Figure 3

Cornea morphogenesis. Diagram of embryonic (A) and adult (F) zebrafish corneas. Morphology of embryonic (B-E) and adult corneas (G-K). Histology of cornea and anterior lens of 3 dpf embryo (B). TEM micrograph showing embryonic cornea epithelium, CE; cornea stroma, CS; and cornea endothelium, CN (C). In this panel, the lens epithelium (Lens EP) is indicated by blue shading. High magnification insets of developing cornea stroma (D) and "scalloped" cornea epithelium of 3 dpf embryo (E). Histology of cornea and anterior lens of 1 month adult (G). TEM micrograph showing 1 month cornea epithelium, cornea stroma, and cornea endothelium (H). Extensive interdigitation between epithelial cells is indicated with arrows (H). High magnification insets of the mature cornea epithelial cells (I), cornea sub-epithelial cells (J), and cornea stroma and endothelium (K). Note the increase of electron dense cell junctions in cornea sub-epithelial cells (J) and the establishment of a flattened layer of cells, indicated with asterisk, between the stroma and endothelium (K). In both the developing and mature cornea stroma, orthogonally arranged collagen fibrils are clearly visible and the stromal thickness has increased with development (D and K).