INTRODUCTION OF THE TRANSPOSABLE ELEMENT MINOS INTO THE GERM-LINE OF DROSOPHILA-MELANOGASTER

A transposon based on the transposable element Mines from Drosophila h ydei was introduced into the genome of Drosophila melanogaster using t ransformation mediated by the Mines transposase. The transposon carrie s a wild-type version of the white gene (w) of Drosophila inserted int o the second exon of Mines, Transformation was obtained by injecting t he transposon into preblastoderm embryos that were expressing transpos ase either from a Hsp70-Mines fusion inserted into the genome via P-el ement-mediated transformation or from a coinjected plasmid carrying th e Hsp70-Mines fusion. Between 1% and 6% of the fertile injected indivi duals gave transformed progeny. Four of the insertions were cloned and the DNA sequences flanking the transposon ends were determined. The ' 'empty'' sites corresponding to three of the insertions were amplified from the recipient strain by PCR, cloned, and sequenced, In all cases , the transposon has inserted into a TA dinucleotide and has created t he characteristic TA target site duplication. In the absence of transp osase, the insertions were: stable in the soma and the germ line. Howe ver, in the presence of the Hsp70-Minos gene the Minos-w transposon ex cises, resulting in mosaic eyes and germ-line reversion to the white p henotype. Mines could be utilized as an alternative to existing system s for transposon tagging and enhancer trapping in Drosophila; it might also be of use as a germ-line transformation vector for non-Drosophil a insects.