Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Hamburg, Germany.
Center for Structural Systems Biology, Hamburg, Germany.
PLoS Pathog. 2020 Jun 25;16(6):e1008588. doi: 10.1371/journal.ppat.1008588. eCollection 2020 Jun.
The human adenovirus type 5 (HAdV5) causes disease of the upper and lower respiratory tract. The early steps of HAdV5 entry up to genome replication in the host nucleus have been extensively studied. However, late stages of infection remain poorly understood. Here, we set out to elucidate the spatiotemporal orchestration of late adenovirus nuclear remodeling in living cells. We generated virus mutants expressing fluorescently tagged protein IX (pIX) and protein V (pV), a capsid and viral genome associated protein, respectively. We found that during progeny virion production both proteins localize to a membrane-less, nuclear compartment, which is highly impermeable such that in immunofluorescence microscopy antibodies can hardly penetrate it. We termed this compartment 'late virion accumulation compartment' (LVAC). Correlation between light- and electron microscopy revealed that the LVAC contains paracrystalline arrays of viral capsids that arrange tightly packed within a honeycomb-like organization of viral DNA. Live-cell microscopy as well as FRAP measurements showed that the LVAC is rigid and restricts diffusion of larger molecules, indicating that capsids are trapped inside.
人腺病毒 5 型（HAdV5）可引起上下呼吸道疾病。HAdV5 进入宿主细胞核并进行基因组复制的早期步骤已得到广泛研究。然而，感染的晚期阶段仍知之甚少。在这里，我们着手阐明活细胞中晚期腺病毒核重构的时空协调。我们生成了表达荧光标记蛋白 IX（pIX）和蛋白 V（pV）的病毒突变体，分别为衣壳和病毒基因组相关蛋白。我们发现，在子代病毒粒子产生过程中，这两种蛋白都定位于无膜的核区室，该区室高度不可渗透，以至于在免疫荧光显微镜下，抗体几乎无法穿透。我们将这个区室称为“晚期病毒粒子积累区室”（LVAC）。光镜和电子显微镜的相关性研究表明，LVAC 包含病毒衣壳的准晶阵列，这些衣壳在类似蜂窝状的病毒 DNA 组织中排列紧密。活细胞显微镜和 FRAP 测量表明，LVAC 是刚性的，限制了较大分子的扩散，表明衣壳被困在里面。
