14bp deletion spanning nucleotides 830-843 of feo. This produces a frameshift, resulting in a truncated protein of 305 amino acids, with an altered sequence from residues 277 to 305.
76.7% of cells in the brains of feoEA86/Y third instar larvae are polyploid. The proportion of cells in anaphase in the mutant larval brains is normal (13.4% for the mutant larvae, compared to 15.0% for control larvae) and the mitotic index is 0.40 (compared to the wild-type value of 0.60). 62.3% of cells in the brains of feoEA86/feoEA86 third instar larvae are polyploid. The proportion of cells in anaphase in the mutant larval brains is normal (18.6% for the mutant larvae, compared to 15.0% for control larvae) and the mitotic index is 0.24 (compared to the wild-type value of 0.60). 65.5% of cells in the brains of feoEA86/Df(1)v-L3 third instar larvae are polyploid. The proportion of cells in anaphase in the mutant larval brains is normal (14.8% for the mutant larvae, compared to 15.0% for control larvae) and the mitotic index is 0.35 (compared to the wild-type value of 0.60). Brains of feoEA86/Y male larvae do not show defects in the early stages of neuroblast and ganglion mother cell divisions; the cells have regular asters and metaphase figures and they enter anaphase normally.
Lefevre.
Maternal germline clonal analysis demonstrates cell lethality in homozygous clones.