Specific viral RNA drives the SARS CoV-2 nucleocapsid to phase separate

Iserman, C.; Roden, C. A.; Boerneke, M.; Sealfon, R.; McLaughlin, G.; Jungreis, I.; Park, C. Y.; Boppana, A.; Fritch, E.; Hou, Y.; Theesfeld, C.; Troyanskaya, O.; Baric, R. S. G.; Sheahan, T. P.; Weeks, K.; Gladfelter, A.

doi:10.1101/2020.06.11.147199

bioRxiv · 10.1101/2020.06.11.147199

Specific viral RNA drives the SARS CoV-2 nucleocapsid to phase separate

Iserman, C.·Roden, C. A.·Boerneke, M.·Sealfon, R.·McLaughlin, G.·Jungreis, I.·Park, C. Y.·Boppana, A.·Fritch, E.·Hou, Y.·Theesfeld, C.·Troyanskaya, O.·Baric, R. S. G.·Sheahan, T. P.·Weeks, K.·Gladfelter, A.

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Abstract

A mechanistic understanding of the SARS-CoV-2 viral replication cycle is essential to develop new therapies for the COVID-19 global health crisis. In this study, we show that the SARS-CoV-2 nucleocapsid protein (N-protein) undergoes liquid-liquid phase separation (LLPS) with the viral genome, and propose a model of viral packaging through LLPS. N-protein condenses with specific RNA sequences in the first 1000 nts (5-End) under physiological conditions and is enhanced at human upper airway temperatures. N-protein condensates exclude non-packaged RNA sequences. We comprehensively map sites bound by N-protein in the 5-End and find preferences for single-stranded RNA flanked by stable structured elements. Liquid-like N-protein condensates form in mammalian cells in a concentration-dependent manner and can be altered by small molecules. Condensation of N-protein is sequence and structure specific, sensitive to human body temperature, and manipulatable with small molecules thus presenting screenable processes for identifying antiviral compounds effective against SARS-CoV-2.

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Iserman, C., Roden, C. A., Boerneke, M., Sealfon, R., McLaughlin, G., Jungreis, I., Park, C. Y., Boppana, A., Fritch, E., Hou, Y., Theesfeld, C., Troyanskaya, O., Baric, R. S. G., Sheahan, T. P., Weeks, K., Gladfelter, A.. 2020-06-12. Specific viral RNA drives the SARS CoV-2 nucleocapsid to phase separate. https://doi.org/10.1101/2020.06.11.147199

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