Fig. 2.

Effects of R58Q mutation on isolated cardiac myosin and RLC. (A) SDS-PAGE of RLC-depleted porcine β-cardiac myosin, and myosin reconstituted with either WT- and/or R58Q-RLC. The endogenous (eRLC) and recombinant RLC (rRLC) are labelled accordingly. (B) F-actin dependent ATPase activity of RLC-exchanged β-cardiac myosins from (A) (for details see Materials and Methods). Data points fitted to the Michaelis-Menten equation (solid lines). (C) Protein stability of WT- and R58Q-RLCs were assessed by Micro-scale Thermophoresis (MST) against increasing concentrations of Guanidine Hydrochloride (GdnHCl). Data points between 0 and 3 mol/L GdnHCl were fitted to a Hill equation (solid lines). (D) Binding of WT- and R58Q-RLC to N-terminal (C0C2) domains of cMyBP-C assessed by MST. Means ± SEM (n = 4–6 for C0C2; n = 1 for C3C5).