Fig. 1. Loss of Cdh2 affects kinocilia and cellular microtubule networks. Panels A and B are transverse sections tilted to include both the anterior and posterior maculae in the same view of 48 hpf embryos labeled with anti-Cdh2 antibody. In control embryos the anterior (am) and posterior maculae (pm), are strongly labeled by Cdh2 (A). Cdh2 immunolabeling of sensory patches in cdh2 MO-injected embryos is absent (B). Panels C and D are image volumes acquired by two-photon microscopy of 48 hour post-fertilization whole-mount zebrafish stained using anti-ß-catenin. Projections are 6 µm optical sections of a lateral view of the regions containing the anterior and posterior maculae (am and pm) in a control (C) and in a cdh2 MO-injected embryo. Rostral is left, dorsal is up and ventral is down. Panels E, F are projections of two optical sections through the anterior maculae of 120 hpf embryos labeled with anti-acetylated-tubulin (shown in green) to visualize kinocilia and Texas-Red-conjugated phalloidin (shown in white) to visualize hair cell sterociliary bundles. Well-formed kinocilia are present in hair cell bundles in control embryos (E), but reduced in cdh2 MO-injected embryos. This is especially evident in the insets in panels E and F, showing images of acetylated-tubulin-labeled posterior maculae from 48 hpf embryos using DAB/peroxidase detection (bottom insets), and a larger rendered volume from the image stack used to make panels E and F (upper inset; this volume can be viewed as rotating, three-dimensional rendered volumes in Movies 1 and 2, see supplementary material). Ciliary bundles in control embryos each correspond to a kinocilium. In cdh2 MO-injected embryos, hair cell bundles are associated with short kinocilia, or kinocilia are absent. Abbreviations: h, hindbrain. Bars: A-D, 50 µm; E-F, 10 µm.