Czeglédi Alíz, Ujvári Dorina, Somogyi Eszter, Wehmann Eniko, Werner Ortrud, Lomniczi Béla
Veterinary Medical Research Institute of the Hungarian Academy of Sciences, PO Box 18, Budapest 1581, Hungary.
Virus Res. 2006 Sep;120(1-2):36-48. doi: 10.1016/j.virusres.2005.11.009.
The goal of the study was to establish if there was a relationship between molecular patterns and virus evolution. Therefore the complete genome sequence of two distinct apathogenic Newcastle disease virus (NDV) strains was determined and a third genome size category, containing 15,198 nucleotides, was recognized. Phylogenetic analysis revealed that two major separations resulting in three genome size categories occurred during the history of NDV. An ancient division in the primordial reservoir (wild waterbird species) led to two basal sister clades, class I and II, with genome sizes 15,198 (due to a 12 nucleotide insert in the phosphoprotein gene) and 15,186 nucleotides, respectively. Ancestors of only class II viruses colonized chicken populations and subsequently converted to virulent forms. These took place more than once and resulted in an early lineage [including genotypes I-IV and H33(W)] with genome size of 15,186 nucleotides. A second division occurred in the 20th century in the secondary (chicken) host. This gave rise to the branching-off of a clade (including recent genotypes V-VIII consisting of only pathogenic viruses) with the concomitant insertion of six nucleotides into the 5' non-coding region of the nucleoprotein gene thereby increasing the genome size to 15,192 nucleotides.
该研究的目的是确定分子模式与病毒进化之间是否存在关联。因此，测定了两种不同的非致病性新城疫病毒（NDV）毒株的完整基因组序列，并识别出了一个包含15,198个核苷酸的第三种基因组大小类别。系统发育分析表明，在新城疫病毒的历史中发生了两次导致三种基因组大小类别的主要分化。原始宿主（野生水鸟物种）中的一次古老分化产生了两个基部姐妹进化枝，即I类和II类，其基因组大小分别为15,198个核苷酸（由于磷蛋白基因中有12个核苷酸的插入）和15,186个核苷酸。只有II类病毒的祖先定殖于鸡群中，并随后转变为强毒株形式。这种情况发生了不止一次，并产生了一个基因组大小为15,186个核苷酸的早期谱系[包括基因型I-IV和H33(W)]。第二次分化发生在20世纪的第二宿主（鸡）中。这导致了一个进化枝（包括仅由致病性病毒组成的近期基因型V-VIII）的分支，同时在核蛋白基因的5'非编码区插入了六个核苷酸，从而使基因组大小增加到15,192个核苷酸。
