RLC phosphorylation influences maximal force production and Ca ²⁺ sensitivity. (A) Normalized tension plotted against pCa shows the relative differences in Ca²⁺ sensitivity of contraction between all groups. (B and C) F_max, or maximal stress (fixed effects: genotype: P = 0.015; treatment: P = 0.001; genotype*treatment: P = 0.003; B), and pCa₅₀ values from the three-parameter Hill fits (fixed effects: genotype: P = 0.015; treatment: P < 0.001; genotype*treatment: P = 0.005; C; Fig. 2 and Table 1). Averages represent mean ± SEM, with individual data points shown where applicable. The number of biological and technical replicates is listed in Table 1.