title: Identification and characterization of the RNA helicase activity of Japanese encephalitis virus NS3 protein.
abstract: The NS3 protein of Japanese encephalitis virus (JEV) contains motifs typical of RNA helicase/NTPase but no RNA helicase activity has been reported for this protein. To identify and characterize the RNA helicase activity of JEV NS3, a truncated form of the protein with a His-tag was expressed in Escherichia coli and purified. The purified JEV NS3 protein showed an RNA helicase activity, which was dependent on divalent cations and ATP. An Asp-285-to-Ala substitution in motif II of the JEV NS3 protein abolished the ATPase and RNA helicase activities. These results indicate that the C-terminal 457 residues are sufficient to exhibit the RNA helicase activity of JEV NS3.
authors.affiliation: Department of Bioprocessing, Faculty of Agriculture, Gifu University, 1-1 Yanagido, Gifu, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Utama
authors.forename: H
authors.initials: H
authors.lastname: Shimizu
authors.forename: S
authors.initials: S
authors.lastname: Morikawa
authors.forename: F
authors.initials: F
authors.lastname: Hasebe
authors.forename: K
authors.initials: K
authors.lastname: Morita
authors.forename: A
authors.initials: A
authors.lastname: Igarashi
authors.forename: M
authors.initials: M
authors.lastname: Hatsu
authors.forename: K
authors.initials: K
authors.lastname: Takamizawa
authors.forename: T
authors.initials: T
authors.lastname: Miyamura
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry; D004926:Escherichia coli / Q000378:metabolism; D015870:Gene Expression; D016297:Mutagenesis, Site-Directed; D020365:RNA Helicases / Q000737:chemistry*; D012697:Serine Endopeptidases; D013379:Substrate Specificity; D017361:Viral Nonstructural Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases
chemical_list: D000251:Adenosine Triphosphatases; D020365:RNA Helicases; D012697:Serine Endopeptidases; D017361:Viral Nonstructural Proteins; C060028:NS3 protein, flavivirus; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases