γTub37C APL10 mutant embryos. (A) Anaphase I arrest. (B) Anastral spindles associated with MII metaphase chromosomes (inset) from an embryo containing 6 or more anastral spindles and a polar body with 1N chromosomes. (C) Astral cycle 1 mitotic spindle containing a haploid set of chromosomes. (D) Two small astral spindles associated with interphase or prometaphase nuclei from an embryo containing ~20 astral spindles (~cycle 6) and two pairs of MII-like anastral spindles without central spindle bodies. (E) Wild-type spindles. Top, anaphase II spindle with central spindle pole body (large arrow) and segregating haploid chromosome sets (inset); middle, cycle 1 mitotic spindle containing two haploid chromosome sets (inset); bottom, cycle 6 mitotic spindle. Tubulin, red; Ncd-GFP, green; DNA, blue. Bars, 5 μm.