戊型肝炎病毒摩洛哥株非编码区基因序列鉴定及基因型分型  

Determination and genotyping of the terminal untranslated region sequences of the hepatitis E virus isolated from Morocco

作　　者：陈国兵[1] 孟继鸿[1] 

机构地区：[1]东南大学基础医学院病原生物学与免疫学系,南京210009

出　　处：《中华微生物学和免疫学杂志》2004年第10期828-833,共6页Chinese Journal of Microbiology and Immunology

基　　金：国家自然科学基金资助项目 ( 3 0 2 712 3 1);江苏省自然科学基金资助项目 (BK2 0 0 2 0 5 3 )

摘　　要：目的　检测戊型肝炎病毒 (HEV)摩洛哥株非编码区 (UTR)序列 ,探讨HEV非编码区序列能否作为其基因型分型的依据。方法　使用基于RNA连接酶的cDNA末端快速扩增法 (RLM RACE)扩增HEV摩洛哥株 5′和 3′端片段并测序。所得序列使用LASERGENE和PHYLIP软件包与其他 2 9株HEV序列比较。结果　只有基于甲基化帽子结构的RLM RACE扩增出了 5′端片段。HEV摩洛哥株 5′端UTR有 2 6个核苷酸 ,3′端polyA之前有 6 5个核苷酸。基于 3′端UTR序列的进化树与基于全基因序列的进化树不全相同。HEV 3′端至少需要 10 0个左右核苷酸长的序列才可进行HEV基因型分型。结论　HEV摩洛哥株 5′端有甲基化帽子结构。HEV 3′端UTR序列不能完全代替全基因组序列进行基因型分型。部分序列替代全基因组进行基因型分型时需要考虑其部位和长度因素。Objective To obtain the untranslated region (UTR) sequences of hepatitis E virus (HEV) isolated from Morocco, to find whether the UTR sequences can be used to distinguish HEV genotypes from that of HEV complete genome sequences. Methods A method of RNA ligase-mediated rapid amplification of cDNA ends (RLM-RACE) was employed to obtain the 5′- and 3′-terminal sequences of HEV Morocco strain. The sequences of the Morocco strain were compared with that of other 29 strains by the LASERGENE and PHYLIP softwares. ResultsThe 5′ PCR product was obtained only from the RLM-RACE based on the capped RNA template. The 5′ UTR of the Morocco strain has 26 nucleotides, and the 3′ UTR has 65 nucleotides upstream to the polyA. The phylogenetic tree based on the sequences of 3′ UTR is not the same as that based on the complete sequences. At least 100 base pairs in HEV 3′-terminal region are needed to construct the phylogenetic tree. Conclusion The genome of HEV Morocco strain was a methylated cap structure. The 3′ UTR sequence cannot be used for HEV genotyping for all HEV strains in place of the whole HEV genome sequence. The influence of location and length must be considered when using partial sequences to substitute the complete sequences in genotyping.

关 键 词：HEV 分型 戊型肝炎病毒 基因型 非编码区 基因序列 核苷酸 RACE CDNA末端快速扩增 进化树 

分 类 号：R373[医药卫生—病原生物学]