|
Fig. 2. Most ionocytes develop in contact with ciliated cells. (A–F) Whole-mount co-immunostaining for xeel (A,D), acetylated α-tubulin (B,E) and v1a (A–C) or ca12 (D–F) in X. tropicalis tadpole epidermis shows that v1a-or ca12-expressing cells are neither goblet or ciliated cells but develop in close association with ciliated cells. High magnification of the area enclosed in a yellow box in B and E is shown in cross-section in C and F. v1a (C; green) shows close coupling with ciliated cells (C; red), whereas ca12 shows distinct basolateral staining in these transverse sections (F; green). The ca12-expressing cell (green) is also in direct contact with a ciliated cell (red). (G) Immunostaining of v1a (green) shows two distinct cell types. Approximately 30% of cells show bright apical staining corresponding to type 1 cells (highlighted with arrows), whereas the remaining v1a-expressing cells (type 2) show lateral membrane staining. (H,I) High magnification of type 1 and type 2 cells, respectively. (J) Cross-section of type 1 (arrow) and type 2 (arrowhead) v1a-expressing cells (green) shown adjacent to ciliated cells (red). (K–M) Co-immunostaining of ca12 (green) with v1a (red) shows colocalisation of these two markers in type 2 cells. Scale bars: 50 μm (A,B,D,E,G,K–M); 10 μm (C,F,H,I); 20 μm (J). |