School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom.
Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom.
PLoS Pathog. 2018 Jan 19;14(1):e1006845. doi: 10.1371/journal.ppat.1006845. eCollection 2018 Jan.
In order to multiply and cause disease a virus must transport its genome from outside the cell into the cytosol, most commonly achieved through the endocytic network. Endosomes transport virus particles to specific cellular destinations and viruses exploit the changing environment of maturing endocytic vesicles as triggers to mediate genome release. Previously we demonstrated that several bunyaviruses, which comprise the largest family of negative sense RNA viruses, require the activity of cellular potassium (K+) channels to cause productive infection. Specifically, we demonstrated a surprising role for K+ channels during virus endosomal trafficking. In this study, we have used the prototype bunyavirus, Bunyamwera virus (BUNV), as a tool to understand why K+ channels are required for progression of these viruses through the endocytic network. We report three major findings: First, the production of a dual fluorescently labelled bunyavirus to visualize virus trafficking in live cells. Second, we show that BUNV traffics through endosomes containing high [K+] and that these K+ ions influence the infectivity of virions. Third, we show that K+ channel inhibition can alter the distribution of K+ across the endosomal system and arrest virus trafficking in endosomes. These data suggest high endosomal [K+] is a critical cue that is required for virus infection, and is controlled by cellular K+ channels resident within the endosome network. This highlights cellular K+ channels as druggable targets to impede virus entry, infection and disease.
为了进行复制并引发疾病，病毒必须将其基因组从细胞外部运输到细胞质中，这通常是通过内吞网络来实现的。内体将病毒颗粒运输到特定的细胞目的地，病毒利用成熟内吞体环境的变化作为触发因素来介导基因组释放。此前我们证明，几种 Bunyaviruses（包含最大的负义 RNA 病毒家族）需要细胞钾 (K+) 通道的活性才能引起有性感染。具体来说，我们在病毒内体运输过程中发现了钾通道的惊人作用。在这项研究中，我们使用了模式 Bunyavirus（Bunyamwera 病毒，BUNV）作为工具，以了解为什么钾通道对于这些病毒通过内吞网络的进展是必需的。我们报告了三个主要发现：首先，生产了一种双荧光标记的 Bunyavirus，以可视化活细胞中的病毒运输。其次，我们表明 BUNV 在内体中运输，其中含有高 [K+]，并且这些 K+ 离子影响病毒粒子的感染力。第三，我们表明钾通道抑制可以改变内体系统中 K+ 的分布，并在内体中阻断病毒运输。这些数据表明，高内体 [K+] 是病毒感染所必需的关键线索，并且由内体网络中存在的细胞钾通道控制。这突显了细胞钾通道作为阻碍病毒进入、感染和疾病的可用药靶。
