[The research on the expression of rabbit defensin (NP-1) gene in transgenic tomato].

Rabbit defensin NP-1 is one kind of alpha-defensins. It is composed of 33 amino acids. It was firstly extracted from polymorphonnuclear neutrophile of rabbits. It displayed resistance to bacteria, fungi and virus, especially high resistance to bacteria. In our experiments NP-1 gene was constructed into a plant expression vector. Eight transgenic plants containing the rabbit defensin gene (NP-1) were obtained through agrobacterium-mediated transformation. The transgenic plants were analysized by PCR, Southern hybridization, Northern dot blot hybridization and in vitro microbicidical activity against E. coli and Fusarium oxysporum. The results showed that NP-1 gene was transformed into the tomato, and the transgene displayed physiological-level expression. The transgenic tomato also showed resistance to pathogen Fusarium oxysporum in vivo. Our experiments paved a way for pathogen resistance breeding of tomato.