Figure 6. Native PAGE analysis of RIG-I-EGCG interaction.

(A) Recombinant RIG-I was incubated with different RNAs shown above the gel and stained with Coomassie brilliant blue to detect RIG-I protein as indicated below the gel image. cssR27 is an unphosphorylated 27-mer ssRNA, dsR27 is 27-mer blunt ended dsRNA, shR9 triphosphorylated 60-mer short hairpin RNA and pIC₁₀₅ is poly(I∶C) of average length of 105 bp. A shift in RIG-I mobility was observed only with RNAs that induced RIG-I signaling and ATPase activity. (B) Mobility shift does not require ATP. RIG-I was incubated with or without dsR27 in the absence or presence of different amounts of ATP (given on top of the gel). The presence of dsR27 is denoted with + sign above the gel. The gel is stained with Coomassie brilliant blue. (C) EGCG induces different mobility of RIG-I. Increasing concentrations of EGCG and Clemizole were added to RIG-I-dsR27 complex. The presence dsR27 and identity of the compounds are given on the top of the gel. The gel is stained with Coomassie blue and the fainter material with altered electrophoretic mobility is identified with white asterisks. (D) Same as (C) except the gel is stained for RNA using ethidium bromide.