title: RNA helicase retinoic acid-inducible gene I as a sensor of Hantaan virus replication.
abstract: Hantaan virus (HTNV) causes severe human disease. The HTNV genome consists of three ssRNA segments of negative polarity that are complexed with viral nucleocapsid (N) protein. How the human innate immune system detects HTNV is unclear. RNA helicase retinoic acid-inducible gene I (RIG-I) does not sense genomic HTNV RNA. So far it has not been analysed whether pathogen-associated molecular patterns generated during the HTNV replication trigger RIG-I-mediated innate responses. Indeed, we found that knock-down of RIG-I in A549 cells, an alveolar epithelial cell line, increases HTNV replication and prevents induction of 2',5'-oligoadenylate synthetase, an interferon-stimulated gene. Moreover, overexpression of wild-type or constitutive active RIG-I in Huh7.5 cells lacking a functional RIG-I diminished HTNV virion production. Intriguingly, reporter assays revealed that in vitro-transcribed HTNV N RNA and expression of the HTNV N ORF triggers RIG-I signalling. This effect was completely blocked by the RNA-binding domain of vaccinia virus E3 protein, suggesting that dsRNA-like secondary structures of HTNV N RNA stimulate RIG-I. Finally, transfection of HTNV N RNA into A549 cells resulted in a 2 log-reduction of viral titres upon challenge with virus. Our study is the first demonstration that RIG-I mediates antiviral innate responses induced by HTNV N RNA during HTNV replication and interferes with HTNV growth.
authors.affiliation: Institute of Medical Virology, Charité - Universitätsmedizin Berlin, D-10098 Berlin, Germany.
authors.forename: Min-Hi
authors.initials: MH
authors.lastname: Lee
authors.affiliation: Institute of Medical Virology, Charité - Universitätsmedizin Berlin, D-10098 Berlin, Germany.
authors.forename: Pritesh
authors.initials: P
authors.lastname: Lalwani
authors.affiliation: Institute of Medical Virology, Charité - Universitätsmedizin Berlin, D-10098 Berlin, Germany.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Raftery
authors.affiliation: Robert Koch Institute, D-13302 Berlin, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Matthaei
authors.affiliation: Institute of Medical Virology, Charité - Universitätsmedizin Berlin, D-10098 Berlin, Germany.
authors.forename: Nina
authors.initials: N
authors.lastname: Lütteke
authors.affiliation: Institute of Medical Virology, Charité - Universitätsmedizin Berlin, D-10098 Berlin, Germany.
authors.forename: Sina
authors.initials: S
authors.lastname: Kirsanovs
authors.affiliation: Department of Molecular Virology, University of Heidelberg, D-69120 Heidelberg, Germany.
authors.forename: Marco
authors.initials: M
authors.lastname: Binder
authors.affiliation: Friedrich Loeffler Institute, Institute for Novel and Emerging Infectious Diseases, D-17493 Greifswald-Insel Riems, Germany.
authors.forename: Rainer G
authors.initials: RG
authors.lastname: Ulrich
authors.affiliation: Institute of Immunology, University of Heidelberg, D-69120 Heidelberg, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Giese
authors.affiliation: Robert Koch Institute, D-13302 Berlin, Germany.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Wolff
authors.affiliation: Institute of Medical Virology, Charité - Universitätsmedizin Berlin, D-10098 Berlin, Germany.
authors.forename: Detlev H
authors.initials: DH
authors.lastname: Krüger
authors.affiliation: Institute of Medical Virology, Charité - Universitätsmedizin Berlin, D-10098 Berlin, Germany.
authors.forename: Günther
authors.initials: G
authors.lastname: Schönrich
mesh_terms: D002460:Cell Line; D000071457:DEAD Box Protein 58; D053487:DEAD-box RNA Helicases / Q000276:immunology / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D018063:Hantaan virus / Q000276:immunology / Q000502:physiology*; D054884:Host-Pathogen Interactions; D006801:Humans; D011971:Receptors, Immunologic; D014779:Virus Replication
chemical_list: D011971:Receptors, Immunologic; C452820:RIGI protein, human; D000071457:DEAD Box Protein 58; D053487:DEAD-box RNA Helicases