Supplementary Figure 6: Csk affects tyrosine phosphorylation of Lck in solution.

(a) Left, immunoblots showing the time course of ATP-triggered phosphorylation of Y394 and Y505 of 86 nM Lck in solution, with or without 86 nM Csk. Experiments shown here were essentially the same as Fig. 6a except in the absence of liposomes. Right, immunoblots quantified, normalized and plotted against time in a logarithmic scale. pY505 WB signals were and normalized to the last data point (90 min) of the “m-Lck + m-Csk” condition as shown in Fig. 6a, and plotted against time in a logarithmic scale; pY394 WB signals were quantified and normalized to the last data point (90 min) of the “m-Lck” condition as shown in Fig. 6a. (b) Left, immunoblots showing the time course of ATP-triggered phosphorylation of Lck at 8.6 nM concentration, with or without 86 nM Csk. Experiments shown here were essentially the same as Fig. 6b except in the absence of liposomes. Right, quantification plots of immunoblots shown on the left. pY505 WB signals were normalized to the last data point (90 min) of the “m-Lck + m-Csk” condition in Fig. 6b; pY394 WB signals were normalized to the last data point (90 min) of the “m-Lck” condition in Fig. 6b. For each condition, the WB signal at time zero was arbitrary plotted as a data point at 0.1 min. The dashed lines indicate 50% phosphorylation. All experiments shown here were performed side-by-side with experiments shown in Fig. 6a,b. Original images of blots can be found in Supplementary Fig. 9.