流行性腮腺炎病毒疫苗株WM84六代次基因序列分析

目的分析6个代次流行性腮腺炎病毒疫苗株WM84融合蛋白(F)、血凝素神经氨酸酶蛋白(HN)和疏水蛋白(SH)的基因序列,并与Jery-Lynn(JL)株和ME株进行比较。方法WM84株病毒在原代鸡胚成纤维细胞(CEF)上连续传代至12代,观察各代病毒的培养特性,测定2、7、9、10、11、12代主要结构蛋白基因及高变区SH基因序列,与GenBank中参考毒株JL2、JL5和ME株进行比对,分析其核苷酸序列及相应氨基酸序列的差异,并构建系统进化树。结果WM84株病毒在CEF上连续传代至12代,其培养特性及病毒滴度基本稳定。与WM84株2代相比,其各代在主要蛋白基因区域有散在的核苷酸变化。7～12代病毒HN、F和SH基因与2代相比,核苷酸同源性分别为97.0%～100%、97.0%～100%及94.0%～100%;氨基酸同源性分别为98.3%～100%、97.2%～100%及94.1%～100%。2～7代病毒,HN、F和SH基因氨基酸与JL2株同源性为98.8%～99.5%,与JL5株同源性为94.1%～98.3%,传至11、12代,与JL5株同源性达99.8%～100%。结论WM84株2～7代病毒蛋白基因与JL2株十分相似,但在后续传代过程中出现了JL2株向JL5株转化的倾向。WM84株病毒在传代过程中HN及F基因结构基本稳定。

Sequencing of Mumps Vaccine Strain WM84 of 6 Passages

Objective To analyze the gene sequences of fusion (F) protein, hemagglutinin neuraminidase (HN) protein and hydrophobin SH of mumps vaccine strain WM84 of 6 passages and compare with those of Jery-Lynn(JL) and ME strains. Methods Subculture WM84 strain in primary chick embryo fibroblast (CEF) for 12 passages and observe the cultural characteristics of each passage. Sequence the main structural protein gene and the SH gene in highly variable region of passages 2, 7, 9, 10, 11 and 12 and compare with those of reference strains JL2, JL5 and ME in GenBank. Analyze the difference in nucleotides and the corresponding amino acids of WM84 strain and the reference strains to plot a phylogenetic tree. Results After subculture in CEF for 12 passages, the cultural characteristics and virus titer of WM84 strain were basically stable. Compared with that of passage 2, interspersed nucleotide changes were observed in main protein gene regions of other passages. The homologies of nucleotides of HN, F and SH proteins of WM84 strain of passages 7～12 to those of passage 2 were 97. 0%～100%, 97. 0%～100% and 94. 0%～100%, and those of amino acids were 98. 3%～100%, 97. 2%～100% and 94. 1%～100% respectively. The homologies of HN, F and SH gene of WM84 strain of passages 2～7 were 98. 8%～99. 5% to those of JL2 strain, and 94. 1%～98. 3% to those of JL5 strain. However, the homologies of WM84 strain of passages 11 and 12 to those of JL5 were 99. 8%～100%. Conclusion The virus protein genes of WM84 strain of passages 2～7 were highly homologous to those of JL2 strain. However, the homology to JL2 strain decreased, and that to JL5 strain increased, with the increasing passages. The HN and F gene structures of WM84 strain were basically stable during subculture.