我国部分地区呼吸道合胞病毒地方株磷蛋白基因序列分析

Sequence analysis of phosphoprotein genes of respiratory syncytial virus field strains isolated in China

目的 了解我国呼吸道合胞病毒 (RSV)地方株的P(Phosphoprotein ,P)蛋白基因状况和变异特征。方法 选取不同地区具有不同流行特征的 6株RSV地方株 ,以提取的病毒mRNA为模板进行逆转录 聚合酶链扩增 (RT PCR)扩增、目的基因的克隆及序列测定分析。结果 地方株和同亚型原型株之间P蛋白核苷酸序列及推导出的氨基酸序列同源性均超过 95 % ;不同亚型间存在较大差异 ,核苷酸全序列同源性低于 85 % ,尤其在 3′端非编码区及中间变异区。由氨基酸序列推导出的疏水性分析图显示 ,A、B亚型中间变异区存在疏水性的不同 ,这为解释A、B亚型间P蛋白电泳迁移率的不同提供了一种可能。结论 我国RSV地方株与原型株之间的P蛋白无论在核苷酸水平还是在氨基酸水平均存在一定的变异。

Objective To get information about phosphoprotein (P) genes of RSV field strains isolated in China. Methods The complete nucleotide sequences of the P protein genes from six respiratory syncytial virus strains were determined with cDNA clones which had been amplified by RT PCR and cloned into PTZ18R plasmid vector and compared with those of previously published counterparts of A2 and CH18537 strains. Results The data indicated that there had high identities (>95%) at nucleotide and amino acid levels among the strains within the same subgroup; there were more divergence among strains (<85%) from different subgroups at nucleotide and amino acid levels of P genes,especially in the 3′ noncoding regions and the divergent domains. The analysis of hydrophobility indicated that there had difference from 50 to 100 amino acid of P proteins between A and B subtypes. Conclusion The analysis of the P genes confirm that there existed variability among RSV field strains and strains A2 and CH18537. The data described above revealed the characteristics of the P genes of RSV field strains isolated in China.