Figure 1.

A, structure of the core domain of the Tn complex (PDB code 1J1E) with each of the residues that were selected for this study highlighted. The troponin complex proteins are colored white (cTnC), gray (cTnT), and black (cTnI). B, the isolated N-cTnC domain bound to Ca²⁺ used in the PMF simulations. Helices and mutation sites are labeled. C, the N-cTnC domain bound to the TnI_SW and Ca²⁺ is the system used in the TnI_SW binding simulations. D, a schematic of the N-cTnC construct. The helices, Ca²⁺-binding loop, and the residues being examined in this study are labeled.