Research Laboratory for Infectious Diseases, Hospital Professor Edgar Santos, Federal University of Bahia, Salvador, Bahia, Brazil.
J Gen Virol. 2011 Mar;92(Pt 3):564-71. doi: 10.1099/vir.0.022525-0. Epub 2010 Dec 1.
Due to high genome plasticity, the evolutionary fate and geographical history of picornaviruses is hard to follow. Here, we determined the complete coding sequences of eight human parechoviruses (HPeV) of types 1, 5 and 6 directly from clinical samples from Brazil. The capsid genes of these strains were not remarkably different from European, North American and Japanese HPeV. Full genome analysis revealed frequent intertypic recombination in the non-structural genome region. In addition, evidence of recombination between viruses of the same type in the capsid-encoding genome region among HPeV1 and HPeV4 was obtained. Bayesian phylogenetic analysis indicated that strains without evidence of recombination with each other in any genome region were separated by no more than 35 years of circulation. Interestingly, in the 3C gene, all Brazilian parechoviruses grouped together regardless of serotype. The most recent common ancestor of these strains dated back 108 years, suggesting long-term endemicity of this particular P3 genome lineage in South America. Our results support the idea that picornavirus replicative genes acquire capsid proteins introduced by new strains. Under certain epidemiological conditions, replicative genes may be maintained in circumscript geographical regions.
由于基因组高度可塑性,小核糖核酸病毒的进化命运和地理历史难以追踪。在这里,我们直接从巴西的临床样本中确定了八种人类肠道病毒(HPeV)1、5 和 6 型的完整编码序列。这些毒株的衣壳基因与欧洲、北美和日本的 HPeV 没有显著差异。全基因组分析显示,非结构基因组区域频繁发生异型间重组。此外,还获得了 HPeV1 和 HPeV4 衣壳编码基因组区域内同种病毒之间重组的证据。贝叶斯系统发育分析表明,在任何基因组区域都没有证据表明彼此重组的菌株之间的分离时间不超过 35 年。有趣的是,在 3C 基因中,所有巴西肠道病毒都聚集在一起,无论血清型如何。这些菌株的最近共同祖先可以追溯到 108 年前,这表明该特定 P3 基因组谱系在南美洲长期流行。我们的研究结果支持小核糖核酸病毒复制基因获得新引入的衣壳蛋白的观点。在某些流行病学条件下,复制基因可能在限定的地理区域内得到维持。