Figure 4

Depletion of DDX3 in p53 ^−/− HCT116 cells and reintroduction of p53 in the DDX3-knockdown HCT116 cells elicited no effect on the multipolar mitosis. (a) Depletion of DDX3 elicited no effect on the multipolar mitosis in p53 ^−/− HCT116 cells. Confocal images of control or DDX3-knockdown mitotic cells classified as normal bipolar mitosis (N), pseudo-bipolar mitosis by centrosome inactivation/clustering (I/C) or multipolar mitosis (M). Each typical mitotic cell is shown at higher magnification in the right column. Cells were immunostained with DDX3 (red), γ-tubulin (green) and DNA (blue). Images are shown as the maximum projections of confocal Z stacks. Scale bar = 5 μm. The proportions of bipolar mitosis (two centrosomes), pseudo-bipolar mitosis (more than two centrosomes) and multipolar mitosis in the control and DDX3-knockdown cells were statistically analyzed (right panel). Data are shown as average value ± S.D. calculated from two independent experiments. (n), the number of cells analyzed. (b) Reintroduction of p53 was insufficient to rescue the multipolar mitosis caused by knockdown of DDX3 in HCT116 cells. Cells were immunostained with DDX3 (red), p53 (blue), γ-tubulin (green) and DNA (gray). Images are shown as the maximum projections of confocal Z stacks. Scale bar = 5 μm. Data are shown as average value ± S.D. calculated from two independent experiments. (n), the number of cells analyzed.