Characterization of SARS-CoV-2 N protein reveals multiple functional consequences of the C-terminal domain

Wu, C.; Qavi, A. J.; Hachim, A.; Kavian, N.; Cole, A. R.; Moyle, A. B.; Wagner, N. D.; Sweeney-Gibbons, J.; Rohrs, H. W.; Gross, M. L.; Peiris, J. S. M.; Basler, C. F.; Farnsworth, C. W.; Valkenburg, S. A.; Amarasinghe, G. K.; Leung, D. W.

doi:10.1101/2020.11.30.404905

bioRxiv · 10.1101/2020.11.30.404905

Characterization of SARS-CoV-2 N protein reveals multiple functional consequences of the C-terminal domain

Wu, C.·Qavi, A. J.·Hachim, A.·Kavian, N.·Cole, A. R.·Moyle, A. B.·Wagner, N. D.·Sweeney-Gibbons, J.·Rohrs, H. W.·Gross, M. L.·Peiris, J. S. M.·Basler, C. F.·Farnsworth, C. W.·Valkenburg, S. A.·Amarasinghe, G. K.·Leung, D. W.

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Abstract

Nucleocapsid protein (N) is the most abundant viral protein encoded by SARS-CoV-2, the causative agent of COVID-19. N plays key roles at different steps in the replication cycle and is used as a serological marker of infection. Here we characterize the biochemical properties of SARS-CoV-2 N. We define the N domains important for oligomerization and RNA binding that are associated with spherical droplet formation and suggest that N accessibility and assembly may be regulated by phosphorylation. We also map the RNA binding interface using hydrogen-deuterium exchange mass spectrometry. Finally, we find that the N protein C-terminal domain is the most immunogenic by sensitivity, based upon antibody binding to COVID-19 patient samples from the US and Hong Kong. Together, these findings uncover domain-specific insights into the significance of SARS-CoV-2 N and highlight the diagnostic value of using N domains as highly specific and sensitive markers of COVID-19.

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Wu, C., Qavi, A. J., Hachim, A., Kavian, N., Cole, A. R., Moyle, A. B., Wagner, N. D., Sweeney-Gibbons, J., Rohrs, H. W., Gross, M. L., Peiris, J. S. M., Basler, C. F., Farnsworth, C. W., Valkenburg, S. A., Amarasinghe, G. K., Leung, D. W.. 2020-11-30. Characterization of SARS-CoV-2 N protein reveals multiple functional consequences of the C-terminal domain. https://doi.org/10.1101/2020.11.30.404905

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