芜菁花叶病毒不同分离物3'-cDNA片段的克隆及序列分析

 从河北、北京、山东泰安和潍坊等地区的萝卜、大白菜、甘蓝、油菜上得到8个芜菁花叶病毒(Turnip mosaic virus,TuMV)分离物,测定了它们3'-末端cDNA片段的序列。根据衣壳蛋白基因(cp)核苷酸序列可以将这8个分离物与另外2个TuMV分离物分为3组:泰安旧镇大白菜(JZBC)、甘蓝(JZGL)和萝卜(JZLB)分离物为一组;北京(BJILB)、潍坊萝卜分离物(WFLB)与引起萝卜红心病的TuMV分离物(WFLB99)为一组;泰安范镇、河北、潍坊(WFLB04)萝卜和泰安旧镇油菜(JZYC)上的TuMV分离物为一组。农壳蛋白氨基酸序列比较结果与此基本一致,所不同的是分离物WFLB99与所有分离物的差异均较大,形成单独一个分支。有必要对TuMV的变异情况和致病机理进行深入研究。

Cloning and sequencing of 3'-terminal genome of Turnip mosaic virus isolates

8 Turnip mosaic virus (TuMV) isolates were collected from radish, Chinese cabbage, cabbage and rape in Hebei Province, Beijing, Tai'an and Weifang of Shandong Province. Their 3'-terminal genomic sequences were cloned and determined in the study. The analysis results of nucleotide sequences of their coat protein genes with those of other 2 TuMV isolates showed that they could be clustered into three groups. Three isolates, Chinese cabbage (JZBC), cabbage (JZGL) and radish (JZLB) from the same field in Jiuzhen, a town in the suburb of Tai'an, belonged to one group. One isolate from radish in Beijing (BJLB) and two isolates from radish in Weifang (WFLB and WFLB99) formed the second group. WFLB99 was an isolate obtained in 1999 and caused reddening to browning of the radish flesh. The isolates from radish in Fanzhen (another town in the suburb of Tai'an) , Hebei, Weifang and an isolate from rape in Jiuzhen belonged to the third group. The comparison results of amino acid of coat protein were similar except the isolate WFLB99 it showed lower identities with the other isolates and formed a separate branch. Further studies on molecular variability of TuMV and their mechanisms of pathogenesis were under investigation.