Figure 5.

Aurora B phosphorylation is important for targeting Ncd to the spindle and spindle bipolarity. (A) Immunostaining of spindles in ncd¹ mutant oocytes carrying one Ncd-GFP transgene or one Ncd(S94A)-GFP transgene. Images were captured and modified using an identical setting. Bar, 10 µm. (B) GFP signal intensity relative to α-tubulin signal on the spindle. n = 34, 27, and 41. **, P < 0.01; ***, P < 0.001. Note that these were imaged using a different microscope to Fig. 2. (C) Spindle morphologies in oocytes. n = 31 and 42. (D and E) Aurora B (AurB) releases Ncd from 14-3-3 inhibition in oocytes analogously to the Ran–importin system, enabling Ncd to specifically bind spindle microtubules.