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Wang C, Chen Z, Copenhaver GP, Wang Y. Heterochromatin in plant meiosis. Nucleus 2024; 15:2328719. [PMID: 38488152 PMCID: PMC10950279 DOI: 10.1080/19491034.2024.2328719] [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: 09/11/2023] [Accepted: 03/05/2024] [Indexed: 03/19/2024] Open
Abstract
Heterochromatin is an organizational property of eukaryotic chromosomes, characterized by extensive DNA and histone modifications, that is associated with the silencing of transposable elements and repetitive sequences. Maintaining heterochromatin is crucial for ensuring genomic integrity and stability during the cell cycle. During meiosis, heterochromatin is important for homologous chromosome synapsis, recombination, and segregation, but our understanding of meiotic heterochromatin formation and condensation is limited. In this review, we focus on the dynamics and features of heterochromatin and how it condenses during meiosis in plants. We also discuss how meiotic heterochromatin influences the interaction and recombination of homologous chromosomes during prophase I.
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Affiliation(s)
- Cong Wang
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Zhiyu Chen
- State Key Laboratory of Genetic Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
| | - Gregory P. Copenhaver
- Department of Biology and the Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Yingxiang Wang
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
- State Key Laboratory of Genetic Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
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2
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Fuentes RR, Nieuwenhuis R, Chouaref J, Hesselink T, van Dooijeweert W, van den Broeck HC, Schijlen E, Schouten HJ, Bai Y, Fransz P, Stam M, de Jong H, Trivino SD, de Ridder D, van Dijk ADJ, Peters SA. A catalogue of recombination coldspots in interspecific tomato hybrids. PLoS Genet 2024; 20:e1011336. [PMID: 38950081 PMCID: PMC11244794 DOI: 10.1371/journal.pgen.1011336] [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: 12/17/2023] [Revised: 07/12/2024] [Accepted: 06/09/2024] [Indexed: 07/03/2024] Open
Abstract
Increasing natural resistance and resilience in plants is key for ensuring food security within a changing climate. Breeders improve these traits by crossing cultivars with their wild relatives and introgressing specific alleles through meiotic recombination. However, some genomic regions are devoid of recombination especially in crosses between divergent genomes, limiting the combinations of desirable alleles. Here, we used pooled-pollen sequencing to build a map of recombinant and non-recombinant regions between tomato and five wild relatives commonly used for introgressive tomato breeding. We detected hybrid-specific recombination coldspots that underscore the role of structural variations in modifying recombination patterns and maintaining genetic linkage in interspecific crosses. Crossover regions and coldspots show strong association with specific TE superfamilies exhibiting differentially accessible chromatin between somatic and meiotic cells. About two-thirds of the genome are conserved coldspots, located mostly in the pericentromeres and enriched with retrotransposons. The coldspots also harbor genes associated with agronomic traits and stress resistance, revealing undesired consequences of linkage drag and possible barriers to breeding. We presented examples of linkage drag that can potentially be resolved by pairing tomato with other wild species. Overall, this catalogue will help breeders better understand crossover localization and make informed decisions on generating new tomato varieties.
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Affiliation(s)
- Roven Rommel Fuentes
- Bioinformatics Group, Wageningen University and Research, Wageningen, The Netherlands
- Chromosome Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Ronald Nieuwenhuis
- Business Unit of Bioscience, Cluster Applied Bioinformatics, Wageningen University and Research, Wageningen, The Netherlands
| | - Jihed Chouaref
- Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Thamara Hesselink
- Business Unit of Bioscience, Cluster Applied Bioinformatics, Wageningen University and Research, Wageningen, The Netherlands
| | - Willem van Dooijeweert
- Centre for Genetic Resources, Wageningen University and Research, Wageningen, The Netherlands
| | - Hetty C van den Broeck
- Business Unit of Bioscience, Cluster Applied Bioinformatics, Wageningen University and Research, Wageningen, The Netherlands
| | - Elio Schijlen
- Business Unit of Bioscience, Cluster Applied Bioinformatics, Wageningen University and Research, Wageningen, The Netherlands
| | - Henk J Schouten
- Plant Breeding, Wageningen University and Research, Wageningen, The Netherlands
| | - Yuling Bai
- Plant Breeding, Wageningen University and Research, Wageningen, The Netherlands
| | - Paul Fransz
- Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Maike Stam
- Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Hans de Jong
- Laboratory of Genetics, Wageningen University and Research, Wageningen, The Netherlands
| | - Sara Diaz Trivino
- Business Unit of Bioscience, Cluster Applied Bioinformatics, Wageningen University and Research, Wageningen, The Netherlands
| | - Dick de Ridder
- Bioinformatics Group, Wageningen University and Research, Wageningen, The Netherlands
| | - Aalt D J van Dijk
- Bioinformatics Group, Wageningen University and Research, Wageningen, The Netherlands
| | - Sander A Peters
- Business Unit of Bioscience, Cluster Applied Bioinformatics, Wageningen University and Research, Wageningen, The Netherlands
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3
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Castellani M, Zhang M, Thangavel G, Mata-Sucre Y, Lux T, Campoy JA, Marek M, Huettel B, Sun H, Mayer KFX, Schneeberger K, Marques A. Meiotic recombination dynamics in plants with repeat-based holocentromeres shed light on the primary drivers of crossover patterning. NATURE PLANTS 2024; 10:423-438. [PMID: 38337039 PMCID: PMC10954556 DOI: 10.1038/s41477-024-01625-y] [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: 08/24/2023] [Accepted: 01/15/2024] [Indexed: 02/12/2024]
Abstract
Centromeres strongly affect (epi)genomic architecture and meiotic recombination dynamics, influencing the overall distribution and frequency of crossovers. Here we show how recombination is regulated and distributed in the holocentric plant Rhynchospora breviuscula, a species with diffused centromeres. Combining immunocytochemistry, chromatin analysis and high-throughput single-pollen sequencing, we discovered that crossover frequency is distally biased, in sharp contrast to the diffused distribution of hundreds of centromeric units and (epi)genomic features. Remarkably, we found that crossovers were abolished inside centromeric units but not in their proximity, indicating the absence of a canonical centromere effect. We further propose that telomere-led synapsis of homologues is the feature that best explains the observed recombination landscape. Our results hint at the primary influence of mechanistic features of meiotic pairing and synapsis rather than (epi)genomic features and centromere organization in determining the distally biased crossover distribution in R. breviuscula, whereas centromeres and (epi)genetic properties only affect crossover positioning locally.
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Affiliation(s)
- Marco Castellani
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Meng Zhang
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Gokilavani Thangavel
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Yennifer Mata-Sucre
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Centre of Biosciences, Federal University of Pernambuco, Recife, Brazil
| | - Thomas Lux
- Plant Genome and Systems Biology, German Research Centre for Environmental Health, Helmholtz Zentrum München, Neuherberg, Germany
| | - José A Campoy
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany
- Department of Pomology, Estación Experimental de Aula Dei (EEAD), Consejo Superior de Investigaciones Científicas, Zaragoza, Spain
| | - Magdalena Marek
- Max Planck Genome-Centre Cologne, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Bruno Huettel
- Max Planck Genome-Centre Cologne, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Hequan Sun
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany
- Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
- School of Automation Science and Engineering, Faculty of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, China
| | - Klaus F X Mayer
- Plant Genome and Systems Biology, German Research Centre for Environmental Health, Helmholtz Zentrum München, Neuherberg, Germany
- School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Korbinian Schneeberger
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany
- Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
- Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich-Heine University, Düsseldorf, Germany
| | - André Marques
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany.
- Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich-Heine University, Düsseldorf, Germany.
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4
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Chowdary KVSKA, Saini R, Singh AK. Epigenetic regulation during meiosis and crossover. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2023; 29:1945-1958. [PMID: 38222277 PMCID: PMC10784443 DOI: 10.1007/s12298-023-01390-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 11/01/2023] [Accepted: 11/10/2023] [Indexed: 01/16/2024]
Abstract
Meiosis is a distinctive type of cell division that reorganizes genetic material between generations. The initial stages of meiosis consist of several crucial steps which include double strand break, homologous chromosome pairing, break repair and crossover. Crossover frequency varies depending on the position on the chromosome, higher at euchromatin region and rare at heterochromatin, centromeres, telomeres and ribosomal DNA. Crossover positioning is dependent on various factors, especially epigenetic modifications. DNA methylation, histone post-translational modifications, histone variants and non-coding RNAs are most probably playing an important role in positioning of crossovers on a chromosomal level as well as hotspot level. DNA methylation negatively regulates crossover frequency and its effect is visible in centromeres, pericentromeres and heterochromatin regions. Pericentromeric chromatin and heterochromatin mark studies have been a centre of attraction in meiosis. Crossover hotspots are associated with euchromatin regions having specific chromatin modifications such as H3K4me3, H2A.Z. and H3 acetylation. This review will provide the current understanding of the epigenetic role in plants during meiotic recombination, chromosome synapsis, double strand break and hotspots with special attention to euchromatin and heterochromatin marks. Further, the role of epigenetic modifications in regulating meiosis and crossover in other organisms is also discussed.
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Affiliation(s)
- K. V. S. K. Arjun Chowdary
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021 India
| | - Ramswaroop Saini
- Department of Biotechnology, Joy University, Vadakangulam, Tirunelveli, Tamil Nadu 627116 India
| | - Amit Kumar Singh
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021 India
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5
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Baker Z, Przeworski M, Sella G. Down the Penrose stairs, or how selection for fewer recombination hotspots maintains their existence. eLife 2023; 12:e83769. [PMID: 37830496 DOI: 10.7554/elife.83769] [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: 09/28/2022] [Accepted: 10/12/2023] [Indexed: 10/14/2023] Open
Abstract
In many species, meiotic recombination events tend to occur in narrow intervals of the genome, known as hotspots. In humans and mice, double strand break (DSB) hotspot locations are determined by the DNA-binding specificity of the zinc finger array of the PRDM9 protein, which is rapidly evolving at residues in contact with DNA. Previous models explained this rapid evolution in terms of the need to restore PRDM9 binding sites lost to gene conversion over time, under the assumption that more PRDM9 binding always leads to more DSBs. This assumption, however, does not align with current evidence. Recent experimental work indicates that PRDM9 binding on both homologs facilitates DSB repair, and that the absence of sufficient symmetric binding disrupts meiosis. We therefore consider an alternative hypothesis: that rapid PRDM9 evolution is driven by the need to restore symmetric binding because of its role in coupling DSB formation and efficient repair. To this end, we model the evolution of PRDM9 from first principles: from its binding dynamics to the population genetic processes that govern the evolution of the zinc finger array and its binding sites. We show that the loss of a small number of strong binding sites leads to the use of a greater number of weaker ones, resulting in a sharp reduction in symmetric binding and favoring new PRDM9 alleles that restore the use of a smaller set of strong binding sites. This decrease, in turn, drives rapid PRDM9 evolutionary turnover. Our results therefore suggest that the advantage of new PRDM9 alleles is in limiting the number of binding sites used effectively, rather than in increasing net PRDM9 binding. By extension, our model suggests that the evolutionary advantage of hotspots may have been to increase the efficiency of DSB repair and/or homolog pairing.
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Affiliation(s)
- Zachary Baker
- Department of Systems Biology, Columbia University, New York, United States
- Department of Biological Sciences, Columbia University, New York, United States
| | - Molly Przeworski
- Department of Systems Biology, Columbia University, New York, United States
- Department of Biological Sciences, Columbia University, New York, United States
- Program for Mathematical Genomics, Columbia University, New York, United States
| | - Guy Sella
- Department of Biological Sciences, Columbia University, New York, United States
- Program for Mathematical Genomics, Columbia University, New York, United States
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Li G, Wu Y, Bai Y, Zhao N, Jiang Y, Li N, Lin X, Liu B, Xu C. Patterns of Chromosomal Variation, Homoeologous Exchange, and Their Relationship with Genomic Features in Early Generations of a Synthetic Rice Segmental Allotetraploid. Int J Mol Sci 2023; 24:ijms24076065. [PMID: 37047036 PMCID: PMC10094486 DOI: 10.3390/ijms24076065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 03/10/2023] [Accepted: 03/21/2023] [Indexed: 04/14/2023] Open
Abstract
Polyploidization is a driving force in plant evolution. Chromosomal variation often occurs at early generations following polyploid formation due to meiotic pairing irregularity that may compromise segregation fidelity and cause homoeologous exchange (HE). The trends of chromosomal variation and especially factors affecting HE remain to be fully deciphered. Here, by whole-genome resequencing, we performed nuanced analyses of patterns of chromosomal number variation and explored genomic features that affect HE in two early generations of a synthetic rice segmental allotetraploid. We found a wide occurrence of whole-chromosome aneuploidy and, to a lesser extent, also large segment gains/losses in both generations (S2 and S4) of the tetraploids. However, while the number of chromosome gains was similar between S2 and S4, that of losses in S4 was lower than in S2. HEs were abundant across all chromosomes in both generations and showed variable correlations with different genomic features at chromosomal and/or local scales. Contents of genes and transposable elements (TEs) were positively and negatively correlated with HE frequencies, respectively. By dissecting TEs into different classes, retrotransposons were found to be negatively correlated with HE frequency to a stronger extent than DNA transposons, whereas miniature terminal inverted elements (MITEs) showed a strong positive correlation. Local HE frequencies in the tetraploids and homologous recombination (HR) rates in diploids within 1 Mb sliding windows were significantly correlated with each other and showed similar overall distribution profiles. Nonetheless, non-concordant trends between HE and HR rates were found at distal regions in some chromosomes. At local scale, both shared and polymorphic retrotransposons between parents were negatively correlated with HE frequency; in contrast, both shared and polymorphic MITEs showed positive correlations with HE frequency. Our results shed new light on the patterns of chromosomal number variation and reveal genomic features influencing HE frequency in early generations following plant polyploidization.
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Affiliation(s)
- Guo Li
- Key Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China
| | - Ying Wu
- Key Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China
| | - Yan Bai
- Key Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China
- Key Laboratory of Molecular Cytogenetics and Genetic Breeding of Heilongjiang Province, College of Life Science and Technology, Harbin Normal University, Harbin 150025, China
| | - Na Zhao
- Department of Agronomy, Jilin Agricultural University, Changchun 130118, China
| | - Yuhui Jiang
- Key Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China
| | - Ning Li
- Key Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China
| | - Xiuyun Lin
- Jilin Academy of Agriculture, Changchun 130033, China
| | - Bao Liu
- Key Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China
| | - Chunming Xu
- Key Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China
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7
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Ma X, Fan L, Zhang Z, Yang X, Liu Y, Ma Y, Pan Y, Zhou G, Zhang M, Ning H, Kong F, Ma J, Liu S, Tian Z. Global dissection of the recombination landscape in soybean using a high-density 600K SoySNP array. PLANT BIOTECHNOLOGY JOURNAL 2023; 21:606-620. [PMID: 36458856 PMCID: PMC9946146 DOI: 10.1111/pbi.13975] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 12/09/2022] [Accepted: 11/27/2022] [Indexed: 05/17/2023]
Abstract
Recombination is crucial for crop breeding because it can break linkage drag and generate novel allele combinations. However, the high-resolution recombination landscape and its driving forces in soybean are largely unknown. Here, we constructed eight recombinant inbred line (RIL) populations and genotyped individual lines using the high-density 600K SoySNP array, which yielded a high-resolution recombination map with 5636 recombination sites at a resolution of 1.37 kb. The recombination rate was negatively correlated with transposable element density and GC content but positively correlated with gene density. Interestingly, we found that meiotic recombination was enriched at the promoters of active genes. Further investigations revealed that chromatin accessibility and active epigenetic modifications promoted recombination. Our findings provide important insights into the control of homologous recombination and thus will increase our ability to accelerate soybean breeding by manipulating meiotic recombination rate.
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Affiliation(s)
- Xin Ma
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovative Academy for Seed DesignChinese Academy of SciencesBeijingChina
| | - Lei Fan
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovative Academy for Seed DesignChinese Academy of SciencesBeijingChina
| | - Zhifang Zhang
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovative Academy for Seed DesignChinese Academy of SciencesBeijingChina
| | - Xia Yang
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovative Academy for Seed DesignChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Yucheng Liu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovative Academy for Seed DesignChinese Academy of SciencesBeijingChina
| | - Yanming Ma
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovative Academy for Seed DesignChinese Academy of SciencesBeijingChina
| | - Yi Pan
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovative Academy for Seed DesignChinese Academy of SciencesBeijingChina
| | - Guoan Zhou
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovative Academy for Seed DesignChinese Academy of SciencesBeijingChina
| | - Min Zhang
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovative Academy for Seed DesignChinese Academy of SciencesBeijingChina
| | - Hailong Ning
- Key Laboratory of Soybean Biology, Chinese Ministry of EducationNortheast Agricultural UniversityHarbinChina
| | - Fanjiang Kong
- Innovative Center of Molecular Genetics and Evolution, School of Life SciencesGuangzhou UniversityGuangzhouChina
| | - Junkui Ma
- The Industrial Crop InstituteShanxi Agricultural UniversityTaiyuanChina
| | - Shulin Liu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovative Academy for Seed DesignChinese Academy of SciencesBeijingChina
| | - Zhixi Tian
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovative Academy for Seed DesignChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
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8
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Wang C, Li X, Huang J, Ma H, Wang CJR, Wang Y. Isolation of Meiocytes and Cytological Analyses of Male Meiotic Chromosomes in Soybean, Lettuce, and Maize. Methods Mol Biol 2023; 2686:219-239. [PMID: 37540360 DOI: 10.1007/978-1-0716-3299-4_9] [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: 08/05/2023]
Abstract
Meiosis is a specialized cell division that halves the number of chromosomes following a single round of DNA replication, thus leading to the generation of haploid gametes. It is essential for sexual reproduction in eukaryotes. Over the past several decades, with the well-developed molecular and cytogenetic methods, there have been great advances in understanding meiosis in plants such as Arabidopsis thaliana and maize, providing excellent references to study meiosis in other plants. A chapter in the previous edition described molecular cytological methods for studying Arabidopsis meiosis in detail. In this chapter, we focus on methods for studying meiosis in soybean (Glycine max), lettuce (Lactuca sativa), and maize (Zea mays). Moreover, we include the method that was recently developed for examination of epigenetic modifications, such as DNA methylation and histone modifications on meiotic chromosomes in plants.
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Affiliation(s)
- Cong Wang
- College of Life Sciences, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Xiang Li
- College of Horticulture, Henan Agricultural University, Zhengzhou, China
| | - Jiyue Huang
- College of Life Sciences, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Hong Ma
- Department of Biology and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
| | | | - Yingxiang Wang
- College of Life Sciences, South China Agricultural University, Guangzhou, China.
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.
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9
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Lee HJ, Choi CH. Characterization of SN38-resistant T47D breast cancer cell sublines overexpressing BCRP, MRP1, MRP2, MRP3, and MRP4. BMC Cancer 2022; 22:446. [PMID: 35461219 PMCID: PMC9035251 DOI: 10.1186/s12885-022-09446-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 03/22/2022] [Indexed: 12/31/2022] Open
Abstract
Background Although several novel resistant breast cancer cell lines have been established, only a few resistant breast cancer cell lines overexpress breast cancer resistance proteins (BCRP). The aim of this study was to establish new resistant breast cancer cell lines overexpressing BCRP using SN38 (7-ethyl-10-hydroxycamptothecin), an active metabolite of irinotecan and was to discover genes and mechanisms associated with multidrug resistance. Methods SN38-resistant T47D breast cancer cell sublines were selected from the wild-type T47D cells by gradually increasing SN38 concentration. The sensitivity of the cells to anti-cancer drugs was assessed by 3-(4,5-methylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. Expression profiles of the resistance-related transporters were examined using RT-qPCR, and western blot analysis. Intracellular fluorescent dye accumulation in the resistant cells was determined using flow cytometry. Results The SN38-resistant T47D breast cancer cell sublines T47D/SN120 and T47D/SN150 were established after long-term exposure (more than 16 months) of wild-type T47D cells to 120 nM and 150 nM SN38, respectively. T47D/SN120 and T47D/SN150 cells were more resistant to SN38 (14.5 and 59.1 times, respectively), irinotecan (1.5 and 3.7 times, respectively), and topotecan (4.9 and 12 times, respectively), than the wild-type parental cells. Both T47D/SN120 and T47D/SN150 sublines were cross-resistant to various anti-cancer drugs. These resistant sublines overexpressed mRNAs of MRP1, MRP2, MRP3, MRP4, and BCRP. The DNA methylase inhibitor 5-aza-2′-deoxycytidine and the histone deacetylase inhibitor trichostatin A increased the expression levels of BCRP, MRP1, MRP2, MRP3, and MRP4 transcripts in T47D/WT cells. Fluorescent dye accumulation was found to be lower in T47D/SN120 and T47D/SN150 cells, compared to that in T47D/WT cells. However, treatment with known chemosensitizers increased the intracellular fluorescent dye accumulation and sensitivity of anti-tumor agents. Conclusion T47D/SN120 and T47D/SN150 cells overexpressed MRP1, MRP2, MRP3, MRP4, and BCRP, which might be due to the suppression of epigenetic gene silencing via DNA hypermethylation and histone deacetylation. Although these resistant cells present a higher resistance to various anti-cancer drugs than their parental wild-type cells, multidrug resistance was overcome by treatment with chemosensitizers. These SN38 resistant T47D breast cancer cell sublines expressing resistance proteins can be useful for the development of new chemosensitizers. Supplementary Information The online version contains supplementary material available at 10.1186/s12885-022-09446-y.
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10
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Fayos I, Frouin J, Meynard D, Vernet A, Herbert L, Guiderdoni E. Manipulation of Meiotic Recombination to Hasten Crop Improvement. BIOLOGY 2022; 11:369. [PMID: 35336743 PMCID: PMC8945028 DOI: 10.3390/biology11030369] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 02/22/2022] [Accepted: 02/23/2022] [Indexed: 01/15/2023]
Abstract
Reciprocal (cross-overs = COs) and non-reciprocal (gene conversion) DNA exchanges between the parental chromosomes (the homologs) during meiotic recombination are, together with mutation, the drivers for the evolution and adaptation of species. In plant breeding, recombination combines alleles from genetically diverse accessions to generate new haplotypes on which selection can act. In recent years, a spectacular progress has been accomplished in the understanding of the mechanisms underlying meiotic recombination in both model and crop plants as well as in the modulation of meiotic recombination using different strategies. The latter includes the stimulation and redistribution of COs by either modifying environmental conditions (e.g., T°), harnessing particular genomic situations (e.g., triploidy in Brassicaceae), or inactivating/over-expressing meiotic genes, notably some involved in the DNA double-strand break (DSB) repair pathways. These tools could be particularly useful for shuffling diversity in pre-breeding generations. Furthermore, thanks to the site-specific properties of genome editing technologies the targeting of meiotic recombination at specific chromosomal regions nowadays appears an attainable goal. Directing COs at desired chromosomal positions would allow breaking linkage situations existing between favorable and unfavorable alleles, the so-called linkage drag, and accelerate genetic gain. This review surveys the recent achievements in the manipulation of meiotic recombination in plants that could be integrated into breeding schemes to meet the challenges of deploying crops that are more resilient to climate instability, resistant to pathogens and pests, and sparing in their input requirements.
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Affiliation(s)
- Ian Fayos
- Meiogenix, 38 rue Sevran, 75011 Paris, France; (I.F.); (L.H.)
| | - Julien Frouin
- CIRAD, UMR AGAP Institut, F-34398 Montpellier, France; (J.F.); (D.M.); (A.V.)
- UMR AGAP Institut, Université de Montpellier, CIRAD, INRAE, Institut Agro, F-34398 Montpellier, France
| | - Donaldo Meynard
- CIRAD, UMR AGAP Institut, F-34398 Montpellier, France; (J.F.); (D.M.); (A.V.)
- UMR AGAP Institut, Université de Montpellier, CIRAD, INRAE, Institut Agro, F-34398 Montpellier, France
| | - Aurore Vernet
- CIRAD, UMR AGAP Institut, F-34398 Montpellier, France; (J.F.); (D.M.); (A.V.)
- UMR AGAP Institut, Université de Montpellier, CIRAD, INRAE, Institut Agro, F-34398 Montpellier, France
| | - Léo Herbert
- Meiogenix, 38 rue Sevran, 75011 Paris, France; (I.F.); (L.H.)
| | - Emmanuel Guiderdoni
- CIRAD, UMR AGAP Institut, F-34398 Montpellier, France; (J.F.); (D.M.); (A.V.)
- UMR AGAP Institut, Université de Montpellier, CIRAD, INRAE, Institut Agro, F-34398 Montpellier, France
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11
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Geng X, Xia Y, Chen H, Du K, Yang J, Kang X. High-Frequency Homologous Recombination Occurred Preferentially in Populus. Front Genet 2021; 12:703077. [PMID: 34490036 PMCID: PMC8417060 DOI: 10.3389/fgene.2021.703077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/14/2021] [Indexed: 11/13/2022] Open
Abstract
Homologous recombination (HR), the most significant event in meiosis, has important implications for genetic diversity and evolution in organisms. Heteroduplex DNA (hDNA), the product of HR, can be captured by artificially induced chromosome doubling during the development of the embryo sac to inhibit postmeiotic segregation, subsequently, and hDNAs are directly detected using codominant simple sequence repeat (SSR) markers. In the present study, two hybrid triploid populations derived from doubling the chromosomes of the embryo sac induced by high temperature in Populus tomentosa served as starting materials. Eighty-seven, 62, and 79 SSR markers on chromosomes 01, 04, and 19, respectively, that were heterozygous in the maternal parent and different from the paternal parent were screened to detect and characterize the hDNA in P. tomentosa. The results showed that the hDNA frequency patterns on chromosomes changed slightly when the number of SSR primers increased. The highest hDNA frequency occurred at the adjacent terminal on chromosomes, which was slightly higher than those at the terminals in the two genotypic individuals, and the hDNA frequency gradually decreased as the locus-centromere distance decreased. With the increase in the number of SSR markers employed for detection, the number of recombination events (REs) detected significantly increased. In regions with high methylation or long terminal repeat (LTR) retrotransposon enrichment, the frequency of hDNA was low, and high frequencies were observed in regions with low sequence complexity and high gene density. High-frequency recombination occurring at high gene density regions strongly affected the association between molecular markers and quantitative trait loci (QTLs), which was an important factor contributing to the difficulty encountered by MAS in achieving the expected breeding results.
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Affiliation(s)
- Xining Geng
- Henan Province Key Laboratory of Germplasm Innovation and Utilization of Eco-Economic Woody Plant, Pingdingshan University, Pingdingshan, China.,Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China.,Beijing Laboratory of Urban and Rural Ecological Environment, Beijing Forestry University, Beijing, China
| | - Yufei Xia
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China.,Beijing Laboratory of Urban and Rural Ecological Environment, Beijing Forestry University, Beijing, China
| | - Hao Chen
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China.,Beijing Laboratory of Urban and Rural Ecological Environment, Beijing Forestry University, Beijing, China
| | - Kang Du
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China.,Beijing Laboratory of Urban and Rural Ecological Environment, Beijing Forestry University, Beijing, China
| | - Jun Yang
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China.,Beijing Laboratory of Urban and Rural Ecological Environment, Beijing Forestry University, Beijing, China
| | - Xiangyang Kang
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China.,Beijing Laboratory of Urban and Rural Ecological Environment, Beijing Forestry University, Beijing, China
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12
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Ahn YJ, Cuacos M, Ayoub MA, Kappermann J, Houben A, Heckmann S. In Planta Delivery of Chemical Compounds into Barley Meiocytes: EdU as Compound Example. Methods Mol Biol 2020; 2061:381-402. [PMID: 31583674 DOI: 10.1007/978-1-4939-9818-0_27] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Here, we describe a protocol for in planta delivery of chemical compounds into meiocytes of different barley genotypes not impacting plant fertility allowing to harvest seeds from treated plants. Compound uptake into meiocytes is assessed by determining 5-ethynyl-2'-deoxyuridine (EdU) incorporation. Similar to EdU, other compounds being soluble in an aqueous solution can be delivered in planta before/during meiosis to decipher their impact on meiosis and meiotic recombination.We give practical advice on how to deliver EdU as compound example (delivery via injection or needle and thread, addition of detergents or surfactants to increase compound uptake), how in planta compound delivery can be established for your plant material under specific growing conditions, how to generate and characterize barley hybrid plants, and how to conduct a meiotic cytological study of (treated) barley plants.
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Affiliation(s)
- Yun-Jae Ahn
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Stadt Seeland, Germany
| | - Maria Cuacos
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Stadt Seeland, Germany
| | - Mohammad A Ayoub
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) OT Gatersleben, Stadt Seeland, Germany
| | - Judith Kappermann
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Stadt Seeland, Germany
| | - Andreas Houben
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Stadt Seeland, Germany
| | - Stefan Heckmann
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Stadt Seeland, Germany.
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13
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Dreissig S, Maurer A, Sharma R, Milne L, Flavell AJ, Schmutzer T, Pillen K. Natural variation in meiotic recombination rate shapes introgression patterns in intraspecific hybrids between wild and domesticated barley. THE NEW PHYTOLOGIST 2020; 228:1852-1863. [PMID: 32659029 DOI: 10.1111/nph.16810] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Accepted: 07/05/2020] [Indexed: 06/11/2023]
Abstract
Meiotic recombination rates vary considerably between species, populations and individuals. The genetic exchange between homologous chromosomes plays a major role in evolution by breaking linkage between advantageous and deleterious alleles in the case of introgressions. Identifying recombination rate modifiers is thus of both fundamental and practical interest to understand and utilize variation in meiotic recombination rates. We investigated recombination rate variation in a large intraspecific hybrid population (named HEB-25) derived from a cross between domesticated barley and 25 wild barley accessions. We observed quantitative variation in total crossover number with a maximum of a 1.4-fold difference between subpopulations and increased recombination rates across pericentromeric regions. The meiosis-specific α-kleisin cohesin subunit REC8 was identified as a candidate gene influencing crossover number and patterning. Furthermore, we quantified wild barley introgression patterns and revealed how local and genome-wide recombination rate variation shapes patterns of introgression. The identification of allelic variation in REC8 in combination with the observed changes in crossover patterning suggest a difference in how chromatin loops are tethered to the chromosome axis, resulting in reduced crossover suppression across pericentromeric regions. Local and genome-wide recombination rate variation is shaping patterns of introgressions and thereby directly influences the consequences of linkage drag.
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Affiliation(s)
- Steven Dreissig
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Betty-Heimann-Straße 3, Halle (Saale), 06120, Germany
| | - Andreas Maurer
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Betty-Heimann-Straße 3, Halle (Saale), 06120, Germany
| | - Rajiv Sharma
- Division of Plant Sciences, University of Dundee at JHI, Invergowrie Dundee, DD2 5DA, Scotland, UK
| | - Linda Milne
- The James Hutton Institute (JHI), Invergowrie Dundee, DD2 5DA, Scotland, UK
| | - Andrew John Flavell
- Division of Plant Sciences, University of Dundee at JHI, Invergowrie Dundee, DD2 5DA, Scotland, UK
| | - Thomas Schmutzer
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Betty-Heimann-Straße 3, Halle (Saale), 06120, Germany
| | - Klaus Pillen
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Betty-Heimann-Straße 3, Halle (Saale), 06120, Germany
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14
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Schwarzkopf EJ, Motamayor JC, Cornejo OE. Genetic differentiation and intrinsic genomic features explain variation in recombination hotspots among cocoa tree populations. BMC Genomics 2020; 21:332. [PMID: 32349675 PMCID: PMC7191684 DOI: 10.1186/s12864-020-6746-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 04/21/2020] [Indexed: 12/16/2022] Open
Abstract
Background Recombination plays an important evolutionary role by breaking up haplotypes and shuffling genetic variation. This process impacts the ability of selection to eliminate deleterious mutations or increase the frequency of beneficial mutations in a population. To understand the role of recombination generating and maintaining haplotypic variation in a population, we can construct fine-scale recombination maps. Such maps have been used to study a variety of model organisms and proven to be informative of how selection and demographics shape species-wide variation. Here we present a fine-scale recombination map for ten populations of Theobroma cacao – a non-model, long-lived, woody crop. We use this map to elucidate the dynamics of recombination rates in distinct populations of the same species, one of which is domesticated. Results Mean recombination rates in range between 2.5 and 8.6 cM/Mb for most populations of T. cacao with the exception of the domesticated Criollo (525 cM/Mb) and Guianna, a more recently established population (46.5 cM/Mb). We found little overlap in the location of hotspots of recombination across populations. We also found that hotspot regions contained fewer known retroelement sequences than expected and were overrepresented near transcription start and termination sites. We find mutations in FIGL-1, a protein shown to downregulate cross-over frequency in Arabidopsis, statistically associated to higher recombination rates in domesticated Criollo. Conclusions We generated fine-scale recombination maps for ten populations of Theobroma cacao and used them to understand what processes are associated with population-level variation in this species. Our results provide support to the hypothesis of increased recombination rates in domesticated plants (Criollo population). We propose a testable mechanistic hypothesis for the change in recombination rate in domesticated populations in the form of mutations to a previously identified recombination-suppressing protein. Finally, we establish a number of possible correlates of recombination hotspots that help explain general patterns of recombination in this species.
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Affiliation(s)
| | | | - Omar E Cornejo
- School of Biological Sciences, Washington State University, Pullman, WA, USA.
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15
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Ahmed AA, Adam Essa ME. Epigenetic alterations in female urogenital organs cancer: Premise, properties, and perspectives. SCIENTIFIC AFRICAN 2020. [DOI: 10.1016/j.sciaf.2020.e00318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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16
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Fayos I, Mieulet D, Petit J, Meunier AC, Périn C, Nicolas A, Guiderdoni E. Engineering meiotic recombination pathways in rice. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:2062-2077. [PMID: 31199561 PMCID: PMC6790369 DOI: 10.1111/pbi.13189] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 06/01/2019] [Accepted: 06/05/2019] [Indexed: 05/02/2023]
Abstract
In the last 15 years, outstanding progress has been made in understanding the function of meiotic genes in the model dicot and monocot plants Arabidopsis and rice (Oryza sativa L.), respectively. This knowledge allowed to modulate meiotic recombination in Arabidopsis and, more recently, in rice. For instance, the overall frequency of crossovers (COs) has been stimulated 2.3- and 3.2-fold through the inactivation of the rice FANCM and RECQ4 DNA helicases, respectively, two genes involved in the repair of DNA double-strand breaks (DSBs) as noncrossovers (NCOs) of the Class II crossover pathway. Differently, the programmed induction of DSBs and COs at desired sites is currently explored by guiding the SPO11-1 topoisomerase-like transesterase, initiating meiotic recombination in all eukaryotes, to specific target regions of the rice genome. Furthermore, the inactivation of 3 meiosis-specific genes, namely PAIR1, OsREC8 and OsOSD1, in the Mitosis instead of Meiosis (MiMe) mutant turned rice meiosis into mitosis, thereby abolishing recombination and achieving the first component of apomixis, apomeiosis. The successful translation of Arabidopsis results into a crop further allowed the implementation of two breakthrough strategies that triggered parthenogenesis from the MiMe unreduced clonal egg cell and completed the second component of diplosporous apomixis. Here, we review the most recent advances in and future prospects of the manipulation of meiotic recombination in rice and potentially other major crops, all essential for global food security.
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Affiliation(s)
- Ian Fayos
- CiradUMR AGAPMontpellierFrance
- Université de MontpellierCirad-Inra-Montpellier SupAgroMontpellierFrance
| | - Delphine Mieulet
- CiradUMR AGAPMontpellierFrance
- Université de MontpellierCirad-Inra-Montpellier SupAgroMontpellierFrance
| | - Julie Petit
- CiradUMR AGAPMontpellierFrance
- Université de MontpellierCirad-Inra-Montpellier SupAgroMontpellierFrance
| | - Anne Cécile Meunier
- CiradUMR AGAPMontpellierFrance
- Université de MontpellierCirad-Inra-Montpellier SupAgroMontpellierFrance
| | - Christophe Périn
- CiradUMR AGAPMontpellierFrance
- Université de MontpellierCirad-Inra-Montpellier SupAgroMontpellierFrance
| | - Alain Nicolas
- Institut Curie, CNRS UMR 3244University PSLParisFrance
- MeiogenixParisFrance
| | - Emmanuel Guiderdoni
- CiradUMR AGAPMontpellierFrance
- Université de MontpellierCirad-Inra-Montpellier SupAgroMontpellierFrance
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17
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Wei C, Wang H, Heng S, Wen J, Yi B, Ma C, Tu J, Shen J, Fu T. Construction of restorer lines and molecular mapping for restorer gene of hau cytoplasmic male sterility in Brassica napus. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2019; 132:2525-2539. [PMID: 31165223 DOI: 10.1007/s00122-019-03368-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 05/27/2019] [Indexed: 06/09/2023]
Abstract
Successfully constructing restorer lines for the hau CMS line and molecular mapping of Rfh to a 94 kb candidate region on chromosome A03 in Brassica napus. Cytoplasmic male sterility is a general phenomenon in almost 200 species, and the interaction between chimeric genes in mitochondria and restorer genes in nucleus may be responsible for restoration of male fertility. Orf288 has been identified as a CMS-associated gene in the hau CMS line of Brassica napus and Brassica juncea; however, the restorer lines/genes have not been found yet. We therefore have successfully constructed two restorer lines in B. napus by extensive testcrossing and have mapped a major restorer gene Rfh to a physical distance of 94 kb on chromosome A03 by whole-genome resequencing and molecular markers. We found that the restorer line is indeed restored to male fertility at histological level. Comparative genomics and collinearity analysis between close relatives revealed that rearrangements and recombination may have happened and thus caused the production of Rfh or components of the restoration of fertility complex. Meanwhile, nuclear backgrounds with multiple loci and temperature were related to the variation and instability of restoration of fertility in three different populations. Our study provides new sights into the coevolution between restorer genes and CMS-associated genes as well as the cultivation of superior hybrids via molecular breeding.
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Affiliation(s)
- Chao Wei
- National Key Laboratory of Crop Genetic Improvement, National Center of Rapeseed Improvement in Wuhan, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan City, 430070, People's Republic of China
- College of Life Science, Zhaoqing University, Zhaoqing, 526061, People's Republic of China
| | - Huadong Wang
- National Key Laboratory of Crop Genetic Improvement, National Center of Rapeseed Improvement in Wuhan, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan City, 430070, People's Republic of China
| | - Shuangping Heng
- National Key Laboratory of Crop Genetic Improvement, National Center of Rapeseed Improvement in Wuhan, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan City, 430070, People's Republic of China
- College of Life Science, Institute for Conservation and Utilization of Agro-Bioresources in Dabie Mountains, Xinyang Normal University, Xinyang, 464000, People's Republic of China
| | - Jing Wen
- National Key Laboratory of Crop Genetic Improvement, National Center of Rapeseed Improvement in Wuhan, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan City, 430070, People's Republic of China
| | - Bin Yi
- National Key Laboratory of Crop Genetic Improvement, National Center of Rapeseed Improvement in Wuhan, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan City, 430070, People's Republic of China
| | - Chaozhi Ma
- National Key Laboratory of Crop Genetic Improvement, National Center of Rapeseed Improvement in Wuhan, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan City, 430070, People's Republic of China
| | - Jinxing Tu
- National Key Laboratory of Crop Genetic Improvement, National Center of Rapeseed Improvement in Wuhan, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan City, 430070, People's Republic of China
| | - Jinxiong Shen
- National Key Laboratory of Crop Genetic Improvement, National Center of Rapeseed Improvement in Wuhan, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan City, 430070, People's Republic of China.
| | - Tingdong Fu
- National Key Laboratory of Crop Genetic Improvement, National Center of Rapeseed Improvement in Wuhan, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan City, 430070, People's Republic of China
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18
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Blary A, Jenczewski E. Manipulation of crossover frequency and distribution for plant breeding. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2019; 132:575-592. [PMID: 30483818 PMCID: PMC6439139 DOI: 10.1007/s00122-018-3240-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 11/13/2018] [Indexed: 05/12/2023]
Abstract
The crossovers (COs) that occur during meiotic recombination lead to genetic diversity upon which natural and artificial selection can act. The potential of tinkering with the mechanisms of meiotic recombination to increase the amount of genetic diversity accessible for breeders has been under the research spotlight for years. A wide variety of approaches have been proposed to increase CO frequency, alter CO distribution and induce COs between non-homologous chromosomal regions. For most of these approaches, translational biology will be crucial for demonstrating how these strategies can be of practical use in plant breeding. In this review, we describe how tinkering with meiotic recombination could benefit plant breeding and give concrete examples of how these strategies could be implemented into breeding programs.
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Affiliation(s)
- A Blary
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
- Department of Plant Breeding, IFZ Research Centre for Biosystems, Land Use and Nutrition, Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
| | - E Jenczewski
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France.
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19
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Role of Cis, Trans, and Inbreeding Effects on Meiotic Recombination in Saccharomyces cerevisiae. Genetics 2018; 210:1213-1226. [PMID: 30291109 DOI: 10.1534/genetics.118.301644] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 10/02/2018] [Indexed: 11/18/2022] Open
Abstract
Meiotic recombination is a major driver of genome evolution by creating new genetic combinations. To probe the factors driving variability of meiotic recombination, we used a high-throughput method to measure recombination rates in hybrids between SK1 and a total of 26 Saccharomyces cerevisiae strains from different geographic origins and habitats. Fourteen intervals were monitored for each strain, covering chromosomes VI and XI entirely, and part of chromosome I. We found an average number of crossovers per chromosome ranging between 1.0 and 9.5 across strains ("domesticated" or not), which is higher than the average between 0.5 and 1.5 found in most organisms. In the different intervals analyzed, recombination showed up to ninefold variation across strains but global recombination landscapes along chromosomes varied less. We also built an incomplete diallel experiment to measure recombination rates in one region of chromosome XI in 10 different crosses involving five parental strains. Our overall results indicate that recombination rate is increasingly positively correlated with sequence similarity between homologs (i) in DNA double-strand-break-rich regions within intervals, (ii) in entire intervals, and (iii) at the whole genome scale. Therefore, these correlations cannot be explained by cis effects only. We also estimated that cis and trans effects explained 38 and 17%, respectively, of the variance of recombination rate. In addition, by using a quantitative genetics analysis, we identified an inbreeding effect that reduces recombination rate in homozygous genotypes, while other interaction effects (specific combining ability) or additive effects (general combining ability) are found to be weak. Finally, we measured significant crossover interference in some strains, and interference intensity was positively correlated with crossover number.
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20
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Fuchs LK, Jenkins G, Phillips DW. Anthropogenic Impacts on Meiosis in Plants. FRONTIERS IN PLANT SCIENCE 2018; 9:1429. [PMID: 30323826 PMCID: PMC6172301 DOI: 10.3389/fpls.2018.01429] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 09/07/2018] [Indexed: 05/18/2023]
Abstract
As the human population grows and continues to encroach on the natural environment, organisms that form part of such ecosystems are becoming increasingly exposed to exogenous anthropogenic factors capable of changing their meiotic landscape. Meiotic recombination generates much of the genetic variation in sexually reproducing species and is known to be a highly conserved pathway. Environmental stresses, such as variations in temperature, have long been known to change the pattern of recombination in both model and crop plants, but there are other factors capable of causing genome damage, infertility and meiotic abnormalities. Our agrarian expansion and our increasing usage of agrochemicals unintentionally affect plants via groundwater contamination or spray drift; our industrial developments release heavy metals into the environment; pathogens are spread by climate change and a globally mobile population; imperfect waste treatment plants are unable to remove chemical and pharmaceutical residues from sewage leading to the release of xenobiotics, all with potentially deleterious meiotic effects. In this review, we discuss the major classes of exogenous anthropogenic factors known to affect meiosis in plants, namely environmental stresses, agricultural inputs, heavy metals, pharmaceuticals and pathogens. The possible evolutionary fate of plants thrust into their new anthropogenically imposed environments are also considered.
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Affiliation(s)
| | | | - Dylan W. Phillips
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, United Kingdom
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21
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Gaysinskaya V, Miller BF, De Luca C, van der Heijden GW, Hansen KD, Bortvin A. Transient reduction of DNA methylation at the onset of meiosis in male mice. Epigenetics Chromatin 2018; 11:15. [PMID: 29618374 PMCID: PMC5883305 DOI: 10.1186/s13072-018-0186-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 03/30/2018] [Indexed: 01/12/2023] Open
Abstract
Background Meiosis is a specialized germ cell cycle that generates haploid gametes. In the initial stage of meiosis, meiotic prophase I (MPI), homologous chromosomes pair and recombine. Extensive changes in chromatin in MPI raise an important question concerning the contribution of epigenetic mechanisms such as DNA methylation to meiosis. Interestingly, previous studies concluded that in male mice, genome-wide DNA methylation patters are set in place prior to meiosis and remain constant subsequently. However, no prior studies examined DNA methylation during MPI in a systematic manner necessitating its further investigation. Results In this study, we used genome-wide bisulfite sequencing to determine DNA methylation of adult mouse spermatocytes at all MPI substages, spermatogonia and haploid sperm. This analysis uncovered transient reduction of DNA methylation (TRDM) of spermatocyte genomes. The genome-wide scope of TRDM, its onset in the meiotic S phase and presence of hemimethylated DNA in MPI are all consistent with a DNA replication-dependent DNA demethylation. Following DNA replication, spermatocytes regain DNA methylation gradually but unevenly, suggesting that key MPI events occur in the context of hemimethylated genome. TRDM also uncovers the prior deficit of DNA methylation of LINE-1 retrotransposons in spermatogonia resulting in their full demethylation during TRDM and likely contributing to the observed mRNA and protein expression of some LINE-1 elements in early MPI. Conclusions Our results suggest that contrary to the prevailing view, chromosomes exhibit dynamic changes in DNA methylation in MPI. We propose that TRDM facilitates meiotic prophase processes and gamete quality control. Electronic supplementary material The online version of this article (10.1186/s13072-018-0186-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Valeriya Gaysinskaya
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD, USA.,Department of Biology, Johns Hopkins University, Baltimore, MD, USA
| | - Brendan F Miller
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA.,Translational and Functional Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Chiara De Luca
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD, USA
| | - Godfried W van der Heijden
- Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Center, PO BOX 2040, 3000 CA, Rotterdam, The Netherlands
| | - Kasper D Hansen
- Department of Biostatistics, Johns Hopkins University, Baltimore, MD, USA.,Center for Computational Biology, Johns Hopkins University, Baltimore, MD, USA.,McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Alex Bortvin
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD, USA.
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22
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Laurent B, Palaiokostas C, Spataro C, Moinard M, Zehraoui E, Houston RD, Foulongne‐Oriol M. High-resolution mapping of the recombination landscape of the phytopathogen Fusarium graminearum suggests two-speed genome evolution. MOLECULAR PLANT PATHOLOGY 2018; 19:341-354. [PMID: 27998012 PMCID: PMC6638080 DOI: 10.1111/mpp.12524] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 12/01/2016] [Accepted: 12/03/2016] [Indexed: 05/25/2023]
Abstract
Recombination is a major evolutionary force, increasing genetic diversity and permitting efficient coevolution of fungal pathogen(s) with their host(s). The ascomycete Fusarium graminearum is a devastating pathogen of cereal crops, and can contaminate food and feed with harmful mycotoxins. Previous studies have suggested a high adaptive potential of this pathogen, illustrated by an increase in pathogenicity and resistance to fungicides. In this study, we provide the first detailed picture of the crossover events occurring during meiosis and discuss the role of recombination in pathogen evolution. An experimental recombinant population (n = 88) was created and genotyped using 1306 polymorphic markers obtained from restriction site-associated DNA sequencing (RAD-seq) and aligned to the reference genome. The construction of a high-density linkage map, anchoring 99% of the total length of the reference genome, allowed the identification of 1451 putative crossovers, positioned at a median resolution of 24 kb. The majority of crossovers (87.2%) occurred in a relatively small portion of the genome (30%). All chromosomes demonstrated recombination-active sections, which had a near 15-fold higher crossover rate than non-active recombinant sections. The recombination rate showed a strong positive correlation with nucleotide diversity, and recombination-active regions were enriched for genes with a putative role in host-pathogen interaction, as well as putative diversifying genes. Our results confirm the preliminary analysis observed in other F. graminearum strains and suggest a conserved 'two-speed' recombination landscape. The consequences with regard to the evolutionary potential of this major fungal pathogen are also discussed.
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Affiliation(s)
- Benoit Laurent
- MycSA, INRA, Université de Bordeaux33882Villenave d'OrnonFrance
| | | | - Cathy Spataro
- MycSA, INRA, Université de Bordeaux33882Villenave d'OrnonFrance
| | - Magalie Moinard
- MycSA, INRA, Université de Bordeaux33882Villenave d'OrnonFrance
| | - Enric Zehraoui
- MycSA, INRA, Université de Bordeaux33882Villenave d'OrnonFrance
| | - Ross D. Houston
- The Roslin Institute, University of EdinburghMidlothianEH25 9RGUK
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23
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Sun Y, Svedberg J, Hiltunen M, Corcoran P, Johannesson H. Large-scale suppression of recombination predates genomic rearrangements in Neurospora tetrasperma. Nat Commun 2017; 8:1140. [PMID: 29074958 PMCID: PMC5658415 DOI: 10.1038/s41467-017-01317-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 09/08/2017] [Indexed: 12/21/2022] Open
Abstract
A common feature of eukaryote genomes is large chromosomal regions where recombination is absent or strongly reduced, but the factors that cause this reduction are not well understood. Genomic rearrangements have often been implicated, but they may also be a consequence of recombination suppression rather than a cause. In this study, we generate eight high-quality genomic data sets of the filamentous ascomycete Neurospora tetrasperma, a fungus that lacks recombination over most of its largest chromosome. The genomes surprisingly reveal collinearity of the non-recombining regions and although large inversions are enriched in these regions, we conclude these inversions to be derived and not the cause of the suppression. To our knowledge, this is the first time that non-recombining, genic regions as large as 86% of a full chromosome (or 8 Mbp), are shown to be collinear. These findings are of significant interest for our understanding of the evolution of sex chromosomes and other supergene complexes.
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Affiliation(s)
- Yu Sun
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, 510642, China
| | - Jesper Svedberg
- Department of Organismal Biology, Uppsala University, Norbyvägen 18D, 752 36, Uppsala, Sweden
| | - Markus Hiltunen
- Department of Organismal Biology, Uppsala University, Norbyvägen 18D, 752 36, Uppsala, Sweden
| | - Pádraic Corcoran
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - Hanna Johannesson
- Department of Organismal Biology, Uppsala University, Norbyvägen 18D, 752 36, Uppsala, Sweden.
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24
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Pelé A, Falque M, Trotoux G, Eber F, Nègre S, Gilet M, Huteau V, Lodé M, Jousseaume T, Dechaumet S, Morice J, Poncet C, Coriton O, Martin OC, Rousseau-Gueutin M, Chèvre AM. Amplifying recombination genome-wide and reshaping crossover landscapes in Brassicas. PLoS Genet 2017; 13:e1006794. [PMID: 28493942 PMCID: PMC5444851 DOI: 10.1371/journal.pgen.1006794] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 05/25/2017] [Accepted: 05/02/2017] [Indexed: 11/19/2022] Open
Abstract
Meiotic recombination by crossovers (COs) is tightly regulated, limiting its key role in producing genetic diversity. However, while COs are usually restricted in number and not homogenously distributed along chromosomes, we show here how to disrupt these rules in Brassica species by using allotriploid hybrids (AAC, 2n = 3x = 29), resulting from the cross between the allotetraploid rapeseed (B. napus, AACC, 2n = 4x = 38) and one of its diploid progenitors (B. rapa, AA, 2n = 2x = 20). We produced mapping populations from different genotypes of both diploid AA and triploid AAC hybrids, used as female and/or as male. Each population revealed nearly 3,000 COs that we studied with SNP markers well distributed along the A genome (on average 1 SNP per 1.25 Mbp). Compared to the case of diploids, allotriploid hybrids showed 1.7 to 3.4 times more overall COs depending on the sex of meiosis and the genetic background. Most surprisingly, we found that such a rise was always associated with (i) dramatic changes in the shape of recombination landscapes and (ii) a strong decrease of CO interference. Hybrids carrying an additional C genome exhibited COs all along the A chromosomes, even in the vicinity of centromeres that are deprived of COs in diploids as well as in most studied species. Moreover, in male allotriploid hybrids we found that Class I COs are mostly responsible for the changes of CO rates, landscapes and interference. These results offer the opportunity for geneticists and plant breeders to dramatically enhance the generation of diversity in Brassica species by disrupting the linkage drag coming from limits on number and distribution of COs.
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Affiliation(s)
- Alexandre Pelé
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Matthieu Falque
- GQE-Le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif sur Yvette, France
| | - Gwenn Trotoux
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Frédérique Eber
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Sylvie Nègre
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Marie Gilet
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Virginie Huteau
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Maryse Lodé
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | | | - Sylvain Dechaumet
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Jérôme Morice
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | | | - Olivier Coriton
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Olivier C. Martin
- GQE-Le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif sur Yvette, France
| | | | - Anne-Marie Chèvre
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
- * E-mail:
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25
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Wang G, Köhler C. Epigenetic processes in flowering plant reproduction. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:797-807. [PMID: 28062591 DOI: 10.1093/jxb/erw486] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Seeds provide up to 70% of the energy intake of the human population, emphasizing the relevance of understanding the genetic and epigenetic mechanisms controlling seed formation. In flowering plants, seeds are the product of a double fertilization event, leading to the formation of the embryo and the endosperm surrounded by maternal tissues. Analogous to mammals, plants undergo extensive epigenetic reprogramming during both gamete formation and early seed development, a process that is supposed to be required to enforce silencing of transposable elements and thus to maintain genome stability. Global changes of DNA methylation, histone modifications, and small RNAs are closely associated with epigenome programming during plant reproduction. Here, we review current knowledge on chromatin changes occurring during sporogenesis and gametogenesis, as well as early seed development in major flowering plant models.
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Affiliation(s)
- Guifeng Wang
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
- Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Claudia Köhler
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
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26
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Epigenetic events in male common urogenital organs cancer. JOURNAL OF CANCER RESEARCH AND PRACTICE 2016. [DOI: 10.1016/j.jcrpr.2016.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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27
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Wang K, Huang G, Zhu Y. Transposable elements play an important role during cotton genome evolution and fiber cell development. SCIENCE CHINA-LIFE SCIENCES 2015; 59:112-21. [PMID: 26687725 DOI: 10.1007/s11427-015-4928-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 07/20/2015] [Indexed: 11/26/2022]
Abstract
Transposable elements (TEs) usually occupy largest fractions of plant genome and are also the most variable part of the structure. Although traditionally it is hallmarked as "junk and selfish DNA", today more and more evidence points out TE's participation in gene regulations including gene mutation, duplication, movement and novel gene creation via genetic and epigenetic mechanisms. The recently sequenced genomes of diploid cottons Gossypium arboreum (AA) and Gossypium raimondii (DD) together with their allotetraploid progeny Gossypium hirsutum (AtAtDtDt) provides a unique opportunity to compare genome variations in the Gossypium genus and to analyze the functions of TEs during its evolution. TEs accounted for 57%, 68.5% and 67.2%, respectively in DD, AA and AtAtDtDt genomes. The 1,694 Mb A-genome was found to harbor more LTR(long terminal repeat)-type retrotransposons that made cardinal contributions to the twofold increase in its genome size after evolution from the 775.2 Mb D-genome. Although the 2,173 Mb AtAtDtDt genome showed similar TE content to the A-genome, the total numbers of LTR-gypsy and LTR-copia type TEs varied significantly between these two genomes. Considering their roles on rewiring gene regulatory networks, we believe that TEs may somehow be involved in cotton fiber cell development. Indeed, the insertion or deletion of different TEs in the upstream region of two important transcription factor genes in At or Dt subgenomes resulted in qualitative differences in target gene expression. We suggest that our findings may open a window for improving cotton agronomic traits by editing TE activities.
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Affiliation(s)
- Kun Wang
- College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Gai Huang
- State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, 100871, China
| | - Yuxian Zhu
- College of Life Sciences, Wuhan University, Wuhan, 430072, China.
- Institute for Advanced Studies, Wuhan University, Wuhan, 430072, China.
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