ABSTRACT
In an attempt to understand the dynamics of transposable elements (T'S) in the genome of host species, we investigated the distribution, representativeness and conservation of DNA sequences homologous to the Drosophila melanogaster gypsy retrotransposon in 42 drosophilid species. Our results extended the knowledge about the wide distribution of gypsy in the genus Drosophila, including several Neotropical species not previously studied. The gypsy-like sequences showed high divergence compared to the D. melanogaster gypsy element. Furthermore, the conservation of the restriction sites between gypsy sequences from phylogenetically unrelated species pointed to a more complex evolutionary picture, which includes the possibility of the horizontal transfer events already described for this retrotransposon.
ABSTRACT
In an endeavor to contribute to the comprehension of the evolution of transposable elements (TEs) in the genome of host species, we investigated the phylogenetic relationships of sequences homologous to the retrotransposon gypsy of Drosophila melanogaster in 19 species of Drosophila, in Scaptodrosophila latifasciaeformis, and in Zaprionus indianus. This phylogenetic study was based on approximately 500 base pairs of the env gene. Our analyses showed considerable discrepancy between the phylogeny of gypsy elements and the relationship of their host species, and they allow us to infer a complex evolutionary pattern that could include ancestral polymorphism, vertical transmission, and several cases of horizontal transmission.
