title: Critical role of Dengue Virus NS1 protein in viral replication.
abstract: Dengue virus (DENV) nonstructural protein 1 (NS1) is a highly conserved 46-kDa protein that contains 2 glycosylation sites (Asn-130 and Asn-207) and 12 conserved cysteine (Cys) residues. Here, we performed site-directed mutagenesis to generate systematic mutants of viral strain TSV01. The results of the subsequent analysis showed that an alanine substitution at the second N-linked glycan Asn-207 in NS1 delayed viral RNA synthesis, reduced virus plaque size, and weakened the cytopathic effect. Three mutants at Cys sites (Cys-4, Cys-55, Cys-291) and a C-terminal deletion (ΔC) mutant significantly impaired RNA synthesis, and consequently abolished viral growth, whereas alanine mutations at Asn-130 and Glu-173 resulted in phenotypes that were similar to the wild-type (WT) virus. Further analysis showed that the Asn-207 mutation slightly delayed viral replication. These results suggest that the three conserved disulfide bonds and the second N-linked glycan in NS1 are required for DENV-2 replication.
authors.affiliation: Key Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Fan
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Yuan
mesh_terms: D003716:Dengue Virus / Q000235:genetics* / Q000502:physiology*; D016297:Mutagenesis, Site-Directed; D017361:Viral Nonstructural Proteins / Q000235:genetics / Q000378:metabolism*; D014779:Virus Replication / Q000235:genetics* / Q000502:physiology
chemical_list: D017361:Viral Nonstructural Proteins