title: Coronavirus nucleocapsid protein is an RNA chaperone.
abstract: RNA chaperones are nonspecific nucleic acid binding proteins with long disordered regions that help RNA molecules to adopt its functional conformation. Coronavirus nucleoproteins (N) are nonspecific RNA-binding proteins with long disordered regions. Therefore, we investigated whether transmissible gastroenteritis coronavirus (TGEV) N protein was an RNA chaperone. Purified N protein enhanced hammerhead ribozyme self-cleavage and nucleic acids annealing, which are properties that define RNA chaperones. In contrast, another RNA-binding protein, PTB, did not show these activities. N protein chaperone activity was blocked by specific monoclonal antibodies. Therefore, it was concluded that TGEV N protein is an RNA chaperone. In addition, we have shown that purified severe acute respiratory syndrome (SARS)-CoV N protein also has RNA chaperone activity. In silico predictions of disordered domains showed a similar pattern for all coronavirus N proteins evaluated. Altogether, these data led us to suggest that all coronavirus N proteins might be RNA chaperones.
authors.affiliation: Centro Nacional de Biotecnología, CSIC, Department of Molecular and Cell Biology, Campus Universidad Autónoma, Darwin 3, Cantoblanco, 28049 Madrid, Spain.
authors.forename: Sonia
authors.initials: S
authors.lastname: Zúñiga
authors.forename: Isabel
authors.initials: I
authors.lastname: Sola
authors.forename: Jose L
authors.initials: JL
authors.lastname: Moreno
authors.forename: Patricia
authors.initials: P
authors.lastname: Sabella
authors.forename: Juan
authors.initials: J
authors.lastname: Plana-Durán
authors.forename: Luis
authors.initials: L
authors.lastname: Enjuanes
mesh_terms: D018833:Chaperonins / Q000737:chemistry / Q000378:metabolism; D017934:Coronavirus / Q000737:chemistry*; D000086462:Coronavirus Nucleocapsid Proteins; D016679:Genome, Viral / Q000502:physiology; D018832:Molecular Chaperones / Q000737:chemistry / Q000378:metabolism*; D019590:Nucleocapsid Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016337:RNA, Catalytic / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012367:RNA, Viral / Q000378:metabolism*; D014779:Virus Replication / Q000502:physiology*
chemical_list: D000086462:Coronavirus Nucleocapsid Proteins; D018832:Molecular Chaperones; D019590:Nucleocapsid Proteins; D016337:RNA, Catalytic; D012367:RNA, Viral; D018833:Chaperonins