【摘要】 目的筛选影响H5N1亚型甲型流感病毒对哺乳动物毒力变异的HA序列主要氨基酸位点。方法根据相关文献提供的实验结果,将54株H5N1病毒株按其对哺乳动物的毒力强弱分为高毒力组和低毒力组,在NCBI Genbank数据库中下载HA基因序列,用随机森林模型完成主要变异氨基酸位点的筛选。结果在HA序列中共筛选出8个关键位点,均位于HA1节段,分别为:279、102、228、156、154、172、140、8。位点154和156与其余几个关键位点间、位点140与172间均存在较强的协同交互作用,用上述关键位点重建的随机森林模型对病毒株毒力分类的准确率为83.33%。结论所筛选出的8个变异位点可能在决定H5N1病毒毒力上起关键作用,值得对其分子生物学作用机理做深入研究。更多还原

【Abstract】 Purpose To explore key amino acids sites on HA sequence which may determine the virulence of influenza a H5N1 for mammalian species. Methods Based on experimental results on mammalian species in archives,54 H5N1 viruses were divided into high or low virulence group.HA sequences of these viruses were downloaded from NCBI Genbank.Random Forest model was used to explore the hypervariable sites between groups. Results Sites 279,102,228,156,154,172,140 and 8 were selected from the HA gene as hypervariable sites,Strong positive interaction were detected between site 154,156 and other selected sites,as well as between site 172 and 140.The predict rate of random forest model using these 8 key sites was 83.33%. Conclusions The selected hypervariable sites may play a critical role in determining the virulence of H5N1 for mammalian species,related molecular mechanism should be searched thoroughly.更多还原