Department of Special Pathogens, International Research Center for Infectious Diseases, Institute of Medical Science, University of Tokyo, Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
Nat Commun. 2012 Jan 24;3:639. doi: 10.1038/ncomms1647.
The influenza A virus genome consists of eight single-stranded negative-sense RNA (vRNA) segments. Although genome segmentation provides advantages such as genetic reassortment, which contributes to the emergence of novel strains with pandemic potential, it complicates the genome packaging of progeny virions. Here we elucidate, using electron tomography, the three-dimensional structure of ribonucleoprotein complexes (RNPs) within progeny virions. Each virion is packed with eight well-organized RNPs that possess rod-like structures of different lengths. Multiple interactions are found among the RNPs. The position of the eight RNPs is not consistent among virions, but a pattern suggests the existence of a specific mechanism for assembly of these RNPs. Analyses of budding progeny virions suggest two independent roles for the viral spike proteins: RNP association on the plasma membrane and the subsequent formation of the virion shell. Our data provide further insights into the mechanisms responsible for segmented-genome packaging into virions.
甲型流感病毒基因组由八个单链负义 RNA（vRNA）片段组成。尽管基因组分段具有遗传重配的优势，有助于产生具有大流行潜力的新型毒株，但它使子代病毒的基因组包装复杂化。在这里，我们使用电子断层摄影术阐明了子代病毒中核糖核蛋白复合物（RNP）的三维结构。每个病毒都包装有八个组织良好的 RNP，它们具有不同长度的棒状结构。在 RNP 之间发现了多种相互作用。八个 RNP 在病毒之间的位置不一致，但有一种模式表明存在一种特定的机制来组装这些 RNP。对出芽子代病毒的分析表明，病毒刺突蛋白具有两个独立的作用：在质膜上与 RNP 结合，以及随后形成病毒壳。我们的数据为负责将分段基因组包装到病毒中的机制提供了进一步的见解。
