(A) In situ hybridization analysis of pknox1 expression on stage 40 retinal sections. The right panels shows an enlargement of the CMZ region delineated with dotted lines. (B) Lateral views (left panels), head dorsal views (middle panels) and dissected eyes (right panels) of stage 40 tadpoles following two-cell stage microinjection of pknox1-5-mismatch-MO (control) or pknox1-MO. The asterisk indicates the injected side. (C) Quantification of dissected eye area. (D) Analysis of EdU-labeled replication foci (45 min-pulse) in the CMZ of tadpoles injected as in (B). Enlargements of the CMZ tip (dotted lines) are shown on the right. Early (red arrows) and mid/late profiles (white arrows) were distinguished. (E) Corresponding quantification. (F) In situ hybridization analysis of c-Myc expression on stage 40 retinal sections from tadpoles injected as in (B). (G–L) EdU incorporation assays (3-hr pulse) analyzed on retinal sections from stage 40 tadpoles. (G, H) shows the effect of pknox1 knockdown (injection of pknox1-5-mismatch-MO (control) or pknox1-MO). (I, J) shows the synergistic effects of pknox1 and Yap (injection of GFP mRNA and either ß-gal mRNA (control), Yap + ß-gal mRNA (Yap), pknox1 + ß-gal mRNA (pknox1), Yap + pknox1 mRNA (Yap + pknox1)). (K, L) shows the rescue of Yap overexpression by pknox1 knockdown (injection of either pknox1-5-mismatch-MO + ß-gal mRNA (control), pknox1-MO + ß-gal mRNA (pknox1-MO), pknox1-5-mismatch-MO + Yap mRNA (Yap), pknox1-MO + Yap mRNA (Yap + pknox-MO)). Of note, a suboptimal dose of pknox1-MO was used for the rescue experiment so that it does not alone give any eye phenotype. The total number of analyzed retinas per condition is indicated in each bar. Scale bar = 1 mm in (B) and 40 µm for all other panels.