Figure 7

The number of proliferating CMZ progenitors is increased in lep/ptc2 , while proliferation rate is unaffected. (A, B) BrdU 'pulse' in sibling (A) and lep/ptc2 mutants (B). BrdU⁺ cells are observed throughout the CMZ. (C, D) After an 8 hour 'chase', BrdU⁺ cells are observed at the CMZ, as well as within the retina of sibling (C) and lep/ptc2 mutants (D). E, F) PH3 labeling in sibling (E) and lep/ptc2 (F) at 64hpf. G) Quantification of BrdU⁺ cells in sibling and lep/ptc2 after 'pulse-chase' experiment. lep/ptc2 retinas contained 67% more BrdU⁺ cells than sibling retinas at 64hpf. After an 8 hour 'chase', the number of BrdU⁺ cells increased by almost identical ratios in siblings (2.31-fold increase) and lep/ptc2 mutants (2.29-fold increase, ***p < 0.0001). H) Quantification of BrdU- and PH3-positive cells as a percentage of total retinal cells in lep/ptc2 and wild-type siblings at 64hpf. The proportion of both BrdU⁺ and PH3⁺ cells increased by similar ratios (1.34-fold increase, **p < 0.001 and 1.36-fold increase, *p < 0.01, respectively).