Complete Sequence Analysis and Subgroup Identification of Cucumber mosaic virus from Nicotiana tabacum in Hubei

In order to identify the subgroup type of CMV(Cucumber mosaic virus) in Hubei tobacco,CMV HB24 strain was isolated,and the full-length cDNA sequence of genomic RNAs of the isolate was determined by RT-PCR and sequence analysis.The results showed that:HB24 RNA1(GenBank:KC019299) consisted of 3363 nucleotides(nt) and encoded 1a protein of 993 amino acid residues(aa),RNA2(GenBank:KC019300) consisted of 3049 nt and encoded 2a protein of 859 aa and 2b protein of 111 aa,RNA3(GenBank:KC019301) contained 2216 nt and encoded 3a protein of 279 aa and CP of 218 aa.The results of nucleotide sequence similarity indicated that:the similarities of HB24 RNAs with the RNAs of Fny,SD,Q strains were:RNA1:91.6%,91.1%,75.9%;RNA2:91.8%,97.8%,69.5%;RNA3:92.1%,93.4%,73.2%,respectively.The similarities of HB24 RNAs with the RNAs of PSV-ER(Peanut stunt virus) were RNA1:65.5%,RNA2:56.7%,RNA3:54.1%;and that with the RNAs of TAV-V(Tomato aspermy virus) were 66.9%,57.7%,51.5%,respectively.According to RNA3 5' NTR(Nontranslated region) structure analysis,and phylogenetic tree analyses of RNA3 5'NTR and CP gene nucleotide sequences,HB24 belonged in CMV IB subgroup.