Ludwig Alexander, Nguyen Tra Huong, Leong Daniel, Ravi Laxmi Iyer, Tan Boon Huan, Sandin Sara, Sugrue Richard J
School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551.
J Cell Sci. 2017 Mar 15;130(6):1037-1050. doi: 10.1242/jcs.198853. Epub 2017 Feb 2.
Respiratory syncytial virus (RSV) is an enveloped virus that assembles into filamentous virus particles on the surface of infected cells. Morphogenesis of RSV is dependent upon cholesterol-rich (lipid raft) membrane microdomains, but the specific role of individual raft molecules in RSV assembly is not well defined. Here, we show that RSV morphogenesis occurs within caveolar membranes and that both caveolin-1 and cavin-1 (also known as PTRF), the two major structural and functional components of caveolae, are actively recruited to and incorporated into the RSV envelope. The recruitment of caveolae occurred just prior to the initiation of RSV filament assembly, and was dependent upon an intact actin network as well as a direct physical interaction between caveolin-1 and the viral G protein. Moreover, cavin-1 protein levels were significantly increased in RSV-infected cells, leading to a virus-induced change in the stoichiometry and biophysical properties of the caveolar coat complex. Our data indicate that RSV exploits caveolae for its assembly, and we propose that the incorporation of caveolae into the virus contributes to defining the biological properties of the RSV envelope.
呼吸道合胞病毒（RSV）是一种包膜病毒，在受感染细胞表面组装成丝状病毒颗粒。RSV的形态发生依赖于富含胆固醇的（脂筏）膜微区，但单个筏分子在RSV组装中的具体作用尚不清楚。在这里，我们表明RSV形态发生发生在小窝膜内，并且小窝的两个主要结构和功能成分小窝蛋白-1和小窝结合蛋白-1（也称为PTRF）被积极招募并整合到RSV包膜中。小窝的招募发生在RSV丝状组装开始之前，并且依赖于完整的肌动蛋白网络以及小窝蛋白-1与病毒G蛋白之间的直接物理相互作用。此外，在RSV感染的细胞中小窝结合蛋白-1的蛋白水平显著增加，导致病毒诱导的小窝衣被复合物的化学计量和生物物理性质的变化。我们的数据表明RSV利用小窝进行组装，并且我们提出将小窝整合到病毒中有助于定义RSV包膜的生物学特性。
