Fig. 2

CaM and CaM₁₂ binding to CT1 peptide of the Ca_V1.2 channel. GST pull-down assay for CaM (a) or CaM₁₂ (c) binding to CT1. Protein bands are shown as Coomassie brilliant blue (CBB) staining at different [Ca²⁺]. CaM bands are indicated by arrows. Plots of concentration-dependent binding with fitted curves for CaM (b) and CaM₁₂ (d) (0.1–50 μM) to CT1 at ≈free, 100 nM, 10 μM, and 2 mM Ca²⁺. Band densities were converted into molar ratio (CaM/GST-CT1) and plotted against total [CaM] or [CaM₁₂] with symbols as indicated in each graph and with mean ± SE (n = 3–10). *P < 0.05, **P < 0.01, compared with corresponding bindings at Ca²⁺-free condition