of the adaptive contribution of the naturally occurring variation in epi-alleles compared to genetic variation remains unclear. This article is part of the theme issue 'How does epigenetics influence the course of evolution?'
Collapse
Affiliation(s)
- Dragan Stajic
- Department of Zoology, University of Stockholm, 106 91 Stockholm, Sweden
| | - Lars E T Jansen
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| |
Collapse
|
13
|
Tyagi V, Parihar V, Singh D, Kapoor S, Kapoor M. The DEAD-box RNA helicase eIF4A1 interacts with the SWI2/SNF2-related chromatin remodelling ATPase DDM1 in the moss Physcomitrella. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1869:140592. [PMID: 33359411 DOI: 10.1016/j.bbapap.2020.140592] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 12/17/2020] [Accepted: 12/18/2020] [Indexed: 12/27/2022]
Abstract
eIF4A is a DEAD box containing RNA helicase that plays crucial roles in regulating translation initiation, growth and abiotic stress tolerance in plants. It also functions as an ATP-dependent RNA binding protein to curb granule formation by limiting RNA-RNA interactions that promote RNA condensation and formation of ribonucleoprotein particles in vivo. Helicase activity of eIF4A is known to be dictated by its binding partners. Proteins interacting with eIF4A have been identified across land plants. In monocots a close link between eIF4A regulated processes and DNA methylation in epigenetic regulation of plant development is inferred from interaction between OseIF4A and the de novo methyltransferase OsDRM2 and loss-of-function studies of these genes in Oryza sativa and Brachypodium distachyon. In the moss Physcomitrella patens, eIF4A1 encoded by Pp3c6_1080V3.1 interacts with the heterogeneous nuclear ribonucleoprotein (hnRNP) PpLIF2L1, homolog of which in Arabidopsis regulates transcription of stress-responsive genes. In this study, using different protein-protein interaction methods, targeted gene knockout strategy and quantitative expression analysis we show genetic interaction between PpeIF4A1 and the putative nucleosome remodeler protein PpDDM1 and between PpDDM1 and PpLIF2L1 in vivo. Stress-induced co-expression of PpeIF4A1, PpDDM1 and PpLIF2L1, their roles in salt stress tolerance and differences in subnuclear distribution of PpLIF2L1 in ppeif4a1 cells in comparison to wild type suggest existence of a regulatory network comprising of RNA helicases, chromatin remodelling proteins and hnRNP active in stress-responsive biological processes in P. patens.
Collapse
Affiliation(s)
- Vidhi Tyagi
- University School of Biotechnology, Guru Gobind Singh Indraprastha University, Sector 16C, Dwarka, New Delhi 110078, India
| | - Vimala Parihar
- University School of Biotechnology, Guru Gobind Singh Indraprastha University, Sector 16C, Dwarka, New Delhi 110078, India
| | - Darshika Singh
- University School of Biotechnology, Guru Gobind Singh Indraprastha University, Sector 16C, Dwarka, New Delhi 110078, India
| | - Sanjay Kapoor
- Interdisciplinary Centre for Plant Genomics and Department of Plant Molecular Biology, University of Delhi, South Campus Benito Juarez Road, New Delhi 110021, India
| | - Meenu Kapoor
- University School of Biotechnology, Guru Gobind Singh Indraprastha University, Sector 16C, Dwarka, New Delhi 110078, India.
| |
Collapse
|
14
|
The Boggarts of biology: how non-genetic changes influence the genotype. Curr Genet 2020; 67:65-77. [PMID: 33037901 DOI: 10.1007/s00294-020-01108-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/14/2020] [Accepted: 09/15/2020] [Indexed: 01/21/2023]
Abstract
The notion that there is a one-one mapping from genotype to phenotype was overturned a long time ago. Along with genotype and environment, 'non-genetic changes' orchestrated by altered RNA and protein molecules also guide the development of phenotype. The idea that there is a route through which changes in phenotype can lead to changes in genotype impinges on several phenomena of molecular, developmental, evolutionary and applied interest. Phenotypic changes that do not alter the underlying DNA sequence have been studied across model systems (eg: DNA and histone modifications, RNA editing, prion formation) and are known to play an important role in short-term adaptation. However, because of their transient nature and unstable inheritance, the role of such changes in long-term evolution has remained controversial. I classify and review three ways in which non-genetic changes can influence genotype and impact cellular fitness across generations, with an emphasis on the enticing idea that they may act as stepping stones for genetic adaptation. I focus on work from microbial systems and attempt to highlight recent experiments and models that bear on this idea. Overall, I review evidence which suggests that non-genetic changes can impact phenotype via their influence on the genotype, and thus play a role in evolutionary change.
Collapse
|
15
|
Parihar V, Dangwal M, Arya D, Kapoor S, Kapoor M. Decrease in DNA methylation 1 interacts with chromomethylase and like heterochromatin protein 1 in
Physcomitrella patens. FEBS Lett 2019; 593:2686-2697. [DOI: 10.1002/1873-3468.13524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 06/22/2019] [Accepted: 06/26/2019] [Indexed: 12/14/2022]
Affiliation(s)
- Vimala Parihar
- University School of Biotechnology Guru Gobind Singh Indraprastha University New Delhi India
| | - Meenakshi Dangwal
- University School of Biotechnology Guru Gobind Singh Indraprastha University New Delhi India
| | - Deepshikha Arya
- University School of Biotechnology Guru Gobind Singh Indraprastha University New Delhi India
| | - Sanjay Kapoor
- University School of Biotechnology Guru Gobind Singh Indraprastha University New Delhi India
- Interdisciplinary Centre for Plant Genomics, Department of Plant Molecular Biology University of Delhi South Campus New Delhi India
| | - Meenu Kapoor
- University School of Biotechnology Guru Gobind Singh Indraprastha University New Delhi India
| |
Collapse
|
16
|
Zhang YY, Latzel V, Fischer M, Bossdorf O. Understanding the evolutionary potential of epigenetic variation: a comparison of heritable phenotypic variation in epiRILs, RILs, and natural ecotypes of Arabidopsis thaliana. Heredity (Edinb) 2018; 121:257-265. [PMID: 29875373 PMCID: PMC6082859 DOI: 10.1038/s41437-018-0095-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 05/08/2018] [Accepted: 05/16/2018] [Indexed: 11/08/2022] Open
Abstract
Increasing evidence for epigenetic variation within and among natural plant populations has led to much speculation about its role in the evolution of plant phenotypes. However, we still have a very limited understanding of the evolutionary potential of epigenetic variation, in particular in comparison to DNA sequence-based variation. To address this question, we compared the magnitudes of heritable phenotypic variation in epigenetic recombinant inbred lines (epiRILs) of Arabidopsis thaliana-lines that mainly differ in DNA methylation but only very little in DNA sequence-with other types of A. thaliana lines that differ strongly also in DNA sequence. We grew subsets of two epiRIL populations with subsets of two genetic RIL populations, of natural ecotype collections, and of lines from a natural population in a common environment and assessed their heritable variation in growth, phenology, and fitness. Among-line phenotypic variation and broad-sense heritabilities tended to be largest in natural ecotypes, but for some traits the variation among epiRILs was comparable to that among RILs and natural ecotypes. Within-line phenotypic variation was generally similar in epiRILs, RILs, and ecotypes. Provided that phenotypic variation in epiRILs is mainly caused by epigenetic differences, whereas in RILs and natural lines it is largely driven by sequence variation, our results indicate that epigenetic variation has the potential to create phenotypic variation that is stable and substantial, and thus of evolutionary significance.
Collapse
Affiliation(s)
- Yuan-Ye Zhang
- Institute of Plant Sciences, University of Bern, CH-3013, Bern, Switzerland.
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361102, China.
| | - Vit Latzel
- Institute of Plant Sciences, University of Bern, CH-3013, Bern, Switzerland
- Institute of Botany of the ASCR, CZ-252 43, Průhonice, Czech Republic
| | - Markus Fischer
- Institute of Plant Sciences, University of Bern, CH-3013, Bern, Switzerland
| | - Oliver Bossdorf
- Institute of Plant Sciences, University of Bern, CH-3013, Bern, Switzerland
- Plant Evolutionary Ecology, University of Tübingen, D-72076, Tübingen, Germany
| |
Collapse
|
17
|
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.
Collapse
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
| |
Collapse
|
18
|
Lauss K, Wardenaar R, Oka R, van Hulten MHA, Guryev V, Keurentjes JJB, Stam M, Johannes F. Parental DNA Methylation States Are Associated with Heterosis in Epigenetic Hybrids. PLANT PHYSIOLOGY 2018; 176:1627-1645. [PMID: 29196538 PMCID: PMC5813580 DOI: 10.1104/pp.17.01054] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 11/14/2017] [Indexed: 05/18/2023]
Abstract
Despite the importance and wide exploitation of heterosis in commercial crop breeding, the molecular mechanisms behind this phenomenon are not completely understood. Recent studies have implicated changes in DNA methylation and small RNAs in hybrid performance; however, it remains unclear whether epigenetic changes are a cause or a consequence of heterosis. Here, we analyze a large panel of over 500 Arabidopsis (Arabidopsis thaliana) epigenetic hybrid plants (epiHybrids), which we derived from near-isogenic but epigenetically divergent parents. This proof-of-principle experimental system allowed us to quantify the contribution of parental methylation differences to heterosis. We measured traits such as leaf area, growth rate, flowering time, main stem branching, rosette branching, and final plant height and observed several strong positive and negative heterotic phenotypes among the epiHybrids. Using an epigenetic quantitative trait locus mapping approach, we were able to identify specific differentially methylated regions in the parental genomes that are associated with hybrid performance. Sequencing of methylomes, transcriptomes, and genomes of selected parent-epiHybrid combinations further showed that these parental differentially methylated regions most likely mediate the remodeling of methylation and transcriptional states at specific loci in the hybrids. Taken together, our data suggest that locus-specific epigenetic divergence between the parental lines can directly or indirectly trigger heterosis in Arabidopsis hybrids independent of genetic changes. These results add to a growing body of evidence that points to epigenetic factors as one of the key determinants of hybrid performance.
Collapse
Affiliation(s)
- Kathrin Lauss
- University of Amsterdam, Swammerdam Institute for Life Sciences, 1098XH Amsterdam, The Netherlands
| | - René Wardenaar
- University of Groningen, Groningen Bioinformatics Centre, Faculty of Mathematics and Natural Sciences, 9747 AG Groningen, The Netherlands
| | - Rurika Oka
- University of Amsterdam, Swammerdam Institute for Life Sciences, 1098XH Amsterdam, The Netherlands
| | - Marieke H A van Hulten
- Wageningen University and Research, Laboratory of Genetics, 6708PB Wageningen, The Netherlands
| | - Victor Guryev
- Genome Structure Aging, European Research Institute for the Biology of Aging, University Medical Centre Groningen and University of Groningen, 9713 AV Groningen, The Netherlands
| | - Joost J B Keurentjes
- Wageningen University and Research, Laboratory of Genetics, 6708PB Wageningen, The Netherlands
| | - Maike Stam
- University of Amsterdam, Swammerdam Institute for Life Sciences, 1098XH Amsterdam, The Netherlands
| | - Frank Johannes
- Population Epigenetics and Epigenomics, Department of Plant Sciences, Technical University of Munich, 85354 Freising, Germany
- Institute for Advanced Study, Technical University of Munich, 85748 Garching, Germany
| |
Collapse
|
19
|
Ramirez-Prado JS, Piquerez SJM, Bendahmane A, Hirt H, Raynaud C, Benhamed M. Modify the Histone to Win the Battle: Chromatin Dynamics in Plant-Pathogen Interactions. FRONTIERS IN PLANT SCIENCE 2018; 9:355. [PMID: 29616066 PMCID: PMC5868138 DOI: 10.3389/fpls.2018.00355] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 03/02/2018] [Indexed: 05/02/2023]
Abstract
Relying on an immune system comes with a high energetic cost for plants. Defense responses in these organisms are therefore highly regulated and fine-tuned, permitting them to respond pertinently to the attack of a microbial pathogen. In recent years, the importance of the physical modification of chromatin, a highly organized structure composed of genomic DNA and its interacting proteins, has become evident in the research field of plant-pathogen interactions. Several processes, including DNA methylation, changes in histone density and variants, and various histone modifications, have been described as regulators of various developmental and defense responses. Herein, we review the state of the art in the epigenomic aspects of plant immunity, focusing on chromatin modifications, chromatin modifiers, and their physiological consequences. In addition, we explore the exciting field of understanding how plant pathogens have adapted to manipulate the plant epigenomic regulation in order to weaken their immune system and thrive in their host, as well as how histone modifications in eukaryotic pathogens are involved in the regulation of their virulence.
Collapse
Affiliation(s)
- Juan S. Ramirez-Prado
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
- Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, University Paris-Sud, University of Évry Val d’Essonne, University Paris Diderot, Sorbonne Paris-Cite, University of Paris-Saclay, UMR9213 Institut des Sciences des Plantes de Paris Saclay, Essonne, France
| | - Sophie J. M. Piquerez
- Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, University Paris-Sud, University of Évry Val d’Essonne, University Paris Diderot, Sorbonne Paris-Cite, University of Paris-Saclay, UMR9213 Institut des Sciences des Plantes de Paris Saclay, Essonne, France
| | - Abdelhafid Bendahmane
- Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, University Paris-Sud, University of Évry Val d’Essonne, University Paris Diderot, Sorbonne Paris-Cite, University of Paris-Saclay, UMR9213 Institut des Sciences des Plantes de Paris Saclay, Essonne, France
| | - Heribert Hirt
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
- Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, University Paris-Sud, University of Évry Val d’Essonne, University Paris Diderot, Sorbonne Paris-Cite, University of Paris-Saclay, UMR9213 Institut des Sciences des Plantes de Paris Saclay, Essonne, France
| | - Cécile Raynaud
- Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, University Paris-Sud, University of Évry Val d’Essonne, University Paris Diderot, Sorbonne Paris-Cite, University of Paris-Saclay, UMR9213 Institut des Sciences des Plantes de Paris Saclay, Essonne, France
| | - Moussa Benhamed
- Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, University Paris-Sud, University of Évry Val d’Essonne, University Paris Diderot, Sorbonne Paris-Cite, University of Paris-Saclay, UMR9213 Institut des Sciences des Plantes de Paris Saclay, Essonne, France
- *Correspondence: Moussa Benhamed,
| |
Collapse
|
20
|
Abstract
While DNA sequence variation is known to be a major driver of phenotypic divergence, epigenetic variation has long been disregarded. One reason for that was the lack of suitable tools. The creation of epigenetically divergent but otherwise largely isogenic Arabidopsis populations has now alleviated some of these constraints. Epigenetic recombinant inbred line (epiRIL) populations allow for examining the effects of epigenetic variation on phenotypes. In addition, epiRILs enabled the development of epigenetic quantitative trait locus (QTLepi) mapping, an approach to identify causal epigenetic factors. Here, we describe the successive steps of QTLepi mapping in a broad sense, from the creation of epigenetically divergent populations to the identification of causal genes underlying particular phenotypes in Arabidopsis.
Collapse
Affiliation(s)
- Kathrin Lauss
- Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098XH, Amsterdam, The Netherlands
| | - Joost J B Keurentjes
- Laboratory of Genetics, Wageningen University and Research, Droevendaalsesteeg 1, 6708PB, Wageningen, The Netherlands.
| |
Collapse
|
21
|
Niederhuth CE, Schmitz RJ. Putting DNA methylation in context: from genomes to gene expression in plants. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2016; 1860:149-156. [PMID: 27590871 DOI: 10.1016/j.bbagrm.2016.08.009] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2016] [Revised: 08/20/2016] [Accepted: 08/23/2016] [Indexed: 12/26/2022]
Abstract
Plant DNA methylation is its own language, interpreted by the cell to maintain silencing of transposons, facilitate chromatin structure, and to ensure proper expression of some genes. Just as in any language, context is important. Rather than being a simple "on-off switch", DNA methylation has a range of "meanings" dependent upon the underlying sequence and its location in the genome. Differences in the sequence context of individual sites are established, maintained, and interpreted by differing molecular pathways. Varying patterns of methylation within genes and surrounding sequences are associated with a continuous range of expression differences, from silencing to constitutive expression. These often-subtle differences have been pieced together from years of effort, but have taken off with the advent of methods for assessing methylation across entire genomes. Recognizing these patterns and identifying underlying causes is essential for understanding the function of DNA methylation and its systems-wide contribution to a range of processes in plant genomes. This article is part of a Special Issue entitled: Plant Gene Regulatory Mechanisms and Networks, edited by Dr. Erich Grotewold and Dr. Nathan Springer.
Collapse
Affiliation(s)
- Chad E Niederhuth
- Department of Genetics, The University of Georgia, Athens, GA, 30602, USA
| | - Robert J Schmitz
- Department of Genetics, The University of Georgia, Athens, GA, 30602, USA.
| |
Collapse
|
22
|
Khan A, Yadav NS, Morgenstern Y, Zemach A, Grafi G. Activation of Tag1 transposable elements in Arabidopsis dedifferentiating cells and their regulation by CHROMOMETHYLASE 3-mediated CHG methylation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2016; 1859:1289-98. [PMID: 27475038 DOI: 10.1016/j.bbagrm.2016.07.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 07/13/2016] [Accepted: 07/25/2016] [Indexed: 12/11/2022]
Abstract
Dedifferentiation, that is, the acquisition of stem cell-like state, commonly induced by stress (e.g., protoplasting), is characterized by open chromatin conformation, a chromatin state that could lead to activation of transposable elements (TEs). Here, we studied the activation of the Arabidopsis class II TE Tag1, in which two copies, situated close to each other (near genes) on chromosome 1 are found in Landsberg erecta (Ler) but not in Columbia (Col). We first transformed protoplasts with a construct in which a truncated Tag1 (ΔTag1 non-autonomous) blocks the expression of a reporter gene AtMBD5-GFP and found a relatively high ectopic excision of ΔTag1 accompanied by expression of AtMBD5-GFP in protoplasts derived from Ler compared to Col; further increase was observed in ddm1 (decrease in DNA methylation1) protoplasts (Ler background). Ectopic excision was associated with transcription of the endogenous Tag1 and changes in histone H3 methylation at the promoter region. Focusing on the endogenous Tag1 elements we found low level of excision in Ler protoplasts, which was slightly and strongly enhanced in ddm1 and cmt3 (chromomethylase3) protoplasts, respectively, concomitantly with reduction in Tag1 gene body (GB) CHG methylation and increased Tag1 transcription; strong activation of Tag1 was also observed in cmt3 leaves. Notably, in cmt3, but not in ddm1, Tag1 elements were excised out from their original sites and transposed elsewhere in the genome. Our results suggest that dedifferentiation is associated with Tag1 activation and that CMT3 rather than DDM1 plays a central role in restraining Tag1 activation via inducing GB CHG methylation.
Collapse
Affiliation(s)
- Asif Khan
- French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion 84990, Israel
| | - Narendra Singh Yadav
- French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion 84990, Israel
| | - Yaakov Morgenstern
- French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion 84990, Israel
| | - Assaf Zemach
- Department of Molecular Biology and Ecology of Plants, Tel-Aviv University, 69978 Tel Aviv, Israel
| | - Gideon Grafi
- French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion 84990, Israel.
| |
Collapse
|
23
|
Lea AJ, Tung J, Zhou X. A Flexible, Efficient Binomial Mixed Model for Identifying Differential DNA Methylation in Bisulfite Sequencing Data. PLoS Genet 2015; 11:e1005650. [PMID: 26599596 PMCID: PMC4657956 DOI: 10.1371/journal.pgen.1005650] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 10/14/2015] [Indexed: 11/26/2022] Open
Abstract
Identifying sources of variation in DNA methylation levels is important for understanding gene regulation. Recently, bisulfite sequencing has become a popular tool for investigating DNA methylation levels. However, modeling bisulfite sequencing data is complicated by dramatic variation in coverage across sites and individual samples, and because of the computational challenges of controlling for genetic covariance in count data. To address these challenges, we present a binomial mixed model and an efficient, sampling-based algorithm (MACAU: Mixed model association for count data via data augmentation) for approximate parameter estimation and p-value computation. This framework allows us to simultaneously account for both the over-dispersed, count-based nature of bisulfite sequencing data, as well as genetic relatedness among individuals. Using simulations and two real data sets (whole genome bisulfite sequencing (WGBS) data from Arabidopsis thaliana and reduced representation bisulfite sequencing (RRBS) data from baboons), we show that our method provides well-calibrated test statistics in the presence of population structure. Further, it improves power to detect differentially methylated sites: in the RRBS data set, MACAU detected 1.6-fold more age-associated CpG sites than a beta-binomial model (the next best approach). Changes in these sites are consistent with known age-related shifts in DNA methylation levels, and are enriched near genes that are differentially expressed with age in the same population. Taken together, our results indicate that MACAU is an efficient, effective tool for analyzing bisulfite sequencing data, with particular salience to analyses of structured populations. MACAU is freely available at www.xzlab.org/software.html.
Collapse
Affiliation(s)
- Amanda J. Lea
- Department of Biology, Duke University, Durham, North Carolina, United States of America
| | - Jenny Tung
- Department of Biology, Duke University, Durham, North Carolina, United States of America
- Institute of Primate Research, National Museums of Kenya, Karen, Nairobi, Kenya
- Department of Evolutionary Anthropology, Duke University, Durham, North Carolina, United States of America
- Duke University Population Research Institute, Duke University, Durham, North Carolina, United States of America
| | - Xiang Zhou
- Department of Biostatistics, University of Michigan, Ann Arbor, Michigan, United States of America
- Center for Statistical Genetics, University of Michigan, Ann Arbor, Michigan, United States of America
| |
Collapse
|
24
|
Wang H, Qi X, Chen S, Fang W, Guan Z, Teng N, Liao Y, Jiang J, Chen F. Limited DNA methylation variation and the transcription of MET1 and DDM1 in the genus Chrysanthemum (Asteraceae): following the track of polyploidy. FRONTIERS IN PLANT SCIENCE 2015; 6:668. [PMID: 26379692 PMCID: PMC4550781 DOI: 10.3389/fpls.2015.00668] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Accepted: 08/13/2015] [Indexed: 05/06/2023]
Abstract
Polyploidy has been recognized as a widespread and common phenomenon among flowering plants. DNA-5'-CCGG site cytosine methylation (C-methylation) is one of the major and immediate epigenetic responses of the plant genome. Elucidating the ways in which altered C-methylation patterns, either at the whole genomic level or at specific sites can affect genome stability in polyploidy will require substantial additional investigation. Methylation sensitive amplification polymorphism profiling was used to evaluate variation in C-methylation among a set of 20 Chrysanthemum species and their close relatives of varying ploidy levels from diploid to decaploid. The range in relative C-methylation level was within 10%, and there was no significant difference neither between different ploidy levels nor between different species in the same ploidy level (U-values < 1.96). The transcript abundances of MET1 and DDM1 genes, which both involved in the regulation of C-methylation at CpG sites, were enhanced with increased ploidy level, but only MET1 was positively correlated with the nuclear DNA content. Considering the key role and efficiency of MET1 in maintaining CpG methylation, the limited variation observed with respect to C-methylation may reflect a balance between the increased activity of MET1 in the higher ploidy genomes and the larger number of CpG dinucleotide sites available for methylation.
Collapse
Affiliation(s)
- Haibin Wang
- College of Horticulture, Nanjing Agricultural UniversityNanjing, China
- Jiangsu Province Engineering Lab for Modern Facility Agriculture Technology and EquipmentNanjing, China
| | - Xiangyu Qi
- College of Horticulture, Nanjing Agricultural UniversityNanjing, China
| | - Sumei Chen
- College of Horticulture, Nanjing Agricultural UniversityNanjing, China
| | - Weimin Fang
- College of Horticulture, Nanjing Agricultural UniversityNanjing, China
| | - Zhiyong Guan
- College of Horticulture, Nanjing Agricultural UniversityNanjing, China
| | - Nianjun Teng
- College of Horticulture, Nanjing Agricultural UniversityNanjing, China
| | - Yuan Liao
- College of Horticulture, Nanjing Agricultural UniversityNanjing, China
| | - Jiafu Jiang
- College of Horticulture, Nanjing Agricultural UniversityNanjing, China
- *Correspondence: Fadi Chen and Jiafu Jiang, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China, ;
| | - Fadi Chen
- College of Horticulture, Nanjing Agricultural UniversityNanjing, China
- Jiangsu Province Engineering Lab for Modern Facility Agriculture Technology and EquipmentNanjing, China
- *Correspondence: Fadi Chen and Jiafu Jiang, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China, ;
| |
Collapse
|
25
|
Costa-Nunes P, Pontes O, Preuss SB, Pikaard CS. Extra views on RNA-dependent DNA methylation and MBD6-dependent heterochromatin formation in nucleolar dominance. Nucleus 2014. [DOI: 10.4161/nucl.11741] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
26
|
Osabe K, Clement JD, Bedon F, Pettolino FA, Ziolkowski L, Llewellyn DJ, Finnegan EJ, Wilson IW. Genetic and DNA methylation changes in cotton (Gossypium) genotypes and tissues. PLoS One 2014; 9:e86049. [PMID: 24465864 PMCID: PMC3896429 DOI: 10.1371/journal.pone.0086049] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 12/05/2013] [Indexed: 12/19/2022] Open
Abstract
In plants, epigenetic regulation is important in normal development and in modulating some agronomic traits. The potential contribution of DNA methylation mediated gene regulation to phenotypic diversity and development in cotton was investigated between cotton genotypes and various tissues. DNA methylation diversity, genetic diversity, and changes in methylation context were investigated using methylation-sensitive amplified polymorphism (MSAP) assays including a methylation insensitive enzyme (BsiSI), and the total DNA methylation level was measured by high-performance liquid chromatography (HPLC). DNA methylation diversity was greater than the genetic diversity in the selected cotton genotypes and significantly different levels of DNA methylation were identified between tissues, including fibre. The higher DNA methylation diversity (CHG methylation being more diverse than CG methylation) in cotton genotypes suggest epigenetic regulation may be important for cotton, and the change in DNA methylation between fibre and other tissues hints that some genes may be epigenetically regulated for fibre development. The novel approach using BsiSI allowed direct comparison between genetic and epigenetic diversity, and also measured CC methylation level that cannot be detected by conventional MSAP.
Collapse
|
27
|
Grafi G, Ohad N. Plant Epigenetics: A Historical Perspective. EPIGENETIC MEMORY AND CONTROL IN PLANTS 2013. [DOI: 10.1007/978-3-642-35227-0_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
28
|
Latzel V, Zhang Y, Karlsson Moritz K, Fischer M, Bossdorf O. Epigenetic variation in plant responses to defence hormones. ANNALS OF BOTANY 2012; 110:1423-8. [PMID: 22543179 PMCID: PMC3489142 DOI: 10.1093/aob/mcs088] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Accepted: 02/22/2012] [Indexed: 05/23/2023]
Abstract
BACKGROUND AND AIMS There is currently much speculation about the role of epigenetic variation as a determinant of heritable variation in ecologically important plant traits. However, we still know very little about the phenotypic consequences of epigenetic variation, in particular with regard to more complex traits related to biotic interactions. METHODS Here, a test was carried out to determine whether variation in DNA methylation alone can cause heritable variation in plant growth responses to jasmonic acid and salicylic acid, two key hormones involved in induction of plant defences against herbivores and pathogens. In order to be able to ascribe phenotypic differences to epigenetic variation, the hormone responses were studied of epigenetic recombinant inbred lines (epiRILs) of Arabidopsis thaliana - lines that are highly variable at the level of DNA methylation but nearly identical at the level of DNA sequence. KEY RESULTS Significant heritable variation was found among epiRILs both in the means of phenotypic traits, including growth rate, and in the degree to which these responded to treatment with jasmonic acid and salicylic acid. Moreover, there was a positive epigenetic correlation between the responses of different epiRILs to the two hormones, suggesting that plant responses to herbivore and pathogen attack may have a similar molecular epigenetic basis. CONCLUSIONS This study demonstrates that epigenetic variation alone can cause heritable variation in, and thus potentially microevolution of, plant responses to defence hormones. This suggests that part of the variation of plant defences observed in natural populations may be due to underlying epigenetic, rather than entirely genetic, variation.
Collapse
Affiliation(s)
- Vít Latzel
- Institute of Plant Sciences, University of Bern, Switzerland.
| | | | | | | | | |
Collapse
|
29
|
Amoah S, Kurup S, Rodriguez Lopez CM, Welham SJ, Powers SJ, Hopkins CJ, Wilkinson MJ, King GJ. A hypomethylated population of Brassica rapa for forward and reverse epi-genetics. BMC PLANT BIOLOGY 2012; 12:193. [PMID: 23082790 DOI: 10.1186/1471-2229-12-] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 10/09/2012] [Indexed: 05/28/2023]
Abstract
BACKGROUND Epigenetic marks superimposed on the DNA sequence of eukaryote chromosomes provide agility and plasticity in terms of modulating gene expression, ontology, and response to the environment. Modulating the methylation status of cytosine can generate epialleles, which have been detected and characterised at specific loci in several plant systems, and have the potential to generate novel and relatively stable phenotypes. There have been no systematic attempts to explore and utilise epiallelic variation, and so extend the range of phenotypes available for selection in crop improvement. We developed an approach for generating novel epialleles by perturbation of the DNA methylation status. 5- Azacytidine (5-AzaC) provides selective targeting of 5 mCG, which in plants is associated with exonic DNA. Targeted chemical intervention using 5-AzaC has advantages over transgenic or mutant modulation of methyltransferases, allowing stochastic generation of epialleles across the genome. RESULTS We demonstrate the potential of stochastic chemically-induced hypomethylation to generate novel and valuable variation for crop improvement. Systematic analysis of dose-response to 5-AzaC in B. rapa guided generation of a selfed stochastically hypomethylated population, used for forward screening of several agronomic traits. Dose-response was sigmoidal for several traits, similar to that observed for chemical mutagens such as EMS. We demonstrated transgenerational inheritance of some phenotypes. BraRoAZ is a unique hypomethylated population of 1000 E2 sib lines. When compared to untreated controls, 5-Aza C-treated lines exhibited reduced immuno-staining of 5mC on pachytene chromosomes, and Methylation Sensitive Amplified Polymorphism (MSAP) profiles that were both divergent and more variable. There was coincident phenotypic variation among these lines for a range of seed yield and composition traits, including increased seed protein content and decreased oil content, as well as decreased erucic acid and corresponding increases in linoleic and/or palmitic acid. Each 5-AzaC-treated line represents a unique combination of hypomethylated epialleles. CONCLUSIONS The approach and populations developed are available for forward and reverse screening of epiallelic variation and subsequent functional and inheritance studies. The generation of stochastically hypomethylated populations has utility in epiallele discovery for a wide range of crop plants, and has considerable potential as an intervention strategy for crop improvement.
Collapse
|
30
|
Amoah S, Kurup S, Rodriguez Lopez CM, Welham SJ, Powers SJ, Hopkins CJ, Wilkinson MJ, King GJ. A hypomethylated population of Brassica rapa for forward and reverse epi-genetics. BMC PLANT BIOLOGY 2012; 12:193. [PMID: 23082790 PMCID: PMC3507869 DOI: 10.1186/1471-2229-12-193] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 10/09/2012] [Indexed: 05/22/2023]
Abstract
BACKGROUND Epigenetic marks superimposed on the DNA sequence of eukaryote chromosomes provide agility and plasticity in terms of modulating gene expression, ontology, and response to the environment. Modulating the methylation status of cytosine can generate epialleles, which have been detected and characterised at specific loci in several plant systems, and have the potential to generate novel and relatively stable phenotypes. There have been no systematic attempts to explore and utilise epiallelic variation, and so extend the range of phenotypes available for selection in crop improvement. We developed an approach for generating novel epialleles by perturbation of the DNA methylation status. 5- Azacytidine (5-AzaC) provides selective targeting of 5 mCG, which in plants is associated with exonic DNA. Targeted chemical intervention using 5-AzaC has advantages over transgenic or mutant modulation of methyltransferases, allowing stochastic generation of epialleles across the genome. RESULTS We demonstrate the potential of stochastic chemically-induced hypomethylation to generate novel and valuable variation for crop improvement. Systematic analysis of dose-response to 5-AzaC in B. rapa guided generation of a selfed stochastically hypomethylated population, used for forward screening of several agronomic traits. Dose-response was sigmoidal for several traits, similar to that observed for chemical mutagens such as EMS. We demonstrated transgenerational inheritance of some phenotypes. BraRoAZ is a unique hypomethylated population of 1000 E2 sib lines. When compared to untreated controls, 5-Aza C-treated lines exhibited reduced immuno-staining of 5mC on pachytene chromosomes, and Methylation Sensitive Amplified Polymorphism (MSAP) profiles that were both divergent and more variable. There was coincident phenotypic variation among these lines for a range of seed yield and composition traits, including increased seed protein content and decreased oil content, as well as decreased erucic acid and corresponding increases in linoleic and/or palmitic acid. Each 5-AzaC-treated line represents a unique combination of hypomethylated epialleles. CONCLUSIONS The approach and populations developed are available for forward and reverse screening of epiallelic variation and subsequent functional and inheritance studies. The generation of stochastically hypomethylated populations has utility in epiallele discovery for a wide range of crop plants, and has considerable potential as an intervention strategy for crop improvement.
Collapse
Affiliation(s)
| | - Smita Kurup
- Rothamsted Research, Harpenden, Herts AL5 2JQ, UK
| | - Carlos Marcelino Rodriguez Lopez
- Plant Research Centre, School of Agriculture, Food and Wine, Faculty of Sciences, University of Adelaide, Waite Campus, PMB1, Glen Osmond, SA, 5064, Australia
| | - Sue J Welham
- Rothamsted Research, Harpenden, Herts AL5 2JQ, UK
| | | | - Clare J Hopkins
- Rothamsted Research, Harpenden, Herts AL5 2JQ, UK
- Department of Pathology, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Michael J Wilkinson
- Plant Research Centre, School of Agriculture, Food and Wine, Faculty of Sciences, University of Adelaide, Waite Campus, PMB1, Glen Osmond, SA, 5064, Australia
| | - Graham J King
- Rothamsted Research, Harpenden, Herts AL5 2JQ, UK
- Current address: Southern Cross Plant Science, Southern Cross University, Lismore, NSW 2480, Australia
| |
Collapse
|
31
|
Abstract
This review addresses the mechanisms by which epigenetic variation modulates plant gene regulation and phenotype. In particular we explore the scope for harnessing such processes within the context of crop genetic improvement. We focus on the role of DNA methylation as an epigenetic mark that contributes to epiallelic diversity and modulation of gene regulation. We outline the prevalence and distribution of epigenetic marks in relation to eukaryote developmental processes, and in particular identify where this may be relevant to crop traits both in terms of specific developmental stages and in relation to physiological responses to environmental change. Recent whole genome surveys have identified specific characteristics of the distribution of DNA methylation within plant genomes. Together with greater understanding of the mode of action of different maintenance and de novo methyltransferases, this provides an opportunity to modulate DNA methylation status at specific loci as an intervention strategy in crop genetic improvement. We discuss alternative approaches that may be suitable for harnessing such induced epiallelic variation. Most of the discussion is associated with Brassica crops, which demonstrate considerable morphological plasticity, segmental chromosomal duplication, and polyploidy.
Collapse
|
32
|
Abstract
In eukaryotic genomes, gene expression and DNA recombination are affected by structural chromatin traits. Chromatin structure is shaped by the activity of enzymes that either introduce covalent modifications in DNA and histone proteins or use energy from ATP to disrupt histone-DNA interactions. The genomic 'marks' that are generated by covalent modifications of histones and DNA, or by the deposition of histone variants, are susceptible to being altered in response to stress. Recent evidence has suggested that proteins generating these epigenetic marks play crucial roles in the defence against pathogens. Histone deacetylases are involved in the activation of jasmonic acid- and ethylene-sensitive defence mechanisms. ATP-dependent chromatin remodellers mediate the constitutive repression of the salicylic acid-dependent pathway, whereas histone methylation at the WRKY70 gene promoter affects the activation of this pathway. Interestingly, bacterial-infected tissues show a net reduction in DNA methylation, which may affect the disease resistance genes responsible for the surveillance against pathogens. As some epigenetic marks can be erased or maintained and transmitted to offspring, epigenetic mechanisms may provide plasticity for the dynamic control of emerging pathogens without the generation of genomic lesions.
Collapse
Affiliation(s)
- María E Alvarez
- CIQUIBIC-CONICET, Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, 5000 Córdoba, Argentina.
| | | | | |
Collapse
|
33
|
Costa-Nunes P, Pontes O, Preuss SB, Pikaard CS. Extra views on RNA-dependent DNA methylation and MBD6-dependent heterochromatin formation in nucleolar dominance. NUCLEUS (AUSTIN, TEX.) 2010; 1:254-9. [PMID: 21327072 DOI: 10.4161/nucl.1.3.11741] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Accepted: 03/02/2010] [Indexed: 11/19/2022]
Abstract
Nucleolar dominance is a widespread epigenetic phenomenon, describing the preferential silencing of ribosomal RNA (rRNA) genes inherited from one progenitor of an interspecific hybrid, independent of maternal or paternal effects. In the allotetraploid hybrid plant species Arabidopsis suecica, A. thaliana-derived rRNA genes are silenced whereas the A. arenosa-derived rRNA genes are transcribed. We reported previously on an RNAi-based screen of DNA methyltransferases, methylcytosine binding proteins and RNA-dependent DNA methylation pathway proteins that identified specific activities required for the establishment or enforcement of nucleolar dominance. Here we present additional molecular and cell biological evidence that siRNA-directed cytosine methylation and the methylcytosine binding protein MBD6 bring about large-scale chromosomal effects on rRNA gene loci subjected to nucleolar dominance in A. suecica.
Collapse
|
34
|
Kandasamy MK, McKinney EC, Deal RB, Smith AP, Meagher RB. Arabidopsis actin-related protein ARP5 in multicellular development and DNA repair. Dev Biol 2009; 335:22-32. [PMID: 19679120 PMCID: PMC2778271 DOI: 10.1016/j.ydbio.2009.08.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2009] [Revised: 07/31/2009] [Accepted: 08/04/2009] [Indexed: 10/20/2022]
Abstract
Actin-related protein 5 (ARP5) is a conserved subunit of the INO80 chromatin-remodeling complex in yeast and mammals. We have characterized the expression and subcellular distribution of Arabidopsis thaliana ARP5 and explored its role in the epigenetic control of multicellular development and DNA repair. ARP5-specific monoclonal antibodies localized ARP5 protein to the nucleoplasm of interphase cells in Arabidopsis and Nicotiana tabacum. ARP5 promoter-reporter fusions and the ARP5 protein are ubiquitously expressed. A null mutant and a severe knockdown allele produced moderately dwarfed plants with all organs smaller than the wild type. The small and slightly deformed organs such as leaves and hypocotyls were composed of small-sized cells. The ratio of leaf stomata to epidermal cells was high in the mutant, which also exhibited a delayed stomatal development compared with the wild type. Mutant plants were hypersensitive to DNA-damaging reagents including hydroxyurea, methylmethane sulfonate, and bleocin, demonstrating a role for ARP5 in DNA repair. Interestingly, the hypersensitivity phenotype of ARP5 null allele arp5-1 is stronger than the severe knockdown allele arp5-2. Moreover, a wild-type transgene fully complemented all developmental and DNA repair mutant phenotypes. Despite the common participation of both ARP4 and ARP5 in the INO80 complex, ARP4- and ARP5-deficient plants displayed only a small subset of common phenotypes and each displayed novel phenotypes, suggesting that in Arabidopsis they have both shared and unique functions.
Collapse
Affiliation(s)
| | - Elizabeth C. McKinney
- Department of Genetics, Davison Life Sciences Complex, University of Georgia, Athens, GA 30602, USA
| | - Roger B. Deal
- Department of Genetics, Davison Life Sciences Complex, University of Georgia, Athens, GA 30602, USA
| | - Aaron P. Smith
- Department of Genetics, Davison Life Sciences Complex, University of Georgia, Athens, GA 30602, USA
| | - Richard B. Meagher
- Department of Genetics, Davison Life Sciences Complex, University of Georgia, Athens, GA 30602, USA
| |
Collapse
|
35
|
Pontes O, Costa-Nunes P, Vithayathil P, Pikaard CS. RNA polymerase V functions in Arabidopsis interphase heterochromatin organization independently of the 24-nt siRNA-directed DNA methylation pathway. MOLECULAR PLANT 2009; 2:700-710. [PMID: 19825650 PMCID: PMC2902898 DOI: 10.1093/mp/ssp006] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2008] [Accepted: 01/16/2009] [Indexed: 05/19/2023]
Abstract
In Arabidopsis, pericentromeric repeats, retroelements, and silenced rRNA genes are assembled into heterochromatin within nuclear structures known as chromocenters. The mechanisms governing higher-order heterochromatin organization are poorly understood but 24-nt small interfering RNAs (siRNAs) are known to play key roles in heterochromatin formation. Nuclear RNA polymerase IV (Pol IV), RNA-DEPENDENT RNA POLYMERASE 2 (RDR2), and DICER-LIKE 3 (DCL3) are required for biogenesis of 24-nt siRNAs that associate with ARGONAUTE 4 (AGO4). Nuclear RNA polymerase V (Pol V) collaborates with DRD1 (DEFICIENT IN RNA-DEPENDENT DNA METHYLATION 1) to generate transcripts at heterochromatic loci that are hypothesized to bind to siRNA-AGO4 complexes and subsequently recruit the de-novo DNA methylation and/or histone modifying machinery. Here, we report that decondensation of the major pericentromeric repeats and depletion of the heterochromatic mark histone H3 lysine 9 dimethylation at chromocenters occurs specifically in pol V and drd1 mutants. Disruption of pericentromeric repeats condensation is coincident with transcriptional reactivation of specific classes of pericentromeric 180-bp repeats. We further demonstrate that Pol V functions independently of Pol IV, RDR2, and DCL3-mediated siRNA production to affect interphase heterochromatin organization, possibly by involving RNAs that recruit structural or chromatin-modifying proteins.
Collapse
Affiliation(s)
- Olga Pontes
- Biology Department, Washington University, 1 Brookings Drive, St Louis, MO 63130, USA.
| | - Pedro Costa-Nunes
- Biology Department, Washington University, 1 Brookings Drive, St Louis, MO 63130, USA
| | - Paul Vithayathil
- Biology Department, Washington University, 1 Brookings Drive, St Louis, MO 63130, USA
| | - Craig S Pikaard
- Biology Department, Washington University, 1 Brookings Drive, St Louis, MO 63130, USA
| |
Collapse
|
36
|
Johannes F, Porcher E, Teixeira FK, Saliba-Colombani V, Simon M, Agier N, Bulski A, Albuisson J, Heredia F, Audigier P, Bouchez D, Dillmann C, Guerche P, Hospital F, Colot V. Assessing the impact of transgenerational epigenetic variation on complex traits. PLoS Genet 2009; 5:e1000530. [PMID: 19557164 PMCID: PMC2696037 DOI: 10.1371/journal.pgen.1000530] [Citation(s) in RCA: 491] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Accepted: 05/22/2009] [Indexed: 11/24/2022] Open
Abstract
Loss or gain of DNA methylation can affect gene expression and is sometimes transmitted across generations. Such epigenetic alterations are thus a possible source of heritable phenotypic variation in the absence of DNA sequence change. However, attempts to assess the prevalence of stable epigenetic variation in natural and experimental populations and to quantify its impact on complex traits have been hampered by the confounding effects of DNA sequence polymorphisms. To overcome this problem as much as possible, two parents with little DNA sequence differences, but contrasting DNA methylation profiles, were used to derive a panel of epigenetic Recombinant Inbred Lines (epiRILs) in the reference plant Arabidopsis thaliana. The epiRILs showed variation and high heritability for flowering time and plant height (∼30%), as well as stable inheritance of multiple parental DNA methylation variants (epialleles) over at least eight generations. These findings provide a first rationale to identify epiallelic variants that contribute to heritable variation in complex traits using linkage or association studies. More generally, the demonstration that numerous epialleles across the genome can be stable over many generations in the absence of selection or extensive DNA sequence variation highlights the need to integrate epigenetic information into population genetics studies. DNA methylation is defined as an epigenetic modification because it can be inherited across cell division. Since variations in DNA methylation can affect gene expression and be inherited across generations, they can provide a source of heritable phenotypic variation that is not caused by changes in the DNA sequence. However, the extent to which this type of phenotypic variation occurs in natural or experimental populations is unknown, partly because of the difficulty in teasing apart the effect of DNA methylation variants (epialleles) from that of the DNA sequence variants also present in these populations. To overcome this problem, we have derived a population of epigenetic recombinant inbred lines in the plant Arabidopsis thaliana, using parents with few DNA sequence differences but contrasting DNA methylation profiles. This population showed variation and a high degree of heritability for two complex traits, flowering time and plant height. Multiple parental DNA methylation differences were also found to be stably inherited over eight generations in this population. These findings reveal the potential impact of heritable DNA methylation variation on complex traits and demonstrate the importance of integrating epigenetic information in population genetics studies.
Collapse
Affiliation(s)
- Frank Johannes
- Unité de Recherche en Génomique Végétale, Centre National de la Recherche Scientifique (CNRS) UMR 8114, Institut National de la Recherche Agronomique (INRA) UMR 1165, Université d'Evry Val d'Essonne, Evry, France
- Institut Jean-Pierre Bourgin, Station de Génétique et d'Amélioration des Plantes UR 254, INRA, Versailles, France
- Laboratoire de Physique Théorique et Modèles Statistiques, CNRS UMR 8626, Université Paris-Sud, Orsay, France
- Groningen Bioinformatics Centre, University of Groningen, Haren, The Netherlands
| | - Emmanuelle Porcher
- Institut Jean-Pierre Bourgin, Station de Génétique et d'Amélioration des Plantes UR 254, INRA, Versailles, France
- Ferme du Moulon, Université Paris-Sud, INRA, UMR 0320/UMR 8120, Génétique Végétale, Gif-sur-Yvette, France
| | - Felipe K. Teixeira
- Unité de Recherche en Génomique Végétale, Centre National de la Recherche Scientifique (CNRS) UMR 8114, Institut National de la Recherche Agronomique (INRA) UMR 1165, Université d'Evry Val d'Essonne, Evry, France
- CNRS UMR 8186, Département de Biologie, Ecole Normale Supérieure, Paris, France
| | - Vera Saliba-Colombani
- Institut Jean-Pierre Bourgin, Station de Génétique et d'Amélioration des Plantes UR 254, INRA, Versailles, France
- Ferme du Moulon, Université Paris-Sud, INRA, UMR 0320/UMR 8120, Génétique Végétale, Gif-sur-Yvette, France
| | - Matthieu Simon
- Institut Jean-Pierre Bourgin, Station de Génétique et d'Amélioration des Plantes UR 254, INRA, Versailles, France
| | - Nicolas Agier
- Unité de Recherche en Génomique Végétale, Centre National de la Recherche Scientifique (CNRS) UMR 8114, Institut National de la Recherche Agronomique (INRA) UMR 1165, Université d'Evry Val d'Essonne, Evry, France
| | - Agnès Bulski
- Unité de Recherche en Génomique Végétale, Centre National de la Recherche Scientifique (CNRS) UMR 8114, Institut National de la Recherche Agronomique (INRA) UMR 1165, Université d'Evry Val d'Essonne, Evry, France
- CNRS UMR 8186, Département de Biologie, Ecole Normale Supérieure, Paris, France
| | - Juliette Albuisson
- Unité de Recherche en Génomique Végétale, Centre National de la Recherche Scientifique (CNRS) UMR 8114, Institut National de la Recherche Agronomique (INRA) UMR 1165, Université d'Evry Val d'Essonne, Evry, France
| | - Fabiana Heredia
- Unité de Recherche en Génomique Végétale, Centre National de la Recherche Scientifique (CNRS) UMR 8114, Institut National de la Recherche Agronomique (INRA) UMR 1165, Université d'Evry Val d'Essonne, Evry, France
| | - Pascal Audigier
- Unité de Recherche en Génomique Végétale, Centre National de la Recherche Scientifique (CNRS) UMR 8114, Institut National de la Recherche Agronomique (INRA) UMR 1165, Université d'Evry Val d'Essonne, Evry, France
| | - David Bouchez
- Institut Jean-Pierre Bourgin, Station de Génétique et d'Amélioration des Plantes UR 254, INRA, Versailles, France
| | - Christine Dillmann
- Ferme du Moulon, Université Paris-Sud, INRA, UMR 0320/UMR 8120, Génétique Végétale, Gif-sur-Yvette, France
| | - Philippe Guerche
- Institut Jean-Pierre Bourgin, Station de Génétique et d'Amélioration des Plantes UR 254, INRA, Versailles, France
| | - Frédéric Hospital
- Laboratoire de Physique Théorique et Modèles Statistiques, CNRS UMR 8626, Université Paris-Sud, Orsay, France
- INRA, UMR 1313 Génétique Animale et Biologie Intégrative, Jouy-en-Josas, France
- * E-mail: (FH); (VC)
| | - Vincent Colot
- Unité de Recherche en Génomique Végétale, Centre National de la Recherche Scientifique (CNRS) UMR 8114, Institut National de la Recherche Agronomique (INRA) UMR 1165, Université d'Evry Val d'Essonne, Evry, France
- CNRS UMR 8186, Département de Biologie, Ecole Normale Supérieure, Paris, France
- * E-mail: (FH); (VC)
| |
Collapse
|
37
|
Teixeira FK, Heredia F, Sarazin A, Roudier F, Boccara M, Ciaudo C, Cruaud C, Poulain J, Berdasco M, Fraga MF, Voinnet O, Wincker P, Esteller M, Colot V. A role for RNAi in the selective correction of DNA methylation defects. Science 2009; 323:1600-4. [PMID: 19179494 DOI: 10.1126/science.1165313] [Citation(s) in RCA: 260] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
DNA methylation is essential for silencing transposable elements and some genes in higher eukaryotes, which suggests that this modification must be tightly controlled. However, accidental changes in DNA methylation can be transmitted through mitosis (as in cancer) or meiosis, leading to epiallelic variation. We demonstrated the existence of an efficient mechanism that protects against transgenerational loss of DNA methylation in Arabidopsis. Remethylation is specific to the subset of heavily methylated repeats that are targeted by the RNA interference (RNAi) machinery. This process does not spread into flanking regions, is usually progressive over several generations, and faithfully restores wild-type methylation over target sequences in an RNAi-dependent manner. Our findings suggest an important role for RNAi in protecting genomes against long-term epigenetic defects.
Collapse
Affiliation(s)
- Felipe Karam Teixeira
- Unité de Recherche en Génomique Végétale, CNRS UMR 8114, Institut National de la Recherche Argonomique UMR 1165, Université d'Evry Val d'Essonne, 91057 Evry Cedex, France
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Fujimoto R, Sasaki T, Inoue H, Nishio T. Hypomethylation and transcriptional reactivation of retrotransposon-like sequences in ddm1 transgenic plants of Brassica rapa. PLANT MOLECULAR BIOLOGY 2008; 66:463-73. [PMID: 18236011 DOI: 10.1007/s11103-007-9285-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2007] [Accepted: 12/21/2007] [Indexed: 05/08/2023]
Abstract
DNA methylation and histone modification play important roles in regulating gene expression. The DDM1 gene in Arabidopsis thaliana (AtDDM1) is required for the maintenance of DNA methylation level and histone H3 methylation pattern. We isolated DDM1 homologs of Brassica rapa, BrDDM1a and BrDDM1b, which have 84.4% and 84.1% deduced amino acid sequence identities with AtDDM1, respectively. Both the BrDDM1a and BrDDM1b genes were found to be expressed in vegetative and reproductive tissues. B. rapa ddm1-RNAi transgenic plants with reduced levels of BrDDM1a/BrDDM1b expression showed genome-wide and non-tissue-specific demethylation. These results suggest that the BrDDM1a and BrDDM1b genes are orthologs of AtDDM1 and are required for the maintenance of DNA methylation as is AtDDM1. Despite genome-wide demethylation, developmental abnormalities were not found in the ddm1-RNAi transgenic plants. Dominance relationships of SP11/SCR alleles, the determinant of pollen recognition specificity in Brassica self-incompatibility, in S heterozygotes in B. rapa were not influenced by the low level of the BrDDM1 expression. Transcriptional reactivation of retrotransposon-like sequences observed in the ddm1-RNAi transgenic plants indicates that BrDDM1a and BrDDM1b participate in silencing of retrotransposons. Hypomethylation states of the ddm1-RNAi transgenic plants were inherited by plants of the next generation even by plants which had lost the RNAi construct by segregation. Remethylation was observed in a few progenies. Efficiencies of remethylation in the progenies without the RNAi construct were different between 18S rDNA, BoSTF12a/15a, and BrTto1 sequences.
Collapse
Affiliation(s)
- Ryo Fujimoto
- Tohoku University, Aoba-ku, Sendai, 981-8555, Japan
| | | | | | | |
Collapse
|
39
|
Rozhon W, Baubec T, Mayerhofer J, Mittelsten Scheid O, Jonak C. Rapid quantification of global DNA methylation by isocratic cation exchange high-performance liquid chromatography. Anal Biochem 2008; 375:354-60. [PMID: 18249178 DOI: 10.1016/j.ab.2008.01.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2007] [Accepted: 01/03/2008] [Indexed: 10/22/2022]
Abstract
The DNA of many eukaryotes is methylated at specific cytosine residues in connection with gene regulation. Here we report a method for the quantification of global cytosine methylation based on enzymatic hydrolysis of DNA, dephosphorylation, and subsequent high-performance cation exchange chromatography. Nucleosides are separated in less than 3 min under isocratic conditions on a benzenesulfonic acid-modified silica phase and detected by UV absorption. As little as 1 microg of DNA is sufficient to measure 5-methyldeoxycytosine levels with a typical relative standard deviation of less than 3%. As a proof of concept, the method was applied for analysis of DNA from several Arabidopsis thaliana mutants affected in DNA methylation and from Medicago sativa seedlings treated with the environmental pollutant chromium(VI).
Collapse
Affiliation(s)
- Wilfried Rozhon
- Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, 1030 Vienna, Austria.
| | | | | | | | | |
Collapse
|
40
|
Fang JG, Chao CT. Methylation-sensitive amplification polymorphism in date palms (Phoenix dactylifera L.) and their off-shoots. PLANT BIOLOGY (STUTTGART, GERMANY) 2007; 9:526-33. [PMID: 17642034 DOI: 10.1055/s-2007-964934] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
DNA methylation plays an important role in the regulation of gene expression in eukaryotes. In this study, the extent and patterns of DNA methylation were assessed in date palm mother-plants and their off-shoots using the methylation-sensitive amplified polymorphism (MSAP) technique. Three types of bands were generated using 12 pairs of primers. Type I were present in both ECOR I + HPA II and ECOR I + MSP I lanes; type II were present in ECOR I + HPA II lanes, but not in ECOR I + MSP I lanes; and type III bands were present in ECOR I + MSP I lanes, but not in ECOR I + HPA II lanes. The total numbers of these three types of bands were 782, 55, and 34, respectively. Among these three types of bands, the polymorphic bands were, respectively, 37, 10, and 0. The distribution of polymorphic bands among mother-plants and off-shoots suggests the methylation variation was present in both the mother-plants and off-shoots. Forty- four out of these 47 polymorphic bands show clear difference between mother-plant and off-shoots: 38 were present only in off-shoots and 6 in both mother-plants and off-shoots. Compared to methylation status in mother-plants, the methylation variation during off-shoot growth of date palm can be characterized as a process involving primarily de-methylation. Hypomethylation of DNA in off-shoots, compared with mother-plants, reflects the marked expression of this molecular feature, which may be related to gene expression during off-shoot development. The methylation or de-methylation status of specific loci in the mother-plants and their off-shoots were probably random events.
Collapse
Affiliation(s)
- J-G Fang
- Horticultural College, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China.
| | | |
Collapse
|
41
|
Bond DM, Finnegan EJ. Passing the message on: inheritance of epigenetic traits. TRENDS IN PLANT SCIENCE 2007; 12:211-6. [PMID: 17434332 DOI: 10.1016/j.tplants.2007.03.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2006] [Revised: 02/13/2007] [Accepted: 03/27/2007] [Indexed: 05/14/2023]
Abstract
Epigenetic modifiers play an important role in genome organization, stability and the control of gene expression. Three research groups that are exploring the transfer of epigenetic information between generations have recently published papers. Mary Alleman et al. have shown that RNA-directed chromatin changes mediate paramutation in maize, and Minoo Rassoulzadegan et al. have demonstrated that RNA also plays a role in paramutation in mice. A new aspect of epigenetic regulation has been revealed by Jean Molinier et al. - they have demonstrated that the memory of exposure to stress is transferred through several generations.
Collapse
Affiliation(s)
- Donna M Bond
- CSIRO, Plant Industry, Canberra, ACT 2601, Australia
| | | |
Collapse
|
42
|
GRANT-DOWNTON RT, DICKINSON HG. Epigenetics and its implications for plant biology. 1. The epigenetic network in plants. ANNALS OF BOTANY 2005; 96:1143-64. [PMID: 16254022 PMCID: PMC4247072 DOI: 10.1093/aob/mci273] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
BACKGROUND Epigenetics has rapidly evolved in the past decade to form an exciting new branch of biology. In modern terms, 'epigenetics' studies molecular pathways regulating how the genes are packaged in the chromosome and expressed, with effects that are heritable between cell divisions and even across generations. CONTEXT Epigenetic mechanisms often conflict with Mendelian models of genetics, and many components of the epigenetic systems in plants appeared anomalous. However, it is now clear that these systems govern how the entire genome operates and evolves. SCOPE In the first part of a two-part review, how epigenetic systems in plants were elucidated is addressed. Also there is a discussion on how the different components of the epigenetic system--regulating DNA methylation, histones and their post-translational modification, and pathways recognizing aberrant transcripts--may work together.
Collapse
|
43
|
Ruiz-García L, Cervera MT, Martínez-Zapater JM. DNA methylation increases throughout Arabidopsis development. PLANTA 2005; 222:301-6. [PMID: 15968513 DOI: 10.1007/s00425-005-1524-6] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2004] [Accepted: 02/16/2005] [Indexed: 05/03/2023]
Abstract
We used amplified fragment length polymorphisms (AFLP) to analyze the stability of DNA methylation throughout Arabidopsis development. AFLP can detect genome-wide changes in cytosine methylation produced by DNA demethylation agents, such as 5-azacytidine, or specific mutations at the DDM1 locus. In both cases, cytosine demethylation is associated with a general increase in the presence of amplified fragments. Using this approach, we followed DNA methylation at methylation sensitive restriction sites throughout Arabidopsis development. The results show a progressive DNA methylation trend from cotyledons to vegetative organs to reproductive organs.
Collapse
Affiliation(s)
- L Ruiz-García
- Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología, CSIC, Campus de la Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | | | | |
Collapse
|
44
|
Zemach A, Li Y, Wayburn B, Ben-Meir H, Kiss V, Avivi Y, Kalchenko V, Jacobsen SE, Grafi G. DDM1 binds Arabidopsis methyl-CpG binding domain proteins and affects their subnuclear localization. THE PLANT CELL 2005; 17:1549-58. [PMID: 15805479 PMCID: PMC1091773 DOI: 10.1105/tpc.105.031567] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2005] [Accepted: 03/14/2005] [Indexed: 05/21/2023]
Abstract
Methyl-CpG binding domain (MBD) proteins in Arabidopsis thaliana bind in vitro methylated CpG sites. Here, we aimed to characterize the binding properties of AtMBDs to chromatin in Arabidopsis nuclei. By expressing in wild-type cells AtMBDs fused to green fluorescent protein (GFP), we showed that AtMBD7 was evenly distributed at all chromocenters, whereas AtMBD5 and 6 showed preference for two perinucleolar chromocenters adjacent to nucleolar organizing regions. AtMBD2, previously shown to be incapable of binding in vitro-methylated CpG, was dispersed within the nucleus, excluding chromocenters and the nucleolus. Recruitment of AtMBD5, 6, and 7 to chromocenters was disrupted in ddm1 and met1 mutant cells, where a significant reduction in cytosine methylation occurs. In these mutant cells, however, AtMBD2 accumulated at chromocenters. No effect on localization was observed in the chromomethylase3 mutant showing reduced CpNpG methylation or in kyp-2 displaying a reduction in Lys 9 histone H3 methylation. Transient expression of DDM1 fused to GFP showed that DDM1 shares common sites with AtMBD proteins. Glutathione S-transferase pull-down assays demonstrated that AtMBDs bind DDM1; the MBD motif was sufficient for this interaction. Our results suggest that the subnuclear localization of AtMBD is not solely dependent on CpG methylation; DDM1 may facilitate localization of AtMBDs at specific nuclear domains.
Collapse
Affiliation(s)
- Assaf Zemach
- Department of Plant Sciences, Weizman Institute of Science, Rehovot 76100, Israel
| | | | | | | | | | | | | | | | | |
Collapse
|
45
|
DiPaolo C, Kieft R, Cross M, Sabatini R. Regulation of trypanosome DNA glycosylation by a SWI2/SNF2-like protein. Mol Cell 2005; 17:441-51. [PMID: 15694344 DOI: 10.1016/j.molcel.2004.12.022] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2004] [Revised: 11/16/2004] [Accepted: 12/10/2004] [Indexed: 11/16/2022]
Abstract
Synthesis of the modified thymine base beta-D-glucosyl-hydroxymethyluracil, or J, within telomeric DNA of Trypanosoma brucei correlates with the bloodstream-form-specific epigenetic silencing of telomeric variant surface glycoprotein genes involved in antigenic variation. The mechanism of developmental and telomeric-specific regulation of J synthesis is unknown. We have previously identified a J binding protein (JBP1) involved in propagating J synthesis. We have now identified a homolog of JBP1, JBP2, containing a domain related to the SWI2/SNF2 family of chromatin remodeling proteins that is upregulated in bloodstream form cells and interacts with nuclear chromatin. We show that expression of JBP2 in procyclic form cells leads to de novo J synthesis within telomeric regions of the chromosome and that this activity is inhibited after mutagenesis of conserved residues critical for SWI2/SNF2 function. We propose a model in which chromatin remodeling by JBP2 regulates the initial sites of J synthesis within bloodstream form trypanosome DNA, with further propagation and maintenance of J by JBP1.
Collapse
Affiliation(s)
- Courtney DiPaolo
- Global Infectious Diseases Program, Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | | | | | | |
Collapse
|
46
|
Abstract
The plant life cycle involves a series of developmental phase transitions. These transitions require the regulation and highly co-ordinated expression of many genes. Epigenetic controls have now been shown to be a key element of this mechanism of regulation. In the model plant Arabidopsis, recent genetic and molecular studies on chromatin have begun to dissect the molecular basis of these epigenetic controls. Chromatin dynamics represent the emerging and exciting field of gene regulation notably involved in plant developmental transitions. By comparing plant and animal systems, new insights into the molecular complexes and mechanisms governing development can be delineated. We are now beginning to identify the components of chromatin complexes and their functions.
Collapse
Affiliation(s)
- Frédéric Berger
- Laboratoire RDP, UMR 5667, ENS-Lyon, 46 allée d'Italie, F-69364 Lyon cedex 07, France
| | | |
Collapse
|
47
|
Jaligot E, Beulé T, Baurens FC, Billotte N, Rival A. Search for methylation-sensitive amplification polymorphisms associated with the mantled variant phenotype in oil palm (Elaeis guineensis Jacq). Genome 2004; 47:224-8. [PMID: 15060619 DOI: 10.1139/g03-085] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The methylation-sensitive amplification polymorphism (MSAP) technique has been employed on somatic embryo-derived oil palms (Elaeis guineensis Jacq.) to identify methylation polymorphisms correlated with the "mantled" somaclonal variation. The variant phenotype displays an unstable feminization of male organs in both male and female flowers. Using MSAP, the methylation status of CCGG sites was compared in three normal versus three mantled regenerants sampled in clonal populations obtained through somatic embryogenesis from four genotypically distinct mother palms. Overall, 64 selective primer combinations were used and they have amplified 23 markers exhibiting a differential methylation pattern between the two phenotypes. Our results indicate that CCGG sites are poorly affected by the considerable decrease in global DNA methylation that has been previously associated with the mantled phenotype. Each of the 23 markers isolated in the present study could discriminate between the two phenotypes only when they were from the same genetic origin. This result hampers at the moment the direct use of MSAP markers for the early detection of variants, even though valuable information on putative target sequences will be obtained from a further characterization of these polymorphic markers.
Collapse
Affiliation(s)
- E Jaligot
- UMR 1098 Biologie du Dévelopment des Espèces Pèrennes Cultivées, CIRAD-CP/IRD, Centre IRD, Montpellier, France.
| | | | | | | | | |
Collapse
|
48
|
Yan Q, Cho E, Lockett S, Muegge K. Association of Lsh, a regulator of DNA methylation, with pericentromeric heterochromatin is dependent on intact heterochromatin. Mol Cell Biol 2003; 23:8416-28. [PMID: 14612388 PMCID: PMC262679 DOI: 10.1128/mcb.23.23.8416-8428.2003] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2003] [Revised: 06/30/2003] [Accepted: 08/15/2003] [Indexed: 11/20/2022] Open
Abstract
The eukaryotic genome is packaged into distinct domains of transcriptionally active euchromatin and silent heterochromatin. A hallmark of mammalian heterochromatin is CpG methylation. Lsh, a member of the SNF2 family, is a major regulator of DNA methylation in mice and thus crucial for normal heterochromatin formation. In order to define the molecular function of Lsh, we examined its cellular localization and its association with chromatin. Our studies demonstrate that Lsh is an exclusively nuclear protein, and we define a nuclear localization domain within the N-terminal portion of Lsh. Lsh strongly associates with chromatin and requires the internal and C-terminal regions for this interaction. Lsh accumulates at pericentromeric heterochromatin, suggesting a direct role for Lsh in the methylation of centromeric DNA sequences and the formation of heterochromatin. In search of a signal that is responsible for Lsh recruitment to pericentromeric heterochromatin, we found that histone tail modifications were critical. Prolonged treatment with histone deacetylase inhibitors has been reported to disrupt higher-order heterochromatin organization, and this was accompanied by dissociation of Lsh from pericentromeric heterochromatin. These results are consistent with a model in which Lsh is recruited by intact heterochromatin structure and then assists in maintaining heterochromatin organization by establishing CpG methylation patterns.
Collapse
Affiliation(s)
- Qingsheng Yan
- Laboratory of Molecular Immunoregulation, Basic Research Program, SAIC-Frederick, National Cancer Institute, Frederick, Maryland 21702, USA
| | | | | | | |
Collapse
|
49
|
Abstract
Chromatin remodeling in plants has usually been discussed in relation to aspects of genome defense such as transgene silencing and the resetting of transposon activity. The role of remodeling in controlling development has been less emphasized, although well established in animal systems. This is because cell fate in plants is often held to be entirely specified on the basis of position, apparently excluding any significant role for cell ancestry and chromatin remodeling. We argue that chromatin remodeling is used to confer mitotically heritable cell fates at late stages in pattern formation. Several examples in which chromatin remodeling factors are used to confer a memory of transient events in plant development are discussed. Because the precise biochemical functions of most remodeling factors are obscure, and little is known of plant chromatin structure, the underlying mechanisms remain poorly understood.
Collapse
Affiliation(s)
- Justin Goodrich
- Institute of Cell and Molecular Biology, University of Edinburgh, King's Buildings, Mayfield Road, United Kingdom.
| | | |
Collapse
|
50
|
Kato M, Miura A, Bender J, Jacobsen SE, Kakutani T. Role of CG and non-CG methylation in immobilization of transposons in Arabidopsis. Curr Biol 2003; 13:421-6. [PMID: 12620192 DOI: 10.1016/s0960-9822(03)00106-4] [Citation(s) in RCA: 262] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Methylation of cytosine residues in eukaryotic genomes is often associated with repeated sequences including transposons and their derivatives. Methylation has been implicated in control of two potential deleterious effects of these repeats: (1) uncontrolled transcription, which often disturbs proper expression of nearby host genes, and (2) changes in genome structure by transposition and ectopic recombination. Arabidopsis thaliana provides a genetically tractable system to examine these possibilities, since viable mutants in DNA methyltransferases are available. Arabidopsis MET1 (METHYLTRANSFERASE1, ortholog of mammalian DNA methyltransferase Dnmt1) is necessary for maintaining genomic cytosine methylation at 5'-CG-3' sites. Arabidopsis additionally methylates non-CG sites using CHROMOMETHYLASE3 (CMT3). We examined the mobility of endogenous CACTA transposons in met1, cmt3, and cmt3-met1 mutants. High-frequency transposition of CACTA elements was detected in cmt3-met1 double mutants. Single mutants in either met1 or cmt3 were much less effective in mobilization, despite significant induction of CACTA transcript accumulation. These results lead us to conclude that CG and non-CG methylation systems redundantly function for immobilization of transposons. Non-CG methylation in plants may have evolved as an additional epigenetic tag dedicated to transposon control. This view is consistent with the recent finding that CMT3 preferentially methylates transposon-related sequences.
Collapse
Affiliation(s)
- Masaomi Kato
- Department of Integrated Genetics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | | | | | | | | |
Collapse
|