No cell division occurs in the ectoderm after the blastoderm stage in homozygotes at the 29^oC. Postblastoderm cell divisions do take place in homozygous embryos, at 18^oC, but at a lower frequency than in wild-type, and the length of the cell cycle, in particular the length of the mitotic phase is increased.

There is no evidence of chromosome condensation, nuclear envelope breakdown or spindle formation between 3 and 12 hours after egg deposition (at 25^oC), in contrast to wild type embryos. Mutants show a nonspecific reduction in the number of differentiated cuticular structures.