Figure S15.

Effect of allosteric TnC–TnI–actin–Ca²⁺ interaction parameter, ε_o, on resting tension at observed baseline calcium level (0.143 µM) and when [Ca²⁺] is reduced to 0.05 µM. MUSICO simulations using the five-state cross-bridge cycle predicted a slight decrease in resting tension at both baseline [Ca²⁺] for decrease by three orders of magnitude in ε_o, but significant resting tension remains even at extremely low ε_o values. Parameters used in simulations are the same as used in the five-state model simulations shown in Fig. 3.