Maintenance of the Drosophila melanogaster genomic fragment harbouring the mdg4 copia-like retrotransposon in tobacco cells.

Recent experiments have revealed that plant genomes contain genetic elements closely related to well-known yeast and Drosophila retrotransposons. In connection with these findings we decided to test the behaviour of one of the well-defined Drosophila retrotransposons in tobacco cells. The copia-like Drosophila melanogaster retrotransposon mdg4 was introduced into Nicotiana tabacum and Nicotiana plumbaginifolia cells using a Ti plasmid vector. The results showed that entire copies of mdg4, as part of pTiC58 T-DNA, were stably maintained in tobacco cells upon continuous culturing of transformed tumour lines on hormone-free medium. Transcription of mdg4 from its LTR promoter was not detectable in tobacco cells.