FIGURE 4.

Analysis of lifetimes by a three-state model. Plots of reciprocal off-rates (A–D) or fraction of bonds (F–I and K–N) of the short (□), intermediate (○), and long ()-lived states evaluated from simultaneously fitting the three-state model to the survival frequency (supplemental Fig. S2, upper rows) and rupture probability (supplemental Fig. S2, lower rows) versus lifetime data measured in Ca²⁺/Mg²⁺ (A, F, K), Ca²⁺/Mg²⁺/CXCL12 (B, G, L), Mg²⁺/EGTA (C, H, M), or Mn²⁺ (D, I, M) in the absence (F–I) and presence (K–N) of XVA143. The reciprocal off-rates in A–D were required to fit both data in the absence and presence of XVA143, which were superimposed in E and fitted by the Bell model (Equation 3, lines) with parameters listed in Table 1. J, reciprocal off-rates and associated fractions of the three states were used to calculate the force-dependent average lifetimes that include short (<10 s) as well as long (>10 s) subpopulations.