Fig. 4

a Equilibrium binding of eIF4A1 and eIF4A2 to RNA substrates. Direct fluorescence polarization measurement of 5′ FAM-RNA/eIF4A association for wild-type eIF4A1 (gold) and eIF4A2 (red) in the absence (control) or presence (+ silvestrol) of 10 μM silvestrol. Representative plot for 20 nt (AG)₁₀ (solid lines), (CAA)₆CA (dashed lines) oligo association. Raw data were converted to changes in anisotropy. Shown are the mean ± SD of triplicates. b Dissociation constants (KD) of the binding of eIF4A1 and eIF4A2 to different FAM-labeled RNAs in the presence and absence of silvestrol. c Schematic representation of the competition experiments with simultaneous incubation of multiple RNAs with eIF4A. The binding of eIF4A1 and eIF4A2 with and without silvestrol to labeled (AG)₁₀ in the presence of (CAA)₆CA competitor ssRNA at increasing molar excess was analyzed using EMSA. Dissociation constants have been derived from fitting the binding data. Data represents mean ± SD, n = 3