灰飞虱携带的水稻条纹病毒NS2和NS3基因的分子变异  

Molecular Variality of NS2 and NS3 Genes from Rice Stripe Virus in Laodelphax striatellus

作　　者：任春梅[1] 程兆榜[1] 杨柳[1] 缪倩[1] 周益军[1] 

机构地区：[1]江苏省农业科学院植物保护研究所,江苏南京210014

出　　处：《西南农业学报》2016年第8期1854-1863,共10页Southwest China Journal of Agricultural Sciences

基　　金：国家自然科学基金(31201506);国家公益性(农业)行业专项(201003031);江苏省农业科技自主创新项目[CX(13)5026]

摘　　要：为揭示灰飞虱携带水稻条纹病毒（rice stripe virus，RSV）的NS2和NS3基因分子变异特征，采用单雌产卵法从江苏、云南、山东、河北等地获得20个灰飞虱携带的RSV分离物，RT-PCR扩增出NS2和NS3基因特异片段，并对扩增产物进行克隆测序，再结合Genbank中已报道的其他分离物序列，利用生物信息学软件分析不同寄主、地区分离物的分子变异特点及系统发育关系。序列测定表明，20个分离物NS2和NS32个基因核苷酸序列同源性分别为96．5％～100％（NS2）和95．4％～100％（NS3），推导编码的蛋白氨基酸序列同源性为97．0％-100％（NS2）和96．2％-100％（NS3）。基于核苷酸序列构建的系统进化树分析表明2个基因均可以明显分为2组，其中一组均为中国云南水稻上的分离物，2组间遗传距离分别为0．05711（NS2）和0．06081（NS3），2基因的Z—test的检测结果表明都处于强烈的负选择压下。从2基因氨基酸构建的系统发育树和变异热点上分析，其氨基酸序列的分子变异首先与地缘相关，2基因均可以分成中国云南及云南以外的2个地理亚群；其次与寄主相关，可以划分为灰飞虱和水稻2个寄主群。In order to reveal the molecular variation characteristics of NS2 and NS3 genes from rice stripe virus （RSV） in the small brown pl- anthoppcr （SBPH, Laodelphax strlatellua Fallen）, we collected twenty SBPH isofemale lines with RSV from Jiangsu, Yunnan, Shandong, Hebci province, China. The specific fragments of NS2 and NS3 genes were amplified by RT-PCR, then were cloned and sequenced. Bioin- formatics software was used to analyze the molecular variation characteristics and phyloganetic relationship of RSV isolates from different hosts and regions combining with other isolates sequences reported in Genbank. Sequence determination showed that the identities of NS2 and NS3 genes nucleotide and amino acid sequences among the 20 isolates ranged from 96.5 % to 100 % （ NS2 ） and 95.4 % to 100 % （ NS3 ）, 97.0 % to 100 % （ NS2 ） and 96.2 % to 100 % （NS3）. The analysis of phylogenetic tree constructed on nucleotide sequence showed that two genes were obviously divided into two groups, one group included all the rice isolates of Yunnan in China, genetic distance between the two groups were 0. 05711 （ NS2 ） and 0. 06081 （ NS3 ）, the results of Z-test showed that the two genes were under the pressure of strong neg- ative selection. Analysis of phylogenetic tree and variation hotspot constructed on NS2 and NS3 amino acid sequences, molecular variation of RSV was strongly associated with its geographical origin, two genes could be grouped into two geographical populations, i.e. Yunnan in Chi- na and the restswithout Yunnan in China; secondly associated with its host origin, two genes could be grouped into SBPH and rice populations.

关 键 词：水稻条纹病毒 NS2和NS3基因 分子变异 寄主群 地理亚群 

分 类 号：S432.45[农业科学—植物病理学]