title: New gene construction strategy in T-DNA vector to enhance expression level of sweet potato sporamin and insect resistance in transgenic Brassica oleracea.
abstract: Sporamin, an abundant storage protein in tuberous roots of sweet potato, possesses strong inhibitory activity against trypsin and pest-resistance. To promote consistent high-level expression of sporamin and insect resistance in transgenic Brassica plants, a wound-responsive sporamin promoter (Pspoa) alone or combined with matrix-attached-region-like DNA segment (spoMAR) were constructed for driving sporamin cDNA. The results showed the transgenic plants containing Pspoa-drived sporamin and spoMAR displayed the highest level and low inter-transformant variability of sporamin expression, and the ability of insect resistance of transformants positively correlated with sporamin activity. Furthermore, expressions of Pspoa-drived sporamin especially combined with the spoaMAR retains high and steady levels in the T(1) and T(2) generations, in marked contrast to the variable expression patterns observed in CaMV35S promoter-driven transformants. This study evidently indicates that the Pspoa and spoaMAR would be very efficient for high transgene expression in plants and obtaining inherently stable transformants in consecutive progenies.
authors.affiliation: Graduate Institute of Plant Biology, College of Life Science, National Taiwan University, Taipei 106, Taiwan.
authors.forename: Huai-Ju
authors.initials: HJ
authors.lastname: Chen
authors.forename: Shu-Jen
authors.initials: SJ
authors.lastname: Wang
authors.forename: Chien-Cheng
authors.initials: CC
authors.lastname: Chen
authors.forename: Kai-Wun
authors.initials: KW
authors.lastname: Yeh