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SMARCA2-regulated host cell factors are required for MxA restriction of influenza A viruses.

ABSTRACT: The human interferon (IFN)-induced MxA protein is a key antiviral host restriction factor exhibiting broad antiviral activity against many RNA viruses, including highly pathogenic avian influenza A viruses (IAV) of the H5N1 and H7N7 subtype. To date the mechanism for how MxA exerts its antiviral activity is unclear, however, additional cellular factors are believed to be essential for this activity. To identify MxA cofactors we performed a genome-wide siRNA-based screen in human airway epithelial cells (A549) constitutively expressing MxA using an H5N1 reporter virus. These data were complemented with a proteomic screen to identify MxA-interacting proteins. The combined data identified SMARCA2, the ATPase subunit of the BAF chromatin remodeling complex, as a crucial factor required for the antiviral activity of MxA against IAV. Intriguingly, our data demonstrate that although SMARCA2 is essential for expression of some IFN-stimulated genes (ISGs), and the establishment of an antiviral state, it is not required for expression of MxA, suggesting an indirect effect on MxA activity. Transcriptome analysis of SMARCA2-depleted A549-MxA cells identified a small set of SMARCA2-regulated factors required for activity of MxA, in particular IFITM2 and IGFBP3. These findings reveal that several virus-inducible factors work in concert to enable MxA restriction of IAV.

SUBMITTER: Dornfeld D

PROVIDER: S-EPMC5794779 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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SMARCA2-regulated host cell factors are required for MxA restriction of influenza A viruses.

Dornfeld Dominik D Dudek Alexandra H AH Vausselin Thibaut T Günther Sira C SC Hultquist Judd F JF Giese Sebastian S Khokhlova-Cubberley Daria D Chew Yap C YC Pache Lars L Krogan Nevan J NJ Garcia-Sastre Adolfo A Schwemmle Martin M Shaw Megan L ML

Scientific reports 20180201 1

The human interferon (IFN)-induced MxA protein is a key antiviral host restriction factor exhibiting broad antiviral activity against many RNA viruses, including highly pathogenic avian influenza A viruses (IAV) of the H5N1 and H7N7 subtype. To date the mechanism for how MxA exerts its antiviral activity is unclear, however, additional cellular factors are believed to be essential for this activity. To identify MxA cofactors we performed a genome-wide siRNA-based screen in human airway epithelia ...[more]

PMID: 29391557

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Dataset Information

SMARCA2-regulated host cell factors are required for MxA restriction of influenza A viruses.

Publications

SMARCA2-regulated host cell factors are required for MxA restriction of influenza A viruses.

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