FIGURE 3.

In vitro dephosphorylation of Syk Tyr(P) sites by TULA-2. Recombinant human Syk (0.5 μg/ml) and TULA-2 PTP domain (0, 0.03, or 0.12 μg/ml) were incubated at 37 °C for the indicated time periods, and the amounts of phosphorylation at Tyr-352 and Tyr-525/526 and total Syk in the samples were detected by immunoblotting. The phosphorylation level was quantified and normalized for the amount of total Syk in each sample and is shown at the bottom of the panel. A value of 1.0 was assigned to the sample in the absence of TULA-2.