发根农杆菌(Agrobacterium rhizogenes) Ri T-DNA遗传转化丝石竹(Gypsophila paniculata)的研究

近年来,已发展出遗传转化高等植物的一些新技术,其中有些技术如脂质体融合,微注射技术和电击导入都是基于动物细胞培养方面的工作,而另一些技术是来自于植物界独特的天然转化系统,其中包括已知能遗传转化高等植物的农杆菌(Agrobacterium)的二个种,即致瘤农杆菌(A.tumefaciens)和发根农杆菌(A.rhizogenes),这二个种都能够将其致病质粒Ti或Ri所携带的DNA序列(T-DNA)插入到双子叶植物细胞核基因组中。pTi诱发寄主产生根基肿瘤,pRi诱发寄主产生毛状根。二者的差别可能是毛状根可以从毛状根培养物获得具有完整的T-DNA序列的有生育能力的再生植株,而从致病农杆菌(A.tumefaciens)菌株所诱发的肿瘤很难获得再生植株。因此,利用发根农杆菌(A.rhizogenes)pRi作为遗传转化高等植物的基因克隆载体的研究和应用日益受到重视。

A STUDY ON GENETIC TRANSFORMATION OF Rl T-DNA OF AGROBACTERIUM RHIZOGENES TO GYPSOPHILA PANICULATA

Young stems, leaves and callus of Gypsphila paniculata were inoculated separately with Agrobacterium rhizogenes strain LBA 9402. After 18 days from inoculation hairy roots were induced on the sites inoculated, which had not geotropism, grew luxurianlly and produceed branches on MS medium without any hormone. Calli were induced by exposing hairy root fragmants to MS medium supplemented with 2, 4-D 2mg/L and BAP 0. 5mg/L, which were subcultured for 7-8 weeks on MS medium containing 2,4-D 0.2mg/L, zeatin 2mg/L, and then transfered to hormone free MS medium for a regenerated plant. Agropine and mannopine were found out in the hairy roots, calli derived from hairy roots and the regenerated plants by means of electrophoresis examination, indicating that Ri T-DNA of Agrobacterium rhizogenes was conformed into nuclear gene group of G, paniculata.