PDF(Pubmed)
Abstract：
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a lipid-enveloped virus that acquires its lipid bilayer from the host cell it infects. SARS-CoV-2 can spread from cell to cell or from patient to patient by undergoing assembly and budding to form new virions. The assembly and budding of SARS-CoV-2 is mediated by several structural proteins known as envelope (E), membrane (M), nucleoprotein (N), and spike (S), which can form virus-like particles (VLPs) when co-expressed in mammalian cells. Assembly and budding of SARS-CoV-2 from the host ER-Golgi intermediate compartment is a critical step in the virus acquiring its lipid bilayer. To date, little information is available on how SARS-CoV-2 assembles and forms new viral particles from host membranes. In this study, we used several lipid binding assays and found the N protein can strongly associate with anionic lipids including phosphoinositides and phosphatidylserine. Moreover, we show lipid binding occurs in the N protein C-terminal domain, which is supported by extensive in silico analysis. We demonstrate anionic lipid binding occurs for both the free and the N oligomeric forms, suggesting N can associate with membranes in the nucleocapsid form. Based on these results, we present a lipid-dependent model based on in vitro, cellular, and in silico data for the recruitment of N to assembly sites in the lifecycle of SARS-CoV-2.
摘要：
严重急性呼吸道综合征冠状病毒2（SARS-CoV-2）是一种脂质包膜病毒，可从其感染的宿主细胞中获取其脂质双层。SARS-CoV-2可以通过进行组装和出芽以形成新的病毒体而在细胞之间或在患者之间传播。SARS-CoV-2的组装和出芽是由几种称为包膜（E）的结构蛋白介导的。膜(M),核蛋白（N）和刺突（S），当在哺乳动物细胞中共表达时,其可以形成病毒样颗粒(VLP)。SARS-CoV-2从宿主ER-高尔基体中间区室的组装和出芽是病毒获得其脂质双层的关键步骤。迄今为止,关于SARS-CoV-2如何从宿主膜组装并形成新病毒颗粒的信息很少。在这项研究中,我们使用了几种脂质结合测定法,发现N蛋白可以与阴离子脂质(包括磷酸肌醇和磷脂酰丝氨酸)强烈缔合.此外，我们显示脂质结合发生在N蛋白C末端结构域，这得到了广泛的计算机模拟分析的支持。我们证明了游离和N寡聚形式都发生阴离子脂质结合，表明N可以与核衣壳形式的膜缔合。基于这些结果,我们提出了一个基于体外的脂质依赖模型，在SARS-CoV-2的生命周期中，将N招募到组装地点的细胞和计算机数据。
