Figure 5.

Activation-dependent interactions between SLAP and phospho-tyrosyl proteins are mediated by the SH2 domain of SLAP. Jurkat T cells were transiently transfected with wild-type or mutant forms of GST-SLAP. Transfected cells were activated with OKT3.14 and RAM antibody at 37°C for 2 min. The activated and nonactivated cells were lysed and incubated with glutathione-Sepharose beads. Precipitated protein complexes were separated by 9% SDS/PAGE and blotted with anti-p-Tyr or anti-GST antibodies. The positions for the known SLAP associating proteins are indicated. WT, wild-type SLAP; RK, SLAP Arg-111 changed to Lys; ΔT, 64-aa deletion at C terminus of SLAP.