Drosophila mediopunctata P elements: a new example of horizontal transfer.
Sequences homologous to the P element of Drosophila melanogaster were previously identified in Drosophila mediopunctata, a member of the tripunctata group, subgenus Drosophila. We report here that the P element is present in about three to five copies in the D. mediopunctata genome. While one of the insertion sites appears to be fixed, others may be polymorphic, indicating relatively recent P element activity. Phylogenetic analysis revealed that the D. mediopunctata element belongs to the canonical subfamily of P elements and that divergence of the D. mediopunctata element from other members of this subfamily ranges from 2% to 5% at the nucleotide level. This is the first report of a canonical P element outside the subgenus Sophophora. Based primarily on the striking incongruence between P element and host species phylogenies, the presence of a canonical P element in D. mediopunctata is most likely explained by horizontal transfer between species.
Loreto
E L
EL
Departmento de Biologia, Universidade Federal de Santa Maria, CEP 97105-900, Santa Maria, RS, Brazil.
Valente
V L
VL
Zaha
A
A
Silva
J C
JC
Kidwell
M G
MG
D000818:Animals; D015139:Blotting, Southern; D004251:DNA Transposable Elements; D004330:Drosophila / Q000145:classification / Q000235:genetics*; D018628:Gene Dosage; D022761:Gene Transfer, Horizontal; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013045:Species Specificity
D004251:DNA Transposable Elements