FIGURE 7.

SPR binding analysis of correct and mixed complexes. eIF4E (A and D) or eIFiso4E (B and C) were tested for binding to the respective immobilized proteins eIF4G (A and B) or eIFiso4G (C and D). The running buffer contained 20 mm HEPES, 100 mm KCl, 1.0 mm DTT, 0.1 mm EDTA, 100 μm m⁷GTP, 5% glycerol, 0.01% Tween 20, and 0.1 mg/ml BSA, pH 7.6. Starting at 50 nm, a 3-fold dilution series of eIFiso4E or eIF4E were tested in triplicate. The response data were globally fit using Scrubber2 (Biologic Software Pty Ltd) to a 1:1 interaction model to extract binding constants.