Widespread evidence for horizontal transfer of transposable elements across Drosophila genomes

Carolina Bartolomé,Xulio Maside,Xabier Bello

doi:10.1186/gb-2009-10-2-r22

Carolina Bartolomé, Xulio Maside + Show 1 more

Open Access

https://doi.org/10.1186/gb-2009-10-2-r22

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Journal: Genome Biology	Publication Date: Jan 1, 2009
Citations: 200	License type: cc-by

Affiliation: University of Santiago de Compostela

Abstract

A genome-wide comparison of transposable elements reveals evidence for unexpectedly high rates of horizontal transfer between three species of Drosophila

Highlights

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
For between-species comparisons, we needed to distinguish 'orthologous' families - that is, those derived from a single family that was active in the two species' most recent common ancestor by the time of their split, or later transmitted by HT between the two species - from 'paralogous' families, originated by differentiation of TE lineages in the species' common ancestor prior to their split, or by HT from species other than those included in this study
That dataset can be used as an external quality control: out of the 28 possible between species comparisons (14 D. melanogaster TEs compared with their orthologues from D. simulans and D. yakuba) we found five minor discrepancies between the two approaches, which do not affect the overall results

Summary

Introduction

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. Loreto et al [26] gathered evidence for over 100 cases of HT of TEs across Drosophila species Methodological issues such as ascertainment bias (for example, the use of TE detection methods based on sequence homology, such as PCR or nucleotide sequence comparisons, or the preferential study of young active TE families) mean that this catalogue of HT cases cannot be used as a reference for the relative importance of such events in the evolutionary biology of the pool of active elements in a given genome

Methods

Results

Conclusion