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Wang Z, Xia A, Wang Q, Cui Z, Lu M, Ye Y, Wang Y, He Y. Natural polymorphisms in ZMET2 encoding a DNA methyltransferase modulate the number of husk layers in maize. PLANT PHYSIOLOGY 2024; 195:2129-2142. [PMID: 38431291 PMCID: PMC11213254 DOI: 10.1093/plphys/kiae113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 01/30/2024] [Accepted: 02/08/2024] [Indexed: 03/05/2024]
Abstract
DNA methylation affects agronomic traits and the environmental adaptability of crops, but the natural polymorphisms in DNA methylation-related genes and their contributions to phenotypic variation in maize (Zea mays) remain elusive. Here, we show that a polymorphic 10-bp insertion/deletion variant in the 3'UTR of Zea methyltransferase2 (ZMET2) alters its transcript level and accounts for variation in the number of maize husk layers. ZMET2 encodes a chromomethylase and is required for maintaining genome-wide DNA methylation in the CHG sequence context. Disruption of ZMET2 increased the number of husk layers and resulted in thousands of differentially methylated regions, a proportion of which were also distinguishable in natural ZMET2 alleles. Population genetic analyses indicated that ZMET2 was a target of selection and might play a role in the spread of maize from tropical to temperate regions. Our results provide important insights into the natural variation of ZMET2 that confers both global and locus-specific effects on DNA methylation, which contribute to phenotypic diversity in maize.
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Affiliation(s)
- Zi Wang
- State Key Laboratory of Maize Bio-breeding, National Maize Improvement Center of China, China Agricultural University, Beijing 100094, China
| | - Aiai Xia
- State Key Laboratory of Maize Bio-breeding, National Maize Improvement Center of China, China Agricultural University, Beijing 100094, China
| | - Qi Wang
- State Key Laboratory of Maize Bio-breeding, National Maize Improvement Center of China, China Agricultural University, Beijing 100094, China
| | - Zhenhai Cui
- Shenyang Key Laboratory of Maize Genomic Selection Breeding, Shenyang Agricultural University, Shenyang 110866, China
| | - Ming Lu
- Maize Research Institute, Jilin Academy of Agricultural Sciences, Gongzhuling 136100, China
| | - Yusheng Ye
- Maize Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang 110065, China
| | - Yanbo Wang
- Maize Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang 110065, China
| | - Yan He
- State Key Laboratory of Maize Bio-breeding, National Maize Improvement Center of China, China Agricultural University, Beijing 100094, China
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2
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Abugammie B, Wang R, Hu Y, Pang J, Luan Y, Liu B, Jiang L, Lv R. Spontaneous chromosome instability and tissue culture-induced karyotypic alteration in wheat-Thinopyrum intermedium alien addition lines. PLANTA 2024; 260:17. [PMID: 38834908 DOI: 10.1007/s00425-024-04450-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2024] [Accepted: 05/28/2024] [Indexed: 06/06/2024]
Abstract
MAIN CONCLUSION Wheat lines harboring wild-relative chromosomes can be karyotypically unstable during long-term maintenance. Tissue culture exacerbates chromosomal instability but appears inefficient to induce somatic homoeologous exchange between alien and wheat chromosomes. We assessed if long-term refrigerator storage with regular renewal via self-fertilization, a widely used practice for crop germplasm maintenance, would ensure genetic fidelity of alien addition lines, and explored the possibility of inducing somatic homoeologues exchange by tissue culture. We cytogenetically characterized sampled stock seeds of originally confirmed 12 distinct wheat-Thinopyrum intermedium alien addition lines (dubbed TAI lines), and subjected immature embryos of the TAI lines to tissue culture. We find eight of the 12 TAI lines were karyotypically departed from their original identity as bona fide disomic alien addition lines due to extensive loss of whole-chromosomes of both Th. intermedium and wheat origins during the ca. 3-decade storage. Rampant numerical chromosome variations (NCVs) involving both alien and wheat chromosomes were detected in regenerated plants of all 12 studied TAI lines, but at variable rates among the wheat sub-genomes and chromosomes. Compared with NCVs, structural chromosome variations (SCVs) occurred at substantially lower rates, and no SCV involving the added alien chromosomes was observed. The NCVs manifested only moderate effects on phenotypes of the regenerated plants under field conditions.
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Affiliation(s)
- Bahaa Abugammie
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
- Department of Genetics, Faculty of Agriculture, Minia University, Minia, Egypt
| | - Ruisi Wang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Yue Hu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Jinsong Pang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Yushi Luan
- School of Bioengineering, Dalian University of Technology, Dalian, 116024, China
| | - Bao Liu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Lily Jiang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China.
| | - Ruili Lv
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China.
- School of Bioengineering, Dalian University of Technology, Dalian, 116024, China.
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3
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Boissinot J, Adamek K, Jones AMP, Normandeau E, Boyle B, Torkamaneh D. Comparative restriction enzyme analysis of methylation (CREAM) reveals methylome variability within a clonal in vitro cannabis population. FRONTIERS IN PLANT SCIENCE 2024; 15:1381154. [PMID: 38872884 PMCID: PMC11169872 DOI: 10.3389/fpls.2024.1381154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 05/14/2024] [Indexed: 06/15/2024]
Abstract
The primary focus of medicinal cannabis research is to ensure the stability of cannabis lines for consistent administration of chemically uniform products to patients. In recent years, tissue culture has emerged as a valuable technique for genetic preservation and rapid multiplication of cannabis clones. However, there is concern that the physical and chemical conditions of the growing media can induce somaclonal variation, potentially impacting the viability and uniformity of clones. To address this concern, we developed Comparative Restriction Enzyme Analysis of Methylation (CREAM), a novel method to assess DNA methylation patterns and used it to study a population of 78 cannabis clones maintained in tissue culture. Through bioinformatics analysis of the methylome, we successfully detected 2,272 polymorphic methylated regions among the clones. Remarkably, our results demonstrated that DNA methylation patterns were preserved across subcultures within the clonal population, allowing us to distinguish between two subsets of clonal lines used in this study. These findings significantly contribute to our understanding of the epigenetic variability within clonal lines in medicinal cannabis produced through tissue culture techniques. This knowledge is crucial for understanding the effects of tissue culture on DNA methylation and ensuring the consistency and reliability of medicinal cannabis products with therapeutic properties. Additionally, the CREAM method is a fast and affordable technology to get a first glimpse at methylation in a biological system. It offers a valuable tool for studying epigenetic variation in other plant species, thereby facilitating broader applications in plant biotechnology and crop improvement.
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Affiliation(s)
- Justin Boissinot
- Département de phytologie, Université Laval, Québec, QC, Canada
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
- Centre de recherche et d’innovation sur les végétaux (CRIV), Université Laval, Québec, QC, Canada
- Institut intelligence et données (IID), Université Laval, Québec, QC, Canada
| | - Kristian Adamek
- Department of Plant Agriculture, University of Guelph, Guelph, ON, Canada
| | | | - Eric Normandeau
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
| | - Brian Boyle
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
| | - Davoud Torkamaneh
- Département de phytologie, Université Laval, Québec, QC, Canada
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
- Centre de recherche et d’innovation sur les végétaux (CRIV), Université Laval, Québec, QC, Canada
- Institut intelligence et données (IID), Université Laval, Québec, QC, Canada
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4
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Lee S, Park YS, Rhee JH, Chu H, Frost JM, Choi Y. Insights into plant regeneration: cellular pathways and DNA methylation dynamics. PLANT CELL REPORTS 2024; 43:120. [PMID: 38634973 PMCID: PMC11026228 DOI: 10.1007/s00299-024-03216-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Accepted: 04/08/2024] [Indexed: 04/19/2024]
Abstract
Plants, known for their immobility, employ various mechanisms against stress and damage. A prominent feature is the formation of callus tissue-a cellular growth phenomenon that remains insufficiently explored, despite its distinctive cellular plasticity compared to vertebrates. Callus formation involves dedifferentiated cells, with a subset attaining pluripotency. Calluses exhibit an extraordinary capacity to reinitiate cellular division and undergo structural transformations, generating de novo shoots and roots, thereby developing into regenerated plants-a testament to the heightened developmental plasticity inherent in plants. In this way, plant regeneration through clonal propagation is a widely employed technique for vegetative reproduction. Thus, exploration of the biological components involved in regaining pluripotency contributes to the foundation upon which methods of somatic plant propagation can be advanced. This review provides an overview of the cellular pathway involved in callus and subsequent de novo shoot formation from already differentiated plant tissue, highlighting key genes critical to this process. In addition, it explores the intricate realm of epigenetic regulatory processes, emphasizing the nuanced dynamics of DNA methylation that contribute to plant regeneration. Finally, we briefly discuss somaclonal variation, examining its relation to DNA methylation, and investigating the heritability of epigenomic changes in crops.
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Affiliation(s)
- Seunga Lee
- Department of Biological Sciences, Seoul National University, Seoul, Korea
- Research Center for Plant Plasticity, Seoul National University, Seoul, Korea
| | - Young Seo Park
- Department of Biological Sciences, Seoul National University, Seoul, Korea
| | - Ji Hoon Rhee
- Department of Biological Sciences, Seoul National University, Seoul, Korea
- Research Center for Plant Plasticity, Seoul National University, Seoul, Korea
| | - Hyojeong Chu
- Department of Biological Sciences, Seoul National University, Seoul, Korea
- Research Center for Plant Plasticity, Seoul National University, Seoul, Korea
- The Research Institute of Basic Sciences, Seoul National University, Seoul, Korea
| | - Jennifer M Frost
- Genomics and Child Health, The Blizard Institute, Queen Mary University of London, London, UK
| | - Yeonhee Choi
- Department of Biological Sciences, Seoul National University, Seoul, Korea.
- Research Center for Plant Plasticity, Seoul National University, Seoul, Korea.
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5
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D'Amico-Willman KM, Niederhuth CE, Sovic MG, Anderson ES, Gradziel TM, Fresnedo-Ramírez J. Hypermethylation and small RNA expression are associated with increased age in almond (Prunus dulcis [Mill.] D.A. Webb) accessions. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2024; 338:111918. [PMID: 37956826 DOI: 10.1016/j.plantsci.2023.111918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 10/20/2023] [Accepted: 11/04/2023] [Indexed: 11/15/2023]
Abstract
The focus of this study is to profile changes in DNA methylation and small RNA expression occurring with increased age in almond breeding germplasm to identify possible biomarkers of age that can be used to assess the potential of individuals to develop aging-related disorders. To profile DNA methylation in almond germplasm, 70 methylomes were generated from almond individuals representing three age cohorts (11, 7, and 2 years old) using an enzymatic methyl-seq approach followed by analysis to call differentially methylated regions (DMRs) within these cohorts. Small RNA (sRNA) expression was profiled in three breeding selections, each from two age cohorts (1 and 6 years old), using sRNA-Seq followed by differential expression analysis. Weighted chromosome-level methylation analysis reveals hypermethylation in 11-year-old almond breeding selections when compared to 2-year-old selections in the CG and CHH contexts. Seventeen consensus DMRs were identified in all age contrasts. sRNA expression differed significantly between the two age cohorts tested, with significantly decreased expression in sRNAs in the 6-year-old selections compared to the 1-year-old. Almond shows a pattern of hypermethylation and decreased sRNA expression with increased age. Identified DMRs and differentially expressed sRNAs could function as putative biomarkers of age following validation in additional age groups.
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Affiliation(s)
| | - Chad E Niederhuth
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Michael G Sovic
- Center for Applied Plant Sciences, The Ohio State University, Columbus, OH 43210, USA
| | - Elizabeth S Anderson
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA
| | - Thomas M Gradziel
- Department of Plant Sciences, University of California, Davis, CA 95616, USA
| | - Jonathan Fresnedo-Ramírez
- Translational Plant Sciences, The Ohio State University, Columbus, OH 43210, USA; Center for Applied Plant Sciences, The Ohio State University, Columbus, OH 43210, USA; Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA.
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6
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Türkoğlu A, Haliloğlu K, Demirel F, Aydin M, Çiçek S, Yiğider E, Demirel S, Piekutowska M, Szulc P, Niedbała G. Machine Learning Analysis of the Impact of Silver Nitrate and Silver Nanoparticles on Wheat ( Triticum aestivum L.): Callus Induction, Plant Regeneration, and DNA Methylation. PLANTS (BASEL, SWITZERLAND) 2023; 12:4151. [PMID: 38140479 PMCID: PMC10747064 DOI: 10.3390/plants12244151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 12/24/2023]
Abstract
The objective of this study was to comprehend the efficiency of wheat regeneration, callus induction, and DNA methylation through the application of mathematical frameworks and artificial intelligence (AI)-based models. This research aimed to explore the impact of treatments with AgNO3 and Ag-NPs on various parameters. The study specifically concentrated on analyzing RAPD profiles and modeling regeneration parameters. The treatments and molecular findings served as input variables in the modeling process. It included the use of AgNO3 and Ag-NPs at different concentrations (0, 2, 4, 6, and 8 mg L-1). The in vitro and epigenetic characteristics were analyzed using several machine learning (ML) methods, including support vector machine (SVM), random forest (RF), extreme gradient boosting (XGBoost), k-nearest neighbor classifier (KNN), and Gaussian processes classifier (GP) methods. This study's results revealed that the highest values for callus induction (CI%) and embryogenic callus induction (EC%) occurred at a concentration of 2 mg L-1 of Ag-NPs. Additionally, the regeneration efficiency (RE) parameter reached its peak at a concentration of 8 mg L-1 of AgNO3. Taking an epigenetic approach, AgNO3 at a concentration of 2 mg L-1 demonstrated the highest levels of genomic template stability (GTS), at 79.3%. There was a positive correlation seen between increased levels of AgNO3 and DNA hypermethylation. Conversely, elevated levels of Ag-NPs were associated with DNA hypomethylation. The models were used to estimate the relationships between the input elements, including treatments, concentration, GTS rates, and Msp I and Hpa II polymorphism, and the in vitro output parameters. The findings suggested that the XGBoost model exhibited superior performance scores for callus induction (CI), as evidenced by an R2 score of 51.5%, which explained the variances. Additionally, the RF model explained 71.9% of the total variance and showed superior efficacy in terms of EC%. Furthermore, the GP model, which provided the most robust statistics for RE, yielded an R2 value of 52.5%, signifying its ability to account for a substantial portion of the total variance present in the data. This study exemplifies the application of various machine learning models in the cultivation of mature wheat embryos under the influence of treatments and concentrations involving AgNO3 and Ag-NPs.
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Affiliation(s)
- Aras Türkoğlu
- Department of Field Crops, Faculty of Agriculture, Necmettin Erbakan University, Konya 42310, Türkiye
| | - Kamil Haliloğlu
- Department of Field Crops, Faculty of Agriculture, Ataturk University, Erzurum 25240, Türkiye;
| | - Fatih Demirel
- Department of Agricultural Biotechnology, Faculty of Agriculture, Igdır University, Igdir 76000, Türkiye;
| | - Murat Aydin
- Department of Agricultural Biotechnology, Faculty of Agriculture, Ataturk University, Erzurum 25240, Türkiye; (M.A.); (S.Ç.); (E.Y.)
| | - Semra Çiçek
- Department of Agricultural Biotechnology, Faculty of Agriculture, Ataturk University, Erzurum 25240, Türkiye; (M.A.); (S.Ç.); (E.Y.)
| | - Esma Yiğider
- Department of Agricultural Biotechnology, Faculty of Agriculture, Ataturk University, Erzurum 25240, Türkiye; (M.A.); (S.Ç.); (E.Y.)
| | - Serap Demirel
- Department of Molecular Biology and Genetics, Faculty of Science, Van Yüzüncü Yıl University, Van 65080, Türkiye;
| | - Magdalena Piekutowska
- Department of Geoecology and Geoinformation, Institute of Biology and Earth Sciences, Pomeranian University in Słupsk, 27 Partyzantów St., 76-200 Słupsk, Poland;
| | - Piotr Szulc
- Department of Agronomy, Poznań University of Life Sciences, Dojazd 11, 60-632 Poznań, Poland;
| | - Gniewko Niedbała
- Department of Biosystems Engineering, Faculty of Environmental and Mechanical Engineering, Poznań University of Life Sciences, Wojska Polskiego 50, 60-627 Poznań, Poland
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7
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Eren B, Türkoğlu A, Haliloğlu K, Demirel F, Nowosad K, Özkan G, Niedbała G, Pour-Aboughadareh A, Bujak H, Bocianowski J. Investigation of the Influence of Polyamines on Mature Embryo Culture and DNA Methylation of Wheat ( Triticum aestivum L.) Using the Machine Learning Algorithm Method. PLANTS (BASEL, SWITZERLAND) 2023; 12:3261. [PMID: 37765424 PMCID: PMC10536335 DOI: 10.3390/plants12183261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 08/21/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023]
Abstract
Numerous factors can impact the efficiency of callus formation and in vitro regeneration in wheat cultures through the introduction of exogenous polyamines (PAs). The present study aimed to investigate in vitro plant regeneration and DNA methylation patterns utilizing the inter-primer binding site (iPBS) retrotransposon and coupled restriction enzyme digestion-iPBS (CRED-iPBS) methods in wheat. This investigation involved the application of distinct types of PAs (Put: putrescine, Spd: spermidine, and Spm: spermine) at varying concentrations (0, 0.5, 1, and 1.5 mM). The subsequent outcomes were subjected to predictive modeling using diverse machine learning (ML) algorithms. Based on the specific polyamine type and concentration utilized, the results indicated that 1 mM Put and Spd were the most favorable PAs for supporting endosperm-associated mature embryos. Employing an epigenetic approach, Put at concentrations of 0.5 and 1.5 mM exhibited the highest levels of genomic template stability (GTS) (73.9%). Elevated Spd levels correlated with DNA hypermethylation while reduced Spm levels were linked to DNA hypomethylation. The in vitro and epigenetic characteristics were predicted using ML techniques such as the support vector machine (SVM), extreme gradient boosting (XGBoost), and random forest (RF) models. These models were employed to establish relationships between input variables (PAs, concentration, GTS rates, Msp I polymorphism, and Hpa II polymorphism) and output parameters (in vitro measurements). This comparative analysis aimed to evaluate the performance of the models and interpret the generated data. The outcomes demonstrated that the XGBoost method exhibited the highest performance scores for callus induction (CI%), regeneration efficiency (RE), and the number of plantlets (NP), with R2 scores explaining 38.3%, 73.8%, and 85.3% of the variances, respectively. Additionally, the RF algorithm explained 41.5% of the total variance and showcased superior efficacy in terms of embryogenic callus induction (ECI%). Furthermore, the SVM model, which provided the most robust statistics for responding embryogenic calluses (RECs%), yielded an R2 value of 84.1%, signifying its ability to account for a substantial portion of the total variance present in the data. In summary, this study exemplifies the application of diverse ML models to the cultivation of mature wheat embryos in the presence of various exogenous PAs and concentrations. Additionally, it explores the impact of polymorphic variations in the CRED-iPBS profile and DNA methylation on epigenetic changes, thereby contributing to a comprehensive understanding of these regulatory mechanisms.
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Affiliation(s)
- Barış Eren
- Department of Agricultural Biotechnology, Faculty of Agriculture, Igdır University, Igdir 76000, Türkiye; (B.E.); (F.D.)
| | - Aras Türkoğlu
- Department of Field Crops, Faculty of Agriculture, Necmettin Erbakan University, Konya 42310, Türkiye
| | - Kamil Haliloğlu
- Department of Field Crops, Faculty of Agriculture, Ataturk University, Erzurum 25240, Türkiye;
| | - Fatih Demirel
- Department of Agricultural Biotechnology, Faculty of Agriculture, Igdır University, Igdir 76000, Türkiye; (B.E.); (F.D.)
| | - Kamila Nowosad
- Department of Genetics, Plant Breeding and Seed Production, Wrocław University of Environmental and Life Sciences, Grunwaldzki 24A, 53-363 Wrocław, Poland;
| | - Güller Özkan
- Department of Biology, Faculty of Science, Ankara University, Ankara 06100, Türkiye;
| | - Gniewko Niedbała
- Department of Biosystems Engineering, Faculty of Environmental and Mechanical Engineering, Poznan University of Life Sciences, Wojska Polskiego 50, 60-627 Poznań, Poland;
| | - Alireza Pour-Aboughadareh
- Seed and Plant Improvement Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj P.O. Box 3158854119, Iran;
| | - Henryk Bujak
- Department of Genetics, Plant Breeding and Seed Production, Wrocław University of Environmental and Life Sciences, Grunwaldzki 24A, 53-363 Wrocław, Poland;
- Research Centre for Cultivar Testing (COBORU), Słupia Wielka 34, 63-022 Słupia Wielka, Poland
| | - Jan Bocianowski
- Department of Mathematical and Statistical Methods, Poznan University of Life Sciences, Wojska Polskiego 28, 60-637 Poznań, Poland
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Song B, Ning W, Wei D, Jiang M, Zhu K, Wang X, Edwards D, Odeny DA, Cheng S. Plant genome resequencing and population genomics: Current status and future prospects. MOLECULAR PLANT 2023; 16:1252-1268. [PMID: 37501370 DOI: 10.1016/j.molp.2023.07.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 05/30/2023] [Accepted: 07/25/2023] [Indexed: 07/29/2023]
Abstract
Advances in DNA sequencing technology have sparked a genomics revolution, driving breakthroughs in plant genetics and crop breeding. Recently, the focus has shifted from cataloging genetic diversity in plants to exploring their functional significance and delivering beneficial alleles for crop improvement. This transformation has been facilitated by the increasing adoption of whole-genome resequencing. In this review, we summarize the current progress of population-based genome resequencing studies and how these studies affect crop breeding. A total of 187 land plants from 163 countries have been resequenced, comprising 54 413 accessions. As part of resequencing efforts 367 traits have been surveyed and 86 genome-wide association studies have been conducted. Economically important crops, particularly cereals, vegetables, and legumes, have dominated the resequencing efforts, leaving a gap in 49 orders, including Lycopodiales, Liliales, Acorales, Austrobaileyales, and Commelinales. The resequenced germplasm is distributed across diverse geographic locations, providing a global perspective on plant genomics. We highlight genes that have been selected during domestication, or associated with agronomic traits, and form a repository of candidate genes for future research and application. Despite the opportunities for cross-species comparative genomics, many population genomic datasets are not accessible, impeding secondary analyses. We call for a more open and collaborative approach to population genomics that promotes data sharing and encourages contribution-based credit policy. The number of plant genome resequencing studies will continue to rise with the decreasing DNA sequencing costs, coupled with advances in analysis and computational technologies. This expansion, in terms of both scale and quality, holds promise for deeper insights into plant trait genetics and breeding design.
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Affiliation(s)
- Bo Song
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
| | - Weidong Ning
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China; Huazhong Agricultural University, College of Informatics, Hubei Key Laboratory of Agricultural Bioinformatics, Wuhan, Hubei, China
| | - Di Wei
- Biotechnology Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 53007, China
| | - Mengyun Jiang
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China; State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng 475004, China; Shenzhen Research Institute of Henan University, Shenzhen 518000, China
| | - Kun Zhu
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China; State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng 475004, China; Shenzhen Research Institute of Henan University, Shenzhen 518000, China
| | - Xingwei Wang
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China; State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng 475004, China; Shenzhen Research Institute of Henan University, Shenzhen 518000, China
| | - David Edwards
- School of Biological Sciences and Institute of Agriculture, University of Western Australia, Perth, WA, Australia
| | - Damaris A Odeny
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) - Eastern and Southern Africa, Nairobi, Kenya
| | - Shifeng Cheng
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China.
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9
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Ooi SE, Sarpan N, Taranenko E, Feshah I, Nuraziyan A, Roowi SH, Burhan MN, Jayanthi N, Rahmah ARS, Teh OK, Ong-Abdullah M, Tatarinova TV. Small RNAs and Karma methylation in Elaeis guineensis mother palms are linked to high clonal mantling. PLANT MOLECULAR BIOLOGY 2023; 111:345-363. [PMID: 36609897 DOI: 10.1007/s11103-022-01330-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Accepted: 12/08/2022] [Indexed: 06/17/2023]
Abstract
The mantled phenotype is an abnormal somaclonal variant arising from the oil palm cloning process and severe phenotypes lead to oil yield losses. Hypomethylation of the Karma retrotransposon within the B-type MADS-box EgDEF1 gene has been associated with this phenotype. While abnormal Karma-EgDEF1 hypomethylation was detected in mantled clones, we examined the methylation state of Karma in ortets that gave rise to high mantling rates in their clones. Small RNAs (sRNAs) were proposed to play a role in Karma hypomethylation as part of the RNA-directed DNA methylation process, hence differential expression analysis of sRNAs between the ortet groups was conducted. While no sRNA was differentially expressed at the Karma-EgDEF1 region, three sRNA clusters were differentially regulated in high-mantling ortets. The first two down-regulated clusters were possibly derived from long non-coding RNAs while the third up-regulated cluster was derived from the intron of a DnaJ chaperone gene. Several predicted mRNA targets for the first two sRNA clusters conversely displayed increased expression in high-mantling relative to low-mantling ortets. These predicted mRNA targets may be associated with defense or pathogenesis response. In addition, several differentially methylated regions (DMRs) were identified in Karma and its surrounding regions, mainly comprising subtle CHH hypomethylation in high-mantling ortets. Four of the 12 DMRs were located in a region corresponding to hypomethylated areas at the 3'end of Karma previously reported in mantled clones. Further investigations on these sRNAs and DMRs may indicate the predisposition of certain ortets towards mantled somaclonal variation.
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Affiliation(s)
- Siew-Eng Ooi
- Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia.
| | - Norashikin Sarpan
- 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
- Laboratory of Forest Genomics, Genome Research and Education Center, Institute of Fundamental Biology and Biotechnology, Siberian Federal University, Krasnoyarsk, Russia, 660036
| | - Ishak Feshah
- Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | - Azimi Nuraziyan
- Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | | | | | - Nagappan Jayanthi
- Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | - Abdul Rahman Siti Rahmah
- Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | - Ooi-Kock Teh
- Institute of Plant and Microbial Biology, Academia Sinica, 128 Sec. 2, Academia Rd., Nankang, Taipei, Taiwan, R.O.C
| | - Meilina Ong-Abdullah
- 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.
- Laboratory of Forest Genomics, Genome Research and Education Center, Institute of Fundamental Biology and Biotechnology, Siberian Federal University, Krasnoyarsk, Russia, 660036.
- Vavilov Institute for General Genetics, Moscow, Russia.
- A.A. Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russia.
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10
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Ibañez VN, Quadrana L. Shaping inheritance: how distinct reproductive strategies influence DNA methylation memory in plants. Curr Opin Genet Dev 2023; 78:102018. [PMID: 36525825 DOI: 10.1016/j.gde.2022.102018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 11/04/2022] [Accepted: 11/22/2022] [Indexed: 12/15/2022]
Abstract
DNA methylation is a major epigenetic mark involved in the silencing of genes and transposable elements (TEs). DNA methylation varies significantly across the plant life cycle, but is efficiently reinforced during reproduction, ensuring stable silencing of TEs. Plants are remarkably flexible in their mode of reproduction and numerous species, including crops, can propagate asexually, skipping one or more of these critical reinforcement steps. In this review, we summarize recent advances in the characterization of DNA methylation inheritance in sexual and asexual plants. We argue that because most epigenetic reinforcement appears to occur during seed formation, methylomes of asexual seeds should resemble that of their sexual counterparts. Conversely, clonally propagated plants are expected to be hypomethylated and undergo frequent stochastic epigenetic changes. Last, we provide insights on how the use of nonmodel organisms will advance our understanding of epigenetic inheritance in plants.
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Affiliation(s)
- Verónica Noé Ibañez
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, Université Paris Diderot, 91190 Gif sur Yvette, France. https://twitter.com/veronik_noe
| | - Leandro Quadrana
- Institute of Plant Sciences Paris-Saclay (IPS2), Université Paris-Saclay, CNRS, INRAE, Université Evry, Université Paris Diderot, 91190 Gif sur Yvette, France.
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11
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Tuncel A, Qi Y. CRISPR/Cas mediated genome editing in potato: Past achievements and future directions. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 325:111474. [PMID: 36174801 DOI: 10.1016/j.plantsci.2022.111474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 08/29/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
Genome engineering has been re-shaping plant biotechnology and agriculture. Crop improvement using the recently developed gene editing techniques is now easier, faster, and more precise than ever. Although considered to be a global food security crop, potato has not benefitted enough from diverse collection of these techniques. Unique genetic features of cultivated potatoes such as tetrasomic inheritance, high genomic heterozygosity, and inbreeding depression hamper conventional breeding of this important crop. Therefore, genome editing provides an excellent arsenal of tools for trait improvement in potato. Moreover, using specific transformation protocols, it is possible to engineer transgene free commercial varieties. In this review we first describe the past achievements in potato genome editing and highlight some of the missing aspects of these efforts. Then, we discuss about technical challenges of genome editing in potato and present approaches to overcome these difficulties. Finally, we talk about genome editing applications that have not been explored in potato and point out some of the missing venues in literature.
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Affiliation(s)
- Aytug Tuncel
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, USA.
| | - Yiping Qi
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, USA; Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD, USA.
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12
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Wibowo AT, Antunez-Sanchez J, Dawson A, Price J, Meehan C, Wrightsman T, Collenberg M, Bezrukov I, Becker C, Benhamed M, Weigel D, Gutierrez-Marcos J. Predictable and stable epimutations induced during clonal plant propagation with embryonic transcription factor. PLoS Genet 2022; 18:e1010479. [PMID: 36383565 PMCID: PMC9731469 DOI: 10.1371/journal.pgen.1010479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 12/08/2022] [Accepted: 10/15/2022] [Indexed: 11/17/2022] Open
Abstract
Clonal propagation is frequently used in commercial plant breeding and biotechnology programs because it minimizes genetic variation, yet it is not uncommon to observe clonal plants with stable phenotypic changes, a phenomenon known as somaclonal variation. Several studies have linked epigenetic modifications induced during regeneration with this newly acquired phenotypic variation. However, the factors that determine the extent of somaclonal variation and the molecular changes underpinning this process remain poorly understood. To address this gap in our knowledge, we compared clonally propagated Arabidopsis thaliana plants derived from somatic embryogenesis using two different embryonic transcription factors- RWP-RK DOMAIN-CONTAINING 4 (RKD4) or LEAFY COTYLEDON2 (LEC2) and from two epigenetically distinct founder tissues. We found that both the epi(genetic) status of the explant and the regeneration protocol employed play critical roles in shaping the molecular and phenotypic landscape of clonal plants. Phenotypic variation in regenerated plants can be largely explained by the inheritance of tissue-specific DNA methylation imprints, which are associated with specific transcriptional and metabolic changes in sexual progeny of clonal plants. For instance, regenerants were particularly affected by the inheritance of root-specific epigenetic imprints, which were associated with an increased accumulation of salicylic acid in leaves and accelerated plant senescence. Collectively, our data reveal specific pathways underpinning the phenotypic and molecular variation that arise and accumulate in clonal plant populations.
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Affiliation(s)
- Anjar Tri Wibowo
- School of Life Science, University of Warwick, Coventry, United Kingdom
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tubingen, Germany
- Department of Biology, Faculty of Science and Technology, Airlangga University, Surabaya City, East Java, Indonesia
| | | | - Alexander Dawson
- School of Life Science, University of Warwick, Coventry, United Kingdom
| | - Jonathan Price
- School of Life Science, University of Warwick, Coventry, United Kingdom
| | - Cathal Meehan
- School of Life Science, University of Warwick, Coventry, United Kingdom
| | - Travis Wrightsman
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tubingen, Germany
| | - Maximillian Collenberg
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tubingen, Germany
| | - Ilja Bezrukov
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tubingen, Germany
| | - Claude Becker
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tubingen, Germany
- Ludwig-Maximilians-University of Munich, Faculty of Biology, Biocenter, Martinsried, Germany
| | - Moussa Benhamed
- Université Paris-Saclay, Centre National de la Recherche Scientifique, Institut National De La Recherche Agronomique, University of Évry, Institute of Plant Sciences Paris-Saclay (IPS2), Orsay, France
| | - Detlef Weigel
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tubingen, Germany
- * E-mail: (DW); (JGM)
| | - Jose Gutierrez-Marcos
- School of Life Science, University of Warwick, Coventry, United Kingdom
- * E-mail: (DW); (JGM)
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13
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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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14
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Wijerathna-Yapa A, Ramtekey V, Ranawaka B, Basnet BR. Applications of In Vitro Tissue Culture Technologies in Breeding and Genetic Improvement of Wheat. PLANTS (BASEL, SWITZERLAND) 2022; 11:2273. [PMID: 36079653 PMCID: PMC9459818 DOI: 10.3390/plants11172273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/13/2022] [Accepted: 08/29/2022] [Indexed: 12/20/2022]
Abstract
Sources of new genetic variability have been limited to existing germplasm in the past. Wheat has been studied extensively for various agronomic traits located throughout the genome. The large size of the chromosomes and the ability of its polyploid genome to tolerate the addition or loss of chromosomes facilitated rapid progress in the early study of wheat genetics using cytogenetic techniques. At the same time, its large genome size has limited the progress in genetic characterization studies focused on diploid species, with a small genome and genetic engineering procedures already developed. Today, the genetic transformation and gene editing procedures offer attractive alternatives to conventional techniques for breeding wheat because they allow one or more of the genes to be introduced or altered into an elite cultivar without affecting its genetic background. Recently, significant advances have been made in regenerating various plant tissues, providing the essential basis for regenerating transgenic plants. In addition, Agrobacterium-mediated, biolistic, and in planta particle bombardment (iPB) gene delivery procedures have been developed for wheat transformation and advanced transgenic wheat development. As a result, several useful genes are now available that have been transferred or would be helpful to be transferred to wheat in addition to the current traditional effort to improve trait values, such as resistance to abiotic and biotic factors, grain quality, and plant architecture. Furthermore, the in planta genome editing method will significantly contribute to the social implementation of genome-edited crops to innovate the breeding pipeline and leverage unique climate adaptations.
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Affiliation(s)
- Akila Wijerathna-Yapa
- ARC Centre of Excellence for Plant Success in Nature and Agriculture, St Lucia, QLD 4072, Australia
- School of Biological Sciences, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Vinita Ramtekey
- ICAR-Indian Institute of Seed Science, Kushmaur, Mau, Uttar Pradesh 275103, India
| | - Buddhini Ranawaka
- ARC Centre of Excellence for Plant Success in Nature and Agriculture, St Lucia, QLD 4072, Australia
- Centre for Agriculture and the Bioeconomy, Institute for Future Environments, Queensland University of Technology (QUT), 2 George Street, Brisbane, QLD 4000, Australia
| | - Bhoja Raj Basnet
- Global Wheat Program, International Maize and Wheat Improvement Center (CIMMYT), El Batán 56237, Mexico
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15
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Read A, Weiss T, Crisp PA, Liang Z, Noshay J, Menard CC, Wang C, Song M, Hirsch CN, Springer NM, Zhang F. Genome-wide loss of CHH methylation with limited transcriptome changes in Setaria viridis DOMAINS REARRANGED METHYLTRANSFERASE (DRM) mutants. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 111:103-116. [PMID: 35436373 PMCID: PMC9541237 DOI: 10.1111/tpj.15781] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 04/12/2022] [Indexed: 05/17/2023]
Abstract
The DOMAINS REARRANGED METHYLTRANSFERASEs (DRMs) are crucial for RNA-directed DNA methylation (RdDM) in plant species. Setaria viridis is a model monocot species with a relatively compact genome that has limited transposable element (TE) content. CRISPR-based genome editing approaches were used to create loss-of-function alleles for the two putative functional DRM genes in S. viridis to probe the role of RdDM. Double mutant (drm1ab) plants exhibit some morphological abnormalities but are fully viable. Whole-genome methylation profiling provided evidence for the widespread loss of methylation in CHH sequence contexts, particularly in regions with high CHH methylation in wild-type plants. Evidence was also found for the locus-specific loss of CG and CHG methylation, even in some regions that lack CHH methylation. Transcriptome profiling identified genes with altered expression in the drm1ab mutants. However, the majority of genes with high levels of CHH methylation directly surrounding the transcription start site or in nearby promoter regions in wild-type plants do not have altered expression in the drm1ab mutant, even when this methylation is lost, suggesting limited regulation of gene expression by RdDM. Detailed analysis of the expression of TEs identified several transposons that are transcriptionally activated in drm1ab mutants. These transposons are likely to require active RdDM for the maintenance of transcriptional repression.
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Affiliation(s)
- Andrew Read
- Department of Plant and Microbial BiologyUniversity of MinnesotaSaint PaulMinnesota55108USA
| | - Trevor Weiss
- Department of Plant and Microbial BiologyUniversity of MinnesotaSaint PaulMinnesota55108USA
- Center for Precision Plant GenomicsUniversity of MinnesotaSaint PaulMinnesota55108USA
| | - Peter A. Crisp
- Department of Plant and Microbial BiologyUniversity of MinnesotaSaint PaulMinnesota55108USA
- School of Agriculture and Food SciencesThe University of QueenslandBrisbaneQueensland4072Australia
| | - Zhikai Liang
- Department of Plant and Microbial BiologyUniversity of MinnesotaSaint PaulMinnesota55108USA
| | - Jaclyn Noshay
- Department of Plant and Microbial BiologyUniversity of MinnesotaSaint PaulMinnesota55108USA
| | - Claire C. Menard
- Department of Agronomy and Plant GeneticsUniversity of MinnesotaSaint PaulMinnesota55108USA
| | - Chunfang Wang
- Department of Plant and Microbial BiologyUniversity of MinnesotaSaint PaulMinnesota55108USA
- Center for Precision Plant GenomicsUniversity of MinnesotaSaint PaulMinnesota55108USA
| | - Meredith Song
- Department of Genetics, Cell Biology and DevelopmentUniversity of MinnesotaMinneapolisMinnesota55108USA
| | - Candice N. Hirsch
- Department of Agronomy and Plant GeneticsUniversity of MinnesotaSaint PaulMinnesota55108USA
| | - Nathan M. Springer
- Department of Plant and Microbial BiologyUniversity of MinnesotaSaint PaulMinnesota55108USA
- Center for Precision Plant GenomicsUniversity of MinnesotaSaint PaulMinnesota55108USA
| | - Feng Zhang
- Department of Plant and Microbial BiologyUniversity of MinnesotaSaint PaulMinnesota55108USA
- Center for Precision Plant GenomicsUniversity of MinnesotaSaint PaulMinnesota55108USA
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16
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Liu S, Wang X, Ding N, Liu Y, Li N, Ma Y, Zhao J, Wang Z, Li X, Fu X, Li L. Nucleotide Sequence Variation in Long-Term Tissue Cultures of Chinese Ginseng ( Panax ginseng C. A. Mey.). PLANTS (BASEL, SWITZERLAND) 2021; 11:79. [PMID: 35009083 PMCID: PMC8747682 DOI: 10.3390/plants11010079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/24/2021] [Accepted: 12/24/2021] [Indexed: 11/16/2022]
Abstract
Plants have the salient biological property of totipotency, i.e., the capacity to regenerate a whole plant from virtually any kind of fully differentiated somatic cells after a process of dedifferentiation. This property has been well-documented by successful plant regeneration from tissue cultures of diverse plant species. However, the accumulation of somaclonal variation, especially karyotype alteration, during the tissue culture process compromises cell totipotency. In this respect, Chinese ginseng (Panax ginseng C. A. Mey.) is an exception in that it shows little decline in cell totipotency accompanied by remarkable chromosomal stability even after prolonged tissue cultures. However, it remains unclear whether chromosomal level stability necessarily couples with molecular genetic stability at the nucleotide sequence level, given that the two types of stabilities are generated by largely distinct mechanisms. Here, we addressed this issue by genome-wide comparisons at the single-base resolution of long-term tissue culture-regenerated P. ginseng plants. We identified abundant single nucleotide polymorphisms (SNPs) that have accumulated in cultured ginseng callus and are retained in the process of plant regeneration. These SNPs did not occur at random but showed differences among chromosomes and biased regional aggregation along a given chromosome. In addition, our results demonstrate that, compared with the overall genes, genes related to processes of cell totipotency and chromosomal stability possess lower mutation rates at both coding and flanking regions. In addition, collectively, the mutated genes exhibited higher expression levels than non-mutated genes and are significantly enriched in fundamental biological processes, including cellular component organization, development, and reproduction. These attributes suggest that the precipitated molecular level genetic variations during the process of regeneration in P. ginseng are likely under selection to fortify normal development. As such, they likely did not undermine chromosomal stability and totipotency of the long-term ginseng cultures.
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Affiliation(s)
- Sitong Liu
- School of Life Sciences, Jilin University, Changchun 130012, China;
| | - Xinfeng Wang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China; (X.W.); (N.D.)
| | - Ning Ding
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China; (X.W.); (N.D.)
| | - Yutong Liu
- Key Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China; (Y.L.); (N.L.); (J.Z.); (X.L.)
| | - Ning Li
- Key Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China; (Y.L.); (N.L.); (J.Z.); (X.L.)
| | - Yiqiao Ma
- Jilin Academy of Vegetable and Flower Sciences, Changchun 130033, China;
| | - Jing Zhao
- Key Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China; (Y.L.); (N.L.); (J.Z.); (X.L.)
| | - Zhenhui Wang
- Department of Agronomy, Jilin Agricultural University, Changchun 130118, China;
| | - Xiaomeng Li
- Key Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China; (Y.L.); (N.L.); (J.Z.); (X.L.)
| | - Xueqi Fu
- School of Life Sciences, Jilin University, Changchun 130012, China;
| | - Linfeng Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China; (X.W.); (N.D.)
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17
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Hou Q, Wan X. Epigenome and Epitranscriptome: Potential Resources for Crop Improvement. Int J Mol Sci 2021; 22:12912. [PMID: 34884725 PMCID: PMC8658206 DOI: 10.3390/ijms222312912] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/24/2021] [Accepted: 11/28/2021] [Indexed: 12/26/2022] Open
Abstract
Crop breeding faces the challenge of increasing food demand, especially under climatic changes. Conventional breeding has relied on genetic diversity by combining alleles to obtain desired traits. In recent years, research on epigenetics and epitranscriptomics has shown that epigenetic and epitranscriptomic diversity provides additional sources for crop breeding and harnessing epigenetic and epitranscriptomic regulation through biotechnologies has great potential for crop improvement. Here, we review epigenome and epitranscriptome variations during plant development and in response to environmental stress as well as the available sources for epiallele formation. We also discuss the possible strategies for applying epialleles and epitranscriptome engineering in crop breeding.
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Affiliation(s)
- Quancan Hou
- Zhongzhi International Institute of Agricultural Biosciences, Shunde Graduate School, Research Center of Biology and Agriculture, University of Science and Technology Beijing (USTB), Beijing 100024, China
- Beijing Engineering Laboratory of Main Crop Bio-Tech Breeding, Beijing International Science and Technology Cooperation Base of Bio-Tech Breeding, Beijing Solidwill Sci-Tech Co., Ltd., Beijing 100192, China
| | - Xiangyuan Wan
- Zhongzhi International Institute of Agricultural Biosciences, Shunde Graduate School, Research Center of Biology and Agriculture, University of Science and Technology Beijing (USTB), Beijing 100024, China
- Beijing Engineering Laboratory of Main Crop Bio-Tech Breeding, Beijing International Science and Technology Cooperation Base of Bio-Tech Breeding, Beijing Solidwill Sci-Tech Co., Ltd., Beijing 100192, China
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18
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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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19
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Abstract
Plant intra-individual and inter-individual variation can be determined by the epigenome, a set of covalent modifications of DNA and chromatin that can alter genome structure and activity without changes to the genome sequence. The epigenome of plant cells is plastic, that is, it can change in response to internal or external cues, such as during development or due to environmental changes, to create a memory of such events. Ongoing advances in technologies to read and write epigenomic patterns with increasing resolution, scale and precision are enabling the extent of plant epigenome variation to be more extensively characterized and functionally interrogated. In this Review, we discuss epigenome dynamics and variation within plants during development and in response to environmental changes, including stress, as well as between plants. We review known or potential functions of such plasticity and emphasize the importance of investigating the causality of epigenomic changes. Finally, we discuss emerging technologies that may underpin future research into plant epigenome plasticity.
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Affiliation(s)
- James P B Lloyd
- Australian Research Council Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Ryan Lister
- Australian Research Council Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, Perth, Western Australia, Australia.
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20
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The Underlying Nature of Epigenetic Variation: Origin, Establishment, and Regulatory Function of Plant Epialleles. Int J Mol Sci 2021; 22:ijms22168618. [PMID: 34445323 PMCID: PMC8395315 DOI: 10.3390/ijms22168618] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/03/2021] [Accepted: 08/08/2021] [Indexed: 11/17/2022] Open
Abstract
In plants, the gene expression and associated phenotypes can be modulated by dynamic changes in DNA methylation, occasionally being fixed in certain genomic loci and inherited stably as epialleles. Epiallelic variations in a population can occur as methylation changes at an individual cytosine position, methylation changes within a stretch of genomic regions, and chromatin changes in certain loci. Here, we focus on methylated regions, since it is unclear whether variations at individual methylated cytosines can serve any regulatory function, and the evidence for heritable chromatin changes independent of genetic changes is limited. While DNA methylation is known to affect and regulate wide arrays of plant phenotypes, most epialleles in the form of methylated regions have not been assigned any biological function. Here, we review how epialleles can be established in plants, serve a regulatory function, and are involved in adaptive processes. Recent studies suggest that most epialleles occur as byproducts of genetic variations, mainly from structural variants and Transposable Element (TE) activation. Nevertheless, epialleles that occur spontaneously independent of any genetic variations have also been described across different plant species. Here, we discuss how epialleles that are dependent and independent of genetic architecture are stabilized in the plant genome and how methylation can regulate a transcription relative to its genomic location.
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Lin G, He C, Zheng J, Koo DH, Le H, Zheng H, Tamang TM, Lin J, Liu Y, Zhao M, Hao Y, McFraland F, Wang B, Qin Y, Tang H, McCarty DR, Wei H, Cho MJ, Park S, Kaeppler H, Kaeppler SM, Liu Y, Springer N, Schnable PS, Wang G, White FF, Liu S. Chromosome-level genome assembly of a regenerable maize inbred line A188. Genome Biol 2021; 22:175. [PMID: 34108023 PMCID: PMC8188678 DOI: 10.1186/s13059-021-02396-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Accepted: 05/28/2021] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND The maize inbred line A188 is an attractive model for elucidation of gene function and improvement due to its high embryogenic capacity and many contrasting traits to the first maize reference genome, B73, and other elite lines. The lack of a genome assembly of A188 limits its use as a model for functional studies. RESULTS Here, we present a chromosome-level genome assembly of A188 using long reads and optical maps. Comparison of A188 with B73 using both whole-genome alignments and read depths from sequencing reads identify approximately 1.1 Gb of syntenic sequences as well as extensive structural variation, including a 1.8-Mb duplication containing the Gametophyte factor1 locus for unilateral cross-incompatibility, and six inversions of 0.7 Mb or greater. Increased copy number of carotenoid cleavage dioxygenase 1 (ccd1) in A188 is associated with elevated expression during seed development. High ccd1 expression in seeds together with low expression of yellow endosperm 1 (y1) reduces carotenoid accumulation, accounting for the white seed phenotype of A188. Furthermore, transcriptome and epigenome analyses reveal enhanced expression of defense pathways and altered DNA methylation patterns of the embryonic callus. CONCLUSIONS The A188 genome assembly provides a high-resolution sequence for a complex genome species and a foundational resource for analyses of genome variation and gene function in maize. The genome, in comparison to B73, contains extensive intra-species structural variations and other genetic differences. Expression and network analyses identify discrete profiles for embryonic callus and other tissues.
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Affiliation(s)
- Guifang Lin
- Department of Plant Pathology, Kansas State University, 4024 Throckmorton Center, Manhattan, KS, 66506-5502, USA
| | - Cheng He
- Department of Plant Pathology, Kansas State University, 4024 Throckmorton Center, Manhattan, KS, 66506-5502, USA
| | - Jun Zheng
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Dal-Hoe Koo
- Department of Plant Pathology, Kansas State University, 4024 Throckmorton Center, Manhattan, KS, 66506-5502, USA
| | - Ha Le
- Department of Plant Pathology, Kansas State University, 4024 Throckmorton Center, Manhattan, KS, 66506-5502, USA
| | - Huakun Zheng
- Department of Plant Pathology, Kansas State University, 4024 Throckmorton Center, Manhattan, KS, 66506-5502, USA
| | - Tej Man Tamang
- Department of Horticulture and Natural Resources, Kansas State University, Manhattan, KS, 66506-5502, USA
| | - Jinguang Lin
- Department of Plant Pathology, Kansas State University, 4024 Throckmorton Center, Manhattan, KS, 66506-5502, USA
- Present Address, Corvallis, OR, 97330, USA
| | - Yan Liu
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Mingxia Zhao
- Department of Plant Pathology, Kansas State University, 4024 Throckmorton Center, Manhattan, KS, 66506-5502, USA
| | - Yangfan Hao
- Department of Plant Pathology, Kansas State University, 4024 Throckmorton Center, Manhattan, KS, 66506-5502, USA
| | - Frank McFraland
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Bo Wang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA
| | - Yang Qin
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Haibao Tang
- Center for Genomics and Biotechnology and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Donald R McCarty
- Department of Horticulture, University of Florida, Gainesville, FL, 32611-0680, USA
| | - Hairong Wei
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI, 49931, USA
| | - Myeong-Je Cho
- Innovative Genomics Institute, University of California-Berkeley, Sunnyvale, CA, 94704, USA
| | - Sunghun Park
- Department of Horticulture and Natural Resources, Kansas State University, Manhattan, KS, 66506-5502, USA
| | - Heidi Kaeppler
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Shawn M Kaeppler
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Yunjun Liu
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Nathan Springer
- Department of Plant Biology, University of Minnesota, Saint Paul, MN, 55108, USA
| | - Patrick S Schnable
- Department of Agronomy, Iowa State University, Ames, IA, 50011-3605, USA
| | - Guoying Wang
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Frank F White
- Department of Plant Pathology, University of Florida, Gainesville, FL, 32611-0680, USA
| | - Sanzhen Liu
- Department of Plant Pathology, Kansas State University, 4024 Throckmorton Center, Manhattan, KS, 66506-5502, USA.
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Noshay JM, Springer NM. Stories that can't be told by SNPs; DNA methylation variation in plant populations. CURRENT OPINION IN PLANT BIOLOGY 2021; 61:101989. [PMID: 33445144 DOI: 10.1016/j.pbi.2020.101989] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/18/2020] [Accepted: 12/11/2020] [Indexed: 05/23/2023]
Abstract
Epigenetic variation has been observed in many plant populations. This variation can influence qualitative and quantitative traits. A key question is whether there is novel information in the epigenome that is not captured by SNP-based genetic markers. The answer likely varies depending on the sources and stability of epigenetic variation as well as the type of population being studied. We consider the epigenetic variation in several plant systems and how this relates to potential for hidden information that could increase our understanding of phenotypic variation.
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Affiliation(s)
- Jaclyn M Noshay
- Department of Plant and Microbial Biology, University of Minnesota, Saint Paul, MN 55108, USA
| | - Nathan M Springer
- Department of Plant and Microbial Biology, University of Minnesota, Saint Paul, MN 55108, USA.
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Kim SJ, Park JS, Shin YH, Park YD. Identification and Validation of Genetic Variations in Transgenic Chinese Cabbage Plants ( Brassica rapa ssp. pekinensis) by Next-Generation Sequencing. Genes (Basel) 2021; 12:genes12050621. [PMID: 33922022 PMCID: PMC8143544 DOI: 10.3390/genes12050621] [Citation(s) in RCA: 3] [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: 04/01/2021] [Revised: 04/16/2021] [Accepted: 04/19/2021] [Indexed: 01/24/2023] Open
Abstract
Transgenic plants are usually produced through tissue culture, which is an essential step in Agrobacterium-mediated plant transformation. However, genomic variations, termed somaclonal variations, have been detected in transgenic plants cultured in vitro. The occurrence of these variations should be as low as possible to secure the stability of transgenic crops. Determining the cause and mechanism of somaclonal variations in tissue culture-derived plants will help reduce the rate of variation and promote the stable expression of genes in transgenic plants. In order to determine the genetic variability in transgenic Chinese cabbage plants, we performed whole-genome resequencing and compared the sequencing data with the ‘CT001’ reference genome. The variation candidates that were expected to consistently occur in the transgenic lines were selected and validated. The single nucleotide polymorphism (SNP) and insertion and deletion (InDel) candidates were identified using the resequencing data and validated by reverse transcription (RT)-PCR analysis. The deduced amino acid sequences were used to determine whether the variations caused changes in the resulting polypeptide, and the annotations of the mutated genes were analyzed to predict the possible effects of the SNPs on gene function. In conclusion, we selected and validated the genetic variations identified in transgenic Chinese cabbage plants. Their genomes were expected to be affected by the process of Agrobacterium-mediated transformation. The findings of our study will provide a genetic basis for transgenic plant research.
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Affiliation(s)
| | | | | | - Young-Doo Park
- Correspondence: ; Tel.: +82-10-3338-9344; Fax: +82-31-202-8395
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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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25
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Orłowska R. Barley somatic embryogenesis-an attempt to modify variation induced in tissue culture. ACTA ACUST UNITED AC 2021; 28:9. [PMID: 33726856 PMCID: PMC7962293 DOI: 10.1186/s40709-021-00138-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 02/19/2021] [Indexed: 11/25/2022]
Abstract
Background Somatic embryogenesis is a phenomenon carried out in an environment that generates abiotic stress. Thus, regenerants may differ from the source of explants at the morphological, genetic, and epigenetic levels. The DNA changes may be the outcome of induction media ingredients (i.e., copper and silver ions) and their concentrations and time of in vitro cultures. Results This study optimised the level of copper and silver ion concentration in culture media parallel with the induction medium longevity step towards obtaining barley regenerants via somatic embryogenesis with a minimum or maximum level of tissue culture-induced differences between the donor plant and its regenerants. The optimisation process is based on tissue culture-induced variation evaluated via the metAFLP approach for regenerants derived under varying in vitro tissue culture conditions and exploited by the Taguchi method. In the optimisation and verification experiments, various copper and silver ion concentrations and the different number of days differentiated the tested trials concerning the tissue culture-induced variation level, DNA demethylation, and de novo methylation, including symmetric (CG, CHG) and asymmetric (CHH) DNA sequence contexts. Verification of optimised conditions towards obtaining regenerants with minimum and maximum variability compared to donor plants proved useful. The main changes that discriminate optimised conditions belonged to DNA demethylation events with particular stress on CHG context. Conclusions The combination of tissue culture-induced variation evaluated for eight experimental trials and implementation of the Taguchi method allowed the optimisation of the in vitro tissue culture conditions towards the minimum and maximum differences between a source of tissue explants (donor plant) and its regenerants from somatic embryos. The tissue culture-induced variation characteristic is mostly affected by demethylation with preferences towards CHG sequence context.
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Affiliation(s)
- Renata Orłowska
- Plant Breeding & Acclimatization Institute-National Research Institute, 05-870 Błonie, Radzików, Poland.
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Zhang M, Ma X, Wang C, Li Q, Meyers BC, Springer NM, Walbot V. CHH DNA methylation increases at 24-PHAS loci depend on 24-nt phased small interfering RNAs in maize meiotic anthers. THE NEW PHYTOLOGIST 2021; 229:2984-2997. [PMID: 33135165 DOI: 10.1111/nph.17060] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/14/2020] [Indexed: 05/23/2023]
Abstract
Plant phased small interfering RNAs (phasiRNAs) contribute to robust male fertility; however, specific functions remain undefined. In maize (Zea mays), male sterile23 (ms23), necessary for both 24-nt phasiRNA precursor (24-PHAS) loci and Dicer-like5 (Dcl5) expression, and dcl5-1 mutants unable to slice PHAS transcripts lack nearly all 24-nt phasiRNAs. Based on sequence capture bisulfite-sequencing, we find that CHH DNA methylation of most 24-PHAS loci is increased in meiotic anthers of control plants but not in the ms23 and dcl5 mutants. Because dcl5-1 anthers express PHAS precursors, we conclude that the 24-nt phasiRNAs, rather than just activation of PHAS transcription, are required for targeting increased CHH methylation at these loci. Although PHAS precursors are processed into multiple 24-nt phasiRNA products, there is substantial differential product accumulation. Abundant 24-nt phasiRNA positions corresponded to high CHH methylation within individual loci, reinforcing the conclusion that 24-nt phasiRNAs contribute to increased CHH methylation in cis.
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Affiliation(s)
- Mei Zhang
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Fragrant Hill, Beijing, 100093, China
| | - Xuxu Ma
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Fragrant Hill, Beijing, 100093, China
| | - Chunyu Wang
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Fragrant Hill, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qing Li
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, 55108, USA
| | - Blake C Meyers
- Donald Danforth Plant Science Center, St Louis, MO, 63132, USA
- Division of Plant Sciences, University of Missouri-Columbia, 52 Agriculture Lab, Columbia, MO, 65211, USA
| | - Nathan M Springer
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, 55108, USA
| | - Virginia Walbot
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
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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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Time of In Vitro Anther Culture May Moderate Action of Copper and Silver Ions that Affect the Relationship between DNA Methylation Change and the Yield of Barley Green Regenerants. PLANTS 2020; 9:plants9091064. [PMID: 32825181 PMCID: PMC7570150 DOI: 10.3390/plants9091064] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 08/10/2020] [Accepted: 08/17/2020] [Indexed: 12/18/2022]
Abstract
Plant anther culture allows for the regeneration of uniform and homozygous double haploids. However, off-type regenerants may appear as a result of so-called tissue culture-induced variation (TCIV). In addition, the presence of Cu2+ and Ag+ ions in the culture medium might influence the number of green plants. The regenerants were obtained via anther cultures of barley under varying Cu2+ and Ag+ ion concentrations in the induction medium during distinct time conditions. DArTseqMet markers were evaluated based on regenerants and donor plants and delivering data on DNA demethylation (DM) and de novo methylation (DNM) and changes in methylation (Delta). The number of green regenerated plants per 100 anthers (GPs) was evaluated. The Cu2+ and Ag+ ion concentrations moderated relationships between Delta and the number of green plants conditional on time of tissue cultures. Depending on the ions, moderated moderation is valid within the different time of anther culture. When the highest concentration of copper is analyzed, plant regeneration is possible under short ‘Time’ (21 days) of anther culture wherein Delta is negative or under elongated Time when Delta is positive. Under 21 days of culture, the highest concentration of silver ions and when Delta is negative, some regenerants could be evaluated. However, under high Ag+ concentration when Time of culture is long and Delta positive, the highest number of green plants could be obtained.
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Abstract
Plants are subjected to extreme environmental conditions and must adapt rapidly. The phytohormone abscisic acid (ABA) accumulates during abiotic stress, signaling transcriptional changes that trigger physiological responses. Epigenetic modifications often facilitate transcription, particularly at genes exhibiting temporal, tissue-specific and environmentally-induced expression. In maize (Zea mays), MEDIATOR OF PARAMUTATION 1 (MOP1) is required for progression of an RNA-dependent epigenetic pathway that regulates transcriptional silencing of loci genomewide. MOP1 function has been previously correlated with genomic regions adjoining particular types of transposable elements and genic regions, suggesting that this regulatory pathway functions to maintain distinct transcriptional activities within genomic spaces, and that loss of MOP1 may modify the responsiveness of some loci to other regulatory pathways. As critical regulators of gene expression, MOP1 and ABA pathways each regulate specific genes. To determine whether loss of MOP1 impacts ABA-responsive gene expression in maize, mop1-1 and Mop1 homozygous seedlings were subjected to exogenous ABA and RNA-sequencing. A total of 3,242 differentially expressed genes (DEGs) were identified in four pairwise comparisons. Overall, ABA-induced changes in gene expression were enhanced in mop1-1 homozygous plants. The highest number of DEGs were identified in ABA-induced mop1-1 mutants, including many transcription factors; this suggests combinatorial regulatory scenarios including direct and indirect transcriptional responses to genetic disruption (mop1-1) and/or stimulus-induction of a hierarchical, cascading network of responsive genes. Additionally, a modest increase in CHH methylation at putative MOP1-RdDM loci in response to ABA was observed in some genotypes, suggesting that epigenetic variation might influence environmentally-induced transcriptional responses in maize.
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Yu J, Xu F, Wei Z, Zhang X, Chen T, Pu L. Epigenomic landscape and epigenetic regulation in maize. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2020; 133:1467-1489. [PMID: 31965233 DOI: 10.1007/s00122-020-03549-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 01/14/2020] [Indexed: 05/12/2023]
Abstract
Epigenetic regulation has been implicated in the control of multiple agronomic traits in maize. Here, we review current advances in our understanding of epigenetic regulation, which has great potential for improving agronomic traits and the environmental adaptability of crops. Epigenetic regulation plays vital role in the control of complex agronomic traits. Epigenetic variation could contribute to phenotypic diversity and can be used to improve the quality and productivity of crops. Maize (Zea mays L.), one of the most widely cultivated crops for human food, animal feed, and ethanol biofuel, is a model plant for genetic studies. Recent advances in high-throughput sequencing technology have made possible the study of epigenetic regulation in maize on a genome-wide scale. In this review, we discuss recent epigenetic studies in maize many achieved by Chinese research groups. These studies have explored the roles of DNA methylation, posttranslational modifications of histones, chromatin remodeling, and noncoding RNAs in the regulation of gene expression in plant development and environment response. We also provide our future prospects for manipulating epigenetic regulation to improve crops.
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Affiliation(s)
- Jia Yu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fan Xu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Ziwei Wei
- School of Life Sciences, Anhui Agricultural University, Hefei, China
| | - Xiangxiang Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Tao Chen
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Li Pu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China.
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Orłowska R, Bednarek PT. Precise evaluation of tissue culture-induced variation during optimisation of in vitro regeneration regime in barley. PLANT MOLECULAR BIOLOGY 2020; 103:33-50. [PMID: 32048207 PMCID: PMC7170832 DOI: 10.1007/s11103-020-00973-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 01/30/2020] [Indexed: 05/15/2023]
Abstract
KEY MESSAGE The Taguchi method and metAFLP analysis were used to optimise barley regenerants towards maximum and minimum levels of tissue culture-induced variation. The subtle effects of symmetric and asymmetric methylation changes in regenerants were identified. Plant tissue cultures (PTCs) provide researchers with unique materials that accelerate the development of new breeding cultivars and facilitate studies on off-type regenerants. The emerging variability of regenerants derived from PTCs may have both genetic and epigenetic origins, and may be desirable or degrade the value of regenerated plants. Thus, it is crucial to determine how the PTC variation level can be controlled. The easiest way to manipulate total tissue culture-induced variation (TTCIV) is to utilise appropriate stress factors and suitable medium components. This study describes the optimisation of in vitro tissue culture-induced variation in plant regenerants derived from barley anther culture, and maximizes and minimizes regenerant variation compared with the source explants. The approach relied on methylation amplified fragment length polymorphism (metAFLP)-derived TTCIV characteristics, which were evaluated in regenerants derived under distinct tissue culture conditions and analysed via Taguchi statistics. The factors that may trigger TTCIV included CuSO4, AgNO3 and the total time spent on the induction medium. The donor plants prepared for regeneration purposes had 5.75% and 2.01% polymorphic metAFLP loci with methylation and sequence changes, respectively. The level of TTCIV (as the sum of all metAFLP characteristics analyzed) identified in optimisation and verification experiments reached 7.51 and 10.46%, respectively. In the trial designed to produce a minimum number of differences between donor and regenerant plants, CuSO4 and AgNO3 were more crucial than time, which was not a significant factor. In the trial designed to produce a maximum number of differences between donor and regenerant plants, all factors had comparable impact on variation. The Taguchi method reduced the time required for experimental trials compared with a grid method and suggested that medium modifications were required to control regenerant variation. Finally, the effects of symmetric and asymmetric methylation changes on regenerants were identified using novel aspects of the metAFLP method developed for this analysis.
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Affiliation(s)
- Renata Orłowska
- Department of Plant Physiology and Biochemistry, Plant Breeding and Acclimatization Institute-National Research Institute, Błonie, 05-870, Radzików, Poland
| | - Piotr Tomasz Bednarek
- Department of Plant Physiology and Biochemistry, Plant Breeding and Acclimatization Institute-National Research Institute, Błonie, 05-870, Radzików, Poland.
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Fan X, Chen J, Wu Y, Teo C, Xu G, Fan X. Genetic and Global Epigenetic Modification, Which Determines the Phenotype of Transgenic Rice? Int J Mol Sci 2020; 21:E1819. [PMID: 32155767 PMCID: PMC7084647 DOI: 10.3390/ijms21051819] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Revised: 02/28/2020] [Accepted: 03/01/2020] [Indexed: 01/17/2023] Open
Abstract
Transgenic technologies have been applied to a wide range of biological research. However, information on the potential epigenetic effects of transgenic technology is still lacking. Here, we show that the transgenic process can simultaneously induce both genetic and epigenetic changes in rice. We analyzed genetic, epigenetic, and phenotypic changes in plants subjected to tissue culture regeneration, using transgenic lines expressing the same coding sequence from two different promoters in transgenic lines of two rice cultivars: Wuyunjing7 (WYJ7) and Nipponbare (NP). We determined the expression of OsNAR2.1 in two overexpression lines generated from the two cultivars, and in the RNA interference (RNAi) OsNAR2.1 line in NP. DNA methylation analyses were performed on wild-type cultivars (WYJ7 and NP), regenerated lines (CK, T0 plants), segregation-derived wild-type from pOsNAR2.1-OsNAR2.1 (SDWT), pOsNAR2.1-OsNAR2.1, pUbi-OsNAR2.1, and RNAi lines. Interestingly, we observed global methylation decreased in the T0 regenerated line of WYJ7 (CK-WJY7) and pOsNAR2.1-OsNAR2.1 lines but increased in pUbi-OsNAR2.1 and RNAi lines of NP. Furthermore, the methylation pattern in SDWT returned to the WYJ7 level after four generations. Phenotypic changes were detected in all the generated lines except for SDWT. Global methylation was found to decrease by 13% in pOsNAR2.1-OsNAR2.1 with an increase in plant height of 4.69% compared with WYJ7, and increased by 18% in pUbi-OsNAR2.1 with an increase of 17.36% in plant height compared with NP. This suggests an absence of a necessary link between global methylation and the phenotype of transgenic plants with OsNAR2.1 gene over-expression. However, epigenetic changes can influence phenotype during tissue culture, as seen in the massive methylation in CK-WYJ7, T0 regenerated lines, resulting in decreased plant height compared with the wild-type, in the absence of a transformed gene. We conclude that in the transgenic lines the phenotype is mainly determined by the nature and function of the transgene after four generations of transformation, while the global epigenetic modification is dependent on the genetic background. Our research suggests an innovative insight in explaining the reason behind the occurrence of transgenic plants with random and undesirable phenotypes.
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Affiliation(s)
- Xiaoru Fan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, China; (X.F.); (J.C.); (G.X.)
| | - Jingguang Chen
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, China; (X.F.); (J.C.); (G.X.)
- CAAS-IRRI Joint Laboratory for Genomics-Assisted Germplasm Enhancement, Agricultural Genomics Institute in Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518116, China
| | - Yufeng Wu
- Bioinformatics Center, Nanjing Agricultural University, Nanjing 210095, China;
| | - CheeHow Teo
- Centre of Research in Biotechnology for Agriculture (CEBAR), University of Malaya, 50603 Kuala Lumpur, Malaysia;
| | - Guohua Xu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, China; (X.F.); (J.C.); (G.X.)
| | - Xiaorong Fan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, China; (X.F.); (J.C.); (G.X.)
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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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Xu J, Chen G, Hermanson PJ, Xu Q, Sun C, Chen W, Kan Q, Li M, Crisp PA, Yan J, Li L, Springer NM, Li Q. Population-level analysis reveals the widespread occurrence and phenotypic consequence of DNA methylation variation not tagged by genetic variation in maize. Genome Biol 2019; 20:243. [PMID: 31744513 PMCID: PMC6862797 DOI: 10.1186/s13059-019-1859-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Accepted: 10/10/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND DNA methylation can provide a source of heritable information that is sometimes entirely uncoupled from genetic variation. However, the extent of this uncoupling and the roles of DNA methylation in shaping diversity of both gene expression and phenotypes are hotly debated. Here, we investigate the genetic basis and biological functions of DNA methylation at a population scale in maize. RESULTS We perform targeted DNA methylation profiling for a diverse panel of 263 maize inbred genotypes. All genotypes show similar levels of DNA methylation globally, highlighting the importance of DNA methylation in maize development. Nevertheless, we identify more than 16,000 differentially methylated regions (DMRs) that are distributed across the 10 maize chromosomes. Genome-wide association analysis with high-density genetic markers reveals that over 60% of the DMRs are not tagged by SNPs, suggesting the presence of unique information in DMRs. Strong associations between DMRs and the expression of many genes are identified in both the leaf and kernel tissues, pointing to the biological significance of methylation variation. Association analysis with 986 metabolic traits suggests that DNA methylation is associated with phenotypic variation of 156 traits. There are some traits that only show significant associations with DMRs and not with SNPs. CONCLUSIONS These results suggest that DNA methylation can provide unique information to explain phenotypic variation in maize.
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Affiliation(s)
- Jing Xu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070 China
| | - Guo Chen
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070 China
- Institute of Nuclear and Biological Technology, Xinjiang Academy of Agricultural Sciences, Urumqi, 830091 China
| | - Peter J. Hermanson
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN 55108 USA
| | - Qiang Xu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070 China
| | - Changshuo Sun
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070 China
| | - Wenqing Chen
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070 China
| | - Qiuxin Kan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070 China
| | - Minqi Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070 China
| | - Peter A. Crisp
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN 55108 USA
| | - Jianbing Yan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070 China
| | - Lin Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070 China
| | - Nathan M. Springer
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN 55108 USA
| | - Qing Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070 China
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Lin W, Xiao X, Zhang H, Li Y, Liu S, Sun W, Zhang X, Wu Q. Whole-Genome Bisulfite Sequencing Reveals a Role for DNA Methylation in Variants from Callus Culture of Pineapple ( Ananas comosus L.). Genes (Basel) 2019; 10:genes10110877. [PMID: 31683898 PMCID: PMC6895883 DOI: 10.3390/genes10110877] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 10/26/2019] [Accepted: 10/29/2019] [Indexed: 11/16/2022] Open
Abstract
DNA methylation changes can occur in some loci during callus culture, resulting in somaclonal variations (SVs). In the present study, we applied whole genome bisulfite sequencing to analyze context-specific DNA methylation changes in the pineapple genome between the cutting seedings and 5 SV plants. In general, SV plants exhibited methylation patterns analogous to those of cutting seedlings (CK). A total of 27.98% of the genomic cytosines of CK were methylcytosines, which was higher than that of 5 SV plants. Moreover, mCG and mCHG was hypermethylated, whereas mCHH was hypomethylated among the 5 SV plants genomic when compared with the CK. Most of the variation of DNA methylation was distributed in gene bodies, thus suggesting that phenotypic differences are probably perturbed by genes methylated from callus culture. In addition, the methylated genes were highly enriched for the Gene Ontology (GO) categories of binding and catalytic activity, cell part and organelle, cellular process, abiotic stimulus, and DNA modification. These results suggest that methylation mediates these pathways in the callus culture of pineapple. The results also suggested that the callus culture induced DNA methylation may result in the SV.
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Affiliation(s)
- Wenqiu Lin
- South Subtropical Crop Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang 524091, China.
- Laboratory of Tropical Fruit Biology, Ministry of Agriculture, Zhanjiang 524091, China.
| | - Xi'ou Xiao
- South Subtropical Crop Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang 524091, China.
- Laboratory of Tropical Fruit Biology, Ministry of Agriculture, Zhanjiang 524091, China.
| | - Hongna Zhang
- South Subtropical Crop Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang 524091, China.
- Laboratory of Tropical Fruit Biology, Ministry of Agriculture, Zhanjiang 524091, China.
| | - Yunhe Li
- South Subtropical Crop Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang 524091, China.
- Laboratory of Tropical Fruit Biology, Ministry of Agriculture, Zhanjiang 524091, China.
| | - Shenghui Liu
- South Subtropical Crop Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang 524091, China.
- Laboratory of Tropical Fruit Biology, Ministry of Agriculture, Zhanjiang 524091, China.
| | - Weisheng Sun
- South Subtropical Crop Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang 524091, China.
- Laboratory of Tropical Fruit Biology, Ministry of Agriculture, Zhanjiang 524091, China.
| | - Xiumei Zhang
- South Subtropical Crop Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang 524091, China.
- Laboratory of Tropical Fruit Biology, Ministry of Agriculture, Zhanjiang 524091, China.
| | - Qingsong Wu
- South Subtropical Crop Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang 524091, China.
- Laboratory of Tropical Fruit Biology, Ministry of Agriculture, Zhanjiang 524091, China.
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Ji L, Mathioni SM, Johnson S, Tucker D, Bewick AJ, Do Kim K, Daron J, Slotkin RK, Jackson SA, Parrott WA, Meyers BC, Schmitz RJ. Genome-Wide Reinforcement of DNA Methylation Occurs during Somatic Embryogenesis in Soybean. THE PLANT CELL 2019; 31:2315-2331. [PMID: 31439802 PMCID: PMC6790092 DOI: 10.1105/tpc.19.00255] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/29/2019] [Accepted: 08/19/2019] [Indexed: 05/06/2023]
Abstract
Somatic embryogenesis is an important tissue culture technique that sometimes leads to phenotypic variation via genetic and/or epigenetic changes. To understand the genomic and epigenomic impacts of somatic embryogenesis, we characterized soybean (Glycine max) epigenomes sampled from embryos at 10 different stages ranging from 6 weeks to 13 years of continuous culture. We identified genome-wide increases in DNA methylation from cultured samples, especially at CHH sites. The hypermethylation almost exclusively occurred in regions previously possessing non-CG methylation and was accompanied by increases in the expression of genes encoding the RNA-directed DNA methylation (RdDM) machinery. The epigenomic changes were similar between somatic and zygotic embryogenesis. Following the initial global wave of hypermethylation, rare decay events of maintenance methylation were observed, and the extent of the decay increased with time in culture. These losses in DNA methylation were accompanied by downregulation of genes encoding the RdDM machinery and transcriptome reprogramming reminiscent of transcriptomes during late-stage seed development. These results reveal a process for reinforcing already silenced regions to maintain genome integrity during somatic embryogenesis over the short term, which eventually decays at certain loci over longer time scales.
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Affiliation(s)
- Lexiang Ji
- Institute of Bioinformatics, University of Georgia, Athens, Georgia 30602
| | | | - Sarah Johnson
- Institute for Plant Breeding Genetics and Genomics, University of Georgia, Athens, Georgia 30602
| | - Donna Tucker
- Institute for Plant Breeding Genetics and Genomics, University of Georgia, Athens, Georgia 30602
| | - Adam J Bewick
- Department of Genetics, University of Georgia, Athens, Georgia 30602
| | - Kyung Do Kim
- Center for Applied Genetic Technologies, University of Georgia, Athens, Georgia 30602
| | - Josquin Daron
- Department of Molecular Genetics, Ohio State University, Columbus, Ohio 43210
| | - R Keith Slotkin
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
- Department of Molecular Genetics, Ohio State University, Columbus, Ohio 43210
| | - Scott A Jackson
- Center for Applied Genetic Technologies, University of Georgia, Athens, Georgia 30602
| | - Wayne A Parrott
- Institute for Plant Breeding Genetics and Genomics, University of Georgia, Athens, Georgia 30602
| | - Blake C Meyers
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
- Division of Plant Sciences, University of Missouri, Columbia, Missouri 63132
| | - Robert J Schmitz
- Department of Genetics, University of Georgia, Athens, Georgia 30602
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Pucker B, Rückert C, Stracke R, Viehöver P, Kalinowski J, Weisshaar B. Twenty-Five Years of Propagation in Suspension Cell Culture Results in Substantial Alterations of the Arabidopsis Thaliana Genome. Genes (Basel) 2019; 10:E671. [PMID: 31480756 PMCID: PMC6770967 DOI: 10.3390/genes10090671] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 08/23/2019] [Accepted: 08/29/2019] [Indexed: 01/16/2023] Open
Abstract
Arabidopsis thaliana is one of the best studied plant model organisms. Besides cultivation in greenhouses, cells of this plant can also be propagated in suspension cell culture. At7 is one such cell line that was established about 25 years ago. Here, we report the sequencing and the analysis of the At7 genome. Large scale duplications and deletions compared to the Columbia-0 (Col-0) reference sequence were detected. The number of deletions exceeds the number of insertions, thus indicating that a haploid genome size reduction is ongoing. Patterns of small sequence variants differ from the ones observed between A. thaliana accessions, e.g., the number of single nucleotide variants matches the number of insertions/deletions. RNA-Seq analysis reveals that disrupted alleles are less frequent in the transcriptome than the native ones.
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Affiliation(s)
- Boas Pucker
- Genetics and Genomics of Plants, Faculty of Biology, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, NRW, Germany.
| | - Christian Rückert
- Microbial Genomics and Biotechnology, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, NRW, Germany
| | - Ralf Stracke
- Genetics and Genomics of Plants, Faculty of Biology, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, NRW, Germany
| | - Prisca Viehöver
- Genetics and Genomics of Plants, Faculty of Biology, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, NRW, Germany
| | - Jörn Kalinowski
- Microbial Genomics and Biotechnology, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, NRW, Germany
| | - Bernd Weisshaar
- Genetics and Genomics of Plants, Faculty of Biology, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, NRW, Germany
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Fossi M, Amundson K, Kuppu S, Britt A, Comai L. Regeneration of Solanum tuberosum Plants from Protoplasts Induces Widespread Genome Instability. PLANT PHYSIOLOGY 2019; 180:78-86. [PMID: 30792232 PMCID: PMC6501065 DOI: 10.1104/pp.18.00906] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 02/07/2019] [Indexed: 05/18/2023]
Abstract
Nontransgenic genome editing in regenerable protoplasts, plant cells free of their cell wall, could revolutionize crop improvement because it reduces regulatory and technical complexity. However, plant tissue culture is known to engender frequent unwanted variation, termed somaclonal variation. To evaluate the contribution of large-scale genome instability to this phenomenon, we analyzed potatoes (Solanum tuberosum) regenerated from either protoplasts or stem explants for copy number changes by comparison of Illumina read depth. Whereas a control set of eight plants that had been propagated by cuttings displayed no changes, all 15 protoplast regenerants tested were affected by aneuploidy or structural chromosomal changes. Certain chromosomes displayed segmental deletions and duplications ranging from one to many. Resampling different leaves of the same plant found differences in three regenerants, indicating frequent persistence of instability. By comparison, 33 regenerants from stem explants used for Agrobacterium-mediated transformation displayed less frequent but still considerable (18%) large-scale copy number changes. Repetition of certain instability patterns suggested greater susceptibility in specific genomic sites. These results indicate that tissue culture, depending on the protocol used, can induce genomic instability resulting in large-scale changes likely to compromise final plant phenotype.
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Affiliation(s)
- Michelle Fossi
- Department of Plant Biology, University of California Davis, Davis, California 95616
- UC Davis Genome Center, University of California Davis, Davis, California 95616
| | - Kirk Amundson
- Department of Plant Biology, University of California Davis, Davis, California 95616
- UC Davis Genome Center, University of California Davis, Davis, California 95616
| | - Sundaram Kuppu
- Department of Plant Biology, University of California Davis, Davis, California 95616
| | - Anne Britt
- Department of Plant Biology, University of California Davis, Davis, California 95616
| | - Luca Comai
- Department of Plant Biology, University of California Davis, Davis, California 95616
- UC Davis Genome Center, University of California Davis, Davis, California 95616
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40
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Alonso C, Ramos‐Cruz D, Becker C. The role of plant epigenetics in biotic interactions. THE NEW PHYTOLOGIST 2019; 221:731-737. [PMID: 30156271 PMCID: PMC6726468 DOI: 10.1111/nph.15408] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 07/22/2018] [Indexed: 05/07/2023]
Abstract
Contents Summary 731 I. Biotic interactions in the context of genetic, epigenetic and environmental diversity 731 II. Biotic interactions affect epigenetic configuration 732 III. Plant epigenetic configuration influences biotic interactions 733 IV. Epigenetic memory in the context of biotic interactions 734 V. Conclusions and future research 735 Acknowledgements 735 Author contributions 735 References 735 SUMMARY: Plants are hubs of a wide range of biotic interactions with mutualist and antagonist animals, microbes and neighboring plants. Because the quality and intensity of those relationships can change over time, a fast and reversible response to stress is required. Here, we review recent studies on the role of epigenetic factors such as DNA methylation and histone modifications in modulating plant biotic interactions, and discuss the state of knowledge regarding their potential role in memory and priming. Moreover, we provide an overview of strategies to investigate the contribution of epigenetics to environmentally induced phenotypic changes in an ecological context, highlighting possible transitions from whole-genome high-resolution analyses in plant model organisms to informative reduced representation analyses in genomically less accessible species.
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Affiliation(s)
- Conchita Alonso
- Estación Biológica de DoñanaConsejo Superior de Investigaciones Científicas (CSIC)Av. Américo Vespucio 26Sevilla41092Spain
| | - Daniela Ramos‐Cruz
- Gregor Mendel Institute of Molecular Plant BiologyAustrian Academy of SciencesVienna Biocenter (VBC)Dr. Bohr Gasse 3Vienna1030Austria
| | - Claude Becker
- Gregor Mendel Institute of Molecular Plant BiologyAustrian Academy of SciencesVienna Biocenter (VBC)Dr. Bohr Gasse 3Vienna1030Austria
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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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