Figure 8.

PI3K and JNK activities are necessary for collagen I–induced changes. (A) NMuMG/E10 cells were cultured on noncoated or collagen I-coated dishes for 2 d in the presence of the vehicle DMSO (a and b), the PI3K inhibitor LY294002 (10 μM; c and d), or the JNK inhibitor SP600125 (10 μM; e and f). Photographs were taken using a 10× objective. (B and C) RIPA extracts were made from cells cultured on noncoated or collagen I-coated dishes for 3 h in the presence of DMSO, LY294002 (10 μM; B and C), or SP600125 (10 μM; C). Pull-down assays for Rac-GTP and total Rac were performed as in Figure 6A. Immunoblots were done for phospho-Akt (Ser479), total Akt1, phospho-JNK (Thr183/Thy185) and total JNK1 (B), and with N-cadherin and GAPDH (C). (D) N-cadherin mRNA levels were analyzed by quantitative real-time PCR as in Figure 3D (∗p < 0.05, DMSO col versus LY294002 col or SP600125 col).