伪狂犬病病毒Ea株Us9基因的克隆与序列分析

Cloning and Sequence Analysis of the Us9 Gene of Pseudorabies Virus Ea Strain

对含伪狂犬病病毒Ea株BamHI7片段的质粒pUC6.6进行亚克隆 ,构建了仅含Us9基因约 0 .6kb片段的重组质粒pSKMN0 .6。双脱氧末端终止法进行双链测序 ,结果表明 :Us9存在 2种可能的同C_末端的编码形式 ,分别编码 10 6或 98个氨基酸残基 ,Us9基因与其下游的Us2 (2 8K)基因之间存在约 2 0 0bp的非转录区。将Ea株Us9基因序列同国外Rice株进行同源比较 ,Ea株Us9基因存在多处点突变 ,但总的同源性达 96%。将推导的氨基酸序列与人单纯疱疹病毒I型 (HSV_1)Us9进行比较 ,发现二者在组成和结构上存在多处保守序列 ,尤其是潜在的酪氨酸磷酸化位点 ,C_端疏水性氨基酸以及由连续 6个带正电荷的精氨酸残基组成的核定位信号序列 。

The Recombinant plasmid pSKMN0.6,containing the complete Us9 gene of pseudorabies virus Ea strain,was constructed by subcloning from the plasmid pUC6.6,containing of the BamHI fragment 7 of Ea Strain.The whole nucleotide sequence of the 0.6kb fragment was determined by dideoxygen termination method and the result showed that there were two kinds of open reading frame,which was in_frame in C_termination and could code 106 or 98 animo acids,respectively.When compared with that of PRV Rice strain,there were multipile site_mutations in the Us9 gene of PrV Ea strain,and the diversity of amino acid residues also existed.When compared with the animo acid of Us9 of herpes simplex virus I(HSV_I),there existed several conserved founctional domains,including potential tyrosine phosphorylation site,the carboxy_terminal hydrophobic domain that function as span membrances and the string of six orginines just preceding the span membranes.On the other hand,the differences of the potential N_glycosylation sites and the percent of the serines in the whole sequences were noticed.