Structure of the SARS Coronavirus Nucleocapsid Protein RNA-binding Dimerization Domain Suggests a Mechanism for Helical Packaging of Viral RNA

摘要: Coronavirus nucleocapsid proteins are basic that encapsulate viral genomic RNA to form part of the virus structure. The protein SARS-CoV is highly antigenic and associated with several host-cell interactions. Our previous studies using nuclear magnetic resonance revealed domain organization protein. has been shown bind N-terminal (NTD), although recently C-terminal half also implicated in binding. Here, we report (CTD), spanning residues 248-365 (NP248-365), had stronger nucleic acid-binding activity than NTD. To determine molecular basis this activity, have solved crystal structure NP248-365 region. Residues 248-280 a positively charged groove similar found infectious bronchitis (IBV) Furthermore, surface area larger construct IBV. Interactions between rest molecule stabilize formation an octamer asymmetric unit. Packing octamers forms two parallel, helical grooves, which may be oligonucleotide attachment sites, suggests mechanism for packaging virus.