Reduced FIZ1 concentration control: TEM-Immunogold of FIZ1 in the P-5 mouse neural retina. As a control comparator for P-35 retina (See Figure 1), P-5 retinal sections were processed simultaneously with P-35 retina samples. The lower concentration of FIZ1 in P-5 retina was below detection sensitivity in the GCL (A), the INL (B), and the C) ONL (photoreceptor progenitor nuclei). D) Immature Inner Segments (IS) are in contact with pigment granules (arrow) from the RPE. Outer Segments (OS) are not present at P-5.