Reconstitution of the SARS-CoV-2 ribonucleosome provides insights into genomic RNA packaging and regulation by phosphorylation.
J Biol Chem
; 298(11): 102560, 2022 11.
Article
em En
| MEDLINE
| ID: mdl-36202211
ABSTRACT
The nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 is responsible for compaction of the â¼30-kb RNA genome in the â¼90-nm virion. Previous studies suggest that each virion contains 35 to 40 viral ribonucleoprotein (vRNP) complexes, or ribonucleosomes, arrayed along the genome. There is, however, little mechanistic understanding of the vRNP complex. Here, we show that N protein, when combined in vitro with short fragments of the viral genome, forms 15-nm particles similar to the vRNP structures observed within virions. These vRNPs depend on regions of N protein that promote protein-RNA and protein-protein interactions. Phosphorylation of N protein in its disordered serine/arginine region weakens these interactions to generate less compact vRNPs. We propose that unmodified N protein binds structurally diverse regions in genomic RNA to form compact vRNPs within the nucleocapsid, while phosphorylation alters vRNP structure to support other N protein functions in viral transcription.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
SARS-CoV-2
/
COVID-19
Limite:
Humans
Idioma:
En
Ano de publicação:
2022
Tipo de documento:
Article