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Hubinský M, Hobza R, Starczak M, Gackowski D, Kubát Z, Janíček T, Horáková L, Rodriguez Lorenzo JL. Non-canonical bases differentially represented in the sex chromosomes of the dioecious plant Silene latifolia. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:3849-3861. [PMID: 38652039 PMCID: PMC11233409 DOI: 10.1093/jxb/erae178] [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: 09/28/2023] [Accepted: 04/22/2024] [Indexed: 04/25/2024]
Abstract
The oxidation of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC), known as oxi-mCs, garners significant interest in plants as potential epigenetic marks. While research in mammals has established a role in cell reprogramming, carcinogenesis, and gene regulation, their functions in plants remain unclear. In rice, 5hmC has been associated with transposable elements (TEs) and heterochromatin. This study utilizes Silene latifolia, a dioecious plant with heteromorphic sex chromosomes and a genome with a large proportion of TEs, which provides a favourable environment for the study of oxi-mCs in individual sexes. Notably, we detected surprisingly high levels of oxi-mCs in S. latifolia comparable with mammals. Nuclei showed enrichment in heterochromatic regions, except for 5hmC whose signal was homogeneously distributed. Intriguingly, the same X chromosome in females displayed overall enrichment of 5hmC and 5fC compared with its counterpart. This fact is shared with 5mC, resembling dosage compensation. Co-localization showed higher correlation between 5mC and 5fC than with 5hmC, indicating no potential relationship between 5hmC and 5fC. Additionally, the promoter of several sex-linked genes and sex-biased TEs clustered in a clear sex-dependent way. Together, these findings unveil a hypothetical role for oxi-mCs in S. latifolia sex chromosome development, warranting further exploration.
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Affiliation(s)
- Marcel Hubinský
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Roman Hobza
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
| | - Marta Starczak
- Department of Clinical Biochemistry, Faculty of Pharmacy, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, ul. Karlowicza 24, PO-85-092, Bydgoszcz, Poland
| | - Daniel Gackowski
- Department of Clinical Biochemistry, Faculty of Pharmacy, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, ul. Karlowicza 24, PO-85-092, Bydgoszcz, Poland
| | - Zdeněk Kubát
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
| | - Tomáš Janíček
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
| | - Lucie Horáková
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
| | - Jose Luis Rodriguez Lorenzo
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
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Zhang GJ, Jia KL, Wang J, Gao WJ, Li SF. Genome-wide analysis of transposable elements and satellite DNA in Humulus scandens, a dioecious plant with XX/XY 1Y 2 chromosomes. FRONTIERS IN PLANT SCIENCE 2023; 14:1230250. [PMID: 37908838 PMCID: PMC10614002 DOI: 10.3389/fpls.2023.1230250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 10/04/2023] [Indexed: 11/02/2023]
Abstract
Transposable elements (TEs) and satellite DNAs, two major categories of repetitive sequences, are expected to accumulate in non-recombining genome regions, including sex-linked regions, and contribute to sex chromosome evolution. The dioecious plant, Humulus scandens, can be used for studying the evolution of the XX/XY1Y2 sex chromosomes. In this study, we thoroughly examined the repetitive components of male and female H. scandens using next-generation sequencing data followed by bioinformatics analysis and florescence in situ hybridization (FISH). The H. scandens genome has a high overall repetitive sequence composition, 68.30% in the female and 66.78% in the male genome, with abundant long terminal repeat (LTR) retrotransposons (RTs), including more Ty3/Gypsy than Ty1/Copia elements, particularly two Ty3/Gypsy lineages, Tekay and Retand. Most LTR-RT lineages were found dispersed across the chromosomes, though CRM and Athila elements were predominately found within the centromeres and the pericentromeric regions. The Athila elements also showed clearly higher FISH signal intensities in the Y1 and Y2 chromosomes than in the X or autosomes. Three novel satellite DNAs were specifically distributed in the centromeric and/or telomeric regions, with markedly different distributions on the X, Y1, and Y2 chromosomes. Combined with FISH using satellite DNAs to stain chromosomes during meiotic diakinesis, we determined the synapsis pattern and distinguish pseudoautosomal regions (PARs). The results indicate that the XY1Y2 sex chromosomes of H. scandens might have originated from a centric fission event. This study improves our understanding of the repetitive sequence organization of H. scandens genome and provides a basis for further analysis of their chromosome evolution process.
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Affiliation(s)
- Guo-Jun Zhang
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, China
- College of Life Sciences, Henan Normal University, Xinxiang, China
| | - Ke-Li Jia
- College of Life Sciences, Henan Normal University, Xinxiang, China
- SanQuan Medical College, Xinxiang Medical University, Xinxiang, China
| | - Jin Wang
- College of Life Sciences, Henan Normal University, Xinxiang, China
| | - Wu-Jun Gao
- College of Life Sciences, Henan Normal University, Xinxiang, China
| | - Shu-Fen Li
- College of Life Sciences, Henan Normal University, Xinxiang, China
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3
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Razumova OV, Divashuk MG, Alexandrov OS, Karlov GI. GISH painting of the Y chromosomes suggests advanced phases of sex chromosome evolution in three dioecious Cannabaceae species (Humulus lupulus, H. japonicus, and Cannabis sativa). PROTOPLASMA 2023; 260:249-256. [PMID: 35595927 DOI: 10.1007/s00709-022-01774-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 05/11/2022] [Indexed: 06/15/2023]
Abstract
In plants, dioecy is relatively rare, and it involves sex chromosome systems that often developed independently over time. These characteristics make dioecious plants an attractive model to study sex chromosome evolution. To clarify the patterns of plant sex chromosome evolution, studies should be performed on a wide range of dioecious species. It is interesting to study the sex chromosomes in related species that evolved during a long period of independent sex chromosome evolution. The Cannabaceae family includes three dioecious species with heteromorphic sex chromosomes. Cannabis sativa and Humulus lupulus use the XX/XY chromosome system, whereas Humulus japonicus contains multiple sex chromosomes (XX/XY1Y2). To better understand sex chromosome evolution and the level of genomic divergence of these three related species, we undertook self-GISH and comparative GISH analyses. The self-GISH allowed visualization of the Y chromosomes of C. sativa, H. lupulus, and H. japonicus. The self-GISH signal was distributed along the entire Y chromosome, excluding the pseudo-autosomal region (PAR). Our results indicate that the male-specific region of the Y chromosome (MSY) spans the overwhelming majority of the Y chromosomes of all three species studied. The self-GISH results reveal the accumulation of repetitive DNA sequences in the Y chromosomes of all three species studied. This sequences presented in autosomes and/or chromosome X at a lower copy number than in Y. In comparative GISH experiments where the probe DNA of one species was applied to another species, a weak signal was exclusively detected on 45S rDNA sites, indicating a high level of genomic differentiation of the species used in this study. We demonstrate small PAR size and opposing large MSY and its positions on Y chromosomes. We also found that these genomes are highly differentiated. Furthermore, the data obtained in this study indicate a long period of independent and advanced sex chromosome evolution. Our study provides a valuable basis for future genomic studies of sex and suggests that the Cannabaceae family offers a promising model to study sex chromosome evolution.
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Affiliation(s)
- Olga V Razumova
- All-Russia Research Institute of Agricultural Biotechnology, Timiryazevskaya 42, Moscow, 127550, Russia
| | - Mikhail G Divashuk
- All-Russia Research Institute of Agricultural Biotechnology, Timiryazevskaya 42, Moscow, 127550, Russia
| | - Oleg S Alexandrov
- All-Russia Research Institute of Agricultural Biotechnology, Timiryazevskaya 42, Moscow, 127550, Russia
| | - Gennady I Karlov
- All-Russia Research Institute of Agricultural Biotechnology, Timiryazevskaya 42, Moscow, 127550, Russia.
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Muyle A, Marais GAB, Bačovský V, Hobza R, Lenormand T. Dosage compensation evolution in plants: theories, controversies and mechanisms. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210222. [PMID: 35306896 PMCID: PMC8935305 DOI: 10.1098/rstb.2021.0222] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In a minority of flowering plants, separate sexes are genetically determined by sex chromosomes. The Y chromosome has a non-recombining region that degenerates, causing a reduced expression of Y genes. In some species, the lower Y expression is accompanied by dosage compensation (DC), a mechanism that re-equalizes male and female expression and/or brings XY male expression back to its ancestral level. Here, we review work on DC in plants, which started as early as the late 1960s with cytological approaches. The use of transcriptomics fired a controversy as to whether DC existed in plants. Further work revealed that various plants exhibit partial DC, including a few species with young and homomorphic sex chromosomes. We are starting to understand the mechanisms responsible for DC in some plants, but in most species, we lack the data to differentiate between global and gene-by-gene DC. Also, it is unknown why some species evolve many dosage compensated genes while others do not. Finally, the forces that drive DC evolution remain mysterious, both in plants and animals. We review the multiple evolutionary theories that have been proposed to explain DC patterns in eukaryotes with XY or ZW sex chromosomes. This article is part of the theme issue 'Sex determination and sex chromosome evolution in land plants'.
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Affiliation(s)
- Aline Muyle
- Laboratoire 'Biométrie et Biologie Evolutive', CNRS/Université Lyon 1, Lyon, France
| | - Gabriel A B Marais
- Laboratoire 'Biométrie et Biologie Evolutive', CNRS/Université Lyon 1, Lyon, France.,CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de Vairão, Universidade do Porto, 4485-661 Vairão, Portugal.,Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, 4099-002 Porto, Portugal.,BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661 Vairão, Portugal
| | - Václav Bačovský
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, Brno, Czech Republic
| | - Roman Hobza
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, Brno, Czech Republic
| | - Thomas Lenormand
- CEFE, University of Montpellier, CNRS, EPHE, IRD, Montpellier, France
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Garrido-Ramos MA. The Genomics of Plant Satellite DNA. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2021; 60:103-143. [PMID: 34386874 DOI: 10.1007/978-3-030-74889-0_5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The twenty-first century began with a certain indifference to the research of satellite DNA (satDNA). Neither genome sequencing projects were able to accurately encompass the study of satDNA nor classic methodologies were able to go further in undertaking a better comprehensive study of the whole set of satDNA sequences of a genome. Nonetheless, knowledge of satDNA has progressively advanced during this century with the advent of new analytical techniques. The enormous advantages that genome-wide approaches have brought to its analysis have now stimulated a renewed interest in the study of satDNA. At this point, we can look back and try to assess more accurately many of the key questions that were left unsolved in the past about this enigmatic and important component of the genome. I review here the understanding gathered on plant satDNAs over the last few decades with an eye on the near future.
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Li N, Li X, Zhou J, Yu L, Li S, Zhang Y, Qin R, Gao W, Deng C. Genome-Wide Analysis of Transposable Elements and Satellite DNAs in Spinacia Species to Shed Light on Their Roles in Sex Chromosome Evolution. FRONTIERS IN PLANT SCIENCE 2021; 11:575462. [PMID: 33519837 PMCID: PMC7840529 DOI: 10.3389/fpls.2020.575462] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 12/17/2020] [Indexed: 05/02/2023]
Abstract
Sex chromosome evolution has mostly been studied in species with heteromorphic sex chromosomes. The Spinacia genus serves as an ideal model for investigating evolutionary mechanisms underlying the transition from homomorphic to heteromorphic sex chromosomes. Among evolutionary factors, repetitive sequences play multiple roles in sex chromosome evolution while their forces have not been fully explored in Spinacia species. Here, we identified major repetitive sequence classes in male and female genomes of Spinacia species and their ancestral relative sugar beet to elucidate the evolutionary processes of sex chromosome evolution using next-generation sequencing (NGS) data. Comparative analysis revealed that the repeat elements of Spinacia species are considerably higher than of sugar beet, especially the Ty3/Gypsy and Ty1/Copia retrotransposons. The long terminal repeat retroelements (LTR) Angela, Athila, and Ogre may be accounted for the higher proportion of repeats in the spinach genome. Comparison of the repeats proportion between female and male genomes of three Spinacia species indicated the different representation in Spinacia tetrandra samples but not in the S. oleracea or S. turkestanica samples. From these results, we speculated that emergence of repetitive DNA sequences may correlate the formation of sex chromosome and the transition from homomorphic sex chromosomes to heteromorphic sex chromosomes as heteromorphic sex chromosomes exclusively existed in Spinacia tetrandra. Three novel sugar beet-specific satellites were identified and confirmed by fluorescence in situ hybridization (FISH); six out of eight new spinach-specific satellites were mapped to the short arm of sex chromosomes. A total of 141 copies of SolSat01-171-s were found in the sex determination region (SDR). Thus, the accumulation of satellite DNA on the short arm of chromosome 1 may be involved in the sex chromosome evolution in Spinacia species. Our study provides a fundamental resource for understanding repeat sequences in Spinacia species and their roles in sex chromosome evolution.
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Affiliation(s)
- Ning Li
- College of Life Sciences, Henan Normal University, Xinxiang, China
| | - Xiaoyue Li
- College of Life Sciences, Henan Normal University, Xinxiang, China
| | - Jian Zhou
- College of Life Sciences, Henan Normal University, Xinxiang, China
| | - Li’ang Yu
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
| | - Shufen Li
- College of Life Sciences, Henan Normal University, Xinxiang, China
| | - Yulan Zhang
- College of Life Sciences, Henan Normal University, Xinxiang, China
| | - Ruiyun Qin
- College of Life Sciences, Henan Normal University, Xinxiang, China
| | - Wujun Gao
- College of Life Sciences, Henan Normal University, Xinxiang, China
| | - Chuanliang Deng
- College of Life Sciences, Henan Normal University, Xinxiang, China
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Jesionek W, Bodláková M, Kubát Z, Čegan R, Vyskot B, Vrána J, Šafář J, Puterova J, Hobza R. Fundamentally different repetitive element composition of sex chromosomes in Rumex acetosa. ANNALS OF BOTANY 2021; 127:33-47. [PMID: 32902599 PMCID: PMC7750719 DOI: 10.1093/aob/mcaa160] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 08/31/2020] [Indexed: 05/10/2023]
Abstract
BACKGROUND AND AIMS Dioecious species with well-established sex chromosomes are rare in the plant kingdom. Most sex chromosomes increase in size but no comprehensive analysis of the kind of sequences that drive this expansion has been presented. Here we analyse sex chromosome structure in common sorrel (Rumex acetosa), a dioecious plant with XY1Y2 sex determination, and we provide the first chromosome-specific repeatome analysis for a plant species possessing sex chromosomes. METHODS We flow-sorted and separately sequenced sex chromosomes and autosomes in R. acetosa using the two-dimensional fluorescence in situ hybridization in suspension (FISHIS) method and Illumina sequencing. We identified and quantified individual repeats using RepeatExplorer, Tandem Repeat Finder and the Tandem Repeats Analysis Program. We employed fluorescence in situ hybridization (FISH) to analyse the chromosomal localization of satellites and transposons. KEY RESULTS We identified a number of novel satellites, which have, in a fashion similar to previously known satellites, significantly expanded on the Y chromosome but not as much on the X or on autosomes. Additionally, the size increase of Y chromosomes is caused by non-long terminal repeat (LTR) and LTR retrotransposons, while only the latter contribute to the enlargement of the X chromosome. However, the X chromosome is populated by different LTR retrotransposon lineages than those on Y chromosomes. CONCLUSIONS The X and Y chromosomes have significantly diverged in terms of repeat composition. The lack of recombination probably contributed to the expansion of diverse satellites and microsatellites and faster fixation of newly inserted transposable elements (TEs) on the Y chromosomes. In addition, the X and Y chromosomes, despite similar total counts of TEs, differ significantly in the representation of individual TE lineages, which indicates that transposons proliferate preferentially in either the paternal or the maternal lineage.
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Affiliation(s)
- Wojciech Jesionek
- Department of Plant Developmental Genetics, The Czech Academy of Sciences, Institute of Biophysics, Královopolská, Brno, Czech Republic
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice, Brno, Czech Republic
- For correspondence. E-mail: or
| | - Markéta Bodláková
- Department of Plant Developmental Genetics, The Czech Academy of Sciences, Institute of Biophysics, Královopolská, Brno, Czech Republic
| | - Zdeněk Kubát
- Department of Plant Developmental Genetics, The Czech Academy of Sciences, Institute of Biophysics, Královopolská, Brno, Czech Republic
| | - Radim Čegan
- Department of Plant Developmental Genetics, The Czech Academy of Sciences, Institute of Biophysics, Královopolská, Brno, Czech Republic
| | - Boris Vyskot
- Department of Plant Developmental Genetics, The Czech Academy of Sciences, Institute of Biophysics, Královopolská, Brno, Czech Republic
| | - Jan Vrána
- Institute of Experimental Botany, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů, Olomouc-Holice, Czech Republic
| | - Jan Šafář
- Institute of Experimental Botany, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů, Olomouc-Holice, Czech Republic
| | - Janka Puterova
- Department of Plant Developmental Genetics, The Czech Academy of Sciences, Institute of Biophysics, Královopolská, Brno, Czech Republic
- Brno University of Technology, Faculty of Information Technology, Centre of Excellence IT4Innovations, Bozetechova, Brno, Czech Republic
| | - Roman Hobza
- Department of Plant Developmental Genetics, The Czech Academy of Sciences, Institute of Biophysics, Královopolská, Brno, Czech Republic
- For correspondence. E-mail: or
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Rodríguez Lorenzo JL, Hubinský M, Vyskot B, Hobza R. Histone post-translational modifications in Silene latifolia X and Y chromosomes suggest a mammal-like dosage compensation system. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2020; 299:110528. [PMID: 32900432 DOI: 10.1016/j.plantsci.2020.110528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 05/07/2020] [Accepted: 05/09/2020] [Indexed: 06/11/2023]
Abstract
Silene latifolia is a model organism to study evolutionary young heteromorphic sex chromosome evolution in plants. Previous research indicates a Y-allele gene degeneration and a dosage compensation system already operating. Here, we propose an epigenetic approach based on analysis of several histone post-translational modifications (PTMs) to find the first epigenetic hints of the X:Y sex chromosome system regulation in S. latifolia. Through chromatin immunoprecipitation we interrogated six genes from X and Y alleles. Several histone PTMS linked to DNA methylation and transcriptional repression (H3K27me3, H3K23me, H3K9me2 and H3K9me3) and to transcriptional activation (H3K4me3 and H4K5, 8, 12, 16ac) were used. DNA enrichment (Immunoprecipitated DNA/input DNA) was analyzed and showed three main results: (i) promoters of the Y allele are associated with heterochromatin marks, (ii) promoters of the X allele in males are associated with activation of transcription marks and finally, (iii) promoters of X alleles in females are associated with active and repressive marks. Our finding indicates a transcription activation of X allele and transcription repression of Y allele in males. In females we found a possible differential regulation (up X1, down X2) of each female X allele. These results agree with the mammal-like epigenetic dosage compensation regulation.
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Affiliation(s)
- José Luis Rodríguez Lorenzo
- The Czech Academy of Sciences, Institute of Biophysics v.v.i., Department of Plant Developmental Genetics, Královopolská 135, 612 65, Brno, Czech Republic.
| | - Marcel Hubinský
- The Czech Academy of Sciences, Institute of Biophysics v.v.i., Department of Plant Developmental Genetics, Královopolská 135, 612 65, Brno, Czech Republic
| | - Boris Vyskot
- The Czech Academy of Sciences, Institute of Biophysics v.v.i., Department of Plant Developmental Genetics, Královopolská 135, 612 65, Brno, Czech Republic
| | - Roman Hobza
- The Czech Academy of Sciences, Institute of Biophysics v.v.i., Department of Plant Developmental Genetics, Královopolská 135, 612 65, Brno, Czech Republic
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9
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Baránková S, Pascual-Díaz JP, Sultana N, Alonso-Lifante MP, Balant M, Barros K, D'Ambrosio U, Malinská H, Peska V, Pérez Lorenzo I, Kovařík A, Vyskot B, Janoušek B, Garcia S. Sex-chrom, a database on plant sex chromosomes. THE NEW PHYTOLOGIST 2020; 227:1594-1604. [PMID: 32357248 DOI: 10.1111/nph.16635] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 04/25/2020] [Indexed: 05/15/2023]
Affiliation(s)
- Simona Baránková
- Institut Botanic de Barcelona (IBB-CSIC, Ajuntament de Barcelona), Passeig del Migdia s/n, 08038, Barcelona, Catalonia, Spain
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65, Brno, Czech Republic
| | - Joan Pere Pascual-Díaz
- Institut Botanic de Barcelona (IBB-CSIC, Ajuntament de Barcelona), Passeig del Migdia s/n, 08038, Barcelona, Catalonia, Spain
| | - Nusrat Sultana
- Institut Botanic de Barcelona (IBB-CSIC, Ajuntament de Barcelona), Passeig del Migdia s/n, 08038, Barcelona, Catalonia, Spain
- Department of Botany, Faculty of Life and Earth Sciences, Jagannath University, Dhaka, 1100, Bangladesh
| | - Maria Pilar Alonso-Lifante
- Institut Botanic de Barcelona (IBB-CSIC, Ajuntament de Barcelona), Passeig del Migdia s/n, 08038, Barcelona, Catalonia, Spain
| | - Manica Balant
- Institut Botanic de Barcelona (IBB-CSIC, Ajuntament de Barcelona), Passeig del Migdia s/n, 08038, Barcelona, Catalonia, Spain
| | - Karina Barros
- Institut Botanic de Barcelona (IBB-CSIC, Ajuntament de Barcelona), Passeig del Migdia s/n, 08038, Barcelona, Catalonia, Spain
| | - Ugo D'Ambrosio
- Institut Botanic de Barcelona (IBB-CSIC, Ajuntament de Barcelona), Passeig del Migdia s/n, 08038, Barcelona, Catalonia, Spain
| | - Hana Malinská
- Institut Botanic de Barcelona (IBB-CSIC, Ajuntament de Barcelona), Passeig del Migdia s/n, 08038, Barcelona, Catalonia, Spain
- Department of Biology, Faculty of Science, Jan Evangelista Purkyně University in Ústí nad Labem, 400 96, Ústí nad Labem, Czech Republic
| | - Vratislav Peska
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65, Brno, Czech Republic
| | - Iván Pérez Lorenzo
- Institut Botanic de Barcelona (IBB-CSIC, Ajuntament de Barcelona), Passeig del Migdia s/n, 08038, Barcelona, Catalonia, Spain
| | - Aleš Kovařík
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65, Brno, Czech Republic
| | - Boris Vyskot
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65, Brno, Czech Republic
| | - Bohuslav Janoušek
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65, Brno, Czech Republic
| | - Sònia Garcia
- Institut Botanic de Barcelona (IBB-CSIC, Ajuntament de Barcelona), Passeig del Migdia s/n, 08038, Barcelona, Catalonia, Spain
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Bačovský V, Čegan R, Šimoníková D, Hřibová E, Hobza R. The Formation of Sex Chromosomes in Silene latifolia and S. dioica Was Accompanied by Multiple Chromosomal Rearrangements. FRONTIERS IN PLANT SCIENCE 2020; 11:205. [PMID: 32180787 PMCID: PMC7059608 DOI: 10.3389/fpls.2020.00205] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 02/11/2020] [Indexed: 05/02/2023]
Abstract
The genus Silene includes a plethora of dioecious and gynodioecious species. Two species, Silene latifolia (white campion) and Silene dioica (red campion), are dioecious plants, having heteromorphic sex chromosomes with an XX/XY sex determination system. The X and Y chromosomes differ mainly in size, DNA content and posttranslational histone modifications. Although it is generally assumed that the sex chromosomes evolved from a single pair of autosomes, it is difficult to distinguish the ancestral pair of chromosomes in related gynodioecious and hermaphroditic plants. We designed an oligo painting probe enriched for X-linked scaffolds from currently available genomic data and used this probe on metaphase chromosomes of S. latifolia (2n = 24, XY), S. dioica (2n = 24, XY), and two gynodioecious species, S. vulgaris (2n = 24) and S. maritima (2n = 24). The X chromosome-specific oligo probe produces a signal specifically on the X and Y chromosomes in S. latifolia and S. dioica, mainly in the subtelomeric regions. Surprisingly, in S. vulgaris and S. maritima, the probe hybridized to three pairs of autosomes labeling their p-arms. This distribution suggests that sex chromosome evolution was accompanied by extensive chromosomal rearrangements in studied dioecious plants.
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Affiliation(s)
- Václav Bačovský
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Brno, Czechia
- *Correspondence: Václav Bačovský,
| | - Radim Čegan
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Brno, Czechia
- Institute of Experimental Botany, Czech Academy of Sciences, Centre of the Region Haná for Biotechnological and Agricultural Research, Olomouc, Czechia
| | - Denisa Šimoníková
- Institute of Experimental Botany, Czech Academy of Sciences, Centre of the Region Haná for Biotechnological and Agricultural Research, Olomouc, Czechia
| | - Eva Hřibová
- Institute of Experimental Botany, Czech Academy of Sciences, Centre of the Region Haná for Biotechnological and Agricultural Research, Olomouc, Czechia
| | - Roman Hobza
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Brno, Czechia
- Institute of Experimental Botany, Czech Academy of Sciences, Centre of the Region Haná for Biotechnological and Agricultural Research, Olomouc, Czechia
- Roman Hobza,
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11
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Vondrak T, Ávila Robledillo L, Novák P, Koblížková A, Neumann P, Macas J. Characterization of repeat arrays in ultra-long nanopore reads reveals frequent origin of satellite DNA from retrotransposon-derived tandem repeats. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:484-500. [PMID: 31559657 PMCID: PMC7004042 DOI: 10.1111/tpj.14546] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/09/2019] [Accepted: 09/12/2019] [Indexed: 05/21/2023]
Abstract
Amplification of monomer sequences into long contiguous arrays is the main feature distinguishing satellite DNA from other tandem repeats, yet it is also the main obstacle in its investigation because these arrays are in principle difficult to assemble. Here we explore an alternative, assembly-free approach that utilizes ultra-long Oxford Nanopore reads to infer the length distribution of satellite repeat arrays, their association with other repeats and the prevailing sequence periodicities. Using the satellite DNA-rich legume plant Lathyrus sativus as a model, we demonstrated this approach by analyzing 11 major satellite repeats using a set of nanopore reads ranging from 30 to over 200 kb in length and representing 0.73× genome coverage. We found surprising differences between the analyzed repeats because only two of them were predominantly organized in long arrays typical for satellite DNA. The remaining nine satellites were found to be derived from short tandem arrays located within LTR-retrotransposons that occasionally expanded in length. While the corresponding LTR-retrotransposons were dispersed across the genome, this array expansion occurred mainly in the primary constrictions of the L. sativus chromosomes, which suggests that these genome regions are favourable for satellite DNA accumulation.
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Affiliation(s)
- Tihana Vondrak
- Biology CentreCzech Academy of SciencesBranišovská 31České BudějoviceCZ‐37005Czech Republic
- Faculty of ScienceUniversity of South BohemiaČeské BudějoviceCzech Republic
| | - Laura Ávila Robledillo
- Biology CentreCzech Academy of SciencesBranišovská 31České BudějoviceCZ‐37005Czech Republic
- Faculty of ScienceUniversity of South BohemiaČeské BudějoviceCzech Republic
| | - Petr Novák
- Biology CentreCzech Academy of SciencesBranišovská 31České BudějoviceCZ‐37005Czech Republic
| | - Andrea Koblížková
- Biology CentreCzech Academy of SciencesBranišovská 31České BudějoviceCZ‐37005Czech Republic
| | - Pavel Neumann
- Biology CentreCzech Academy of SciencesBranišovská 31České BudějoviceCZ‐37005Czech Republic
| | - Jiří Macas
- Biology CentreCzech Academy of SciencesBranišovská 31České BudějoviceCZ‐37005Czech Republic
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Orozco-Arias S, Isaza G, Guyot R. Retrotransposons in Plant Genomes: Structure, Identification, and Classification through Bioinformatics and Machine Learning. Int J Mol Sci 2019; 20:E3837. [PMID: 31390781 PMCID: PMC6696364 DOI: 10.3390/ijms20153837] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 07/31/2019] [Accepted: 08/02/2019] [Indexed: 01/26/2023] Open
Abstract
Transposable elements (TEs) are genomic units able to move within the genome of virtually all organisms. Due to their natural repetitive numbers and their high structural diversity, the identification and classification of TEs remain a challenge in sequenced genomes. Although TEs were initially regarded as "junk DNA", it has been demonstrated that they play key roles in chromosome structures, gene expression, and regulation, as well as adaptation and evolution. A highly reliable annotation of these elements is, therefore, crucial to better understand genome functions and their evolution. To date, much bioinformatics software has been developed to address TE detection and classification processes, but many problematic aspects remain, such as the reliability, precision, and speed of the analyses. Machine learning and deep learning are algorithms that can make automatic predictions and decisions in a wide variety of scientific applications. They have been tested in bioinformatics and, more specifically for TEs, classification with encouraging results. In this review, we will discuss important aspects of TEs, such as their structure, importance in the evolution and architecture of the host, and their current classifications and nomenclatures. We will also address current methods and their limitations in identifying and classifying TEs.
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Affiliation(s)
- Simon Orozco-Arias
- Department of Computer Science, Universidad Autónoma de Manizales, Manizales 170001, Colombia
- Department of Systems and Informatics, Universidad de Caldas, Manizales 170001, Colombia
| | - Gustavo Isaza
- Department of Systems and Informatics, Universidad de Caldas, Manizales 170001, Colombia
| | - Romain Guyot
- Department of Electronics and Automatization, Universidad Autónoma de Manizales, Manizales 170001, Colombia.
- Institut de Recherche pour le Développement, CIRAD, University Montpellier, 34000 Montpellier, France.
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13
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Bačovský V, Houben A, Kumke K, Hobza R. The distribution of epigenetic histone marks differs between the X and Y chromosomes in Silene latifolia. PLANTA 2019; 250:487-494. [PMID: 31069521 DOI: 10.1007/s00425-019-03182-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 05/03/2019] [Indexed: 05/18/2023]
Abstract
Contrasting patterns of histone modifications between the X and Y chromosome in Silene latifolia show euchromatic histone mark depletion on the Y chromosome and indicate hyperactivation of one X chromosome in females. Silene latifolia (white campion) is a dioecious plant with heteromorphic sex chromosomes (24, XX in females and 24, XY in males), and a genetically degenerated Y chromosome that is 1.4 times larger than the X chromosome. Although the two sex chromosomes differ in their DNA content, information about epigenetic histone marks and evidence of their function are scarce. We performed immunolabeling experiments using antibodies specific for active and suppressive histone modifications as well as pericentromere-specific histone modifications. We show that the Y chromosome is partially depleted of histone modifications important for transcriptionally active chromatin, and carries these marks only in the pseudo-autosomal region, but that it is not enriched for suppressive and pericentromere histone marks. We also show that two of the active marks are specifically enriched in one of the X chromosomes in females and in the X chromosome in males. Our data support recent findings that genetic imprinting mediates dosage compensation of sex chromosomes in S. latifolia.
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Affiliation(s)
- Václav Bačovský
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65, Brno, Czech Republic.
| | - Andreas Houben
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Gatersleben, 06466, Germany
| | - Katrin Kumke
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Gatersleben, 06466, Germany
| | - Roman Hobza
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65, Brno, Czech Republic.
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14
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Li SF, Guo YJ, Li JR, Zhang DX, Wang BX, Li N, Deng CL, Gao WJ. The landscape of transposable elements and satellite DNAs in the genome of a dioecious plant spinach ( Spinacia oleracea L.). Mob DNA 2019; 10:3. [PMID: 30675191 PMCID: PMC6337768 DOI: 10.1186/s13100-019-0147-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 01/07/2019] [Indexed: 11/10/2022] Open
Abstract
Background Repetitive sequences, including transposable elements (TEs) and satellite DNAs, occupy a considerable portion of plant genomes. Analysis of the repeat fraction benefits the understanding of genome structure and evolution. Spinach (Spinacia oleracea L.), an important vegetable crop, is also a model dioecious plant species for studying sex determination and sex chromosome evolution. However, the repetitive sequences of the spinach genome have not been fully investigated. Results We extensively analyzed the repetitive components of draft spinach genome, especially TEs and satellites, by different strategies. A total of 16,002 full-length TEs were identified. Among the most abundant long terminal repeat (LTR) retrotransposons (REs), Copia elements were overrepresented compared with Gypsy ones. Angela was the most dominating Copia lineage; Ogre/Tat was the most abundant Gypsy lineage. The mean insertion age of LTR-REs was 1.42 million years; approximately 83.7% of these elements were retrotransposed during the last two million years. RepeatMasker totally masked about 64.05% of the spinach genome, with LTR-REs, non-LTR-REs, and DNA transposons occupying 49.2, 2.4, and 5.6%, respectively. Fluorescence in situ hybridization (FISH) analysis showed that most LTR-REs dispersed all over the chromosomes, by contrast, elements of CRM lineage were distributed at the centromeric region of all chromosomes. In addition, Ogre/Tat lineage mainly accumulated on sex chromosomes, and satellites Spsat2 and Spsat3 were exclusively located at the telomeric region of the short arm of sex chromosomes. Conclusions We reliably annotated the TE fraction of the draft genome of spinach. FISH analysis indicates that Ogre/Tat lineage and the sex chromosome-specific satellites DNAs might participate in sex chromosome formation and evolution. Based on FISH signals of microsatellites, together with 45S rDNA, a fine karyotype of spinach was established. This study improves our knowledge of repetitive sequence organization in spinach genome and aids in accurate spinach karyotype construction. Electronic supplementary material The online version of this article (10.1186/s13100-019-0147-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shu-Fen Li
- 1College of Life Sciences, Henan Normal University, Xinxiang, 453007 China
| | - Yu-Jiao Guo
- 1College of Life Sciences, Henan Normal University, Xinxiang, 453007 China
| | - Jia-Rong Li
- 1College of Life Sciences, Henan Normal University, Xinxiang, 453007 China
| | - Dong-Xu Zhang
- 2College of Life Science, Shanxi Datong University, Datong, 037009 China
| | - Bing-Xiao Wang
- 1College of Life Sciences, Henan Normal University, Xinxiang, 453007 China
| | - Ning Li
- 1College of Life Sciences, Henan Normal University, Xinxiang, 453007 China
| | - Chuan-Liang Deng
- 1College of Life Sciences, Henan Normal University, Xinxiang, 453007 China
| | - Wu-Jun Gao
- 1College of Life Sciences, Henan Normal University, Xinxiang, 453007 China
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Hobza R, Hudzieczek V, Kubat Z, Cegan R, Vyskot B, Kejnovsky E, Janousek B. Sex and the flower - developmental aspects of sex chromosome evolution. ANNALS OF BOTANY 2018; 122:1085-1101. [PMID: 30032185 PMCID: PMC6324748 DOI: 10.1093/aob/mcy130] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 07/13/2018] [Indexed: 05/07/2023]
Abstract
Background The evolution of dioecious plants is occasionally accompanied by the establishment of sex chromosomes: both XY and ZW systems have been found in plants. Structural studies of sex chromosomes are now being followed up by functional studies that are gradually shedding light on the specific genetic and epigenetic processes that shape the development of separate sexes in plants. Scope This review describes sex determination diversity in plants and the genetic background of dioecy, summarizes recent progress in the investigation of both classical and emerging model dioecious plants and discusses novel findings. The advantages of interspecies hybrids in studies focused on sex determination and the role of epigenetic processes in sexual development are also overviewed. Conclusions We integrate the genic, genomic and epigenetic levels of sex determination and stress the impact of sex chromosome evolution on structural and functional aspects of plant sexual development. We also discuss the impact of dioecy and sex chromosomes on genome structure and expression.
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Affiliation(s)
- Roman Hobza
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska, Brno, Czech Republic
| | - Vojtech Hudzieczek
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska, Brno, Czech Republic
| | - Zdenek Kubat
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska, Brno, Czech Republic
| | - Radim Cegan
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska, Brno, Czech Republic
| | - Boris Vyskot
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska, Brno, Czech Republic
| | - Eduard Kejnovsky
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska, Brno, Czech Republic
| | - Bohuslav Janousek
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska, Brno, Czech Republic
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Rodríguez Lorenzo JL, Hobza R, Vyskot B. DNA methylation and genetic degeneration of the Y chromosome in the dioecious plant Silene latifolia. BMC Genomics 2018; 19:540. [PMID: 30012097 PMCID: PMC6048894 DOI: 10.1186/s12864-018-4936-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 07/10/2018] [Indexed: 02/01/2023] Open
Abstract
Background S. latifolia is a model organism for the study of sex chromosome evolution in plants. Its sex chromosomes include large regions in which recombination became gradually suppressed. The regions tend to expand over time resulting in the formation of evolutionary strata. Non-recombination and later accumulation of repetitive sequences is a putative cause of the size increase in the Y chromosome. Gene decay and accumulation of repetitive DNA are identified as key evolutionary events. Transposons in the X and Y chromosomes are distributed differently and there is a regulation of transposon insertion by DNA methylation of the target sequences, this points to an important role of DNA methylation during sex chromosome evolution in Silene latifolia. The aim of this study was to elucidate whether the reduced expression of the Y allele in S. latifolia is caused by genetic degeneration or if the cause is methylation triggered by transposons and repetitive sequences. Results Gene expression analysis in S. latifolia males has shown expression bias in both X and Y alleles. To determine whether these differences are caused by genetic degeneration or methylation spread by transposons and repetitive sequences, we selected several sex-linked genes with varying degrees of degeneration and from different evolutionary strata. Immunoprecipitation of methylated DNA (MeDIP) from promoter, exon and intron regions was used and validated through bisulfite sequencing. We found DNA methylation in males, and only in the promoter of genes of stratum I (older). The Y alleles in genes of stratum I were methylation enriched compared to X alleles. There was also abundant and high percentage methylation in the CHH context in most sequences, indicating de novo methylation through the RdDM pathway. Conclusions We speculate that TE accumulation and not gene decay is the cause of DNA methylation in the S. latifolia Y sex chromosome with influence on the process of heterochromatinization. Electronic supplementary material The online version of this article (10.1186/s12864-018-4936-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- José Luis Rodríguez Lorenzo
- Plant Developmental Genetics, Institute of Biophysics v.v.i, Academy of Sciences of the Czech Republic, Královopolská 135, 612 65, Brno, Czech Republic.
| | - Roman Hobza
- Plant Developmental Genetics, Institute of Biophysics v.v.i, Academy of Sciences of the Czech Republic, Královopolská 135, 612 65, Brno, Czech Republic
| | - Boris Vyskot
- Plant Developmental Genetics, Institute of Biophysics v.v.i, Academy of Sciences of the Czech Republic, Královopolská 135, 612 65, Brno, Czech Republic
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17
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Puterova J, Kubat Z, Kejnovsky E, Jesionek W, Cizkova J, Vyskot B, Hobza R. The slowdown of Y chromosome expansion in dioecious Silene latifolia due to DNA loss and male-specific silencing of retrotransposons. BMC Genomics 2018; 19:153. [PMID: 29458354 PMCID: PMC5819184 DOI: 10.1186/s12864-018-4547-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 02/13/2018] [Indexed: 11/10/2022] Open
Abstract
Background The rise and fall of the Y chromosome was demonstrated in animals but plants often possess the large evolutionarily young Y chromosome that is thought has expanded recently. Break-even points dividing expansion and shrinkage phase of plant Y chromosome evolution are still to be determined. To assess the size dynamics of the Y chromosome, we studied intraspecific genome size variation and genome composition of male and female individuals in a dioecious plant Silene latifolia, a well-established model for sex-chromosomes evolution. Results Our genome size data are the first to demonstrate that regardless of intraspecific genome size variation, Y chromosome has retained its size in S. latifolia. Bioinformatics study of genome composition showed that constancy of Y chromosome size was caused by Y chromosome DNA loss and the female-specific proliferation of recently active dominant retrotransposons. We show that several families of retrotransposons have contributed to genome size variation but not to Y chromosome size change. Conclusions Our results suggest that the large Y chromosome of S. latifolia has slowed down or stopped its expansion. Female-specific proliferation of retrotransposons, enlarging the genome with exception of the Y chromosome, was probably caused by silencing of highly active retrotransposons in males and represents an adaptive mechanism to suppress degenerative processes in the haploid stage. Sex specific silencing of transposons might be widespread in plants but hidden in traditional hermaphroditic model plants. Electronic supplementary material The online version of this article (10.1186/s12864-018-4547-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Janka Puterova
- Department of Plant Developmental Genetics, Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 612 00, Brno, Czech Republic.,Department of Information Systems, Faculty of Information Technology, Brno University of Technology, 61200, Brno, Czech Republic
| | - Zdenek Kubat
- Department of Plant Developmental Genetics, Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 612 00, Brno, Czech Republic.
| | - Eduard Kejnovsky
- Department of Plant Developmental Genetics, Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 612 00, Brno, Czech Republic
| | - Wojciech Jesionek
- Department of Plant Developmental Genetics, Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 612 00, Brno, Czech Republic
| | - Jana Cizkova
- Centre of Plant Structural and Functional Genomics, Institute of Experimental Botany, Czech Academy of Sciences, 783 71, Olomouc - Holice, Czech Republic
| | - Boris Vyskot
- Department of Plant Developmental Genetics, Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 612 00, Brno, Czech Republic
| | - Roman Hobza
- Department of Plant Developmental Genetics, Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 612 00, Brno, Czech Republic. .,Centre of Plant Structural and Functional Genomics, Institute of Experimental Botany, Czech Academy of Sciences, 783 71, Olomouc - Holice, Czech Republic.
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Impact of Repetitive Elements on the Y Chromosome Formation in Plants. Genes (Basel) 2017; 8:genes8110302. [PMID: 29104214 PMCID: PMC5704215 DOI: 10.3390/genes8110302] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 10/19/2017] [Accepted: 10/26/2017] [Indexed: 12/21/2022] Open
Abstract
In contrast to animals, separate sexes and sex chromosomes in plants are very rare. Although the evolution of sex chromosomes has been the subject of numerous studies, the impact of repetitive sequences on sex chromosome architecture is not fully understood. New genomic approaches shed light on the role of satellites and transposable elements in the process of Y chromosome evolution. We discuss the impact of repetitive sequences on the structure and dynamics of sex chromosomes with specific focus on Rumex acetosa and Silene latifolia. Recent papers showed that both the expansion and shrinkage of the Y chromosome is influenced by sex-specific regulation of repetitive DNA spread. We present a view that the dynamics of Y chromosome formation is an interplay of genetic and epigenetic processes.
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19
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Chromosome Evolution in Connection with Repetitive Sequences and Epigenetics in Plants. Genes (Basel) 2017; 8:genes8100290. [PMID: 29064432 PMCID: PMC5664140 DOI: 10.3390/genes8100290] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Revised: 10/16/2017] [Accepted: 10/18/2017] [Indexed: 01/18/2023] Open
Abstract
Chromosome evolution is a fundamental aspect of evolutionary biology. The evolution of chromosome size, structure and shape, number, and the change in DNA composition suggest the high plasticity of nuclear genomes at the chromosomal level. Repetitive DNA sequences, which represent a conspicuous fraction of every eukaryotic genome, particularly in plants, are found to be tightly linked with plant chromosome evolution. Different classes of repetitive sequences have distinct distribution patterns on the chromosomes. Mounting evidence shows that repetitive sequences may play multiple generative roles in shaping the chromosome karyotypes in plants. Furthermore, recent development in our understanding of the repetitive sequences and plant chromosome evolution has elucidated the involvement of a spectrum of epigenetic modification. In this review, we focused on the recent evidence relating to the distribution pattern of repetitive sequences in plant chromosomes and highlighted their potential relevance to chromosome evolution in plants. We also discussed the possible connections between evolution and epigenetic alterations in chromosome structure and repatterning, such as heterochromatin formation, centromere function, and epigenetic-associated transposable element inactivation.
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20
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Puterova J, Razumova O, Martinek T, Alexandrov O, Divashuk M, Kubat Z, Hobza R, Karlov G, Kejnovsky E. Satellite DNA and Transposable Elements in Seabuckthorn (Hippophae rhamnoides), a Dioecious Plant with Small Y and Large X Chromosomes. Genome Biol Evol 2017; 9:197-212. [PMID: 28057732 PMCID: PMC5381607 DOI: 10.1093/gbe/evw303] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/03/2017] [Indexed: 01/05/2023] Open
Abstract
Seabuckthorn (Hippophae rhamnoides) is a dioecious shrub commonly used in the pharmaceutical, cosmetic, and environmental industry as a source of oil, minerals and vitamins. In this study, we analyzed the transposable elements and satellites in its genome. We carried out Illumina DNA sequencing and reconstructed the main repetitive DNA sequences. For data analysis, we developed a new bioinformatics approach for advanced satellite DNA analysis and showed that about 25% of the genome consists of satellite DNA and about 24% is formed of transposable elements, dominated by Ty3/Gypsy and Ty1/Copia LTR retrotransposons. FISH mapping revealed X chromosome-accumulated, Y chromosome-specific or both sex chromosomes-accumulated satellites but most satellites were found on autosomes. Transposable elements were located mostly in the subtelomeres of all chromosomes. The 5S rDNA and 45S rDNA were localized on one autosomal locus each. Although we demonstrated the small size of the Y chromosome of the seabuckthorn and accumulated satellite DNA there, we were unable to estimate the age and extent of the Y chromosome degeneration. Analysis of dioecious relatives such as Shepherdia would shed more light on the evolution of these sex chromosomes.
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Affiliation(s)
- Janka Puterova
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
- Department of Information Systems, Faculty of Information Technology, Brno University of Technology, Brno, Czech Republic
| | - Olga Razumova
- Centre for Molecular Biotechnology, Russian State Agrarian University – Moscow Timiryazev Agricultural Academy, Moscow, Russia
| | - Tomas Martinek
- Department of Information Systems, Faculty of Information Technology, Brno University of Technology, Brno, Czech Republic
| | - Oleg Alexandrov
- Centre for Molecular Biotechnology, Russian State Agrarian University – Moscow Timiryazev Agricultural Academy, Moscow, Russia
| | - Mikhail Divashuk
- Centre for Molecular Biotechnology, Russian State Agrarian University – Moscow Timiryazev Agricultural Academy, Moscow, Russia
| | - Zdenek Kubat
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
| | - Roman Hobza
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
- Institute of Experimental Botany, Center of the Region Haná for Biotechnological and Agricultural Research, Olomouc, Czech Republic
| | - Gennady Karlov
- Centre for Molecular Biotechnology, Russian State Agrarian University – Moscow Timiryazev Agricultural Academy, Moscow, Russia
- All-Russia Research Institute of Agricultural Biotechnology, Moscow, Russia
| | - Eduard Kejnovsky
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
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Abstract
Structurally and functionally diverged sex chromosomes have evolved in many animals as well as in some plants. Sex chromosomes represent a specific genomic region(s) with locally suppressed recombination. As a consequence, repetitive sequences involving transposable elements, tandem repeats (satellites and microsatellites), and organellar DNA accumulate on the Y (W) chromosomes. In this paper, we review the main types of repetitive elements, their gathering on the Y chromosome, and discuss new findings showing that not only accumulation of various repeats in non-recombining regions but also opposite processes form Y chromosome. The aim of this review is also to discuss the mechanisms of repetitive DNA spread involving (retro) transposition, DNA polymerase slippage or unequal crossing-over, as well as modes of repeat removal by ectopic recombination. The intensity of these processes differs in non-recombining region(s) of sex chromosomes when compared to the recombining parts of genome. We also speculate about the relationship between heterochromatinization and the formation of heteromorphic sex chromosomes.
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Li SF, Zhang GJ, Yuan JH, Deng CL, Gao WJ. Repetitive sequences and epigenetic modification: inseparable partners play important roles in the evolution of plant sex chromosomes. PLANTA 2016; 243:1083-95. [PMID: 26919983 DOI: 10.1007/s00425-016-2485-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Accepted: 02/07/2016] [Indexed: 05/03/2023]
Abstract
The present review discusses the roles of repetitive sequences played in plant sex chromosome evolution, and highlights epigenetic modification as potential mechanism of repetitive sequences involved in sex chromosome evolution. Sex determination in plants is mostly based on sex chromosomes. Classic theory proposes that sex chromosomes evolve from a specific pair of autosomes with emergence of a sex-determining gene(s). Subsequently, the newly formed sex chromosomes stop recombination in a small region around the sex-determining locus, and over time, the non-recombining region expands to almost all parts of the sex chromosomes. Accumulation of repetitive sequences, mostly transposable elements and tandem repeats, is a conspicuous feature of the non-recombining region of the Y chromosome, even in primitive one. Repetitive sequences may play multiple roles in sex chromosome evolution, such as triggering heterochromatization and causing recombination suppression, leading to structural and morphological differentiation of sex chromosomes, and promoting Y chromosome degeneration and X chromosome dosage compensation. In this article, we review the current status of this field, and based on preliminary evidence, we posit that repetitive sequences are involved in sex chromosome evolution probably via epigenetic modification, such as DNA and histone methylation, with small interfering RNAs as the mediator.
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Affiliation(s)
- Shu-Fen Li
- College of Life Sciences, Henan Normal University, Xinxiang, 453007, China
| | - Guo-Jun Zhang
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Jin-Hong Yuan
- College of Life Sciences, Henan Normal University, Xinxiang, 453007, China
| | - Chuan-Liang Deng
- College of Life Sciences, Henan Normal University, Xinxiang, 453007, China
| | - Wu-Jun Gao
- College of Life Sciences, Henan Normal University, Xinxiang, 453007, China.
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Kazama Y, Ishii K, Aonuma W, Ikeda T, Kawamoto H, Koizumi A, Filatov DA, Chibalina M, Bergero R, Charlesworth D, Abe T, Kawano S. A new physical mapping approach refines the sex-determining gene positions on the Silene latifolia Y-chromosome. Sci Rep 2016; 6:18917. [PMID: 26742857 PMCID: PMC4705512 DOI: 10.1038/srep18917] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 12/01/2015] [Indexed: 12/14/2022] Open
Abstract
Sex chromosomes are particularly interesting regions of the genome for both molecular genetics and evolutionary studies; yet, for most species, we lack basic information, such as the gene order along the chromosome. Because they lack recombination, Y-linked genes cannot be mapped genetically, leaving physical mapping as the only option for establishing the extent of synteny and homology with the X chromosome. Here, we developed a novel and general method for deletion mapping of non-recombining regions by solving “the travelling salesman problem”, and evaluate its accuracy using simulated datasets. Unlike the existing radiation hybrid approach, this method allows us to combine deletion mutants from different experiments and sources. We applied our method to a set of newly generated deletion mutants in the dioecious plant Silene latifolia and refined the locations of the sex-determining loci on its Y chromosome map.
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Affiliation(s)
- Yusuke Kazama
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Kotaro Ishii
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Wataru Aonuma
- Department of Integrated Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan
| | - Tokihiro Ikeda
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Hiroki Kawamoto
- Department of Integrated Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan
| | - Ayako Koizumi
- Department of Integrated Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan
| | - Dmitry A Filatov
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK
| | - Margarita Chibalina
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK
| | - Roberta Bergero
- Institute of Evolutionary Biology, University of Edinburgh, School of Biological Sciences, Edinburgh EH9 3JT, UK
| | - Deborah Charlesworth
- Institute of Evolutionary Biology, University of Edinburgh, School of Biological Sciences, Edinburgh EH9 3JT, UK
| | - Tomoko Abe
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Shigeyuki Kawano
- Department of Integrated Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan
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Charlesworth D. Plant contributions to our understanding of sex chromosome evolution. THE NEW PHYTOLOGIST 2015; 208:52-65. [PMID: 26053356 DOI: 10.1111/nph.13497] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 05/01/2015] [Indexed: 05/06/2023]
Abstract
A minority of angiosperms have male and female flowers separated in distinct individuals (dioecy), and most dioecious plants do not have cytologically different (heteromorphic) sex chromosomes. Plants nevertheless have several advantages for the study of sex chromosome evolution, as genetic sex determination has evolved repeatedly and is often absent in close relatives. I review sex-determining regions in non-model plant species, which may help us to understand when and how (and, potentially, test hypotheses about why) recombination suppression evolves within young sex chromosomes. I emphasize high-throughput sequencing approaches that are increasingly being applied to plants to test for non-recombining regions. These data are particularly illuminating when combined with sequence data that allow phylogenetic analyses, and estimates of when these regions evolved. Together with comparative genetic mapping, this has revealed that sex-determining loci and sex-linked regions evolved independently in many plant lineages, sometimes in closely related dioecious species, and often within the past few million years. In reviewing recent progress, I suggest areas for future work, such as the use of phylogenies to allow the informed choice of outgroup species suitable for inferring the directions of changes, including testing whether Y chromosome-like regions are undergoing genetic degeneration, a predicted consequence of losing recombination.
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Affiliation(s)
- Deborah Charlesworth
- Institute of Evolutionary Biology, University of Edinburgh, Ashworth Lab, King's Buildings, W. Mains Road, Edinburgh, EH9 3FL, UK
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Vyskot B, Hobza R. The genomics of plant sex chromosomes. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2015; 236:126-35. [PMID: 26025526 DOI: 10.1016/j.plantsci.2015.03.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2014] [Revised: 02/27/2015] [Accepted: 03/26/2015] [Indexed: 05/18/2023]
Abstract
Around six percent of flowering species are dioecious, with separate female and male individuals. Sex determination is mostly based on genetics, but morphologically distinct sex chromosomes have only evolved in a few species. Of these, heteromorphic sex chromosomes have been most clearly described in the two model species - Silene latifolia and Rumex acetosa. In both species, the sex chromosomes are the largest chromosomes in the genome. They are hence easily distinguished, can be physically separated and analyzed. This review discusses some recent experimental data on selected model dioecious species, with a focus on S. latifolia. Phylogenetic analyses show that dioecy in plants originated independently and repeatedly even within individual genera. A cogent question is whether there is genetic degeneration of the non-recombining part of the plant Y chromosome, as in mammals, and, if so, whether reduced levels of gene expression in the heterogametic sex are equalized by dosage compensation. Current data provide no clear conclusion. We speculate that although some transcriptome analyses indicate the first signs of degeneration, especially in S. latifolia, the evolutionary processes forming plant sex chromosomes in plants may, to some extent, differ from those in animals.
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Affiliation(s)
- Boris Vyskot
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, 61265 Brno, Czech Republic.
| | - Roman Hobza
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, 61265 Brno, Czech Republic
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Kovacova V, Zluvova J, Janousek B, Talianova M, Vyskot B. The evolutionary fate of the horizontally transferred agrobacterial mikimopine synthase gene in the genera Nicotiana and Linaria. PLoS One 2014; 9:e113872. [PMID: 25420106 PMCID: PMC4242671 DOI: 10.1371/journal.pone.0113872] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 10/31/2014] [Indexed: 11/19/2022] Open
Abstract
Few cases of spontaneously horizontally transferred bacterial genes into plant genomes have been described to date. The occurrence of horizontally transferred genes from the T-DNA of Agrobacterium rhizogenes into the plant genome has been reported in the genus Nicotiana and in the species Linaria vulgaris. Here we compare patterns of evolution in one of these genes (a gene encoding mikimopine synthase, mis) following three different events of horizontal gene transfer (HGT). As this gene plays an important role in Agrobacterium, and there are known cases showing that genes from pathogens can acquire plant protection function, we hypothesised that in at least some of the studied species we will find signs of selective pressures influencing mis sequence. The mikimopine synthase (mis) gene evolved in a different manner in the branch leading to Nicotiana tabacum and N. tomentosiformis, in the branch leading to N. glauca and in the genus Linaria. Our analyses of the genus Linaria suggest that the mis gene began to degenerate soon after the HGT. In contrast, in the case of N. glauca, the mis gene evolved under significant selective pressures. This suggests a possible role of mikimopine synthase in current N. glauca and its ancestor(s). In N. tabacum and N. tomentosiformis, the mis gene has a common frameshift mutation that disrupted its open reading frame. Interestingly, our results suggest that in spite of the frameshift, the mis gene could evolve under selective pressures. This sequence may still have some regulatory role at the RNA level as suggested by coverage of this sequence by small RNAs in N. tabacum.
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Affiliation(s)
- Viera Kovacova
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, Brno, Czech Republic
| | - Jitka Zluvova
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, Brno, Czech Republic
| | - Bohuslav Janousek
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, Brno, Czech Republic
| | - Martina Talianova
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, Brno, Czech Republic
| | - Boris Vyskot
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, Brno, Czech Republic
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Soukupova M, Nevrtalova E, Cížková J, Vogel I, Cegan R, Hobza R, Vyskot B. The X chromosome is necessary for somatic development in the dioecious Silene latifolia: cytogenetic and molecular evidence and sequencing of a haploid genome. Cytogenet Genome Res 2014; 143:96-103. [PMID: 24993893 DOI: 10.1159/000363431] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Silene latifolia (or white campion) possesses a well-established sex determination system with a dominant Y chromosome in males (the mammalian type). The heteromorphic sex chromosomes X and Y in S. latifolia largely stopped recombination; thus, we can expect a gradual genetic degeneration of the Y chromosome. It is well proven that neither diploid nor polyploid S. latifolia sporophytes can survive without at least one X, so the only life stage possessing the Y as the sole sex chromosome is the male gametophyte (pollen tube), while the female gametophyte seems to be X-dependent. Previous studies on anther-derived plants of this species showed that the obtained plants (largely haploid or dihaploid) were phenotypically and cytologically female. In this paper, we provide molecular evidence for the inviability of plants lacking the X chromosome. Using sex-specific PCR primers, we show that all plantlets and plants derived from anther cultures are female. In studying anther-derived diploid females by sequencing of X-linked markers, we demonstrate that these plants are really homozygous dihaploids. A haploid regenerant plant was sequenced (8× genome coverage) using Illumina technology. Genome data are disposable in the EMBL database as a standard for full genome and X chromosome assembly in this model species. Homozygous dihaploids were back-crossed with males to yield a progeny useful for the study of the evolution of the Y chromosome.
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Affiliation(s)
- Magda Soukupova
- Department of Plant Developmental Genetics, Institute of Biophysics ASCR, Brno, Czech Republic
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Kralova T, Cegan R, Kubat Z, Vrana J, Vyskot B, Vogel I, Kejnovsky E, Hobza R. Identification of a novel retrotransposon with sex chromosome-specific distribution in Silene latifolia. Cytogenet Genome Res 2014; 143:87-95. [PMID: 24751661 DOI: 10.1159/000362142] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Silene latifolia is a dioecious plant species with chromosomal sex determination. Although the evolution of sex chromosomes in S. latifolia has been the subject of numerous studies, a global view of X chromosome structure in this species is still missing. Here, we combine X chromosome microdissection and BAC library screening to isolate new X chromosome-linked sequences. Out of 8 identified BAC clones, only BAC 86M14 showed an X-preferential signal after FISH experiments. Further analysis revealed the existence of the Athila retroelement which is enriched in the X chromosome and nearly absent in the Y chromosome. Based on previous data, the Athila retroelement belongs to the CL3 group of most repetitive sequences in the S. latifolia genome. Structural, transcriptomics and phylogenetic analyses revealed that Athila CL3 represents an old clade in the Athila lineage. We propose a mechanism responsible for Athila CL3 distribution in the S. latifolia genome.
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Affiliation(s)
- Tereza Kralova
- Department of Plant Developmental Genetics, Institute of Biophysics ASCR, Brno, Czech Republic
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