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Barro-Trastoy D, Köhler C. Helitrons: genomic parasites that generate developmental novelties. Trends Genet 2024; 40:437-448. [PMID: 38429198 DOI: 10.1016/j.tig.2024.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 02/03/2024] [Accepted: 02/05/2024] [Indexed: 03/03/2024]
Abstract
Helitrons, classified as DNA transposons, employ rolling-circle intermediates for transposition. Distinguishing themselves from other DNA transposons, they leave the original template element unaltered during transposition, which has led to their characterization as 'peel-and-paste elements'. Helitrons possess the ability to capture and mobilize host genome fragments, with enormous consequences for host genomes. This review discusses the current understanding of Helitrons, exploring their origins, transposition mechanism, and the extensive repercussions of their activity on genome structure and function. We also explore the evolutionary conflicts stemming from Helitron-transposed gene fragments and elucidate their domestication for regulating responses to environmental challenges. Looking ahead, further research in this evolving field promises to bring interesting discoveries on the role of Helitrons in shaping genomic landscapes.
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Affiliation(s)
- Daniela Barro-Trastoy
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Claudia Köhler
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany; Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden.
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2
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Li J, Zhang Q, Wang Z, Liu Q. The roles of epigenetic regulators in plant regeneration: Exploring patterns amidst complex conditions. PLANT PHYSIOLOGY 2024; 194:2022-2038. [PMID: 38290051 PMCID: PMC10980418 DOI: 10.1093/plphys/kiae042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/06/2023] [Accepted: 12/17/2023] [Indexed: 02/01/2024]
Abstract
Plants possess remarkable capability to regenerate upon tissue damage or optimal environmental stimuli. This ability not only serves as a crucial strategy for immobile plants to survive through harsh environments, but also made numerous modern plant improvements techniques possible. At the cellular level, this biological process involves dynamic changes in gene expression that redirect cell fate transitions. It is increasingly recognized that chromatin epigenetic modifications, both activating and repressive, intricately interact to regulate this process. Moreover, the outcomes of epigenetic regulation on regeneration are influenced by factors such as the differences in regenerative plant species and donor tissue types, as well as the concentration and timing of hormone treatments. In this review, we focus on several well-characterized epigenetic modifications and their regulatory roles in the expression of widely studied morphogenic regulators, aiming to enhance our understanding of the mechanisms by which epigenetic modifications govern plant regeneration.
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Affiliation(s)
- Jiawen Li
- State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Qiyan Zhang
- State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Zejia Wang
- State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Qikun Liu
- State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
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3
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Roelfs KU, Känel A, Twyman RM, Prüfer D, Schulze Gronover C. Epigenetic variation in early and late flowering plants of the rubber-producing Russian dandelion Taraxacum koksaghyz provides insights into the regulation of flowering time. Sci Rep 2024; 14:4283. [PMID: 38383610 PMCID: PMC10881582 DOI: 10.1038/s41598-024-54862-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 02/17/2024] [Indexed: 02/23/2024] Open
Abstract
The Russian dandelion (Taraxacum koksaghyz) grows in temperate zones and produces large amounts of poly(cis-1,4-isoprene) in its roots, making it an attractive alternative source of natural rubber. Most T. koksaghyz plants require vernalization to trigger flower development, whereas early flowering varieties that have lost their vernalization dependence are more suitable for breeding and domestication. To provide insight into the regulation of flowering time in T. koksaghyz, we induced epigenetic variation by in vitro cultivation and applied epigenomic and transcriptomic analysis to the resulting early flowering plants and late flowering controls, allowing us to identify differences in methylation patterns and gene expression that correlated with flowering. This led to the identification of candidate genes homologous to vernalization and photoperiodism response genes in other plants, as well as epigenetic modifications that may contribute to the control of flower development. Some of the candidate genes were homologous to known floral regulators, including those that directly or indirectly regulate the major flowering control gene FT. Our atlas of genes can be used as a starting point to investigate mechanisms that control flowering time in T. koksaghyz in greater detail and to develop new breeding varieties that are more suited to domestication.
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Affiliation(s)
- Kai-Uwe Roelfs
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, 48149, Münster, Germany
| | - Andrea Känel
- Institute of Plant Biology and Biotechnology, University of Münster, 48143, Münster, Germany
| | | | - Dirk Prüfer
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, 48149, Münster, Germany
- Institute of Plant Biology and Biotechnology, University of Münster, 48143, Münster, Germany
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4
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Ménard D, Serk H, Decou R, Pesquet E. Inducible Pluripotent Suspension Cell Cultures (iPSCs) to Study Plant Cell Differentiation. Methods Mol Biol 2024; 2722:171-200. [PMID: 37897608 DOI: 10.1007/978-1-0716-3477-6_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/30/2023]
Abstract
Inducing the differentiation of specific cell type(s) synchronously and on-demand is a great experimental system to understand the sequential progression of the cellular processes, their timing and their resulting properties for distinct isolated plant cells independently of their tissue context. The inducible differentiation in cell suspension cultures, moreover, enables to obtain large quantities of distinct cell types at specific development stage, which is not possible when using whole plants. The differentiation of tracheary elements (TEs) - the cell type responsible for the hydro-mineral sap conduction and skeletal support of plants in xylem tissues - has been the most studied using inducible cell suspension cultures. We herein describe how to establish and use inducible pluripotent suspension cell cultures (iPSCs) in Arabidopsis thaliana to trigger on-demand different cell types, such as TEs or mesophyll cells. We, moreover, describe the methods to establish, monitor, and modify the sequence, duration, and properties of differentiated cells using iPSCs.
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Affiliation(s)
- Delphine Ménard
- Department of Ecology, Environment and Plant Sciences (DEEP), Stockholm University, Stockholm, Sweden
- Umeå Plant Science Centre (UPSC), Department of Plant Physiology, Umeå University, Umeå, Sweden
| | - Henrik Serk
- Umeå Plant Science Centre (UPSC), Department of Plant Physiology, Umeå University, Umeå, Sweden
| | - Raphael Decou
- Umeå Plant Science Centre (UPSC), Department of Plant Physiology, Umeå University, Umeå, Sweden
| | - Edouard Pesquet
- Department of Ecology, Environment and Plant Sciences (DEEP), Stockholm University, Stockholm, Sweden.
- Umeå Plant Science Centre (UPSC), Department of Plant Physiology, Umeå University, Umeå, Sweden.
- Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.
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5
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Kumar M, Rani K. Epigenomics in stress tolerance of plants under the climate change. Mol Biol Rep 2023:10.1007/s11033-023-08539-6. [PMID: 37294468 DOI: 10.1007/s11033-023-08539-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 05/19/2023] [Indexed: 06/10/2023]
Abstract
BACKGROUND Climate change has had a tremendous impact on the environment in general as well as agricultural crops grown in these situations as time passed. Agricultural production of crops is less suited and of lower quality due to disturbances in plant metabolism brought on by sensitivity to environmental stresses, which are brought on by climate change. Abiotic stressors that are specific to climate change, including as drought, extremes in temperature, increasing CO2, waterlogging from heavy rain, metal toxicity, and pH changes, are known to negatively affect an array of species. Plants adapt to these challenges by undergoing genome-wide epigenetic changes, which are frequently accompanied by differences in transcriptional gene expression. The sum of a cell's biochemical modifications to its nuclear DNA, post-translational modifications to histones, and variations in the synthesis of non-coding RNAs is called an epigenome. These modifications frequently lead to variations in gene expression that occur without any alteration in the underlying base sequence. EPIGENETIC MECHANISMS AND MARKS The methylation of homologous loci by three different modifications-genomic (DNA methylation), chromatin (histone modifications), and RNA-directed DNA methylation (RdDM)-could be regarded as epigenetic mechanisms that control the regulation of differential gene expression. Stresses from the environment cause chromatin remodelling, which enables plant cells to adjust their expression patterns temporarily or permanently. EPIGENOMICS' CONSEQUENCES FOR GENOME STABILITY AND GENE EXPRESSION: DNA methylation affects gene expression in response to abiotic stressors by blocking or suppressing transcription. Environmental stimuli cause changes in DNA methylation levels, either upward in the case of hypermethylation or downward in the case of hypomethylation. The type of stress response that occurs as a result also affects the degree of DNA methylation alterations. Stress is also influenced by DRM2 and CMT3 methylating CNN, CNG, and CG. Both plant development and stress reactions depend on histone changes. Gene up-regulation is associated with histone tail phosphorylation, ubiquitination, and acetylation, while gene down-regulation is associated with de-acetylation and biotinylation. Plants undergo a variety of dynamic changes to histone tails in response to abiotic stressors. The relevance of these transcripts against stress is highlighted by the accumulation of numerous additional antisense transcripts, a source of siRNAs, caused by abiotic stresses. The study highlights the finding that plants can be protected from a range of abiotic stresses by epigenetic mechanisms such DNA methylation, histone modification, and RNA-directed DNA methylation. TRANSGENERATIONAL INHERITANCE AND SOURCES OF EPIGENETIC VARIATION: Stress results in the formation of epialleles, which are either transient or enduring epigenetic stress memory in plants. After the stress is gone, the stable memory is kept for the duration of the plant's remaining developmental cycles or passed on to the next generations, leading to plant evolution and adaptability. The bulk of epigenetic changes brought on by stress are temporary and return to normal after the stress has passed. Some of the modifications, however, might be long-lasting and transmitted across mitotic or even meiotic cell divisions. Epialleles often have genetic or non-genetic causes. Epialleles can arise spontaneously due to improper methylation state maintenance, short RNA off-target effects, or other non-genetic causes. Developmental or environmental variables that influence the stability of epigenetic states or direct chromatin modifications may also be non-genetic drivers of epigenetic variation. Transposon insertions that change local chromatin and structural rearrangements, such copy number changes that are genetically related or unrelated, are two genetic sources of epialleles. EPIGENOMICS IN CROP IMPROVEMENT To include epigenetics into crop breeding, it is necessary to create epigenetic variation as well as to identify and evaluate epialleles. Epigenome editing or epi-genomic selection may be required for epiallele creation and identification. In order to combat the challenges given by changing environments, these epigenetic mechanisms have generated novel epialleles that can be exploited to develop new crop types that are more climate-resilient. Numerous techniques can be used to alter the epigenome generally or at specific target loci in order to induce the epigenetic alterations necessary for crop development. Technologies like CRISPR/Cas9 and dCas, which have recently advanced, have opened up new avenues for the study of epigenetics. Epialleles could be employed in epigenomics-assisted breeding in addition to sequence-based markers for crop breeding. CONCLUSIONS AND FUTURE PROSPECTUS A few of the exciting questions that still need to be resolved in the area of heritable epigenetic variation include a better understanding of the epigenetic foundation of characteristics, the stability and heritability of epialleles, and the sources of epigenetic variation in crops. Investigating long intergenic non-coding RNAs (lincRNAs) as an epigenetic process might open up a new path to understanding crop plant's ability to withstand abiotic stress. For many of these technologies and approaches to be more applicable and deployable at a lower cost, technological breakthroughs will also be necessary. Breeders will probably need to pay closer attention to crop epialleles and how they can affect future responses to climate changes. The development of epialleles suitable for particular environmental circumstances may be made possible by creating targeted epigenetic changes in pertinent genes and by comprehending the molecular underpinnings of trans generational epigenetic inheritance. More research on a wider variety of plant species is required in order to fully comprehend the mechanisms that produce and stabilise epigenetic variation in crops. In addition to a collaborative and multidisciplinary effort by researchers in many fields of plant science, this will require a greater integration of the epigenomic data gathered in many crops. Before it may be applied generally, more study is required.
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Affiliation(s)
- Mithlesh Kumar
- AICRN On Potential Crops, ARS Mandor, Agriculture University, Jodhpur, 342 304, Rajasthan, India.
| | - Kirti Rani
- ICAR-National Bureau of Plant Genetic Resources (NBPGR), Regional Station, Jodhpur, 342 003, Rajasthan, India
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6
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Somaclonal Variation-Advantage or Disadvantage in Micropropagation of the Medicinal Plants. Int J Mol Sci 2023; 24:ijms24010838. [PMID: 36614275 PMCID: PMC9821087 DOI: 10.3390/ijms24010838] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/08/2022] [Accepted: 12/29/2022] [Indexed: 01/05/2023] Open
Abstract
Cell and tissue plant cultures are used either to save vulnerable species from extinction or to multiply valuable genotypes, or both, and are widely applied for economically important plant species. For medicinal plants, the use of in vitro technologies for the production of secondary metabolites and pathogen-free plants has been greatly developed. Two opposite aspects characterize the in vitro micropropagation of medicinal plants: maintaining genetic fidelity for the perpetuation and preservation of elites, and the identification and exploitation of somaclonal variations associated with new, useful traits. A balance between what is advantageous and what is undesirable is necessary, and this implies the identification of somaclonal variability at all levels, from the phenotypic to molecular ones. This review addresses the somaclonal variation arising from the in vitro multiplication of medicinal plants from three perspectives: cytogenetics, genetics, and epigenetics. The possible causes of the appearance of somaclones, the methods for their identification, and the extent to which they are desirable are presented comparatively for different plant species with therapeutic properties. The emphasis is on the subtle changes at the genetic and epigenetic level, as it results from the application of methods based on DNA markers.
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Wilkinson SW, Hannan Parker A, Muench A, Wilson RS, Hooshmand K, Henderson MA, Moffat EK, Rocha PSCF, Hipperson H, Stassen JHM, López Sánchez A, Fomsgaard IS, Krokene P, Mageroy MH, Ton J. Long-lasting memory of jasmonic acid-dependent immunity requires DNA demethylation and ARGONAUTE1. NATURE PLANTS 2023; 9:81-95. [PMID: 36604579 DOI: 10.1038/s41477-022-01313-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 11/10/2022] [Indexed: 06/17/2023]
Abstract
Stress can have long-lasting impacts on plants. Here we report the long-term effects of the stress hormone jasmonic acid (JA) on the defence phenotype, transcriptome and DNA methylome of Arabidopsis. Three weeks after transient JA signalling, 5-week-old plants retained induced resistance (IR) against herbivory but showed increased susceptibility to pathogens. Transcriptome analysis revealed long-term priming and/or upregulation of JA-dependent defence genes but repression of ethylene- and salicylic acid-dependent genes. Long-term JA-IR was associated with shifts in glucosinolate composition and required MYC2/3/4 transcription factors, RNA-directed DNA methylation, the DNA demethylase ROS1 and the small RNA (sRNA)-binding protein AGO1. Although methylome analysis did not reveal consistent changes in DNA methylation near MYC2/3/4-controlled genes, JA-treated plants were specifically enriched with hypomethylated ATREP2 transposable elements (TEs). Epigenomic characterization of mutants and transgenic lines revealed that ATREP2 TEs are regulated by RdDM and ROS1 and produce 21 nt sRNAs that bind to nuclear AGO1. Since ATREP2 TEs are enriched with sequences from IR-related defence genes, our results suggest that AGO1-associated sRNAs from hypomethylated ATREP2 TEs trans-regulate long-lasting memory of JA-dependent immunity.
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Affiliation(s)
- S W Wilkinson
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable Food, The University of Sheffield, Sheffield, UK.
| | - A Hannan Parker
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable Food, The University of Sheffield, Sheffield, UK
| | - A Muench
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable Food, The University of Sheffield, Sheffield, UK
| | - R S Wilson
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable Food, The University of Sheffield, Sheffield, UK
| | - K Hooshmand
- Department of Agroecology, Aarhus University, Slagelse, Denmark
| | - M A Henderson
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable Food, The University of Sheffield, Sheffield, UK
| | - E K Moffat
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable Food, The University of Sheffield, Sheffield, UK
| | - P S C F Rocha
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable Food, The University of Sheffield, Sheffield, UK
| | - H Hipperson
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable Food, The University of Sheffield, Sheffield, UK
| | - J H M Stassen
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable Food, The University of Sheffield, Sheffield, UK
| | - A López Sánchez
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable Food, The University of Sheffield, Sheffield, UK
| | - I S Fomsgaard
- Department of Agroecology, Aarhus University, Slagelse, Denmark
| | - P Krokene
- Division for Biotechnology and Plant Health, Norwegian Institute of Bioeconomy Research (NIBIO), Ås, Norway
| | - M H Mageroy
- Division for Biotechnology and Plant Health, Norwegian Institute of Bioeconomy Research (NIBIO), Ås, Norway
| | - J Ton
- Plants, Photosynthesis and Soil, School of Biosciences, Institute for Sustainable Food, The University of Sheffield, Sheffield, UK.
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8
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Rozov SM, Zagorskaya AA, Konstantinov YM, Deineko EV. Three Parts of the Plant Genome: On the Way to Success in the Production of Recombinant Proteins. PLANTS (BASEL, SWITZERLAND) 2022; 12:38. [PMID: 36616166 PMCID: PMC9824153 DOI: 10.3390/plants12010038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/15/2022] [Accepted: 12/16/2022] [Indexed: 06/17/2023]
Abstract
Recombinant proteins are the most important product of current industrial biotechnology. They are indispensable in medicine (for diagnostics and treatment), food and chemical industries, and research. Plant cells combine advantages of the eukaryotic protein production system with simplicity and efficacy of the bacterial one. The use of plants for the production of recombinant proteins is an economically important and promising area that has emerged as an alternative to traditional approaches. This review discusses advantages of plant systems for the expression of recombinant proteins using nuclear, plastid, and mitochondrial genomes. Possibilities, problems, and prospects of modifications of the three parts of the genome in light of obtaining producer plants are examined. Examples of successful use of the nuclear expression platform for production of various biopharmaceuticals, veterinary drugs, and technologically important proteins are described, as are examples of a high yield of recombinant proteins upon modification of the chloroplast genome. Potential utility of plant mitochondria as an expression system for the production of recombinant proteins and its advantages over the nucleus and chloroplasts are substantiated. Although these opportunities have not yet been exploited, potential utility of plant mitochondria as an expression system for the production of recombinant proteins and its advantages over the nucleus and chloroplasts are substantiated.
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Affiliation(s)
- Sergey M. Rozov
- Federal Research Center, Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, pr. Akad. Lavrentieva 10, Novosibirsk 630090, Russia
| | - Alla A. Zagorskaya
- Federal Research Center, Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, pr. Akad. Lavrentieva 10, Novosibirsk 630090, Russia
| | - Yuri M. Konstantinov
- Siberian Institute of Plant Physiology and Biochemistry, Siberian Branch of Russian Academy of Sciences, Lermontova Str. 132, Irkutsk 664033, Russia
| | - Elena V. Deineko
- Federal Research Center, Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, pr. Akad. Lavrentieva 10, Novosibirsk 630090, Russia
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9
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Aflaki F, Gutzat R, Mozgová I. Chromatin during plant regeneration: Opening towards root identity? CURRENT OPINION IN PLANT BIOLOGY 2022; 69:102265. [PMID: 35988353 DOI: 10.1016/j.pbi.2022.102265] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 06/01/2022] [Accepted: 06/28/2022] [Indexed: 06/15/2023]
Abstract
Plants show exceptional developmental plasticity and the ability to reprogram cell identities during regeneration. Although regeneration has been used in plant propagation for decades, we only recently gained detailed cellular and molecular insights into this process. Evidently, not all cell types have the same regeneration potential, and only a subset of regeneration-competent cells reach pluripotency. Pluripotent cells exhibit transcriptional similarity to root stem cells. In different plant regeneration systems, transcriptional reprogramming involves transient release of chromatin repression during pluripotency establishment and its restoration during organ or embryo differentiation. Incomplete resetting of the epigenome leads to somaclonal variation in regenerated plants. As single-cell technologies advance, we expect novel, exciting insights into epigenome dynamics during the establishment of pluripotency.
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Affiliation(s)
- Fatemeh Aflaki
- Biology Centre, Czech Academy of Sciences, Institute of Plant Molecular Biology, České Budějovice, Czech Republic
| | - Ruben Gutzat
- Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Vienna Biocenter (VBC), Vienna, 1030, Austria
| | - Iva Mozgová
- Biology Centre, Czech Academy of Sciences, Institute of Plant Molecular Biology, České Budějovice, Czech Republic; University of South Bohemia, Faculty of Science, České Budějovice, Czech Republic.
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10
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Tonosaki K, Fujimoto R, Dennis ES, Raboy V, Osabe K. Will epigenetics be a key player in crop breeding? FRONTIERS IN PLANT SCIENCE 2022; 13:958350. [PMID: 36247549 PMCID: PMC9562705 DOI: 10.3389/fpls.2022.958350] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 09/12/2022] [Indexed: 06/16/2023]
Abstract
If food and feed production are to keep up with world demand in the face of climate change, continued progress in understanding and utilizing both genetic and epigenetic sources of crop variation is necessary. Progress in plant breeding has traditionally been thought to be due to selection for spontaneous DNA sequence mutations that impart desirable phenotypes. These spontaneous mutations can expand phenotypic diversity, from which breeders can select agronomically useful traits. However, it has become clear that phenotypic diversity can be generated even when the genome sequence is unaltered. Epigenetic gene regulation is a mechanism by which genome expression is regulated without altering the DNA sequence. With the development of high throughput DNA sequencers, it has become possible to analyze the epigenetic state of the whole genome, which is termed the epigenome. These techniques enable us to identify spontaneous epigenetic mutations (epimutations) with high throughput and identify the epimutations that lead to increased phenotypic diversity. These epimutations can create new phenotypes and the causative epimutations can be inherited over generations. There is evidence of selected agronomic traits being conditioned by heritable epimutations, and breeders may have historically selected for epiallele-conditioned agronomic traits. These results imply that not only DNA sequence diversity, but the diversity of epigenetic states can contribute to increased phenotypic diversity. However, since the modes of induction and transmission of epialleles and their stability differ from that of genetic alleles, the importance of inheritance as classically defined also differs. For example, there may be a difference between the types of epigenetic inheritance important to crop breeding and crop production. The former may depend more on longer-term inheritance whereas the latter may simply take advantage of shorter-term phenomena. With the advances in our understanding of epigenetics, epigenetics may bring new perspectives for crop improvement, such as the use of epigenetic variation or epigenome editing in breeding. In this review, we will introduce the role of epigenetic variation in plant breeding, largely focusing on DNA methylation, and conclude by asking to what extent new knowledge of epigenetics in crop breeding has led to documented cases of its successful use.
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Affiliation(s)
- Kaoru Tonosaki
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
| | - Ryo Fujimoto
- Graduate School of Agricultural Science, Kobe University, Kobe, Japan
| | - Elizabeth S. Dennis
- Commonwealth Scientific and Industrial Research Organisation (CSIRO) Agriculture and Food, Canberra, ACT, Australia
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - Victor Raboy
- Independent Researcher Portland, Portland, OR, United States
| | - Kenji Osabe
- Institute of Scientific and Industrial Research (SANKEN), Osaka University, Osaka, Japan
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11
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Fukai E, Yoshikawa M, Shah N, Sandal N, Miyao A, Ono S, Hirakawa H, Akyol TY, Umehara Y, Nonomura KI, Stougaard J, Hirochika H, Hayashi M, Sato S, Andersen SU, Okazaki K. Widespread and transgenerational retrotransposon activation in inter- and intraspecies recombinant inbred populations of Lotus japonicus. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 111:1397-1410. [PMID: 35792830 DOI: 10.1111/tpj.15896] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 06/30/2022] [Indexed: 06/15/2023]
Abstract
Transposable elements (TEs) constitute a large proportion of genomes of multicellular eukaryotes, including flowering plants. TEs are normally maintained in a silenced state and their transpositions rarely occur. Hybridization between distant species has been regarded as a 'shock' that stimulates genome reorganization, including TE mobilization. However, whether crosses between genetically close parents that result in viable and fertile offspring can induce TE transpositions has remained unclear. Here, we investigated the activation of long terminal repeat (LTR) retrotransposons in three Lotus japonicus recombinant inbred line (RIL) populations. We found that at least six LTR retrotransposon families were activated and transposed in 78% of the RILs investigated. LORE1a, one of the transposed LTR retrotransposons, showed transgenerational epigenetic activation, indicating the long-term effects of epigenetic instability induced by hybridization. Our study highlights TE activation as an unexpectedly common event in plant reproduction.
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Affiliation(s)
- Eigo Fukai
- Graduate School of Science and Technology, Niigata University, Ikarashi-ninocho, 950-2181, Niigata, Japan
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2, Oowashi, Tsukuba, Ibaraki, 305-8634, Japan
- Department of Molecular Biology and Genetics, Aarhus University, 8000, Aarhus, Denmark
- Plant Cytogenetics, Department of Gene Function and Phenomics, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540, Japan
- Department of Technology Development, Kazusa DNA Research Institute, Kisarazu, Chiba, 292-0818, Japan
| | - Manabu Yoshikawa
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2, Oowashi, Tsukuba, Ibaraki, 305-8634, Japan
| | - Niraj Shah
- Department of Molecular Biology and Genetics, Aarhus University, 8000, Aarhus, Denmark
| | - Niels Sandal
- Department of Molecular Biology and Genetics, Aarhus University, 8000, Aarhus, Denmark
| | - Akio Miyao
- Institute of Crop Science, National Agriculture and Food Research Organization, 2-1-2, Kannondai, Tsukuba, Ibaraki, 305-8518, Japan
| | - Seijiro Ono
- Plant Cytogenetics, Department of Gene Function and Phenomics, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540, Japan
| | - Hideki Hirakawa
- Department of Technology Development, Kazusa DNA Research Institute, Kisarazu, Chiba, 292-0818, Japan
| | - Turgut Yigit Akyol
- Department of Molecular Biology and Genetics, Aarhus University, 8000, Aarhus, Denmark
| | - Yosuke Umehara
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2, Oowashi, Tsukuba, Ibaraki, 305-8634, Japan
| | - Ken-Ichi Nonomura
- Department of Technology Development, Kazusa DNA Research Institute, Kisarazu, Chiba, 292-0818, Japan
| | - Jens Stougaard
- Department of Molecular Biology and Genetics, Aarhus University, 8000, Aarhus, Denmark
| | - Hirohiko Hirochika
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2, Oowashi, Tsukuba, Ibaraki, 305-8634, Japan
| | - Makoto Hayashi
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2, Oowashi, Tsukuba, Ibaraki, 305-8634, Japan
- Center for Sustainable Resource Science, RIKEN, Yokohama, Kanagawa, 230-0045, Japan
| | - Shusei Sato
- Department of Technology Development, Kazusa DNA Research Institute, Kisarazu, Chiba, 292-0818, Japan
- Graduate School of Life Sciences, Tohoku University, Katahira, Aoba-ku, Sendai, Miyagi, 980-8577, Japan
| | | | - Keiichi Okazaki
- Graduate School of Science and Technology, Niigata University, Ikarashi-ninocho, 950-2181, Niigata, Japan
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12
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Rozov SM, Permyakova NV, Sidorchuk YV, Deineko EV. Optimization of Genome Knock-In Method: Search for the Most Efficient Genome Regions for Transgene Expression in Plants. Int J Mol Sci 2022; 23:ijms23084416. [PMID: 35457234 PMCID: PMC9027324 DOI: 10.3390/ijms23084416] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/01/2022] [Accepted: 04/14/2022] [Indexed: 02/04/2023] Open
Abstract
Plant expression systems are currently regarded as promising alternative platforms for the production of recombinant proteins, including the proteins for biopharmaceutical purposes. However, the accumulation level of a target protein in plant expression systems is still rather low compared with the other existing systems, namely, mammalian, yeast, and E. coli cells. To solve this problem, numerous methods and approaches have been designed and developed. At the same time, the random nature of the distribution of transgenes over the genome can lead to gene silencing, variability in the accumulation of recombinant protein, and also to various insertional mutations. The current research study considered inserting target genes into pre-selected regions of the plant genome (genomic “safe harbors”) using the CRISPR/Cas system. Regions of genes expressed constitutively and at a high transcriptional level in plant cells (housekeeping genes) that are of interest as attractive targets for the delivery of target genes were characterized. The results of the first attempts to deliver target genes to the regions of housekeeping genes are discussed. The approach of “euchromatization” of the transgene integration region using the modified dCas9 associated with transcription factors is considered. A number of the specific features in the spatial chromatin organization allowing individual genes to efficiently transcribe are discussed.
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13
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Shim S, Lee HG, Park OS, Shin H, Lee K, Lee H, Huh JH, Seo PJ. Dynamic changes in DNA methylation occur in TE regions and affect cell proliferation during leaf-to-callus transition in Arabidopsis. Epigenetics 2022; 17:41-58. [PMID: 33406971 PMCID: PMC8812807 DOI: 10.1080/15592294.2021.1872927] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 12/07/2020] [Accepted: 12/28/2020] [Indexed: 12/13/2022] Open
Abstract
Plant somatic cells can be reprogrammed into pluripotent cell mass, called callus, through a two-step in vitro tissue culture method. Incubation on callus-inducing medium triggers active cell proliferation to form a pluripotent callus. Notably, DNA methylation is implicated during callus formation, but a detailed molecular process regulated by DNA methylation remains to be fully elucidated. Here, we compared genome-wide DNA methylation profiles between leaf and callus tissues in Arabidopsis using whole-genome bisulphite-sequencing. Global distribution of DNA methylation showed that CHG methylation was increased, whereas CHH methylation was reduced especially around transposable element (TE) regions during the leaf-to-callus transition. We further analysed differentially expressed genes around differentially methylated TEs (DMTEs) during the leaf-to-callus transition and found that genes involved in cell cycle regulation were enriched and also constituted a coexpression gene network along with pluripotency regulators. In addition, a conserved DNA sequence analysis for upstream cis-elements led us to find a putative transcription factor associated with cell fate transition. CIRCADIAN CLOCK-ASSOCIATED 1 (CCA1) was newly identified as a regulator of plant regeneration, and consistently, the cca1lhy mutant displayed altered phenotypes in callus proliferation. Overall, these results suggest that DNA methylation coordinates cell cycle regulation during callus formation, and CCA1 may act as a key upstream coordinator at least in part in the processes.
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Affiliation(s)
- Sangrea Shim
- Department of Chemistry, Seoul National University, Seoul, Korea
- Plant Genomics and Breeding Institute, Seoul National University, Seoul, Korea
| | - Hong Gil Lee
- Department of Chemistry, Seoul National University, Seoul, Korea
- Plant Genomics and Breeding Institute, Seoul National University, Seoul, Korea
| | - Ok-Sun Park
- Research Institute of Basic Sciences, Seoul National University, Seoul, Korea
| | - Hosub Shin
- Department of Agriculture, Forestry and Bioresources, Seoul National University, Seoul, Korea
| | - Kyounghee Lee
- Research Institute of Basic Sciences, Seoul National University, Seoul, Korea
| | - Hongwoo Lee
- Department of Chemistry, Seoul National University, Seoul, Korea
| | - Jin Hoe Huh
- Plant Genomics and Breeding Institute, Seoul National University, Seoul, Korea
- Department of Agriculture, Forestry and Bioresources, Seoul National University, Seoul, Korea
| | - Pil Joon Seo
- Department of Chemistry, Seoul National University, Seoul, Korea
- Plant Genomics and Breeding Institute, Seoul National University, Seoul, Korea
- Research Institute of Basic Sciences, Seoul National University, Seoul, Korea
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14
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Harnessing epigenetic variability for crop improvement: current status and future prospects. Genes Genomics 2021; 44:259-266. [PMID: 34807374 DOI: 10.1007/s13258-021-01189-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 11/07/2021] [Indexed: 10/19/2022]
Abstract
BACKGROUND The epigenetic mechanisms play critical roles in a vast diversity of biological processes of plants, including development and response to environmental challenges. Particularly, DNA methylation is a stable epigenetic signature that supplements the genetics-based view of complex life phenomena. In crop breeding, the decrease in genetic diversity due to artificial selection of conventional breeding methods has been a long-standing concern. Therefore, the epigenetic diversity has been proposed as a new resource for future crop breeding, which will be hereinafter referred to as epibreeding. DISCUSSION The induction of methylome changes has been performed in plants by several methods including chemical drugs treatment and tissue culture. Target-specific epigenetic engineering has been also attempted by exogenous RNAi mediated by virus-induced gene silencing and grafting. Importantly, the new and innovative techniques including the CRISPR-Cas9 system have recently been adopted in epigenetic engineering of plant genomes, facilitating the efforts for epibreeding. CONCLUSION In this review, we introduce several examples of natural and induced epigenetic changes impacting on agronomic traits and discuss the methods for generating epigenomic diversity and site-specific epigenetic engineering.
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15
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Lizamore D, Bicknell R, Winefield C. Elevated transcription of transposable elements is accompanied by het-siRNA-driven de novo DNA methylation in grapevine embryogenic callus. BMC Genomics 2021; 22:676. [PMID: 34544372 PMCID: PMC8454084 DOI: 10.1186/s12864-021-07973-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 09/03/2021] [Indexed: 11/10/2022] Open
Abstract
Background Somatic variation is a valuable source of trait diversity in clonally propagated crops. In grapevine, which has been clonally propagated worldwide for centuries, important phenotypes such as white berry colour are the result of genetic changes caused by transposable elements. Additionally, epiallele formation may play a role in determining geo-specific (‘terroir’) differences in grapes and thus ultimately in wine. This genomic plasticity might be co-opted for crop improvement via somatic embryogenesis, but that depends on a species-specific understanding of the epigenetic regulation of transposable element (TE) expression and silencing in these cultures. For this reason, we used whole-genome bisulphite sequencing, mRNA sequencing and small RNA sequencing to study the epigenetic status and expression of TEs in embryogenic callus, in comparison with leaf tissue. Results We found that compared with leaf tissue, grapevine embryogenic callus cultures accumulate relatively high genome-wide CHH methylation, particularly across heterochromatic regions. This de novo methylation is associated with an abundance of transcripts from highly replicated TE families, as well as corresponding 24 nt heterochromatic siRNAs. Methylation in the TE-specific CHG context was relatively low over TEs located within genes, and the expression of TE loci within genes was highly correlated with the expression of those genes. Conclusions This multi-‘omics analysis of grapevine embryogenic callus in comparison with leaf tissues reveals a high level of genome-wide transcription of TEs accompanied by RNA-dependent DNA methylation of these sequences in trans. This provides insight into the genomic conditions underlying somaclonal variation and epiallele formation in plants regenerated from embryogenic cultures, which is an important consideration when using these tissues for plant propagation and genetic improvement. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07973-9.
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Affiliation(s)
| | - Ross Bicknell
- Plant and Food Research Ltd, Lincoln, Canterbury, New Zealand
| | - Chris Winefield
- Department Wine, Food and Molecular Biosciences, Lincoln University, Canterbury, New Zealand.
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16
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Dalakouras A, Vlachostergios D. Epigenetic approaches to crop breeding: current status and perspectives. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:5356-5371. [PMID: 34017985 DOI: 10.1093/jxb/erab227] [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: 03/18/2021] [Accepted: 05/18/2021] [Indexed: 05/10/2023]
Abstract
In order to tackle the cumulative adverse effects of global climate change, reduced farmland, and heightened needs of an ever-increasing world population, modern agriculture is in urgent search of solutions that can ensure world food security and sustainable development. Classical crop breeding is still a powerful method to obtain crops with valued agronomical traits, but its potential is gradually being compromised by the menacing decline of genetic variation. Resorting to the epigenome as a source of variation could serve as a promising alternative. Here, we discuss current status of epigenetics-mediated crop breeding (epibreeding), highlight its advances and limitations, outline currently available methodologies, and propose novel RNA-based strategies to modify the epigenome in a gene-specific and transgene-free manner.
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Affiliation(s)
- Athanasios Dalakouras
- Institute of Industrial and Forage Crops, HAO-DEMETER, 41335 Larissa, Greece
- Institute of Plant Breeding and Genetic Resources, HAO-DEMETER, 57001 Thessaloniki, Greece
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17
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Bednarek PT, Pachota KA, Dynkowska WM, Machczyńska J, Orłowska R. Understanding In Vitro Tissue Culture-Induced Variation Phenomenon in Microspore System. Int J Mol Sci 2021; 22:7546. [PMID: 34299165 PMCID: PMC8304781 DOI: 10.3390/ijms22147546] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/24/2021] [Accepted: 07/08/2021] [Indexed: 12/13/2022] Open
Abstract
In vitro tissue culture plant regeneration is a complicated process that requires stressful conditions affecting the cell functioning at multiple levels, including signaling pathways, transcriptome functioning, the interaction between cellular organelles (retro-, anterograde), compounds methylation, biochemical cycles, and DNA mutations. Unfortunately, the network linking all these aspects is not well understood, and the available knowledge is not systemized. Moreover, some aspects of the phenomenon are poorly studied. The present review attempts to present a broad range of aspects involved in the tissue culture-induced variation and hopefully would stimulate further investigations allowing a better understanding of the phenomenon and the cell functioning.
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Affiliation(s)
- Piotr Tomasz Bednarek
- Plant Breeding and Acclimatization Institute—National Research Institute, Radzików, 05-870 Błonie, Poland; (K.A.P.); (W.M.D.); (J.M.); (R.O.)
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18
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Orłowska R, Pachota KA, Dynkowska WM, Niedziela A, Bednarek PT. Androgenic-Induced Transposable Elements Dependent Sequence Variation in Barley. Int J Mol Sci 2021; 22:ijms22136783. [PMID: 34202586 PMCID: PMC8268840 DOI: 10.3390/ijms22136783] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/14/2021] [Accepted: 06/22/2021] [Indexed: 01/10/2023] Open
Abstract
A plant genome usually encompasses different families of transposable elements (TEs) that may constitute up to 85% of nuclear DNA. Under stressful conditions, some of them may activate, leading to sequence variation. In vitro plant regeneration may induce either phenotypic or genetic and epigenetic changes. While DNA methylation alternations might be related, i.e., to the Yang cycle problems, DNA pattern changes, especially DNA demethylation, may activate TEs that could result in point mutations in DNA sequence changes. Thus, TEs have the highest input into sequence variation (SV). A set of barley regenerants were derived via in vitro anther culture. High Performance Liquid Chromatography (RP-HPLC), used to study the global DNA methylation of donor plants and their regenerants, showed that the level of DNA methylation increased in regenerants by 1.45% compared to the donors. The Methyl-Sensitive Transposon Display (MSTD) based on methylation-sensitive Amplified Fragment Length Polymorphism (metAFLP) approach demonstrated that, depending on the selected elements belonging to the TEs family analyzed, varying levels of sequence variation were evaluated. DNA sequence contexts may have a different impact on SV generated by distinct mobile elements belonged to various TE families. Based on the presented study, some of the selected mobile elements contribute differently to TE-related SV. The surrounding context of the TEs DNA sequence is possibly important here, and the study explained some part of SV related to those contexts.
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19
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Baduel P, Colot V. The epiallelic potential of transposable elements and its evolutionary significance in plants. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200123. [PMID: 33866816 PMCID: PMC8059525 DOI: 10.1098/rstb.2020.0123] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
DNA provides the fundamental framework for heritability, yet heritable trait variation need not be completely ‘hard-wired’ into the DNA sequence. In plants, the epigenetic machinery that controls transposable element (TE) activity, and which includes DNA methylation, underpins most known cases of inherited trait variants that are independent of DNA sequence changes. Here, we review our current knowledge of the extent, mechanisms and potential adaptive contribution of epiallelic variation at TE-containing alleles in this group of species. For the purpose of this review, we focus mainly on DNA methylation, as it provides an easily quantifiable readout of such variation. The picture that emerges is complex. On the one hand, pronounced differences in DNA methylation at TE sequences can either occur spontaneously or be induced experimentally en masse across the genome through genetic means. Many of these epivariants are stably inherited over multiple sexual generations, thus leading to transgenerational epigenetic inheritance. Functional consequences can be significant, yet they are typically of limited magnitude and although the same epivariants can be found in nature, the factors involved in their generation in this setting remain to be determined. On the other hand, moderate DNA methylation variation at TE-containing alleles can be reproducibly induced by the environment, again usually with mild effects, and most of this variation tends to be lost across generations. Based on these considerations, we argue that TE-containing alleles, rather than their inherited epiallelic variants, are the main targets of natural selection. Thus, we propose that the adaptive contribution of TE-associated epivariation, whether stable or not, lies predominantly in its capacity to modulate TE mobilization in response to the environment, hence providing hard-wired opportunities for the flexible exploration of the phenotypic space. This article is part of the theme issue ‘How does epigenetics influence the course of evolution?’
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Affiliation(s)
- Pierre Baduel
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Ecole Normale Supérieure, PSL Research University, 75005 Paris, France
| | - Vincent Colot
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Ecole Normale Supérieure, PSL Research University, 75005 Paris, France
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20
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Papareddy RK, Nodine MD. Plant Epigenetics: Propelling DNA Methylation Variation across the Cell Cycle. Curr Biol 2021; 31:R129-R131. [PMID: 33561411 DOI: 10.1016/j.cub.2020.11.049] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
DNA methylation is reconfigured during male reproduction in plants, but little is known regarding the mechanisms controlling these epigenetic dynamics. New research highlights how the cell cycle can influence DNA methylation dynamics observed during male gametogenesis and may induce epigenetic variation in clonally propagated plants.
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Affiliation(s)
- Ranjith K Papareddy
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria.
| | - Michael D Nodine
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria.
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21
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Borges F, Donoghue MTA, LeBlanc C, Wear EE, Tanurdžić M, Berube B, Brooks A, Thompson WF, Hanley-Bowdoin L, Martienssen RA. Loss of Small-RNA-Directed DNA Methylation in the Plant Cell Cycle Promotes Germline Reprogramming and Somaclonal Variation. Curr Biol 2020; 31:591-600.e4. [PMID: 33275892 DOI: 10.1016/j.cub.2020.10.098] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/24/2020] [Accepted: 10/30/2020] [Indexed: 02/07/2023]
Abstract
5-methyl cytosine is widespread in plant genomes in both CG and non-CG contexts. During replication, hemi-methylation on parental DNA strands guides symmetric CG methylation on nascent strands, but non-CG methylation requires modified histones and small RNA guides. Here, we used immortalized Arabidopsis cell suspensions to sort replicating nuclei and determine genome-wide cytosine methylation dynamics during the plant cell cycle. We find that symmetric mCG and mCHG are selectively retained in actively dividing cells in culture, whereas mCHH is depleted. mCG becomes transiently asymmetric during S phase but is rapidly restored in G2, whereas mCHG remains asymmetric throughout the cell cycle. Hundreds of loci gain ectopic CHG methylation, as well as 24-nt small interfering RNAs (siRNAs) and histone H3 lysine dimethylation (H3K9me2), without gaining CHH methylation. This suggests that spontaneous epialleles that arise in plant cell cultures are stably maintained by siRNA and H3K9me2 independent of the canonical RNA-directed DNA methylation (RdDM) pathway. In contrast, loci that fail to produce siRNA may be targeted for demethylation when the cell cycle arrests. Comparative analysis with methylomes of various tissues and cell types suggests that loss of small-RNA-directed non-CG methylation during DNA replication promotes germline reprogramming and epigenetic variation in plants propagated as clones.
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Affiliation(s)
- Filipe Borges
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA; Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France
| | - Mark T A Donoghue
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Chantal LeBlanc
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Emily E Wear
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Milos Tanurdžić
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Benjamin Berube
- Cold Spring Harbor Laboratory School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Ashley Brooks
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - William F Thompson
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Linda Hanley-Bowdoin
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Robert A Martienssen
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.
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22
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Wear EE, Song J, Zynda GJ, Mickelson-Young L, LeBlanc C, Lee TJ, Deppong DO, Allen GC, Martienssen RA, Vaughn MW, Hanley-Bowdoin L, Thompson WF. Comparing DNA replication programs reveals large timing shifts at centromeres of endocycling cells in maize roots. PLoS Genet 2020; 16:e1008623. [PMID: 33052904 PMCID: PMC7588055 DOI: 10.1371/journal.pgen.1008623] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 10/26/2020] [Accepted: 08/28/2020] [Indexed: 12/20/2022] Open
Abstract
Plant cells undergo two types of cell cycles–the mitotic cycle in which DNA replication is coupled to mitosis, and the endocycle in which DNA replication occurs in the absence of cell division. To investigate DNA replication programs in these two types of cell cycles, we pulse labeled intact root tips of maize (Zea mays) with 5-ethynyl-2’-deoxyuridine (EdU) and used flow sorting of nuclei to examine DNA replication timing (RT) during the transition from a mitotic cycle to an endocycle. Comparison of the sequence-based RT profiles showed that most regions of the maize genome replicate at the same time during S phase in mitotic and endocycling cells, despite the need to replicate twice as much DNA in the endocycle and the fact that endocycling is typically associated with cell differentiation. However, regions collectively corresponding to 2% of the genome displayed significant changes in timing between the two types of cell cycles. The majority of these regions are small with a median size of 135 kb, shift to a later RT in the endocycle, and are enriched for genes expressed in the root tip. We found larger regions that shifted RT in centromeres of seven of the ten maize chromosomes. These regions covered the majority of the previously defined functional centromere, which ranged between 1 and 2 Mb in size in the reference genome. They replicate mainly during mid S phase in mitotic cells but primarily in late S phase of the endocycle. In contrast, the immediately adjacent pericentromere sequences are primarily late replicating in both cell cycles. Analysis of CENH3 enrichment levels in 8C vs 2C nuclei suggested that there is only a partial replacement of CENH3 nucleosomes after endocycle replication is complete. The shift to later replication of centromeres and possible reduction in CENH3 enrichment after endocycle replication is consistent with a hypothesis that centromeres are inactivated when their function is no longer needed. In traditional cell division, or mitosis, a cell’s genetic material is duplicated and then split between two daughter cells. In contrast, in some specialized cell types, the DNA is duplicated a second time without an intervening division step, resulting in cells that carry twice as much DNA. This phenomenon, which is called the endocycle, is common during plant development. At each step, DNA replication follows an ordered program in which highly compacted DNA is unraveled and replicated in sections at different times during the synthesis (S) phase. In plants, it is unclear whether traditional and endocycle programs are the same, especially since endocycling cells are typically in the process of differentiation. Using root tips of maize, we found that in comparison to replication in the mitotic cell cycle, there is a small portion of the genome whose replication in the endocycle is shifted in time, usually to later in S phase. Some of these regions are scattered around the genome and mostly coincide with active genes. However, the most prominent shifts occur in centromeres. The shift to later replication in centromeres is noteworthy because they orchestrate the process of separating duplicated chromosomes into daughter cells, a function that is not needed in the endocycle.
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Affiliation(s)
- Emily E. Wear
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, United States of America
- * E-mail:
| | - Jawon Song
- Texas Advanced Computing Center, University of Texas, Austin, Texas, United States of America
| | - Gregory J. Zynda
- Texas Advanced Computing Center, University of Texas, Austin, Texas, United States of America
| | - Leigh Mickelson-Young
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Chantal LeBlanc
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Tae-Jin Lee
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, United States of America
| | - David O. Deppong
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, United States of America
| | - George C. Allen
- Department of Horticultural Science, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Robert A. Martienssen
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Matthew W. Vaughn
- Texas Advanced Computing Center, University of Texas, Austin, Texas, United States of America
| | - Linda Hanley-Bowdoin
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, United States of America
| | - William F. Thompson
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, United States of America
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23
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Sarpan N, Taranenko E, Ooi SE, Low ETL, Espinoza A, Tatarinova TV, Ong-Abdullah M. DNA methylation changes in clonally propagated oil palm. PLANT CELL REPORTS 2020; 39:1219-1233. [PMID: 32591850 DOI: 10.1007/s00299-020-02561-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 06/17/2020] [Indexed: 06/11/2023]
Abstract
Several hypomethylated sites within the Karma region of EgDEF1 and hotspot regions in chromosomes 1, 2, 3, and 5 may be associated with mantling. One of the main challenges faced by the oil palm industry is fruit abnormalities, such as the "mantled" phenotype that can lead to reduced yields. This clonal abnormality is an epigenetic phenomenon and has been linked to the hypomethylation of a transposable element within the EgDEF1 gene. To understand the epigenome changes in clones, methylomes of clonal oil palms were compared to methylomes of seedling-derived oil palms. Whole-genome bisulfite sequencing data from seedlings, normal, and mantled clones were analyzed to determine and compare the context-specific DNA methylomes. In seedlings, coding and regulatory regions are generally hypomethylated while introns and repeats are extensively methylated. Genes with a low number of guanines and cytosines in the third position of codons (GC3-poor genes) were increasingly methylated towards their 3' region, while GC3-rich genes remain demethylated, similar to patterns in other eukaryotic species. Predicted promoter regions were generally hypomethylated in seedlings. In clones, CG, CHG, and CHH methylation levels generally decreased in functionally important regions, such as promoters, 5' UTRs, and coding regions. Although random regions were found to be hypomethylated in clonal genomes, hypomethylation of certain hotspot regions may be associated with the clonal mantling phenotype. Our findings, therefore, suggest other hypomethylated CHG sites within the Karma of EgDEF1 and hypomethylated hotspot regions in chromosomes 1, 2, 3 and 5, are associated with mantling.
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Affiliation(s)
- Norashikin Sarpan
- Advanced Biotechnology and Breeding Centre, Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | - Elizaveta Taranenko
- Department of Biology, University of La Verne, La Verne, CA, USA
- Department of Fundamental Biology and Biotechnology, Siberian Federal University, 660074, Krasnoyarsk, Russia
| | - Siew-Eng Ooi
- Advanced Biotechnology and Breeding Centre, Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | - Eng-Ti Leslie Low
- Advanced Biotechnology and Breeding Centre, Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | | | - Tatiana V Tatarinova
- Department of Biology, University of La Verne, La Verne, CA, USA.
- Department of Fundamental Biology and Biotechnology, Siberian Federal University, 660074, Krasnoyarsk, Russia.
- Vavilov Institute for General Genetics, Moscow, Russia.
- A.A. Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russia.
| | - Meilina Ong-Abdullah
- Advanced Biotechnology and Breeding Centre, Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia.
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Quadrana L. The contribution of transposable elements to transcriptional novelty in plants: the FLC affair. Transcription 2020; 11:192-198. [PMID: 32783496 PMCID: PMC7714446 DOI: 10.1080/21541264.2020.1803031] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Transposable elements (TEs) are repetitive DNA sequences with the ability to replicate across genomes and generate mutations with major transcriptional effects. Epigenetic silencing mechanisms that target TEs to limit their activity, including DNA methylation, add to the range of gene expression variants generated by TEs. Here, using the iconic gene flowering locus C (FLC) as a case study I discuss the multiple ways by which TEs can affect the expression of genes and contribute to the adaptation of plants to changing environments
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Affiliation(s)
- Leandro Quadrana
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Ecole Normale Supérieure, PSL Research University , Paris, France
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25
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Bednarek PT, Zebrowski J, Orłowska R. Exploring the Biochemical Origin of DNA Sequence Variation in Barley Plants Regenerated via in Vitro Anther Culture. Int J Mol Sci 2020; 21:E5770. [PMID: 32796744 PMCID: PMC7461140 DOI: 10.3390/ijms21165770] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/06/2020] [Accepted: 08/10/2020] [Indexed: 12/14/2022] Open
Abstract
Tissue culture is an essential tool for the regeneration of uniform plant material. However, tissue culture conditions can be a source of abiotic stress for plants, leading to changes in the DNA sequence and methylation patterns. Despite the growing evidence on biochemical processes affected by abiotic stresses, how these altered biochemical processes affect DNA sequence and methylation patterns remains largely unknown. In this study, the methylation-sensitive Amplified Fragment Length Polymorphism (metAFLP) approach was used to investigate de novo methylation, demethylation, and sequence variation in barley regenerants derived by anther culture. Additionally, we used Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy to identify the spectral features of regenerants, which were then analyzed by mediation analysis. The infrared spectrum ranges (710-690 and 1010-940 cm-1) identified as significant in the mediation analysis were most likely related to β-glucans, cellulose, and S-adenosyl-L-methionine (SAM). Additionally, the identified compounds participated as predictors in moderated mediation analysis, explaining the role of demethylation of CHG sites (CHG_DMV) in in vitro tissue culture-induced sequence variation, depending on the duration of tissue culture. The data demonstrate that ATR-FTIR spectroscopy is a useful tool for studying the biochemical compounds that may affect DNA methylation patterns and sequence variation, if combined with quantitative characteristics determined using metAFLP molecular markers and mediation analysis. The role of β-glucans, cellulose, and SAM in DNA methylation, and in cell wall, mitochondria, and signaling, are discussed to highlight the putative cellular mechanisms involved in sequence variation.
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Affiliation(s)
- Piotr T. Bednarek
- Department of Plant Physiology and Biochemistry, Plant Breeding and Acclimatization Institute—National Research Institute, Radzików, 05-870 Błonie, Poland;
| | - Jacek Zebrowski
- Institute of Biology and Biotechnology, University of Rzeszow, Al. Rejtana 16c A, 35-959 Rzeszow, Poland;
| | - Renata Orłowska
- Department of Plant Physiology and Biochemistry, Plant Breeding and Acclimatization Institute—National Research Institute, Radzików, 05-870 Błonie, Poland;
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Bidabadi SS, Jain SM. Cellular, Molecular, and Physiological Aspects of In Vitro Plant Regeneration. PLANTS (BASEL, SWITZERLAND) 2020; 9:E702. [PMID: 32492786 PMCID: PMC7356144 DOI: 10.3390/plants9060702] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 05/25/2020] [Accepted: 05/27/2020] [Indexed: 02/07/2023]
Abstract
Plants generally have the highest regenerative ability because they show a high degree of developmental plasticity. Although the basic principles of plant regeneration date back many years, understanding the cellular, molecular, and physiological mechanisms based on these principles is currently in progress. In addition to the significant effects of some factors such as medium components, phytohormones, explant type, and light on the regeneration ability of an explant, recent reports evidence the involvement of molecular signals in organogenesis and embryogenesis responses to explant wounding, induced plant cell death, and phytohormones interaction. However, some cellular behaviors such as the occurrence of somaclonal variations and abnormalities during the in vitro plant regeneration process may be associated with adverse effects on the efficacy of plant regeneration. A review of past studies suggests that, in some cases, regeneration in plants involves the reprogramming of distinct somatic cells, while in others, it is induced by the activation of relatively undifferentiated cells in somatic tissues. However, this review covers the most important factors involved in the process of plant regeneration and discusses the mechanisms by which plants monitor this process.
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Affiliation(s)
- Siamak Shirani Bidabadi
- Department of Horticulture, College of Agriculture, Isfahan University of Technology, Isfahan 84156-83111, Iran;
| | - S. Mohan Jain
- Department of Agricultural Sciences, University of Helsinki, PL-27 Helsinki, Finland
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Azizi P, Hanafi MM, Sahebi M, Harikrishna JA, Taheri S, Yassoralipour A, Nasehi A. Epigenetic changes and their relationship to somaclonal variation: a need to monitor the micropropagation of plantation crops. FUNCTIONAL PLANT BIOLOGY : FPB 2020; 47:508-523. [PMID: 32349860 DOI: 10.1071/fp19077] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 02/23/2020] [Indexed: 06/11/2023]
Abstract
Chromatin modulation plays important roles in gene expression regulation and genome activities. In plants, epigenetic changes, including variations in histone modification and DNA methylation, are linked to alterations in gene expression. Despite the significance and potential of in vitro cell and tissue culture systems in fundamental research and marketable applications, these systems threaten the genetic and epigenetic networks of intact plant organs and tissues. Cell and tissue culture applications can lead to DNA variations, methylation alterations, transposon activation, and finally, somaclonal variations. In this review, we discuss the status of the current understanding of epigenomic changes that occur under in vitro conditions in plantation crops, including coconut, oil palm, rubber, cotton, coffee and tea. It is hoped that comprehensive knowledge of the molecular basis of these epigenomic variations will help researchers develop strategies to enhance the totipotent and embryogenic capabilities of tissue culture systems for plantation crops.
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Affiliation(s)
- Parisa Azizi
- Laboratory of Plantation Science and Technology, Institute of Plantation Studies, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; and Laboratory of Climate-Smart Food Crop Production, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Mohamed M Hanafi
- Laboratory of Plantation Science and Technology, Institute of Plantation Studies, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; and Department of Land Management, Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; and Laboratory of Climate-Smart Food Crop Production, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; and Corresponding author.
| | - Mahbod Sahebi
- Laboratory of Climate-Smart Food Crop Production, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Jennifer A Harikrishna
- Centre of Research in Biotechnology for Agriculture (CEBAR), University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Sima Taheri
- Centre of Research in Biotechnology for Agriculture (CEBAR), University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Ali Yassoralipour
- Department of Agricultural and Food Science, Faculty of Science (Kampar Campus), Universiti Tunku Abdul Rahman (UTAR), Jalan Universiti, Bandar Barat, 31900 Kampar, Perak, Malaysia
| | - Abbas Nasehi
- Laboratory of Plantation Science and Technology, Institute of Plantation Studies, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
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Hu L, Li N, Zhang Z, Meng X, Dong Q, Xu C, Gong L, Liu B. CG hypomethylation leads to complex changes in DNA methylation and transpositional burst of diverse transposable elements in callus cultures of rice. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:188-203. [PMID: 31529551 DOI: 10.1111/tpj.14531] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 09/01/2019] [Accepted: 09/05/2019] [Indexed: 06/10/2023]
Abstract
CG methylation (m CG) is essential for preserving genome stability in mammals, but this link remains obscure in plants. OsMET1-2, a major rice DNA methyltransferase, plays critical roles in maintaining m CG in rice. Null mutation of OsMET1-2 causes massive CG hypomethylation, rendering the mutant suitable to address the role of m CG in maintaining genome integrity in plants. Here, we analyzed m CG dynamics and genome stability in tissue cultures of OsMET1-2 homozygous (-/-) and heterozygous (+/-) mutants, and isogenic wild-type (WT). We found m CG levels in cultures of -/- were substantially lower than in those of WT and +/-, as expected. Unexpectedly, m CG levels in 1- and 3-year cultures of -/- were 77.6% and 48.7% higher, respectively, than in shoot, from which the cultures were initiated, suggesting substantial regain of m CG in -/- cultures, which contrasts to the general trend of m CG loss in all WT plant tissue cultures hitherto studied. Transpositional burst of diverse transposable elements (TEs) occurred only in -/- cultures, although no elevation of genome-wide mutation rate in the form of single nucleotide polymorphisms was detected. Altogether, our results establish an essential role of m CG in retaining TE immobility and hence genome stability in rice and likely in plants in general.
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Affiliation(s)
- Lanjuan Hu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
- College of Plant Sciences, Faculty of Agriculture, Jilin University, Changchun, 130062, China
| | - Ning Li
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Zhibin Zhang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Xinchao Meng
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Qianli Dong
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Chunming Xu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Lei Gong
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Bao Liu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
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Nakamura M, Köhler C, Hennig L. Tissue-specific transposon-associated small RNAs in the gymnosperm tree, Norway spruce. BMC Genomics 2019; 20:997. [PMID: 31856707 PMCID: PMC6923980 DOI: 10.1186/s12864-019-6385-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 12/11/2019] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Small RNAs (sRNAs) are regulatory molecules impacting on gene expression and transposon activity. MicroRNAs (miRNAs) are responsible for tissue-specific and environmentally-induced gene repression. Short interfering RNAs (siRNA) are constitutively involved in transposon silencing across different type of tissues. The male gametophyte in angiosperms has a unique set of sRNAs compared to vegetative tissues, including phased siRNAs from intergenic or genic regions, or epigenetically activated siRNAs. This is contrasted by a lack of knowledge about the sRNA profile of the male gametophyte of gymnosperms. RESULTS Here, we isolated mature pollen from male cones of Norway spruce and investigated its sRNA profiles. While 21-nt sRNAs is the major size class of sRNAs in needles, in pollen 21-nt and 24-nt sRNAs are the most abundant size classes. Although the 24-nt sRNAs were exclusively derived from TEs in pollen, both 21-nt and 24-nt sRNAs were associated with TEs. We also investigated sRNAs from somatic embryonic callus, which has been reported to contain 24-nt sRNAs. Our data show that the 24-nt sRNA profiles are tissue-specific and differ between pollen and cell culture. CONCLUSION Our data reveal that gymnosperm pollen, like angiosperm pollen, has a unique sRNA profile, differing from vegetative leaf tissue. Thus, our results reveal that angiosperm and gymnosperm pollen produce new size classes not present in vegetative tissues; while in angiosperm pollen 21-nt sRNAs are generated, in the gymnosperm Norway spruce 24-nt sRNAs are generated. The tissue-specific production of distinct TE-derived sRNAs in angiosperms and gymnosperms provides insights into the diversification process of sRNAs in TE silencing pathways between the two groups of seed plants.
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Affiliation(s)
- Miyuki Nakamura
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden.
| | - Claudia Köhler
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Lars Hennig
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
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Johannes F, Schmitz RJ. Spontaneous epimutations in plants. THE NEW PHYTOLOGIST 2019; 221:1253-1259. [PMID: 30216456 DOI: 10.1111/nph.15434] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 08/01/2018] [Indexed: 05/22/2023]
Abstract
Contents Summary 1253 I. Introduction 1253 II. What is the rate and molecular spectrum of spontaneous epimutations? 1254 III. Do spontaneous epimutations have phenotypic consequences? 1257 IV. Conclusion and discussion 1258 Acknowledgements 1258 References 1258 SUMMARY: Heritable gains or losses of cytosine methylation can arise stochastically in plant genomes independently of DNA sequence changes. These so-called 'spontaneous epimutations' appear to be a byproduct of imperfect DNA methylation maintenance and epigenome reinforcement events that occur in specialized cell types. There is continued interest in the plant epigenetics community in trying to understand the broader implications of these stochastic events, as some have been shown to induce heritable gene expression changes, shape patterns of methylation diversity within and among plant populations, and appear to be responsive to multi-generational environmental stressors. In this paper we synthesized our current knowledge of the molecular basis and functional consequences of spontaneous epimutations in plants, discuss technical and conceptual challenges, and highlight emerging research directions.
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Affiliation(s)
- Frank Johannes
- Department of Plant Sciences, Technical University of Munich, Liesel-Beckmann-Str. 2, Freising, 85354, Germany
- Institute for Advanced Study (IAS), Technical University of Munich, Lichtenbergstr. 2a, Garching, 85748, Germany
| | - Robert J Schmitz
- Institute for Advanced Study (IAS), Technical University of Munich, Lichtenbergstr. 2a, Garching, 85748, Germany
- Department of Genetics, The University of Georgia, 120 East Green Street, Athens, GA, 30602, USA
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Li J, Wang M, Li Y, Zhang Q, Lindsey K, Daniell H, Jin S, Zhang X. Multi-omics analyses reveal epigenomics basis for cotton somatic embryogenesis through successive regeneration acclimation process. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:435-450. [PMID: 29999579 PMCID: PMC6335067 DOI: 10.1111/pbi.12988] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 07/04/2018] [Accepted: 07/10/2018] [Indexed: 05/20/2023]
Abstract
Plant regeneration via somatic embryogenesis is time-consuming and highly genotype-dependent. The plant somatic embryogenesis process provokes many epigenetics changes including DNA methylation and histone modification. Recently, an elite cotton Jin668, with an extremely high regeneration ability, was developed from its maternal inbred Y668 cultivar using a Successive Regeneration Acclimation (SRA) strategy. To reveal the underlying mechanism of SRA, we carried out a genome-wide single-base resolution methylation analysis for nonembryogenic calluses (NECs), ECs, somatic embryos (SEs) during the somatic embryogenesis procedure and the leaves of regenerated offspring plants. Jin668 (R4) regenerated plants were CHH hypomethylated compared with the R0 regenerated plants of SRA process. The increase in CHH methylation from NEC to EC was demonstrated to be associated with the RNA-dependent DNA methylation (RdDM) and the H3K9me2-dependent pathway. Intriguingly, the hypomethylated CHH differentially methylated regions (DMRs) of promoter activated some hormone-related and WUSCHEL-related homeobox genes during the somatic embryogenesis process. Inhibiting DNA methylation using zebularine treatment in NEC increased the number of embryos. Our multi-omics data provide new insights into the dynamics of DNA methylation during the plant tissue culture and regenerated offspring plants. This study also reveals that induced hypomethylation (SRA) may facilitate the higher plant regeneration ability and optimize maternal genetic cultivar.
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Affiliation(s)
- Jianying Li
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Maojun Wang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Yajun Li
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Qinghua Zhang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | | | - Henry Daniell
- Department of BiochemistrySchool of Dental MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA
| | - Shuangxia Jin
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Xianlong Zhang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
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Grativol C, Thiebaut F, Sangi S, Montessoro P, Santos WDS, Hemerly AS, Ferreira PC. A miniature inverted-repeat transposable element, AddIn-MITE, located inside a WD40 gene is conserved in Andropogoneae grasses. PeerJ 2019; 7:e6080. [PMID: 30648010 PMCID: PMC6331000 DOI: 10.7717/peerj.6080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 11/07/2018] [Indexed: 11/25/2022] Open
Abstract
Miniature inverted-repeat transposable elements (MITEs) have been associated with genic regions in plant genomes and may play important roles in the regulation of nearby genes via recruitment of small RNAs (sRNA) to the MITEs loci. We identified eight families of MITEs in the sugarcane genome assembly with MITE-Hunter pipeline. These sequences were found to be upstream, downstream or inserted into 67 genic regions in the genome. The position of the most abundant MITE (Stowaway-like) in genic regions, which we call AddIn-MITE, was confirmed in a WD40 gene. The analysis of four monocot species showed conservation of the AddIn-MITE sequence, with a large number of copies in their genomes. We also investigated the conservation of the AddIn-MITE’ position in the WD40 genes from sorghum, maize and, in sugarcane cultivars and wild Saccharum species. In all analyzed plants, AddIn-MITE has located in WD40 intronic region. Furthermore, the role of AddIn-MITE-related sRNA in WD40 genic region was investigated. We found sRNAs preferentially mapped to the AddIn-MITE than to other regions in the WD40 gene in sugarcane. In addition, the analysis of the small RNA distribution patterns in the WD40 gene and the structure of AddIn-MITE, suggests that the MITE region is a proto-miRNA locus in sugarcane. Together, these data provide insights into the AddIn-MITE role in Andropogoneae grasses.
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Affiliation(s)
- Clicia Grativol
- Laboratório de Química e Função de Proteínas e Peptídeos/Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Flavia Thiebaut
- Laboratório de Biologia Molecular de Plantas/Instituto de Bioquímica Médica Leopoldo De Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Sara Sangi
- Laboratório de Química e Função de Proteínas e Peptídeos/Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Patricia Montessoro
- Laboratório de Biologia Molecular de Plantas/Instituto de Bioquímica Médica Leopoldo De Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Walaci da Silva Santos
- Laboratório de Química e Função de Proteínas e Peptídeos/Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Adriana S. Hemerly
- Laboratório de Biologia Molecular de Plantas/Instituto de Bioquímica Médica Leopoldo De Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paulo C.G. Ferreira
- Laboratório de Biologia Molecular de Plantas/Instituto de Bioquímica Médica Leopoldo De Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
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Partial maintenance of organ-specific epigenetic marks during plant asexual reproduction leads to heritable phenotypic variation. Proc Natl Acad Sci U S A 2018; 115:E9145-E9152. [PMID: 30201727 PMCID: PMC6166847 DOI: 10.1073/pnas.1805371115] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
While clonally propagated individuals should share identical genomes, there is often substantial phenotypic variation among them. Both genetic and epigenetic modifications induced during regeneration have been associated with this phenomenon. Here we investigated the fate of the epigenome after asexual propagation by generating clonal individuals from differentiated somatic cells through the manipulation of a zygotic transcription factor. We found that phenotypic novelty in clonal progeny was linked to epigenetic imprints that reflect the organ used for regeneration. Some of these organ-specific imprints can be maintained during the cloning process and subsequent rounds of meiosis. Our findings are fundamental for understanding the significance of epigenetic variability arising from asexual reproduction and have significant implications for future biotechnological applications. Plants differ from animals in their capability to easily regenerate fertile adult individuals from terminally differentiated cells. This unique developmental plasticity is commonly observed in nature, where many species can reproduce asexually through the ectopic initiation of organogenic or embryogenic developmental programs. While organ-specific epigenetic marks are not passed on during sexual reproduction, the fate of epigenetic marks during asexual reproduction and the implications for clonal progeny remain unclear. Here we report that organ-specific epigenetic imprints in Arabidopsis thaliana can be partially maintained during asexual propagation from somatic cells in which a zygotic program is artificially induced. The altered marks are inherited even over multiple rounds of sexual reproduction, becoming fixed in hybrids and resulting in heritable molecular and physiological phenotypes that depend on the identity of the founder tissue. Consequently, clonal plants display distinct interactions with beneficial and pathogenic microorganisms. Our results demonstrate how novel phenotypic variation in plants can be unlocked through altered inheritance of epigenetic marks upon asexual propagation.
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Heritable Epigenomic Changes to the Maize Methylome Resulting from Tissue Culture. Genetics 2018; 209:983-995. [PMID: 29848487 DOI: 10.1534/genetics.118.300987] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 05/26/2018] [Indexed: 12/22/2022] Open
Abstract
DNA methylation can contribute to the maintenance of genome integrity and regulation of gene expression. In most situations, DNA methylation patterns are inherited quite stably. However, changes in DNA methylation can occur at some loci as a result of tissue culture resulting in somaclonal variation. To investigate heritable epigenetic changes as a consequence of tissue culture, a sequence-capture bisulfite sequencing approach was implemented to monitor context-specific DNA methylation patterns in ∼15 Mb of the maize genome for a population of plants that had been regenerated from tissue culture. Plants that have been regenerated from tissue culture exhibit gains and losses of DNA methylation at a subset of genomic regions. There was evidence for a high rate of homozygous changes to DNA methylation levels that occur consistently in multiple independent tissue culture lines, suggesting that some loci are either targeted or hotspots for epigenetic variation. The consistent changes inherited following tissue culture include both gains and losses of DNA methylation and can affect CG, CHG, or both contexts within a region. Only a subset of the tissue culture changes observed in callus plants are observed in the primary regenerants, but the majority of DNA methylation changes present in primary regenerants are passed onto offspring. This study provides insights into the susceptibility of some loci and potential mechanisms that could contribute to altered DNA methylation and epigenetic state that occur during tissue culture in plant species.
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Lee K, Seo PJ. Dynamic Epigenetic Changes during Plant Regeneration. TRENDS IN PLANT SCIENCE 2018; 23:235-247. [PMID: 29338924 DOI: 10.1016/j.tplants.2017.11.009] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 11/28/2017] [Accepted: 11/29/2017] [Indexed: 05/18/2023]
Abstract
Plants have the remarkable ability to drive cellular dedifferentiation and regeneration. Changes in epigenetic landscapes accompany the cell fate transition. Notably, modifications of chromatin structure occur primarily during callus formation via an in vitro tissue culture process and, thus, pluripotent callus cells have unique epigenetic signatures. Here, we highlight the latest progress in epigenetic regulation of callus formation in plants, which addresses fundamental questions related to cell fate changes and pluripotency establishment. Global and local modifications of chromatin structure underlie callus formation, and the combination and sequence of epigenetic modifications further shape intricate cell fate changes. This review illustrates how a series of chromatin marks change dynamically during callus formation and their biological relevance in plant regeneration.
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Affiliation(s)
- Kyounghee Lee
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Pil Joon Seo
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea.
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36
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Vergara Z, Sequeira-Mendes J, Morata J, Peiró R, Hénaff E, Costas C, Casacuberta JM, Gutierrez C. Retrotransposons are specified as DNA replication origins in the gene-poor regions of Arabidopsis heterochromatin. Nucleic Acids Res 2017; 45:8358-8368. [PMID: 28605523 PMCID: PMC5737333 DOI: 10.1093/nar/gkx524] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 06/05/2017] [Indexed: 12/28/2022] Open
Abstract
Genomic stability depends on faithful genome replication. This is achieved by the concerted activity of thousands of DNA replication origins (ORIs) scattered throughout the genome. The DNA and chromatin features determining ORI specification are not presently known. We have generated a high-resolution genome-wide map of 3230 ORIs in cultured Arabidopsis thaliana cells. Here, we focused on defining the features associated with ORIs in heterochromatin. In pericentromeric gene-poor domains ORIs associate almost exclusively with the retrotransposon class of transposable elements (TEs), in particular of the Gypsy family. ORI activity in retrotransposons occurs independently of TE expression and while maintaining high levels of H3K9me2 and H3K27me1, typical marks of repressed heterochromatin. ORI-TEs largely colocalize with chromatin signatures defining GC-rich heterochromatin. Importantly, TEs with active ORIs contain a local GC content higher than the TEs lacking them. Our results lead us to conclude that ORI colocalization with retrotransposons is determined by their transposition mechanism based on transcription, and a specific chromatin landscape. Our detailed analysis of ORIs responsible for heterochromatin replication has implications on the mechanisms of ORI specification in other multicellular organisms in which retrotransposons are major components of heterochromatin and of the entire genome.
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Affiliation(s)
- Zaida Vergara
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Nicolás Cabrera 1, Cantoblanco, 28049 Madrid, Spain
| | - Joana Sequeira-Mendes
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Nicolás Cabrera 1, Cantoblanco, 28049 Madrid, Spain
| | - Jordi Morata
- Center for Research in Agricultural Genomics, CRAG (CSIC-IRTA-UAB-UB), Campus Universitat Autónoma de Barcelona, Bellaterra, Cerdanyola del Valles, 08193 Barcelona, Spain
| | - Ramón Peiró
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Nicolás Cabrera 1, Cantoblanco, 28049 Madrid, Spain
| | - Elizabeth Hénaff
- Center for Research in Agricultural Genomics, CRAG (CSIC-IRTA-UAB-UB), Campus Universitat Autónoma de Barcelona, Bellaterra, Cerdanyola del Valles, 08193 Barcelona, Spain
| | - Celina Costas
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Nicolás Cabrera 1, Cantoblanco, 28049 Madrid, Spain
| | - Josep M Casacuberta
- Center for Research in Agricultural Genomics, CRAG (CSIC-IRTA-UAB-UB), Campus Universitat Autónoma de Barcelona, Bellaterra, Cerdanyola del Valles, 08193 Barcelona, Spain
| | - Crisanto Gutierrez
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Nicolás Cabrera 1, Cantoblanco, 28049 Madrid, Spain
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Pass DA, Sornay E, Marchbank A, Crawford MR, Paszkiewicz K, Kent NA, Murray JAH. Genome-wide chromatin mapping with size resolution reveals a dynamic sub-nucleosomal landscape in Arabidopsis. PLoS Genet 2017; 13:e1006988. [PMID: 28902852 PMCID: PMC5597176 DOI: 10.1371/journal.pgen.1006988] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 08/21/2017] [Indexed: 02/06/2023] Open
Abstract
All eukaryotic genomes are packaged as chromatin, with DNA interlaced with both regularly patterned nucleosomes and sub-nucleosomal-sized protein structures such as mobile and labile transcription factors (TF) and initiation complexes, together forming a dynamic chromatin landscape. Whilst details of nucleosome position in Arabidopsis have been previously analysed, there is less understanding of their relationship to more dynamic sub-nucleosomal particles (subNSPs) defined as protected regions shorter than the ~150bp typical of nucleosomes. The genome-wide profile of these subNSPs has not been previously analysed in plants and this study investigates the relationship of dynamic bound particles with transcriptional control. Here we combine differential micrococcal nuclease (MNase) digestion and a modified paired-end sequencing protocol to reveal the chromatin structure landscape of Arabidopsis cells across a wide particle size range. Linking this data to RNAseq expression analysis provides detailed insight into the relationship of identified DNA-bound particles with transcriptional activity. The use of differential digestion reveals sensitive positions, including a labile -1 nucleosome positioned upstream of the transcription start site (TSS) of active genes. We investigated the response of the chromatin landscape to changes in environmental conditions using light and dark growth, given the large transcriptional changes resulting from this simple alteration. The resulting shifts in the suites of expressed and repressed genes show little correspondence to changes in nucleosome positioning, but led to significant alterations in the profile of subNSPs upstream of TSS both globally and locally. We examined previously mapped positions for the TFs PIF3, PIF4 and CCA1, which regulate light responses, and found that changes in subNSPs co-localized with these binding sites. This small particle structure is detected only under low levels of MNase digestion and is lost on more complete digestion of chromatin to nucleosomes. We conclude that wide-spectrum analysis of the Arabidopsis genome by differential MNase digestion allows detection of sensitive features hereto obscured, and the comparisons between genome-wide subNSP profiles reveals dynamic changes in their distribution, particularly at distinct genomic locations (i.e. 5'UTRs). The method here employed allows insight into the complex influence of genetic and extrinsic factors in modifying the sub-nucleosomal landscape in association with transcriptional changes.
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Affiliation(s)
- Daniel Antony Pass
- Cardiff School of Biosciences, Cardiff University, Cardiff, Wales, United Kingdom
| | - Emily Sornay
- Cardiff School of Biosciences, Cardiff University, Cardiff, Wales, United Kingdom
| | - Angela Marchbank
- Cardiff School of Biosciences, Cardiff University, Cardiff, Wales, United Kingdom
| | - Margaret R. Crawford
- Genome Centre, University of Sussex, Sussex House, Falmer, Brighton, United Kingdom
| | - Konrad Paszkiewicz
- Geoffrey Pope Building, University of Exeter, Stocker Road, Exeter, United Kingdom
| | - Nicholas A. Kent
- Cardiff School of Biosciences, Cardiff University, Cardiff, Wales, United Kingdom
| | - James A. H. Murray
- Cardiff School of Biosciences, Cardiff University, Cardiff, Wales, United Kingdom
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Wear EE, Song J, Zynda GJ, LeBlanc C, Lee TJ, Mickelson-Young L, Concia L, Mulvaney P, Szymanski ES, Allen GC, Martienssen RA, Vaughn MW, Hanley-Bowdoin L, Thompson WF. Genomic Analysis of the DNA Replication Timing Program during Mitotic S Phase in Maize ( Zea mays) Root Tips. THE PLANT CELL 2017; 29:2126-2149. [PMID: 28842533 PMCID: PMC5635974 DOI: 10.1105/tpc.17.00037] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 07/31/2017] [Accepted: 08/24/2017] [Indexed: 05/19/2023]
Abstract
All plants and animals must replicate their DNA, using a regulated process to ensure that their genomes are completely and accurately replicated. DNA replication timing programs have been extensively studied in yeast and animal systems, but much less is known about the replication programs of plants. We report a novel adaptation of the "Repli-seq" assay for use in intact root tips of maize (Zea mays) that includes several different cell lineages and present whole-genome replication timing profiles from cells in early, mid, and late S phase of the mitotic cell cycle. Maize root tips have a complex replication timing program, including regions of distinct early, mid, and late S replication that each constitute between 20 and 24% of the genome, as well as other loci corresponding to ∼32% of the genome that exhibit replication activity in two different time windows. Analyses of genomic, transcriptional, and chromatin features of the euchromatic portion of the maize genome provide evidence for a gradient of early replicating, open chromatin that transitions gradually to less open and less transcriptionally active chromatin replicating in mid S phase. Our genomic level analysis also demonstrated that the centromere core replicates in mid S, before heavily compacted classical heterochromatin, including pericentromeres and knobs, which replicate during late S phase.
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Affiliation(s)
- Emily E Wear
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695
| | - Jawon Song
- Texas Advanced Computing Center, University of Texas, Austin, Texas 78758
| | - Gregory J Zynda
- Texas Advanced Computing Center, University of Texas, Austin, Texas 78758
| | - Chantal LeBlanc
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | - Tae-Jin Lee
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695
| | - Leigh Mickelson-Young
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695
| | - Lorenzo Concia
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695
| | - Patrick Mulvaney
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695
| | - Eric S Szymanski
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695
| | - George C Allen
- Department of Horticultural Science, North Carolina State University, Raleigh, North Carolina 27695
| | | | - Matthew W Vaughn
- Texas Advanced Computing Center, University of Texas, Austin, Texas 78758
| | - Linda Hanley-Bowdoin
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695
| | - William F Thompson
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695
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Markova DN, Mason-Gamer RJ. Transcriptional activity of PIF and Pong-like Class II transposable elements in Triticeae. BMC Evol Biol 2017; 17:178. [PMID: 28774284 PMCID: PMC5543537 DOI: 10.1186/s12862-017-1028-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Accepted: 07/26/2017] [Indexed: 11/10/2022] Open
Abstract
Background Transposable elements are major contributors to genome size and variability, accounting for approximately 70–80% of the maize, barley, and wheat genomes. PIF and Pong-like elements belong to two closely-related element families within the PIF/Harbinger superfamily of Class II (DNA) transposons. Both elements contain two open reading frames; one encodes a transposase (ORF2) that catalyzes transposition of the functional elements and their related non-autonomous elements, while the function of the second is still debated. In this work, we surveyed for PIF- and Pong-related transcriptional activity in 13 diploid Triticeae species, all of which have been previously shown to harbor extensive within-genome diversity of both groups of elements. Results The results revealed that PIF elements have considerable transcriptional activity in Triticeae, suggesting that they can escape the initial levels of plant cell control and are regulated at the post-transcriptional level. Phylogenetic analysis of 156 PIF cDNA transposase fragments along with 240 genomic partial transposase sequences showed that most, if not all, PIF clades are transcriptionally competent, and that multiple transposases coexisting within a single genome have the potential to act simultaneously. In contrast, we did not detect any transcriptional activity of Pong elements in any sample. Conclusions The lack of Pong element transcription shows that even closely related transposon families can exhibit wide variation in their transposase transcriptional activity within the same genome. Electronic supplementary material The online version of this article (doi:10.1186/s12862-017-1028-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Dragomira N Markova
- Department of Biological Sciences, University of Illinois at Chicago, M/C 067 840 West Taylor Street, Chicago, IL, 60607, USA. .,Present address: Department of Plant Sciences (mail stop 3), 151 Asmundson Hall, University of California, Davis, CA, 95616, USA.
| | - Roberta J Mason-Gamer
- Department of Biological Sciences, University of Illinois at Chicago, M/C 067 840 West Taylor Street, Chicago, IL, 60607, USA
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Zakrzewski F, Schmidt M, Van Lijsebettens M, Schmidt T. DNA methylation of retrotransposons, DNA transposons and genes in sugar beet (Beta vulgaris L.). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 90:1156-1175. [PMID: 28257158 DOI: 10.1111/tpj.13526] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/08/2017] [Accepted: 02/09/2017] [Indexed: 05/13/2023]
Abstract
The methylation of cytosines shapes the epigenetic landscape of plant genomes, coordinates transgenerational epigenetic inheritance, represses the activity of transposable elements (TEs), affects gene expression and, hence, can influence the phenotype. Sugar beet (Beta vulgaris ssp. vulgaris), an important crop that accounts for 30% of worldwide sugar needs, has a relatively small genome size (758 Mbp) consisting of approximately 485 Mbp repetitive DNA (64%), in particular satellite DNA, retrotransposons and DNA transposons. Genome-wide cytosine methylation in the sugar beet genome was studied in leaves and leaf-derived callus with a focus on repetitive sequences, including retrotransposons and DNA transposons, the major groups of repetitive DNA sequences, and compared with gene methylation. Genes showed a specific methylation pattern for CG, CHG (H = A, C, and T) and CHH sites, whereas the TE pattern differed, depending on the TE class (class 1, retrotransposons and class 2, DNA transposons). Along genes and TEs, CG and CHG methylation was higher than that of adjacent genomic regions. In contrast to the relatively low CHH methylation in retrotransposons and genes, the level of CHH methylation in DNA transposons was strongly increased, pointing to a functional role of asymmetric methylation in DNA transposon silencing. Comparison of genome-wide DNA methylation between sugar beet leaves and callus revealed a differential methylation upon tissue culture. Potential epialleles were hypomethylated (lower methylation) at CG and CHG sites in retrotransposons and genes and hypermethylated (higher methylation) at CHH sites in DNA transposons of callus when compared with leaves.
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Affiliation(s)
- Falk Zakrzewski
- Department of Biology, Technische Universität Dresden, 01062, Dresden, Germany
| | - Martin Schmidt
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052, Ghent, Belgium
| | - Mieke Van Lijsebettens
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052, Ghent, Belgium
| | - Thomas Schmidt
- Department of Biology, Technische Universität Dresden, 01062, Dresden, Germany
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Fultz D, Slotkin RK. Exogenous Transposable Elements Circumvent Identity-Based Silencing, Permitting the Dissection of Expression-Dependent Silencing. THE PLANT CELL 2017; 29:360-376. [PMID: 28193737 PMCID: PMC5354191 DOI: 10.1105/tpc.16.00718] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 12/19/2016] [Accepted: 02/10/2017] [Indexed: 05/09/2023]
Abstract
The propagation of epigenetic marks has received a great deal of attention, yet the initiation of epigenetic silencing of a new transgene, virus, or transposable element (TE) remains enigmatic. The overlapping and simultaneous function of multiple silencing mechanisms has obscured this area of investigation. Here, we revealed two broad mechanisms that can initiate silencing independently: identity-based and expression-dependent silencing. We found that identity-based silencing is targeted by 21- to 22-nucleotide or 24-nucleotide small interfering RNAs (siRNAs) generated from previously silenced regions of the genome. By transforming exogenous TEs into Arabidopsis thaliana, we circumvented identity-based silencing, allowing us to isolate and investigate the molecular mechanism of expression-dependent silencing. We found that several siRNA-generating mechanisms all trigger de novo expression-dependent RNA-directed DNA methylation (RdDM) through RNA Polymerase V. In addition, while full-length TEs quickly progress beyond RdDM to heterochromatin formation and the final maintenance methylation state, TE fragments stall at the RdDM phase. Lastly, we found that transformation into a mutant genotype followed by introgression into the wild type does not result in the same level of silencing as direct transformation into the wild type. This demonstrates that the plant genotype during a narrow window of time at TE insertion (or transgene transformation) is key for establishing the transgenerational extent of epigenetic silencing.
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Affiliation(s)
- Dalen Fultz
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210
- Molecular, Cellular, and Developmental Biology Graduate Program, The Ohio State University, Columbus, Ohio 43210
| | - R Keith Slotkin
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210
- Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210
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43
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Cirilli M, Delfino I, Caboni E, Muleo R. EpiHRMAssay, in tube and in silico combined approach for the scanning and epityping of heterogeneous DNA methylation. Biol Methods Protoc 2017; 2:bpw008. [PMID: 32161783 PMCID: PMC6994072 DOI: 10.1093/biomethods/bpw008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 11/12/2016] [Accepted: 12/16/2016] [Indexed: 11/18/2022] Open
Abstract
Reliable and cost-effective assays with adequate sensitivity are required to detect the DNA methylation profile in plants for scientific and industrial purposes. The proposed novel assay, named EpiHRMAssay, allows to quantify the overall methylation status at target loci and to enable high-throughput analyses. It combines in tube High Resolution Melting Analysis on bisulphite-treated templates with the in silico prediction of the melting profile of virtual epialleles using uMELTSM software. The predicted melting temperatures (Tm-s) of a set of epialleles characterized by different numbers of methylated cytosines (#mC) or different mC configurations were obtained and used to build calibration models, enabling the quantification of methylation in unknown samples using only the in tube observed melting temperature (Tm-o). EpiHRMAssay was validated by analysing the promoter region of CMT3, DDM1, and ROS1 genes involved in the regulation of methylation/demethylation processes and chromatin remodelling within a population of peach plants. Results demonstrate that EpiHRMAssay is a sensitive and reliable tool for locus-specific large-scale research and diagnostic contexts of the regulative regions of genes, in a broad range of organisms, including mammals. EpiHRMAssay also provides complementary information for the assessment of heterogeneous methylation and can address an array of biological questions on epigenetic regulation for diversity studies and for large-scale functional genomics.
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Affiliation(s)
- Marco Cirilli
- Department of Agricultural and Forestry Sciences, University of Tuscia, Via S. Camillo de Lellis snc, Viterbo 01100, Italy
| | - Ines Delfino
- Department of Ecological and Biological Sciences, University of Tuscia, L.go dell'Università snc, Viterbo 01100, Italy
| | - Emilia Caboni
- Council for Agricultural Research and Analysis of Agricultural Economics (CREA), Fruit Tree Research Center, Via di Fioranello, 52, 00134 Rome, Italy
| | - Rosario Muleo
- Department of Agricultural and Forestry Sciences, University of Tuscia, Via S. Camillo de Lellis snc, Viterbo 01100, Italy
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Ménard D, Serk H, Decou R, Pesquet E. Establishment and Utilization of Habituated Cell Suspension Cultures for Hormone-Inducible Xylogenesis. Methods Mol Biol 2017; 1544:37-57. [PMID: 28050827 DOI: 10.1007/978-1-4939-6722-3_4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The development of inducible cell differentiation in suspension cultures led to multiple breakthroughs. It enabled the understanding of the chronology, duration, regulation and interdependency of the multiple events leading to fully functional specialized cells. The most studied cell differentiation in plants using inducible suspension cultures is the formation of tracheary elements (TEs) - the hydro-mineral sap conducting cells. Several in vitro systems established in different plant species have been developed to trigger TE formation on-demand. Here, we describe the establishment, harvesting and analysis of Arabidopsis thaliana stable habituated cell lines inducible by hormones to differentiate into TEs on-demand. Moreover, we explain the means to monitor and modify the chronology, duration and regulation of the progression of TE formation.
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Affiliation(s)
- Delphine Ménard
- Umeå Plant Science Centre (UPSC), Department of Plant Physiology, Umeå University, 901 87, Umeå, Sweden
- Arrhenius Laboratories, Department of Ecology, Environment and Plant Sciences (DEEP), Svante Arrhenius väg 20A, Stockholm University, 160 91, Stockholm, Sweden
| | - Henrik Serk
- Umeå Plant Science Centre (UPSC), Department of Plant Physiology, Umeå University, 901 87, Umeå, Sweden
- Department of Medical Biochemistry and Biophysics, Umeå University, 901 87, Umeå, Sweden
| | - Raphaël Decou
- Umeå Plant Science Centre (UPSC), Department of Plant Physiology, Umeå University, 901 87, Umeå, Sweden
| | - Edouard Pesquet
- Umeå Plant Science Centre (UPSC), Department of Plant Physiology, Umeå University, 901 87, Umeå, Sweden.
- Arrhenius Laboratories, Department of Ecology, Environment and Plant Sciences (DEEP), Svante Arrhenius väg 20A, Stockholm University, 160 91, Stockholm, Sweden.
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Orłowska R, Machczyńska J, Oleszczuk S, Zimny J, Bednarek PT. DNA methylation changes and TE activity induced in tissue cultures of barley (Hordeum vulgare L.). JOURNAL OF BIOLOGICAL RESEARCH (THESSALONIKE, GREECE) 2016; 23:19. [PMID: 27508170 PMCID: PMC4977862 DOI: 10.1186/s40709-016-0056-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 07/25/2016] [Indexed: 11/10/2022]
Abstract
BACKGROUND In vitro plant regeneration via androgenesis or somatic embryogenesis is capable of inducing (epi)mutations that may affect sexual progenies. While epimutations are associated with DNA methylation, mutations could be due to the movement of transposons. The common notion is that both processes are linked. It is being assumed that demethylation activates transposable elements (TEs). Analysis of methylation changes and their relation with TEs activation in tissue cultures requires uniquely derived donor plants (Ds), their regenerants (Rs) and respective progeny (Ps) that would allow discrimination of processes not related to changes introduced via in vitro cultures. Moreover, a set of methods (RP-HPLC, SSAP, and MSTD) is needed to study whether different TEs families are being activated during in vitro tissue culture plant regeneration and whether their activity could be linked to DNA methylation changes or alternative explanations should be considered. RESULTS The in vitro tissue culture plant regeneration in barley was responsible for the induction of DNA methylation in regenerants and conservation of the methylation level in the progeny as shown by the RP-HPLC approach. No difference between andro- and embryo-derived Rs and Ps was observed. The SSAP and MSTD approach revealed that Ds and Rs were more polymorphic than Ps. Moreover, Rs individuals exhibited more polymorphisms with the MSTD than SSAP approach. The differences between Ds, Rs and Ps were also evaluated via ANOVA and AMOVA. CONCLUSIONS Stressful conditions during plant regeneration via in vitro tissue cultures affect regenerants and their sexual progeny leading to an increase in global DNA methylation of Rs and Ps compared to Ds in barley. The increased methylation level noted among regenerants remains unchanged in the Ps as indicated via RP-HPLC data. Marker-based experiments suggest that TEs are activated via in vitro tissue cultures and that, independently of the increased methylation, their activity in Rs is greater than in Ps. Thus, the increased methylation level may not correspond to the stabilization of TEs movement at least at the level of regenerants. The presence of TEs variation among Ds that were genetically and epigenetically uniform may suggest that at least some mobile elements may be active, and they may mask variation related to tissue cultures. Thus, tissue cultures may activate some TEs whereas the others remain intact, or their level of movement is changed. Finally, we suggest that sexual reproduction may be responsible for the stabilization of TEs.
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Affiliation(s)
- Renata Orłowska
- Department of Plant Physiology and Biochemistry, Plant Breeding and Acclimatization Institute-National Research Institute, Radzików, 05-870 Błonie, Poland
| | - Joanna Machczyńska
- Department of Plant Physiology and Biochemistry, Plant Breeding and Acclimatization Institute-National Research Institute, Radzików, 05-870 Błonie, Poland
| | - Sylwia Oleszczuk
- Department of Plant Biotechnology and Cytogenetics, Plant Breeding and Acclimatization Institute-National Research Institute, Radzików, 05-870 Błonie, Poland
| | - Janusz Zimny
- Department of Plant Biotechnology and Cytogenetics, Plant Breeding and Acclimatization Institute-National Research Institute, Radzików, 05-870 Błonie, Poland
| | - Piotr Tomasz Bednarek
- Department of Plant Physiology and Biochemistry, Plant Breeding and Acclimatization Institute-National Research Institute, Radzików, 05-870 Błonie, Poland
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Affiliation(s)
| | - Vincent Colot
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), F-75005 Paris, France;
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48
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Mickelson-Young L, Wear E, Mulvaney P, Lee TJ, Szymanski ES, Allen G, Hanley-Bowdoin L, Thompson W. A flow cytometric method for estimating S-phase duration in plants. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:6077-6087. [PMID: 27697785 PMCID: PMC5100020 DOI: 10.1093/jxb/erw367] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The duration of the DNA synthesis stage (S phase) of the cell cycle is fundamental in our understanding of cell cycle kinetics, cell proliferation, and DNA replication timing programs. Most S-phase duration estimates that exist for plants are based on indirect measurements. We present a method for directly estimating S-phase duration by pulse-labeling root tips or actively dividing suspension cells with the halogenated thymidine analog 5-ethynl-2'-deoxyuridine (EdU) and analyzing the time course of replication with bivariate flow cytometry. The transition between G1 and G2 DNA contents can be followed by measuring the mean DNA content of EdU-labeled S-phase nuclei as a function of time after the labeling pulse. We applied this technique to intact root tips of maize (Zea mays L.), rice (Oryza sativa L.), barley (Hordeum vulgare L.), and wheat (Triticum aestivum L.), and to actively dividing cell cultures of Arabidopsis (Arabidopsis thaliana (L.) Heynh.) and rice. Estimates of S-phase duration in root tips were remarkably consistent, varying only by ~3-fold, although the genome sizes of the species analyzed varied >40-fold.
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Affiliation(s)
- Leigh Mickelson-Young
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Emily Wear
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Patrick Mulvaney
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Tae-Jin Lee
- Department of Horticultural Science, North Carolina State University, Raleigh, NC 27695, USA
- Present address: Syngenta Crop Protection, LLC, Research Triangle Park, NC 27709, USA
| | - Eric S Szymanski
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
- Present address: Department of Biochemistry, Duke University, Durham, NC 27710, USA
| | - George Allen
- Department of Horticultural Science, North Carolina State University, Raleigh, NC 27695, USA
| | - Linda Hanley-Bowdoin
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - William Thompson
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
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49
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Velanis CN, Herzyk P, Jenkins GI. Regulation of transcription by the Arabidopsis UVR8 photoreceptor involves a specific histone modification. PLANT MOLECULAR BIOLOGY 2016; 92:425-443. [PMID: 27534420 PMCID: PMC5080334 DOI: 10.1007/s11103-016-0522-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 08/02/2016] [Indexed: 05/21/2023]
Abstract
The photoreceptor UV RESISTANCE LOCUS 8 (UVR8) specifically mediates photomorphogenic responses to UV-B wavelengths. UVR8 acts by regulating transcription of a set of genes, but the underlying mechanisms are unknown. Previous research indicated that UVR8 can associate with chromatin, but the specificity and functional significance of this interaction are not clear. Here we show, by chromatin immunoprecipitation, that UV-B exposure of Arabidopsis increases acetylation of lysines K9 and/or K14 of histone H3 at UVR8-regulated gene loci in a UVR8-dependent manner. The transcription factors HY5 and/or HYH, which mediate UVR8-regulated transcription, are also required for this chromatin modification, at least for the ELIP1 gene. Furthermore, sequencing of the immunoprecipitated DNA revealed that all UV-B-induced enrichments in H3K9,14diacetylation across the genome are UVR8-dependent, and approximately 40 % of the enriched loci contain known UVR8-regulated genes. In addition, inhibition of histone acetylation by anacardic acid reduces the UV-B induced, UVR8 mediated expression of ELIP1 and CHS. No evidence was obtained in yeast 2-hybrid assays for a direct interaction between either UVR8 or HY5 and several proteins involved in light-regulated histone modification, nor for the involvement of these proteins in UVR8-mediated responses in plants, although functional redundancy between proteins could influence the results. In summary, this study shows that UVR8 regulates a specific chromatin modification associated with transcriptional regulation of a set of UVR8-target genes.
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Affiliation(s)
- Christos N Velanis
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bower Building, Glasgow, G12 8QQ, UK
| | - Pawel Herzyk
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bower Building, Glasgow, G12 8QQ, UK
- Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, University of Glasgow, Garscube Estate, Switchback Road, Bearsden, G61 1QH, UK
| | - Gareth I Jenkins
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bower Building, Glasgow, G12 8QQ, UK.
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Fransz P, Linc G, Lee C, Aflitos SA, Lasky JR, Toomajian C, Ali H, Peters J, van Dam P, Ji X, Kuzak M, Gerats T, Schubert I, Schneeberger K, Colot V, Martienssen R, Koornneef M, Nordborg M, Juenger TE, de Jong H, Schranz ME. Molecular, genetic and evolutionary analysis of a paracentric inversion in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 88:159-178. [PMID: 27436134 PMCID: PMC5113708 DOI: 10.1111/tpj.13262] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 06/29/2016] [Accepted: 07/01/2016] [Indexed: 05/02/2023]
Abstract
Chromosomal inversions can provide windows onto the cytogenetic, molecular, evolutionary and demographic histories of a species. Here we investigate a paracentric 1.17-Mb inversion on chromosome 4 of Arabidopsis thaliana with nucleotide precision of its borders. The inversion is created by Vandal transposon activity, splitting an F-box and relocating a pericentric heterochromatin segment in juxtaposition with euchromatin without affecting the epigenetic landscape. Examination of the RegMap panel and the 1001 Arabidopsis genomes revealed more than 170 inversion accessions in Europe and North America. The SNP patterns revealed historical recombinations from which we infer diverse haplotype patterns, ancient introgression events and phylogenetic relationships. We find a robust association between the inversion and fecundity under drought. We also find linkage disequilibrium between the inverted region and the early flowering Col-FRIGIDA allele. Finally, SNP analysis elucidates the origin of the inversion to South-Eastern Europe approximately 5000 years ago and the FRI-Col allele to North-West Europe, and reveals the spreading of a single haplotype to North America during the 17th to 19th century. The 'American haplotype' was identified from several European localities, potentially due to return migration.
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Affiliation(s)
- Paul Fransz
- Department of Plant Development and (Epi)GeneticsSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdamthe Netherlands
| | - Gabriella Linc
- Department of Plant Development and (Epi)GeneticsSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdamthe Netherlands
- Present address: Centre for Agricultural ResearchHungarian Academy of SciencesAgricultural InstituteMartonvásárHungary
| | - Cheng‐Ruei Lee
- Gregor Mendel Institute (GMI)Austrian Academy of SciencesVienna Biocenter (VBC)Dr Bohr‐Gasse 3Vienna1030Austria
| | | | - Jesse R. Lasky
- Department of BiologyPennsylvania State UniversityUniversity ParkPAUSA
| | | | - Hoda Ali
- Department of Cytogenetics and Genome AnalysisThe Leibniz Institute of Plant Genetics and Crop Plant Research (IPK)GaterslebenGermany
- Present address: Department of Genetics and CytologyNational Research CenterCairoEgypt
| | - Janny Peters
- Section Plant GeneticsInstitute for Wetland and Water Research Faculty of ScienceRadboud UniversityNijmegenthe Netherlands
| | - Peter van Dam
- Section Plant GeneticsInstitute for Wetland and Water Research Faculty of ScienceRadboud UniversityNijmegenthe Netherlands
- Present address: Department of Molecular Plant PathologyUniversity of AmsterdamAmsterdamThe Netherlands
| | - Xianwen Ji
- Laboratory of GeneticsWageningen UniversityWageningenthe Netherlands
| | - Mateusz Kuzak
- MAD, Dutch Genomics Service & Support ProviderSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdamthe Netherlands
- Present address: Netherlands eScience CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Tom Gerats
- Section Plant GeneticsInstitute for Wetland and Water Research Faculty of ScienceRadboud UniversityNijmegenthe Netherlands
| | - Ingo Schubert
- Department of Cytogenetics and Genome AnalysisThe Leibniz Institute of Plant Genetics and Crop Plant Research (IPK)GaterslebenGermany
| | | | - Vincent Colot
- Unité de Recherche en Génomique Végétale (URGV)INRA/CNRS/UEVE 2 Rue Gaston CrémieuxEvry Cedex91057France
- Present address: Institut de Biologie de l'Ecole Normale Supérieure (IBENS)ParisFrance
| | - Rob Martienssen
- Cold Spring Harbor LaboratoryCold Spring HarborNew YorkNY11724USA
| | - Maarten Koornneef
- Laboratory of GeneticsWageningen UniversityWageningenthe Netherlands
- Max Planck Institute for Plant Breeding ResearchKöln50829Germany
| | - Magnus Nordborg
- Gregor Mendel Institute (GMI)Austrian Academy of SciencesVienna Biocenter (VBC)Dr Bohr‐Gasse 3Vienna1030Austria
| | | | - Hans de Jong
- Laboratory of GeneticsWageningen UniversityWageningenthe Netherlands
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