Stabilization of p53 in Influenza A Virus-infected Cells Is Associated with Compromised MDM2-mediated Ubiquitination of p53

In mammals the interferon (IFN) system is a central innate antiviral defence mechanism, while the involvement of RNA interference (RNAi) in antiviral response against RNA viruses is uncertain. Here, we tested whether RNAi is involved in the antiviral response in mammalian cells. To investigate the role of RNAi in influenza A virus-infected cells in the absence of IFN, we used Vero cells that lack IFN-α and IFN-β genes. Our results demonstrate that knockdown of a key RNAi component, Dicer, led to a modest increase of virus production and accelerated apoptosis of influenza A virus-infected cells. These effects were much weaker in the presence of IFN. The results also show that in both Vero cells and the IFN-producing alveolar epithelial A549 cell line influenza A virus targets Dicer at mRNA and protein levels. Thus, RNAi is involved in antiviral response, and Dicer is important for protection against influenza A virus infection.

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Influenza A Virus Replication Induces Cell Cycle Arrest in G0/G1 Phase

Journal of Virology ◽

10.1128/jvi.01216-10 ◽

2010 ◽

Vol 84 (24) ◽

pp. 12832-12840 ◽

Cited By ~ 85

Author(s):

Yuan He ◽

Ke Xu ◽

Bjoern Keiner ◽

Jianfang Zhou ◽

Volker Czudai ◽

...

Keyword(s):

Cell Cycle ◽

Cell Cycle Arrest ◽

Influenza A Virus ◽

Influenza A ◽

Cell Cycle Progression ◽

Virus Production ◽

Phase Cell ◽

Cycle Progression ◽

Cycle Arrest ◽

Infected Cells

ABSTRACT Many viruses interact with the host cell division cycle to favor their own growth. In this study, we examined the ability of influenza A virus to manipulate cell cycle progression. Our results show that influenza A virus A/WSN/33 (H1N1) replication results in G0/G1-phase accumulation of infected cells and that this accumulation is caused by the prevention of cell cycle entry from G0/G1 phase into S phase. Consistent with the G0/G1-phase accumulation, the amount of hyperphosphorylated retinoblastoma protein, a necessary active form for cell cycle progression through late G1 into S phase, decreased after infection with A/WSN/33 (H1N1) virus. In addition, other key molecules in the regulation of the cell cycle, such as p21, cyclin E, and cyclin D1, were also changed and showed a pattern of G0/G1-phase cell cycle arrest. It is interesting that increased viral protein expression and progeny virus production in cells synchronized in the G0/G1 phase were observed compared to those in either unsynchronized cells or cells synchronized in the G2/M phase. G0/G1-phase cell cycle arrest is likely a common strategy, since the effect was also observed in other strains, such as H3N2, H9N2, PR8 H1N1, and pandemic swine H1N1 viruses. These findings, in all, suggest that influenza A virus may provide favorable conditions for viral protein accumulation and virus production by inducing a G0/G1-phase cell cycle arrest in infected cells.

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Type I IFN Triggers RIG-I/TLR3/NLRP3-dependent Inflammasome Activation in Influenza A Virus Infected Cells

PLoS Pathogens ◽

10.1371/journal.ppat.1003256 ◽

2013 ◽

Vol 9 (4) ◽

pp. e1003256 ◽

Cited By ~ 124

Author(s):

Julien Pothlichet ◽

Isabelle Meunier ◽

Beckley K. Davis ◽

Jenny P-Y. Ting ◽

Emil Skamene ◽

...

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

Inflammasome Activation ◽

Type I ◽

Type I Ifn ◽

Infected Cells

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Amphotericin b effect on the sensitivity to influenza infection of WI-38 VA-13 cells with IFITM3 gene knockout

Medical academic journal ◽

10.17816/maj76106 ◽

2021 ◽

Vol 21 (3) ◽

pp. 109-112

Author(s):

Kira S. Koryabina ◽

Mariya V. Sergeeva ◽

Andrey B. Komissarov ◽

Nataliya V. Eshchenko ◽

Grigoriy A. Stepanov

Keyword(s):

Amphotericin B ◽

Influenza A Virus ◽

Influenza A ◽

Gene Knockout ◽

Influenza Infection ◽

Restriction Factors ◽

Host Restriction ◽

Host Restriction Factors ◽

Infected Cells ◽

The Difference

BACKGROUND: The application of CRISPR/Cas9 is one of the most rapidly developing areas in biotechnology. This method was used to obtain clones of а human origin cell line with knockout of one or more genes of the IFITM family, representing host restriction factors for influenza infection. Amphotericin B has previously been shown to promote influenza infection by blocking IFITM3 function. AIM: The aim of this study was to evaluate the effect of amphotericin B on the sensitivity of IFITM knockout cells to influenza A virus infection. MATERIALS AND METHODS: WI-38 VA-13 cells and mutant clones with IFITM3 knockout (F3 clone) or IFITM1, IFITM3 knockout (clone E12) were infected with influenza virus A/PR/8/34 (H1N1) in the presence or absence of amphotericin B. Forty-four hours after infection, the culture medium was taken to determine the infectious activity of the virus by titration in the MDCK cell culture, as well as the hemagglutinating activity of the virus. The infected cells were stained with fluorescently labeled antibodies against the viral NP protein, and the number of NP-positive cells was determined by flow cytometry. RESULTS: The addition of amphotericin B increased the hemagglutinating and infectious activity of the virus in WI-38 VA-13cells, while the difference was insignificant for clones with IFITM gene knockout. A similar dependency was obtained for the percent of infected cells. CONCLUSIONS: Mutant cells with a knockout of one or several genes of the IFITM family were equally susceptible to influenza infection regardless of the addition of amphotericin B, which confirms the crucial importance of a defect in the IFITM3 protein in increasing the permissiveness of cells to influenza A virus.

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Influenza type A virus M protein expression on infected cells is responsible for cross-reactive recognition by cytotoxic thymus-derived lymphocytes

Infection and Immunity ◽

10.1128/iai.29.2.719-723.1980 ◽

1980 ◽

Vol 29 (2) ◽

pp. 719-723 ◽

Cited By ~ 1

Author(s):

C S Reiss ◽

J L Schulman

Keyword(s):

T Cell ◽

Influenza A Virus ◽

Influenza A ◽

Rabbit Antiserum ◽

Type A ◽

M Protein ◽

Cytotoxic T Cell ◽

Influenza A Viruses ◽

Infected Cells ◽

Cytotoxic T Cell Responses

M protein of influenza A virus was detected with rabbit antiserum by both indirect immunofluorescence and by antibody plus complement-mediated cytolysis on the cell surfaces of both productively and nonproductively infected cells. In contrast, antiserum to nucleoprotein failed to react with unfixed infected cells, but did bind to fixed infected cells, especially in the perinuclear area. Incorporation of antiserum to M protein in a T-cell-mediated cytotoxicity assay produced almost complete abrogation of lysis of H-2-compatible cells infected with an influenza A virus of a subtype which differed from that used to elicit the cytotoxic T cells. However, the antibody did not significantly block 51Cr release from cells infected with the homotypic type A influenza virus. These observations are in accord with the hypothesis that the cross-reactive cytotoxic T-cell responses seen with cells infected by heterotypic influenza A viruses are due to recognition of a common M protein.

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Time-Resolved Visualisation of Nearly-Native Influenza A Virus Progeny Ribonucleoproteins and Their Individual Components in Live Infected Cells

PLoS ONE ◽

10.1371/journal.pone.0149986 ◽

2016 ◽

Vol 11 (3) ◽

pp. e0149986 ◽

Cited By ~ 9

Author(s):

Sergiy Avilov ◽

Julie Magnus ◽

Stephen Cusack ◽

Nadia Naffakh

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

Time Resolved ◽

Virus Progeny ◽

Infected Cells

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Complement-Dependent Lysis of Influenza A Virus-Infected Cells by Broadly Cross-Reactive Human Monoclonal Antibodies

Journal of Virology ◽

10.1128/jvi.05193-11 ◽

2011 ◽

Vol 85 (24) ◽

pp. 13463-13467 ◽

Cited By ~ 66

Author(s):

M. Terajima ◽

J. Cruz ◽

M. D. T. Co ◽

J.-H. Lee ◽

K. Kaur ◽

...

Keyword(s):

Monoclonal Antibodies ◽

Influenza A Virus ◽

Influenza A ◽

Human Monoclonal Antibodies ◽

Infected Cells

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The NS1 Protein of Influenza A Virus Blocks RIG-I-Mediated Activation of the Noncanonical NF-κB Pathway and p52/RelB-Dependent Gene Expression in Lung Epithelial Cells

Journal of Virology ◽

10.1128/jvi.00323-12 ◽

2012 ◽

Vol 86 (18) ◽

pp. 10211-10217 ◽

Cited By ~ 43

Author(s):

Andrea Rückle ◽

Emanuel Haasbach ◽

Ilkka Julkunen ◽

Oliver Planz ◽

Christina Ehrhardt ◽

...

Keyword(s):

Gene Expression ◽

Epithelial Cells ◽

Influenza A Virus ◽

Influenza A ◽

Target Gene ◽

Lung Epithelial Cells ◽

Ns1 Protein ◽

Antiviral Immune Response ◽

Lung Epithelial ◽

Infected Cells

Influenza A virus (IAV) infection of epithelial cells activates NF-κB transcription factors via the canonical NF-κB signaling pathway, which modulates both the antiviral immune response and viral replication. Since almost nothing is known so far about a function of noncanonical NF-κB signaling after IAV infection, we tested infected cells for activation of p52 and RelB. We show that the viral NS1 protein strongly inhibits RIG-I-mediated noncanonical NF-κB activation and expression of the noncanonical target gene CCL19.

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Regulation of Influenza A Virus Nucleoprotein Oligomerization by Phosphorylation

Journal of Virology ◽

10.1128/jvi.02332-14 ◽

2014 ◽

Vol 89 (2) ◽

pp. 1452-1455 ◽

Cited By ~ 26

Author(s):

Lauren Turrell ◽

Edward C. Hutchinson ◽

Frank T. Vreede ◽

Ervin Fodor

Keyword(s):

Influenza Virus ◽

Influenza A Virus ◽

Influenza A ◽

Serine Residue ◽

Reversible Phosphorylation ◽

Viral Growth ◽

Ribonucleoprotein Complex ◽

Infected Cells ◽

Neighboring Molecule

In the influenza virus ribonucleoprotein complex, the oligomerization of the nucleoprotein is mediated by an interaction between the tail-loop of one molecule and the groove of the neighboring molecule. In this study, we show that phosphorylation of a serine residue (S165) within the groove of influenza A virus nucleoprotein inhibits oligomerization and, consequently, ribonucleoprotein activity and viral growth. We propose that nucleoprotein oligomerization in infected cells is regulated by reversible phosphorylation.

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