Figure 3.

Cell proliferation and phosphorylation assays. (A and B) Proliferation. Proliferation was assessed by [³H]thymidine incorporation in WT MLECs treated with different concentrations of α1(IV)NC1 (proliferation inhibits 60.11% at 1 μM, 48.33% at 0.75 μM, and 31.39% at 0.5 μM). In α1 integrin^–/– MLECs upon treatment with different concentrations of α1(IV)NC1, using 20% FCS or 1 μM α3(IV)NC1 (proliferation inhibits 62.22% and 63.71% in WT and α1 integrin^–/– MLECs) as controls. The results are shown as the mean of 3 independent experiments. (C and D) FAK phosphorylation. Serum-starved WT MLECs or α1 integrin^–/– MLECs were plated on type IV collagen–coated dishes in incomplete medium supplemented with or without α1(IV)NC1 for 0–60 minutes as shown in the figure, and lysates were analyzed by Western blot. Immunoblots of phosphorylated FAK (top blot) and total signaling FAK protein (bottom blot) in C and D were performed as described previously (35).