Analysis of a Budding Yeast Cell Cycle Model Using the Shapes of Local Sensitivity Functions

The Chen et al. (Mol Biol Cell 2000, 11, 369–391) budding yeast cell cycle model is a biochemical kinetic model that describes how the controlling protein concentrations change during a proliferation cycle. Time dependence of local sensitivity coefficients was calculated for all variables and parameters of the model. Some of the local sensitivity coefficients—time functions could also be obtained from another one by multiplying it with a constant, which means that these functions exhibit global similarity. Local similarity of the sensitivity functions was also detected. The distance of the shapes of two scaled sensitivity functions was defined by the integrated squared difference of these functions. The distance matrices of function shapes were interpreted by a clustering method, and the shapes could be sorted to two main groups for each model variable. The presence of the global similarity of sensitivity functions means that the change of some enzyme activities can be fully compensated by changing the activity of other enzymes. This feature can be related to the robustness of living organisms. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 710–720, 2008