Influence of a Mammalian 2'-5' A Oligoadenylate Synthetase Transgene on Tobacco Resistance to <em>Potato virus X</em> Infection

Abstract

The effect of human 2’-5’ A oligoadenylate synthethase transgene against Potato virus X (PVX) infection in tobacco plants was studied. To the purpose, leaf tissues of cv. Samsun were transformed via Agrobacterium tumefaciens LB 4404 carrying a modified PBI121 binary vector deprived of GUS and containing the transgene. Seventy-five percent of R1 derived seeds germinated on kanamycin selective medium, indicating the transgene integration in a single locus. The virus resistance of R1 plantlets was tested by mechanical inoculation with purified suspension of different virus concentration (1, 0.1, and 0.05 mg ml-1). Only plants inoculated with the lowest PVX concentration, showed a reduced virus content (43% that of controls) 20 days after inoculation. This result renders the practical utility of the gene doubtful.