(A) In vitro dsRNA binding assay for eVP35
215–240 and batVP35 159–284. Fractional binding of batVP35 was
normalized to eVP35, and error bars represent SD for the triplicate. RNA binding
was assessed twice. (B) Western blot analysis of poly(I:C) pull-downs of the
indicated FLAG-tagged VP35 constructs. IP, immunoprecipitation; WCL, whole-cell
lysate. Poly(I:C) pull-downs were repeated twice. (C-E) IFN-β luciferase
reporter assay stimulated by overexpression of (C) RIG-I N, (D) TBK1, or (E)
IKKε in the presence of FLAG-tagged eVP35 or batVP35 (500 and 50 ng).
Error bars represent the SEM for triplicate experiments. VP35 expression was
assessed by western blot for the FLAG epitope tag, and the western blot was
aligned to the corresponding samples in the graph. (F) IFN-β reporter
assay in cells transfected as indicated. IFN-β promoter activity was
assessed as in (C). VP35 expression was assessed for the highest concentration
(500 ng) as in (C) (inset). Statistical significance was assessed using a oneway
ANOVA and Tukey’s test: ****p < 0.0001, **p<0.01. E refers
to empty vector. IFN-β luciferase reporter assays were repeated at least
three times. See also Figures
S2 and S3.