for nonspecific knockdown of IRF1. The selected target sequences were tested so as not to match any known murine gene (other than murine IRF1) sequences by using NCBI nucleotide BLAST at http://www.ncbi.nlm.nih.gov/BLAST/. Transfection was per- formed according to the manufacturer’s protocol. IRF1 siRNA and scrambled siRNA were used at a concentration of 50 mM. IRF1 gene expression following knockdown was quantified by qRT-PCR. Statistical Analyses Data are represented as the mean of three replicates 6 standard error of the mean (SEM). A one-way ANOVA with a Tukey post- test was used to compare the means of 4 concentrations of Bay 11- 7082 in inhibition of NF-kB nuclear translocation. An unpaired t- test was used to compare the means of two groups where References 1. Stetson D, Medzhitov R (2006) Type I interferon in host defense. Immunity 25: 373–381. 2. Pinkerton KE, Barry BE, O’Neil JJ, Raub JA, Pratt PC, et al. 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Witte MB, Thornton FJ, Efron DF, Barbul A (2000) Enhancement of fibroblast collagen synthesis by nitric oxide. Nitric Oxide 4: 572–582. PLoS ONE | www.plosone.org 11 February 2012 | Volume 7 | Issue 2 | e31688