Figure 2—source data 1.

(A–C’) Confocal images of frontal cryo-sections of Tg(E1-bhlhe40:GFP) embryos immunostained for GFP (green) and β-catenin (white) and counterstained with Hoechst (blue). Note that the RPE rapidly decreases its thickness white straight line in (A–C) and cells change from columnar (14 hpf, arrow in A’) to cuboidal (16 hpf, arrow in B’) and then flat shape (22 hpf, arrow in C’). White dashed lines delineate eye contour and virtual lumen in A–C. (D–E’) Confocal images of the posterior RPE (D, D’) and neural retina (NR) (E, E’) regions of an eye cup dissected from 30 hpf Tg(E1-bhlhe40:GFP) embryos immunostained for GFP (green) and β-catenin (white) and counterstained with Hoechst (blue). Images in D’, E’ are high power views of the areas boxed in white box in D, E. Note the hexagonal morphology (yellow arrow in D’) of RPE cells (average area 354.8 ± 100.3 μm²) in contrast to the small and roundish cross-section of retinal progenitors (average area 22.5 ± 2.9 μm²; yellow arrow in E’). (F) The graph represents the average area of individual OV progenitors and NR and RPE cells (n = 15–19). The average area is calculated using cells from five different embryos. Data represent mean ± SD, ****p < 0.0001. ns, non-significant. Scale bar: 50 µm.

Figure 2—source data 1.