Floral-dip transformation of Arabidopsis thaliana to examine pTSO2::beta-glucuronidase reporter gene expression.

The ability to introduce foreign genes into an organism is the foundation for modern biology and biotechnology. In the model flowering plant Arabidopsis thaliana, the floral-dip transformation method has replaced all previous methods because of its simplicity, efficiency, and low cost. Specifically, shoots of young flowering Arabidopsis plants are dipped in a solution of Agrobacterium tumefaciens carrying specific plasmid constructs. After dipping, the plants are returned to normal growth and yield seeds, a small percentage of which are transformed with the foreign gene and can be selected for on medium containing antibiotics. This floral-dip method significantly facilitated Arabidopsis research and contributed greatly to our understanding of plant gene function. In this study, we use the floral-dip method to transform a reporter gene, beta-glucuronidase (GUS), under the control of TSO2 promoter. TSO2, coding for the Ribonucleotide Reductase (RNR) small subunit, is a cell cycle regulated gene essential for dNDP biosynthesis in the S-phase of the cell cycle. Examination of GUS expression in transgenic Arabidopsis seedlings shows that TSO2 is expressed in actively dividing tissues. The reported experimental method and materials can be easily adapted not only for research but also for education at high school and college levels.