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DOE OSTI · 2470773

Rapid assessment of SARS-CoV-2–evolved variants using virus-like particles

Abstract

Efforts to determine why new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants demonstrate improved fitness have been limited to analyzing mutations in the spike (S) protein with the use of S-pseudotyped particles. In this study, we show that SARS-CoV-2 virus-like particles (SC2-VLPs) can package and deliver exogenous transcripts, enabling analysis of mutations within all structural proteins and at multiple steps in the viral life cycle. In SC2-VLPs, four nucleocapsid (N) mutations found universally in more-transmissible variants independently increased messenger RNA delivery and expression ~10-fold, and in a reverse genetics model, the serine-202→arginine (S202R) and arginine-203→methionine (R203M) mutations each produced >50 times as much virus. SC2-VLPs provide a platform for rapid testing of viral variants outside of a biosafety level 3 setting and demonstrate N mutations and particle assembly to be mechanisms that could explain the increased spread of variants, including B.1.617.2 (Delta, which contains the R203M mutation).

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BibTeXRIS

Syed, Abdullah M., Taha, Taha Y., Tabata, Takako, Chen, Irene P., Ciling, Alison, Khalid, Mir M., Sreekumar, Bharath, Chen, Pei-Yi, Hayashi, Jennifer M., Soczek, Katarzyna M., Ott, Melanie, Doudna, Jennifer A.. 2021-11-04. Rapid assessment of SARS-CoV-2–evolved variants using virus-like particles. https://doi.org/10.1126/science.abl6184

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