Distribution of the transposable element Minos in the genus Drosophila

We analyzed 28 species of the genus Drosophila for the presence of the Tc1-like transposable element Minos using Southern blot hybridization under high stringency conditions. The Minos transposon was found in members of both the Drosophila and the Sophophora subgenus showing a distribution that is wider if compared to other well-studied Drosophila transposons such as the P element, hobo and mariner. The presence of Minos-hybridizing sequences was discontinuous in the Sophophora subgenus, especially in the melanogaster species group. Using the Polymerase Chain Reaction we amplified a portion corresponding to the putative Minos transposase from different Drosophila species. Cloning and sequence analysis of randomly selected Minos copies from D. mojavensisis, D. saltans and D. willistoni supports the idea that event(s) of horizontal transfer may have contributed to the spreading of this transposon in the Drosophila genus.