Plyusnin A, Vapalahti O, Lehväslaiho H, Apekina N, Mikhailova T, Gavrilovskaya I, Laakkonen J, Niemimaa J, Henttonen H, Brummer-Korvenkontio M
Haartman Institute, Department of Virology, Helsinki University, Finland.
Virus Res. 1995 Sep;38(1):25-41. doi: 10.1016/0168-1702(95)00038-r.
Reverse transcriptase polymerase chain reaction cloning and sequencing were used to determine the range of S gene/N protein variability in wild Puumala virus (PUU) strains and to study phylogenetic relationships between two groups of strains which originated from Finland and from European Russia. Analyses of the nucleotide and predicted amino acid sequences showed: (1) all PUU strains shared a common ancient ancestor; and (2) the more recent ancestors were different for the Finnish branch and the Russian branch of PUU strains. A cluster of amino acid substitutions in the N protein of Finnish strains was found; this cluster was located within a highly variable region of the molecule carrying B-cell epitopes (Vapalahti et al., J. Med. Virol., 1995, in press). Different levels of S gene/N protein diversity of PUU were revealed supporting the view of geographical clustering of genetic variants. Puumala virus from individual voles was found to be a complex mixture of closely related variants-quasispecies. The ratio of non-silent to silent nucleotide mutations registered in the S genes/N proteins of PUU quasispecies was 4- to 16-fold higher than that in Puumala virus strains, resulting in a more wide range of quasispecies N protein sequence diversity.
采用逆转录酶聚合酶链反应克隆和测序技术，以确定野生普马拉病毒（PUU）株中S基因/N蛋白的变异范围，并研究源自芬兰和俄罗斯欧洲部分的两组毒株之间的系统发育关系。对核苷酸和预测的氨基酸序列分析表明：（1）所有PUU毒株共有一个共同的古老祖先；（2）芬兰分支和俄罗斯分支的PUU毒株的近代祖先不同。在芬兰毒株的N蛋白中发现了一组氨基酸替换；该组位于携带B细胞表位的分子高变区内（Vapalahti等人，《医学病毒学杂志》，1995年，即将发表）。揭示了PUU的S基因/N蛋白不同程度的多样性，支持了遗传变异地理聚类的观点。发现来自单个田鼠的普马拉病毒是密切相关变异体——准种的复杂混合物。PUU准种的S基因/N蛋白中记录的非同义核苷酸突变与同义核苷酸突变的比率比普马拉病毒株高4至16倍，导致准种N蛋白序列多样性范围更广。
