Figure 5

SPRY1 silencing increases MAPK activation and endothelial cell proliferation by adapting cell-cycle regulator expression. ABAE cells were transfected with non-silencing (Control) or SPRY1 siRNA for 48 h. A. Total protein was extracted from these cells and the level of phospho-Erk1/2 protein was measured by Western blotting. The total level of Erk1/2 protein was used as an internal control. Bottom panel: quantification of the top panel. A densitometry analysis was performed using ImageJ software showing phospho-Erk1/2/total Erk1/2 intensity. B. Proliferation was assayed 48 hours after transfection by measuring BrdU incorporation. C. cyclinD1 and p21 mRNA expression quantified by qRT-PCR from ABAE cells 48 h post-tranfection. Data were normalized to the level of GAPDH transcript. Mean fold change versus control is shown with the SD (line above the bar, n = 3), *: significance at p < 0.05. The results shown are representative of at least three independent cell transfections.