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Arvas YE, Marakli S, Kaya Y, Kalendar R. The power of retrotransposons in high-throughput genotyping and sequencing. FRONTIERS IN PLANT SCIENCE 2023; 14:1174339. [PMID: 37180380 PMCID: PMC10167742 DOI: 10.3389/fpls.2023.1174339] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Accepted: 04/11/2023] [Indexed: 05/16/2023]
Abstract
The use of molecular markers has become an essential part of molecular genetics through their application in numerous fields, which includes identification of genes associated with targeted traits, operation of backcrossing programs, modern plant breeding, genetic characterization, and marker-assisted selection. Transposable elements are a core component of all eukaryotic genomes, making them suitable as molecular markers. Most of the large plant genomes consist primarily of transposable elements; variations in their abundance contribute to most of the variation in genome size. Retrotransposons are widely present throughout plant genomes, and replicative transposition enables them to insert into the genome without removing the original elements. Various applications of molecular markers have been developed that exploit the fact that these genetic elements are present everywhere and their ability to stably integrate into dispersed chromosomal localities that are polymorphic within a species. The ongoing development of molecular marker technologies is directly related to the deployment of high-throughput genotype sequencing platforms, and this research is of considerable significance. In this review, the practical application to molecular markers, which is a use of technology of interspersed repeats in the plant genome were examined using genomic sources from the past to the present. Prospects and possibilities are also presented.
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Affiliation(s)
- Yunus Emre Arvas
- Department of Biology, Faculty of Sciences, Karadeniz Technical University, Trabzon, Türkiye
| | - Sevgi Marakli
- Department of Molecular Biology and Genetics, Faculty of Arts and Sciences, Yildiz Technical University, Istanbul, Türkiye
| | - Yılmaz Kaya
- Agricultural Biotechnology Department, Faculty of Agriculture, Ondokuz Mayıs University, Samsun, Türkiye
- Department of Biology, Faculty of Science, Kyrgyz-Turkish Manas University, Bishkek, Kyrgyzstan
| | - Ruslan Kalendar
- Center for Life Sciences, National Laboratory Astana, Nazarbayev University, Astana, Kazakhstan
- Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, Helsinki, Finland
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Terletskaya NV, Turzhanova AS, Khapilina ON, Zhumagul MZ, Meduntseva ND, Kudrina NO, Korbozova NK, Kubentayev SA, Kalendar R. Genetic Diversity in Natural Populations of Rhodiola Species of Different Adaptation Strategies. Genes (Basel) 2023; 14:genes14040794. [PMID: 37107552 PMCID: PMC10137911 DOI: 10.3390/genes14040794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/24/2023] [Accepted: 03/24/2023] [Indexed: 03/29/2023] Open
Abstract
Representatives of the Crassulaceae family’s genus Rhodiola are succulents, making them distinctive in a changing environment. One of the most significant tools for analyzing plant resources, including numerous genetic processes in wild populations, is the analysis of molecular genetic polymorphism. This work aimed to look at the polymorphisms of allelic variations of the superoxide dismutase (SOD) and auxin response factor (ARF) gene families, as well as the genetic diversity of five Rhodiola species, using the retrotransposons-based fingerprinting approach. The multi-locus exon-primed intron-crossing (EPIC-PCR) profiling approach was used to examine allelic variations in the SOD and ARF gene families. We implemented the inter-primer binding site (iPBS) PCR amplification technique for genome profiling, which demonstrated a significant level of polymorphism in the Rhodiola samples studied. Natural populations of Rhodiola species have a great capacity for adaptation to unfavorable environmental influences. The genetic variety of wild populations of Rhodiola species leads to their improved tolerance of opposing environmental circumstances and species evolutionary divergence based on the diversity of reproductive systems.
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Affiliation(s)
- Nina V. Terletskaya
- Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Al-Farabi Avenue 71, Almaty 050040, Kazakhstan;
- Institute of Genetic and Physiology, Al-Farabi Avenue 93, Almaty 050040, Kazakhstan; (N.D.M.); (N.O.K.); (N.K.K.)
| | - Ainur S. Turzhanova
- National Center for Biotechnology, Qorghalzhyn Hwy 13, Astana 010000, Kazakhstan; (A.S.T.); (O.N.K.)
| | - Oxana N. Khapilina
- National Center for Biotechnology, Qorghalzhyn Hwy 13, Astana 010000, Kazakhstan; (A.S.T.); (O.N.K.)
| | - Moldir Z. Zhumagul
- Astana International University, Kabanbai Batyr 8, Astana 010000, Kazakhstan;
- Astana Botanical Garden, Orunbur 16, Astana 010000, Kazakhstan;
| | - Nataliya D. Meduntseva
- Institute of Genetic and Physiology, Al-Farabi Avenue 93, Almaty 050040, Kazakhstan; (N.D.M.); (N.O.K.); (N.K.K.)
| | - Nataliya O. Kudrina
- Institute of Genetic and Physiology, Al-Farabi Avenue 93, Almaty 050040, Kazakhstan; (N.D.M.); (N.O.K.); (N.K.K.)
- National Center for Biotechnology, Qorghalzhyn Hwy 13, Astana 010000, Kazakhstan; (A.S.T.); (O.N.K.)
| | - Nazym K. Korbozova
- Institute of Genetic and Physiology, Al-Farabi Avenue 93, Almaty 050040, Kazakhstan; (N.D.M.); (N.O.K.); (N.K.K.)
- National Center for Biotechnology, Qorghalzhyn Hwy 13, Astana 010000, Kazakhstan; (A.S.T.); (O.N.K.)
| | | | - Ruslan Kalendar
- National Laboratory Astana, Nazarbayev University, 53 Kabanbay Batyr Ave., Astana 010000, Kazakhstan
- Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, 00014 Helsinki, Finland
- Correspondence: ; Tel.: +358-294158869
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Ramakrishnan M, Papolu PK, Mullasseri S, Zhou M, Sharma A, Ahmad Z, Satheesh V, Kalendar R, Wei Q. The role of LTR retrotransposons in plant genetic engineering: how to control their transposition in the genome. PLANT CELL REPORTS 2023; 42:3-15. [PMID: 36401648 DOI: 10.1007/s00299-022-02945-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 10/23/2022] [Indexed: 06/16/2023]
Abstract
We briefly discuss that the similarity of LTR retrotransposons to retroviruses is a great opportunity for the development of a genetic engineering tool that exploits intragenic elements in the plant genome for plant genetic improvement. Long terminal repeat (LTR) retrotransposons are very similar to retroviruses but do not have the property of being infectious. While spreading between its host cells, a retrovirus inserts a DNA copy of its genome into the cells. The ability of retroviruses to cause infection with genome integration allows genes to be delivered to cells and tissues. Retrovirus vectors are, however, only specific to animals and insects, and, thus, are not relevant to plant genetic engineering. However, the similarity of LTR retrotransposons to retroviruses is an opportunity to explore the former as a tool for genetic engineering. Although recent long-read sequencing technologies have advanced the knowledge about transposable elements (TEs), the integration of TEs is still unable either to control them or to direct them to specific genomic locations. The use of existing intragenic elements to achieve the desired genome composition is better than using artificial constructs like vectors, but it is not yet clear how to control the process. Moreover, most LTR retrotransposons are inactive and unable to produce complete proteins. They are also highly mutable. In addition, it is impossible to find a full active copy of a LTR retrotransposon out of thousands of its own copies. Theoretically, if these elements were directly controlled and turned on or off using certain epigenetic mechanisms (inducing by stress or infection), LTR retrotransposons could be a great opportunity to develop a genetic engineering tool using intragenic elements in the plant genome. In this review, the recent developments in uncovering the nature of LTR retrotransposons and the possibility of using these intragenic elements as a tool for plant genetic engineering are briefly discussed.
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Affiliation(s)
- Muthusamy Ramakrishnan
- Co-Innovation Center for Sustainable Forestry in Southern China, Bamboo Research Institute, Key Laboratory of National Forestry and Grassland Administration on Subtropical Forest Biodiversity Conservation, College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| | - Pradeep K Papolu
- State Key Laboratory of Subtropical Silviculture, Institute of Bamboo Research, Zhejiang A&F University, Lin'an, Hangzhou, 311300, Zhejiang, China
| | - Sileesh Mullasseri
- Department of Zoology, St. Albert's College (Autonomous), Kochi, 682018, Kerala, India
| | - Mingbing Zhou
- State Key Laboratory of Subtropical Silviculture, Institute of Bamboo Research, Zhejiang A&F University, Lin'an, Hangzhou, 311300, Zhejiang, China
- Zhejiang Provincial Collaborative Innovation Center for Bamboo Resources and High-Efficiency Utilization, Zhejiang A&F University, Lin'an, Hangzhou, 311300, Zhejiang, China
| | - Anket Sharma
- State Key Laboratory of Subtropical Silviculture, Institute of Bamboo Research, Zhejiang A&F University, Lin'an, Hangzhou, 311300, Zhejiang, China
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, USA
| | - Zishan Ahmad
- Co-Innovation Center for Sustainable Forestry in Southern China, Bamboo Research Institute, Key Laboratory of National Forestry and Grassland Administration on Subtropical Forest Biodiversity Conservation, College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| | - Viswanathan Satheesh
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Ruslan Kalendar
- Helsinki Institute of Life Science HiLIFE, University of Helsinki, Biocenter 3, Viikinkaari 1, F1-00014, Helsinki, Finland.
- Institute of Plant Biology and Biotechnology (IPBB), Timiryazev Street 45, 050040, Almaty, Kazakhstan.
| | - Qiang Wei
- Co-Innovation Center for Sustainable Forestry in Southern China, Bamboo Research Institute, Key Laboratory of National Forestry and Grassland Administration on Subtropical Forest Biodiversity Conservation, College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China.
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Papolu PK, Ramakrishnan M, Mullasseri S, Kalendar R, Wei Q, Zou L, Ahmad Z, Vinod KK, Yang P, Zhou M. Retrotransposons: How the continuous evolutionary front shapes plant genomes for response to heat stress. FRONTIERS IN PLANT SCIENCE 2022; 13:1064847. [PMID: 36570931 PMCID: PMC9780303 DOI: 10.3389/fpls.2022.1064847] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Accepted: 11/21/2022] [Indexed: 05/28/2023]
Abstract
Long terminal repeat retrotransposons (LTR retrotransposons) are the most abundant group of mobile genetic elements in eukaryotic genomes and are essential in organizing genomic architecture and phenotypic variations. The diverse families of retrotransposons are related to retroviruses. As retrotransposable elements are dispersed and ubiquitous, their "copy-out and paste-in" life cycle of replicative transposition leads to new genome insertions without the excision of the original element. The overall structure of retrotransposons and the domains responsible for the various phases of their replication is highly conserved in all eukaryotes. The two major superfamilies of LTR retrotransposons, Ty1/Copia and Ty3/Gypsy, are distinguished and dispersed across the chromosomes of higher plants. Members of these superfamilies can increase in copy number and are often activated by various biotic and abiotic stresses due to retrotransposition bursts. LTR retrotransposons are important drivers of species diversity and exhibit great variety in structure, size, and mechanisms of transposition, making them important putative actors in genome evolution. Additionally, LTR retrotransposons influence the gene expression patterns of adjacent genes by modulating potential small interfering RNA (siRNA) and RNA-directed DNA methylation (RdDM) pathways. Furthermore, comparative and evolutionary analysis of the most important crop genome sequences and advanced technologies have elucidated the epigenetics and structural and functional modifications driven by LTR retrotransposon during speciation. However, mechanistic insights into LTR retrotransposons remain obscure in plant development due to a lack of advancement in high throughput technologies. In this review, we focus on the key role of LTR retrotransposons response in plants during heat stress, the role of centromeric LTR retrotransposons, and the role of LTR retrotransposon markers in genome expression and evolution.
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Affiliation(s)
- Pradeep K. Papolu
- State Key Laboratory of Subtropical Silviculture, Bamboo Industry Institute, Zhejiang A&F University, Hangzhou, Zhejiang, China
| | - Muthusamy Ramakrishnan
- State Key Laboratory of Subtropical Silviculture, Bamboo Industry Institute, Zhejiang A&F University, Hangzhou, Zhejiang, China
- Co-Innovation Center for Sustainable Forestry in Southern China, Bamboo Research Institute, Key Laboratory of National Forestry and Grassland Administration on Subtropical Forest Biodiversity Conservation, College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu, China
| | - Sileesh Mullasseri
- Department of Zoology, St. Albert’s College (Autonomous), Kochi, Kerala, India
| | - Ruslan Kalendar
- Helsinki Institute of Life Science HiLIFE, Biocenter 3, University of Helsinki, Helsinki, Finland
- National Laboratory Astana, Nazarbayev University, Astana, Kazakhstan
| | - Qiang Wei
- Co-Innovation Center for Sustainable Forestry in Southern China, Bamboo Research Institute, Key Laboratory of National Forestry and Grassland Administration on Subtropical Forest Biodiversity Conservation, College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu, China
| | - Long−Hai Zou
- State Key Laboratory of Subtropical Silviculture, Bamboo Industry Institute, Zhejiang A&F University, Hangzhou, Zhejiang, China
| | - Zishan Ahmad
- Co-Innovation Center for Sustainable Forestry in Southern China, Bamboo Research Institute, Key Laboratory of National Forestry and Grassland Administration on Subtropical Forest Biodiversity Conservation, College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu, China
| | | | - Ping Yang
- State Key Laboratory of Subtropical Silviculture, Bamboo Industry Institute, Zhejiang A&F University, Hangzhou, Zhejiang, China
- Zhejiang Provincial Collaborative Innovation Center for Bamboo Resources and High-Efficiency Utilization, Zhejiang A&F University, Hangzhou, Zhejiang, China
| | - Mingbing Zhou
- State Key Laboratory of Subtropical Silviculture, Bamboo Industry Institute, Zhejiang A&F University, Hangzhou, Zhejiang, China
- Zhejiang Provincial Collaborative Innovation Center for Bamboo Resources and High-Efficiency Utilization, Zhejiang A&F University, Hangzhou, Zhejiang, China
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Kalendar R. A Guide to Using FASTPCR Software for PCR, In Silico PCR, and Oligonucleotide Analysis. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2021; 2392:223-243. [PMID: 34773626 DOI: 10.1007/978-1-0716-1799-1_16] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The FastPCR software is an integrated tool environment for PCR primer and probe design and for prediction of oligonucleotide properties. The software provides comprehensive tools for designing primers for most PCR and perspective applications, including standard, multiplex, long-distance, inverse, real-time with TaqMan probe, Xtreme Chain Reaction (XCR), group-specific, overlap extension PCR for multifragment assembling cloning, and isothermal amplification (Loop-mediated Isothermal Amplification). A program is available to design specific oligonucleotide sets for long sequence assembly by ligase chain reaction and to design multiplexed of overlapping and nonoverlapping DNA amplicons that tile across a region(s) of interest for targeted next-generation sequencing, competitive allele-specific PCR (KASP)-based genotyping assay for single-nucleotide polymorphisms and insertions and deletions at specific loci, among other features. The in silico PCR primer or probe search includes comprehensive analyses of individual primers and primer pairs. FastPCR includes various bioinformatics tools for analysis and searching of sequences, restriction I-II-III-type enzyme endonuclease analysis, and pattern searching. The program also supports the assembly of a set of contiguous sequences, consensus sequence generation, and sequence similarity and conservancy analysis. FastPCR performs efficient and complete detection of various repeat types with visual display. FastPCR allows for sequence file batch processing that is essential for automation. The software is available for download at https://primerdigital.com/fastpcr.html and online version at https://primerdigital.com/tools/pcr.html .
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Affiliation(s)
- Ruslan Kalendar
- PrimerDigital Ltd, Biocentre 3, Helsinki, Finland. .,National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan.
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Khapilina O, Turzhanova A, Danilova A, Tumenbayeva A, Shevtsov V, Kotukhov Y, Kalendar R. Primer Binding Site (PBS) Profiling of Genetic Diversity of Natural Populations of Endemic Species Allium ledebourianum Schult. BIOTECH 2021; 10:23. [PMID: 35822797 PMCID: PMC9245474 DOI: 10.3390/biotech10040023] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/25/2021] [Accepted: 10/11/2021] [Indexed: 11/20/2022] Open
Abstract
Endemic species are especially vulnerable to biodiversity loss caused by isolation or habitat specificity, small population size, and anthropogenic factors. Endemic species biodiversity analysis has a critically important global value for the development of conservation strategies. The rare onion Allium ledebourianum is a narrow-lined endemic species, with natural populations located in the extreme climatic conditions of the Kazakh Altai. A. ledebourianum populations are decreasing everywhere due to anthropogenic impact, and therefore, this species requires preservation and protection. Conservation of this rare species is associated with monitoring studies to investigate the genetic diversity of natural populations. Fundamental components of eukaryote genome include multiple classes of interspersed repeats. Various PCR-based DNA fingerprinting methods are used to detect chromosomal changes related to recombination processes of these interspersed elements. These methods are based on interspersed repeat sequences and are an effective approach for assessing the biological diversity of plants and their variability. We applied DNA profiling approaches based on conservative sequences of interspersed repeats to assess the genetic diversity of natural A. ledebourianum populations located in the territory of Kazakhstan Altai. The analysis of natural A. ledebourianum populations, carried out using the DNA profiling approach, allowed the effective differentiation of the populations and assessment of their genetic diversity. We used conservative sequences of tRNA primer binding sites (PBS) of the long-terminal repeat (LTR) retrotransposons as PCR primers. Amplification using the three most effective PBS primers generated 628 PCR amplicons, with an average of 209 amplicons. The average polymorphism level varied from 34% to 40% for all studied samples. Resolution analysis of the PBS primers showed all of them to have high or medium polymorphism levels, which varied from 0.763 to 0.965. Results of the molecular analysis of variance showed that the general biodiversity of A. ledebourianum populations is due to interpopulation (67%) and intrapopulation (33%) differences. The revealed genetic diversity was higher in the most distant population of A. ledebourianum LD64, located on the Sarymsakty ridge of Southern Altai. This is the first genetic diversity study of the endemic species A. ledebourianum using DNA profiling approaches. This work allowed us to collect new genetic data on the structure of A. ledebourianum populations in the Altai for subsequent development of preservation strategies to enhance the reproduction of this relict species. The results will be useful for the conservation and exploitation of this species, serving as the basis for further studies of its evolution and ecology.
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Affiliation(s)
- Oxana Khapilina
- National Center for Biotechnology, Korgalzhin Hwy 13/5, Nur-Sultan 010000, Kazakhstan; (A.T.); (A.T.); (V.S.)
| | - Ainur Turzhanova
- National Center for Biotechnology, Korgalzhin Hwy 13/5, Nur-Sultan 010000, Kazakhstan; (A.T.); (A.T.); (V.S.)
| | - Alevtina Danilova
- Altai Botanical Garden, Yermakova Str 1, Ridder 070000, Kazakhstan; (A.D.); (Y.K.)
| | - Asem Tumenbayeva
- National Center for Biotechnology, Korgalzhin Hwy 13/5, Nur-Sultan 010000, Kazakhstan; (A.T.); (A.T.); (V.S.)
| | - Vladislav Shevtsov
- National Center for Biotechnology, Korgalzhin Hwy 13/5, Nur-Sultan 010000, Kazakhstan; (A.T.); (A.T.); (V.S.)
| | - Yuri Kotukhov
- Altai Botanical Garden, Yermakova Str 1, Ridder 070000, Kazakhstan; (A.D.); (Y.K.)
| | - Ruslan Kalendar
- National Laboratory Astana, Nazarbayev University, Nur-Sultan 010000, Kazakhstan
- Helsinki Institute of Life Science HiLIFE, Biocenter 3, Viikinkaari 1, University of Helsinki, FI-00014 Helsinki, Finland
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Orłowska R, Pachota KA, Dynkowska WM, Niedziela A, Bednarek PT. Androgenic-Induced Transposable Elements Dependent Sequence Variation in Barley. Int J Mol Sci 2021; 22:ijms22136783. [PMID: 34202586 PMCID: PMC8268840 DOI: 10.3390/ijms22136783] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/14/2021] [Accepted: 06/22/2021] [Indexed: 01/10/2023] Open
Abstract
A plant genome usually encompasses different families of transposable elements (TEs) that may constitute up to 85% of nuclear DNA. Under stressful conditions, some of them may activate, leading to sequence variation. In vitro plant regeneration may induce either phenotypic or genetic and epigenetic changes. While DNA methylation alternations might be related, i.e., to the Yang cycle problems, DNA pattern changes, especially DNA demethylation, may activate TEs that could result in point mutations in DNA sequence changes. Thus, TEs have the highest input into sequence variation (SV). A set of barley regenerants were derived via in vitro anther culture. High Performance Liquid Chromatography (RP-HPLC), used to study the global DNA methylation of donor plants and their regenerants, showed that the level of DNA methylation increased in regenerants by 1.45% compared to the donors. The Methyl-Sensitive Transposon Display (MSTD) based on methylation-sensitive Amplified Fragment Length Polymorphism (metAFLP) approach demonstrated that, depending on the selected elements belonging to the TEs family analyzed, varying levels of sequence variation were evaluated. DNA sequence contexts may have a different impact on SV generated by distinct mobile elements belonged to various TE families. Based on the presented study, some of the selected mobile elements contribute differently to TE-related SV. The surrounding context of the TEs DNA sequence is possibly important here, and the study explained some part of SV related to those contexts.
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Alvarez JB, Castellano L, Huertas-García AB, Guzmán C. Molecular characterization of five novel Wx-A1 alleles in common wheat including one silent allele by transposon insertion. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 305:110843. [PMID: 33691970 DOI: 10.1016/j.plantsci.2021.110843] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 01/26/2021] [Accepted: 02/02/2021] [Indexed: 05/21/2023]
Abstract
Wheat starch is composed of two glucose polymers, amylose and amylopectin. Although several starch synthases are responsible for its synthesis, only the waxy protein is associated with the amylose synthesis. The waxy protein composition of 45 Spanish common wheat landraces from Andalusia (southern Spain) was evaluated. Within these materials, five novel alleles for the Wx-A1 gene were detected. Four of them showed functional proteins (Wx-A1p, Wx-A1q, Wx-A1r and Wx-A1s), although some amino acid changes were found in the mature protein sequence. However, one of them (Wx-A1t) exhibited loss of the Wx-A1 protein, and its base sequence contained one large insert (1,073 bp) in the tenth exon, that interrupted the ORF of the Wx-A1 gene. This insert exhibited the characteristics of a Class II transposon of the Mutator superfamily, which had not been described previously, and has been named Baetica. The conservation of such inserts could be related to their low effect on vital properties of the plants, as occurs with most of the genes associated with technological quality. In conclusion, the evaluation of old wheat landraces showed that, in addition to their use as alternative crops, these materials could be a useful source of interesting genes in wheat quality improvement.
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Affiliation(s)
- Juan B Alvarez
- Departamento de Genética, Escuela Técnica Superior de Ingeniería Agronómica y de Montes, Edificio Gregor Mendel, Campus de Rabanales, Universidad de Córdoba, CeiA3, ES-14071, Córdoba, Spain.
| | - Laura Castellano
- Departamento de Genética, Escuela Técnica Superior de Ingeniería Agronómica y de Montes, Edificio Gregor Mendel, Campus de Rabanales, Universidad de Córdoba, CeiA3, ES-14071, Córdoba, Spain.
| | - Ana B Huertas-García
- Departamento de Genética, Escuela Técnica Superior de Ingeniería Agronómica y de Montes, Edificio Gregor Mendel, Campus de Rabanales, Universidad de Córdoba, CeiA3, ES-14071, Córdoba, Spain.
| | - Carlos Guzmán
- Departamento de Genética, Escuela Técnica Superior de Ingeniería Agronómica y de Montes, Edificio Gregor Mendel, Campus de Rabanales, Universidad de Córdoba, CeiA3, ES-14071, Córdoba, Spain.
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9
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Retrotransposable Elements: DNA Fingerprinting and the Assessment of Genetic Diversity. Methods Mol Biol 2021; 2222:263-286. [PMID: 33301099 DOI: 10.1007/978-1-0716-0997-2_15] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Retrotransposable elements (RTEs) are highly common mobile genetic elements that are composed of several classes and make up the majority of eukaryotic genomes. The "copy-out and paste-in" life cycle of replicative transposition in these dispersive and ubiquitous RTEs leads to new genome insertions without excision of the original element. RTEs are important drivers of species diversity; they exhibit great variety in structure, size, and mechanisms of transposition, making them important putative components in genome evolution. Accordingly, various applications have been developed to explore the polymorphisms in RTE insertion patterns. These applications include conventional or anchored polymerase chain reaction (PCR) and quantitative or digital PCR with primers designed for the 5' or 3' junction. Marker systems exploiting these PCR methods can be easily developed and are inexpensively used in the absence of extensive genome sequence data. The main inter-repeat amplification polymorphism techniques include inter-retrotransposon amplified polymorphism (IRAP), retrotransposon microsatellite amplified polymorphism (REMAP), and Inter-Primer Binding Site (iPBS) for PCR amplification with a single or two primers.
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Higgins P, Grace CA, Lee SA, Goddard MR. Whole-genome sequencing from the New Zealand Saccharomyces cerevisiae population reveals the genomic impacts of novel microbial range expansion. G3-GENES GENOMES GENETICS 2021; 11:6044130. [PMID: 33561237 PMCID: PMC7849907 DOI: 10.1093/g3journal/jkaa027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 11/23/2020] [Indexed: 11/14/2022]
Abstract
Saccharomyces cerevisiae is extensively utilized for commercial fermentation, and is also an important biological model; however, its ecology has only recently begun to be understood. Through the use of whole-genome sequencing, the species has been characterized into a number of distinct subpopulations, defined by geographical ranges and industrial uses. Here, the whole-genome sequences of 104 New Zealand (NZ) S. cerevisiae strains, including 52 novel genomes, are analyzed alongside 450 published sequences derived from various global locations. The impact of S. cerevisiae novel range expansion into NZ was investigated and these analyses reveal the positioning of NZ strains as a subgroup to the predominantly European/wine clade. A number of genomic differences with the European group correlate with range expansion into NZ, including 18 highly enriched single-nucleotide polymorphism (SNPs) and novel Ty1/2 insertions. While it is not possible to categorically determine if any genetic differences are due to stochastic process or the operations of natural selection, we suggest that the observation of NZ-specific copy number increases of four sugar transporter genes in the HXT family may reasonably represent an adaptation in the NZ S. cerevisiae subpopulation, and this correlates with the observations of copy number changes during adaptation in small-scale experimental evolution studies.
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Affiliation(s)
- Peter Higgins
- The School of Life Sciences, College of Science, University of Lincoln, Brayford Pool, Lincoln, LN6 7TS, UK
| | - Cooper A Grace
- Department of Biology, York Biomedical Research Institute, University of York, Heslington, York, YO10 5DD, UK.,Department of Biological and Geographical Sciences, University of Huddersfield, Queensgate, Huddersfield, HD1 3DH, UK
| | - Soon A Lee
- The School of Biological Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Matthew R Goddard
- The School of Life Sciences, College of Science, University of Lincoln, Brayford Pool, Lincoln, LN6 7TS, UK.,The School of Biological Sciences, University of Auckland, Auckland 1142, New Zealand
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11
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Khapilina O, Raiser O, Danilova A, Shevtsov V, Turzhanova A, Kalendar R. DNA profiling and assessment of genetic diversity of relict species Allium altaicum Pall. on the territory of Altai. PeerJ 2021; 9:e10674. [PMID: 33510974 PMCID: PMC7798630 DOI: 10.7717/peerj.10674] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 12/09/2020] [Indexed: 12/18/2022] Open
Abstract
Analysis of the genetic diversity of natural populations of threatened and endangered species of plants is a main aspect of conservation strategy. The endangered species Allium altaicum is a relict plant of the Ice Age and natural populations are located in extreme climatic conditions of Kazakstan's Altai Mountains. Mobile genetic elements and other interspersed repeats are basic components of a eukaryote genome, which can activate under stress conditions and indirectly promote the survival of an organism against environmental stresses. Detections of chromosomal changes related to recombination processes of mobile genetic elements are performed by various PCR methods. These methods are based on interspersed repeat sequences and are an effective tool for research of biological diversity of plants and their variability. In our research, we used conservative sequences of tRNA primer binding sites (PBS) when initializing the retrotransposon replication as PCR primers to research the genetic diversity of 12 natural populations of A. altaicum found in various ecogeographic conditions of the Kazakhstani Altai. High efficiency of the PBS amplification method used was observed already at the intrapopulation level. Unique amplicons representative of a certain population were found at the intrapopulation level. Analysis of molecular dispersion revealed that the biodiversity of populations of mountainous and lowland A. altaicum is due to intrapopulation differences for climatic zones of habitation. This is likely conditional upon predominance of vegetative reproduction over seed reproduction in some populations. In the case of vegetative reproduction, somatic recombination related to the activity of mobile genetic elements are preserved in subsequent generations. This leads to an increase of intrapopulation genetic diversity. Thus, high genetic diversity was observed in populations such as A. altaicum located in the territory of the Kalbinskii Altai, whereas the minimum diversity was observed in the populations of the Leninororsk ecogeographic group. Distinctions between these populations were also identified depending on the areas of their distribution. Low-land and mid-mountain living environments are characterized by a great variety of shapes and plasticity. This work allowed us to obtain new genetic data on the structure of A. altaicum populations on the territory of the Kazakhstan Altai for the subsequent development of preservation and reproduction strategies for this relict species.
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Affiliation(s)
| | - Olesya Raiser
- National Center for Biotechnology, Nur-Sultan, Kazakhstan
| | | | | | | | - Ruslan Kalendar
- Department of Agricultural Sciences, University of Helsinki, Helsinki, Finland.,National Laboratory Astana, Nazarbayev University, Nur-Sultan, Aqmola, Kazakhstan
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12
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Parisod C, Badaeva ED. Chromosome restructuring among hybridizing wild wheats. THE NEW PHYTOLOGIST 2020; 226:1263-1273. [PMID: 31913521 DOI: 10.1111/nph.16415] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 12/29/2019] [Indexed: 06/10/2023]
Abstract
The wheat group offers an outstanding system to address the interplay between hybridization, chromosomal evolution and biological diversification. Most diploid wild wheats originated following hybridization between the A-genome lineage and the B-genome lineage some 4 Myr ago, resulting in an admixed D-genome lineage that presented dramatic radiation accompanied by considerable changes in genome size and chromosomal rearrangements. Comparative profiling of low-copy genes, repeated sequences and transposable elements among those divergent species characterized by different karyotypes highlights high genome dynamics and sheds new light on the processes underlying chromosomal evolution in wild wheats. One of the hybrid clades presents upsizing of metacentric chromosomes going along with the proliferation of specific repeats (i.e. 'genomic obesity'), whereas other species show stable genome size associated with increasing chromosomal asymmetry. Genetic and ecological variation in those specialized species suggest that genome restructuring was coupled with adaptive processes to support the evolution of a majority of acrocentric chromosomes. This synthesis of current knowledge on genome restructuring across the diversity of wild wheats paves the way towards surveys based on latest sequencing technologies to characterize valuable resources and address the significance of chromosomal evolution in species with complex genomes.
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Affiliation(s)
- Christian Parisod
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, Bern, 3013, Switzerland
| | - Ekaterina D Badaeva
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Gubkin St. 3, Moscow, 119991, Russia
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13
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Shams I, Raskina O. Supernumerary B Chromosomes and Plant Genome Changes: A Snapshot of Wild Populations of Aegilops speltoides Tausch ( Poaceae, Triticeae). Int J Mol Sci 2020; 21:ijms21113768. [PMID: 32466617 PMCID: PMC7312783 DOI: 10.3390/ijms21113768] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 05/20/2020] [Accepted: 05/22/2020] [Indexed: 01/12/2023] Open
Abstract
In various eukaryotes, supernumerary B chromosomes (Bs) are an optional genomic component that affect their integrity and functioning. In the present study, the impact of Bs on the current changes in the genome of goatgrass, Aegilops speltoides, was addressed. Individual plants from contrasting populations with and without Bs were explored using fluorescence in situ hybridization. In parallel, abundances of the Ty1-copia, Ty3-gypsy, and LINE retrotransposons (TEs), and the species-specific Spelt1 tandem repeat (TR) in vegetative and generative spike tissues were estimated by real-time quantitative PCR. The results revealed: (i) ectopic associations between Bs and the regular A chromosomes, and (ii) cell-specific rearrangements of Bs in both mitosis and microgametogenesis. Further, the copy numbers of TEs and TR varied significantly between (iii) genotypes and (iv) different spike tissues in the same plant(s). Finally, (v) in plants with and without Bs from different populations, genomic abundances and/or copy number dynamics of TEs and TR were similar. These findings indicate that fluctuations in TE and TR copy numbers are associated with DNA damage and repair processes during cell proliferation and differentiation, and ectopic recombination is one of the mechanisms by which Bs play a role in genome changes.
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14
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Turzhanova A, Khapilina ON, Tumenbayeva A, Shevtsov V, Raiser O, Kalendar R. Genetic diversity of Alternaria species associated with black point in wheat grains. PeerJ 2020; 8:e9097. [PMID: 32411537 PMCID: PMC7207207 DOI: 10.7717/peerj.9097] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 04/09/2020] [Indexed: 12/12/2022] Open
Abstract
The genus Alternaria is a widely distributed major plant pathogen that can act as a saprophyte in plant debris. Fungi of this genus frequently infect cereal crops and cause such diseases as black point and wheat leaf blight, which decrease the yield and quality of cereal products. A total of 25 Alternaria sp. isolates were collected from germ grains of various wheat cultivars from different geographic regions in Kazakhstan. We investigated the genetic relationships of the main Alternaria species related to black point disease of wheat in Kazakhstan, using the inter-primer binding site (iPBS) DNA profiling technique. We used 25 retrotransposon-based iPBS primers to identify the differences among and within Alternaria species populations, and analyzed the variation using clustering (UPGMA) and statistical approaches (AMOVA). Isolates of Alternaria species clustered into two main genetic groups, with species of A.alternata and A.tennuissima forming one cluster, and isolates of A. infectoria forming another. The genetic diversity found using retrotransposon profiles was strongly correlated with geographic data. Overall, the iPBS fingerprinting technique is highly informative and useful for the evaluation of genetic diversity and relationships of Alternaria species.
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Affiliation(s)
| | | | | | | | - Olesya Raiser
- National Center for Biotechnology, Nur-Sultan, Kazakhstan
| | - Ruslan Kalendar
- Department of Agricultural Sciences, University of Helsinki, Helsinki, Uusimaa, Finland
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15
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Kalendar R, Raskina O, Belyayev A, Schulman AH. Long Tandem Arrays of Cassandra Retroelements and Their Role in Genome Dynamics in Plants. Int J Mol Sci 2020; 21:ijms21082931. [PMID: 32331257 PMCID: PMC7215508 DOI: 10.3390/ijms21082931] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 04/15/2020] [Accepted: 04/17/2020] [Indexed: 02/07/2023] Open
Abstract
Retrotransposable elements are widely distributed and diverse in eukaryotes. Their copy number increases through reverse-transcription-mediated propagation, while they can be lost through recombinational processes, generating genomic rearrangements. We previously identified extensive structurally uniform retrotransposon groups in which no member contains the gag, pol, or env internal domains. Because of the lack of protein-coding capacity, these groups are non-autonomous in replication, even if transcriptionally active. The Cassandra element belongs to the non-autonomous group called terminal-repeat retrotransposons in miniature (TRIM). It carries 5S RNA sequences with conserved RNA polymerase (pol) III promoters and terminators in its long terminal repeats (LTRs). Here, we identified multiple extended tandem arrays of Cassandra retrotransposons within different plant species, including ferns. At least 12 copies of repeated LTRs (as the tandem unit) and internal domain (as a spacer), giving a pattern that resembles the cellular 5S rRNA genes, were identified. A cytogenetic analysis revealed the specific chromosomal pattern of the Cassandra retrotransposon with prominent clustering at and around 5S rDNA loci. The secondary structure of the Cassandra retroelement RNA is predicted to form super-loops, in which the two LTRs are complementary to each other and can initiate local recombination, leading to the tandem arrays of Cassandra elements. The array structures are conserved for Cassandra retroelements of different species. We speculate that recombination events similar to those of 5S rRNA genes may explain the wide variation in Cassandra copy number. Likewise, the organization of 5S rRNA gene sequences is very variable in flowering plants; part of what is taken for 5S gene copy variation may be variation in Cassandra number. The role of the Cassandra 5S sequences remains to be established.
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Affiliation(s)
- Ruslan Kalendar
- Department of Agricultural Sciences, University of Helsinki, P.O. Box 27 (Latokartanonkaari 5), FI-00014 Helsinki, Finland
- RSE “National Center for Biotechnology”, Korgalzhyn Highway 13/5, Nur-Sultan 010000, Kazakhstan
- Correspondence: (R.K.); (A.H.S.)
| | - Olga Raskina
- Institute of Evolution, University of Haifa, Mount Carmel, Haifa 31905, Israel;
| | - Alexander Belyayev
- Laboratory of Molecular Cytogenetics and Karyology, Institute of Botany of the ASCR, Zámek 1, CZ-252 43 Průhonice, Czech Republic;
| | - Alan H. Schulman
- Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland
- Institute of Biotechnology and Viikki Plant Science Centre, University of Helsinki, P.O. Box 65, FI-00014 Helsinki, Finland
- Correspondence: (R.K.); (A.H.S.)
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16
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High-throughput retrotransposon-based genetic diversity of maize germplasm assessment and analysis. Mol Biol Rep 2020; 47:1589-1603. [PMID: 31919750 DOI: 10.1007/s11033-020-05246-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 01/03/2020] [Indexed: 01/08/2023]
Abstract
Maize is one of the world's most important crops and a model for grass genome research. Long terminal repeat (LTR) retrotransposons comprise most of the maize genome; their ability to produce new copies makes them efficient high-throughput genetic markers. Inter-retrotransposon-amplified polymorphisms (IRAPs) were used to study the genetic diversity of maize germplasm. Five LTR retrotransposons (Huck, Tekay, Opie, Ji, and Grande) were chosen, based on their large number of copies in the maize genome, whereas polymerase chain reaction primers were designed based on consensus LTR sequences. The LTR primers showed high quality and reproducible DNA fingerprints, with a total of 677 bands including 392 polymorphic bands showing 58% polymorphism between maize hybrid lines. These markers were used to identify genetic similarities among all lines of maize. Analysis of genetic similarity was carried out based on polymorphic amplicon profiles and genetic similarity phylogeny analysis. This diversity was expected to display ecogeographical patterns of variation and local adaptation. The clustering method showed that the varieties were grouped into three clusters differing in ecogeographical origin. Each of these clusters comprised divergent hybrids with convergent characters. The clusters reflected the differences among maize hybrids and were in accordance with their pedigree. The IRAP technique is an efficient high-throughput genetic marker-generating method.
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17
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Development and Deployment of High-Throughput Retrotransposon-Based Markers Reveal Genetic Diversity and Population Structure of Asian Bamboo. FORESTS 2019. [DOI: 10.3390/f11010031] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Bamboo, a non-timber grass species, known for exceptionally fast growth is a commercially viable crop. Long terminal repeat (LTR) retrotransposons, the main class I mobile genetic elements in plant genomes, are highly abundant (46%) in bamboo, contributing to genome diversity. They play significant roles in the regulation of gene expression, chromosome size and structure as well as in genome integrity. Due to their random insertion behavior, interspaces of retrotransposons can vary significantly among bamboo genotypes. Capitalizing this feature, inter-retrotransposon amplified polymorphism (IRAP) is a high-throughput marker system to study the genetic diversity of plant species. To date, there are no transposon based markers reported from the bamboo genome and particularly using IRAP markers on genetic diversity. Phyllostachys genus of Asian bamboo is the largest of the Bambusoideae subfamily, with great economic importance. We report structure-based analysis of bamboo genome for the LTR-retrotransposon superfamilies, Ty3-gypsy and Ty1-copia, which revealed a total of 98,850 retrotransposons with intact LTR sequences at both the ends. Grouped into 64,281 clusters/scaffold using CD-HIT-EST software, only 13 clusters of retroelements were found with more than 30 LTR sequences and with at least one copy having all intact protein domains such as gag and polyprotein. A total of 16 IRAP primers were synthesized, based on the high copy numbers of conserved LTR sequences. A study using these IRAP markers on genetic diversity and population structure of 58 Asian bamboo accessions belonging to the genus Phyllostachys revealed 3340 amplicons with an average of 98% polymorphism. The bamboo accessions were collected from nine different provinces of China, as well as from Italy and America. A three phased approach using hierarchical clustering, principal components and a model based population structure divided the bamboo accessions into four sub-populations, PhSP1, PhSP2, PhSP3 and PhSP4. All the three analyses produced significant sub-population wise consensus. Further, all the sub-populations revealed admixture of alleles. The analysis of molecular variance (AMOVA) among the sub-populations revealed high intra-population genetic variation (75%) than inter-population. The results suggest that Phyllostachys bamboos are not well evolutionarily diversified, although geographic speciation could have occurred at a limited level. This study highlights the usability of IRAP markers in determining the inter-species variability of Asian bamboos.
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18
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Dhar MK, Kour J, Kaul S. Origin, Behaviour, and Transmission of B Chromosome with Special Reference to Plantago lagopus. Genes (Basel) 2019; 10:E152. [PMID: 30781667 PMCID: PMC6410184 DOI: 10.3390/genes10020152] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 12/11/2018] [Accepted: 12/12/2018] [Indexed: 11/30/2022] Open
Abstract
B chromosomes have been reported in many eukaryotic organisms. These chromosomes occur in addition to the standard complement of a species. Bs do not pair with any of the A chromosomes and they have generally been considered to be non-essential and genetically inert. However, due to tremendous advancements in the technologies, the molecular composition of B chromosomes has been determined. The sequencing data has revealed that B chromosomes have originated from A chromosomes and they are rich in repetitive elements. In our laboratory, a novel B chromosome was discovered in Plantago lagopus. Using molecular cytogenetic techniques, the B chromosome was found to be composed of ribosomal DNA sequences. However, further characterization of the chromosome using next generation sequencing (NGS) etc. revealed that the B chromosome is a mosaic of sequences derived from A chromosomes, 5S ribosomal DNA (rDNA), 45S rDNA, and various types of repetitive elements. The transmission of B chromosome through the female sex track did not follow the Mendelian principles. The chromosome was found to have drive due to which it was perpetuating in populations. The present paper attempts to summarize the information on nature, transmission, and origin of B chromosomes, particularly the current status of our knowledge in P. lagopus.
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Affiliation(s)
- Manoj K Dhar
- Genome Research Laboratory, School of Biotechnology, University of Jammu, Jammu-180006, India.
| | - Jasmeet Kour
- Genome Research Laboratory, School of Biotechnology, University of Jammu, Jammu-180006, India.
| | - Sanjana Kaul
- Genome Research Laboratory, School of Biotechnology, University of Jammu, Jammu-180006, India.
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19
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Marques A, Klemme S, Houben A. Evolution of Plant B Chromosome Enriched Sequences. Genes (Basel) 2018; 9:genes9100515. [PMID: 30360448 PMCID: PMC6210368 DOI: 10.3390/genes9100515] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 10/13/2018] [Accepted: 10/18/2018] [Indexed: 01/10/2023] Open
Abstract
B chromosomes are supernumerary chromosomes found in addition to the normal standard chromosomes (A chromosomes). B chromosomes are well known to accumulate several distinct types of repeated DNA elements. Although the evolution of B chromosomes has been the subject of numerous studies, the mechanisms of accumulation and evolution of repetitive sequences are not fully understood. Recently, new genomic approaches have shed light on the origin and accumulation of different classes of repetitive sequences in the process of B chromosome formation and evolution. Here we discuss the impact of repetitive sequences accumulation on the evolution of plant B chromosomes.
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Affiliation(s)
- André Marques
- Laboratory of Genetic Resources, Federal University of Alagoas, Av. Manoel Severino Barbosa, 57309-005 Arapiraca-AL, Brazil.
| | - Sonja Klemme
- Biology Centre, Czech Academy of Sciences, Institute of Plant Molecular Biology, Branišovská 31, CZ-37005 České Budějovice, Czech Republic.
| | - Andreas Houben
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, 06466 Gatersleben, Germany.
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20
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Transposable Elements in the Organization and Diversification of the Genome of Aegilops speltoides Tausch (Poaceae, Triticeae). Int J Genomics 2018; 2018:4373089. [PMID: 30356408 PMCID: PMC6178165 DOI: 10.1155/2018/4373089] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 08/19/2018] [Indexed: 12/31/2022] Open
Abstract
Repetitive DNA-specifically, transposable elements (TEs)-is a prevailing genomic fraction in cereals that underlies extensive genome reshuffling and intraspecific diversification in the wild. Although large amounts of data have been accumulated, the effect of TEs on the genome architecture and functioning is not fully understood. Here, plant genome organization was addressed by means of cloning and sequencing TE fragments of different types, which compose the largest portion of the Aegilops speltoides genome. Individual genotypes were analyzed cytogenetically using the cloned TE fragments as the DNA probes for fluorescence in situ hybridization (FISH). The obtained TE sequences of the Ty1-copia, Ty3-gypsy, LINE, and CACTA superfamilies showed the relatedness of the Ae. speltoides genome to the Triticeae tribe and similarities to evolutionarily distant species. A significant number of clones consisted of intercalated fragments of TEs of various types, in which Fatima (Ty3-gypsy) sequences predominated. At the chromosomal level, different TE clones demonstrated sequence-specific patterning, emphasizing the effect of the TE fraction on the Ae. speltoides genome architecture and intraspecific diversification. Altogether, the obtained data highlight the current species-specific organization and patterning of the mobile element fraction and point to ancient evolutionary events in the genome of Ae. speltoides.
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21
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Shams I, Raskina O. Intraspecific and intraorganismal copy number dynamics of retrotransposons and tandem repeat in Aegilops speltoides Tausch (Poaceae, Triticeae). PROTOPLASMA 2018; 255:1023-1038. [PMID: 29374788 DOI: 10.1007/s00709-018-1212-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 01/14/2018] [Indexed: 06/07/2023]
Abstract
Transposable elements (TE) and tandem repeats (TR) compose the largest fraction of the plant genome. The abundance and repatterning of repetitive DNA underlie intrapopulation polymorphisms and intraspecific diversification; however, the dynamics of repetitive elements in ontogenesis is not fully understood. Here, we addressed the genotype-specific and tissue-specific abundances and dynamics of the Ty1-copia, Ty3-gypsy, and LINE retrotransposons and species-specific Spelt1 tandem repeat in wild diploid goatgrass, Aegilops speltoides Tausch. Copy numbers of TEs and TR were estimated by real-time quantitative PCR in vegetative and generative tissues in original plants from contrasting allopatric populations and artificial intraspecific hybrids. The results showed that between leaves and somatic spike tissues as well as in progressive microsporogenesis of individual genotypes, the copy numbers of three TEs correlatively oscillated between 2- to 4-fold and the TR copy numbers fluctuated by 18- to 440-fold. Inter-individual and intraorganismal TEs and TR copy number dynamics demonstrate large-scale parallelism with extensive chromosomal rearrangements that were detected using fluorescent in situ hybridization in parental and hybrid genotypes. The data obtained indicate that tissue-specific differences in the abundance and pattern of repetitive sequences emerge during cell proliferation and differentiation in ontogenesis and reflect the reorganization of individual genomes in changing environments, especially in small peripheral population(s) under the influence of rapid climatic changes.
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Affiliation(s)
- Imad Shams
- Institute of Evolution and Department of Evolutionary and Environmental Biology, University of Haifa, Aba-Hushi Avenue 199, 3498838, Haifa, Mount Carmel, Israel
| | - Olga Raskina
- Institute of Evolution and Department of Evolutionary and Environmental Biology, University of Haifa, Aba-Hushi Avenue 199, 3498838, Haifa, Mount Carmel, Israel.
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22
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Kalendar R, Amenov A, Daniyarov A. Use of retrotransposon-derived genetic markers to analyse genomic variability in plants. FUNCTIONAL PLANT BIOLOGY : FPB 2018; 46:15-29. [PMID: 30939255 DOI: 10.1071/fp18098] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 08/23/2018] [Indexed: 06/09/2023]
Abstract
Transposable elements (TEs) are common mobile genetic elements comprising several classes and making up the majority of eukaryotic genomes. The movement and accumulation of TEs has been a major force shaping the genes and genomes of most organisms. Most eukaryotic genomes are dominated by retrotransposons and minimal DNA transposon accumulation. The 'copy and paste' lifecycle of replicative transposition produces new genome insertions without excising the original element. Horizontal TE transfer among lineages is rare. TEs represent a reservoir of potential genomic instability and RNA-level toxicity. Many TEs appear static and nonfunctional, but some are capable of replicating and mobilising to new positions, and somatic transposition events have been observed. The overall structure of retrotransposons and the domains responsible for the phases of their replication are highly conserved in all eukaryotes. TEs are important drivers of species diversity and exhibit great variety in their structure, size and transposition mechanisms, making them important putative actors in evolution. Because TEs are abundant in plant genomes, various applications have been developed to exploit polymorphisms in TE insertion patterns, including conventional or anchored PCR, and quantitative or digital PCR with primers for the 5' or 3' junction. Alternatively, the retrotransposon junction can be mapped using high-throughput next-generation sequencing and bioinformatics. With these applications, TE insertions can be rapidly, easily and accurately identified, or new TE insertions can be found. This review provides an overview of the TE-based applications developed for plant species and assesses the contributions of TEs to the analysis of plants' genetic diversity.
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Affiliation(s)
- Ruslan Kalendar
- Department of Agricultural Sciences, PO Box 27 (Latokartanonkaari 5), FI-00014 University of Helsinki, Helsinki, Finland
| | - Asset Amenov
- RSE 'National Center for Biotechnology', 13/5 Kurgalzhynskoye Road, Astana, 010000, Kazakhstan
| | - Asset Daniyarov
- RSE 'National Center for Biotechnology', 13/5 Kurgalzhynskoye Road, Astana, 010000, Kazakhstan
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23
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Domb K, Keidar D, Yaakov B, Khasdan V, Kashkush K. Transposable elements generate population-specific insertional patterns and allelic variation in genes of wild emmer wheat (Triticum turgidum ssp. dicoccoides). BMC PLANT BIOLOGY 2017; 17:175. [PMID: 29078757 PMCID: PMC5659041 DOI: 10.1186/s12870-017-1134-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Accepted: 10/17/2017] [Indexed: 05/02/2023]
Abstract
BACKGROUND Natural populations of the tetraploid wild emmer wheat (genome AABB) were previously shown to demonstrate eco-geographically structured genetic and epigenetic diversity. Transposable elements (TEs) might make up a significant part of the genetic and epigenetic variation between individuals and populations because they comprise over 80% of the wild emmer wheat genome. In this study, we performed detailed analyses to assess the dynamics of transposable elements in 50 accessions of wild emmer wheat collected from 5 geographically isolated sites. The analyses included: the copy number variation of TEs among accessions in the five populations, population-unique insertional patterns, and the impact of population-unique/specific TE insertions on structure and expression of genes. RESULTS We assessed the copy numbers of 12 TE families using real-time quantitative PCR, and found significant copy number variation (CNV) in the 50 wild emmer wheat accessions, in a population-specific manner. In some cases, the CNV difference reached up to 6-fold. However, the CNV was TE-specific, namely some TE families showed higher copy numbers in one or more populations, and other TE families showed lower copy numbers in the same population(s). Furthermore, we assessed the insertional patterns of 6 TE families using transposon display (TD), and observed significant population-specific insertional patterns. The polymorphism levels of TE-insertional patterns reached 92% among all wild emmer wheat accessions, in some cases. In addition, we observed population-specific/unique TE insertions, some of which were located within or close to protein-coding genes, creating allelic variations in a population-specific manner. We also showed that those genes are differentially expressed in wild emmer wheat. CONCLUSIONS For the first time, this study shows that TEs proliferate in wild emmer wheat in a population-specific manner, creating new alleles of genes, which contribute to the divergent evolution of homeologous genes from the A and B subgenomes.
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Affiliation(s)
- Katherine Domb
- Department of Life Sciences, Ben-Gurion University, 84105 Beer-Sheva, Israel
| | - Danielle Keidar
- Department of Life Sciences, Ben-Gurion University, 84105 Beer-Sheva, Israel
| | - Beery Yaakov
- Department of Life Sciences, Ben-Gurion University, 84105 Beer-Sheva, Israel
| | - Vadim Khasdan
- Department of Life Sciences, Ben-Gurion University, 84105 Beer-Sheva, Israel
| | - Khalil Kashkush
- Department of Life Sciences, Ben-Gurion University, 84105 Beer-Sheva, Israel
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24
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FastPCR: An in silico tool for fast primer and probe design and advanced sequence analysis. Genomics 2017; 109:312-319. [PMID: 28502701 DOI: 10.1016/j.ygeno.2017.05.005] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Revised: 05/09/2017] [Accepted: 05/11/2017] [Indexed: 01/16/2023]
Abstract
Polymerase chain reaction (PCR) is one of the most important laboratory techniques used in molecular biology, genetics and molecular diagnostics. The success of a PCR-based method largely depends on the correct nucleic acid sequence analysis in silico prior to a wet-bench experiment. Here, we report the development of an online Java-based software for virtual PCR on linear or circular DNA templates and multiple primer or probe search from large or small databases. Primer or probe sensitivity and specificity are predicted by searching a database to find sequences with an optimal number of mismatches, similarity and stability. The software determines primer location, orientation, efficiency of binding and calculates primer melting temperatures for standard and degenerate oligonucleotides. The software is suitable for batch file processing, which is essential for automation when working with large amounts of data. The online Java software is available for download at http://primerdigital.com/tools/pcr.html. Accession numbers for the sequences resulting from this study: EU140956 EU177767 EU867815 EU882730 FJ975775-FJ975780 HM481419 HM481420 KC686837-KC686839 KM262797.
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Abstract
The polymerase chain reaction (PCR) is fundamental to molecular biology and is the most important practical molecular technique for the research laboratory. The principle of this technique has been further used and applied in plenty of other simple or complex nucleic acid amplification technologies (NAAT). In parallel to laboratory "wet bench" experiments for nucleic acid amplification technologies, in silico or virtual (bioinformatics) approaches have been developed, among which in silico PCR analysis. In silico NAAT analysis is a useful and efficient complementary method to ensure the specificity of primers or probes for an extensive range of PCR applications from homology gene discovery, molecular diagnosis, DNA fingerprinting, and repeat searching. Predicting sensitivity and specificity of primers and probes requires a search to determine whether they match a database with an optimal number of mismatches, similarity, and stability. In the development of in silico bioinformatics tools for nucleic acid amplification technologies, the prospects for the development of new NAAT or similar approaches should be taken into account, including forward-looking and comprehensive analysis that is not limited to only one PCR technique variant. The software FastPCR and the online Java web tool are integrated tools for in silico PCR of linear and circular DNA, multiple primer or probe searches in large or small databases and for advanced search. These tools are suitable for processing of batch files that are essential for automation when working with large amounts of data. The FastPCR software is available for download at http://primerdigital.com/fastpcr.html and the online Java version at http://primerdigital.com/tools/pcr.html .
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Ochoa Cruz EA, Cruz GMQ, Vieira AP, Van Sluys MA. Virus-like attachment sites as structural landmarks of plants retrotransposons. Mob DNA 2016; 7:14. [PMID: 27471551 PMCID: PMC4963935 DOI: 10.1186/s13100-016-0069-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 07/07/2016] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND The genomic data available nowadays has enabled the study of repetitive sequences and their relationship to viruses. Among them, long terminal repeat retrotransposons (LTR-RTs) are the largest component of most plant genomes, the Gypsy and Copia superfamilies being the most common. Recently it has been found that Del lineage, an LTR-RT of Gypsy superfamily, has putative virus-like attachment (vl-att) sites. This signature, originally described for retroviruses, is recognized by retroviral integrase conferring specificity to the integration process. RESULTS Here we retrieved 26,092 putative complete LTR-RTs from 10 lineages found in 10 fully sequenced angiosperm genomes and found putative vl-att sites that are a conserved structural landmark across these genomes. Furthermore, we reveal that each plant genome has a distinguishable LTR-RT lineage amplification pattern that could be related to the vl-att sites diversity. We used these patterns to generate a specific quick-response (QR) code for each genome that could be used as a barcode of identification of plants in the future. CONCLUSIONS The universal distribution of vl-att sites represents a new structural feature common to plant LTR-RTs and retroviruses. This is an important finding that expands the information about the structural similarity between LTR-RT and retroviruses. We speculate that the sequence diversity of vl-att sites could be important for the life cycle of retrotransposons, as it was shown for retroviruses. All the structural vl-att site signatures are strong candidates for further functional studies. Moreover, this is the first identification of specific LTR-RT content and their amplification patterns in a large dataset of LTR-RT lineages and angiosperm genomes. These distribution patterns could be used in the future with biotechnological identification purposes.
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Affiliation(s)
- Edgar Andres Ochoa Cruz
- Departamento de Botânica, Instituto de Biociências (IB), Universidade de São Paulo (USP), 05508-090 São Paulo, SP Brasil
| | | | - Andréia Prata Vieira
- Departamento de Botânica, Instituto de Biociências (IB), Universidade de São Paulo (USP), 05508-090 São Paulo, SP Brasil
| | - Marie-Anne Van Sluys
- Departamento de Botânica, Instituto de Biociências (IB), Universidade de São Paulo (USP), 05508-090 São Paulo, SP Brasil
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Belyayev A. Bursts of transposable elements as an evolutionary driving force. J Evol Biol 2014; 27:2573-84. [PMID: 25290698 DOI: 10.1111/jeb.12513] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 09/17/2014] [Accepted: 09/17/2014] [Indexed: 12/25/2022]
Abstract
A burst of transposable elements (TEs) is a massive outbreak that may cause radical genomic rebuilding. This phenomenon has been reported in connection with the formation of taxonomic groups and species and has therefore been associated with major evolutionary events in the past. Over the past few years, several research groups have discovered recent stress-induced bursts of different TEs. The events for which bursts of TEs have been recorded include domestication, polyploidy, changes in mating systems, interspecific and intergeneric hybridization and abiotic stress. Cases involving abiotic stress, particularly bursts of TEs in natural populations driven by environmental change, are of special interest because this phenomenon may underlie micro- and macro-evolutionary events and ultimately support the maintenance and generation of biological diversity. This study reviews the known cases of bursts of TEs and their possible consequences, with particular emphasis on the speciation process.
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Affiliation(s)
- A Belyayev
- Institute of Botany, Czech Academy of Sciences, Pruhonice near Prague, Czech Republic
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Ruban A, Fuchs J, Marques A, Schubert V, Soloviev A, Raskina O, Badaeva E, Houben A. B chromosomes of Aegilops speltoides are enriched in organelle genome-derived sequences. PLoS One 2014; 9:e90214. [PMID: 24587288 PMCID: PMC3936023 DOI: 10.1371/journal.pone.0090214] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 01/27/2014] [Indexed: 11/19/2022] Open
Abstract
B chromosomes (Bs) are dispensable components of the genome exhibiting non-Mendelian inheritance. Chromosome counts and flow cytometric analysis of the grass species Aegilops speltoides revealed a tissue-type specific distribution of the roughly 570 Mbp large B chromosomes. To address the question whether organelle-to-nucleus DNA transfer is a mechanism that drives the evolution of Bs, in situ hybridization was performed with labelled organellar DNA. The observed B-specific accumulation of chloroplast- and mitochondria-derived sequences suggests a reduced selection against the insertion of organellar DNA in supernumerary chromosomes. The distribution of B-localised organellar-derived sequences and other sequences differs between genotypes of different geographical origins.
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Affiliation(s)
- Alevtina Ruban
- Russian State Agrarian University – Moscow Timiryazev Agricultural Academy, Department of Genetics and Biotechnology, Moscow, Russia
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Chromosome Structure and Function Laboratory, Gatersleben, Germany
| | - Jörg Fuchs
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Chromosome Structure and Function Laboratory, Gatersleben, Germany
| | - André Marques
- Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Universidade Federal de Pernambuco, Recife, Brazil
| | - Veit Schubert
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Chromosome Structure and Function Laboratory, Gatersleben, Germany
| | - Alexander Soloviev
- Russian State Agrarian University – Moscow Timiryazev Agricultural Academy, Department of Genetics and Biotechnology, Moscow, Russia
| | - Olga Raskina
- Institute of Evolution, University of Haifa, Laboratory of Plant Molecular Cytogenetics, Haifa, Israel
| | - Ekaterina Badaeva
- Engelhardt Institute of Molecular Biology Russian Academy of Sciences, Laboratory of Molecular Karyology, Moscow, Russia
| | - Andreas Houben
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Chromosome Structure and Function Laboratory, Gatersleben, Germany
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Yaakov B, Meyer K, Ben-David S, Kashkush K. Copy number variation of transposable elements in Triticum-Aegilops genus suggests evolutionary and revolutionary dynamics following allopolyploidization. PLANT CELL REPORTS 2013; 32:1615-24. [PMID: 23807536 DOI: 10.1007/s00299-013-1472-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 06/12/2013] [Accepted: 06/12/2013] [Indexed: 05/02/2023]
Abstract
Here, we report on copy number variation of transposable elements and on the genome-specific proliferation in wheat. In addition, we report on revolutionary and evolutionary dynamics of transposons. Wheat is a valuable model for understanding the involvement of transposable elements (TEs) in speciation as wheat species (Triticum-Aegilops group) have diverged from a common ancestor, have undergone two events of speciation through allopolyploidy, and contain a very high fraction of TEs. However, an unbiased genome-wide examination of TE variation among these species has not been conducted. Our research utilized quantitative real time PCR to assess the relative copy numbers of 16 TE families in various Triticum and Aegilops species. We found (1) high variation and genome-specificity of TEs in wheat species, suggesting they were active throughout the evolution of wheat, (2) neither Ae. searsii nor Ae. speltoides by themselves can be the only contributors of the B genome to wheat, and (3) nonadditive changes in TE quantities in polyploid wheat. This study indicates the apparent involvement of large TEs in creating genetic variation in revolutionary and evolutionary scales following allopolyploidization events, presumably assisting in the diploidization of homeologous chromosomes.
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Affiliation(s)
- Beery Yaakov
- Department of Life Sciences, Ben-Gurion University, Beer-Sheva, 84105, Israel
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Bleykasten-Grosshans C, Friedrich A, Schacherer J. Genome-wide analysis of intraspecific transposon diversity in yeast. BMC Genomics 2013; 14:399. [PMID: 23768249 PMCID: PMC4022208 DOI: 10.1186/1471-2164-14-399] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 06/06/2013] [Indexed: 02/02/2023] Open
Abstract
Background In the model organism Saccharomyces cerevisiae, the transposable elements (TEs) consist of LTR (Long Terminal Repeat) retrotransposons called Ty elements belonging to five families, Ty1 to Ty5. They take the form of either full-length coding elements or non-coding solo-LTRs corresponding to remnants of former transposition events. Although the biological features of Ty elements have been studied in detail in S. cerevisiae and the Ty content of the reference strain (S288c) was accurately annotated, the Ty-related intra-specific diversity has not been closely investigated so far. Results In this study, we investigated the Ty contents of 41 available genomes of isolated S. cerevisiae strains of diverse geographical and ecological origins. The strains were compared in terms of the number of Ty copies, the content of the potential transpositionally active elements and the genomic insertion maps. The strain repertoires were also investigated in the closely related Ty1 and Ty2 families and subfamilies. Conclusions This is the first genome-wide analysis of the diversity associated to the Ty elements, carried out for a large set of S. cerevisiae strains. The results of the present analyses suggest that the current Ty-related polymorphism has resulted from multiple causes such as differences between strains, between Ty families and over time, in the recent transpositional activity of Ty elements. Some new Ty1 variants were also identified, and we have established that Ty1 variants have different patterns of distribution among strains, which further contributes to the strain diversity.
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Affiliation(s)
- Claudine Bleykasten-Grosshans
- CNRS, Department of Genetics, Genomics and Microbiology, University of Strasbourg, UMR 7156, 28, rue Goethe, Strasbourg, 67083, France.
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