Fig. 5

ASC proneurals contribute to late-born NB identity and progeny fidelity. A Eagle-lacz expression in stage 10 embryos. In wt the NB 2-4 and 3-3 is clearly visible, expressing eagle and Dpn robustly. In B57 mutant embryos 2-4 in not clearly seen, as it expresses eagle weakly. B Close-ups of embryos in A, show that the 2-4 neuroblast is also temporarily stalled since it does not express Dpn. C Eagle-lacZ expression shows that at stage 11 all four positive neuroblasts have delaminated in Df(1)scB57. D Stage 12 embryos do not show major differences in eagle-lacZ positive cells. E By stage 13, the medial glia, progeny of 6-4, that move towards the midline are absent or have lower expression in the Df(1)scB57. F By stage 15 the nerve cord shows severe disorganization in mutants. G Stage 15 VNC close-ups show an Anterior-Posterior Commissural axonal collapse, no medial glia (asterisks in wt), a diminished EG/EL neuronal population (boxed), an EW neuron missing (left arrowhead) whereas the other EW (right arrowhead) is sending its axon laterally instead of posteriorly