侵染百合的黄瓜花叶病毒亚组Ⅱ分离物cp基因克隆和序列分析

Cloning and sequencing on cp gene of Cucumber mosaic virus subgroupⅡ isolated from Lily(Lilium cv.Oriental hybrids)

从云南大理的东方型百合上得到黄瓜花叶病毒分离物（CMV-DL）,ELISA检测初步确定为CMV亚组Ⅱ分离物,设计并合成CMV亚组Ⅱ的特异引物,RT-PCR扩增得到1条约800 nt的特异片段,经克隆及序列测定,该片段长828 nt,包含的外壳蛋白（CP）基因由657 nt组成。将该分离物的cp基因与其它14个CMV分离物进行同源性比较,在核苷酸水平上与CMV亚组Ⅰ和亚组Ⅱ的同源性分别为76.8%-78.1%和98.6%-99.2%;在氨基酸水平上与CMV亚组Ⅰ和亚组Ⅱ的同源性分别为82.0%-84.3%和95.9%-100.0%。结果表明CMV-DL为CMV亚组Ⅱ成员。

An isolate of Cucumber mosaic virus （CMV-DL） was obtained from Lilium cv. Oriental hybrids collected in Dali city, Yunnan province. The primary result showed that the isolate belonged to CMV subgroup Ⅱ from ELISA assay. A fragment of 828 nt was amplified by use of specific primers for CMV subgroup Ⅱ. The sequence of the fragment included 657 nt cp coding region. It was compared with previously reported sequences of 14 CMV isolates. The cp gene showed 76.8% -78.1% and 98.6% -99.2% identifies with that of subgroup I and subgroup Ⅱ at the nucleotide level, respectively. The sequence shared 82.0% -84.3% and 95.9% - 100.0% identities with that of subgroup Ⅰ and subgroup Ⅱ and at amino acid level respectively. The results showed that CMV-DL was one of the member in CMV subgroup Ⅱ.