Fig. 5

Mutations of PIH genes caused abnormal motilities of Kupffer’s vesicle cilia.

(A) Images of zebrafish embryo and Kupffer's vesicle. Red square in left-hand image indicates the position of the Kupffer's vesicle in a 12 hpf embryo. Right-hand image shows the dorsal view of the Kupffer's vesicle. (B) Diagram of zebrafish Kupffer's vesicle. Mono-cilia, which project from epithelial cells, have rotational motilities to produce left-ward fluid flow (red arrow) in the organ. (C) Typical kymographs of Kupffer’s vesicle cilia in WT and PIH gene mutants. Patterns of the kymographs were categorized into three classes: rotating (blue), irregular (green), and immotile (red). (D) Ratios of each motility class. Number of observed cilia: WT, 76; pih1d1^-/-, 67; pih1d2^-/-, 198; ktu^-/-, 190; twister^-/-, 53; and pih1d2^-/-;ktu^-/-, 48. (E) Rotational frequencies of Kupffer’s vesicle cilia. Bar graphs show mean ±SD. **: p-value<0.01 in Dunnett's test of each mutant against WT. (F) Heart looping of WT and mutant embryos at 30 hpf. Number of samples: WT, 247; pih1d1^-/-, 288; pih1d2^-/-, 275; ktu^-/-, 285; twister^-/-, 139; and pih1d2^-/-;ktu^-/-, 276. (G) Diagram represents normal heart looping of the 30 hpf embryo. V, ventricle; A, atrium.