Figure 7
(a) Immunoblots of T84 epithelial cell whole cell lysates demonstrate Gab2 was phosphorylated following 6 h of IFNγ stimulation and this was inhibited by transfection of Fyn-targeting siRNA. Levels of IFNγ-stimulated phospho-Akt were also reduced by Fyn siRNA. (b) IFNγ-stimulated increases of Gab2 and Akt phosphorylation were reduced by the Src inhibitor PP1 (125 nM, 90 min post-stimulation). (c) Treatment of T84 cells with Fyn or Gab2 siRNA reduces PI3K(p85α) and Gab2 interaction with STAT5b at 6 h after treatment with IFNγ (10 ng/ml; images are representative of two experiments). Fyn- and Gab2-siRNA-treated cells demonstrated reduced IFNγ-stimulated tyrosine phosphorylation of products putatively identified as STAT5, Gab2 and p85. (d) Reduced association of STAT5b with p85α and Gab2 in STAT5b co-immunoprecipitates following IFNγ stimulation (6 h) in the presence of PP1. Input and nonimmune controls are shown.
