通过RT-PCR扩增了黄瓜绿斑驳花叶病毒(Cucumber green mottle mosaic virus,CGMMV)济南分离物(CGMMV-JN)的基因组片段。序列测定结果表明CGMMV-JN基因组全长6 424核苷酸(nt),5'-和3'-UTR分别为60和176 nt,含有4个ORF,分别编码129 kDa和186 kDa复制酶相关蛋白、29 kDa移动蛋白及17.4 kDa外壳蛋白。CGMMV-JN与另外29个CGMMV分离物全基因组核苷酸序列一致率为90.0%-99.7%。重组分析发现韩国KOM(AF417243)、以色列EC(KF155231)、印度(DQ767631)和我国河北的CHB(KJ658958)4个分离物在RdRp编码区存在重组。系统发育分析结果表明,这些分离物可分成3个组。选择压力分析结果表明cp基因处于正选择,其它基因处于负选择。本文研究的结果为黄瓜绿斑驳花叶病毒的监测及防控提供了理论依据。
The complete genome of a Cucumber green mottle mosaic virus isolate collected from watermelon in Ji'nan(CGMMV-JN) was amplified by RT-PCR.Sequencing analysis revealed that the full-length genome of CGMMV-JN is 6 424 nucleotides(nt) in length,of which the 5'-untranslated region(UTR) and 3'-UTR were60 and 176 nt,respectively.The complete genome of CGMMV-JN contained four open reading frames(ORFs),which encode 129 kDa and 186 kDa RNA-dependent RNA polymerase(RdRp),29 kDa movement protein,17.4kDa coat protein(CP),respectively.CGMMV-JN shared nucleotide identities of 90.0%-99.7%with other CGMMV isolates at the complete genome levels.Recombination analysis indicated that four isolates from Korea,Israel,India and China,respectively,presented recombination in ORF encoding RdRp.Phylogenetic tree analysis with complete genomic sequences demonstrated that the CGMMV isolates were clustered into three groups correlated with their geographical origin.Selection pressure analysis suggested that only CP ORF was under positive selection.Our study provided theoretical basis for the monitor and control of CGMMV.