Exclusion of Gwl from the nucleus in prophase requires Polo and Cdk consensus sites and is required for timely mitotic progression. Expression of Gwl-GFP wt, PoloA, or CdkA was induced and cells were filmed one day later. (A) Gwl-GFP is nuclear in interphase and becomes cytoplasmic and excluded from the nucleus in prophase. After NEBD (T0), Gwl-GFP becomes diffuse throughout the cell and returns to nuclei during cytokinesis. Bar, 5 µm. (B and C) Mutation of Polo or Cdk consensus sites in the central region of Gwl-GFP prevents its nuclear exclusion in prophase. (D) Expression of Gwl-PoloA-GFP or Gwl-CdkA-GFP extends early mitosis. The time between estimated NEBD (loss of round outline of NE) and anaphase (cell elongation) was measured and shown in a box plot (wt: n = 37 cells; PoloA: n = 26 cells; CdkA: n = 67 cells). Asterisks: P < 0.001 after Student t test.
