Xia Zhi-Hui, Li Xiao-Bing, Chen Cai-Yan, Fan Hai-Kuo, Jiang Guang-Huai, Zhu Li-Huang, Zhai Wen-Xue
Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
Sheng Wu Gong Cheng Xue Bao. 2006 Mar;22(2):204-10.
The dominant gene Xa21 with broad-spectrum and high resistance to Xanthomonas oryzae pv. oryzae (Xoo) was transferred into C418, an important restorer line of japonica hybrid rice in China using double right-border (DRB) T-DNA binary vector through Agrobacterium-mediated transformation. 17 transgenic lines were Xa21-positive with high resistance to the race P6 of Xoo through PCR analysis and resistance identification, among the total 27 independent primary transformants (T0) obtained. The subsequent analysis of the T1 progenies of these 17 T0 lines through PCR-assisted selection and resistance investigation showed that four Xa21 transgenic T0 lines could produce selectable marker-free (SMF) progenies. The frequency of primary transformants producing SMF progenies was 15%. In addition, PCR analysis also revealed these SMF progenies did not contain vector backbone sequence, and they were named as SMF and vector backbone sequence-free (SMF-VBSF) Xa21 transgenic plants. The further molecular and phenotypic analysis of the T2 and T3 progenies testified the homozygous SMF-VBSF Xa21 transgenic plants were obtained with high resistance to Xoo.
利用双右边界（DRB）T-DNA双元载体，通过农杆菌介导的转化方法，将对水稻白叶枯病菌（Xanthomonas oryzae pv. oryzae，Xoo）具有广谱高抗性的显性基因Xa21导入中国粳型杂交水稻重要恢复系C418中。在获得的27个独立的初级转化体（T0）中，通过PCR分析和抗性鉴定，有17个转基因株系对Xoo小种P6具有高抗性且Xa21呈阳性。对这17个T0株系的T1代进行后续的PCR辅助选择和抗性调查分析表明, 4个Xa21转基因T0株系能够产生无选择标记（SMF）的后代。产生SMF后代的初级转化体频率为15%。此外，PCR分析还表明这些SMF后代不含有载体骨架序列，它们被命名为无选择标记且无载体骨架序列（SMF-VBSF）的Xa21转基因植株。对T2和T3代进行的进一步分子和表型分析证实获得了对白叶枯病菌具有高抗性的纯合SMF-VBSF Xa21转基因植株。
