Duncan Roy, Corcoran Jennifer, Shou Jingyun, Stoltz Don
Department of Microbiology and Immunology, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada B3H 4H7.
Virology. 2004 Feb 5;319(1):131-40. doi: 10.1016/j.virol.2003.10.025.
The fusogenic subgroup of orthoreoviruses contains most of the few known examples of non-enveloped viruses capable of inducing syncytium formation. The only unclassified orthoreoviruses at the species level represent several fusogenic reptilian isolates. To clarify the relationship of reptilian reoviruses (RRV) to the existing fusogenic and nonfusogenic orthoreovirus species, we undertook a characterization of a python reovirus isolate. Biochemical, biophysical, and biological analyses confirmed the designation of this reptilian reovirus (RRV) isolate as an unclassified fusogenic orthoreovirus. Sequence analysis revealed that the RRV S1 and S3 genome segments contain a novel conserved 5'-terminal sequence not found in other orthoreovirus species. In addition, the gene arrangement and the coding potential of the bicistronic RRV S1 genome segment differ from that of established orthoreovirus species, encoding a predicted homologue of the reovirus cell attachment protein and a unique 125 residue p14 protein. The RRV S3 genome segment encodes a homologue of the reovirus sigma-class major outer capsid protein, although it is highly diverged from that of other orthoreovirus species (amino acid identities of only 16-25%). Based on sequence analysis, biological properties, and phylogenetic analysis, we propose this python reovirus be designated as the prototype strain of a fifth species of orthoreoviruses, the reptilian reoviruses.
正呼肠孤病毒的融合亚群包含了少数已知的能够诱导合胞体形成的无包膜病毒实例中的大多数。在物种水平上唯一未分类的正呼肠孤病毒代表了几种融合性爬行动物分离株。为了阐明爬行动物呼肠孤病毒（RRV）与现有的融合性和非融合性正呼肠孤病毒物种之间的关系，我们对一种蟒蛇呼肠孤病毒分离株进行了特性分析。生化、生物物理和生物学分析证实，这种爬行动物呼肠孤病毒（RRV）分离株被指定为一种未分类的融合性正呼肠孤病毒。序列分析表明，RRV S1和S3基因组片段包含一个在其他正呼肠孤病毒物种中未发现的新的保守5'-末端序列。此外，双顺反子RRV S1基因组片段的基因排列和编码潜能与已确立的正呼肠孤病毒物种不同，它编码一种预测的呼肠孤病毒细胞附着蛋白同源物和一种独特的125个残基的p14蛋白。RRV S3基因组片段编码呼肠孤病毒σ类主要外衣壳蛋白的同源物，尽管它与其他正呼肠孤病毒物种的同源物高度不同（氨基酸同一性仅为16-25%）。基于序列分析、生物学特性和系统发育分析，我们建议将这种蟒蛇呼肠孤病毒指定为正呼肠孤病毒第五个物种——爬行动物呼肠孤病毒的原型株。
