Targeting Viral Proteostasis Limits Influenza Virus, HIV, and Dengue Virus Infection

Abstract

Viruses are obligate parasites as they require the machinery of the host cell to replicate. Inhibition of host factors co-opted during active infection is a strategy to suppress viral replication and a potential pan antiviral therapy. To define the cellular proteins and processes required for a virus during infection is thus crucial to understanding the mechanisms of virally induced disease. In this report, we generated fully infectious tagged influenza viruses and used infection-based proteomics to identify pivotal arms of cellular signaling required for influenza virus growth and infectivity. Using mathematical modeling, genetic, and pharmacologic approaches, we revealed that modulation of Sec61-mediated cotranslational translocation selectively impaired glycoprotein proteostasis of influenza as well as HIV and dengue viruses, and led to inhibition of viral growth and infectivity. Thus, by studying virus-human protein-protein interactions in the context of active replication we have identified targetable host factors for broad-spectrum antiviral therapies.

The RNA Exosome Syncs IAV-RNAPII Transcription to Promote Viral Ribogenesis and Infectivity

“…Global maps of host-virus protein-protein interactions have been instrumental for identifying binary and complex interactions for validation in more physiological systems (Heaton et al, 2016; Pichlmair et al, 2012; Rozenblatt-Rosen et al, 2012; Shapira et al, 2009). To discover key regulators of IAV biogenesis we mapped the global interaction network of each viral polymerase subunit in A549 cells (Figure S1 and Table S1).…”

“…To do so, we analyzed the interaction network of FLAG-PA, FLAG-PB2, and FLAG-PB1 H1N1 viruses in infected A549 cells (Heaton et al, 2016). These viruses bear genomic insertions in the 5’ proximal region of their respective segments that encode for a FLAG epitope.…”

“…These viruses bear genomic insertions in the 5’ proximal region of their respective segments that encode for a FLAG epitope. These configurations allow the expression of viral proteins to be regulated by the viral life cycle and permit formation of functional viral polymerase complexes (Heaton, et al 2016). This approach yielded two lines of evidence that support a direct, physical interaction between the viral polymerase complex and the nuclear RNA exosome.…”

“…The influenza virus A/PR/8/34 (H1N1 subtype), FLAG-tagged A/PR/8/34 viruses, and luciferase-expressing A/PR8/8/34 virus were propagated in 10-day old specific pathogen-free chicken eggs (Heaton et al, 2013; Heaton et al, 2016) For the later virus, luciferase expression was monitored using Promega’s renilla assay system (E2810). This assay was also used to monitor luciferase expression for HSV-1-Luc (Summers and Leib 2002).…”

Proteomics Tracing the Footsteps of Infectious Disease

“…Moreover, global proteomic approaches that employ DDA inherently lack a pathway bias, because specific cellular pathways are not targeted. In a notable example, this approach allowed the identification of a host pathway, Sec61-mediated cotranslational translocation, that when disrupted, was broadly inhibitory to influenza, HIV, and dengue virus growth and infectivity (58). Another example of expertly leveraging global whole cell proteomics and in-solution protein isoelectric focusing was a study from Dave and colleagues, in which the epithelial host cell response to human respiratory syncytial virus (hRSV) infection was investigated (59).…”