小西葫芦黄花叶病毒辽宁分离物的鉴定与序列分析

从辽宁省沈阳市和盖州市分别采集表现花叶的南瓜样品,经透射电镜负染色实验,观察到典型的马铃薯Y病毒属(Potyvirus)线状病毒粒子.利用Potyvirus通用引物Legpoty F/LegpotyR分别对3个沈阳样品和3个盖州样品进行RT-PCR扩增,得到预期片段,克隆并测序.Blast显示6个病毒样本与小西葫芦黄花叶病毒(ZYMV)同源性最高,均大于99%.利用已经报道的特异引物ZYMV-F/ZYMV-R,从6个样本中扩增到约1.2 kb的ZYMV片段,片段包含完整的外壳蛋白(CP)基因.基于CP的核苷酸序列同源性分析,发现2个ZYMV辽宁分离物与山西分离物ZYMV-[CN:SX:Chrysanthemum:14](KP742962)同源性最高,达99.1%和99.4%.系统进化树分析表明,2个ZYMV辽宁分离物与山西分离物ZYMV-[CN:SX:Chrysanthemum:14]聚集在一个分支,推测ZYMV辽宁分离物与山西分离物亲缘关系最近.

Identification and sequence analysis of Zucchini yellow mosaic virus in Liaoning

Cucurbita moschata samples showing yellow mosaic symptoms were collected from Shenyang and Gaizhou, Liaoning Prov-ince, and virions with a typical morphology of Potyvirus were observed by transmission electron microscope ( TEM) . The universal degenerate primers LegpotyF/LegpotyR was used for Potyviruses detection for 3 symptomatic leaf samples from Shenyang and Gaizhou by RT-PCR. Subsequently, the expected fragments were amplified, cloned and sequenced. Blast results showed that all 6 samples shared the highest identities with Zucchini yellow mosaic virus (ZYMV) (all above 99%). Based on specific primers ZYMV-F/ZYMV-R, 1.2 kb ZYMV fragment containing complete coat protein (CP) gene was obtained. Referring to the nucleotide sequence of CP, homology analysis results confirmed that two Liaoning isolates of ZYMV had the highest homology with Shanxi isolate ZYMV-[ CN:SX:Chrysanthemum:14] ( KP742962) , with identity being 99.1% and 99.4%. The phylogenetic tree results showed that they were also clustered with ZYMV-[ CN:SX:Chrysanthemum:14] in the same branch. Liaoning isolates of ZYMV was considered being most related to Shanxi isolates.