新分离5株狂犬病病毒街毒株N和G基因的序列分析

目的分析我国新分离的5株狂犬病病毒(RV)街毒株基因序列及分子流行病学状况。方法采用RT-PCR法从疑似狂犬的犬脑组织内获得N和G基因cDNA的全序列并进行测序,将所得结果与已发表的国内外代表性毒株相应基因进行核苷酸和推导氨基酸序列比较。结果5株均含有完整N基因序列,3株含有完整G基因序列。与国内外发表的部分毒株比较,5株街毒N基因的核苷酸同源性在98.1%～99.9%之间,推导氨基酸同源性在99.5%～100%之间。将5株街毒与人用疫苗株3aG、PV株的N基因进行比较,核苷酸同源性在86.2%～86.7%之间,氨基酸同源性在95.1%～95.5%之间;而与人用疫苗株CTN比较,核苷酸同源性在89.4%～89.6%之间,氨基酸同源性在98.2%～98.6%之间。3株街毒G基因的核苷酸同源性在98.5%～99.4%之间,推导氨基酸同源性在99.6%～100%之间。将3株街毒与人用疫苗株aG、PV和兽用疫苗株ERA的G基因进行比较,核苷酸同源性在82.8%～83.1%之间,氨基酸同源性在88.0%～90.1%之间;而与人用疫苗株CTN比较,核苷酸同源性在86.7%～87.1%之间,氨基酸同源性均为92.0%。结论新分离街毒株基因未发生较大变异,与CTN的同源性高于与aG株和PV株。

Sequencing of N and G Genes of Five Rabies Street Virus Strains Isolated Recently in China

Objective To analyze the gene sequences and molecular epidemiology of five rabies street strains isolated recently in China.Methods The full-lengths of N and G genes were amplified from the brain tissues of dogs with doubtful rabies by RT-PCR and sequenced,and the results were compared with the nucleotide and deduced amino acid sequences of representative strains reported.Results All the five isolates contained full-length of N gene fragment,of which 3 contained full-length of G gene fragment.The homologies of nucleotides and amino acids of N genes of the five isolates were 98.1%-99.9% and 99.5%-100% respectively. The homologies of nucleotides and amino acids of N genes of the five isolates were 86.2%-86.7% and 95.1%-95.5% to those of 3aG and PV strains,and 89.4%-89.6% and 98.2%-98.6% to those of CTN strain,respectively.The homologies of nucleotides and amino acids of G gene of the three isolates were 98.5%-99.4% and 99.6%-100% respectively. The homologies of nucleotides and amino acids of G genes of the three isolates were 82.8%-83.1% and 88.0%-90.1% to those of aG,PV and ERA strains,and 86.7%-87.1% and 92.0% to those of CTN strain respectively.Conclusion Few variation was observed in the five rabies street virus strains isolated recently in China.The homologies of the five isolates of CTN strain were significantly higher than those to aG and PV strains.