1
|
Korolenko A, Skinner MK. Generational stability of epigenetic transgenerational inheritance facilitates adaptation and evolution. Epigenetics 2024; 19:2380929. [PMID: 39104183 PMCID: PMC11305060 DOI: 10.1080/15592294.2024.2380929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 06/29/2024] [Accepted: 07/11/2024] [Indexed: 08/07/2024] Open
Abstract
The epigenome and epigenetic inheritance were not included in the original modern synthesis theory or more recent extended evolutionary synthesis of evolution. In a broad range of species, the environment has been shown to play a significant role in natural selection, which more recently has been shown to occur through epigenetic alterations and epigenetic inheritance. However, even with this evidence, the field of epigenetics and epigenetic inheritance has been left out of modern evolutionary synthesis, as well as other current evolutionary models. Epigenetic mechanisms can direct the regulation of genetic processes (e.g. gene expression) and also can be directly changed by the environment. In contrast, DNA sequence cannot be directly altered by the environment. The goal of this review is to present the evidence of how epigenetics and epigenetic inheritance can alter phenotypic variation in numerous species. This can occur at a significantly higher frequency than genetic change, so correlates with the frequency of evolutionary change. In addition, the concept and importance of generational stability of transgenerational inheritance is incorporated into evolutionary theory. For there to be a better understanding of evolutionary biology, we must incorporate all aspects of molecular (e.g. genetics and epigenetics) and biological sciences (e.g. environment and adaptation).
Collapse
Affiliation(s)
- Alexandra Korolenko
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA, USA
| | - Michael K. Skinner
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA, USA
| |
Collapse
|
2
|
Zhan W, Cui L, Yang S, Zhang K, Zhang Y, Yang J. Natural variations of heterosis-related allele-specific expression genes in promoter regions lead to allele-specific expression in maize. BMC Genomics 2024; 25:476. [PMID: 38745122 PMCID: PMC11092226 DOI: 10.1186/s12864-024-10395-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Accepted: 05/08/2024] [Indexed: 05/16/2024] Open
Abstract
BACKGROUND Heterosis has successfully enhanced maize productivity and quality. Although significant progress has been made in delineating the genetic basis of heterosis, the molecular mechanisms underlying its genetic components remain less explored. Allele-specific expression (ASE), the imbalanced expression between two parental alleles in hybrids, is increasingly being recognized as a factor contributing to heterosis. ASE is a complex process regulated by both epigenetic and genetic variations in response to developmental and environmental conditions. RESULTS In this study, we explored the differential characteristics of ASE by analyzing the transcriptome data of two maize hybrids and their parents under four light conditions. On the basis of allele expression patterns in different hybrids under various conditions, ASE genes were divided into three categories: bias-consistent genes involved in basal metabolic processes in a functionally complementary manner, bias-reversal genes adapting to the light environment, and bias-specific genes maintaining cell homeostasis. We observed that 758 ASE genes (ASEGs) were significantly overlapped with heterosis quantitative trait loci (QTLs), and high-frequency variations in the promoter regions of heterosis-related ASEGs were identified between parents. In addition, 10 heterosis-related ASEGs participating in yield heterosis were selected during domestication. CONCLUSIONS The comprehensive analysis of ASEGs offers a distinctive perspective on how light quality influences gene expression patterns and gene-environment interactions, with implications for the identification of heterosis-related ASEGs to enhance maize yield.
Collapse
Affiliation(s)
- Weimin Zhan
- College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
- Guangdong Provincial Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou, 510006, China
| | - Lianhua Cui
- College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
| | - Shuling Yang
- College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
| | - Kangni Zhang
- College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
| | - Yanpei Zhang
- College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Jianping Yang
- College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China.
| |
Collapse
|
3
|
Kakoulidou I, Johannes F. DNA methylation remodeling in F1 hybrids. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:671-681. [PMID: 36752648 DOI: 10.1111/tpj.16137] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/20/2023] [Accepted: 02/05/2023] [Indexed: 06/18/2023]
Abstract
F1 hybrids derived from a cross between two inbred parental lines often display widespread changes in DNA methylation patterns relative to their parents. To which extent these changes drive non-additive gene expression levels and phenotypic heterosis in F1 individuals is not fully resolved. Current mechanistic models propose that DNA methylation remodeling in hybrids is the result of epigenetic interactions between parental alleles via small interfering RNA (sRNA). These models have strong empirical support but are limited to genomic regions where the two parental lines differ in DNA methylation status. However, most remodeling events occur in parental regions with similar methylation patterns, and seem to be strongly conditioned by distally acting factors, even in isogenic hybrid systems. The molecular basis of these distal interactions is currently unknown, and will likely emerge as an active area of research in the future. Despite these gaps in our molecular understanding, parental DNA methylation states are statistically associated with heterosis, independent of genetic information, and may serve as biomarkers in crop breeding.
Collapse
Affiliation(s)
- Ioanna Kakoulidou
- Plant Epigenomics, Technical University of Munich, Emil-Ramman-Str. 4, 85354, Freising, Germany
| | - Frank Johannes
- Plant Epigenomics, Technical University of Munich, Emil-Ramman-Str. 4, 85354, Freising, Germany
| |
Collapse
|
4
|
Kumar S, Singh A, Bist CMS, Sharma M. Advancements in genetic techniques and functional genomics for enhancing crop traits and agricultural sustainability. Brief Funct Genomics 2024:elae017. [PMID: 38679487 DOI: 10.1093/bfgp/elae017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 04/03/2024] [Accepted: 04/16/2024] [Indexed: 05/01/2024] Open
Abstract
Genetic variability is essential for the development of new crop varieties with economically beneficial traits. The traits can be inherited from wild relatives or induced through mutagenesis. Novel genetic elements can then be identified and new gene functions can be predicted. In this study, forward and reverse genetics approaches were described, in addition to their applications in modern crop improvement programs and functional genomics. By using heritable phenotypes and linked genetic markers, forward genetics searches for genes by using traditional genetic mapping and allele frequency estimation. Despite recent advances in sequencing technology, omics and computation, genetic redundancy remains a major challenge in forward genetics. By analyzing close-related genes, we will be able to dissect their functional redundancy and predict possible traits and gene activity patterns. In addition to these predictions, sophisticated reverse gene editing tools can be used to verify them, including TILLING, targeted insertional mutagenesis, gene silencing, gene targeting and genome editing. By using gene knock-down, knock-up and knock-out strategies, these tools are able to detect genetic changes in cells. In addition, epigenome analysis and editing enable the development of novel traits in existing crop cultivars without affecting their genetic makeup by increasing epiallelic variants. Our understanding of gene functions and molecular dynamics of various biological phenomena has been revised by all of these findings. The study also identifies novel genetic targets in crop species to improve yields and stress tolerances through conventional and non-conventional methods. In this article, genetic techniques and functional genomics are specifically discussed and assessed for their potential in crop improvement.
Collapse
Affiliation(s)
- Surender Kumar
- Department of Biotechnology, College of Horticulture, Dr. Y. S. Parmar University of Horticulture and Forestry, Nauni, Solan-173230, Himachal Pradesh, India
| | - Anupama Singh
- Department of Biotechnology, College of Horticulture, Dr. Y. S. Parmar University of Horticulture and Forestry, Nauni, Solan-173230, Himachal Pradesh, India
| | - Chander Mohan Singh Bist
- Indian Council of Agricultural Research (ICAR)-Central Potato Research Institute, Shimla-171001, Himachal Pradesh, India
| | - Munish Sharma
- Department of Plant Sciences, Central University of Himachal Pradesh, Dharamshala-176215, Himachal Pradesh, India
| |
Collapse
|
5
|
Su J, Zhao L, Yang Y, Yang Y, Zhang X, Guan Z, Fang W, Chen F, Zhang F. Comparative transcriptome analysis provides molecular insights into heterosis of waterlogging tolerance in Chrysanthemum indicum. BMC PLANT BIOLOGY 2024; 24:259. [PMID: 38594635 PMCID: PMC11005212 DOI: 10.1186/s12870-024-04954-4] [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: 09/16/2023] [Accepted: 03/27/2024] [Indexed: 04/11/2024]
Abstract
BACKGROUND Heterosis breeding is one of the most important breeding methods for chrysanthemum. To date, the genetic mechanisms of heterosis for waterlogging tolerance in chrysanthemum are still unclear. This study aims to analyze the expression profiles and potential heterosis-related genes of two hybrid lines and their parents with extreme differences in waterlogging tolerance under control and waterlogging stress conditions by RNA-seq. RESULTS A population of 140 F1 progeny derived from Chrysanthemum indicum (Nanchang) (waterlogging-tolerant) and Chrysanthemum indicum (Nanjing) (waterlogging-sensitive) was used to characterize the extent of genetic variation in terms of seven waterlogging tolerance-related traits across two years. Lines 98 and 95, respectively displaying positive and negative overdominance heterosis for the waterlogging tolerance traits together with their parents under control and waterlogging stress conditions, were used for RNA-seq. In consequence, the maximal number of differentially expressed genes (DEGs) occurred in line 98. Gene ontology (GO) enrichment analysis revealed multiple stress-related biological processes for the common up-regulated genes. Line 98 had a significant increase in non-additive genes under waterlogging stress, with transgressive up-regulation and paternal-expression dominant patterns being the major gene expression profiles. Further, GO analysis identified 55 and 95 transgressive up-regulation genes that overlapped with the up-regulated genes shared by two parents in terms of responses to stress and stimulus, respectively. 6,640 genes in total displaying maternal-expression dominance patterns were observed in line 95. In addition, 16 key candidate genes, including SAP12, DOX1, and ERF017 which might be of significant importance for the formation of waterlogging tolerance heterosis in line 98, were highlighted. CONCLUSION The current study provides a comprehensive overview of the root transcriptomes among F1 hybrids and their parents under waterlogging stress. These findings lay the foundation for further studies on molecular mechanisms underlying chrysanthemum heterosis on waterlogging tolerance.
Collapse
Affiliation(s)
- Jiangshuo Su
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Biology of Ornamental Plants in East China, College of Horticulture, National Forestry and Grassland Administration, Nanjing Agricultural University, Weigang No.1, Nanjing, Jiangsu Province, 210095, P.R. China
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, 210014, China
| | - Limin Zhao
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Biology of Ornamental Plants in East China, College of Horticulture, National Forestry and Grassland Administration, Nanjing Agricultural University, Weigang No.1, Nanjing, Jiangsu Province, 210095, P.R. China
| | - Yingnan Yang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Biology of Ornamental Plants in East China, College of Horticulture, National Forestry and Grassland Administration, Nanjing Agricultural University, Weigang No.1, Nanjing, Jiangsu Province, 210095, P.R. China
| | - Yang Yang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Biology of Ornamental Plants in East China, College of Horticulture, National Forestry and Grassland Administration, Nanjing Agricultural University, Weigang No.1, Nanjing, Jiangsu Province, 210095, P.R. China
| | - Xuefeng Zhang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Biology of Ornamental Plants in East China, College of Horticulture, National Forestry and Grassland Administration, Nanjing Agricultural University, Weigang No.1, Nanjing, Jiangsu Province, 210095, P.R. China
| | - Zhiyong Guan
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Biology of Ornamental Plants in East China, College of Horticulture, National Forestry and Grassland Administration, Nanjing Agricultural University, Weigang No.1, Nanjing, Jiangsu Province, 210095, P.R. China
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, 210014, China
| | - Weimin Fang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Biology of Ornamental Plants in East China, College of Horticulture, National Forestry and Grassland Administration, Nanjing Agricultural University, Weigang No.1, Nanjing, Jiangsu Province, 210095, P.R. China
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, 210014, China
| | - Fadi Chen
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Biology of Ornamental Plants in East China, College of Horticulture, National Forestry and Grassland Administration, Nanjing Agricultural University, Weigang No.1, Nanjing, Jiangsu Province, 210095, P.R. China
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, 210014, China
| | - Fei Zhang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Biology of Ornamental Plants in East China, College of Horticulture, National Forestry and Grassland Administration, Nanjing Agricultural University, Weigang No.1, Nanjing, Jiangsu Province, 210095, P.R. China.
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, 210014, China.
| |
Collapse
|
6
|
Kakoulidou I, Piecyk RS, Meyer RC, Kuhlmann M, Gutjahr C, Altmann T, Johannes F. Mapping parental DMRs predictive of local and distal methylome remodeling in epigenetic F1 hybrids. Life Sci Alliance 2024; 7:e202402599. [PMID: 38290756 PMCID: PMC10828516 DOI: 10.26508/lsa.202402599] [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: 01/17/2024] [Revised: 01/21/2024] [Accepted: 01/22/2024] [Indexed: 02/01/2024] Open
Abstract
F1 hybrids derived from a cross between two inbred parental lines often display widespread changes in DNA methylation and gene expression patterns relative to their parents. An emerging challenge is to understand how parental epigenomic differences contribute to these events. Here, we generated a large mapping panel of F1 epigenetic hybrids, whose parents are isogenic but variable in their DNA methylation patterns. Using a combination of multi-omic profiling and epigenetic mapping strategies we show that differentially methylated regions in parental pericentromeres act as major reorganizers of hybrid methylomes and transcriptomes, even in the absence of genetic variation. These parental differentially methylated regions are associated with hybrid methylation remodeling events at thousands of target regions throughout the genome, both locally (in cis) and distally (in trans). Many of these distally-induced methylation changes lead to nonadditive expression of nearby genes and associate with phenotypic heterosis. Our study highlights the pleiotropic potential of parental pericentromeres in the functional remodeling of hybrid genomes and phenotypes.
Collapse
Affiliation(s)
- Ioanna Kakoulidou
- https://ror.org/02kkvpp62 Plant Epigenomics, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Munich, Germany
| | - Robert S Piecyk
- https://ror.org/02kkvpp62 Plant Epigenomics, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Munich, Germany
| | - Rhonda C Meyer
- https://ror.org/02skbsp27 Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Markus Kuhlmann
- https://ror.org/02skbsp27 Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Caroline Gutjahr
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Thomas Altmann
- https://ror.org/02skbsp27 Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Frank Johannes
- https://ror.org/02kkvpp62 Plant Epigenomics, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Munich, Germany
- https://ror.org/02kkvpp62 Institute of Advanced Studies, Technical University of Munich, Munich, Germany
| |
Collapse
|
7
|
Tennenbaum SR, Bortner R, Lynch C, Santymire R, Crosier A, Santiestevan J, Marinari P, Pukazhenthi BS, Comizzoli P, Hawkins MTR, Maldonado JE, Koepfli K, vonHoldt BM, DeCandia AL. Epigenetic changes to gene pathways linked to male fertility in ex situ black-footed ferrets. Evol Appl 2024; 17:e13634. [PMID: 38283602 PMCID: PMC10818088 DOI: 10.1111/eva.13634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 12/06/2023] [Accepted: 12/07/2023] [Indexed: 01/30/2024] Open
Abstract
Environmental variation can influence the reproductive success of species managed under human care and in the wild, yet the mechanisms underlying this phenomenon remain largely mysterious. Molecular mechanisms such as epigenetic modifiers are important in mediating the timing and progression of reproduction in humans and model organisms, but few studies have linked epigenetic variation to reproductive fitness in wildlife. Here, we investigated epigenetic variation in black-footed ferrets (Mustela nigripes), an endangered North American mammal reliant on ex situ management for survival and persistence in the wild. Despite similar levels of genetic diversity in human-managed and wild-born populations, individuals in ex situ facilities exhibit reproductive problems, such as poor sperm quality. Differences across these settings suggest that an environmentally driven decline in reproductive capacity may be occurring in this species. We examined the role of DNA methylation, one well-studied epigenetic modifier, in this emergent condition. We leveraged blood, testes, and semen samples from male black-footed ferrets bred in ex situ facilities and found tissue-type specificity in DNA methylation across the genome, although 1360 Gene Ontology terms associated with male average litter size shared functions across tissues. We then constructed gene networks of differentially methylated genomic sites associated with three different reproductive phenotypes to explore the putative biological impact of variation in DNA methylation. Sperm gene networks associated with average litter size and sperm count were functionally enriched for candidate genes involved in reproduction, development, and its regulation through transcriptional repression. We propose that DNA methylation plays an important role in regulating these reproductive phenotypes, thereby impacting the fertility of male ex situ individuals. Our results provide information into how DNA methylation may function in the alteration of reproductive pathways and phenotypes in artificial environments. These findings provide early insights to conservation hurdles faced in the protection of this rare species.
Collapse
Affiliation(s)
| | - Robyn Bortner
- U.S. Fish & Wildlife Service National Black‐Footed Ferret Conservation CenterCarrColoradoUSA
| | | | - Rachel Santymire
- Biology DepartmentGeorgia State UniversityAtlantaGeorgiaUSA
- Center for Species SurvivalSmithsonian's National Zoo and Conservation Biology InstituteFront RoyalVirginiaUSA
| | - Adrienne Crosier
- Center for Animal Care SciencesSmithsonian's National Zoo & Conservation Biology InstituteFront RoyalVirginiaUSA
| | - Jenny Santiestevan
- Center for Species SurvivalSmithsonian's National Zoo and Conservation Biology InstituteFront RoyalVirginiaUSA
| | - Paul Marinari
- Center for Animal Care SciencesSmithsonian's National Zoo & Conservation Biology InstituteFront RoyalVirginiaUSA
| | - Budhan S. Pukazhenthi
- Center for Species SurvivalSmithsonian's National Zoo and Conservation Biology InstituteFront RoyalVirginiaUSA
| | - Pierre Comizzoli
- Center for Species SurvivalSmithsonian's National Zoo and Conservation Biology InstituteFront RoyalVirginiaUSA
| | - Melissa T. R. Hawkins
- Division of Mammals, Department of Vertebrate ZoologyNational Museum of Natural HistoryWashingtonDCUSA
| | - Jesús E. Maldonado
- Center for Conservation GenomicsSmithsonian's National Zoo and Conservation Biology InstituteWashingtonDCUSA
| | - Klaus‐Peter Koepfli
- Center for Species SurvivalSmithsonian's National Zoo and Conservation Biology InstituteFront RoyalVirginiaUSA
- Smithsonian‐Mason School of ConservationGeorge Mason UniversityFront RoyalVirginiaUSA
| | | | - Alexandra L. DeCandia
- Center for Conservation GenomicsSmithsonian's National Zoo and Conservation Biology InstituteWashingtonDCUSA
- BiologyGeorgetown UniversityWashingtonDCUSA
| |
Collapse
|
8
|
Hamid R, Jacob F, Ghorbanzadeh Z, Jafari L, Alishah O. Dynamic roles of small RNAs and DNA methylation associated with heterosis in allotetraploid cotton (Gossypium hirsutum L.). BMC PLANT BIOLOGY 2023; 23:488. [PMID: 37828433 PMCID: PMC10571366 DOI: 10.1186/s12870-023-04495-2] [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: 05/17/2023] [Accepted: 09/28/2023] [Indexed: 10/14/2023]
Abstract
BACKGROUND Heterosis is a complex phenomenon wherein the hybrids outperform their parents. Understanding the underlying molecular mechanism by which hybridization leads to higher yields in allopolyploid cotton is critical for effective breeding programs. Here, we integrated DNA methylation, transcriptomes, and small RNA profiles to comprehend the genetic and molecular basis of heterosis in allopolyploid cotton at three developmental stages. RESULTS Transcriptome analysis revealed that numerous DEGs responsive to phytohormones (auxin and salicylic acid) were drastically altered in F1 hybrid compared to the parental lines. DEGs involved in energy metabolism and plant growth were upregulated, whereas DEGs related to basal defense were downregulated. Differences in homoeologous gene expression in F1 hybrid were greatly reduced after hybridization, suggesting that higher levels of parental expression have a vital role in heterosis. Small RNAome and methylome studies showed that the degree of DNA methylation in hybrid is higher when compared to the parents. A substantial number of allele-specific expression genes were found to be strongly regulated by CG allele-specific methylation levels. The hybrid exhibited higher 24-nt-small RNA (siRNA) expression levels than the parents. The regions in the genome with increased levels of 24-nt-siRNA were chiefly related to genes and their flanking regulatory regions, demonstrating a possible effect of these molecules on gene expression. The transposable elements correlated with siRNA clusters in the F1 hybrid had higher methylation levels but lower expression levels, which suggest that these non-additively expressed siRNA clusters, reduced the activity of transposable elements through DNA methylation in the hybrid. CONCLUSIONS These multi-omics data provide insights into how changes in epigenetic mechanisms and gene expression patterns can lead to heterosis in allopolyploid cotton. This makes heterosis a viable tool in cotton breeding.
Collapse
Affiliation(s)
- Rasmieh Hamid
- Department of Plant Breeding, Cotton Research Institute of Iran (CRII), Agricultural Research, Education and Extension Organization (AREEO), Gorgan, Iran.
| | - Feba Jacob
- Centre for Plant Biotechnology and Molecular Biology, Kerala Agricultural University, Thrissur, India
| | - Zahra Ghorbanzadeh
- Department of Systems Biology, Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
| | - Leila Jafari
- Horticultural Science Department, Faculty of Agriculture and Natural Resources, University of Hormozgan, Bandar Abbas, Iran
- Research Group of Agroecology in Dryland Areas, University of Hormozgan, Bandar Abbas, Iran
| | - Omran Alishah
- Department of Plant Breeding, Cotton Research Institute of Iran (CRII), Agricultural Research, Education and Extension Organization (AREEO), Gorgan, Iran
| |
Collapse
|
9
|
Zhang P, Mbodj A, Soundiramourtty A, Llauro C, Ghesquière A, Ingouff M, Keith Slotkin R, Pontvianne F, Catoni M, Mirouze M. Extrachromosomal circular DNA and structural variants highlight genome instability in Arabidopsis epigenetic mutants. Nat Commun 2023; 14:5236. [PMID: 37640706 PMCID: PMC10462705 DOI: 10.1038/s41467-023-41023-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 08/21/2023] [Indexed: 08/31/2023] Open
Abstract
Abundant extrachromosomal circular DNA (eccDNA) is associated with transposable element (TE) activity. However, how the eccDNA compartment is controlled by epigenetic regulations and what is its impact on the genome is understudied. Here, using long reads, we sequence both the eccDNA compartment and the genome of Arabidopsis thaliana mutant plants affected in DNA methylation and post-transcriptional gene silencing. We detect a high load of TE-derived eccDNA with truncated and chimeric forms. On the genomic side, on top of truncated and full length TE neo-insertions, we detect complex structural variations (SVs) notably at a disease resistance cluster being a natural hotspot of SV. Finally, we serendipitously identify large tandem duplications in hypomethylated plants, suggesting that SVs could have been overlooked in epigenetic mutants. We propose that a high eccDNA load may alter DNA repair pathways leading to genome instability and the accumulation of SVs, at least in plants.
Collapse
Affiliation(s)
- Panpan Zhang
- Institut de Recherche pour le Développement (IRD), Laboratory of Plant Genome and Development, Perpignan, France
- EMR269 MANGO (CNRS/IRD/UPVD), Laboratory of Plant Genome and Development, Perpignan, France
- University of Montpellier, Montpellier, France
| | - Assane Mbodj
- Institut de Recherche pour le Développement (IRD), Laboratory of Plant Genome and Development, Perpignan, France
- EMR269 MANGO (CNRS/IRD/UPVD), Laboratory of Plant Genome and Development, Perpignan, France
| | - Abirami Soundiramourtty
- EMR269 MANGO (CNRS/IRD/UPVD), Laboratory of Plant Genome and Development, Perpignan, France
- University of Perpignan, Perpignan, France
| | - Christel Llauro
- EMR269 MANGO (CNRS/IRD/UPVD), Laboratory of Plant Genome and Development, Perpignan, France
- Centre National de la Recherche Scientifique (CNRS), Laboratory of Plant Genome and Development, Perpignan, France
| | - Alain Ghesquière
- DIADE, University of Montpellier, IRD, CIRAD, Montpellier, France
| | - Mathieu Ingouff
- DIADE, University of Montpellier, IRD, CIRAD, Montpellier, France
| | - R Keith Slotkin
- Donald Danforth Plant Science Center, St. Louis, MO, 63132, USA
- Division of Biological Sciences, University of Missouri, Columbia, MO, 65211, USA
| | - Frédéric Pontvianne
- Centre National de la Recherche Scientifique (CNRS), Laboratory of Plant Genome and Development, Perpignan, France
| | - Marco Catoni
- School of Biosciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Marie Mirouze
- Institut de Recherche pour le Développement (IRD), Laboratory of Plant Genome and Development, Perpignan, France.
- EMR269 MANGO (CNRS/IRD/UPVD), Laboratory of Plant Genome and Development, Perpignan, France.
| |
Collapse
|
10
|
Epigenetic Changes Occurring in Plant Inbreeding. Int J Mol Sci 2023; 24:ijms24065407. [PMID: 36982483 PMCID: PMC10048984 DOI: 10.3390/ijms24065407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/01/2023] [Accepted: 03/10/2023] [Indexed: 03/18/2023] Open
Abstract
Inbreeding is the crossing of closely related individuals in nature or a plantation or self-pollinating plants, which produces plants with high homozygosity. This process can reduce genetic diversity in the offspring and decrease heterozygosity, whereas inbred depression (ID) can often reduce viability. Inbred depression is common in plants and animals and has played a significant role in evolution. In the review, we aim to show that inbreeding can, through the action of epigenetic mechanisms, affect gene expression, resulting in changes in the metabolism and phenotype of organisms. This is particularly important in plant breeding because epigenetic profiles can be linked to the deterioration or improvement of agriculturally important characteristics.
Collapse
|
11
|
Ma M, Zhong W, Zhang Q, Deng L, Wen J, Yi B, Tu J, Fu T, Zhao L, Shen J. Genome-wide analysis of transcriptome and histone modifications in Brassica napus hybrid. FRONTIERS IN PLANT SCIENCE 2023; 14:1123729. [PMID: 36778699 PMCID: PMC9911877 DOI: 10.3389/fpls.2023.1123729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 01/16/2023] [Indexed: 06/18/2023]
Abstract
Although utilization of heterosis has largely improved the yield of many crops worldwide, the underlying molecular mechanism of heterosis, particularly for allopolyploids, remains unclear. Here, we compared epigenome and transcriptome data of an elite hybrid and its parental lines in three assessed tissues (seedling, flower bud, and silique) to explore their contribution to heterosis in allopolyploid B. napus. Transcriptome analysis illustrated that a small proportion of non-additive genes in the hybrid compared with its parents, as well as parental expression level dominance, might have a significant effect on heterosis. We identified histone modification (H3K4me3 and H3K27me3) variation between the parents and hybrid, most of which resulted from the differences between parents. H3K4me3 variations were positively correlated with gene expression differences among the hybrid and its parents. Furthermore, H3K4me3 and H3K27me3 were rather stable in hybridization and were mainly inherited additively in the B. napus hybrid. Together, our data revealed that transcriptome reprogramming and histone modification remodeling in the hybrid could serve as valuable resources for better understanding heterosis in allopolyploid crops.
Collapse
|
12
|
Zhan W, Guo G, Cui L, Rashid MAR, Jiang L, Sun G, Yang J, Zhang Y. Combined transcriptome and metabolome analysis reveals the effects of light quality on maize hybrids. BMC PLANT BIOLOGY 2023; 23:41. [PMID: 36653749 PMCID: PMC9847186 DOI: 10.1186/s12870-023-04059-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
BACKGROUND Heterosis, or hybrid vigor, refers to the phenotypic superiority of an F1 hybrid relative to its parents in terms of growth rate, biomass production, grain yield, and stress tolerance. Light is an energy source and main environmental cue with marked impacts on heterosis in plants. Research into the production applications and mechanism of heterosis has been conducted for over a century and a half, but little is known about the effect of light on plant heterosis. RESULTS In this study, an integrated transcriptome and metabolome analysis was performed using maize (Zea mays L.) inbred parents, B73 and Mo17, and their hybrids, B73 × Mo17 (BM) and Mo17 × B73 (MB), grown in darkness or under far-red, red, or blue light. Most differentially expressed genes (73.72-92.50%) and differentially accumulated metabolites (84.74-94.32%) exhibited non-additive effects in BM and MB hybrids. Gene Ontology analysis revealed that differential genes and metabolites were involved in glutathione transfer, carbohydrate transport, terpenoid biosynthesis, and photosynthesis. The darkness, far-red, red, and blue light treatments were all associated with phenylpropanoid-flavonoid biosynthesis by Weighted Gene Co-expression Network Analysis and Kyoto Encyclopedia of Genes and Genomes enrichment analysis. Five genes and seven metabolites related to phenylpropanoid-flavonoid biosynthesis pathway were identified as potential contributors to the interactions between maize heterosis and light conditions. Consistent with the strong mid-parent heterosis observed for metabolites, significant increases in both fresh and dry weights were found in the MB and BM hybrids compared with their inbred parents. Unexpectedly, increasing light intensity resulted in higher biomass heterosis in MB, but lower biomass heterosis in BM. CONCLUSIONS The transcriptomic and metabolomic results provide unique insights into the effects of light quality on gene expression patterns and genotype-environment interactions, and have implications for gene mining of heterotic loci to improve maize production.
Collapse
Affiliation(s)
- Weimin Zhan
- State Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
| | - Guanghui Guo
- State Key Laboratory of Crop Stress Adaptation and Improvement, College of Agriculture, Henan University, Kaifeng, 475004, China
| | - Lianhua Cui
- State Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
| | - Muhammad Abdul Rehman Rashid
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, 38000, Pakistan
| | - Liangliang Jiang
- State Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
| | - Guanghua Sun
- State Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Jianping Yang
- State Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Yanpei Zhang
- State Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China.
| |
Collapse
|
13
|
Identification of quantitative trait loci for growth traits in red swamp crayfish (Procambarus clarkii). AQUACULTURE AND FISHERIES 2023. [DOI: 10.1016/j.aaf.2023.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
14
|
Abstract
Introducing asexual reproduction through seeds - apomixis - into crop species could revolutionize agriculture by allowing F1 hybrids with enhanced yield and stability to be clonally propagated. Engineering synthetic apomixis has proven feasible in inbred rice through the inactivation of three genes (MiMe), which results in the conversion of meiosis into mitosis in a line ectopically expressing the BABYBOOM1 (BBM1) parthenogenetic trigger in egg cells. However, only 10-30% of the seeds are clonal. Here, we show that synthetic apomixis can be achieved in an F1 hybrid of rice by inducing MiMe mutations and egg cell expression of BBM1 in a single step. We generate hybrid plants that produce more than 95% of clonal seeds across multiple generations. Clonal apomictic plants maintain the phenotype of the F1 hybrid along successive generations. Our results demonstrate that there is no barrier to almost fully penetrant synthetic apomixis in an important crop species, rendering it compatible with use in agriculture.
Collapse
|
15
|
Zhang F, Ding Y, Zhang J, Tang M, Cao Y, Zhang L, Ma Z, Qi J, Mu X, Xia L, Tang B. Comparative transcriptomic reveals the molecular mechanism of maize hybrid Zhengdan538 in response to water deficit. PHYSIOLOGIA PLANTARUM 2022; 174:e13818. [PMID: 36345780 DOI: 10.1111/ppl.13818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 09/23/2022] [Accepted: 10/31/2022] [Indexed: 06/16/2023]
Abstract
Heterosis, known as one of the most successful strategies for increasing grain yield and abiotic/biotic stress tolerance, has been widely exploited in maize breeding. However, the underlying molecular processes are still to be elucidated. The maize hybrid "Zhengdan538" shows high tolerance to drought stress. The transcriptomes of the seedling leaves of its parents, "ZhengA88" and "ZhengT22" and their reciprocal F1 hybrid under well-watered and water deficit conditions, were analyzed by RNA sequencing (RNA-Seq). Transcriptome profiling of the reciprocal hybrid revealed 2994-4692 differentially expressed genes (DEGs) under well-watered and water-deficit conditions, which were identified by comparing with their parents. The reciprocal hybrid was more closely related to the parental line "ZhengT22" than to the parental line "ZhengA88" in terms of gene expression patterns under water-deficit condition. Furthermore, genes showed expression level dominance (ELD), especially the high-parental ELD (Class 3 and 5), accounted for the largest proportion of DEGs between the reciprocal F1 hybrid and their parental lines under water deficit. These ELD genes mainly participated in photosynthesis, energy biosynthesis, and metabolism processes. The results indicated that ELD genes played important roles in hybrid tolerance to water deficit. Moreover, a set of important drought-responsive transcription factors were found to be encoded by the identified ELD genes and are thought to function in improving drought tolerance in maize hybrid plants. Our results provide a better understanding of the molecular mechanism of drought tolerance in hybrid maize.
Collapse
Affiliation(s)
- Fengqi Zhang
- Cereal Crops Research Institute, Henan Academy of Agricultural Sciences/Henan Provincial Key Laboratory of Maize Biology/Henan International Joint Laboratory on Maize Precision Production, Zhengzhou, China
| | - Yong Ding
- Cereal Crops Research Institute, Henan Academy of Agricultural Sciences/Henan Provincial Key Laboratory of Maize Biology/Henan International Joint Laboratory on Maize Precision Production, Zhengzhou, China
| | - Jun Zhang
- Cereal Crops Research Institute, Henan Academy of Agricultural Sciences/Henan Provincial Key Laboratory of Maize Biology/Henan International Joint Laboratory on Maize Precision Production, Zhengzhou, China
| | - Minqiang Tang
- The Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants (Ministry of Education), College of Forestry, Hainan University, Haikou, China
| | - Yanyong Cao
- Cereal Crops Research Institute, Henan Academy of Agricultural Sciences/Henan Provincial Key Laboratory of Maize Biology/Henan International Joint Laboratory on Maize Precision Production, Zhengzhou, China
| | - Lanxun Zhang
- Cereal Crops Research Institute, Henan Academy of Agricultural Sciences/Henan Provincial Key Laboratory of Maize Biology/Henan International Joint Laboratory on Maize Precision Production, Zhengzhou, China
| | - Zhiyan Ma
- Cereal Crops Research Institute, Henan Academy of Agricultural Sciences/Henan Provincial Key Laboratory of Maize Biology/Henan International Joint Laboratory on Maize Precision Production, Zhengzhou, China
| | - Jianshuang Qi
- Cereal Crops Research Institute, Henan Academy of Agricultural Sciences/Henan Provincial Key Laboratory of Maize Biology/Henan International Joint Laboratory on Maize Precision Production, Zhengzhou, China
| | - Xinyuan Mu
- Cereal Crops Research Institute, Henan Academy of Agricultural Sciences/Henan Provincial Key Laboratory of Maize Biology/Henan International Joint Laboratory on Maize Precision Production, Zhengzhou, China
| | - Laikun Xia
- Cereal Crops Research Institute, Henan Academy of Agricultural Sciences/Henan Provincial Key Laboratory of Maize Biology/Henan International Joint Laboratory on Maize Precision Production, Zhengzhou, China
| | - Baojun Tang
- Cereal Crops Research Institute, Henan Academy of Agricultural Sciences/Henan Provincial Key Laboratory of Maize Biology/Henan International Joint Laboratory on Maize Precision Production, Zhengzhou, China
| |
Collapse
|
16
|
Jaiswal V, Rawoof A, Gahlaut V, Ahmad I, Chhapekar SS, Dubey M, Ramchiary N. Integrated analysis of DNA methylation, transcriptome, and global metabolites in interspecific heterotic Capsicum F 1 hybrid. iScience 2022; 25:105318. [PMID: 36304106 PMCID: PMC9593261 DOI: 10.1016/j.isci.2022.105318] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 06/04/2022] [Accepted: 10/06/2022] [Indexed: 11/19/2022] Open
Abstract
Hybrid breeding is one of the efficacious methods of crop improvement. Here, we report our work towards understanding the molecular basis of F1 hybrid heterosis from Capsicum chinense and C. frutescens cross. Bisulfite sequencing identified a total of 70597 CG, 108797 CHG, and 38418 CHH differentially methylated regions (DMRs) across F1 hybrid and parents, and of these, 4891 DMRs showed higher methylation in F1 compared to the mid-parental methylation values (MPMV). Transcriptome analysis showed higher expression of 46–55% differentially expressed genes (DE-Gs) in the F1 hybrid. The qRT-PCR analysis of 24 DE-Gs with negative promoter methylation revealed 91.66% expression similarity with the transcriptome data. A few metabolites and 65–72% enriched genes in metabolite biosynthetic pathways showed overall increased expression in the F1 hybrid compared to parents. These findings, taken together, provided insights into the integrated role of DNA methylation, and genes and metabolites expression in the manifestation of heterosis in Capsicum. Global methylation identified significantly different proportions of mCs in hybrid Of common DMRs, 33.08% showed different methylation in hybrid from the mid-parental value Negatively correlated DEG pDMR-genes were enriched in metabolic pathways Significant higher expression of metabolites and DE-Gs were identified in the F1 hybrid
Collapse
Affiliation(s)
- Vandana Jaiswal
- Translational and Evolutionary Genomics Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh, India
- Corresponding author
| | - Abdul Rawoof
- Translational and Evolutionary Genomics Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Vijay Gahlaut
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh, India
| | - Ilyas Ahmad
- Translational and Evolutionary Genomics Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Sushil S. Chhapekar
- Translational and Evolutionary Genomics Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
- Department of Horticulture, Chungnam National University, Daejeon 34134, South Korea
| | - Meenakshi Dubey
- Translational and Evolutionary Genomics Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
- Department of Biotechnology, Delhi Technological University, Shahbad Daulatpur, Bawana Road, Delhi 110042, India
| | - Nirala Ramchiary
- Translational and Evolutionary Genomics Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
- Corresponding author
| |
Collapse
|
17
|
Tonosaki K, Fujimoto R, Dennis ES, Raboy V, Osabe K. Will epigenetics be a key player in crop breeding? FRONTIERS IN PLANT SCIENCE 2022; 13:958350. [PMID: 36247549 PMCID: PMC9562705 DOI: 10.3389/fpls.2022.958350] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 09/12/2022] [Indexed: 06/16/2023]
Abstract
If food and feed production are to keep up with world demand in the face of climate change, continued progress in understanding and utilizing both genetic and epigenetic sources of crop variation is necessary. Progress in plant breeding has traditionally been thought to be due to selection for spontaneous DNA sequence mutations that impart desirable phenotypes. These spontaneous mutations can expand phenotypic diversity, from which breeders can select agronomically useful traits. However, it has become clear that phenotypic diversity can be generated even when the genome sequence is unaltered. Epigenetic gene regulation is a mechanism by which genome expression is regulated without altering the DNA sequence. With the development of high throughput DNA sequencers, it has become possible to analyze the epigenetic state of the whole genome, which is termed the epigenome. These techniques enable us to identify spontaneous epigenetic mutations (epimutations) with high throughput and identify the epimutations that lead to increased phenotypic diversity. These epimutations can create new phenotypes and the causative epimutations can be inherited over generations. There is evidence of selected agronomic traits being conditioned by heritable epimutations, and breeders may have historically selected for epiallele-conditioned agronomic traits. These results imply that not only DNA sequence diversity, but the diversity of epigenetic states can contribute to increased phenotypic diversity. However, since the modes of induction and transmission of epialleles and their stability differ from that of genetic alleles, the importance of inheritance as classically defined also differs. For example, there may be a difference between the types of epigenetic inheritance important to crop breeding and crop production. The former may depend more on longer-term inheritance whereas the latter may simply take advantage of shorter-term phenomena. With the advances in our understanding of epigenetics, epigenetics may bring new perspectives for crop improvement, such as the use of epigenetic variation or epigenome editing in breeding. In this review, we will introduce the role of epigenetic variation in plant breeding, largely focusing on DNA methylation, and conclude by asking to what extent new knowledge of epigenetics in crop breeding has led to documented cases of its successful use.
Collapse
Affiliation(s)
- Kaoru Tonosaki
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
| | - Ryo Fujimoto
- Graduate School of Agricultural Science, Kobe University, Kobe, Japan
| | - Elizabeth S. Dennis
- Commonwealth Scientific and Industrial Research Organisation (CSIRO) Agriculture and Food, Canberra, ACT, Australia
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - Victor Raboy
- Independent Researcher Portland, Portland, OR, United States
| | - Kenji Osabe
- Institute of Scientific and Industrial Research (SANKEN), Osaka University, Osaka, Japan
| |
Collapse
|
18
|
De Kort H, Toivainen T, Van Nieuwerburgh F, Andrés J, Hytönen TP, Honnay O. Signatures of polygenic adaptation align with genome-wide methylation patterns in wild strawberry plants. THE NEW PHYTOLOGIST 2022; 235:1501-1514. [PMID: 35575945 DOI: 10.1111/nph.18225] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 04/29/2022] [Indexed: 06/15/2023]
Abstract
Epigenetic inheritance can drive adaptive evolution independently of DNA sequence variation. However, to what extent epigenetic variation represents an autonomous evolutionary force remains largely elusive. Through gene ontology and comparative analyses of genomic and epigenomic variation of wild strawberry plants raised in distinct drought settings, we characterised genome-wide covariation between single nucleotide polymorphisms (SNPs) and differentially methylated cytosines (DMCs). Covariation between SNPs and DMCs was independent of genomic proximity, but instead associated with fitness-related processes such as stress responses, genome regulation and reproduction. We expected this functional SNP-DMC covariation to be driven by adaptive evolution canalising SNP and DMC variation, but instead observed significantly lower covariation with DMCs for adaptive rather than for neutral SNPs. Drought-induced DMCs frequently co-varied with tens of SNPs, suggesting high genomic redundancy as a broad potential basis for polygenic adaptation of gene expression. Our findings suggest that stress-responsive DMCs initially co-vary with many SNPs under increased environmental stress, and that natural selection acting upon several of these SNPs subsequently reduces standing covariation with stress-responsive DMCs. Our study supports DNA methylation profiles that represent complex quantitative traits rather than autonomous evolutionary forces. We provide a conceptual framework for polygenic regulation and adaptation shaping genome-wide methylation patterns in plants.
Collapse
Affiliation(s)
- Hanne De Kort
- Plant Conservation and Population Biology, University of Leuven, Kasteelpark Arenberg 31-2435, BE-3001, Leuven, Belgium
| | - Tuomas Toivainen
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, Latokartanonkaari 7, 00790, Helsinki, Finland
| | | | - Javier Andrés
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, Latokartanonkaari 7, 00790, Helsinki, Finland
| | - Timo P Hytönen
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, Latokartanonkaari 7, 00790, Helsinki, Finland
| | - Olivier Honnay
- Plant Conservation and Population Biology, University of Leuven, Kasteelpark Arenberg 31-2435, BE-3001, Leuven, Belgium
| |
Collapse
|
19
|
Li T, Wang F, Yasir M, Li K, Qin Y, Zheng J, Luo K, Zhu S, Zhang H, Jiang Y, Zhang Y, Rong J. Expression Patterns Divergence of Reciprocal F 1 Hybrids Between Gossypium hirsutum and Gossypium barbadense Reveals Overdominance Mediating Interspecific Biomass Heterosis. FRONTIERS IN PLANT SCIENCE 2022; 13:892805. [PMID: 35845678 PMCID: PMC9284264 DOI: 10.3389/fpls.2022.892805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 06/06/2022] [Indexed: 06/15/2023]
Abstract
Hybrid breeding has provided an impetus to the process and achievement of a higher yield and quality of crops. Interspecific hybridization is critical for resolving parental genetic diversity bottleneck problems. The reciprocal interspecific hybrids and their parents (Gossypium hirsutum and Gossypium barbadense) have been applied in this study to elucidate the transcription regulatory mechanism of early biomass heterosis. Phenotypically, the seed biomass, plant height over parent heterosis, leaf area over parent heterosis, and fresh and dry biomass were found to be significantly higher in hybrids than in parents. Analysis of leaf areas revealed that the one-leaf stage exhibits the most significant performance in initial vegetative growth vigor and larger leaves in hybrids, increasing the synthesis of photosynthesis compounds and enhancing photosynthesis compound synthesis. Comparative transcriptome analysis showed that transgressive down-regulation (TDR) is the main gene expression pattern in the hybrids (G. hirsutum × G. barbadense, HB), and it was found that the genes of photosystem I and Adenosine triphosphate (ATP)-binding may promote early growth vigor. Transgressive up-regulation (TUR) is the major primary gene expression pattern in the hybrids (G. barbadense × G. hirsutum, BH), and photosystem II-related genes mediated the performance of early biomass heterosis. The above results demonstrated that overdominance mediates biomass heterosis in interspecific hybrid cotton and the supervisory mechanism divergence of hybrids with different females. Photosynthesis and other metabolic process are jointly involved in controlling early biomass heterosis in interspecific hybrid cotton. The expression pattern data of transcriptome sequencing were supported using the qRT-PCR analysis. Our findings could be useful in theoretical and practical studies of early interspecific biomass heterosis, and the results provide potential resources for the theoretical and applied research on early interspecific biomass heterosis.
Collapse
Affiliation(s)
- Tengyu Li
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, Zhejiang Agriculture and Forestry University, Hangzhou, China
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Fuqiu Wang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Muhammad Yasir
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, Zhejiang Agriculture and Forestry University, Hangzhou, China
| | - Kui Li
- Institute of Food and Nutrition Development, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yuan Qin
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Jing Zheng
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, Zhejiang Agriculture and Forestry University, Hangzhou, China
| | - Kun Luo
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, Zhejiang Agriculture and Forestry University, Hangzhou, China
| | - Shouhong Zhu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Hua Zhang
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, Zhejiang Agriculture and Forestry University, Hangzhou, China
| | - Yurong Jiang
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, Zhejiang Agriculture and Forestry University, Hangzhou, China
| | - Yongshan Zhang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Junkang Rong
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, Zhejiang Agriculture and Forestry University, Hangzhou, China
| |
Collapse
|
20
|
|
21
|
Cerruti E, Gisbert C, Drost HG, Valentino D, Portis E, Barchi L, Prohens J, Lanteri S, Comino C, Catoni M. Grafting vigour is associated with DNA de-methylation in eggplant. HORTICULTURE RESEARCH 2021; 8:241. [PMID: 34719687 PMCID: PMC8558322 DOI: 10.1038/s41438-021-00660-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 07/20/2021] [Accepted: 07/30/2021] [Indexed: 05/08/2023]
Abstract
In horticulture, grafting is a popular technique used to combine positive traits from two different plants. This is achieved by joining the plant top part (scion) onto a rootstock which contains the stem and roots. Rootstocks can provide resistance to stress and increase plant production, but despite their wide use, the biological mechanisms driving rootstock-induced alterations of the scion phenotype remain largely unknown. Given that epigenetics plays a relevant role during distance signalling in plants, we studied the genome-wide DNA methylation changes induced in eggplant (Solanum melongena) scion using two interspecific rootstocks to increase vigour. We found that vigour was associated with a change in scion gene expression and a genome-wide hypomethylation in the CHH context. Interestingly, this hypomethylation correlated with the downregulation of younger and potentially more active long terminal repeat retrotransposable elements (LTR-TEs), suggesting that graft-induced epigenetic modifications are associated with both physiological and molecular phenotypes in grafted plants. Our results indicate that the enhanced vigour induced by heterografting in eggplant is associated with epigenetic modifications, as also observed in some heterotic hybrids.
Collapse
Affiliation(s)
- Elisa Cerruti
- Department of Agricultural, Forest and Food Sciences, Plant Genetics and Breeding, University of Torino, Grugliasco, Italy
- The Sainsbury Laboratory, University of Cambridge, Cambridge, UK
| | - Carmina Gisbert
- Institute for Conservation & Improvement of Valencian Agrodiversity (COMAV), Universitat Politècnica de València, Valencia, Spain
| | - Hajk-Georg Drost
- The Sainsbury Laboratory, University of Cambridge, Cambridge, UK
- Computational Biology Group, Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Danila Valentino
- Department of Agricultural, Forest and Food Sciences, Plant Genetics and Breeding, University of Torino, Grugliasco, Italy
| | - Ezio Portis
- Department of Agricultural, Forest and Food Sciences, Plant Genetics and Breeding, University of Torino, Grugliasco, Italy
| | - Lorenzo Barchi
- Department of Agricultural, Forest and Food Sciences, Plant Genetics and Breeding, University of Torino, Grugliasco, Italy
| | - Jaime Prohens
- Institute for Conservation & Improvement of Valencian Agrodiversity (COMAV), Universitat Politècnica de València, Valencia, Spain
| | - Sergio Lanteri
- Department of Agricultural, Forest and Food Sciences, Plant Genetics and Breeding, University of Torino, Grugliasco, Italy
| | - Cinzia Comino
- Department of Agricultural, Forest and Food Sciences, Plant Genetics and Breeding, University of Torino, Grugliasco, Italy.
| | - Marco Catoni
- The Sainsbury Laboratory, University of Cambridge, Cambridge, UK.
- School of Biosciences, University of Birmingham, Birmingham, United Kingdom.
- Institute for Sustainable Plant Protection, National Research Council of Italy, Torino, Italy.
| |
Collapse
|
22
|
Wu J, Sun D, Zhao Q, Yong H, Zhang D, Hao Z, Zhou Z, Han J, Zhang X, Xu Z, Li X, Li M, Weng J. Transcriptome Reveals Allele Contribution to Heterosis in Maize. FRONTIERS IN PLANT SCIENCE 2021; 12:739072. [PMID: 34630491 PMCID: PMC8494984 DOI: 10.3389/fpls.2021.739072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Accepted: 09/06/2021] [Indexed: 06/13/2023]
Abstract
Heterosis, which has greatly increased maize yields, is associated with gene expression patterns during key developmental stages that enhance hybrid phenotypes relative to parental phenotypes. Before heterosis can be more effectively used for crop improvement, hybrid maize developmental gene expression patterns must be better understood. Here, six maize hybrids, including the popular hybrid Zhengdan958 (ZC) from China, were studied. Maize hybrids created in-house were generated using an incomplete diallel cross (NCII)-based strategy from four elite inbred parental lines. Differential gene expression (DEG) profiles corresponding to three developmental stages revealed that hybrid partial expression patterns exhibited complementarity of expression of certain parental genes, with parental allelic expression patterns varying both qualitatively and quantitatively in hybrids. Single-parent expression (SPE) and parent-specific expression (PSE) types of qualitative variation were most prevalent, 43.73 and 41.07% of variation, respectively. Meanwhile, negative super-dominance (NSD) and positive super-dominance (PSD) types of quantitative variation were most prevalent, 31.06 and 24.30% of variation, respectively. During the early reproductive growth stage, the gene expression pattern differed markedly from other developmental stage patterns, with allelic expression patterns during seed development skewed toward low-value parental alleles in hybrid seeds exhibiting significant quantitative variation-associated superiority. Comparisons of qualitative gene expression variation rates between ZC and other hybrids revealed proportions of SPE-DEGs (41.36%) in ZC seed DEGs that significantly exceeded the average proportion of SPE-DEGs found in seeds of other hybrids (28.36%). Importantly, quantitative gene expression variation rate comparisons between ZC and hybrids, except for transgressive expression, revealed that the ZC rate exceeded the average rate for other hybrids, highlighting the importance of partial gene expression in heterosis. Moreover, enriched ZC DEGs exhibiting distinct tissue-specific expression patterns belonged to four biological pathways, including photosynthesis, plant hormone signal transduction, biology metabolism and biosynthesis. These results provide valuable technical insights for creating hybrids exhibiting strong heterosis.
Collapse
Affiliation(s)
- Jianzhong Wu
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
- Institute of Forage and Grassland Sciences, Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Dequan Sun
- Institute of Forage and Grassland Sciences, Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Qian Zhao
- Institute of Crop Cultivation and Tillage, Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Hongjun Yong
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Degui Zhang
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhuanfang Hao
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhiqiang Zhou
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jienan Han
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiaocong Zhang
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhennan Xu
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xinhai Li
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Mingshun Li
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jianfeng Weng
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| |
Collapse
|
23
|
Kakoulidou I, Avramidou EV, Baránek M, Brunel-Muguet S, Farrona S, Johannes F, Kaiserli E, Lieberman-Lazarovich M, Martinelli F, Mladenov V, Testillano PS, Vassileva V, Maury S. Epigenetics for Crop Improvement in Times of Global Change. BIOLOGY 2021; 10:766. [PMID: 34439998 PMCID: PMC8389687 DOI: 10.3390/biology10080766] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/04/2021] [Accepted: 08/06/2021] [Indexed: 12/15/2022]
Abstract
Epigenetics has emerged as an important research field for crop improvement under the on-going climatic changes. Heritable epigenetic changes can arise independently of DNA sequence alterations and have been associated with altered gene expression and transmitted phenotypic variation. By modulating plant development and physiological responses to environmental conditions, epigenetic diversity-naturally, genetically, chemically, or environmentally induced-can help optimise crop traits in an era challenged by global climate change. Beyond DNA sequence variation, the epigenetic modifications may contribute to breeding by providing useful markers and allowing the use of epigenome diversity to predict plant performance and increase final crop production. Given the difficulties in transferring the knowledge of the epigenetic mechanisms from model plants to crops, various strategies have emerged. Among those strategies are modelling frameworks dedicated to predicting epigenetically controlled-adaptive traits, the use of epigenetics for in vitro regeneration to accelerate crop breeding, and changes of specific epigenetic marks that modulate gene expression of traits of interest. The key challenge that agriculture faces in the 21st century is to increase crop production by speeding up the breeding of resilient crop species. Therefore, epigenetics provides fundamental molecular information with potential direct applications in crop enhancement, tolerance, and adaptation within the context of climate change.
Collapse
Affiliation(s)
- Ioanna Kakoulidou
- Department of Molecular Life Sciences, Technical University of Munich, Liesel-Beckmann-Str. 2, 85354 Freising, Germany; (I.K.); (F.J.)
| | - Evangelia V. Avramidou
- Laboratory of Forest Genetics and Biotechnology, Institute of Mediterranean Forest Ecosystems, Hellenic Agricultural Organization-Dimitra (ELGO-DIMITRA), 11528 Athens, Greece;
| | - Miroslav Baránek
- Faculty of Horticulture, Mendeleum—Institute of Genetics, Mendel University in Brno, Valtická 334, 69144 Lednice, Czech Republic;
| | - Sophie Brunel-Muguet
- UMR 950 Ecophysiologie Végétale, Agronomie et Nutritions N, C, S, UNICAEN, INRAE, Normandie Université, CEDEX, F-14032 Caen, France;
| | - Sara Farrona
- Plant and AgriBiosciences Centre, Ryan Institute, National University of Ireland (NUI) Galway, H91 TK33 Galway, Ireland;
| | - Frank Johannes
- Department of Molecular Life Sciences, Technical University of Munich, Liesel-Beckmann-Str. 2, 85354 Freising, Germany; (I.K.); (F.J.)
- Institute for Advanced Study, Technical University of Munich, Lichtenberg Str. 2a, 85748 Garching, Germany
| | - Eirini Kaiserli
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow G12 8QQ, UK;
| | - Michal Lieberman-Lazarovich
- Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel;
| | - Federico Martinelli
- Department of Biology, University of Florence, 50019 Sesto Fiorentino, Italy;
| | - Velimir Mladenov
- Faculty of Agriculture, University of Novi Sad, Sq. Dositeja Obradovića 8, 21000 Novi Sad, Serbia;
| | - Pilar S. Testillano
- Pollen Biotechnology of Crop Plants Group, Centro de Investigaciones Biológicas Margarita Salas-(CIB-CSIC), Ramiro Maeztu 9, 28040 Madrid, Spain;
| | - Valya Vassileva
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Bldg. 21, 1113 Sofia, Bulgaria;
| | - Stéphane Maury
- Laboratoire de Biologie des Ligneux et des Grandes Cultures, INRAE, EA1207 USC1328, Université d’Orléans, F-45067 Orléans, France
| |
Collapse
|
24
|
Han T, Wang F, Song Q, Ye W, Liu T, Wang L, Chen ZJ. An epigenetic basis of inbreeding depression in maize. SCIENCE ADVANCES 2021; 7:7/35/eabg5442. [PMID: 34452913 PMCID: PMC8397266 DOI: 10.1126/sciadv.abg5442] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 07/07/2021] [Indexed: 05/12/2023]
Abstract
Inbreeding depression is widespread across plant and animal kingdoms and may arise from the exposure of deleterious alleles and/or loss of overdominant alleles resulting from increased homozygosity, but these genetic models cannot fully explain the phenomenon. Here, we report epigenetic links to inbreeding depression in maize. Teosinte branched1/cycloidea/proliferating cell factor (TCP) transcription factors control plant development. During successive inbreeding among inbred lines, thousands of genomic regions across TCP-binding sites (TBS) are hypermethylated through the H3K9me2-mediated pathway. These hypermethylated regions are accompanied by decreased chromatin accessibility, increased levels of the repressive histone marks H3K27me2 and H3K27me3, and reduced binding affinity of maize TCP-proteins to TBS. Consequently, hundreds of TCP-target genes involved in mitochondrion, chloroplast, and ribosome functions are down-regulated, leading to reduced growth vigor. Conversely, random mating can reverse corresponding hypermethylation sites and TCP-target gene expression, restoring growth vigor. These results support a unique role of reversible epigenetic modifications in inbreeding depression.
Collapse
Affiliation(s)
- Tongwen Han
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, 1 Weigang Road, Nanjing 210095, China
| | - Fang Wang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, 1 Weigang Road, Nanjing 210095, China
| | - Qingxin Song
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, 1 Weigang Road, Nanjing 210095, China
| | - Wenxue Ye
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, 1 Weigang Road, Nanjing 210095, China
| | - Tieshan Liu
- Maize Research Institute, Shandong Academy of Agricultural Sciences, Jinan 250100, China
| | - Liming Wang
- Maize Research Institute, Shandong Academy of Agricultural Sciences, Jinan 250100, China
| | - Z Jeffrey Chen
- Department of Molecular Biosciences and Center for Computational Biology and Bioinformatics, The University of Texas at Austin, Austin, TX 78712, USA.
| |
Collapse
|
25
|
Ma X, Xing F, Jia Q, Zhang Q, Hu T, Wu B, Shao L, Zhao Y, Zhang Q, Zhou DX. Parental variation in CHG methylation is associated with allelic-specific expression in elite hybrid rice. PLANT PHYSIOLOGY 2021; 186:1025-1041. [PMID: 33620495 PMCID: PMC8195538 DOI: 10.1093/plphys/kiab088] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 01/28/2021] [Indexed: 05/19/2023]
Abstract
Heterosis refers to the superior performance of hybrid lines over inbred parental lines. Besides genetic variation, epigenetic differences between parental lines are suggested to contribute to heterosis. However, the precise nature and extent of differences between the parental epigenomes and the reprograming in hybrids that govern heterotic gene expression remain unclear. In this work, we analyzed DNA methylomes and transcriptomes of the widely cultivated and genetically studied elite hybrid rice (Oryza sativa) SY63, the reciprocal hybrid, and the parental varieties ZS97 and MH63, for which high-quality reference genomic sequences are available. We showed that the parental varieties displayed substantial variation in genic methylation at CG and CHG (H = A, C, or T) sequences. Compared with their parents, the hybrids displayed dynamic methylation variation during development. However, many parental differentially methylated regions (DMRs) at CG and CHG sites were maintained in the hybrid. Only a small fraction of the DMRs displayed non-additive DNA methylation variation, which, however, showed no overall correlation relationship with gene expression variation. In contrast, most of the allelic-specific expression (ASE) genes in the hybrid were associated with DNA methylation, and the ASE negatively associated with allelic-specific methylation (ASM) at CHG. These results revealed a specific DNA methylation reprogramming pattern in the hybrid rice and pointed to a role for parental CHG methylation divergence in ASE, which is associated with phenotype variation and hybrid vigor in several plant species.
Collapse
Affiliation(s)
- Xuan Ma
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, 430070 Wuhan, China
| | - Feng Xing
- College of Life Science, Xinyang Normal University, 464000 Xinyang, China
| | - Qingxiao Jia
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, 430070 Wuhan, China
| | - Qinglu Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, 430070 Wuhan, China
| | - Tong Hu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, 430070 Wuhan, China
| | - Baoguo Wu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, 430070 Wuhan, China
| | - Lin Shao
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, 430070 Wuhan, China
| | - Yu Zhao
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, 430070 Wuhan, China
| | - Qifa Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, 430070 Wuhan, China
| | - Dao-Xiu Zhou
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, 430070 Wuhan, China
- Institute of Plant Science Paris-Saclay (IPS2), CNRS, INRAE, University Paris-Saclay, 91405 Orsay, France
- Author for communication:
| |
Collapse
|
26
|
Epimutations and mutations, nurturing phenotypic diversity. Genetica 2021; 150:171-181. [PMID: 34114171 DOI: 10.1007/s10709-021-00124-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 05/26/2021] [Indexed: 12/22/2022]
Abstract
Epimutations and mutations are two dissimilar mechanisms that have contributed to the phenotypic diversities in organisms. Though dissimilar, many previous studies have revealed that the consequences of epimutations and mutations are not mutually exclusive. DNA rich in epigenetic modifications can be prone to mutations and vice versa. In order to get a better insight into the molecular evolution in organisms, it is important to consider the information of both genetic and epigenetic changes in their genomes. Understanding the similarities and differences between the consequences of epimutations and mutations is required for a better interpretation of phenotypic diversities in organisms. Factors contributing to epigenetic changes such as paramutations and mutation hotspots and, the correlation of the interdependence of mutations and epigenetic changes in DNA are important aspects that need to be considered for molecular evolutionary studies. Thus, this review explains what epimutations are, their causes, how they are similar/different from mutations, and the influence of epigenetic changes and mutations on each other, further emphasizing how molecular evolution involving both mutations and epimutations can lead to speciation. Considering this approach will aid in reorganizing taxonomic classifications, importantly, solving disparities in species identification.
Collapse
|
27
|
A central circadian oscillator confers defense heterosis in hybrids without growth vigor costs. Nat Commun 2021; 12:2317. [PMID: 33875651 PMCID: PMC8055661 DOI: 10.1038/s41467-021-22268-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 03/05/2021] [Indexed: 11/10/2022] Open
Abstract
Plant immunity frequently incurs growth penalties, which known as the trade-off between immunity and growth. Heterosis, the phenotypic superiority of a hybrid over its parents, has been demonstrated for many traits but rarely for disease resistance. Here, we report that the central circadian oscillator, CCA1, confers heterosis for bacterial defense in hybrids without growth vigor costs, and it even significantly enhances the growth heterosis of hybrids under pathogen infection. The genetic perturbation of CCA1 abrogated heterosis for both defense and growth in hybrids. Upon pathogen attack, the expression of CCA1 in F1 hybrids is precisely modulated at different time points during the day by its rhythmic histone modifications. Before dawn of the first infection day, epigenetic activation of CCA1 promotes an elevation of salicylic acid accumulation in hybrids, enabling heterosis for defense. During the middle of every infection day, diurnal epigenetic repression of CCA1 leads to rhythmically increased chlorophyll synthesis and starch metabolism in hybrids, effectively eliminating the immunity-growth heterosis trade-offs in hybrids. There is frequently a trade-off between plant immunity and growth. Here the authors show that the epigenetic control of CCA1, encoding a core component of the circadian oscillator, simultaneously promotes heterosis for both defense and growth in hybrids under pathogen invasion.
Collapse
|
28
|
Comparative Transcriptomic Analysis of Gene Expression Inheritance Patterns Associated with Cabbage Head Heterosis. PLANTS 2021; 10:plants10020275. [PMID: 33572601 PMCID: PMC7912167 DOI: 10.3390/plants10020275] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 01/27/2021] [Accepted: 01/27/2021] [Indexed: 11/16/2022]
Abstract
The molecular mechanism of heterosis or hybrid vigor, where F1 hybrids of genetically diverse parents show superior traits compared to their parents, is not well understood. Here, we studied the molecular regulation of heterosis in four F1 cabbage hybrids that showed heterosis for several horticultural traits, including head size and weight. To examine the molecular mechanisms, we performed a global transcriptome profiling in the hybrids and their parents by RNA sequencing. The proportion of genetic variations detected as single nucleotide polymorphisms and small insertion–deletions as well as the numbers of differentially expressed genes indicated a larger role of the female parent than the male parent in the genetic divergence of the hybrids. More than 86% of hybrid gene expressions were non-additive. More than 81% of the genes showing divergent expressions showed dominant inheritance, and more than 56% of these exhibited maternal expression dominance. Gene expression regulation by cis-regulatory mechanisms appears to mediate most of the gene expression divergence in the hybrids; however, trans-regulatory factors appear to have a higher effect compared to cis-regulatory factors on parental expression divergence. These observations bring new insights into the molecular mechanisms of heterosis during the cabbage head development.
Collapse
|
29
|
Fiaz S, Wang X, Younas A, Alharthi B, Riaz A, Ali H. Apomixis and strategies to induce apomixis to preserve hybrid vigor for multiple generations. GM CROPS & FOOD 2021; 12:57-70. [PMID: 32877304 PMCID: PMC7553744 DOI: 10.1080/21645698.2020.1808423] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 08/06/2020] [Indexed: 11/16/2022]
Abstract
Hybrid seeds of several important crops with supreme qualities including yield, biotic and abiotic stress tolerance have been cultivated for decades. Thus far, a major challenge with hybrid seeds is that they do not have the ability to produce plants with the same qualities over subsequent generations. Apomixis, an asexual mode of reproduction by avoiding meiosis, exists naturally in flowering plants, and ultimately leads to seed production. Apomixis has the potential to preserve hybrid vigor for multiple generations in economically important plant genotypes. The evolution and genetics of asexual seed production are unclear, and much more effort will be required to determine the genetic architecture of this phenomenon. To fix hybrid vigor, synthetic apomixis has been suggested. The development of MiMe (mitosis instead of meiosis) genotypes has been utilized for clonal gamete production. However, the identification and parental origin of genes responsible for synthetic apomixis are little known and need further clarification. Genome modifications utilizing genome editing technologies (GETs), such as clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (cas), a reverse genetics tool, have paved the way toward the utilization of emerging technologies in plant molecular biology. Over the last decade, several genes in important crops have been successfully edited. The vast availability of GETs has made functional genomics studies easy to conduct in crops important for food security. Disruption in the expression of genes specific to egg cell MATRILINEAL (MTL) through the CRISPR/Cas genome editing system promotes the induction of haploid seed, whereas triple knockout of the Baby Boom (BBM) genes BBM1, BBM2, and BBM3 cause embryo arrest and abortion, which can be fully rescued by male-transmitted BBM1. The establishment of synthetic apomixis by engineering the MiMe genotype by genome editing of BBM1 expression or disruption of MTL leads to clonal seed production and heritability for multiple generations. In the present review, we discuss current developments related to the use of CRISPR/Cas technology in plants and the possibility of promoting apomixis in crops to preserve hybrid vigor. In addition, genetics, evolution, epigenetic modifications, and strategies for MiMe genotype development are discussed in detail.
Collapse
Affiliation(s)
- Sajid Fiaz
- Department of Plant Breeding and Genetics, The University of Haripur 22620 , Khyber Pakhtunkhwa, Pakistan
| | - Xiukang Wang
- College of Life Sciences, Yan'an University , Yan'an, Shaanxi, China
| | - Afifa Younas
- Department of Botany, Lahore College for Women University , Lahore, Pakistan
| | - Badr Alharthi
- College of Science and Engineering, Flinders University , Adelaide, Australia
- University College of Khurma, Taif University , Taif, Saudi Arabia
| | - Adeel Riaz
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences , Beijing, China
| | - Habib Ali
- Department of Agricultural Engineering, Khawaja Fareed University of Engineering and Information Technology , Rahim Yar Khan, Pakistan
- Department of Entomology, Sub-Campus Depalpur, University of Agriculture Faisalabad , Faisalabad, Pakistan
| |
Collapse
|
30
|
De Kort H, Panis B, Deforce D, Van Nieuwerburgh F, Honnay O. Ecological divergence of wild strawberry DNA methylation patterns at distinct spatial scales. Mol Ecol 2020; 29:4871-4881. [DOI: 10.1111/mec.15689] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 10/01/2020] [Accepted: 10/02/2020] [Indexed: 12/16/2022]
Affiliation(s)
- Hanne De Kort
- Plant Conservation and Population Biology University of Leuven Leuven Belgium
| | - Bart Panis
- Bioversity InternationalK.U. Leuven Leuven Belgium
| | - Dieter Deforce
- Laboratory of Pharmaceutical Biotechnology Ghent University Ghent Belgium
| | | | - Ollivier Honnay
- Plant Conservation and Population Biology University of Leuven Leuven Belgium
| |
Collapse
|
31
|
Epigenetics and epigenomics: underlying mechanisms, relevance, and implications in crop improvement. Funct Integr Genomics 2020; 20:739-761. [PMID: 33089419 DOI: 10.1007/s10142-020-00756-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 10/12/2020] [Accepted: 10/14/2020] [Indexed: 01/21/2023]
Abstract
Epigenetics is defined as changes in gene expression that are not associated with changes in DNA sequence but due to the result of methylation of DNA and post-translational modifications to the histones. These epigenetic modifications are known to regulate gene expression by bringing changes in the chromatin state, which underlies plant development and shapes phenotypic plasticity in responses to the environment and internal cues. This review articulates the role of histone modifications and DNA methylation in modulating biotic and abiotic stresses, as well as crop improvement. It also highlights the possibility of engineering epigenomes and epigenome-based predictive models for improving agronomic traits.
Collapse
|
32
|
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.
Collapse
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.
| |
Collapse
|
33
|
Pecinka A, Chevalier C, Colas I, Kalantidis K, Varotto S, Krugman T, Michailidis C, Vallés MP, Muñoz A, Pradillo M. Chromatin dynamics during interphase and cell division: similarities and differences between model and crop plants. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:5205-5222. [PMID: 31626285 DOI: 10.1093/jxb/erz457] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 09/30/2019] [Indexed: 06/10/2023]
Abstract
Genetic information in the cell nucleus controls organismal development and responses to the environment, and finally ensures its own transmission to the next generations. To achieve so many different tasks, the genetic information is associated with structural and regulatory proteins, which orchestrate nuclear functions in time and space. Furthermore, plant life strategies require chromatin plasticity to allow a rapid adaptation to abiotic and biotic stresses. Here, we summarize current knowledge on the organization of plant chromatin and dynamics of chromosomes during interphase and mitotic and meiotic cell divisions for model and crop plants differing as to genome size, ploidy, and amount of genomic resources available. The existing data indicate that chromatin changes accompany most (if not all) cellular processes and that there are both shared and unique themes in the chromatin structure and global chromosome dynamics among species. Ongoing efforts to understand the molecular mechanisms involved in chromatin organization and remodeling have, together with the latest genome editing tools, potential to unlock crop genomes for innovative breeding strategies and improvements of various traits.
Collapse
Affiliation(s)
- Ales Pecinka
- Institute of Experimental Botany, Czech Acad Sci, Centre of the Region Haná for Agricultural and Biotechnological Research, Olomouc, Czech Republic
| | | | - Isabelle Colas
- James Hutton Institute, Cell and Molecular Science, Pr Waugh's Lab, Invergowrie, Dundee, UK
| | - Kriton Kalantidis
- Department of Biology, University of Crete, and Institute of Molecular Biology Biotechnology, FoRTH, Heraklion, Greece
| | - Serena Varotto
- Department of Agronomy Animal Food Natural Resources and Environment (DAFNAE) University of Padova, Agripolis viale dell'Università, Legnaro (PD), Italy
| | - Tamar Krugman
- Institute of Evolution, University of Haifa, Haifa, Israel
| | - Christos Michailidis
- Institute of Experimental Botany, Czech Acad Sci, Praha 6 - Lysolaje, Czech Republic
| | - María-Pilar Vallés
- Department of Genetics and Plant Breeding, Estación Experimental Aula Dei (EEAD), Spanish National Research Council (CSIC), Zaragoza, Spain
| | - Aitor Muñoz
- Department of Plant Molecular Genetics, National Center of Biotechnology/Superior Council of Scientific Research, Autónoma University of Madrid, Madrid, Spain
| | - Mónica Pradillo
- Department of Genetics, Physiology and Microbiology, Faculty of Biology, Complutense University of Madrid, Madrid, Spain
| |
Collapse
|
34
|
Sinha P, Singh VK, Saxena RK, Kale SM, Li Y, Garg V, Meifang T, Khan AW, Kim KD, Chitikineni A, Saxena KB, Sameer Kumar CV, Liu X, Xu X, Jackson S, Powell W, Nevo E, Searle IR, Lodha M, Varshney RK. Genome-wide analysis of epigenetic and transcriptional changes associated with heterosis in pigeonpea. PLANT BIOTECHNOLOGY JOURNAL 2020; 18:1697-1710. [PMID: 31925873 PMCID: PMC7336283 DOI: 10.1111/pbi.13333] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Accepted: 12/26/2019] [Indexed: 05/20/2023]
Abstract
Hybrids are extensively used in agriculture to deliver an increase in yield, yet the molecular basis of heterosis is not well understood. Global DNA methylation analysis, transcriptome analysis and small RNA profiling were aimed to understand the epigenetic effect of the changes in gene expression level in the two hybrids and their parental lines. Increased DNA methylation was observed in both the hybrids as compared to their parents. This increased DNA methylation in hybrids showed that majority of the 24-nt siRNA clusters had higher expression in hybrids than the parents. Transcriptome analysis revealed that various phytohormones (auxin and salicylic acid) responsive hybrid-MPV DEGs were significantly altered in both the hybrids in comparison to MPV. DEGs associated with plant immunity and growth were overexpressed whereas DEGs associated with basal defence level were repressed. This antagonistic patterns of gene expression might contribute to the greater growth of the hybrids. It was also noticed that some common as well as unique changes in the regulatory pathways were associated with heterotic growth in both the hybrids. Approximately 70% and 67% of down-regulated hybrid-MPV DEGs were found to be differentially methylated in ICPH 2671 and ICPH 2740 hybrid, respectively. This reflected the association of epigenetic regulation in altered gene expressions. Our findings also revealed that miRNAs might play important roles in hybrid vigour in both the hybrids by regulating their target genes, especially in controlling plant growth and development, defence and stress response pathways. The above finding provides an insight into the molecular mechanism of pigeonpea heterosis.
Collapse
Affiliation(s)
- Pallavi Sinha
- International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT)PatancheruIndia
| | - Vikas K. Singh
- International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT)PatancheruIndia
- International Rice Research Institute, South‐Asia HubPatancheruIndia
| | - Rachit K. Saxena
- International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT)PatancheruIndia
| | - Sandip M. Kale
- International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT)PatancheruIndia
- The Leibniz Institute of Plant Genetics and Crop Plant ResearchGaterslebenGermany
| | | | - Vanika Garg
- International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT)PatancheruIndia
| | | | - Aamir W. Khan
- International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT)PatancheruIndia
| | - Kyung Do Kim
- University of GeorgiaAthensUSA
- Myongji UniversityYonginRepublic of Korea
| | - Annapurna Chitikineni
- International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT)PatancheruIndia
| | - K. B. Saxena
- International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT)PatancheruIndia
| | - C. V. Sameer Kumar
- International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT)PatancheruIndia
| | | | - Xun Xu
- BGI‐ShenzhenShenzhenChina
| | | | | | | | | | - Mukesh Lodha
- Centre for Cellular and Molecular Biology (CSIR)HyderabadIndia
| | - Rajeev K. Varshney
- International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT)PatancheruIndia
| |
Collapse
|
35
|
Heterosis Breeding in Eggplant ( Solanum melongena L.): Gains and Provocations. PLANTS 2020; 9:plants9030403. [PMID: 32213925 PMCID: PMC7154857 DOI: 10.3390/plants9030403] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/17/2020] [Accepted: 03/20/2020] [Indexed: 01/15/2023]
Abstract
Heterosis (or hybrid vigor) results in a hybrid’s phenotypic superiority over its founder parents for quantitative and qualitative traits. Hybrid vigor is defined by mechanisms such as dominant complementation, over-dominance, and epistasis. Eggplant (Solanum melongena L.) is an essential vegetable crop and a good source of dietary minerals, vitamins, and anthocyanins, with a high oxygen radical absorbance capacity and low caloric value. Given the economic and nutritional significance of eggplants, breeding efforts focus on developing high-yielding varieties—mostly F1 hybrids—with important traits. Studies indicate the successful exploitation of heterosis in the eggplant for a considerable improvement with respect to quantitative traits. In this direction, estimating heterosis for yield-related traits could well be useful for examining the most beneficial hybrid mix with the exploitation of top-quality hybrid. This review examines the current perception of the breeding and molecular aspects of heterosis in eggplants and cites several studies describing the mechanisms. Rendering and combining recent genomics, epigenetic, proteomic, and metabolomics studies present new prospects towards the understanding of the regulatory events of heterosis involved in the evolution and the domestication of the eggplant ideotype.
Collapse
|
36
|
McKeown P, Spillane C. An Overview of Current Research in Plant Epigenetic and Epigenomic Phenomena. Methods Mol Biol 2020; 2093:3-13. [PMID: 32088885 DOI: 10.1007/978-1-0716-0179-2_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Biological phenomena defined as having an "epigenetic" component (according to various definitions) have been extensively studied in plant systems and illuminated many mechanisms by which gene expression is regulated and patterns of expression inherited through cell divisions. This second volume of Plant Epigenetics and Epigenomics: Methods in Molecular Biology builds on the work of its predecessor to describe cutting-edge tools for plant epigenetic and epigenomic research, and embrace crop and forestry species as well as natural populations and further insights from model species. In this chapter, the historical background to plant epigenetic and epigenomic research is summarized, and key considerations for the interpretation of current data are outlined.
Collapse
Affiliation(s)
- Peter McKeown
- Plant and Agribiosciences Research Centre, Ryan Institute, National University of Ireland Galway (NUI Galway), Galway, Ireland.
| | - Charles Spillane
- Plant and Agribiosciences Research Centre, Ryan Institute, National University of Ireland Galway (NUI Galway), Galway, Ireland
| |
Collapse
|
37
|
Liu H, Wang Q, Chen M, Ding Y, Yang X, Liu J, Li X, Zhou C, Tian Q, Lu Y, Fan D, Shi J, Zhang L, Kang C, Sun M, Li F, Wu Y, Zhang Y, Liu B, Zhao XY, Feng Q, Yang J, Han B, Lai J, Zhang XS, Huang X. Genome-wide identification and analysis of heterotic loci in three maize hybrids. PLANT BIOTECHNOLOGY JOURNAL 2020; 18:185-194. [PMID: 31199059 PMCID: PMC6920156 DOI: 10.1111/pbi.13186] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 06/01/2019] [Accepted: 06/04/2019] [Indexed: 05/18/2023]
Abstract
Heterosis, or hybrid vigour, is a predominant phenomenon in plant genetics, serving as the basis of crop hybrid breeding, but the causative loci and genes underlying heterosis remain unclear in many crops. Here, we present a large-scale genetic analysis using 5360 offsprings from three elite maize hybrids, which identifies 628 loci underlying 19 yield-related traits with relatively high mapping resolutions. Heterotic pattern investigations of the 628 loci show that numerous loci, mostly with complete-incomplete dominance (the major one) or overdominance effects (the secondary one) for heterozygous genotypes and nearly equal proportion of advantageous alleles from both parental lines, are the major causes of strong heterosis in these hybrids. Follow-up studies for 17 heterotic loci in an independent experiment using 2225 F2 individuals suggest most heterotic effects are roughly stable between environments with a small variation. Candidate gene analysis for one major heterotic locus (ub3) in maize implies that there may exist some common genes contributing to crop heterosis. These results provide a community resource for genetics studies in maize and new implications for heterosis in plants.
Collapse
Affiliation(s)
- Hongjun Liu
- State Key Laboratory of Crop BiologyCollege of Life SciencesShandong Agricultural UniversityTai'anChina
| | - Qin Wang
- Shanghai Key Laboratory of Plant Molecular SciencesCollege of Life SciencesShanghai Normal UniversityShanghaiChina
| | - Mengjiao Chen
- Shanghai Key Laboratory of Plant Molecular SciencesCollege of Life SciencesShanghai Normal UniversityShanghaiChina
| | - Yahui Ding
- State Key Laboratory of Crop BiologyCollege of Life SciencesShandong Agricultural UniversityTai'anChina
| | - Xuerong Yang
- State Key Laboratory of Crop BiologyCollege of Life SciencesShandong Agricultural UniversityTai'anChina
| | - Jie Liu
- Shanghai Key Laboratory of Plant Molecular SciencesCollege of Life SciencesShanghai Normal UniversityShanghaiChina
| | - Xiaohan Li
- State Key Laboratory of Crop BiologyCollege of Life SciencesShandong Agricultural UniversityTai'anChina
| | - Congcong Zhou
- National Center for Gene ResearchCAS Center for Excellence of Molecular Plant SciencesInstitute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghaiChina
| | - Qilin Tian
- National Center for Gene ResearchCAS Center for Excellence of Molecular Plant SciencesInstitute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghaiChina
| | - Yiqi Lu
- National Center for Gene ResearchCAS Center for Excellence of Molecular Plant SciencesInstitute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghaiChina
| | - Danlin Fan
- National Center for Gene ResearchCAS Center for Excellence of Molecular Plant SciencesInstitute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghaiChina
| | - Junpeng Shi
- State Key Laboratory of Agrobiotechnology and National Maize Improvement CenterDepartment of Plant Genetics and BreedingChina Agricultural UniversityBeijingChina
| | - Lin Zhang
- College of AgricultureNortheast Agricultural UniversityHarbinChina
| | - Congbin Kang
- State Key Laboratory of Crop BiologyCollege of Life SciencesShandong Agricultural UniversityTai'anChina
| | - Mingfei Sun
- State Key Laboratory of Crop BiologyCollege of Life SciencesShandong Agricultural UniversityTai'anChina
| | - Fangyuan Li
- State Key Laboratory of Crop BiologyCollege of Life SciencesShandong Agricultural UniversityTai'anChina
| | - Yujian Wu
- State Key Laboratory of Crop BiologyCollege of Life SciencesShandong Agricultural UniversityTai'anChina
| | - Yongzhong Zhang
- State Key Laboratory of Crop BiologyCollege of AgronomyShandong Agricultural UniversityTai'anChina
| | - Baoshen Liu
- State Key Laboratory of Crop BiologyCollege of AgronomyShandong Agricultural UniversityTai'anChina
| | - Xiang Yu Zhao
- State Key Laboratory of Crop BiologyCollege of Life SciencesShandong Agricultural UniversityTai'anChina
| | - Qi Feng
- National Center for Gene ResearchCAS Center for Excellence of Molecular Plant SciencesInstitute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghaiChina
| | - Jinliang Yang
- Department of Agronomy and HorticultureUniversity of Nebraska‐LincolnLincolnNEUSA
| | - Bin Han
- National Center for Gene ResearchCAS Center for Excellence of Molecular Plant SciencesInstitute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghaiChina
| | - Jinsheng Lai
- State Key Laboratory of Agrobiotechnology and National Maize Improvement CenterDepartment of Plant Genetics and BreedingChina Agricultural UniversityBeijingChina
| | - Xian Sheng Zhang
- State Key Laboratory of Crop BiologyCollege of Life SciencesShandong Agricultural UniversityTai'anChina
| | - Xuehui Huang
- Shanghai Key Laboratory of Plant Molecular SciencesCollege of Life SciencesShanghai Normal UniversityShanghaiChina
| |
Collapse
|
38
|
Wang K. Fixation of hybrid vigor in rice: synthetic apomixis generated by genome editing. ABIOTECH 2020; 1:15-20. [PMID: 36305008 PMCID: PMC9584092 DOI: 10.1007/s42994-019-00001-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 06/18/2019] [Indexed: 11/28/2022]
Abstract
Apomixis is an asexual reproduction process in which clonal seeds are formed without meiosis and fertilization. Because of its potential in permanently preserving hybrid vigor, apomixis has attracted a great deal of interests from plant biologists and the seed industry. However, despite of decades of effort, introgression of apomixis traits from wild relatives into major crops has remained unsuccessful. Therefore, synthetic apomixis has been proposed as an alternative to fix hybrid vigor. In this article, I present the development of the MiMe (Mitosis instead of Meiosis), which turns meiosis into mitosis and leads to the production of clonal gametes. Apomixis-like clonal seeds are generated when MiMe plants are crossed to special genome elimination lines, which contain an altered centromere-specific histone 3 (CENH3). Furthermore, induction of haploid plants from egg cells can be achieved by either egg cell-specific expression of BABY BOOM1 (BBM1), or disruption of MATRILINEAL (MTL) using CRISPR/Cas9 gene-editing technology. Synthetic apomixis is established and clonal seeds are produced by simultaneous engineering MiMe with altering BBM1 expression or MTL disruption. Finally, I discuss how to further improve the apomixis strategy and its applications in crop breeding.
Collapse
Affiliation(s)
- Kejian Wang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310006 China
| |
Collapse
|
39
|
Ben Maamar M, King SE, Nilsson E, Beck D, Skinner MK. Epigenetic transgenerational inheritance of parent-of-origin allelic transmission of outcross pathology and sperm epimutations. Dev Biol 2019; 458:106-119. [PMID: 31682807 PMCID: PMC6987017 DOI: 10.1016/j.ydbio.2019.10.030] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/25/2019] [Accepted: 10/29/2019] [Indexed: 12/11/2022]
Abstract
Epigenetic transgenerational inheritance potentially impacts disease etiology, phenotypic variation, and evolution. An increasing number of environmental factors from nutrition to toxicants have been shown to promote the epigenetic transgenerational inheritance of disease. Previous observations have demonstrated that the agricultural fungicide vinclozolin and pesticide DDT (dichlorodiphenyltrichloroethane) induce transgenerational sperm epimutations involving DNA methylation, ncRNA, and histone modifications or retention. These two environmental toxicants were used to investigate the impacts of parent-of-origin outcross on the epigenetic transgenerational inheritance of disease. Male and female rats were collected from a paternal outcross (POC) or a maternal outcross (MOC) F4 generation control and exposure lineages for pathology and epigenetic analysis. This model allows the parental allelic transmission of disease and epimutations to be investigated. There was increased pathology incidence in the MOC F4 generation male prostate, kidney, obesity, and multiple diseases through a maternal allelic transmission. The POC F4 generation female offspring had increased pathology incidence for kidney, obesity and multiple types of diseases through the paternal allelic transmission. Some disease such as testis or ovarian pathology appear to be transmitted through the combined actions of both male and female alleles. Analysis of the F4 generation sperm epigenomes identified differential DNA methylated regions (DMRs) in a genome-wide analysis. Observations demonstrate that DDT and vinclozolin have the potential to promote the epigenetic transgenerational inheritance of disease and sperm epimutations to the outcross F4 generation in a sex specific and exposure specific manner. The parent-of-origin allelic transmission observed appears similar to the process involved with imprinted-like genes.
Collapse
Affiliation(s)
- Millissia Ben Maamar
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA, 99164-4236, USA
| | - Stephanie E King
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA, 99164-4236, USA
| | - Eric Nilsson
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA, 99164-4236, USA
| | - Daniel Beck
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA, 99164-4236, USA
| | - Michael K Skinner
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA, 99164-4236, USA.
| |
Collapse
|
40
|
Abstract
DNA methylation is a conserved epigenetic modification that is important for gene regulation and genome stability. Aberrant patterns of DNA methylation can lead to plant developmental abnormalities. A specific DNA methylation state is an outcome of dynamic regulation by de novo methylation, maintenance of methylation and active demethylation, which are catalysed by various enzymes that are targeted by distinct regulatory pathways. In this Review, we discuss DNA methylation in plants, including methylating and demethylating enzymes and regulatory factors, and the coordination of methylation and demethylation activities by a so-called methylstat mechanism; the functions of DNA methylation in regulating transposon silencing, gene expression and chromosome interactions; the roles of DNA methylation in plant development; and the involvement of DNA methylation in plant responses to biotic and abiotic stress conditions.
Collapse
|
41
|
Paun O, Verhoeven KJ, Richards CL. Opportunities and limitations of reduced representation bisulfite sequencing in plant ecological epigenomics. THE NEW PHYTOLOGIST 2019; 221:738-742. [PMID: 30121954 PMCID: PMC6504643 DOI: 10.1111/nph.15388] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Accepted: 07/03/2018] [Indexed: 05/13/2023]
Abstract
Contents Summary 738 I. Introduction 738 II. RRBS loci as genome-wide epigenetic markers 739 III. Exploiting functional annotation of RRBS loci 739 IV. Limitations of RRBS methods for nonmodel species 740 V. Maximising the impact of RRBS in plants 741 VI. Conclusions 741 Acknowledgements 741 SUMMARY: Investigating the features and implications of epigenetic mechanisms across the breadth of organisms and ecosystems is important for understanding the ecological relevance of epigenetics. Several cost-effective reduced representation bisulfite sequencing approaches (RRBS) have been recently developed and applied to different organisms that lack a well annotated reference genome. These new approaches improve the assessment of epigenetic diversity in ecological settings and may provide functional insights. We assess here the opportunities and limitations of RRBS in nonmodel plant species. Well thought out experimental designs that include complementary gene expression studies, and the improvement of genomics resources for the target group, promise to maximize the effect of future RRBS studies.
Collapse
Affiliation(s)
- Ovidiu Paun
- Department for Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria
| | | | - Christina L. Richards
- Department of Integrative Biology, University of South Florida, Tampa, FL 33620, USA
| |
Collapse
|
42
|
Diurnal down-regulation of ethylene biosynthesis mediates biomass heterosis. Proc Natl Acad Sci U S A 2018; 115:5606-5611. [PMID: 29735680 DOI: 10.1073/pnas.1722068115] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Heterosis is widely applied in agriculture; however, the underlying molecular mechanisms for superior performance are not well understood. Ethylene biosynthesis and signaling genes are shown to be down-regulated in Arabidopsis interspecific hybrids. Ethylene is a plant hormone that promotes fruit ripening and maturation but inhibits hypocotyl elongation. Here we report that application of exogenous ethylene could eliminate biomass vigor in Arabidopsis thaliana F1 hybrids, suggesting a negative role of ethylene in heterosis. Ethylene biosynthesis is mediated by the rate-limiting enzyme, 1-aminocyclopropane-1-carboxylate synthase (ACS). Down-regulation of ACS genes led to the decrease of ethylene production, which was associated with the high-vigor F1 hybrids, but not with the low-vigor ones. At the mechanistic level, expression of ACS genes was down-regulated diurnally and indirectly by Circadian Clock Associated 1 (CCA1) during the day and directly by Phyotochrome-Interacting Factor 5 (PIF5) at night. Consistent with the negative role of ethylene in plant growth, biomass vigor was higher in the acs mutants than in wild-type plants, while increasing endogenous ethylene production in the hybridizing parents reduced growth vigor in the hybrids. Thus, integrating circadian rhythms and light signaling into ethylene production is another regulatory module of complex biological networks, leading to biomass heterosis in plants.
Collapse
|
43
|
Seifert F, Thiemann A, Grant-Downton R, Edelmann S, Rybka D, Schrag TA, Frisch M, Dickinson HG, Melchinger AE, Scholten S. Parental Expression Variation of Small RNAs Is Negatively Correlated with Grain Yield Heterosis in a Maize Breeding Population. FRONTIERS IN PLANT SCIENCE 2018; 9:13. [PMID: 29441076 PMCID: PMC5797689 DOI: 10.3389/fpls.2018.00013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 01/04/2018] [Indexed: 05/26/2023]
Abstract
Heterosis refers to a quantitative phenomenon in which F1 hybrid trait values exceed the mean of the parental values in a positive direction. Generally, it is dependent on a high degree of heterozygosity, which is maintained in hybrid breeding by developing parental lines in separate, genetically distinct heterotic groups. The mobility of small RNAs (sRNAs) that mediate epigenetic regulation of gene expression renders them promising candidates for modulating the action of combined diverse genomes in trans-and evidence already indicates their contribution to transgressive phenotypes. By sequencing small RNA libraries of a panel of 21 maize parental inbred lines we found a low overlap of 35% between the sRNA populations from both distinct heterotic groups. Surprisingly, in contrast to genetic or gene expression variation, parental sRNA expression variation is negatively correlated with grain yield (GY) heterosis. Among 0.595 million expressed sRNAs, we identified 9,767, predominantly 22- and 24-nt long sRNAs, which showed an association of their differential expression between parental lines and GY heterosis of the respective hybrids. Of these sRNAs, 3,485 or 6,282 showed an association with high or low GY heterosis, respectively, thus the low heterosis associated group prevailing at 64%. The heterosis associated sRNAs map more frequently to genes that show differential expression between parental lines than reference sets. Together these findings suggest that trans-chromosomal actions of sRNAs in hybrids might add up to a negative contribution in heterosis formation, mediated by unfavorable gene expression regulation. We further revealed an exclusive accumulation of 22-nt sRNAs that are associated with low GY heterosis in pericentromeric genomic regions. That recombinational suppression led to this enrichment is indicated by its close correlation with low recombination rates. The existence of this enrichment, which we hypothesize resulted from the separated breeding of inbred lines within heterotic groups, may have implications for hybrid breeding strategies addressing the recombinational constraints characteristic of complex crop genomes.
Collapse
Affiliation(s)
- Felix Seifert
- Biocenter Klein Flottbek, University of Hamburg, Hamburg, Germany
| | | | | | - Susanne Edelmann
- Biocenter Klein Flottbek, University of Hamburg, Hamburg, Germany
| | - Dominika Rybka
- Biocenter Klein Flottbek, University of Hamburg, Hamburg, Germany
| | - Tobias A. Schrag
- Institute for Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, Stuttgart, Germany
| | - Matthias Frisch
- Institute of Agronomy and Plant Breeding II, Justus-Liebig University, Giessen, Germany
| | - Hugh G. Dickinson
- Department of Plant Sciences, University of Oxford, Oxford, United Kingdom
| | - Albrecht E. Melchinger
- Institute for Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, Stuttgart, Germany
| | - Stefan Scholten
- Biocenter Klein Flottbek, University of Hamburg, Hamburg, Germany
- Institute for Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, Stuttgart, Germany
| |
Collapse
|
44
|
Itabashi E, Osabe K, Fujimoto R, Kakizaki T. Epigenetic regulation of agronomical traits in Brassicaceae. PLANT CELL REPORTS 2018; 37:87-101. [PMID: 29058037 DOI: 10.1007/s00299-017-2223-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/05/2017] [Indexed: 05/08/2023]
Abstract
Epigenetic regulation, covalent modification of DNA and changes in histone proteins are closely linked to plant development and stress response through flexibly altering the chromatin structure to regulate gene expression. In this review, we will illustrate the importance of epigenetic influences by discussing three agriculturally important traits of Brassicaceae. (1) Vernalization, an acceleration of flowering by prolonged cold exposure regulated through epigenetic silencing of a central floral repressor, FLOWERING LOCUS C. This is associated with cold-dependent repressive histone mark accumulation, which confers competency of consequence vegetative-to-reproductive phase transition. (2) Hybrid vigor, in which an F1 hybrid shows superior performance to the parental lines. Combination of distinct epigenomes with different DNA methylation states between parental lines is important for increase in growth rate in a hybrid progeny. This is independent of siRNA-directed DNA methylation but dependent on the chromatin remodeler DDM1. (3) Self-incompatibility, a reproductive mating system to prevent self-fertilization. This is controlled by the S-locus consisting of SP11 and SRK which are responsible for self/non-self recognition. Because self-incompatibility in Brassicaceae is sporophytically controlled, there are dominance relationships between S haplotypes in the stigma and pollen. The dominance relationships in the pollen rely on de novo DNA methylation at the promoter region of a recessive allele, which is triggered by siRNA production from a flanking region of a dominant allele.
Collapse
Affiliation(s)
- Etsuko Itabashi
- Institute of Vegetable and Floriculture Science, NARO, Kusawa, Ano, Tsu, Mie, 514-2392, Japan.
| | - Kenji Osabe
- Okinawa Institute of Science and Technology Graduate University, Onna-son, Kunigami, Okinawa, 904-0495, Japan
| | - Ryo Fujimoto
- Graduate School of Agricultural Science, Kobe University, Rokkodai, Nada-ku, Kobe, 657-8501, Japan
| | - Tomohiro Kakizaki
- Institute of Vegetable and Floriculture Science, NARO, Kusawa, Ano, Tsu, Mie, 514-2392, Japan
| |
Collapse
|
45
|
Abstract
While DNA sequence variation is known to be a major driver of phenotypic divergence, epigenetic variation has long been disregarded. One reason for that was the lack of suitable tools. The creation of epigenetically divergent but otherwise largely isogenic Arabidopsis populations has now alleviated some of these constraints. Epigenetic recombinant inbred line (epiRIL) populations allow for examining the effects of epigenetic variation on phenotypes. In addition, epiRILs enabled the development of epigenetic quantitative trait locus (QTLepi) mapping, an approach to identify causal epigenetic factors. Here, we describe the successive steps of QTLepi mapping in a broad sense, from the creation of epigenetically divergent populations to the identification of causal genes underlying particular phenotypes in Arabidopsis.
Collapse
Affiliation(s)
- Kathrin Lauss
- Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098XH, Amsterdam, The Netherlands
| | - Joost J B Keurentjes
- Laboratory of Genetics, Wageningen University and Research, Droevendaalsesteeg 1, 6708PB, Wageningen, The Netherlands.
| |
Collapse
|
46
|
Dwivedi SL, Scheben A, Edwards D, Spillane C, Ortiz R. Assessing and Exploiting Functional Diversity in Germplasm Pools to Enhance Abiotic Stress Adaptation and Yield in Cereals and Food Legumes. FRONTIERS IN PLANT SCIENCE 2017; 8:1461. [PMID: 28900432 PMCID: PMC5581882 DOI: 10.3389/fpls.2017.01461] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 08/07/2017] [Indexed: 05/03/2023]
Abstract
There is a need to accelerate crop improvement by introducing alleles conferring host plant resistance, abiotic stress adaptation, and high yield potential. Elite cultivars, landraces and wild relatives harbor useful genetic variation that needs to be more easily utilized in plant breeding. We review genome-wide approaches for assessing and identifying alleles associated with desirable agronomic traits in diverse germplasm pools of cereals and legumes. Major quantitative trait loci and single nucleotide polymorphisms (SNPs) associated with desirable agronomic traits have been deployed to enhance crop productivity and resilience. These include alleles associated with variation conferring enhanced photoperiod and flowering traits. Genetic variants in the florigen pathway can provide both environmental flexibility and improved yields. SNPs associated with length of growing season and tolerance to abiotic stresses (precipitation, high temperature) are valuable resources for accelerating breeding for drought-prone environments. Both genomic selection and genome editing can also harness allelic diversity and increase productivity by improving multiple traits, including phenology, plant architecture, yield potential and adaptation to abiotic stresses. Discovering rare alleles and useful haplotypes also provides opportunities to enhance abiotic stress adaptation, while epigenetic variation has potential to enhance abiotic stress adaptation and productivity in crops. By reviewing current knowledge on specific traits and their genetic basis, we highlight recent developments in the understanding of crop functional diversity and identify potential candidate genes for future use. The storage and integration of genetic, genomic and phenotypic information will play an important role in ensuring broad and rapid application of novel genetic discoveries by the plant breeding community. Exploiting alleles for yield-related traits would allow improvement of selection efficiency and overall genetic gain of multigenic traits. An integrated approach involving multiple stakeholders specializing in management and utilization of genetic resources, crop breeding, molecular biology and genomics, agronomy, stress tolerance, and reproductive/seed biology will help to address the global challenge of ensuring food security in the face of growing resource demands and climate change induced stresses.
Collapse
Affiliation(s)
| | - Armin Scheben
- School of Biological Sciences, Institute of Agriculture, University of Western Australia, PerthWA, Australia
| | - David Edwards
- School of Biological Sciences, Institute of Agriculture, University of Western Australia, PerthWA, Australia
| | - Charles Spillane
- Plant and AgriBiosciences Research Centre, Ryan Institute, National University of Ireland GalwayGalway, Ireland
| | - Rodomiro Ortiz
- Department of Plant Breeding, Swedish University of Agricultural SciencesAlnarp, Sweden
| |
Collapse
|
47
|
Hofmeister BT, Lee K, Rohr NA, Hall DW, Schmitz RJ. Stable inheritance of DNA methylation allows creation of epigenotype maps and the study of epiallele inheritance patterns in the absence of genetic variation. Genome Biol 2017; 18:155. [PMID: 28814343 PMCID: PMC5559844 DOI: 10.1186/s13059-017-1288-x] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 07/27/2017] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Differences in DNA methylation can arise as epialleles, which are loci that differ in chromatin state and are inherited over generations. Epialleles offer an additional source of variation that can affect phenotypic diversity beyond changes to nucleotide sequence. Previous research has looked at the rate at which spontaneous epialleles arise but it is currently unknown how they are maintained across generations. RESULTS We used two Arabidopsis thaliana mutation accumulation (MA) lines and determined that over 99.998% of the methylated regions in the genome are stably inherited across each generation indicating that spontaneous epialleles are rare. We also developed a novel procedure that determines genotypes for offspring of genetically identical parents using only DNA methylation data. The resulting epigenotype maps are highly accurate and strongly agree with expected allele frequency and crossover number. Using epigenotype maps, we explore the inheritance of methylation states in regions of differential methylation between the parents of genetic crosses. Over half of the regions show methylation levels consistent with cis inheritance, whereas the other half show evidence of trans-chromosomal methylation and demethylation as well as other possibilities. CONCLUSIONS DNA methylation is stably inherited by offspring and spontaneous epialleles are rare. The epigenotyping procedure that we describe provides an important first step to epigenetic quantitative trait loci mapping in genetically identical individuals.
Collapse
Affiliation(s)
| | - Kevin Lee
- Department of Genetics, University of Georgia, Athens, GA, 30602, USA
| | - Nicholas A Rohr
- Department of Genetics, University of Georgia, Athens, GA, 30602, USA
| | - David W Hall
- Department of Genetics, University of Georgia, Athens, GA, 30602, USA
| | - Robert J Schmitz
- Department of Genetics, University of Georgia, Athens, GA, 30602, USA.
| |
Collapse
|
48
|
|
49
|
Abstract
Despite major progress in dissecting the molecular pathways that control DNA methylation patterns in plants, little is known about the mechanisms that shape plant methylomes over evolutionary time. Drawing on recent intra- and interspecific epigenomic studies, we show that methylome evolution over long timescales is largely a byproduct of genomic changes. By contrast, methylome evolution over short timescales appears to be driven mainly by spontaneous epimutational events. We argue that novel methods based on analyses of the methylation site frequency spectrum (mSFS) of natural populations can provide deeper insights into the evolutionary forces that act at each timescale.
Collapse
Affiliation(s)
- Amaryllis Vidalis
- Population Epigenetics and Epigenomics, Technical University of Munich, Liesel-Beckman-Str. 2, 85354, Freising, Germany
| | - Daniel Živković
- Population Genetics, Technical University of Munich, Liesel-Beckman-Str. 2, 85354, Freising, Germany
| | - René Wardenaar
- Groningen Bioinformatics Centre, University of Groningen, 9747 AG, Groningen, The Netherlands
| | - David Roquis
- Population Epigenetics and Epigenomics, Technical University of Munich, Liesel-Beckman-Str. 2, 85354, Freising, Germany
| | - Aurélien Tellier
- Population Genetics, Technical University of Munich, Liesel-Beckman-Str. 2, 85354, Freising, Germany.
| | - Frank Johannes
- Population Epigenetics and Epigenomics, Technical University of Munich, Liesel-Beckman-Str. 2, 85354, Freising, Germany. .,Institute for Advanced Study, Technical University of Munich, Lichtenbergstr. 2a, 85748, Garching, Germany.
| |
Collapse
|
50
|
Twenty-four-nucleotide siRNAs produce heritable trans-chromosomal methylation in F1 Arabidopsis hybrids. Proc Natl Acad Sci U S A 2016; 113:E6895-E6902. [PMID: 27791153 DOI: 10.1073/pnas.1613623113] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Hybrid Arabidopsis plants undergo epigenetic reprogramming producing decreased levels of 24-nt siRNAs and altered patterns of DNA methylation that can affect gene expression. Driving the changes in methylation are the processes trans-chromosomal methylation (TCM) and trans-chromosomal demethylation (TCdM). In TCM/TCdM the methylation state of one allele is altered to resemble the other allele. We show that Pol IV-dependent sRNAs are required to establish TCM events. The changes in DNA methylation and the associated changes in sRNA levels in the F1 hybrid can be maintained in subsequent generations and affect hundreds of regions in the F2 epigenome. The inheritance of these altered epigenetic states varies in F2 individuals, resulting in individuals with genetically identical loci displaying different epigenetic states and gene expression profiles. The change in methylation at these regions is associated with the presence of sRNAs. Loci without any sRNA activity can have altered methylation states, suggesting that a sRNA-independent mechanism may also contribute to the altered methylation state of the F1 and F2 generations.
Collapse
|