Figure 4. Disc incisures are observed in mature but not newly forming discs.
(A) Representative z-sections at the depths of 0 (left),+168 (middle) and +244 nm (right) from a reconstructed electron tomogram of a 750 nm-thick WT mouse retinal section. Full tomogram is shown in Figure 4—video 1. To guide the reader, the surfaces of newly forming discs are pseudo-colored in orange and a mature disc in magenta. Pseudo-coloring was used only in this example as it masks some fine morphological features of the images. (B) Representative z-sections at the depths of 0 (left),+107 (middle) and +343 nm (right) from the reconstructed electron tomogram shown in Figure 4—video 2. (C) Representative z-sections at the depths of 0 (left),+65 (middle) and +186 nm (right) from the reconstructed electron tomogram shown in Figure 4—video 3. (D) Representative z-sections at the depths of 0 (left),+19 (middle) and +208 nm from the reconstructed electron tomogram shown in Figure 4—video 4. Yellow asterisks indicate the ciliary axoneme; yellow arrows point to newly forming, unenclosed discs; yellow arrowheads point to incisures in fully enclosed discs. Tomogram pixel size is 4.2 nm (A) or 2.1 nm (B–D); scale bar: 0.5 µm.
