Figure 4.

Ultrastructure of the apical processes of mouse RPE. Wild-type (A, D, and E), ashen (B and F), and shaker-1 (C and G) RPE were processed for transmission EM (A–D) or scanning EM (E–G). Several very thin apical processes can be seen between adjacent photoreceptor outer segments in wild-type, ashen, and shaker-1. The plasma membrane of the apical process becomes distended and distorted around the pigment granule (D). Scanning EM shows that apical processes are overlapping leaf-like projections in wild-type, ashen, and shaker-1. Bar, 500 nm (A–D); 2 μm (E–G).