Enhancing lignan biosynthesis by over-expressing pinoresinol lariciresinol reductase in transgenic wheat.

摘要

Possibility of enhancing lignan biosynthesis in wheat by genetic transformation with the Forsythia intermedia pinoresinol lariciresinol reductase (PLR) gene was studied. Wheat cv. Madison, Fielder and Bobwhite were transformed under the regulatory control of the corn ubiquitin promoter. Of the 217 putative transformants, 24 lines tested positive for the bar gene based on the leaf painting assay and 3 transformants with the inserted ubiquitin-PLR cassette were obtained. Southern blotting further demonstrated 1 or multiple copies (<=5) of transferred PLR gene in these 3 transgenic plants and increased expression of PLR gene was noted in 2 of the 3 transformants according to real-time PCR. In addition, concn. of a major lignan, secoisolariciresinol diglucoside (SDG) was enhanced in one of the sub-lines to 117.9 +or- 4.5 mug/g compared with 52.9 +or- 19.8 mug/g in the Fielder wild type. It is suggested that with further improvements to expression stability and transformant efficiency, the enhanced SDG content could result in significant promotion of wheat products in cancer prevention.