Figure 3. Vax1 and Vax2 redundantly limit retinogenesis in the presumptive dorso-proximal and ventral RPE domains of the Mitf mutant optic cups.

(A–E) In E14.5 Mitf ^+/− heterozygotes, RPE defects are Vax1 and Vax2 gene dose-dependent. In the total absence of Mitf (F–I), VSX2 and PAX6 expression are seen in the ventral RPE regardless of whether only one copy of Vax2 (F,H) or one copy of Vax1 (G,I) is present. Also note that dorsal RPE thickening and VSX2 and PAX6 expression are more prominent when VAX2 is totally missing (G,I) as opposed to when VAX1 is totally missing (F,H). Scale bar: 200 µm (A–E); 130 µm (F–I). Coordinates in (A): D – dorsal; V – ventral; T – temporal; N – nasal.