Fig. 2.
Effects of Abi1 deficiency on IL3-independent cell growth, SDF-induced chemotaxis, and F-actin remodeling of the p185Bcr-Abl-transformed Ba/F3 cells. a. IL3-independent growth of p185 Cas9 control cells (Cas9 Ctrl) and two p185 Abi1 knockout cell lines (KO2.3 and KO6.2). *P < 0.001 as compared to Cas9 Ctrl cells. b. Effects of Abi1 deficiency on SDF1α-induced chemotaxis. The p185 Cas9 control cells (Cas9 Ctrl) and two independent lines of p185 Abi1 knockout cells (KO2.3 and KO6.2) were tested in Transwell plate (1.0 × 105 /insert) for SDF1α (50 ng/ml) stimulated migration. The vertical axis shows the chemotactic index expressed as the average ratio +/- S.D. of migrated cells in the presence of SDF1α to those in the absence of SDF1α. The data was calculated from triplicate wells from a representative assay of three independent experiments. *P < 0.05 as compared to Cas9 Ctrl cells. c and d. Abi1 is required for Bcr-Abl-induced abnormal F-actin remodeling. Ba/F3, Cas9 Ctrl, KO2.3, and KO6.2 cells, as indicated, were fixed and stained with TRITC-conjugated phalloidin for F-actin (red) and DAPI for nucleus (blue). The cells with F-actin rich invadopodium structures were visualized by fluorescence microscopy, as shown by arrowheads (C, Cas9 Ctrl panel) and were counted (D, expressed as average percentage +/- S.D. of three randomly picked areas). *P < 0.001 as compared to Cas9 Ctrl cells