PT - JOURNAL ARTICLE AU - Milan Zachrdla AU - Adriana Savastano AU - Alain Ibáñez de Opakua AU - Maria-Sol Cima-Omori AU - Markus Zweckstetter TI - Contributions of the N-terminal intrinsically disordered region of the SARS-CoV-2 nucleocapsid protein to RNA-induced phase separation AID - 10.1101/2022.03.30.486418 DP - 2022 Jan 01 TA - bioRxiv PG - 2022.03.30.486418 4099 - http://biorxiv.org/content/early/2022/03/31/2022.03.30.486418.short 4100 - http://biorxiv.org/content/early/2022/03/31/2022.03.30.486418.full AB - SARS-CoV-2 nucleocapsid protein is an essential structural component of mature virions, encapsulating the genomic RNA and modulating RNA transcription and replication. Several of its activities might be associated with the protein’s ability to undergo liquid-liquid phase separation. NSARS-CoV-2 contains an intrinsically disordered region at its N-terminus (NTE) that can be phosphorylated and is affected by disease-relevant mutations. Here we show that NTE deletion decreases the range of RNA concentrations that can induce phase separation of NSARS-CoV-2. In addition, deletion of the prion-like NTE allows NSARS-CoV-2 droplets to retain their liquid-like nature during incubation. We further demonstrate that RNA-binding engages multiple parts of the NTE and changes NTE’s structural properties. The results form the foundation to characterize the impact of N-terminal mutations and post-translational modifications on the molecular properties of the SARS-CoV-2 nucleocapsid protein.Statement The nucleocapsid protein of SARS-CoV-2 plays an important role in both genome packaging and viral replication upon host infection. Replication has been associated with RNA-induced liquid-liquid phase separation of the nucleocapsid protein. We present insights into the role of the N-terminal part of the nucleocapsid protein in the protein’s RNA-mediated liquid-liquid phase separation.Competing Interest StatementThe authors have declared no competing interest.