Fig. 3

CIROZ is expressed in the LRO of zebrafish, Xenopus, and mouse embryos (A) Whole-mount in situ hybridization (WISH) of ciroz in Danio rerio (zebrafish) embryos at indicated stages. The black arrow points to the expression in the Kupffer’s vesicle (KV). Scale bar, 0.25 mm. Similar results were obtained in at least three independent experiments with 50 embryos each. (B) WISH of ciroz in Xenopus laevis (frog) embryos at indicated stages. Colored dotted lines indicate the respective sections. Scale bar, 0.2 mm. c, central-flow-generating LRO cells; s, sensory LRO cells; end, lateral endodermal cells. Similar results were obtained in three independent experiments with at least 15 embryos each. (C) WISH of Ciroz in Mus musculus (mouse) embryos at indicated stages. Representative images of Ciroz expression are shown (n = 3 embryos per stage were stained). Whole embryos and zoomed-in pictures of the LRO are shown. Section in situ hybridization (SISH) of Nodal and Ciroz were performed on serial sections (purple dashed line) of late headfold embryos. Representative images are shown (n = 3 embryos). Section of a whole embryo with Nodal staining and zoomed-in pictures of the LRO for Nodal and a neighboring section for Ciroz are shown. The overlap image shows a false color merge of the picture of Nodal switched to red and Ciroz switched to green. Scale bars, 0.2 mm. V, ventral; D, dorsal; A, anterior; P, posterior; L, left; R, right; CBC, circumblastoporal collar; Pr, proximal; Di, distal; LRO, left-right organizer.