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Cuadrado Á, Montiel EE, Mora P, Figueroa RI, Lorite P, de Bustos A. Contribution of the satellitome to the exceptionally large genome of dinoflagellates: The case of the harmful alga Alexandrium minutum. HARMFUL ALGAE 2023; 130:102543. [PMID: 38061820 DOI: 10.1016/j.hal.2023.102543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 10/30/2023] [Accepted: 11/11/2023] [Indexed: 12/18/2023]
Abstract
Dinoflagellates are known to possess an exceptionally large genome organized in permanently condensed chromosomes. Focusing on the contribution of satellite DNA (satDNA) to the whole DNA content of genomes and its potential role in the architecture of the chromosomes, we present the characterization of the satellitome of Alexandriun minutum strain VGO577. To achieve this, we analyzed Illumina reads using graph-based clustering and performed complementary bioinformatic analyses. In this way, we discovered 180 satDNAs occupying 17.38 % of the genome. The 12 most abundant satDNAs represent the half of the satellitome but no satDNA is overrepresented, with the most abundant contributing ∼1.56 % of the genome. The largest repeat unit is 517 bp long but more than the half of the satDNAs (101) have repeat units shorter than 20 bp. We used FISH to map a selected set of 26 satDNAs. Although some satDNAs generate discrete hybridization signals at specific chromosomal locations (hybridization sites, HS), our cytological analysis showed that most satDNAs are dispersed throughout the genome, probably forming short arrays. Two satDNAs co-localize with the 45S rDNA. With the exception of telomeric DNA, no other satDNA yields HS on all chromosomes. In addition, we analyzed nine satDNAs yielding HS in VGO577 in four other A. minutum strains. Polymorphism at the intraspecific level was found for the presence/absence and/or abundance of some satDNAs, suggesting the amplification/deletion of these satDNAs following geographic separation or during culture maintenance of the strains. We also discuss how these results contribute to the understanding of chromosome architecture and evolution of dinoflagellate genomes.
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Affiliation(s)
- Ángeles Cuadrado
- Department of Biomedicine and Biotecnology, Universidad de Alcalá (UAH), Alcalá de Henares, Madrid 28805, Spain.
| | - Eugenia E Montiel
- Department of Experimental Biology (Genetics Area), Human and Animal Molecular Genetic Group (RNM-924), Universidad de Jaén, Jaén 23071, Spain; Departamento de Biología (Genética), Universidad Autonoma de Madrid, Madrid 28049, Spain
| | - Pablo Mora
- Department of Experimental Biology (Genetics Area), Human and Animal Molecular Genetic Group (RNM-924), Universidad de Jaén, Jaén 23071, Spain
| | - Rosa I Figueroa
- Centro Oceanográfico de Vigo, Instituto Español de Oceanografía (IEO-CSIC), Subida a Radio Faro 50, Vigo 36390, Spain
| | - Pedro Lorite
- Department of Experimental Biology (Genetics Area), Human and Animal Molecular Genetic Group (RNM-924), Universidad de Jaén, Jaén 23071, Spain
| | - Alfredo de Bustos
- Department of Biomedicine and Biotecnology, Universidad de Alcalá (UAH), Alcalá de Henares, Madrid 28805, Spain
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2
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Ferraz ME, Ribeiro T, Sader M, Nascimento T, Pedrosa-Harand A. Comparative analysis of repetitive DNA in dysploid and non-dysploid Phaseolus beans. Chromosome Res 2023; 31:30. [PMID: 37812264 DOI: 10.1007/s10577-023-09739-3] [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: 07/11/2023] [Revised: 08/31/2023] [Accepted: 09/15/2023] [Indexed: 10/10/2023]
Abstract
Structural karyotype changes result from ectopic recombination events frequently associated with repetitive DNA. Although most Phaseolus species present relatively stable karyotypes with 2n = 22 chromosomes, the karyotypes of species of the Leptostachyus group show high rates of structural rearrangements, including a nested chromosome fusion that led to the dysploid chromosome number of the group (2n = 20). We examined the roles of repetitive landscapes in the rearrangements of species of the Leptostachyus group using genome-skimming data to characterize the repeatome in a range of Phaseolus species and compared them to species of that group (P. leptostachyus and P. macvaughii). LTR retrotransposons, especially the Ty3/gypsy lineage Chromovirus, were the most abundant elements in the genomes. Differences in the abundance of Tekay, Retand, and SIRE elements between P. macvaughii and P. leptostachyus were reflected in their total amounts of Ty3/gypsy and Ty1/copia. The satellite DNA fraction was the most divergent among the species, varying both in abundance and distribution, even between P. leptostachyus and P. macvaughii. The rapid turnover of repeats in the Leptostachyus group may be associated with the several rearrangements observed.
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Affiliation(s)
- Maria Eduarda Ferraz
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Biosciences Centre, Federal University of Pernambuco, Recife, PE, Brazil
| | - Tiago Ribeiro
- Integrative Plant Research Lab, Department of Botany and Ecology, Institute of Biosciences, Federal University of Mato Grosso, Cuiabá, MT, Brazil
| | - Mariela Sader
- Multidisciplinary Institute of Plant Biology, National Council for Scientific and Technical Research, National University of Córdoba, Córdoba, Argentina
| | - Thiago Nascimento
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Biosciences Centre, Federal University of Pernambuco, Recife, PE, Brazil
| | - Andrea Pedrosa-Harand
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Biosciences Centre, Federal University of Pernambuco, Recife, PE, Brazil.
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Gorbenko IV, Petrushin IS, Shcherban AB, Orlov YL, Konstantinov YM. Short Interrupted Repeat Cassette (SIRC)-Novel Type of Repetitive DNA Element Found in Arabidopsis thaliana. Int J Mol Sci 2023; 24:11116. [PMID: 37446293 DOI: 10.3390/ijms241311116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/01/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023] Open
Abstract
Short interrupted repeat cassette (SIRC)-a novel DNA element found throughout the A. thaliana nuclear genome. SIRCs are represented by short direct repeats interrupted by diverse DNA sequences. The maxima of SIRC's distribution are located within pericentromeric regions. We suggest that originally SIRC was a special case of the complex internal structure of the miniature inverted repeat transposable element (MITE), and further MITE amplification, transposition, and loss of terminal inverted repeats gave rise to SIRC as an independent DNA element. SIRC sites were significantly enriched with several histone modifications associated with constitutive heterochromatin and mobile genetic elements. The majority of DNA-binding proteins, strongly associated with SIRC, are related to histone modifications for transcription repression. A part of SIRC was found to overlap highly inducible protein-coding genes, suggesting a possible regulatory role for these elements, yet their definitive functions need further investigation.
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Affiliation(s)
- Igor V Gorbenko
- Cell Biology and Bioengineering, Siberian Institute of Plant Physiology and Biochemistry SB RAS, Irkutsk 664033, Russia
| | - Ivan S Petrushin
- Cell Biology and Bioengineering, Siberian Institute of Plant Physiology and Biochemistry SB RAS, Irkutsk 664033, Russia
- Department of Business Communications and Informatics, Irkutsk State University, Irkutsk 664033, Russia
| | - Andrey B Shcherban
- Institute of Cytology and Genetics SB RAS, Novosibirsk 630090, Russia
- Kurchatov Genomic Center ICG SB RAS, Novosibirsk 630090, Russia
| | - Yuriy L Orlov
- The Digital Health Institute, I.M. Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation (Sechenov University), Moscow 119991, Russia
- Agrarian and Technological Institute, Peoples' Friendship University of Russia, Moscow 117198, Russia
| | - Yuri M Konstantinov
- Cell Biology and Bioengineering, Siberian Institute of Plant Physiology and Biochemistry SB RAS, Irkutsk 664033, Russia
- Biosoil Department, Irkutsk State University, Irkutsk 664003, Russia
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4
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Sammarco I, Pieters J, Salony S, Toman I, Zolotarov G, Lafon Placette C. Epigenetic targeting of transposon relics: beating the dead horses of the genome? Epigenetics 2022; 17:1331-1344. [PMID: 36255200 PMCID: PMC9586680 DOI: 10.1080/15592294.2021.2022066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Transposable elements (TEs) have been seen as selfish genetic elements that can propagate in a host genome. Their propagation success is however hindered by a combination of mechanisms such as mutations, selection, and their epigenetic silencing by the host genome. As a result, most copies of TEs in a given genome are dead relics: their sequence is too degenerated to allow any transposition. Nevertheless, these TE relics often, but not always, remain epigenetically silenced, and if not to prevent transposition anymore, one can wonder the reason for this phenomenon. The mere self-perpetuating loop inherent to epigenetic silencing could alone explain that even when inactive, TE copies remain silenced. Beyond this process, nevertheless, antagonistic selective forces are likely to act on TE relic silencing. Especially, without the benefit of preventing transposition, TE relic silencing may prove deleterious to the host fitness, suggesting that the maintenance of TE relic silencing is the result of a fine, and perhaps case-by-case, evolutionary trade-off between beneficial and deleterious effects. Ultimately, the release of TE relics silencing may provide a 'safe' ground for adaptive epimutations to arise. In this review, we provide an overview of these questions in both plants and animals.
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Affiliation(s)
- Iris Sammarco
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic,Institute of Botany, Czech Academy of Sciences, Pruhonice, Czech Republic
| | - Janto Pieters
- Laboratory of Pollen Biology, Institute of Experimental Botany, Czech Academy of Science, Prague, Czech Republic,Department of Plant Experimental Biology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Susnata Salony
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
| | - Izabela Toman
- Department of Anthropology and Human Genetics, Faculty of Science, Charles University, Prague, Czech Republic
| | - Grygoriy Zolotarov
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Clément Lafon Placette
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic,CONTACT Clément Lafon Placette Department of Botany, Faculty of Science, Charles University, PragueCZ-128 01, Czech Republic
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Orooji F, Mirzaghaderi G, Kuo YT, Fuchs J. Variation in the Number and Position of rDNA Loci Contributes to the Diversification and Speciation in Nigella (Ranunculaceae). FRONTIERS IN PLANT SCIENCE 2022; 13:917310. [PMID: 35812971 PMCID: PMC9261981 DOI: 10.3389/fpls.2022.917310] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 05/16/2022] [Indexed: 06/15/2023]
Abstract
Nigella is a small genus belonging to the Ranunculaceae family which is presumably originated and distributed in Aegean and the adjacent Western-Irano-Turanian region. Comparative repeat analysis of N. sativa, N. damascena and N. bucharica was performed using low-pass Illumina genomic reads followed by karyotyping and FISH mapping of seven Nigella species using the in silico identified repeats and ribosomal DNA (rDNA) probes. High- and moderate-copy repeat sequences occupy 57.52, 59.01, and 64.73% of N. sativa, N. damascena and N. bucharica genomes, respectively. Roughly, half of the genomes are retrotransposons (class I transposons), while DNA transposons (class II transposons) contributed to only about 2% of the genomes. The analyzed Nigella species possess large genomes of about 7.4 to 12.4 Gbp/1C. Only two satellite repeats in N. sativa, one in N. damascena and four in N. bucharica were identified, which were mostly (peri)centromeric and represented about 1% of each genome. A high variation in number and position of 45S rDNA loci were found among Nigella species. Interestingly, in N. hispanica, each chromosome revealed at least one 45S rDNA site and one of them occurs in hemizygous condition. Based on the chromosome numbers, genome size and (peri)centromeric satellites, three karyotype groups were observed: Two with 2n = 2x = 12 and a karyotype formula of 10m + 2t (including N. sativa, N. arvensis, N. hispanica as the first group and N. damascena and N. orientalis as the second group) and a more distant group with 2n = 2x = 14 and a karyotype formula of 8m + 2st + 4t (including N. integrifolia and N. bucharica). These karyotype groups agreed with the phylogenetic analysis using ITS and rbcL sequences. We conclude that variation in (peri)centromeric sequences, number and localization of rDNA sites as well as chromosome number (dysploidy) are involved in the diversification of the genus Nigella.
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Affiliation(s)
- Fatemeh Orooji
- Department of Agronomy and Plant Breeding, Faculty of Agriculture, University of Kurdistan, Sanandaj, Iran
| | - Ghader Mirzaghaderi
- Department of Agronomy and Plant Breeding, Faculty of Agriculture, University of Kurdistan, Sanandaj, Iran
| | - Yi-Tzu Kuo
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Jörg Fuchs
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
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6
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Feng L, Wang J, Mao M, Yang W, Adje MO, Xue Y, Zhou X, Zhang H, Luo J, Tang R, Tan L, Lin D, Zhang X, Zang Y, He Y, Chen C, Luan A, Lin W, Xu W, Li X, Sun L, Jiang F, Ma J. The highly continuous reference genome of a leaf-chimeric red pineapple (Ananas comosus var. bracteatus f. tricolor) provides insights into elaboration of leaf color. G3 (BETHESDA, MD.) 2022; 12:jkab452. [PMID: 35100332 PMCID: PMC8824783 DOI: 10.1093/g3journal/jkab452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 12/24/2021] [Indexed: 06/14/2023]
Abstract
Ananas comosus var. bracteatus f. tricolor (GL1) is a red pineapple accession whose mostly green leaves with chimeric white leaf margins turn red in spring and autumn and during flowering. It is an important ornamental plant and ideal plant research model for anthocyanin metabolism, chimeric leaf development, and photosynthesis. Here, we generated a highly contiguous chromosome-scale genome assembly for GL1 and compared it with other 3 published pineapple assemblies (var. comosus accessions MD2 and F153, and var. bracteatus accession CB5). The GL1 assembly has a total size of ∼461 Mb, with a contig N50 of ∼2.97 Mb and Benchmarking Universal Single-Copy Ortholog score of 97.3%. More than 99% of the contigs are anchored to 25 pseudochromosomes. Compared with the other 3 published pineapple assemblies, the GL1 assembly was confirmed to be more continuous. Our evolutionary analysis showed that the Bromeliaceae and Poaceae diverged from their nearest common ancestor ∼82.36 million years ago (MYA). Population structure analysis showed that while GL1 has not undergone admixture, bracteatus accession CB5 has resulted from admixture of 3 species of Ananas. Through classification of orthogroups, analysis of genes under positive selection, and analysis of presence/absence variants, we identified a series of genes related to anthocyanin metabolism and development of chimeric leaves. The structure and evolution of these genes were compared among the published pineapple assemblies with reveal candidate genes for these traits. The GL1 genome assembly and its comparisons with other 3 pineapple genome assemblies provide a valuable resource for the genetic improvement of pineapple and serve as a model for understanding the genomic basis of important traits in different pineapple varieties and other pan-cereal crops.
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Affiliation(s)
- Lijun Feng
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Juntao Wang
- College of Horticulture, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Meiqin Mao
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Wei Yang
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Mark Owusu Adje
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Yanbin Xue
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Xuzixin Zhou
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Huiling Zhang
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Jiaheng Luo
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Ruimin Tang
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Lin Tan
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Dongpu Lin
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Xiaopeng Zhang
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Yaoqiang Zang
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Yehua He
- College of Horticulture, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Changming Chen
- College of Horticulture, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Aiping Luan
- Tropical Crops Genetic Resources Institute of Chinese Academy of Tropical Agricultural Science, Haikou, Hainan 571101, China
| | - Wenqiu Lin
- South Subtropical Crop Research Institute, China Academy of Tropical Agricultural Sciences, Zhanjiang, Guangdong 524000, China
| | - Wentian Xu
- South Subtropical Crop Research Institute, China Academy of Tropical Agricultural Sciences, Zhanjiang, Guangdong 524000, China
| | - Xi Li
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Lingxia Sun
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Fuxing Jiang
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Jun Ma
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
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7
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Heitkam T, Schulte L, Weber B, Liedtke S, Breitenbach S, Kögler A, Morgenstern K, Brückner M, Tröber U, Wolf H, Krabel D, Schmidt T. Comparative Repeat Profiling of Two Closely Related Conifers ( Larix decidua and Larix kaempferi) Reveals High Genome Similarity With Only Few Fast-Evolving Satellite DNAs. Front Genet 2021; 12:683668. [PMID: 34322154 PMCID: PMC8312256 DOI: 10.3389/fgene.2021.683668] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Accepted: 05/25/2021] [Indexed: 12/26/2022] Open
Abstract
In eukaryotic genomes, cycles of repeat expansion and removal lead to large-scale genomic changes and propel organisms forward in evolution. However, in conifers, active repeat removal is thought to be limited, leading to expansions of their genomes, mostly exceeding 10 giga base pairs. As a result, conifer genomes are largely littered with fragmented and decayed repeats. Here, we aim to investigate how the repeat landscapes of two related conifers have diverged, given the conifers' accumulative genome evolution mode. For this, we applied low-coverage sequencing and read clustering to the genomes of European and Japanese larch, Larix decidua (Lamb.) Carrière and Larix kaempferi (Mill.), that arose from a common ancestor, but are now geographically isolated. We found that both Larix species harbored largely similar repeat landscapes, especially regarding the transposable element content. To pin down possible genomic changes, we focused on the repeat class with the fastest sequence turnover: satellite DNAs (satDNAs). Using comparative bioinformatics, Southern, and fluorescent in situ hybridization, we reveal the satDNAs' organizational patterns, their abundances, and chromosomal locations. Four out of the five identified satDNAs are widespread in the Larix genus, with two even present in the more distantly related Pseudotsuga and Abies genera. Unexpectedly, the EulaSat3 family was restricted to L. decidua and absent from L. kaempferi, indicating its evolutionarily young age. Taken together, our results exemplify how the accumulative genome evolution of conifers may limit the overall divergence of repeats after speciation, producing only few repeat-induced genomic novelties.
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Affiliation(s)
- Tony Heitkam
- Institute of Botany, Technische Universität Dresden, Dresden, Germany
| | - Luise Schulte
- Institute of Botany, Technische Universität Dresden, Dresden, Germany.,Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Beatrice Weber
- Institute of Botany, Technische Universität Dresden, Dresden, Germany
| | - Susan Liedtke
- Institute of Botany, Technische Universität Dresden, Dresden, Germany
| | - Sarah Breitenbach
- Institute of Botany, Technische Universität Dresden, Dresden, Germany
| | - Anja Kögler
- Institute of Botany, Technische Universität Dresden, Dresden, Germany
| | - Kristin Morgenstern
- Institute of Forest Botany and Forest Zoology, Technische Universität Dresden, Tharandt, Germany
| | | | - Ute Tröber
- Staatsbetrieb Sachsenforst, Pirna, Germany
| | - Heino Wolf
- Staatsbetrieb Sachsenforst, Pirna, Germany
| | - Doris Krabel
- Institute of Forest Botany and Forest Zoology, Technische Universität Dresden, Tharandt, Germany
| | - Thomas Schmidt
- Institute of Botany, Technische Universität Dresden, Dresden, Germany
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Li P, Su T, Zhao X, Wang W, Zhang D, Yu Y, Bayer PE, Edwards D, Yu S, Zhang F. Assembly of the non-heading pak choi genome and comparison with the genomes of heading Chinese cabbage and the oilseed yellow sarson. PLANT BIOTECHNOLOGY JOURNAL 2021; 19:966-976. [PMID: 33283404 PMCID: PMC8131043 DOI: 10.1111/pbi.13522] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 11/11/2020] [Accepted: 12/01/2020] [Indexed: 05/10/2023]
Abstract
Brassica rapa displays a wide range of morphological diversity which is exploited for a variety of food crops. Here we present a high-quality genome assembly for pak choi (Brassica rapa L. subsp. chinensis), an important non-heading leafy vegetable, and comparison with the genomes of heading type Chinese cabbage and the oilseed form, yellow sarson. Gene presence-absence variation (PAV) and genomic structural variations (SV) were identified, together with single nucleotide polymorphisms (SNPs). The structure and expression of genes for leaf morphology and flowering were compared between the three morphotypes revealing candidate genes for these traits in B. rapa. The pak choi genome assembly and its comparison with other B. rapa genome assemblies provides a valuable resource for the genetic improvement of this important vegetable crop and as a model to understand the diversity of morphological variation across Brassica species.
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Affiliation(s)
- Peirong Li
- Beijing Vegetable Research Center (BVRC)Beijing Academy of Agriculture and Forestry Sciences (BAAFS)BeijingChina
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China)Ministry of AgricultureBeijingChina
- Beijing Key Laboratory of Vegetable Germplasm ImprovementBeijingChina
| | - Tongbing Su
- Beijing Vegetable Research Center (BVRC)Beijing Academy of Agriculture and Forestry Sciences (BAAFS)BeijingChina
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China)Ministry of AgricultureBeijingChina
- Beijing Key Laboratory of Vegetable Germplasm ImprovementBeijingChina
| | - Xiuyun Zhao
- Beijing Vegetable Research Center (BVRC)Beijing Academy of Agriculture and Forestry Sciences (BAAFS)BeijingChina
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China)Ministry of AgricultureBeijingChina
- Beijing Key Laboratory of Vegetable Germplasm ImprovementBeijingChina
| | - Weihong Wang
- Beijing Vegetable Research Center (BVRC)Beijing Academy of Agriculture and Forestry Sciences (BAAFS)BeijingChina
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China)Ministry of AgricultureBeijingChina
- Beijing Key Laboratory of Vegetable Germplasm ImprovementBeijingChina
| | - Deshuang Zhang
- Beijing Vegetable Research Center (BVRC)Beijing Academy of Agriculture and Forestry Sciences (BAAFS)BeijingChina
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China)Ministry of AgricultureBeijingChina
- Beijing Key Laboratory of Vegetable Germplasm ImprovementBeijingChina
| | - Yangjun Yu
- Beijing Vegetable Research Center (BVRC)Beijing Academy of Agriculture and Forestry Sciences (BAAFS)BeijingChina
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China)Ministry of AgricultureBeijingChina
- Beijing Key Laboratory of Vegetable Germplasm ImprovementBeijingChina
| | - Philipp E. Bayer
- School of Biological Sciences and Institute of AgricultureUniversity of Western AustraliaPerthWAAustralia
| | - David Edwards
- School of Biological Sciences and Institute of AgricultureUniversity of Western AustraliaPerthWAAustralia
| | - Shuancang Yu
- Beijing Vegetable Research Center (BVRC)Beijing Academy of Agriculture and Forestry Sciences (BAAFS)BeijingChina
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China)Ministry of AgricultureBeijingChina
- Beijing Key Laboratory of Vegetable Germplasm ImprovementBeijingChina
| | - Fenglan Zhang
- Beijing Vegetable Research Center (BVRC)Beijing Academy of Agriculture and Forestry Sciences (BAAFS)BeijingChina
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China)Ministry of AgricultureBeijingChina
- Beijing Key Laboratory of Vegetable Germplasm ImprovementBeijingChina
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9
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Sader M, Vaio M, Cauz-Santos LA, Dornelas MC, Vieira MLC, Melo N, Pedrosa-Harand A. Large vs small genomes in Passiflora: the influence of the mobilome and the satellitome. PLANTA 2021; 253:86. [PMID: 33792791 DOI: 10.1007/s00425-021-03598-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 03/18/2021] [Indexed: 05/22/2023]
Abstract
While two lineages of retrotransposons were more abundant in larger Passiflora genomes, the satellitome was more diverse and abundant in the smallest genome analysed. Repetitive sequences are ubiquitous and fast-evolving elements responsible for size variation and large-scale organization of plant genomes. Within Passiflora genus, a tenfold variation in genome size, not attributed to polyploidy, is known. Here, we applied a combined in silico and cytological approach to study the organization and diversification of repetitive elements in three species of this genus representing its known range in genome size variation. Sequences were classified in terms of type and repetitiveness and the most abundant were mapped to chromosomes. We identified long terminal repeat (LTR) retrotransposons as the most abundant elements in the three genomes, showing a considerable variation among species. Satellite DNAs (satDNAs) were less representative, but highly diverse between subgenera. Our results clearly confirm that the largest genome species (Passiflora quadrangularis) presents a higher accumulation of repetitive DNA sequences, specially Angela and Tekay elements, making up most of its genome. Passiflora cincinnata, with intermediate genome and from the same subgenus, showed similarity with P. quadrangularis regarding the families of repetitive DNA sequences, but in different proportions. On the other hand, Passiflora organensis, the smallest genome, from a different subgenus, presented greater diversity and the highest proportion of satDNA. Altogether, our data indicates that while large genomes evolved by an accumulation of retrotransposons, the smallest genome known for the genus has evolved by diversification of different repeat types, particularly satDNAs.
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Affiliation(s)
- Mariela Sader
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Federal University of Pernambuco, Recife, Pernambuco, Brazil.
| | - Magdalena Vaio
- Laboratory of Plant Genome Evolution and Domestication, Department of Plant Biology, Faculty of Agronomy, University of the Republic, Montevideo, Uruguay
| | - Luiz Augusto Cauz-Santos
- Genetics Department, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, São Paulo, Brazil
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | | | - Maria Lucia Carneiro Vieira
- Genetics Department, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, São Paulo, Brazil
| | - Natoniel Melo
- Laboratory of Biotechnology, Embrapa Semiarid, Petrolina, Pernambuco, Brazil
| | - Andrea Pedrosa-Harand
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Federal University of Pernambuco, Recife, Pernambuco, Brazil
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10
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Zhang SJ, Liu L, Yang R, Wang X. Genome Size Evolution Mediated by Gypsy Retrotransposons in Brassicaceae. GENOMICS PROTEOMICS & BIOINFORMATICS 2020; 18:321-332. [PMID: 33137519 PMCID: PMC7801240 DOI: 10.1016/j.gpb.2018.07.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 05/31/2018] [Accepted: 07/16/2018] [Indexed: 12/29/2022]
Abstract
The dynamic activity of transposable elements (TEs) contributes to the vast diversity of genome size and architecture among plants. Here, we examined the genomic distribution and transposition activity of long terminal repeat retrotransposons (LTR-RTs) in Arabidopsis thaliana (Ath) and three of its relatives, Arabidopsis lyrata (Aly), Eutrema salsugineum (Esa), and Schrenkiella parvula (Spa), in Brassicaceae. Our analyses revealed the distinct evolutionary dynamics of Gypsyretrotransposons, which reflects the different patterns of genome size changes of the four species over the past million years. The rate of Gypsy transposition in Aly is approximately five times more rapid than that of Ath and Esa, suggesting an expanding Aly genome. Gypsy insertions in Esa are strictly confined to pericentromeric heterochromatin and associated with dramatic centromere expansion. In contrast, Gypsy insertions in Spa have been largely suppressed over the last million years, likely as a result of a combination of an inherent molecular mechanism of preferential DNA removal and purifying selection at Gypsy elements. Additionally, species-specific clades of Gypsy elements shaped the distinct genome architectures of Aly and Esa.
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Affiliation(s)
- Shi-Jian Zhang
- Department of Crop Genomics and Bioinformatics, College of Agronomy and Biotechnology, National Maize Improvement Center of China, China Agricultural University, Beijing 100094, China
| | - Lei Liu
- Beijing Key Laboratory of Plant Resources Research and Development, School of Sciences, Beijing Technology and Business University, Beijing 100048, China
| | - Ruolin Yang
- College of Life Sciences, Northwest A&F University, Yangling 712100, China.
| | - Xiangfeng Wang
- Department of Crop Genomics and Bioinformatics, College of Agronomy and Biotechnology, National Maize Improvement Center of China, China Agricultural University, Beijing 100094, China.
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11
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Mata-Sucre Y, Sader M, Van-Lume B, Gagnon E, Pedrosa-Harand A, Leitch IJ, Lewis GP, Souza G. How diverse is heterochromatin in the Caesalpinia group? Cytogenomic characterization of Erythrostemon hughesii Gagnon & G.P. Lewis (Leguminosae: Caesalpinioideae). PLANTA 2020; 252:49. [PMID: 32918627 DOI: 10.1007/s00425-020-03453-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 08/27/2020] [Indexed: 05/25/2023]
Abstract
Cytogenomic characterization of Erythrostemon hughesii reveals a heterogeneity of repeats in its subtelomeric heterochromatin. Comparative analyses with other Caesalpinia group species reveal a significant reduction in the abundance of Ty3-gypsy/Chromovirus Tekay retrotransposons during its evolution. In numerically stable karyotypes, repetitive DNA variability is one of the main causes of genome and chromosome variation and evolution. Species from the Caesalpinia group (Leguminosae) are karyotypically characterized by 2n = 24, with small chromosomes and highly variable CMA+ heterochromatin banding patterns that correlate with environmental variables. Erythrostemon hughesii differs from other species of the group examined to date for having subtelomeric CMA+ bands; this contrasts with most species in the group which have proximal bands. Here we analyse the repeatome of E. hughesii using genome skimming and chromosomal mapping approaches to characterize the identity of the most abundant repetitive elements and their physical location. The repetitive fraction of E. hughesii comprises 28.73% of the genome. The most abundant elements were retrotransposons (RT) with long terminal repeats (LTR-RT; 9.76%) and satellite DNAs (7.83%). Within the LTR-RTs, the most abundant lineages were: Ty1/copia-Ale (1%), Ty3/gypsy CRM (0.88%) and Ty3/gypsy Athila (0.75%). Using fluorescent in situ hybridization four satellite DNAs and several LTR-RT elements were shown to be present in most subtelomeric CMA+ bands. These results highlight how the repeatome in E. hughesii, a species from Oaxaca state in Mexico, is clearly distinct from Northeast Brazilian species of the Caesalpinia group, mainly due to its high diversity of repeats in its subtelomeric heterochromatic bands and low amount of LTR-RT Ty3/gypsy-Tekay elements. Comparative sequence analysis of Tekay elements from different species is congruent with a clade-specific origin of this LTR-RT after the divergence of the Caesalpinia group. We hypothesize that repeat-rich heterochromatin may play a role in leading to faster genomic divergence between individuals, increasing speciation and diversification.
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Affiliation(s)
- Yennifer Mata-Sucre
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Federal University of Pernambuco, Rua Nelson Chaves S/N, Cidade Universitaria, Recife, PE, 50670-420, Brazil
| | - Mariela Sader
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Federal University of Pernambuco, Rua Nelson Chaves S/N, Cidade Universitaria, Recife, PE, 50670-420, Brazil
| | - Brena Van-Lume
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Federal University of Pernambuco, Rua Nelson Chaves S/N, Cidade Universitaria, Recife, PE, 50670-420, Brazil
| | - Edeline Gagnon
- Royal Botanic Garden Edinburgh, 20A Inverleith Row, Edinburgh, EH3 5NZ, UK
| | - Andrea Pedrosa-Harand
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Federal University of Pernambuco, Rua Nelson Chaves S/N, Cidade Universitaria, Recife, PE, 50670-420, Brazil
| | - Ilia J Leitch
- Comparative Plant and Fungal Biology Department, Royal Botanic Gardens, Kew, Richmond, TW9 3AB, Surrey, UK
| | - Gwilym P Lewis
- Comparative Plant and Fungal Biology Department, Royal Botanic Gardens, Kew, Richmond, TW9 3AB, Surrey, UK
| | - Gustavo Souza
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Federal University of Pernambuco, Rua Nelson Chaves S/N, Cidade Universitaria, Recife, PE, 50670-420, Brazil.
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12
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Quesneville H. Twenty years of transposable element analysis in the Arabidopsis thaliana genome. Mob DNA 2020; 11:28. [PMID: 32742313 PMCID: PMC7385966 DOI: 10.1186/s13100-020-00223-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 07/16/2020] [Indexed: 11/10/2022] Open
Abstract
Transposable elements (TEs) are mobile repetitive DNA sequences shown to be major drivers of genome evolution. As the first plant to have its genome sequenced and analyzed at the genomic scale, Arabidopsis thaliana has largely contributed to our TE knowledge. The present report describes 20 years of accumulated TE knowledge gained through the study of the Arabidopsis genome and covers the known TE families, their relative abundance, and their genomic distribution. It presents our knowledge of the different TE family activities, mobility, population and long-term evolutionary dynamics. Finally, the role of TE as substrates for new genes and their impact on gene expression is illustrated through a few selected demonstrative cases. Promising future directions for TE studies in this species conclude the review.
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13
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Dawe RK. Charting the path to fully synthetic plant chromosomes. Exp Cell Res 2020; 390:111951. [PMID: 32151492 DOI: 10.1016/j.yexcr.2020.111951] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 03/03/2020] [Accepted: 03/05/2020] [Indexed: 02/06/2023]
Abstract
The concepts of synthetic biology have the potential to transform plant genetics, both in how we analyze genetic pathways and how we transfer that knowledge into useful applications. While synthetic biology can be applied at the level of the single gene or small groups of genes, this commentary focuses on the ultimate challenge of designing fully synthetic plant chromosomes. Engineering at this scale will allow us to manipulate whole genome architecture and to modify multiple pathways and traits simultaneously. Advances in genome synthesis make it likely that the initial phases of plant chromosome construction will occur in bacteria and yeast. Here I discuss the next steps, including specific ways of overcoming technical barriers associated with plant transformation, functional centromere design, and ensuring accurate meiotic transmission.
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Affiliation(s)
- R Kelly Dawe
- Department of Genetics and Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA.
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14
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Shortt JA, Ruggiero RP, Cox C, Wacholder AC, Pollock DD. Finding and extending ancient simple sequence repeat-derived regions in the human genome. Mob DNA 2020; 11:11. [PMID: 32095164 PMCID: PMC7027126 DOI: 10.1186/s13100-020-00206-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 02/04/2020] [Indexed: 12/19/2022] Open
Abstract
Background Previously, 3% of the human genome has been annotated as simple sequence repeats (SSRs), similar to the proportion annotated as protein coding. The origin of much of the genome is not well annotated, however, and some of the unidentified regions are likely to be ancient SSR-derived regions not identified by current methods. The identification of these regions is complicated because SSRs appear to evolve through complex cycles of expansion and contraction, often interrupted by mutations that alter both the repeated motif and mutation rate. We applied an empirical, kmer-based, approach to identify genome regions that are likely derived from SSRs. Results The sequences flanking annotated SSRs are enriched for similar sequences and for SSRs with similar motifs, suggesting that the evolutionary remains of SSR activity abound in regions near obvious SSRs. Using our previously described P-clouds approach, we identified ‘SSR-clouds’, groups of similar kmers (or ‘oligos’) that are enriched near a training set of unbroken SSR loci, and then used the SSR-clouds to detect likely SSR-derived regions throughout the genome. Conclusions Our analysis indicates that the amount of likely SSR-derived sequence in the human genome is 6.77%, over twice as much as previous estimates, including millions of newly identified ancient SSR-derived loci. SSR-clouds identified poly-A sequences adjacent to transposable element termini in over 74% of the oldest class of Alu (roughly, AluJ), validating the sensitivity of the approach. Poly-A’s annotated by SSR-clouds also had a length distribution that was more consistent with their poly-A origins, with mean about 35 bp even in older Alus. This work demonstrates that the high sensitivity provided by SSR-Clouds improves the detection of SSR-derived regions and will enable deeper analysis of how decaying repeats contribute to genome structure.
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Affiliation(s)
- Jonathan A Shortt
- 1Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045 USA
| | - Robert P Ruggiero
- 2Department of Biology, Southeast Missouri State University, Cape Girardeau, MO 63701 USA
| | - Corey Cox
- 1Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045 USA
| | - Aaron C Wacholder
- 3Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213 USA
| | - David D Pollock
- 4Department of Biochemistry & Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045 USA
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15
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Ebrahimzadegan R, Houben A, Mirzaghaderi G. Repetitive DNA landscape in essential A and supernumerary B chromosomes of Festuca pratensis Huds. Sci Rep 2019; 9:19989. [PMID: 31882680 PMCID: PMC6934454 DOI: 10.1038/s41598-019-56383-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 12/11/2019] [Indexed: 11/09/2022] Open
Abstract
Here, we characterized the basic properties of repetitive sequences in essential A and supernumerary B chromosomes of Festuca pratensis Huds. This was performed by comparative analysis of low-pass Illumina sequence reads of B chromosome lacking (-B) and B chromosome containing (+B) individuals of F. pratensis. 61% of the nuclear genome is composed of repetitive sequences. 43.1% of the genome are transposons of which DNA transposons and retrotransposons made up 2.3% and 40.8%, respectively. LTR retrotransposons are the most abundant mobile elements and contribute to 40.7% of the genome and divided into Ty3-gypsy and Ty1-copia super families with 32.97% and 7.78% of the genome, respectively. Eighteen different satellite repeats were identified making up 3.9% of the genome. Five satellite repeats were used as cytological markers for chromosome identification and genome analysis in the genus Festuca. Four satellite repeats were identified on B chromosomes among which Fp-Sat48 and Fp-Sat253 were specific to the B chromosome of F. pratensis.
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Affiliation(s)
- Rahman Ebrahimzadegan
- Department of Agronomy and Plant Breeding, Faculty of Agriculture, University of Kurdistan, 6617715175, Sanandaj, Iran
| | - Andreas Houben
- Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung (IPK) Gatersleben, Corrensstrasse 3, 06466, Stadt Seeland, Germany
| | - Ghader Mirzaghaderi
- Department of Agronomy and Plant Breeding, Faculty of Agriculture, University of Kurdistan, 6617715175, Sanandaj, Iran.
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16
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Heterogeneous transposable elements as silencers, enhancers and targets of meiotic recombination. Chromosoma 2019; 128:279-296. [PMID: 31332531 DOI: 10.1007/s00412-019-00718-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 06/25/2019] [Accepted: 07/01/2019] [Indexed: 02/01/2023]
Abstract
During meiosis, DNA double-strand breaks are initiated by the topoisomerase-like enzyme SPO11 and are repaired by inter-sister chromatid and inter-homologue DNA repair pathways. Genome-wide maps of initiating DNA double-strand breaks and inter-homologue repair events are now available for a number of mammalian, fungal and plant species. In mammals, PRDM9 specifies the location of meiotic recombination initiation via recognition of specific DNA sequence motifs by its C2H2 zinc finger array. In fungi and plants, meiotic recombination appears to be initiated less discriminately in accessible chromatin, including at gene promoters. Generally, meiotic crossover is suppressed in highly repetitive genomic regions that are made up of transposable elements (TEs), to prevent deleterious non-allelic homologous recombination events. However, recent and older studies have revealed intriguing relationships between meiotic recombination initiation and repair, and transposable elements. For instance, gene conversion events have been detected in maize centromeric retroelements, mouse MULE-MuDR DNA transposons undergo substantial meiotic recombination initiation, Arabidopsis Helitron TEs are among the hottest of recombination initiation hotspots, and human TE sequences can modify the crossover rate at adjacent PRDM9 motifs in cis. Here, we summarize the relationship between meiotic recombination and TEs, discuss recent insights from highly divergent eukaryotes and highlight outstanding questions in the field.
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17
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Legrand S, Caron T, Maumus F, Schvartzman S, Quadrana L, Durand E, Gallina S, Pauwels M, Mazoyer C, Huyghe L, Colot V, Hanikenne M, Castric V. Differential retention of transposable element-derived sequences in outcrossing Arabidopsis genomes. Mob DNA 2019; 10:30. [PMID: 31346350 PMCID: PMC6636163 DOI: 10.1186/s13100-019-0171-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 06/28/2019] [Indexed: 12/20/2022] Open
Abstract
Background Transposable elements (TEs) are genomic parasites with major impacts on host genome architecture and host adaptation. A proper evaluation of their evolutionary significance has been hampered by the paucity of short scale phylogenetic comparisons between closely related species. Here, we characterized the dynamics of TE accumulation at the micro-evolutionary scale by comparing two closely related plant species, Arabidopsis lyrata and A. halleri. Results Joint genome annotation in these two outcrossing species confirmed that both contain two distinct populations of TEs with either 'recent' or 'old' insertion histories. Identification of rare segregating insertions suggests that diverse TE families contribute to the ongoing dynamics of TE accumulation in the two species. Orthologous TE fragments (i.e. those that have been maintained in both species), tend to be located closer to genes than those that are retained in one species only. Compared to non-orthologous TE insertions, those that are orthologous tend to produce fewer short interfering RNAs, are less heavily methylated when found within or adjacent to genes and these tend to have lower expression levels. These findings suggest that long-term retention of TE insertions reflects their frequent acquisition of adaptive roles and/or the deleterious effects of removing nearly neutral TE insertions when they are close to genes. Conclusion Our results indicate a rapid evolutionary dynamics of the TE landscape in these two outcrossing species, with an important input of a diverse set of new insertions with variable propensity to resist deletion.
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Affiliation(s)
- Sylvain Legrand
- 1Univ. Lille, CNRS, UMR 8198 - Evo-Eco-Paleo, F-59000 Lille, France
| | - Thibault Caron
- 1Univ. Lille, CNRS, UMR 8198 - Evo-Eco-Paleo, F-59000 Lille, France
| | - Florian Maumus
- 2URGI, INRA, Université Paris-Saclay, 78026 Versailles, France
| | - Sol Schvartzman
- 3InBioS - PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000 Liège, Belgium
| | - Leandro Quadrana
- 4IBENS, Département de Biologie, Ecole Normale Supérieure, CNRS, Inserm, PSL Research University, F-75005 Paris, France
| | - Eléonore Durand
- 1Univ. Lille, CNRS, UMR 8198 - Evo-Eco-Paleo, F-59000 Lille, France
| | - Sophie Gallina
- 1Univ. Lille, CNRS, UMR 8198 - Evo-Eco-Paleo, F-59000 Lille, France
| | - Maxime Pauwels
- 1Univ. Lille, CNRS, UMR 8198 - Evo-Eco-Paleo, F-59000 Lille, France
| | - Clément Mazoyer
- 1Univ. Lille, CNRS, UMR 8198 - Evo-Eco-Paleo, F-59000 Lille, France
| | - Lucie Huyghe
- 1Univ. Lille, CNRS, UMR 8198 - Evo-Eco-Paleo, F-59000 Lille, France
| | - Vincent Colot
- 4IBENS, Département de Biologie, Ecole Normale Supérieure, CNRS, Inserm, PSL Research University, F-75005 Paris, France
| | - Marc Hanikenne
- 3InBioS - PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000 Liège, Belgium
| | - Vincent Castric
- 1Univ. Lille, CNRS, UMR 8198 - Evo-Eco-Paleo, F-59000 Lille, France
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Li Q, Li H, Huang W, Xu Y, Zhou Q, Wang S, Ruan J, Huang S, Zhang Z. A chromosome-scale genome assembly of cucumber (Cucumis sativus L.). Gigascience 2019; 8:giz072. [PMID: 31216035 PMCID: PMC6582320 DOI: 10.1093/gigascience/giz072] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 03/13/2019] [Accepted: 05/23/2019] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Accurate and complete reference genome assemblies are fundamental for biological research. Cucumber is an important vegetable crop and model system for sex determination and vascular biology. Low-coverage Sanger sequences and high-coverage short Illumina sequences have been used to assemble draft cucumber genomes, but the incompleteness and low quality of these genomes limit their use in comparative genomics and genetic research. A high-quality and complete cucumber genome assembly is therefore essential. FINDINGS We assembled single-molecule real-time (SMRT) long reads to generate an improved cucumber reference genome. This version contains 174 contigs with a total length of 226.2 Mb and an N50 of 8.9 Mb, and provides 29.0 Mb more sequence data than previous versions. Using 10X Genomics and high-throughput chromosome conformation capture (Hi-C) data, 89 contigs (∼211.0 Mb) were directly linked into 7 pseudo-chromosome sequences. The newly assembled regions show much higher guanine-cytosine or adenine-thymine content than found previously, which is likely to have been inaccessible to Illumina sequencing. The new assembly contains 1,374 full-length long terminal retrotransposons and 1,078 novel genes including 239 tandemly duplicated genes. For example, we found 4 tandemly duplicated tyrosylprotein sulfotransferases, in contrast to the single copy of the gene found previously and in most other plants. CONCLUSION This high-quality genome presents novel features of the cucumber genome and will serve as a valuable resource for genetic research in cucumber and plant comparative genomics.
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Affiliation(s)
- Qing Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, No.12, Haidian District, Beijing 100081, China
| | - Hongbo Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, No.12, Haidian District, Beijing 100081, China
| | - Wu Huang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, No.12, Haidian District, Beijing 100081, China
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, No. 7, Pengfei Road, Dapeng District, Shenzhen 518124, China
| | - Yuanchao Xu
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, No.12, Haidian District, Beijing 100081, China
| | - Qian Zhou
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, No.12, Haidian District, Beijing 100081, China
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, No. 7, Pengfei Road, Dapeng District, Shenzhen 518124, China
| | - Shenhao Wang
- College of Horticulture, Northwest A&F University, Yangling, Shanxi 712100, China
| | - Jue Ruan
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, No. 7, Pengfei Road, Dapeng District, Shenzhen 518124, China
| | - Sanwen Huang
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, No. 7, Pengfei Road, Dapeng District, Shenzhen 518124, China
| | - Zhonghua Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, No.12, Haidian District, Beijing 100081, China
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19
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Liu Q, Li X, Zhou X, Li M, Zhang F, Schwarzacher T, Heslop-Harrison JS. The repetitive DNA landscape in Avena (Poaceae): chromosome and genome evolution defined by major repeat classes in whole-genome sequence reads. BMC PLANT BIOLOGY 2019; 19:226. [PMID: 31146681 PMCID: PMC6543597 DOI: 10.1186/s12870-019-1769-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 04/09/2019] [Indexed: 05/18/2023]
Abstract
BACKGROUND Repetitive DNA motifs - not coding genetic information and repeated millions to hundreds of times - make up the majority of many genomes. Here, we identify the nature, abundance and organization of all the repetitive DNA families in oats (Avena sativa, 2n = 6x = 42, AACCDD), a recognized health-food, and its wild relatives. RESULTS Whole-genome sequencing followed by k-mer and RepeatExplorer graph-based clustering analyses enabled assessment of repetitive DNA composition in common oat and its wild relatives' genomes. Fluorescence in situ hybridization (FISH)-based karyotypes are developed to understand chromosome and repetitive sequence evolution of common oat. We show that some 200 repeated DNA motifs make up 70% of the Avena genome, with less than 20 families making up 20% of the total. Retroelements represent the major component, with Ty3/Gypsy elements representing more than 40% of all the DNA, nearly three times more abundant than Ty1/Copia elements. DNA transposons are about 5% of the total, while tandemly repeated, satellite DNA sequences fit into 55 families and represent about 2% of the genome. The Avena species are monophyletic, but both bioinformatic comparisons of repeats in the different genomes, and in situ hybridization to metaphase chromosomes from the hexaploid species, shows that some repeat families are specific to individual genomes, or the A and D genomes together. Notably, there are terminal regions of many chromosomes showing different repeat families from the rest of the chromosome, suggesting presence of translocations between the genomes. CONCLUSIONS The relatively small number of repeat families shows there are evolutionary constraints on their nature and amplification, with mechanisms leading to homogenization, while repeat characterization is useful in providing genome markers and to assist with future assemblies of this large genome (c. 4100 Mb in the diploid). The frequency of inter-genomic translocations suggests optimum strategies to exploit genetic variation from diploid oats for improvement of the hexaploid may differ from those used widely in bread wheat.
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Affiliation(s)
- Qing Liu
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization / Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.
| | - Xiaoyu Li
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization / Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiangying Zhou
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization / Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Mingzhi Li
- Genepioneer Biotechnologies Co. Ltd., Nanjing, China
| | - Fengjiao Zhang
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing, China
| | - Trude Schwarzacher
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization / Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- Department of Genetics and Genome Biology, University of Leicester, Leicester, LE1 7RH, UK
| | - John Seymour Heslop-Harrison
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization / Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.
- Department of Genetics and Genome Biology, University of Leicester, Leicester, LE1 7RH, UK.
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Madrigal Y, Alzate JF, González F, Pabón-Mora N. Evolution of RADIALIS and DIVARICATA gene lineages in flowering plants with an expanded sampling in non-core eudicots. AMERICAN JOURNAL OF BOTANY 2019; 106:334-351. [PMID: 30845367 DOI: 10.1002/ajb2.1243] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 12/07/2018] [Indexed: 05/18/2023]
Abstract
PREMISE OF THE STUDY Bilateral symmetry in core eudicot flowers is established by the differential expression of CYCLOIDEA (CYC), DICHOTOMA (DICH), and RADIALIS (RAD), which are restricted to the dorsal portion of the flower, and DIVARICATA (DIV), restricted to the ventral and lateral petals. Little is known regarding the evolution of these gene lineages in non-core eudicots, and there are no reports on gene expression that can be used to assess whether the network predates the diversification of core eudicots. METHODS Homologs of the RAD and DIV lineages were isolated from available genomes and transcriptomes, including those of three selected non-core eudicot species, the magnoliid Aristolochia fimbriata and the monocots Cattleya trianae and Hypoxis decumbens. Phylogenetic analyses for each gene lineage were performed. RT-PCR was used to evaluate the expression and putative contribution to floral symmetry in dissected floral organs of the selected species. KEY RESULTS RAD-like genes have undergone at least two duplication events before eudicot diversification, three before monocots and at least four in Orchidaceae. DIV-like genes also duplicated twice before eudicot diversification and underwent independent duplications specific to Orchidaceae. RAD-like and DIV-like genes have differential dorsiventral expression only in C. trianae, which contrasts with the homogeneous expression in the perianth of A. fimbriata. CONCLUSIONS Our results point to a common genetic regulatory network for floral symmetry in monocots and core eudicots, while alternative genetic mechanisms are likely driving the bilateral perianth symmetry in the early-diverging angiosperm Aristolochia.
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Affiliation(s)
- Yesenia Madrigal
- Instituto de Biología, Universidad de Antioquia, AA 1226, Cl. 67 No. 53-108, Medellín, Colombia
| | - Juan Fernando Alzate
- Centro Nacional de Secuenciación Genómica, SIU, Facultad de Medicina, Universidad de Antioquia, Cl. 70 No. 52-21, Medellín, Colombia
| | - Favio González
- Universidad Nacional de Colombia, Facultad de Ciencias, Instituto de Ciencias Naturales, AA. 7495, Bogotá, Colombia
| | - Natalia Pabón-Mora
- Instituto de Biología, Universidad de Antioquia, AA 1226, Cl. 67 No. 53-108, Medellín, Colombia
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21
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Pischedda E, Scolari F, Valerio F, Carballar-Lejarazú R, Catapano PL, Waterhouse RM, Bonizzoni M. Insights Into an Unexplored Component of the Mosquito Repeatome: Distribution and Variability of Viral Sequences Integrated Into the Genome of the Arboviral Vector Aedes albopictus. Front Genet 2019; 10:93. [PMID: 30809249 PMCID: PMC6379468 DOI: 10.3389/fgene.2019.00093] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 01/29/2019] [Indexed: 01/01/2023] Open
Abstract
The Asian tiger mosquito Aedes albopictus is an invasive mosquito and a competent vector for public-health relevant arboviruses such as Chikungunya (Alphavirus), Dengue and Zika (Flavivirus) viruses. Unexpectedly, the sequencing of the genome of this mosquito revealed an unusually high number of integrated sequences with similarities to non-retroviral RNA viruses of the Flavivirus and Rhabdovirus genera. These Non-retroviral Integrated RNA Virus Sequences (NIRVS) are enriched in piRNA clusters and coding sequences and have been proposed to constitute novel mosquito immune factors. However, given the abundance of NIRVS and their variable viral origin, their relative biological roles remain unexplored. Here we used an analytical approach that intersects computational, evolutionary and molecular methods to study the genomic landscape of mosquito NIRVS. We demonstrate that NIRVS are differentially distributed across mosquito genomes, with a core set of seemingly the oldest integrations with similarity to Rhabdoviruses. Additionally, we compare the polymorphisms of NIRVS with respect to that of fast and slow-evolving genes within the Ae. albopictus genome. Overall, NIRVS appear to be less polymorphic than slow-evolving genes, with differences depending on whether they occur in intergenic regions or in piRNA clusters. Finally, two NIRVS that map within the coding sequences of genes annotated as Rhabdovirus RNA-dependent RNA polymerase and the nucleocapsid-encoding gene, respectively, are highly polymorphic and are expressed, suggesting exaptation possibly to enhance the mosquito's antiviral responses. These results greatly advance our understanding of the complexity of the mosquito repeatome and the biology of viral integrations in mosquito genomes.
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Affiliation(s)
- Elisa Pischedda
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Francesca Scolari
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Federica Valerio
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Rebeca Carballar-Lejarazú
- Department of Microbiology & Molecular Genetics, University of California, Irvine, Irvine, CA, United States
| | | | - Robert M. Waterhouse
- Department of Ecology and Evolution, University of Lausanne and Swiss Institute of Bioinformatics, Lausanne, Switzerland
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Dubin MJ, Mittelsten Scheid O, Becker C. Transposons: a blessing curse. CURRENT OPINION IN PLANT BIOLOGY 2018; 42:23-29. [PMID: 29453028 DOI: 10.1016/j.pbi.2018.01.003] [Citation(s) in RCA: 107] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 01/11/2018] [Accepted: 01/16/2018] [Indexed: 05/18/2023]
Abstract
The genomes of most plant species are dominated by transposable elements (TEs). Once considered as 'junk DNA', TEs are now known to have a major role in driving genome evolution. Over the last decade, it has become apparent that some stress conditions and other environmental stimuli can drive bursts of activity of certain TE families and consequently new TE insertions. These can give rise to altered gene expression patterns and phenotypes, with new TE insertions sometimes causing flanking genes to become transcriptionally responsive to the same stress conditions that activated the TE in the first place. Such connections between TE-mediated increases in diversity and an accelerated rate of genome evolution provide powerful mechanisms for plants to adapt more rapidly to new environmental conditions. This review will focus on environmentally induced transposition, the mechanisms by which it alters gene expression, and the consequences for plant genome evolution and breeding.
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Affiliation(s)
- Manu J Dubin
- Université de Lille CNRS, UMR 8198-Evo-Eco-Paleo, Lille, France.
| | - Ortrun Mittelsten Scheid
- Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Vienna Biocenter (VBC), 1030 Vienna, Austria
| | - Claude Becker
- Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Vienna Biocenter (VBC), 1030 Vienna, Austria.
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Choudhury RR, Neuhaus JM, Parisod C. Resolving fine-grained dynamics of retrotransposons: comparative analysis of inferential methods and genomic resources. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 90:979-993. [PMID: 28244250 DOI: 10.1111/tpj.13524] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 02/15/2017] [Accepted: 02/22/2017] [Indexed: 06/06/2023]
Abstract
Transposable elements support genome diversification, but comparison of their proliferation and genomic distribution within and among species is necessary to characterize their role in evolution. Such inferences are challenging because of potential bias with incomplete sampling of repetitive genome regions. Here, using the assembled genome as well as genome skimming datasets in Arabis alpina, we assessed the limits of current approaches inferring the biology of transposable elements. Long terminal repeat retrotransposons (LTR-RTs) identified in the assembled genome were classified into monophyletic lineages (here called tribes), including families of similar copies in Arabis along with elements from related Brassicaceae. Inference of their dynamics using divergence of LTRs in full-length copies and mismatch distribution of genetic variation among all copies congruently highlighted recent transposition bursts, although ancient proliferation events were apparent only with mismatch distribution. Similar inferences of LTR-RT dynamics based on random sequences from genome skimming were highly correlated with assembly-based estimates, supporting accurate analyses from shallow sequencing. Proportions of LTR-RT copies next to genes from both assembled genomes and genome skimming were congruent, pointing to tribes being over- or under-represented in the vicinity of genes. Finally, genome skimming at low coverage revealed accurate inferences of LTR-RT dynamics and distribution, although only the most abundant families appeared robustly analysed at 0.1X. Examining the pitfalls and benefits of approaches relying on different genomic resources, we highlight that random sequencing reads represent adequate data suitably complementing biased samples of LTR-RT copies retrieved from assembled genomes towards comprehensive surveys of the biology of transposable elements.
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Affiliation(s)
| | - Jean-Marc Neuhaus
- Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
| | - Christian Parisod
- Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
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