Figure 5

Binding of unlabeled calmodulin to Myo1c IQ peptides Fluorescence intensity during titration of a mixture of 50 μM unlabeled calmodulin and 500 nM Alexa calmodulin (used as a reporter) with IQ peptides (total concentration). Thin solid lines: fit with equation (7) assuming m = 1. Dashed lines: fit with equation (7) assuming m = 2 and final fluorescence from m = 1 fit. Dotted lines: results predicted from Table 1 if unlabeled calmodulin does not affect the Alexa-calmodulin – IQ peptide equilibrium. Thick solid lines (IQ4 only): fit with equation (4). Error bars indicate standard deviation with n = 4. Note difference in the abscissa scale for IQ4.