Fig. 1.

Blimp1 expression in the developing mouse retina. (A) E12 retina stained for Blimp1 (green in all panels) and Otx2 (red). All Blimp1⁺ cells express Otx2 (arrow). Otx2 also labels the pigmented epithelium (asterisk). Blimp1 is also seen in vascular endothelial cells in the vitreous (arrowhead, as also in E,F). (B-F) E14.5 retinas stained for Blimp1. (B) All Blimp1⁺ cells co-express Otx2 (red) (arrow), but not all Otx2⁺ cells express Blimp1. (C) All Crx⁺ cells (red) co-express Blimp1, but not all Blimp1⁺ cells express Crx. (D) Few Blimp1⁺ cells co-express Sox9⁺ (red), a progenitor marker. (E) All Blimp1⁺ cells express NeuroD1 (red) (arrow), but not all NeuroD1⁺ cells express Blimp1. (F) All Trβ2⁺ cones express Blimp1. (G) At P0, all Blimp1⁺ cells co-express Otx2 (red). (H) At P4, Blimp1⁺ cells cover a large domain and many recoverin-labeled photoreceptors (red) co-express Blimp1 (arrow). (I) At P6, Blimp1 is seen only in the peripheral retina. Many recoverin-labeled (red) photoreceptors co-express Blimp1 (arrow). (J) Relative Blimp1 mRNA expression normalized to the E12.5 value. Shown are six measurements for each time-point; the bar represents the average. Expression starts at ∼E12 and is not seen in adult retina. Scale bars: 50 μm, except 10 μm for insets.