title: Modular organization of SARS coronavirus nucleocapsid protein.
abstract: The SARS-CoV nucleocapsid (N) protein is a major antigen in severe acute respiratory syndrome. It binds to the viral RNA genome and forms the ribonucleoprotein core. The SARS-CoV N protein has also been suggested to be involved in other important functions in the viral life cycle. Here we show that the N protein consists of two non-interacting structural domains, the N-terminal RNA-binding domain (RBD) (residues 45-181) and the C-terminal dimerization domain (residues 248-365) (DD), surrounded by flexible linkers. The C-terminal domain exists exclusively as a dimer in solution. The flexible linkers are intrinsically disordered and represent potential interaction sites with other protein and protein-RNA partners. Bioinformatics reveal that other coronavirus N proteins could share the same modular organization. This study provides information on the domain structure partition of SARS-CoV N protein and insights into the differing roles of structured and disordered regions in coronavirus nucleocapsid proteins.
authors.affiliation: Institute of Biomedical Sciences, Academia Sinica, Nankang, Taipei, Taiwan, ROC.
authors.forename: Chung-ke
authors.initials: CK
authors.lastname: Chang
authors.forename: Shih-Che
authors.initials: SC
authors.lastname: Sue
authors.forename: Tsan-hung
authors.initials: TH
authors.lastname: Yu
authors.forename: Chiu-Min
authors.initials: CM
authors.lastname: Hsieh
authors.forename: Cheng-Kun
authors.initials: CK
authors.lastname: Tsai
authors.forename: Yen-Chieh
authors.initials: YC
authors.lastname: Chiang
authors.forename: Shin-jye
authors.initials: SJ
authors.lastname: Lee
authors.forename: Hsin-hao
authors.initials: HH
authors.lastname: Hsiao
authors.forename: Wen-Jin
authors.initials: WJ
authors.lastname: Wu
authors.forename: Wei-Lun
authors.initials: WL
authors.lastname: Chang
authors.forename: Chun-Hung
authors.initials: CH
authors.lastname: Lin
authors.forename: Tai-huang
authors.initials: TH
authors.lastname: Huang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000956:Antigens, Viral / Q000737:chemistry* / Q000235:genetics; D000086462:Coronavirus Nucleocapsid Proteins; D006801:Humans; D008969:Molecular Sequence Data; D019590:Nucleocapsid Proteins / Q000737:chemistry* / Q000235:genetics; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D000956:Antigens, Viral; D000086462:Coronavirus Nucleocapsid Proteins; D019590:Nucleocapsid Proteins; D010446:Peptide Fragments