Figure 4.

Differential distribution of M and S opsins in Nrl^b2/b2 and Nrl^−/− mice. A, In situ hybridization analysis of cone opsin and rhodopsin mRNA in superior and inferior retinal regions in 8-week-old mice. Nrl^b2/b2 mice overexpressed M and S opsins with a normal distribution trend, whereas in Nrl^−/− mice, S opsin was strongly overexpressed in all retinal regions. Nrl^−/− mice showed a small increase in the density of M opsin-positive cells in superior regions compared with +/+ mice, partly due to ONL folding in Nrl^−/− mice. B, In situ hybridization analysis of opsin mRNA in hypothyroid Nrl^b2/b2 mice at P17. On a hypothyroid Tshr^−/− background, M opsin expression was retarded and S opsin overexpression exacerbated in Nrl^b2/b2 mice. Scale bar: A (for A, B), 50 μm. C, Diagram of mouse eye section indicating location of superior and inferior retinal fields examined (boxes). Gray triangles, Retinal pigmented epithelium.