Pathway for Tn dissociation. Protein interactions are noted by lines connecting the letters with A, Tm, T, I, C, being actin, tropomyosin, TnT, TnI and TnC. Steps (1) or (2) can limit rate of Tn dissociation while step (1) is involved in regulation. Step (1) is dissociation of the regulatory domain of TnI from actin-Tm and its binding to the regulatory domain of TnC. Step (2) is TnT dissociation from actin-Tm. Step (1) limits the B-state region the rate of Tn dissociation while step (2) limits C- and M-state region dissociation rate. Calcium and strong cross-bridges influence step (1) while strong cross-bridges also influence step (2).