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bioRxiv · 10.1101/2020.08.17.254060

Old Dog, New Tricks: Influenza A Virus NS1 and In Vitro Fibrillogenesis

Shaldzhyan, A.·Zabrodskaya, Y.·Baranovskaya, I.·Sergeeva, M.·Gorshkov, A.·Savin, I.·Shishlyannikov, S.·Ramsay, E.·Protasov, A.·Kukhareva, A.·Egorov, V.
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Abstract

The influenza NS1 protein is involved in suppression of the host immune response. Recently, there is growing evidence that prion-like protein aggregation plays an important role in cellular signaling and immune responses. In this work, we obtained a recombinant, influenza A NS1 protein and showed that it is able to form amyloid-like fibrils in vitro. Using proteolysis and subsequent mass spectrometry, we showed that regions resistant to protease hydrolysis highly differ between the native NS1 form (NS1-N) and fibrillar form (NS1-F); this indicates that significant structural changes occur during fibril formation. The discovery of the ability of NS1 to form amyloid-like fibrils may be relevant to uncovering relationships between influenza A infection and modulation of the immune response.

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Shaldzhyan, A., Zabrodskaya, Y., Baranovskaya, I., Sergeeva, M., Gorshkov, A., Savin, I., Shishlyannikov, S., Ramsay, E., Protasov, A., Kukhareva, A., Egorov, V.. 2020-08-17. Old Dog, New Tricks: Influenza A Virus NS1 and In Vitro Fibrillogenesis. https://doi.org/10.1101/2020.08.17.254060

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