Department of Microbiology, Mount Sinai School of Medicine, New York, New York, USA.
J Virol. 2012 May;86(9):5366-70. doi: 10.1128/JVI.06722-11. Epub 2012 Feb 15.
We generated influenza A viruses expressing mutant NS1 proteins unable to activate phosphoinositide 3-kinase (PI3K) in two mouse-lethal strains. The recombinant A/Puerto Rico/8/34 (rPR8) mutant virus strain was attenuated and caused reduced morbidity/mortality. For the recombinant A/WSN/33 (rWSN) virus strain, the inability to stimulate PI3K had minimal impact on replication or morbidity/mortality. Cell-based assays revealed subtly distinct intracellular sites of NS1 localization and PI3K activation between the strains. We hypothesize that specific spatially regulated NS1-activated PI3K signaling, rather than simply the total level of active PI3K, is important for virus replication and virulence.
我们生成了表达突变 NS1 蛋白的甲型流感病毒,这些突变 NS1 蛋白无法激活磷酸肌醇 3-激酶(PI3K),所用病毒株为两种能致人死亡的小鼠流感病毒株。重组 A/Puerto Rico/8/34(rPR8)突变病毒株毒力减弱,导致发病率/死亡率降低。对于重组 A/WSN/33(rWSN)病毒株,无法刺激 PI3K 对其复制或发病率/死亡率的影响极小。基于细胞的检测表明,两种病毒株 NS1 定位和 PI3K 激活的细胞内位置存在微妙差异。我们假设,特定的空间调节 NS1 激活的 PI3K 信号,而不是单纯的总活性 PI3K 水平,对病毒复制和毒力很重要。