Figure 5.

ADP binding depopulates the myosin SRX state more in STF-WT than in STF-R403Q. Scatter plots showing the effect of ATP chase versus ADP chase in PcSTF-WT and PcSTF-R403Q for (A) A_slow, (B) k_fast, and (C) k_slow. All parameters are reported on an absolute scale (amplitudes in % and rates in s^-1). PcSTF-WT and PcSTF-R403Q refer to porcine cardiac synthetic thick filaments made of WT and mutant R403Q myosin, respectively. Statistical differences presented are based on two-way ANOVA and subsequent post hoc Tukey’s pair-wise comparisons (∗∗p < 0.01; ∗∗∗p < 0.001). Data are expressed as the mean ± SEM (n ≥ 6 for each). NS, not significant; SRX, super-relaxed.