水稻条纹病毒中国分离物和日本分离物RNA1片段序列比较

 首次测定了我国水稻条纹叶枯病常年流行区的云南楚雄(CX)及病害暴发区的江苏洪泽(HZ)的RSV 2个分离物RNA1片段的全长序列,这2个分离物RNA1片段的全长序列均为8970 nts。同源性分析结果表明,HZ与日本T分离物的亲缘关系较CX与T分离物的亲缘关系更为接近。通过对纤细病毒属病毒RNA1编码的依赖于RNA的RNA聚合酶(RdRp)氨基酸序列分析的结果表明,该蛋白除了具有RNA聚合酶特征的基元序列结构外,还存在mRNA的转录过程中所采取的加帽起始机制的保守性结构域位点,这表明,纤细病毒属病毒和布尼安病毒科病毒及甲型流感病毒一样,都是采取加帽起始机制进行转录的。

Comparison of the RNA1 segments between Chinese isolates and Japanese isolates of Rice stripe virus

The complete nucleotide (nts) sequences of RNA1 of two isolates of Rice stripe virus (RSV), isolated from Chuxiong (CX), Yunnan Province, and Hongze (HZ), Jiangsu Province, were determined. RNAl of both CX and HZ isolates were 8970 nts. Comparison of the nucleotide and amino acid sequences of seven ORFs among these three isolates demonstrated that the closer phylogenetic relationship between HZ and T isolates than that between CX and T isolates. Comparison of the L proteins of Tenuiviruses RSV and Rice grassy stunt virus (RGSV) with those of Bunyaviruses indicated that Tenuiviruses were most closely related to the genus Phlebovirus. The alignment data showed that Tenuiviruses L protein shared with Bunyaviruses the three conserved regions corresponding to the so-called polymerase module. These comparisons also showed the existence of an additional fourth conserved region in the L protein of Tenuiviruses that contains at least two active sites, indicating that this region has an important role in the function of this protein. Further analysis showed that the two active sites were necessary for primer mRNA synthesis with cell-derived capped primers in influenza virus. The result indicated that Tenuiviruses could also have the cell-derived capped primer mechanisms.