汉坦病毒K24株M和S片段基因的结构特征

Structure Characterstics of M&S Segment of Hantavirus,K24,strain

为研究汉坦病毒K2 4株M和S片段基因的结构特征 ,从病毒感染细胞提取细胞总RNA ,经 35个循环的一次性PCR得到了与理论值相符合产物 ,将RT -PCR产物直接克隆T载体 ,经K2 4毒株M片段的全基因序列共 36 5 3个核苷酸 ,四种核苷酸的酶切和PCR鉴定正确的克隆通过柱纯化后进行序列测定 ,结果比例分别为A 30 .4 4 % ,T30 .14 % ,G 2 0 .72 % ,C 18.70 % ,GC含量为 39.4 2 % ,AT含量为 6 0 .5 8% ,编码 1133个氨基酸。S片段的全基因序列共 1772个核苷酸 ,四种核苷酸的比例分别为A31.30 % ,G2 6 .0 5 % ,T2 2 .79% ,C19.77% ,GC含量为 4 5 .81% ,AT含量为 5 4 .19% ,共编码 4 2 9个氨基酸。K2 4株M片段核苷酸全基因和氨基酸与HTN型毒株同源率分别为 70 .7%～71.2 %和 75 .9%～ 76 .9% ,与SEO型为 95 .2 %～ 99.2 %和 95 .9%～ 99.4 %。S片段与HTN 76～ 118和SEOSR 11病毒的比较 ,核苷酸同源率分别为 74 .0 %和 95 .6 % ,氨基酸同源率为 83.3%和 97.9% ,与M片段的结果相类似。M片段氨基酸与SEO型 10个毒株存在 4个氨基酸替代。

Our previous study showed that K24 strain was an antigenicity broad Hantavirus SEO type strain.In this paper we studied the molecular characteristics of K24 strain.The total cellular RNA was extracted from infected cell culture and the M and S segment gene were amplicated by RT PCR and then cloned and sequenced.The results indicated that the K24 strain complete M genome segment was 3 652 nucleotide in length encoding 1 133amino acid,and the complete S genome segment was 1 772 nucleotide encoding 429 amino acid.Comparing with other hantavirus strains,the homology of M genome segment with that of HTN virus is 70.7%～ 71.2% in nucleotide level and 75.9%～76.9% in amino acid level respectively,while with that of SEO virus strains it was 95.2%～99.2% at nucleotide level and 95.9～99.4% at amino acid level.The homology of S genome segment with HTN 76 118 and SEO SR 11 showed 74.0% and 95.6% at nucleotide level,and 83.3% and 97.9% at amino acid level.The results are similar to that of M genome segment.When compared with 10 SEO virus strains,there were 4 amino acid differencesin the M genome segment,whcih might be responsible for the antigenicity characteristics broad.Phylogenic trees were constructed depending on the sequences of nucleotide and amino acids respectively.