Figure 3. Endplate morphology.

(A–D) Confocal images of prepatterned receptors in diaphragm of E14 embryos, visualized with Alexa-488-labeled α-bungarotoxin. (A) WT endplates and (B) γ/ε-fc endplates. AChRγ/ε-fc clusters are spread over a wider region and appear thinner than WT AChRγ (scale bar: 10 µm). (C, D) Higher resolution images (scale bar: 20 µm). (C) WT and (D) γ/ε-fc clusters have similar receptor densities. (E) Confocal images of single WT and γ/ε-fc endplates of E16 and E18 diaphragms visualized with Alexa-488-labeled α-bungarotoxin. E16 WT and γ/ε-fc endplates reveal no gross morphological differences. At E18, the WT endplate and the γ/ε-fc show morphological difference (scale bar: 10 µm). (F) Relative receptor densities measured as fluorescence intensities (see Material and Methods) are given in arbitrary units (a.u.). WT (white) and γ/ε-fc (gray) endplates at E16 and E18 (n = 60 endplates, 3 embryos per point). All data are represented as mean ± SEM). (G) Area (in µm²) of WT (white) and γ/ε-fc (gray) endplates at E16 and E18. n = 60 endplates, 3 embryos per point. All data are represented as mean ± SEM. (See also Figure S1).