Fig. 6. Blocking apoptosis in PcG mutant clones restores wild-type-like neurogenesis. Confocal images of Pc+P35 clones labeled with CD8::GFP in the late third-instar central brain. A,C,E show the region around the junction of the central brain and optic lobe (dotted line); B,D,F,F' show high magnification of isolated clones. (A-D) Targeted expression of P35 in Pc mutant clones results in clones that contain a single large neuroblast cell (asterisk) expressing Mira (A,B) and Grh (C,D), whereas the adjacent GMCs (arrowheads) express low levels of Mira at the cortex (B and inset) or coexpress Grh and Pros in the nucleus (D shows an isolated clone adjacent to wild-type cells and the inset is a close-up view on the neuroblast and GMC). Nonneural stem cells within the clones express Elav (A,B) and Pros (C,D). (E-F') Neural progenitors survive in spite of the expression of Abd-A and are engaged in mitosis as indicated by PH3 immunoreactivity (G) at a frequency similar to wild-type controls (see Fig. 1J). (G) Quantification of the presence of neural progenitors and mitosis indicates a large degree of rescue of the three mutants by P35 (F).