RESEARCH ARTICLE Hepatitis C Virus Frameshift/Alternate Reading Frame Protein Suppresses Interferon Responses Mediated by Pattern Recognition Receptor Retinoic-Acid-Inducible Gene-I Seung Bum Park1, Scott Seronello1, Wasima Mayer1, David M. Ojcius1,2* 1 School of Natural Sciences, University of California Merced, Merced, California, United States of America, 2 University of the Pacific, Arthur A. Dugoni School of Dentistry, San Francisco, California, United States of America a11111 *
[email protected] Abstract Hepatitis C virus (HCV) actively evades host interferon (IFN) responses but the mechanisms of how it does so are not completely understood. In this study, we present evidence for an HCV OPEN ACCESS factor that contributes to the suppression of retinoic-acid-inducible gene-I (RIG-I)-mediated IFN Citation: Park SB, Seronello S, Mayer W, Ojcius DM induction. Expression of frameshift/alternate reading frame protein (F/ARFP) from HCV -2/+1 (2016) Hepatitis C Virus Frameshift/Alternate Reading Frame Protein Suppresses Interferon frame in Huh7 hepatoma cells suppressed type I IFN responses stimulated by HCV RNA path- Responses Mediated by Pattern Recognition ogen-associated molecular pattern (PAMP) and poly(IC). The suppression occurred indepen- Receptor Retinoic-Acid-Inducible Gene-I. PLoS ONE dently of other HCV factors; and activation of interferon stimulated genes, TNFα,IFN-λ1, and 11(7): e0158419. doi:10.1371/journal.pone.0158419 IFN-λ2/3 was likewise suppressed by HCV F/ARFP. Point mutations in the full-length HCV Editor: Shibo Jiang, Shanghai Medical College, sequence (JFH1 genotype 2a strain) were made to introduce premature termination codons in Fudan University, CHINA the -2/+1 reading frame coding for F/ARFP while preserving the original reading frame, which Received: February 26, 2016 enhanced IFNα and IFNβ induction by HCV.