| 摘要: |
| 为了研究IBV陕西分离株M基因的遗传变异情况及分子特征，参照NCBI所登录的IBV M基因序列设计了1对引物，应用RT-PCR方法对陕西8株IBV分离株的M基因进行扩增，并构建克隆载体，对阳性质粒测序后进行核苷酸序列及氨基酸序列同源性和进化发生关系分析，并对M蛋白的二级结构和跨膜区进行预测。结果表明，8个IBV分离株间的M基因核苷酸和M蛋白氨基酸同源性分别为92.3％～99.8％和95.4％～100％，分离毒株与参考毒株的M基因核苷酸和M蛋白氨基酸序列同源性分别为87.4％～99.5％和89.4％～99.5％；分离毒株与参考毒株M蛋白的α-螺旋结构主要分布在N端前100氨基酸肽段区，其他的部分主要是哥折叠和无规则卷曲结构；分离毒株的M蛋白均包含有3个跨膜区。表明IBV分离株M蛋白在基因序列和二级结构上相对保守。 |
| 关键词: IBV M蛋白基因 遗传变异 分离株 |
| DOI： |
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| 基金项目:陕西省科技攻关项目（2005K01-G20-02） |
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| Cloning and molecular hereditary variation analysis of Mgenes of IBV isolates from Shaanxi Province |
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| Abstract: |
| To study the genetic variation of the IBV M protein,a pair of primers were designed according to the nucleotide sequence stowed by NCBI,then the M gene of the 8 nephropathogenic isolates were amplified,and the clonal plamic was constructed,and then the positive plasmids were sequenced after identification by PCR and restriction endonuclease.The sequence distance of nucleotide and predicted amino acid,phylogenetic tree,the predicted secondary structure and the membrane-spanning regions of M protein were analyzed through DNAStar,AnthePro5.0 and PRED-TMR biological softstares.The results showed that the 8 isolates had BamHI cleavage sit,except YX and WH isolates.And they shared 87.4％－99.5％and 89.4％－99.5％ identity with the control strains in sequence of nucleotide and predicted amino acid,respectively;and 92.3％－99.8％ and 95.4％－100％ identity among the eight IBV isolates.The α-helix regions mainly located in the first 100aa of the isolates M proteins,and the rests were comprised of β-sheets and coils regions.The M protein of all isolates had a triple-spanning region in the α-helix regions of the N end.All in all,the gene of AIBV M protein was raather conservative. |
| Key words: IBV Matrix glycoprotein genetic genetic variation isolates |
