title: Mapping of the VP40-binding regions of the nucleoprotein of Ebola virus.
abstract: Expression of Ebola virus nucleoprotein (NP) in mammalian cells leads to the formation of helical structures, which serve as a scaffold for the nucleocapsid. We recently found that NP binding with the matrix protein VP40 is important for nucleocapsid incorporation into virions (T. Noda, H. Ebihara, Y. Muramoto, K. Fujii, A. Takada, H. Sagara, J. H. Kim, H. Kida, H. Feldmann, and Y. Kawaoka, PLoS Pathog. 2:e99, 2006). To identify the region(s) on the NP molecule required for VP40 binding, we examined the interaction of a series of NP deletion mutants with VP40 biochemically and ultrastructurally. We found that both termini of NP (amino acids 2 to 150 and 601 to 739) are essential for its interaction with VP40 and for its incorporation into virus-like particles (VLPs). We also found that the C terminus of NP is important for nucleocapsid incorporation into virions. Of interest is that the formation of NP helices, which involves the N-terminal 450 amino acids of NP, is dispensable for NP incorporation into VLPs. These findings enhance our understanding of Ebola virus assembly and in so doing move us closer to the identification of targets for the development of antiviral compounds to combat Ebola virus infection.
authors.affiliation: Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Drive, Madison, WI 53706, USA.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Noda
authors.forename: Shinji
authors.initials: S
authors.lastname: Watanabe
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sagara
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kawaoka
mesh_terms: D001665:Binding Sites; D036022:Capsid Proteins / Q000378:metabolism; D002460:Cell Line; D029043:Ebolavirus / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D046529:Microscopy, Electron, Transmission; D016253:Microscopy, Immunoelectron; D009154:Mutation / Q000235:genetics; D009698:Nucleoproteins / Q000235:genetics / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000378:metabolism; D011485:Protein Binding; D014763:Viral Matrix Proteins / Q000235:genetics / Q000378:metabolism*; D014771:Virion / Q000378:metabolism
chemical_list: D036022:Capsid Proteins; D009698:Nucleoproteins; C080981:VP40 protein, virus; D014763:Viral Matrix Proteins; D010447:Peptide Hydrolases