Fig. 8. Expression of a ZM3-resistant Aurora A mutant restores spindle bipolarity. (A) Immunoblots and immunofluorescence images of DLD-1 cell lines showing that the tetracycline-induced wild-type and W277A Aurora A proteins localise to the spindle poles. The arrow indicates exogenous Myc-tagged Aurora A and the asterisk indicates endogenous protein. (B) Following tetracycline (Tet) induction, cells were exposed to 2 µM ZM3 and MG132 for 2 hours then analysed by immunofluorescence. Images show examples of monopolar spindles in the absence of W277A expression. Bar, 5 µm. (C) Bar graph quantifying monopolar spindles. The values represent the mean ± s.e.m. derived from three independent experiments in which at least 100 mitotic cells were scored. (D) Line graph showing proportion of monopolar spindles over a range of ZM3 concentrations. The data is derived from a single representative experiment in which at least 100 mitotic cells were scored per concentration.