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bioRxiv · 10.1101/2025.01.27.635166

The Interplay of Furin Cleavage and D614G in Modulating SARS-CoV-2 Spike Protein Dynamics

Shoemaker, S. R.·Luo, M.·Dam, K.-M. A.·Pak, J. E.·Hoffmann, M. A. G.·Marqusee, S.
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Abstract

We report a detailed analysis of the full-length SARS-CoV-2 spike dynamics within a native-like membrane environment and variants inaccessible to studies on soluble constructs by conducting hydrogen-deuterium exchange mass spectrometry (HDX-MS) on enveloped virus-like particles (eVLPs) displaying various spike constructs. We find that the previously identified open-interface trimer conformation is sampled in all eVLP-displayed spike variants studied including sequences from engineered vaccine constructs and native viral sequences. The D614G mutation, which arose early in the pandemic, favors the canonical closed-interface prefusion conformation, potentially mitigating premature S1 shedding in the presence of a cleaved furin site and providing an evolutionary advantage to the virus. Remarkably, furin cleavage at the S1/S2 boundary allosterically increases the flexibility of the S2 site, which may facilitate increased TMPRSS2 processing, enhancing viral infectivity. The use of eVLPs in HDX-MS studies provides a powerful platform for studying viral and membrane proteins in near-native environments.

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Shoemaker, S. R., Luo, M., Dam, K.-M. A., Pak, J. E., Hoffmann, M. A. G., Marqusee, S.. 2025-01-28. The Interplay of Furin Cleavage and D614G in Modulating SARS-CoV-2 Spike Protein Dynamics. https://doi.org/10.1101/2025.01.27.635166

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