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bioRxiv · 10.1101/2021.04.23.441102

Amino acid residues involved in inhibition of host gene expression by influenza A/Brevig Mission/1/1918 PA-X

Chiem, K.·Martinez-Sobrido, L.·Nogales, A.·DeDiego, M. L.
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Abstract

Influenza A virus (IAV) PA-X protein is a virulence factor that selectively degrades host mRNAs leading to protein shutoff. This function modulates host inflammation, antiviral responses, cell apoptosis, and pathogenesis. In this work we describe a novel approach based on the use of bacteria and a plasmid encoding the PA-X gene under the control of the bacteriophage T7 promoter to identify amino acid residues important for A/Brevig Mission/1/1918 H1N1 PA-Xs shutoff activity. Using this system, we have identified PA-X mutants encoding single or double amino acid changes, which diminish its host shutoff activity, as well as its ability to counteract interferon responses upon viral infection. This novel bacteria-based approach could be used for the identification of viral proteins that inhibit host gene expression as well as the amino acid residues responsible for inhibition of host gene expression.

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Chiem, K., Martinez-Sobrido, L., Nogales, A., DeDiego, M. L.. 2021-04-23. Amino acid residues involved in inhibition of host gene expression by influenza A/Brevig Mission/1/1918 PA-X. https://doi.org/10.1101/2021.04.23.441102

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