Correlative multi-scale cryo-imaging unveils SARS-CoV-2 assembly and egress

• Published in: Nature communications 2021-07, Vol.12 (1), p.4629-4629, Article 4629
• Main Authors: Mendonça, Luiza, Howe, Andrew, Gilchrist, James B., Sheng, Yuewen, Sun, Dapeng, Knight, Michael L., Zanetti-Domingues, Laura C., Bateman, Benji, Krebs, Anna-Sophia, Chen, Long, Radecke, Julika, Li, Vivian D., Ni, Tao, Kounatidis, Ilias, Koronfel, Mohamed A., Szynkiewicz, Marta, Harkiolaki, Maria, Martin-Fernandez, Marisa L., James, William, Zhang, Peijun
• Format: Article
• Language: English
• Subjects: 101/28; 14; 631/326/421; 631/326/596/2148; 631/326/596/4130; 631/535/1258/1260; Animals; Assembly; Cellular structure; Chlorocebus aethiops; Context; Correlation; COVID-19 - epidemiology; COVID-19 - immunology; COVID-19 - virology; Cryoelectron Microscopy; Egress; Electron Microscope Tomography; Humanities and Social Sciences; Humans; Infections; Intermediates; Lamellae; multidisciplinary; Pandemics; Pandemics - prevention & control; RNA transport; RNA viruses; SARS-CoV-2 - immunology; SARS-CoV-2 - physiology; SARS-CoV-2 - ultrastructure; Scanning electron microscopy; Science; Science (multidisciplinary); Severe acute respiratory syndrome; Severe acute respiratory syndrome coronavirus 2; Soft x rays; Tomography; Vero Cells; Viral diseases; Virus Assembly - immunology; Virus Assembly - physiology; Virus Release - immunology; Virus Release - physiology; Virus Replication - immunology; Virus Replication - physiology; Viruses; X ray imagery
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-24887-y

Since the outbreak of the SARS-CoV-2 pandemic, there have been intense structural studies on purified viral components and inactivated viruses. However, structural and ultrastructural evidence on how the SARS-CoV-2 infection progresses in the native cellular context is scarce, and there is a lack of comprehensive knowledge on the SARS-CoV-2 replicative cycle. To correlate cytopathic events induced by SARS-CoV-2 with virus replication processes in frozen-hydrated cells, we established a unique multi-modal, multi-scale cryo-correlative platform to image SARS-CoV-2 infection in Vero cells. This platform combines serial cryoFIB/SEM volume imaging and soft X-ray cryo-tomography with cell lamellae-based cryo-electron tomography (cryoET) and subtomogram averaging. Here we report critical SARS-CoV-2 structural events – e.g. viral RNA transport portals, virus assembly intermediates, virus egress pathway, and native virus spike structures, in the context of whole-cell volumes revealing drastic cytppathic changes. This integrated approach allows a holistic view of SARS-CoV-2 infection, from the whole cell to individual molecules. In this study, Peijun Zhang and colleagues use cryoFIB/SEM volume imaging and soft x-ray cryo-tomography with cryo-electron tomography (cryoET) of cellular periphery, lamellae, and subtomogram averaging to place critical structural events in the SARS-CoV-2 infection cycle in the context of whole-cell images.