西尼罗病毒Chin-01株基因组编码区序列测定及论著分析

Determination and analysis of coding sequences of West Nile virus Chin-01 strain

目的 :对保存的西尼罗病毒Chin_0 1株基因组编码区序列进行测定 ,了解其与已报道毒株的序列差异及系统进化关系。方法 :对Chin_0 1株病毒基因组编码区分区段进行RT_PCR扩增 ,分别将扩增产物直接进行测序 ,采用DNAstar软件将测序片段拼接获得全长编码区序列。结果与结论 :Chin_0 1株基因组编码区全长 10 30 2nt ,为单一读码框架 ,编码 3434个氨基酸。其中结构蛋白基因为 2 373nt,依次编码 4种结构蛋白 (C ,PrM ,M和E) ;非结构蛋白基因全长 792 6nt,依次编码 7种非结构蛋白 (NS1,NS2a ,NS2b ,NS3,NS4a ,NS4b和NS5 )。序列同源性分析表明 ,Chin_0 1株与埃及Eg10 1株高度同源 ,两者氨基酸序列仅有 0 .3%的差异。该株西尼罗病毒基因组编码区序列已输入GenBank数据库。

Objective:To study the interrelation and variation between West Nile virus(WNV) Chin-01 stain and other WNV strains by sequencing and analyzing the coding sequence of WNV Chin-01 strain.Methods:The coding sequences were amplified by reverse transcription polymerase chain reaction(RT-PCR), and the cDNA fragments were sequenced and then analyzed with DNAstar. Results and Conclusion:Chin-01 strain has the common genome structure of West Nile virus. Sequence of coding region beginning at nucleotide 97 contains a single long open reading frame (ORF), which contains 10?302 nucleotides. The ORF encodes a precursor polyprotein of 3?434 amino acids, which is cleaved into four structural proteins and seven nonstructural proteins, designed C-PrM-M-E and NS1-NS2a-NS2b-NS3-NS4a-NS4b-NS5 in order. Compared with Eg101 strain, Chin-01 strain shows a nucleotide sequence identity of 97.3% and an amino acid sequence identity of 99.7%. Homology analysis among 9 strains of West Nile viruses revealed that Chin-01 belongs to West Nile virus lineage 1, and is most closely related to Eg101 strain.