Germline transformation of <i>Drosophila melanogaster</i> with the <i>piggyBac</i> transposon vector

Abstract Germline transformation of Drosophila melanogaster was attempted with the piggyBac gene‐transfer system from the cabbage looper moth, Trichoplusia ni . Using a self‐regulated transposase helper and a white marked vector, a transformation frequency of 1–3% per fertile G0 was obtained, similar to that previously achieved in the medfly. Use of an hsp70 ‐regulated helper increased this frequency more than eight‐fold. Transformation with a vector marked with white and green fluorescent protein (GFP) under polyubiquitin–nuclear localizing sequence regulation yielded seventy G1 transformants which all expressed GFP, but only twenty‐seven of these expressed eye pigmentation that would have allowed their selection based on white + expression. PiggyBac transformation in two distantly related dipteran species and efficient expression of the gfp marker supports the potential use of this system in other dipterans, and perhaps insects in general.