Figure 4. Sensitivity analyses.

Selected time-varying response coefficients for phosphorylated Hsf1 for a 37°C–42°C heat shock are presented. The parameters not presented in this figure had negligible influence upon the Hsf1 phosphorylation dynamics over the 120 minute timescale examined. (A) Early response coefficients are shown. These influence the Hsf1 phosphorylation dynamics during the first ∼10 minutes, but do not significantly affect thermal adaptation in the longer term. (B) Late response coefficients. These mainly influence Hsf1 phosphorylation dynamics after ∼15 minutes leading to differences in the concentration of phosphorylated Hsf1 at the 120 minute time point. For instance, the parameter T_H has a positive response coefficient at 120 minutes, which means that an increment in its numerical value will result in increased accumulation of phosphorylated Hsf1 at 120 minutes. (C) Response coefficients calculated for the initial concentrations. An increased initial concentration of the Hsf1-Hsp90 complex leads to higher Hsf1 phosphorylation levels throughout the period of thermal adaptation examined.