Model results for three different levels of expression of the oncogene Bcl-x
. (A) ATP level as a function of time after IL-3 growth factor removal. (B) Fraction of surviving cells for different time lags after IL-3 removal. Different symbol shapes and colors refer to the same cell types in both panels A and B. They correspond to experimental data from Ref.  for three cell types, labeled as "Bcl-xL", "Bcl-xL 1E1", and "Bcl-xL 4.1", which have low, high, and higher expression of Bcl-xL, respectively. Continuous lines correspond to model results from Equations (1)-(5) with a(0) = 3.54 fmol/cell, ATP* = 0.32 fmol/cell, and τ
= 19.9 hours for all three cell types. The inferred values of the pairs (μ,σ) for the cell types "Bcl-xL", "Bcl-xL 1E1", and "Bcl-xL 4.1" are (0.63, 0.074), (-0.38, 0.27), and (-1.53, 0.58), respectively.