tailieunhanh - Báo cáo y học: "Widespread evidence for horizontal transfer of transposable elements across Drosophila genomes"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Minireview cung cấp cho các bạn kiến thức về ngành y đề tài: Widespread evidence for horizontal transfer of transposable elements across Drosophila genomes. | Open Access Researc h Widespread evidence for horizontal transfer of transposable elements across Drosophila genomes Carolina Bartolomé Xabier Bello and Xulio Maside Address Dpto de Anatomía Patolóxica e Ciencias Forenses Grupo de Medicina Xenómica-CIBERER Universidade de Santiago de Compostela Rúa de San Francisco s n Santiago de Compostela 15782 Spain. Correspondence Xulio Maside. Email Published 18 February 2009 Received 17 December 2008 Genome Biology 2009 I0 R22 doi gb-2009- 10-2-r22 Accepted 18 February 2009 The electronic version of this article is the complete one and can be found online at http 2009 10 2 R22 2009 Bartolomé et al. licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract Background Horizontal transfer HT could play an important role in the long-term persistence of transposable elements TEs because it provides them with the possibility to avoid the checking effects of host-silencing mechanisms and natural selection which would eventually drive their elimination from the genome. However despite the increasing evidence for HT of TEs its rate of occurrence among the TE pools of model eukaryotic organisms is still unknown. Results We have extracted and compared the nucleotide sequences of all potentially functional autonomous TEs present in the genomes of Drosophila melanogaster D. simulans and D. yakuba -1 436 insertions classified into 141 distinct families - and show that a large fraction of the families found in two or more species display levels of genetic divergence and within-species diversity that are significantly lower than expected by assuming copy-number equilibrium and vertical transmission and consistent with a recent origin by HT. Long terminal