Blanchard C L, Higgins T J, Anderson B J
School of Science and Technology, Charles Sturt University, Wagga, Australia.
Arch Virol. 1997;142(6):1273-83. doi: 10.1007/s007050050159.
Primer extension analysis was used to determine the presence of RNAs 4A and 5 in tomato aspermy virus (TAV) and both subgroups of cucumber mosaic virus (CMV). RNAs 4A and 5 were detected in TAV and all CMV strains (representative of both subgroups) that were analysed, except for one subgroup I CMV strain which lacked detectable RNA 5. In subgroup II CMV strains the RNA 5 population was found to consist of two sequence variants. Comparison of the RNA 5 sequences from TAV and CMV indicated that TAV and subgroup II CMV RNA 5 share a much greater degree of sequence similarity than either has with subgroup I RNA 5. RNA 4A and the encoded 2b protein appear to be unique to the cucumovirus genus of the tripartite viruses, which share an otherwise common genome structure, and may have played a role in the evolutionary origin of this genus.
采用引物延伸分析来确定番茄不孕病毒（TAV）以及黄瓜花叶病毒（CMV）两个亚组中RNA 4A和5的存在情况。在分析的TAV和所有CMV毒株（代表两个亚组）中均检测到了RNA 4A和5，但有一株I亚组CMV毒株未检测到可检测的RNA 5。在II亚组CMV毒株中，发现RNA 5群体由两个序列变体组成。对TAV和CMV的RNA 5序列进行比较表明，TAV和II亚组CMV的RNA 5序列相似程度远高于它们与I亚组RNA 5的相似程度。RNA 4A和编码的2b蛋白似乎是三分体病毒黄瓜花叶病毒属所特有的，这些病毒共享一个其他方面常见的基因组结构，并且可能在该属的进化起源中发挥了作用。
