TULA-2 dephosphorylation of Syk and association with Syk. (A) Active TULA-2 was purified from Sf9 cells, incubated with phosphorylated Syk for the indicated times, analyzed by Western blotting, and probed for phosphotyrosine, pY525/6 Syk, and total Syk. (B) NP-40 lysed lysates from convulxin-treated and untreated human platelets were precleared and incubated with GST-TULA-2 (H380A) or GST. Pulldowns were analyzed by Western blotting and probed for Syk and TULA-2. (C) NP-40 with 0.1% SDS-lysed lysates from convulxin-treated and untreated human platelets were precleared and incubated with rabbit IgG or anti–TULA-2 antibody. Immunoprecipitates were analyzed by Western blotting and probed for Syk and TULA-2. All blots are representative of 3 experiments.