UPTAKE OF EXOGENOUS DNA BRASSICA-NAPUS DRY SEED EMBRYOS VIA CELLULAR PERMEABILIZATION AND TRANSIENT EXPRESSION OF NPTII ACTIVITY

A simple method of exogenous DNA uptake by dry seed embryos has been e xamined which is evaluated by transient gene expression. The uptake an d expression of foreign DNA was tested employing a plasmid containing nptll gene and assaying, later, the enzyme activity. To facilitate the uptake of foreign DNA by dry seed embryos of Brassica napus ISN706, v arious permeabilizing agents, like dimethylsulphoxide, toluene, Triton X-100 and saponin, were tested for their effectiveness in transiently permeabilizing the plasma membranes in the concerned tissues. The tre atment of dry seed embryos with 1.0 mg/ml saponin fdr 45 min was found to be the most effective for uptake of plasmid DNA without adversely affecting embryo viability. The method was tested also with several ot her cultivars and also species, namely B. napus ISN 129, B. napus ISN 106, B. napus ISN 128, B. napus ISN 706, B. napus B054, B. carinata, B . juncea, and B. oleracea. Transient gene expression was seen in all c ases, indicating that the method may be relatively free of genotypic c onstraints for its wider application.