F基因型腮腺炎病毒全基因组基因特征分析

Genetic Analysis of a Genotype F Mumps Virus Based on Its Complete Genome Sequence

为了解我国现流行的F基因型腮腺炎病毒全基因组的基因特征，本研究选择对腮腺炎病毒F基因型参考株Muvi／shand。ng．CHN／4．05IF]进行全基因组测序，结合其它来自于GenBank的腮腺炎病毒全基因组序列，共同分析我国流行的F基因型腮腺炎病毒的全基因组特征及其与现有疫苗株的遗传差异及抗原位点变异情况。通过研究发现，和腮腺炎病毒其它基因型相比，腮腺炎毒株MuVi／shandong．CHN／4．05Er]全基因组核苷酸差异在3．8％～6．5％之间，其中与A基因型（疫苗株）差异最大，与B和N基因型差异最小。腮腺炎毒株MuVi／Shan—dong．CHN／4．os[F]和疫苗株在全基因组序列上分别存在26个和25个N糖基化位点，和疫苗株相比，腮腺炎毒株MuVi／Shandong．CHN／4．05[x]在HN蛋白上第464~466氨基酸位点上增加了一个N一糖基化位点，而其它基因型的腮腺炎病毒在这个位点上也均为N_糖基化位点。另外，腮腺炎毒株MuVi／Shandong．CHN／4．os[E]和疫苗株在其它已知的抗原相关位点上也存在着氨基酸变异。我国现流行的腮腺炎流行株与腮腺炎病毒其它基因型及疫苗株之间在全基因组上已存在较大的差异，提示需进一步加强对国内现有腮腺炎流行株与疫苗株之间的遗传变异分析，系统评价当前疫苗的免疫保护效果。

Mumps virus strains of genotype F have been circulating in China for decades. To identify genetic variation of mumps virus based on the complete genome sequence of a mumps isolate of genotype F, the complete genome of the genotype F reference strain, MuVi/Shandong. CHN/4.05 [F] was sequenced. Ge- netic characteristics of this virus were analyzed and compared with the complete genome sequences of oth- ers genotypes available in GenBank. The genetic differences in antigenic sites were also compared between the genotype F strain and the vaccine strains. The nucleotide differences between MuVi/Shandong. CHN/ 4.05 [F] and other genotypes of mumps virus based on the whole genome ranged between 3.8% and 6.5%. The maximum and minimum difference was found between MuVi/Shandong. CHN/4.05 [F] and genotype A （the vaccine strains）, and genotype B-N strains, respectively. There were 26 N-glycosylation sites in the strain MuVi/Shandong. CHN/4.05 [F] and all other genotypes of mumps virus, however, one N-glycosylation site was absent from the vaccine strains, which was at the aa position 464-466 of the HN gene. Variation was detected at some of the known antigenic sites of mumps virus strain MuVi/Shan- dong. CHN/4. 05 [F] and the vaccine strains. Genetic variations were detected in the epidemic mumps vi- rus strain in China as well as in other genotypes of mumps virus strains and the vaccine strains across the complete genome. These results indicate the need to further strengthen the surveillance of genetic variation of wild type mumps virus.