犬瘟热病毒AH株全基因组序列测定及其分子特征

GENOME SEQUENCING AND ANALYSIS OF CANINE DISTEMPER VIRUS STRAIN AH

本研究对犬瘟热病毒(Canine distemper virus,CDV)安徽分离株(CDV-AH株)的全基因组序列进行了测定和分析。根据GenBank上已发表的部分CDV基因组全长序列设计了8对特异性引物,RT-PCR方法分段扩增出CDV-AH株的全基因组序列。采用DNAStar软件和MEGA软件对CDV-AH株与其他CDV毒株的基因序列进行了比对和分析,并绘制系统进化树。结果显示,CDV-AH株全长15 690 bp,编码6种结构蛋白(N、P、M、F、H和L),与CDV-PS株核苷酸序列同源性最高,为98.8%,而与CDV-1以及Onderstepoort等疫苗株的序列同源性较低,为92.1%。CDV-AH株在保守区域出现15处氨基酸突变,这些突变对其所编码蛋白结构和功能的影响需要进一步研究。基于H基因序列的系统进化分析表明,CDV-AH株与其他CDV野毒株共同形成一个拓扑群,属于亚洲Ⅰ型。

The complete genome of Canine distemper virus （CDV） strain AH isolated from Anhui province was subcoloned and sequenced in the present study. Total 8 pairs of specific primers were designed according to the CDV reference for amplification of the complete genome of CDV-AH strain in RT-PCR. Subsequently, the DNAStar software and MEGA software were used to compare and analyze the gene sequences of CDV-AH strain with reference strains. The results showed that total length of CDV-AH was 15 690 bp encoding 6 structural proteins （N P, M, F, H and L）. The CDV-AH strain had 98.8% nucleotide sequence homology with CDV-PS strain and 92.1% with CDV-1 and Onderstepoort vaccine strains. The analysis of amino acid sequences showed 15 amino acid mutations in the conserved region of CDV-AH and the effect of these mutations on the protein structure and function need to be further studied. In addition, phylogenetic analysis of the CDV-AH strain and reference strains was carried out based on the H gene sequence. The results showed that the CDV-AH strain and other CDV wild strains together came from a topological group belonging to the Asian I type.