Fig. 3.

Loss of B55γ by RNAi misorients the mitotic spindle. (A) Schematic representation of the mitotic spindle on the L-shape micropattern. The mitotic spindle and the centrosomes are shown in cyan, and chromosomes are in magenta. Spindle orientation angles (α°) were determined as depicted, with spindle angle measured relative to the hypotenuse of the micropattern (0°), as shown. (B,C) HeLa cells on an L-shape fibronectin micropattern that were either treated with control siRNAs (B) or RNAi against B55γ (C). Cells were stained for γ-tubulin (green) and DNA (blue). (D) Frequency of angular distribution of spindle positioning from 0°–15°, 16°–45°, and more than 45°. Note the change in the axis of spindle orientation in cells depleted of B55γ. Data are mean±s.d. of n>50 cells. ***P<0.0001 (two-tailed Student's t-test).