The Strategies to Increase Taxol Production by Using Taxus Mairei Cells Transformed with TS and DBAT genes - the study of gene expression and transformation

Taxol is an expensive anti-cancer drug to cure ovarian, breast and lung cancers. How to increase the taxol yield in Taxus cell cultures has been viewed to be a great economical potential. Since taxol yield is low in plants and cell cultures, the greater amounts of two taxoids: 10-deactyl baccatin III (DB) and bacctin III (BC) were then used to be precursors that were synthesized to form taxol. To increase the taxoid yield in cell cultures, a good cell line and methyl jasnomate (MJ) treatment were proven to be effective in many studies. In our study, MJ is not only to increase taxoid yield, but also increase the kinds of taxoids. We presumed that MJ might be a good indicator to select important genes among the tens genes in taxol biosynthesis. We selected and cloned genes of taxadiene synthase (TS) and 10-deacetyl baccatin III-10-O-acetyl transferase (DBAT). TS is the first gene of taxol biosynthesis pathway, while DBAT gene controls the reaction of DB to become BC. We found the overexpression of these two genes in both needles and stems of Taxus mairei plants 8 hours after MJ treatment, indicating that transforming these two genes in cell cultures might increase taxoid yield. The construction of 35S promoter and sense DBAT, sense TS, and antisens DBAT gene were made and successfully transformed them into cell cultures. We expect that transformed cells would produce taxoids all the time without MJ treatment. Although the transgenic cells with sense DBAT gene did increase the yields of both BC and taxol, it was required MJ treatment to enhance more taxoid yields. It suggests that MJ might regulate genes more than we thought.