Mitotic cyclins provide both redundant and specific function during mitosis. (A–C) Embryos expressing histone-GFP (top) or GFP-Polo (bottom) were imaged through mitosis 13. (A) Control embryos injected with LacI dsRNA. (B) Embryos injected with CycA and CycB dsRNA. Note that chromosomes fail to congress (02:36) or properly recruit GFP-Polo onto kinetochores (02:23 and 04:23). (C) Embryos injected with CycB and CycB3 dsRNA. Note that nuclei exhibit a prolonged metaphase (06:26), extended GFP-Polo concentration on kinetochores in metaphase (08:42), and a truncated anaphase. Arrows highlight kinetochores that fail to reach centrosomes. The times given in parentheses identify the corresponding frames in Videos 1–6 (available).