mitosis & nuclear chromosome
Mutants die as late third instar larvae or shortly after pupariation and have very small imaginal discs. Neuroblasts of hemizygous mus101lcd/Y third instar larvae have numerous chromosomes with striking undercondensation of pericentric heterochromatic regions. Most of the mitoses in larval brains show more extreme defects, characteristically grossly undercondensed chromatin or chromosome breakage. These defects are also seen in neuroblasts of mus101lcd/Df(1)HA92 female hemizygotes.