Effects of C0C2, C1C2, C0C1m, and C1m on total Ca²⁺-independent and -dependent force. Effects of 10, 20, and 30 μM protein are shown on total force at pCa 4.5 (black bars) and Ca²⁺-independent force at pCa 9.0 (gray bars). Ca²⁺-activated force (white bars) is force at pCa 4.5 minus force at pCa 9.0. Washout (Wash) shows force values after a 20-min incubation in relaxing solutions without added proteins.