19 research outputs found

    The impact of Ty3-gypsy group LTR retrotransposons Fatima on B-genome specificity of polyploid wheats

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    <p>Abstract</p> <p>Background</p> <p>Transposable elements (TEs) are a rapidly evolving fraction of the eukaryotic genomes and the main contributors to genome plasticity and divergence. Recently, occupation of the A- and D-genomes of allopolyploid wheat by specific TE families was demonstrated. Here, we investigated the impact of the well-represented family of <it>gypsy </it>LTR-retrotransposons, <it>Fatima</it>, on B-genome divergence of allopolyploid wheat using the fluorescent <it>in situ </it>hybridisation (FISH) method and phylogenetic analysis.</p> <p>Results</p> <p>FISH analysis of a BAC clone (BAC_2383A24) initially screened with Spelt1 repeats demonstrated its predominant localisation to chromosomes of the B-genome and its putative diploid progenitor <it>Aegilops speltoides </it>in hexaploid (genomic formula, BBAADD) and tetraploid (genomic formula, BBAA) wheats as well as their diploid progenitors. Analysis of the complete BAC_2383A24 nucleotide sequence (113 605 bp) demonstrated that it contains 55.6% TEs, 0.9% subtelomeric tandem repeats (Spelt1), and five genes. LTR retrotransposons are predominant, representing 50.7% of the total nucleotide sequence. Three elements of the <it>gypsy </it>LTR retrotransposon family <it>Fatima </it>make up 47.2% of all the LTR retrotransposons in this BAC. <it>In situ </it>hybridisation of the <it>Fatima</it>_2383A24-3 subclone suggests that individual representatives of the <it>Fatima </it>family contribute to the majority of the B-genome specific FISH pattern for BAC_2383A24. Phylogenetic analysis of various <it>Fatima </it>elements available from databases in combination with the data on their insertion dates demonstrated that the <it>Fatima </it>elements fall into several groups. One of these groups, containing <it>Fatima</it>_2383A24-3, is more specific to the B-genome and proliferated around 0.5-2.5 MYA, prior to allopolyploid wheat formation.</p> <p>Conclusion</p> <p>The B-genome specificity of the <it>gypsy</it>-like <it>Fatima</it>, as determined by FISH, is explained to a great degree by the appearance of a genome-specific element within this family for <it>Ae. speltoides</it>. Moreover, its proliferation mainly occurred in this diploid species before it entered into allopolyploidy.</p> <p>Most likely, this scenario of emergence and proliferation of the genome-specific variants of retroelements, mainly in the diploid species, is characteristic of the evolution of all three genomes of hexaploid wheat.</p

    Isolation and sequence analysis of the wheat B genome subtelomeric DNA

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    <p>Abstract</p> <p>Background</p> <p>Telomeric and subtelomeric regions are essential for genome stability and regular chromosome replication. In this work, we have characterized the wheat BAC (bacterial artificial chromosome) clones containing Spelt1 and Spelt52 sequences, which belong to the subtelomeric repeats of the B/G genomes of wheats and <it>Aegilops </it>species from the section <it>Sitopsis</it>.</p> <p>Results</p> <p>The BAC library from <it>Triticum aestivum </it>cv. Renan was screened using Spelt1 and Spelt52 as probes. Nine positive clones were isolated; of them, clone 2050O8 was localized mainly to the distal parts of wheat chromosomes by <it>in situ </it>hybridization. The distribution of the other clones indicated the presence of different types of repetitive sequences in BACs. Use of different approaches allowed us to prove that seven of the nine isolated clones belonged to the subtelomeric chromosomal regions. Clone 2050O8 was sequenced and its sequence of 119 737 bp was annotated. It is composed of 33% transposable elements (TEs), 8.2% Spelt52 (namely, the subfamily Spelt52.2) and five non-TE-related genes. DNA transposons are predominant, making up 24.6% of the entire BAC clone, whereas retroelements account for 8.4% of the clone length. The full-length CACTA transposon <it>Caspar </it>covers 11 666 bp, encoding a transposase and CTG-2 proteins, and this transposon accounts for 40% of the DNA transposons. The <it>in situ </it>hybridization data for 2050O8 derived subclones in combination with the BLAST search against wheat mapped ESTs (expressed sequence tags) suggest that clone 2050O8 is located in the terminal bin 4BL-10 (0.95-1.0). Additionally, four of the predicted 2050O8 genes showed significant homology to four putative orthologous rice genes in the distal part of rice chromosome 3S and confirm the synteny to wheat 4BL.</p> <p>Conclusion</p> <p>Satellite DNA sequences from the subtelomeric regions of diploid wheat progenitor can be used for selecting the BAC clones from the corresponding regions of hexaploid wheat chromosomes. It has been demonstrated for the first time that Spelt52 sequences were involved in the evolution of terminal regions of common wheat chromosomes. Our research provides new insights into the microcollinearity in the terminal regions of wheat chromosomes 4BL and rice chromosome 3S.</p

    Economic Migration in Central Siberia and Ethnic Conflict Risks (Based on Krasnoyarsk Krai Analysis)

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    Migration, be it free or forced, is an essential prerequisite of the dynamic development of many territories, Krasnoyarsk Krai inclusive. The territory of the region is irregularly and poorly populated: 84% of inhabitants are concentrated in the south of the region, in the territory comprising only 10% of the regional territory. Under the circumstances Krasnoyarsk Krai needs an increased flow of migrants for the participation in economic development of unpopulated areas of Krai. But on the other hand, economic need in migrants becomes the reason of the ethnic conflicts risks increase in Central Siberia through creation of various negative myths on migrants. The experts report an increase in social tension between migrants and host parties in the Siberian regions of the Russian Federation. The interrelations inside the social medium and cultural contacts are in many respects determinant for the economic development of the region because the main actors of the economics are people. Keywords: economic migration, tolerance index, Siberia, Krasnoyarsk Krai JEL Classifications: D8, R1, Z

    Влияние климатических условий на традиционную экономику коренных малочисленных народов, проживающих в Эвенкийском муниципальном районе (Красноярский край)

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    At present the climate problem is one of the most relevant and discussed in various contexts. The article raises a problem of the interconnection between climatic conditions and the implementation of traditional forms of the economy management by the indigenous inhabitants of the Evenkiysky Municipal District of the Krasnoyarsk Territory. Based on the results of the field research, interviewing of experts and application of the Delphi survey method, the authors make conclusions about the current state of the traditional economy of the indigenous small-numbered peoples of the North of the Krasnoyarsk Territory and the impact of climatic conditions on it, and provide forecasts on the prospects for the development of traditional forms of the economy management (reindeer breeding, hunting, fishing, wild plant gathering) taking into account the influence of climatic conditions and their dynamicsПроблема климата на сегодняшний день является одной из самых актуальных и обсуждаемых в различных контекстах. В настоящей статье поднимается проблема взаимосвязи климатических условий и осуществления традиционных форм хозяйствования коренными жителями Эвенкийского муниципального района Красноярского края. На основе результатов полевых исследований, интервьюирования экспертов и применения метода Дельфи-опроса сделаны выводы о современном состоянии традиционной экономики коренных малочисленных народов Севера Красноярского края и влиянии на нее климатических условий, а также представлены прогнозы о перспективах развития традиционных форм хозяйствования (оленеводства, охоты, рыбной ловли, сбора дикоросов) с учетом влияния климатических условий и их динамик

    Влияние климатических условий на традиционную экономику коренных малочисленных народов, проживающих в Эвенкийском муниципальном районе (Красноярский край)

    No full text
    At present the climate problem is one of the most relevant and discussed in various contexts. The article raises a problem of the interconnection between climatic conditions and the implementation of traditional forms of the economy management by the indigenous inhabitants of the Evenkiysky Municipal District of the Krasnoyarsk Territory. Based on the results of the field research, interviewing of experts and application of the Delphi survey method, the authors make conclusions about the current state of the traditional economy of the indigenous small-numbered peoples of the North of the Krasnoyarsk Territory and the impact of climatic conditions on it, and provide forecasts on the prospects for the development of traditional forms of the economy management (reindeer breeding, hunting, fishing, wild plant gathering) taking into account the influence of climatic conditions and their dynamicsПроблема климата на сегодняшний день является одной из самых актуальных и обсуждаемых в различных контекстах. В настоящей статье поднимается проблема взаимосвязи климатических условий и осуществления традиционных форм хозяйствования коренными жителями Эвенкийского муниципального района Красноярского края. На основе результатов полевых исследований, интервьюирования экспертов и применения метода Дельфи-опроса сделаны выводы о современном состоянии традиционной экономики коренных малочисленных народов Севера Красноярского края и влиянии на нее климатических условий, а также представлены прогнозы о перспективах развития традиционных форм хозяйствования (оленеводства, охоты, рыбной ловли, сбора дикоросов) с учетом влияния климатических условий и их динамик
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