title: The R35 residue of the influenza A virus NS1 protein has minimal effects on nuclear localization but alters virus replication through disrupting protein dimerization.
abstract: The influenza A virus NS1 protein has a nuclear localization sequence (NLS) in the amino terminal region. This NLS overlaps sequences that are important for RNA binding as well as protein dimerization. To assess the significance of the NS1 NLS on influenza virus replication, the NLS amino acids were individually mutated to alanines and recombinant viruses encoding these mutations were rescued. Viruses containing NS1 proteins with mutations at R37, R38 and K41 displayed minimal changes in replication or NS1 protein nuclear localization. Recombinant viruses encoding NS1 R35A were not recovered but viruses containing second site mutations at position D39 in addition to the R35A mutation were isolated. The mutations at position 39 were shown to partially restore NS1 protein dimerization but had minimal effects on nuclear localization. These data indicate that the amino acids in the NS1 NLS region play a more important role in protein dimerization compared to nuclear localization.
authors.affiliation: W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University, Bloomberg School of Public Health, 615 North Wolfe Street, Suite E5132, Baltimore, MD 21205-2103, USA.
authors.forename: Erin N
authors.initials: EN
authors.lastname: Lalime
authors.affiliation: W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University, Bloomberg School of Public Health, 615 North Wolfe Street, Suite E5132, Baltimore, MD 21205-2103, USA. Electronic address: apekosz@jhsph.edu.
authors.forename: Andrew
authors.initials: A
authors.lastname: Pekosz
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D002460:Cell Line; D004285:Dogs; D015967:Gene Expression Regulation, Viral / Q000502:physiology; D006801:Humans; D009980:Influenza A virus / Q000235:genetics / Q000378:metabolism*; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D019913:Nuclear Localization Signals / Q000502:physiology; D055503:Protein Multimerization; D021381:Protein Transport / Q000502:physiology*; D017361:Viral Nonstructural Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014779:Virus Replication / Q000502:physiology*
chemical_list: C085820:INS1 protein, influenza virus; D019913:Nuclear Localization Signals; D017361:Viral Nonstructural Proteins
keywords: Dimer; Influenza; NS1; Nuclear localization; RNA binding