title: Single-cell studies of IFN-β promoter activation by wild-type and NS1-defective influenza A viruses.
abstract: Deletion or truncation of NS1, the principal IFN antagonist of influenza viruses, leads to increased IFN induction during influenza virus infection. We have studied activation of the IFN induction cascade by both wild-type and NS1-defective viruses at the single-cell level using a cell line expressing GFP under the control of the IFN-β promoter and by examining MxA expression. The IFN-β promoter was not activated in all infected cells even during NS1-defective virus infections. Loss of NS1 expression is therefore insufficient per se to induce IFN in an infected cell, and factors besides NS1 expression status must dictate whether the IFN response is activated. The IFN response was efficiently stimulated in these cells following infection with other viruses; the differential IFN response we observe with influenza viruses is therefore not cell specific but is likely due to differences in the nature of the infecting virus particles and their subsequent replication.
authors.affiliation: Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK.|School of Biology, Biomedical Sciences Research Complex, North Haugh, University of St. Andrews, Fife KY16 9ST, UK.
authors.forename: M J
authors.initials: MJ
authors.lastname: Killip
authors.affiliation: School of Biology, Biomedical Sciences Research Complex, North Haugh, University of St. Andrews, Fife KY16 9ST, UK.
authors.forename: D
authors.initials: D
authors.lastname: Jackson
authors.affiliation: School of Biology, Biomedical Sciences Research Complex, North Haugh, University of St. Andrews, Fife KY16 9ST, UK.
authors.forename: M
authors.initials: M
authors.lastname: Pérez-Cidoncha
authors.affiliation: Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK.
authors.forename: E
authors.initials: E
authors.lastname: Fodor
authors.affiliation: School of Biology, Biomedical Sciences Research Complex, North Haugh, University of St. Andrews, Fife KY16 9ST, UK.
authors.forename: R E
authors.initials: RE
authors.lastname: Randall
mesh_terms: D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D009980:Influenza A virus / Q000235:genetics / Q000502:physiology*; D007251:Influenza, Human / Q000235:genetics / Q000276:immunology* / Q000821:virology*; D016899:Interferon-beta / Q000235:genetics*; D064547:Myxovirus Resistance Proteins / Q000235:genetics; D011401:Promoter Regions, Genetic; D059010:Single-Cell Analysis; D015533:Transcriptional Activation; D017361:Viral Nonstructural Proteins / Q000235:genetics / Q000378:metabolism*; D053586:Virus Internalization; D014779:Virus Replication
chemical_list: C085820:INS1 protein, influenza virus; C579071:MX1 protein, human; D064547:Myxovirus Resistance Proteins; D017361:Viral Nonstructural Proteins; D049452:Green Fluorescent Proteins; D016899:Interferon-beta