Figure 2.

(a) Mass-spectrometry-based quantitation of Erkp and Mekpp under PTP perturbation (top) and Erk perturbation (bottom). The amounts of Erkp and Mekpp at 30 min, quantified by the AQUA method (see Materials and Methods and Gerber et al. (41)), are plotted at the indicated concentrations of the perturbed enzymes. Error bars show the standard error of the mean of three technical replicates (same sample, three different reaction tubes). (b) Western blot-based quantitation of Erkp and Mekpp under PTP perturbation conditions and Erk perturbation conditions. Amounts of Erkp and Mekpp, quantified as described in Materials and Methods, are plotted at the concentrations of the perturbed enzymes after 30 min of reaction time. Error bars show the standard error of the mean of three technical replicates (same sample, three different reaction tubes). To see this figure in color, go online.