GENETIC-TRANSFORMATION OF MATURE TAXUS - AN APPROACH TO GENETICALLY CONTROL THE IN-VITRO PRODUCTION OF THE ANTICANCER DRUG, TAXOL

This report demonstrates genetic transformation of two Taxus species, Taxus brevifolia and Taxus baccata, and expression of bacterial genes transferred into the plant genome by Agrobacterium tumefaciens. We use d two strains of Agrobacterium tumefaciens (Bo542 and C58) to inoculat e shoot segments of mature yew trees. The highest gall formation frequ ency (28.3%) was achieved with Taxus baccata using the Bo542 strain. A grobacterium tumefaciens strain Bo542 induced significantly more galls (24%) than strain C58 (4%). Although we were able to induce tumors on both Taxus species, Taxus baccata showed significantly higher suscept ibility (14%) than Taxus brevifolia (7%). In contrast to untransformed callus cultures, the gall cell lines proliferated on phytohormone-fre e medium and produced agropine as the result of T-DNA transfer. Southe rn blot analysis showed the presence of T-DNA sequences in the genome of these cell lines. Taxol and related taxane produced by the transgen ic callus cultures were identified by mass spectrometry and immunoassa y with monoclonal antibodies specific for taxol.