Analysis of global gene expression profiles of hPAF1 deficient A549 cells during stimulation with PR8/∆NS1 influenza virus, IFNβ1 or Poly(I:C)

Viral infection is commonly associated with virus-driven hijacking of host proteins. We describe a novel mechanism by which influenza virus impacts host cells through the interaction of influenza NS1 protein with the infected cell epigenome. We show that the NS1 protein of influenza A H3N2 targets the transcription elongation PAF1 complex (hPAF1C). We demonstrate that binding of NS1 to hPAF1C results in suppression of hPAF1C-mediated transcriptional elongation. More importantly,in the following data sets, we show that hPAF1 plays a crucial role in the antiviral response. Loss of hPAF1C reduces antiviral gene expression and reduces inducible transcription of target genes after stimulation with viral RNA analogue poly(I:C), vesicular stomatitis virus (VSV), exogenous recombinant IFN(beta) and influenza virus (H1N1). This study underscores the importance of hPAF1C in controlling inducible antiviral gene expression. Untreated (no siRNA), control siRNA-treated and hPAF1 siRNA-treated A549 cells were stimulated with PR8/∆NS1 influenza virus (MOI 1), IFNβ1 (500U/mL) or Poly(I:C) (2ug/mL). Total RNA was isolated with the Qiagen RNeasy mini kit. 200ng of total RNA per sample was used to prepare biotin-labeled RNA using MessageAmp™ Premier RNA Amplification Kit (Applied Biosystems) and hybridized to HumanHT-12 v4 Expression BeadChips (Illumina). Data analysis was performed using the GeneSpring GX11.0 software (Agilent Technologies). 3 biological replicates per condition