【摘要】 从广西南宁田间表现曲叶症状的番木瓜植株上分离到病毒分离物G4,经三抗体夹心ELISA(TAS-ELISA)检测,G4与粉虱传双生病毒的抗体呈阳性反应。对G4 DNA-A全序列测定和分析表明,G4 DNA-A全长2 748个核苷酸,共编码6个ORFs。同源性比较及系统进化关系分析表明,G4 DNA-A与在亚洲发现的粉虱传双生病毒关系较近,其中与我国报道的中国番木瓜曲叶病毒(PaLCuCNV)同源性最高,达到98.0%。进一步比较发现,G4 DNA-A编码的AV1、AV2、AC1、AC2、AC3和AC4与PaLCuCNV相应ORFs的氨基酸同源性分别为98.4%、95.7%、97.5%、97.8%、94.1%和94.6%,表明G4应属于PaLCuCNV的一个分离物。G4编码的ORFs与中国胜红蓟黄脉病毒(AYVCNV)、辣椒曲叶病毒(PepLCV)及烟草曲茎病毒(TbCSV)有较高的氨基酸同源性,可能起源于共同的祖先。利用DNA-B及卫星DNAβ的保守引物均未能从G4分离物中扩增出相应的组分。更多还原

【Abstract】 V irus isolate G4 was collected from papaya plant showing leaf curl symptoms from Nanning,Guangxi province.G4 was able to react specifically with antibod ies raised against particles ofwhitefly-transm itted gem ini-viruses(WTGs) in TAS-ELISA.The complete sequence of G4 DNA-A was determ ined to be 2 748 nucleotides(nt).A lignment and phylogenetic analysis show thatG4 DNA-A clusters togetherwithWTGs originated from Asian continent and is most closely related toPapaya leaf curl China virus(PaLCuCNV),with 98.0% nt identity.Comparisons show thatG4 DNA-A encoded AV1,AV2,AC1,AC2,AC3 and AC4 share 98.4%,95.7%,97.5%,97.8%,94.1% and 94.6% am ino acid sequence identity,respectively,with those of PaLCuCNV,ind ica-ting thatG4 is an isolate of PaLCuCNV.The ind ividualORFs encoded by G4 DNA-A share high am ino acid se-quence identities with those ofAgeratum yellow vein China virus(AYVCNV),Pepper leaf curl virus(PepLCV) andTobacco curly shoot virus(TbCSV),suggesting that the ORFs of these virusesmay be derived from the com-mon ancestor.Attempts to amplify the putative DNA-B or satellite DNAβwith conserved primer pairs by PCR have been unsuccessful.更多还原