title: Modulation of the Host Lipid Landscape to Promote RNA Virus Replication: The Picornavirus Encephalomyocarditis Virus Converges on the Pathway Used by Hepatitis C Virus.
abstract: Cardioviruses, including encephalomyocarditis virus (EMCV) and the human Saffold virus, are small non-enveloped viruses belonging to the Picornaviridae, a large family of positive-sense RNA [(+)RNA] viruses. All (+)RNA viruses remodel intracellular membranes into unique structures for viral genome replication. Accumulating evidence suggests that picornaviruses from different genera use different strategies to generate viral replication organelles (ROs). For instance, enteroviruses (e.g. poliovirus, coxsackievirus, rhinovirus) rely on the Golgi-localized phosphatidylinositol 4-kinase III beta (PI4KB), while cardioviruses replicate independently of the kinase. By which mechanisms cardioviruses develop their ROs is currently unknown. Here we show that cardioviruses manipulate another PI4K, namely the ER-localized phosphatidylinositol 4-kinase III alpha (PI4KA), to generate PI4P-enriched ROs. By siRNA-mediated knockdown and pharmacological inhibition, we demonstrate that PI4KA is an essential host factor for EMCV genome replication. We reveal that the EMCV nonstructural protein 3A interacts with and is responsible for PI4KA recruitment to viral ROs. The ensuing phosphatidylinositol 4-phosphate (PI4P) proved important for the recruitment of oxysterol-binding protein (OSBP), which delivers cholesterol to EMCV ROs in a PI4P-dependent manner. PI4P lipids and cholesterol are shown to be required for the global organization of the ROs and for viral genome replication. Consistently, inhibition of OSBP expression or function efficiently blocked EMCV RNA replication. In conclusion, we describe for the first time a cellular pathway involved in the biogenesis of cardiovirus ROs. Remarkably, the same pathway was reported to promote formation of the replication sites of hepatitis C virus, a member of the Flaviviridae family, but not other picornaviruses or flaviviruses. Thus, our results highlight the convergent recruitment by distantly related (+)RNA viruses of a host lipid-modifying pathway underlying formation of viral replication sites.
authors.affiliation: Department of Infectious Diseases & Immunology, Virology Division, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Cristina M
authors.initials: CM
authors.lastname: Dorobantu
authors.affiliation: Department of Infectious Diseases & Immunology, Virology Division, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Lucian
authors.initials: L
authors.lastname: Albulescu
authors.affiliation: Department of Infectious Diseases, Molecular Virology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Harak
authors.affiliation: Department of Infectious Diseases & Immunology, Virology Division, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Qian
authors.initials: Q
authors.lastname: Feng
authors.affiliation: Department of Infectious Diseases & Immunology, Virology Division, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Mirjam
authors.initials: M
authors.lastname: van Kampen
authors.affiliation: Department of Infectious Diseases & Immunology, Virology Division, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Jeroen R P M
authors.initials: JR
authors.lastname: Strating
authors.affiliation: Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands; Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia.
authors.forename: Alexander E
authors.initials: AE
authors.lastname: Gorbalenya
authors.affiliation: Department of Infectious Diseases, Molecular Virology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Volker
authors.initials: V
authors.lastname: Lohmann
authors.affiliation: Department of Infectious Diseases & Immunology, Virology Division, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Hilde M
authors.initials: HM
authors.lastname: van der Schaar
authors.affiliation: Department of Infectious Diseases & Immunology, Virology Division, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Frank J M
authors.initials: FJ
authors.lastname: van Kuppeveld
mesh_terms: D019870:1-Phosphatidylinositol 4-Kinase / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D018188:Cardiovirus Infections / Q000378:metabolism*; D004686:Encephalomyocarditis virus / Q000502:physiology*; D016174:Hepacivirus / Q000502:physiology; D006790:Host-Parasite Interactions / Q000502:physiology*; D006801:Humans; D047468:Immunoprecipitation; D050356:Lipid Metabolism / Q000502:physiology*; D008856:Microscopy, Fluorescence; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism; D010849:Picornaviridae; D012328:RNA Viruses; D034741:RNA, Small Interfering; D011987:Receptors, Steroid / Q000378:metabolism; D014162:Transfection; D014779:Virus Replication / Q000502:physiology*; D000098825:Oxysterol Binding Proteins
chemical_list: D018129:Phosphatidylinositol Phosphates; D034741:RNA, Small Interfering; D011987:Receptors, Steroid; D000098825:Oxysterol Binding Proteins; C037178:phosphatidylinositol 4-phosphate; D019870:1-Phosphatidylinositol 4-Kinase