Fig. 6. Pax6, Foxe3 and Sox2 are downregulated in Tfr7/Tfr7, Bmp7+/- mice. Immunohistochemical detection of Pax6 in the developing eyes of wild-type (A,C) Tfr7/Tfr7 (B,D) and Tfr7/Tfr7, Bmp7+/- (E) embryos at E9.5. In all cases, the lens placode is indicated by the arrowheads. Both the green and yellow colors show Pax6 immunoreactivity, but the yellow shows the peak signal intensity. A,B represent one experiment and indicate that there is a reduction in the level of Pax6 immunoreactivity in the lens placode of Tfr7/Tfr7 mice. The second experiment shows the lens placode at higher magnification and indicates that the level of Pax6 immunoreactivity is progressively reduced in Tfr7/Tfr7 (D) and Tfr7/Tfr7, Bmp7+/- (E) embryos. (F-H) Immunohistochemical detection of Pax6 in wild-type (F) Tfr7/Tfr7 (G) and Tfr7/Tfr7, Bmp7+/- (H) embryos at E10.5. The lens pit (lp) epithelium is demarcated by white arrowheads. pr, presumptive retina; rpe, presumptive retinal pigmented epithelium. These panels show that the lens pit is smaller and the per-cell Pax6 immunoreactivity lower in Tfr7/Tfr7 and Tfr7/Tfr7, Bmp7+/- mice. For experiments 1-3, Pax6 immunoreactivity in the presumptive retina (pr) is also reduced in Tfr7/Tfr7 (B,D,G) and Tfr7/Tfr7, Bmp7+/- (E,H) embryos compared with wild-type (A,C,F). (I-K) Whole-mount in situ hybridization with an antisense probe to Foxe3 in wild-type (I) Tfr7/Tfr7 (J) and Tfr7/Tfr7, Bmp7+/- (K) mice at E10.5. This shows that the level of Foxe3 expression is reduced in Tfr7/Tfr7, Bmp7+/- mice. The first branchial arch (1ba) is outlined in gray and the optic cup with a broken black line. (L-N) Thick sections of embryos hybridized with an antisense probe to Sox2 in wild-type (L) Tfr7/Tfr7 (M) and Tfr7/Tfr7, Bmp7+/- (N) mice at E10.5. This shows that Sox2 expression in the lens pit (lp and red arrowheads) cannot be detected in Tfr7/Tfr7 or Tfr7/Tfr7, Bmp7+/- mice.
