Trends in Microbiology
ReviewImmunomodulatory Nonstructural Proteins of Influenza A Viruses
Section snippets
Influenza Viruses
Influenza viruses cause respiratory infections that affect millions of people annually and result in an estimated 250 000–500 000 deaths worldwidei. The family Orthomyxoviridae includes, among others, influenza viruses A, B, and C. Here, we focus on influenza A viruses (IAVs), which have the greatest impact on public health and have been extensively studied.
IAVs are enveloped viruses with a genome consisting of eight negative-sense RNA segments (reviewed in [1]). The genome encodes nine
Viral Immune-Modulatory Proteins
In addition to structural proteins, the genome of the IAV encodes nonstructural proteins that influence viral replication and the host response (Table 1) (reviewed in [2]). Among the nonstructural proteins, PB1-F2 and PA-X are a result of the translation of alternative open reading frames (ORFs) after ribosomal frameshifting, while NS1 is the product of a nonspliced mRNA of genome segment 8 (reviewed in [14]). To date, NS1 is the best-studied virulence factor of IAV; however, PB1-F2 and PA-X
Concluding Remarks
The growing lists of binding partners of IAV proteins reveal a complex dynamic network between the virus and its host. We are beginning to understand how IAVs enable efficient progeny virus production by the host cell, which goes far beyond a simple inhibition of the antiviral host response. Nonstructural proteins, like NS1, PB1-F2, and PA-X, execute many of these host modulations. Thereby, the activity of these multifunctional proteins must be temporally and spatially regulated, which will
Acknowledgments
We would like to thank Dr Eike R. Hrincius (Institute of Virology, WWU, Muenster, Germany) for critical reading of this manuscript and fruitful discussion. This work was supported by the Interdisciplinary Centre of Clinical Research of the Muenster Medical School (IZKF Lud2/008/17 and EhC2/006/15) and the German Research Foundation (SFB1009/B02).
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2021, Computers in Biology and MedicineCitation Excerpt :These studies mainly target only essential virus protein components such as non-structural proteins, glycoproteins, and receptor binding proteins for designing epitope-based subunit vaccine candidates, as these proteins are integral components for virus pathogenesis [26]. But components other than non-structural proteins can also potentially act as immunogens [27,28]. Thus, this study included essential protein components and all other virus components to identify epitope-based subunit vaccine candidates against lung cancer-causing viruses.
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