Fig. 2. Chromosome misalignment in mitch mutants. (A-D) Brain neuroblasts from wild-type (A,B) and mitch¹ (C,D) were stained for chromosomes (blue) and microtubules (green). At metaphase (A,C), chromosomes are correctly aligned at the metaphase plate in wild-type (A), whereas the chromosomes are mis-oriented in mitch mutants (C) with some chromosomes abnormally situated near the pole (arrow). At anaphase (B,D), the normal even distribution of chromatids (B) is disrupted in mitch mutants (D) so as to produce lagging chromosomes (arrow); moderate chromosome overcondensation is also apparent in this mutant anaphase. In all mitch mutant mitotic figures, the spindles are morphologically normal. Bar, 5 µm.