About the Seminar
Influenza A viruses (IAV) are major human respiratory pathogens that cause annual epidemics and occasional pandemics globally. IAV has evolved its viral proteins to interact with cellular proteins to aid in the regulation of viral replication and ultimately cause disease pathogenesis. More specifically, the ribonucleoprotein complexes (RNPs) interact with many host cell kinases that have been shown to regulate viral replication. These host cell kinases can interact with any one of the components of the ribonucleoprotein complexes: the viral genomic RNA segment, the viral polymerase (PA, PB1, PB2) or the viral nucleoprotein (NP). Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that has been shown to co-localize with NP in infected cells, and when FAK is inhibited viral RNA levels are low suggesting that FAK upregulates viral replication through NP interactions. However, how the specific interactions between FAK and NP contribute to disease is not well understood primarily due to the unknown nature of how FAK and NP associate together. Ultimately, there is a gap in the knowledge of whether or not 1) FAK directly interacts with NP alone or if FAK associates with NP through interactions with the viral genomic RNA or the viral polymerase proteins within the ribonucleoprotein complex, and 2) if FAK interacts with NP in a common region across all subtypes of NP found in IAV strains. Therefore, this proposal aims to define the interactions between FAK and viral NP. First, we will determine if FAK and NP directly interact through cross-linking/mass spectrometry. We will utilize multiple antibodies to isolate various FAK complexes generated from a formaldehyde cross-linking treatment in vitro. These complexes will be digested into small peptides in order to identify the cross-linked peptides via liquid chromatography electrospray ionization tandem mass spectrometry. Additionally, we will corroborate the specific interactions of FAK and NP determined from cross-linking/mass spectrometry through cryo electron microscopy. Furthermore, bioinformatic analysis will be utilized to identify common regions between NP subtypes that interact with FAK. By understanding how the ribonucleoprotein complexes interact with cellular kinases during replication, we can target specific virus-host interactions in the development of universal therapeutics for the treatment influenza A virus infection.