Fig. 5. ARAP2 and the cytoskeleton. (A) Effect of expression levels of ARAP2 on cytoskeletal markers in U118 cells. Untreated cells (control, left panel), cells expressing Flag tagged ARAP2 (middle panel), or cells with reduced expression of ARAP2 (ARAP2-siRNA, right panel) were replated on fibronectin-coated slide for 4 hr in serum free media, fixed and stained for ARAP2 and either paxillin, vinculin, phosphotyrosine (pY), or actin. Bars 10 µm. (B) ARAP2 protein levels in cells transfected with siRNA and siRNA-resistant plasmids. U118 cells were transfected with siRNA directed to the 3'UTR of the ARAP2 message and plasmids directing expression of the indicated proteins. Cell lysates were analyzed by immunoblotting using antiserum (1185) raised against ARAP2 and an antiFLAG antibody. Bars, 10 µm.