Evolution of Tom, 297, 17.6 and rover retrotransposons in Drosophilidae species |
| |
Authors: | Newton Medeiros Vidal Adriana Ludwig and Elgion Lucio Silva Loreto |
| |
Abstract: | LTR retrotransposons are the most abundant transposable elements in Drosophila and are believed to have contributed significantly to genome evolution. Different reports have shown that many LTR retrotransposon
families in Drosophila melanogaster emerged from recent evolutionary episodes of transpositional activity. To contribute to the knowledge of the evolutionary
history of Drosophila LTR retrotransposons and the mechanisms that control their abundance, distribution and diversity, we conducted analyses of
four related families of LTR retrotransposons, 297, 17.6, rover and Tom. Our results show that these elements seem to be restricted to species from the D. melanogaster group, except for 17.6, which is also present in D. virilis and D. mojavensis. Genetic divergences and phylogenetic analyses of a 1-kb fragment region of the pol gene illustrate that the evolutionary dynamics of Tom, 297, 17.6 and rover retrotransposons are similar in several aspects, such as low codon bias, the action of purifying selection and phylogenies
that are incongruent with those of the host species. We found an extremely complex association among the retrotransposon sequences,
indicating that different processes shaped the evolutionary history of these elements, and we detected a very high number
of possible horizontal transfer events, corroborating the importance of lateral transmission in the evolution and maintenance
of LTR retrotransposons. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|