S100A4Δ8 exhibits comparable myosin-IIA binding activity to wild-type S100A4. (A) Fluorescence anisotropy measurements of S100A4Δ8 binding to FITC-MIIA1904-1927. Values represent the mean ± standard deviation from two independent experiments. A KD of 0.51 ± 0.05 μM was determined from the fit to a single site saturation binding curve. (B) Representative gel of myosin-IIA disassembly assays performed at a ratio of 1:1 S100A4 dimer:myosin-IIA rod. 1 – myosin-IIA in the absence of S100A4; 2 – myosin-IIA in the presence of S100A4Δ8; 3 – myosin-IIA in the presence of wild-type S100A4 (m = reaction mixture, s = supernatant). (C) Quantification of disassembly assays. Values represent the mean ± standard deviation from two independent experiments.