Phosphorylation toggles the SARS-CoV-2 nucleocapsid protein between two membrane-associated condensate states
The Nucleocapsid protein (N) of SARS-CoV-2 plays a critical role in the viral lifecycle by regulating RNA replication and by packaging the viral genome. N and RNA phase separate to form condensates that may be important for these functions. Both functions occur at membrane surfaces, but how N toggles between these two membrane-associated functional states is unclear. Here, we reveal that phosphorylation switches how N condensates interact with membranes, in part by modulating condensate material properties. Our studies also show that phosphorylation alters N's interaction with viral membrane proteins. We gain mechanistic insight through structural analysis and molecular simulations, which suggest phosphorylation induces a conformational change in N that softens condensate material properties. Together, our findings identify membrane association as a key feature of N condensates and provide mechanistic insights into the regulatory role of phosphorylation. Understanding this mechanism suggests potential therapeutic targets for COVID infection.
Authors
- Huan Wang (ORCID: https://orcid.org/0000-0001-7549-5026)
- Benjamin S. Schuster (ORCID: https://orcid.org/0000-0002-6468-8081)
- Andrea Soranno (ORCID: https://orcid.org/0000-0001-8394-7993)
- Mayur Barai
- Bruna Favetta (ORCID: https://orcid.org/0000-0002-3613-1665)
- N. Sanjeeva Murthy (ORCID: https://orcid.org/0000-0002-2324-5874)
- Jasmine Cubuk (ORCID: https://orcid.org/0000-0001-6915-8242)
- Haiyan Zheng (ORCID: https://orcid.org/0000-0003-1955-1817)
- Adam J. Gormley (ORCID: https://orcid.org/0000-0002-2884-725X)
- César E. Ramírez (ORCID: https://orcid.org/0000-0003-2707-7481)
- Arjun Singh (ORCID: https://orcid.org/0000-0001-6389-5540)
- Gregory L. Dignon (ORCID: https://orcid.org/0000-0001-8016-8652)
- Zheng Shi (ORCID: https://orcid.org/0000-0002-5214-1871)
Institutions
- Rutgers, The State University of New Jersey (US)
- Washington University in St. Louis (US)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-08-26
- DOI
- https://doi.org/10.1038/s41467-025-62922-4
- Citations
- 5
- Primary Topic
- RNA and protein synthesis mechanisms
- Type
- article
- Field-Weighted Citation Impact
- 4.03
Funders
- National Science Foundation
- U.S. Department of Energy
- National Institutes of Health
- Office of Science
- National Institute of General Medical Sciences
- Basic Energy Sciences
- Biological and Environmental Research
- Brookhaven National Laboratory