nerfin-1159/Df(3L)Exel6086 embryos show strongly disorganized Fas2-immunopositive fascicles and disorganized or absent ap-expressing axons, despite having a similar number of ap-expressing neurons as controls.
Larval optic lobe nerfin-1159/nerfin-1159 mutant clones include ectopic neuroblasts, located where post-mitotic neurons should be. These neuroblasts exhibit proliferation potential as shown by an increase in the number of mitotic cells in these clones, and form tumors at the adult stage. Medulla neurons are generated normally, but soon begin to de-differentiate, suggesting that the origin of these ectopic neuroblasts is de-differentiation of neurons. The number of GMCs does not significantly change in nerfin-1159/nerfin-1159 mutant clones.