Toxoplasma gondii antigen production in tobacco leaves

FERRARO, G., ANGEL, S. O., ZELADA, A., MENTABERRY, A. N. AND CLEMENTE, M

Pinamar, Argentina

Congreso; XLI Annual Meeting of the Argentine Society for Biochemistry and Molecular Biology (SAIB); 2005

SAIB

We adapted a previously described Agrobacterium-mediated transient expression system to test the expression level of two antigenic proteins of T. gondii: dense granule 4 (Gra4) and serin proteinase (TgPI). We used two different strategies for plant expression cassette construction to determine which of them represents the best choice to generate transgenic plants in the future. One construct was based in the PVX amplicon, where each gene was placed under the control of an additional coat protein subgenomic promoter. In the other construct each gene was fused to an apoplastic peptide signal under the CaMV 35S promoter. T. gondii antigen expression levels in tobacco leaves were quantified by Western blot using E. coli-expressed these antigens as control. Depending on the expression cassette used and the antigen expressed, the antigen yields in leaves infiltrated ranged from 0.2% to 0.01 % of total soluble protein. Gra4-expressing leaves showed the highest expression levels. The Gra4 and TgPI accumulation levels were higher with the amplicon PVX. Gra4 and TgPI will be included in future studies to evaluate the biological activity of these recombinant proteins