Beneficial Microbes: Food, Pharma, Aqua & Beverages Industry

Most genetic engineering of plants uses Agrobacterium mediated transformation to introduce novel gene content. In nature,

insertion of T-DNA in the plant genome and its subsequent transfer via sexual reproduction has been shown in several

species in the genera Nicotiana, Ipomea and Linaria. Th ey are called naturally transgenic plant. A sequence homologous to the

T-DNA of the Ri plasmid of Agrobacterium rhizogenes was found in the genome of untransformed Nicotiana glauca about 30

years ago and was named “cellular T-DNA” (cT-DNA). A similar cT-DNA has also been found in other species of the genus

Nicotiana. In our study T-DNA-like sequences has been detected and characterized in diff erent Linaria species, belonging to

two sections Linaria and Speciosa. In all characterized Linaria species the cT-DNA is present in two copies and organized as

a tandem imperfect direct repeat and contained the same T-DNA oncogenes and the mis gene, however there are diff erent

mutations inside the T-DNA in the investigated forms. Linaria species are medicinal transgenic plants that people used for

ages. Characterization of structure of T-DNA in close species of naturally transgenic plants is important, since they could be

good model system for study of delayed environmental risks of GMO.