Ng Stella S F, Li Olive T W, Cheung Timothy K W, Malik Peiris J S, Poon Leo L M
State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Hong Kong SAR, China.
Virol J. 2008 Jan 11;5:2. doi: 10.1186/1743-422X-5-2.
The initiation of transcription and replication of influenza A virus requires the 5' and 3' ends of vRNA. Here, the role of segment-specific non-coding sequences of influenza A virus on viral RNA synthesis was studied. Recombinant viruses, with the nonstructural protein (NS) segment-specific non-coding sequences replaced by the corresponding sequences of the neuraminidase (NA) segment, were characterized. The NS and NA vRNA levels in cells infected with these mutants were much higher than those of the wild type, whereas the NS and NA mRNA levels of the mutants were comparable to the wild-type levels. By contrast, the PB2 vRNA and mRNA levels of all the tested viruses were similar, indicating that vRNA with heterologous segment-specific non-coding sequences was not affected by the mutations. The observations suggested that, with the cooperation between the homologous 5' and 3'segment-specific sequences, the introduced mutations could specifically enhance the replication of NA and NS vRNA.
甲型流感病毒的转录和复制起始需要病毒RNA（vRNA）的5'和3'末端。在此，研究了甲型流感病毒特定片段的非编码序列在病毒RNA合成中的作用。对重组病毒进行了表征，这些重组病毒的非结构蛋白（NS）片段特定非编码序列被神经氨酸酶（NA）片段的相应序列所取代。感染这些突变体的细胞中NS和NA vRNA水平远高于野生型，而突变体的NS和NA mRNA水平与野生型水平相当。相比之下，所有测试病毒的PB2 vRNA和mRNA水平相似，表明具有异源片段特定非编码序列的vRNA不受这些突变影响。这些观察结果表明，在同源的5'和3'片段特定序列的协同作用下，引入的突变可特异性增强NA和NS vRNA的复制。
