云南省2014年狂犬病病毒G基因序列测定与分析

Sequencing analysis of the glycoprotein genome of rabies viruses isolated from Yunnan province of China in 2014

目的测定2014年云南省狂犬病病毒（RABV）的G基因序列,阐明它们的分子生物学特征。方法用RT-PCR法对RABV的G基因进行全序扩增,并对它们核苷酸序列和推导氨基酸序列进行同源性和进化树分析以及氨基酸位点分析。结果经序列测定,共获得16株RABV的G基因全序列。进化分析表明,本次云南RABV均为基因I型,与四川、广西及既往云南流行株亲缘关系较近,与东南亚流行株也具有较近的亲缘关系。云南株间的核苷酸和氨基酸同源性分别为99.4%～100.0%和99.2%～100.0%,它们与参考株的核苷酸和氨基酸同源性分别86.1%～99.8%和92.9%～99.8%。云南16株RABV的主要抗原性、嗜神经性、毒力及糖基化等功能位点均未发生明显改变,但信号肽氨基酸序列与参考株间差异较多。结论2014年云南RABV间无明显差异,均属于我国主要流行的基因I型中的中国I进化群。云南株RABV的G蛋白重要功能位点未发生变异,仍然保持其特有的抗原性和致病性等特征。

Objective To analyze the full-length genome of glycoprotein of rabies viruses isolated from Yunnan province of China in 2014. Methods The glycoprotein genes was amplified by RT-PCR and sequenced,the genetic homology,the phylogeny and amino acid sites were analyzed. Results The gene sequences of glycoprotein from 16 strains of rabies viruses isolated from Yunnan province of China in 2014 were acquired.The phylogenic analysis indicated that the isolates from Yunnan province showed a close genetic relationship with that isolated from neighbor provinces（Sichuan and Guangxi）and those previously isolated in Yunnan province;these strains also demonstrated a closer genetic relationship with the street strains isolated from Southeast Asia.The rate of their nucleotide homology and deduced amino acid homology were 99.4%-100.0% and99.2%-100.0%,respectively.Comparing to reference strains isolated from China or other countries,the nucleotide and deduced amino acid homology were 86.1%-99.8% and 92.9%-99.8%,respectively.No significant changes were found in sites related to antigenicity,pathogenic,virulence or glycosylation. ConclusionsRabies virus strains isolated from Yunnan province in 2014 showed a close genetic relationship and can be classified to clade China-I,the main clade of gene type I in China.No significant changes were found on major functional sites related to antigenicity and pathogenicity.