RESUMO
TA3-13 is a truncated gene coding for the fragment of wheat (Triticum aestivum L.) cold shock protein WCP1. It has been shown previously that the procaryotically expressed TA3-13 can induce resistance to Tobacco mosaic virus (TMV) when sprayed onto plant leaves. In this study, we constructed an expression vector pB-3-13 by cloning TA3-13 into the bionary vector pBI121 and transformed it into Agrobacterium tumefaciense strain EHA105 via freeze-thaw method. Tobacco (Nicotiana tobacum cv. Xanthi nc.) transformation was performed using the leaf disc infection method. After screening on MS medium containing kanamycin and PCR analysis, 33 T0 plantlets were identified as transgenic. Seeds from twenty T0 plants were collected and planted as T1 lines. Two T1 lines were selected for further characterization. PCR and GUS staining analysis showed that TA3-13 was integrated into the T1 tobacco genome and expressed. When inoculated on leaves, the transgenic tobacco showed significant resistance against TMV and rot pathogen Pectobactrium carotovorum subsp. carotovorum. These results suggest that the expression of TA3-13 in tobacco can induce defense responses to pathogen infection.