杭州地区玉米病毒病dsRNA序列分析

Sequence Analysis of dsRNA Segments from Infected Maize from Hangzhou China

从杭州地区采集花叶症状的玉米,抽提双链RNA(double-stranded RNA,dsRNA),用单引物扩增方法(Single primer amplification technique,SPAT)对dsRNA进行RT-PCR扩增,获得了三条dsRNA片段的cDNA克隆并测定全序列。核苷酸水平上,三条片段(长度分别为1801bp、2193bp和3164bp)分别与水稻黑条矮缩病毒(Rice black-streaked dwarf virus,RBSDV)的第十(AF227205)、第七(AJ297428)和第五(AJ409147)号片段序列存在高达98%的同源性,与玉米粗缩病毒(Maize rough dwarffijivirus,MRDV)相应片段序列同源性最高为88%。在氨基酸水平上,推测的氨基酸序列也与RBSDV相似性较高,而与MRDV的相似性较低。序列同源性分析结果表明:三条片段来源于RBSDV。因此,该地区发生的玉米病毒病病原是水稻黑条矮缩病毒而不是玉米粗缩病毒。

Natural-infected maize with strip mosaic symptoms were collected from Hangzhou,China.Double stranded RNAs were amplified using SPAT（single primer amplification technique,SPAT） and viral genomic segments were cloned.Sequence analysis revealed that three segments（1801bp、2193bp and 3164bp,respectively ）shared 98% identity,at nucleotide level,with the tenth（AF227205）,the seventh（AJ297428） and the fifth（AJ409147） segments of rice black-streaked dwarf virus（RBSDV）,and their similarity were less than 88% with Maize rough dwarf fijivirus（MRDV）.They showed higher homology with RBSDV than MRDV at amino acid level,too.Results for sequence homology analysis indicated that the three segments obtained from dsRNA sequencing originated from RBSDV,which is regarded as the main virus infecting maize in this area.