Figure 6.

Both shJNK2 and shGAB2 impair growth factor–mediated Akt phosphorylation. GIPZ, shJNK2, and shGAB2 cells were serum starved and then treated with the indicated growth factors. (A) Cells were treated with HGF at indicated time points. Later, lysates were evaluated for pSrc, pERK, and pAkt. GAPDH was used to compare protein loading among samples. (B) Experiments were done as described in A, except cells were treated with Her1. (C) Experiments were done as described in A, except cells were treated with insulin. (D) Effect of Src inhibition on GAB2 tyrosine phosphorylation was tested by immunoprecipitating GAB2 from cell lysates. Western blot analysis was performed using phosphotyrosine and GAB2 primary antibodies. (E) Effects of HGF, Her1, and insulin treatment on GAB2 tyrosine phosphorylation and Src binding to GAB2 were assessed by immunoprecipitation of GAB2 and Western blot analysis using phosphotyrosine, GAB2, and Src primary antibodies.