犬瘟热病毒小熊猫株核蛋白和融合蛋白基因克隆及序列分析

根据GenBank中报道的CDV核苷酸序列,设计合成了2对特异性引物,对犬瘟热病毒小熊猫株(CDVLP)核蛋白(N)和融合蛋白(F)两种主要结构蛋白基因进行了克隆、测序及序列分析。结果表明,CDVLP株N蛋白基因全长1571bp,预测编码523个氨基酸;F蛋白基因全长1989bp,预测编码662个氨基酸,F蛋白氨基酸序列中含有5个潜在的N-联糖基化位点。聚类分析提示,CDVLP株是一株与CDV强毒株亲源关系很近的毒株。用DNAstar软件对CDVLP株和Onderstepoort弱毒株N蛋白和F蛋白进行了疏水性及抗原表位预测分析。抗原表位差异提示CDVLP毒株N和F蛋白的免疫原性可能要优于Onderstepoort弱毒株。在分子水平上阐明了CDVLP株的N和F蛋白基因更适合作为构建基因疫苗和重组活载体疫苗的目的基因。

Gene clone and sequence analysis about nucleocapsid protein and fusion protein of CDV LP strain

According to the genome sequence of CDV reported in GenBank,two pairs of specific primers were designed and synthesized.Both N protein gene and F protein gene of CDV LP strain were respectively amplified by RT-PCR,cloned,sequenced.The results showed that the full length of N protein gene of CDV LP strain was 1 571 bp,which encoded 523 amino acids.The full length of F protein gene of CDV LP strain was 1 989 bp,which encoded 662 amino acids.There were five potential N-glycosylation sites in deduced amino acids sequence of F protein.The analysis of hydrophobicity,antigenic epitopes and surface probability plot of N and F proteins with DNAStar Program indicated that there were distinct differences between CDV LP strain and Onderstepoort vaccine strain.Contrast to Onderstepoort vaccine strain,there were higher antigen surface indices in N and F proteins of CDV LP strain.N and F protein gene of CDV LP strain were elucidated as aim gene of constructing gene vaccine as well as the recombinant vaccine on molecular level.