Activation of the Ty1-copia group retrotransposons of potato (Solatium tuberosum) during protoplast isolation.

The potato (Solanum tuberosum) genome contains a highly heterogeneous population of Ty1-copia group retrotransposons. Here we identify the first such transposable element known to be transcribed in this species. The elements are transcriptionally activated during protoplast isolation. The majority of the activated Ty1-copia sequences are similar to elements which are transcriptionally induced under the same conditions in tobacco (Nicotiana tabacum). We also show that a previously identified potato element M166, which has no known equivalent in tobacco is also transcribed under these conditions. It appears that the control of transcription of this particular Ty1-copia group retrotransposons has been broadly conserved between these two species.