Abstract
Public concerns about the issue of the environmental safety of genetically modified plants have led to a demand for technologies allowing the production of transgenic plants without selectable (antibiotic resistance) markers. We describe the development of an effective transformation system for generating such marker-free transgenic plants, without the need for repeated transformation or sexual crossing. This system combines an inducible site-specific recombinase for the precise elimination of undesired, introduced DNA sequences with a bifunctional selectable marker gene used for the initial positive selection of transgenic tissue and subsequent negative selection for fully marker-free plants. The described system can be generally applied to existing transformation protocols, and was tested in strawberry using a model vector in which site-specific recombination leads to a functional combination of a cauliflower mosaic virus 35S promoter and a GUS encoding sequence, thereby enabling the histochemical monitoring of recombination events. Fully marker-free transgenic strawberry plants were obtained following two different selection/regeneration strategies.
Original language | English |
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Pages (from-to) | 233-240 |
Journal | Plant Biotechnology Journal |
Volume | 2 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2004 |
Keywords
- cytosine deaminase
- glucocorticoid receptor
- transformation vector
- negative selection
- bacterial gene
- expression
- agrobacterium
- regeneration
- system
- frequency