Abstract:

Mechanical injury or pathogen and insect invasion usually involves a seties of defence-related gene expression in plants, Some of these genes show distinct wound-inducibility.One of the wound-inducible win3 multigene families from hybrid poplar, encoding a protein similar to sweet potato sporamins and legume trypsin inhibitors, was previously isolated by Bradshaw et al.(1989).To further understand the role of its upstream regulatory region in wound-mediated response, and its possibility to be used in geNetic engineering for the control of the expression of foreign genes, the win3 gene promoter WINP(705bp)and WIDP(791bp)were amplified from P.nigra and P.deltoides, respectively.Both promoters were fused to the E.coli β-glucuronidase(GUS)reporter gene, and introduced into tobacco plants by virtue of Agrobacte rium-Ti system.This study demonstrated that GUS expression responded to wounding locally and remotely in transgenic tobacco under the WIN(D)P control, and the biochemical and histochemical assays of GUS activity for 8 transgenic lines gave the similar expression pattern as reported by Hollick et al. (1995).It was also observed that the responsibility to wounding of WINP was always stronger than that of WIDP, both on the injured or uninjured sites.Further modification of both promoters is necessary to increase their ability to enhance the expression thus to be used in genetic engineering to obtain wound-inducible expression of foreign gene(s).

Key words: Wound-inducible promoter, GUS reporter gene, Transgenic plant