The myonuclei in sls^g05/sls^e4 mutant third instar larval striated muscle are not properly distributed.

Both the sls^e4/sls^g05 and sls^e4/sls^S002001 allelic combinations produce long, thin pupae.

sls^g05/sls^e4 mutant third instar larvae examined just prior to puparium formation display structural abnormalities of muscle fibers.

Homozygotes survive until the larval-pupal transition. There is considerable nuclear size variability in the neuroblasts of homozygous larvae (in contrast to wild type), and several cells are in mitosis (most wild-type neuroblasts are in interphase). Most of the mitotic nuclei are polyploid and show both chromosome fragmentation and/or irregular condensation. Additional mitotic defects such as premature sister chromatid separation, aneuploidy and chromosome breakage are also seen. Similar defects are seen in sls^e4/sls^110ry-, sls^e4/sls^g65 and sls^e4/sls^j1D7 larvae. Neuroblasts from heterozygous larvae show a minor increase in chromosome defects compared to wild type. Polytene chromosomes from the salivary glands of homozygotes are indistinguishable from wild type.