Analysis of T-DNA insertion in transgenic Del/Ros1 tomato by genome resequencing

Cathie Martin and Eugenio Butelli introduced into tomato (Solanum lycopersicum) two genes that increase the levels of two types of anthocynanin in tomato fruit, as well as some minor types. These anthocyanins, delphinidin 3-O-(coumaroyl) rutinoside-5-O-glucoside, and petunidin 3-O-(coumaroyl) rutinoside-5-O-glucoside, are the same as those expressed in tomato leaves to protect them from light stress. These two anthocyanins are also found in the skin of tomato fruit resulting from crosses of Solanum lycopersicum (cultivated tomato) to the wild species Solanum chilense and Solanum cheesmaniae and currently available to consumers as the commercial tomato varieties Indigo Rose and Sunblack. The transformation event Del/Ros1-N carries a single T-DNA insertion in the tomato (MicroTom) genetic background, as described by Butelli et al, (2008). DNA was prepared from a T6 generation plant carrying this T-DNA for resequencing. This was undertaken to establish:1) Whether there were any vector flanking sequences in the genome of Del/Ros1-N2) Whether the sequences encoding the Del and Ros1 transcription factor transgenes were exactly the same as in the pDEL.ROS vector used for transformation.No sequences identical to the pRK290 vector backbone were identified in the Del/Ros1-N genome sequence. No mutations existed in the Del and Ros1 transgenes in the Del/Ros1-N event.