Fig. 3. Assessment of placodal thickness and proliferation in Pax6^EE/EE mice. Wild-type (A) and Pax6^EE/EE (B) eyes at E9.5 in paraffin section. The numbered vertical lines indicate the points in the surface ectoderm at which the thickness of the lens placode was measured. Position 1 is on the nasal side and position 5 temporal. This was performed using digitized images and an arbitrary unit system. (C) Schematic of an E9.5 eye showing the section plane (purple shading) used for placodal thickness measurements. D, V, N and T indicate the dorsal, ventral, nasal and temporal aspects, respectively. (D) Graph showing, in arbitrary units, a comparison of placodal thickness in wild type (blue) Pax6^+/EE (green) and Pax6^EE/EE (red) embryos. This indicates that in approximately the nasal half of the lens placode, the Pax6^EE/EE placode is thinner than in wild type. The difference is greatest in the central placode and minimal in the temporal domain. Pax6^+/EE embryos have an intermediate phenotype. Vertical bars represent standard errors. Wild-type (E) and Pax6^EE/EE eyes (F) at E9.5 in paraffin section stained with Hoechst 33258 to indicate nuclei (green labeling) and with anti-BrdU detection reagents (red labeling). Only the green component of the blue Hoechst signal has been included in these images for ease of visualization. The percentage of BrdU-positive cells within the lens placode (white lines) was determined and presented in a histogram (G) comparing wild-type and Pax6^EE/EE embryos. This indicated that the level of proliferation was reduced in the Pax6^EE/EE lens placode. Vertical bars represent standard errors.

Return to article