title: Toscana virus induces interferon although its NSs protein reveals antagonistic activity.
abstract: Toscana virus (TOSV) is a phlebotomus-transmitted virus that belongs to the family Bunyaviridae and causes widespread infections in humans; about 30 % of these cases result in aseptic meningitis. In the present study, it was shown that TOSV is an inducer of beta interferon (IFN-β), although its non-structural protein (NSs) could inhibit the induction of IFN-β if expressed in a heterologous context. A recombinant Rift Valley fever virus expressing the TOSV NSs could suppress IFN-β expression in infected cells. Moreover, in cells expressing NSs protein from a cDNA plasmid, IFN-β transcripts were not inducible by poly(I : C). Unlike other members of the family Bunyaviridae, TOSV appears to express an NSs protein that is a weak antagonist of IFN induction. Characterization of the interaction of TOSV with the IFN system will help our understanding of virus-host cell interactions and may explain why the pathogenesis of this disease is mostly mild in humans.
authors.affiliation: Department of Molecular Biology, Microbiology Section, University of Siena, 53100 Siena, Italy.
authors.forename: Gianni
authors.initials: G
authors.lastname: Gori Savellini
authors.forename: Friedemann
authors.initials: F
authors.lastname: Weber
authors.forename: Chiara
authors.initials: C
authors.lastname: Terrosi
authors.forename: Matthias
authors.initials: M
authors.lastname: Habjan
authors.forename: Barbara
authors.initials: B
authors.lastname: Martorelli
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Cusi
mesh_terms: D000818:Animals; D002460:Cell Line; D005822:Genetic Vectors; D006801:Humans; D016899:Interferon-beta / Q000037:antagonists & inhibitors* / Q000096:biosynthesis*; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D012296:Rift Valley fever virus / Q000235:genetics; D029301:Sandfly fever Naples virus / Q000276:immunology*; D017361:Viral Nonstructural Proteins / Q000235:genetics / Q000276:immunology*
chemical_list: D011994:Recombinant Proteins; D017361:Viral Nonstructural Proteins; D016899:Interferon-beta