Fig. S2.

Relates to Fig. 1C. MKK6 phosphorylation by 0.01 μM ASK1 kinase domain with concentrations of ASK1(269–658) substoichiometric to the substrate (MKK6), but up to 100-fold excess to the ASK1 kinase domain. MKK6 is held constant (3 μM), and phosphorylation is monitored by Western blot analysis. Quantitation of independent triplicate experiments is shown. Each band was normalized to the band intensity of the kinase alone at the 10-min time point for that experiment. Mean values are plotted, with error bars representing the SEM.