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bioRxiv · 10.1101/2023.09.15.557899

The SARS-CoV-2 nucleoprotein associates with anionic lipid membranes

Dutta, M.·Su, Y.·Voth, G. A.·Stahelin, R. V.
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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 find the N protein can strongly associate with anionic lipids including phosphoinositides and phosphatidylserine. Moreover, lipid binding is shown to occur in the N protein C-terminal domain, which is supported by extensive in silico analysis. Anionic lipid binding occurs for both the free and N oligomeric forms suggesting N can associate with membranes in the nucleocapsid form. Herein we present a lipid-dependent model based on in vitro, cellular and in silico data for the recruitment of N to M assembly sites in the lifecycle of SARS-CoV-2.

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Dutta, M., Su, Y., Voth, G. A., Stahelin, R. V.. 2023-09-15. The SARS-CoV-2 nucleoprotein associates with anionic lipid membranes. https://doi.org/10.1101/2023.09.15.557899

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