Fig. 4

CaM and CaM₃₄ binding to the NT peptide of the Ca_V1.2 channel N-terminus. GST pull-down assay for CaM (a) or CaM₃₄ (c) binding to NT. Protein bands are shown as CBB staining at different [Ca²⁺]. CaM bands are indicated by arrows. Plots of concentration-dependent binding with fitted curves of CaM (b) or CaM₃₄ (d) (0.1–50 μM) to NT at free, 100 nM, 10 μM and 2 mM Ca²⁺. Band densities were converted into molar ratio (CaM/GST-NT) and plotted against total [CaM] or [CaM₃₄] with symbols as indicated in each graph and with mean ± SE (n = 3–10). *P < 0.05, **P < 0.01, compared with CaM or CaM₃₄ binding to NT at the corresponding CaM or CaM₃₄ concentration with Ca²⁺-free condition for (b) and (d), respectively