FIGURE 1

FIGURE 1

Dorsal forerunner cells give rise to the ciliated Kupffer’s vesicle that functions as the left-right organizer in the zebrafish embryo. (A) Diagram of early zebrafish embryo development. Dorsal forerunner cells (DFCs) are specified at the 50% epiboly stage and then form Kupffer’s vesicle (KV) by the 6 somite stage at 12 h post-fertilization (hpf). Cilia-generated fluid flow inside KV directs asymmetric expression of spaw and downstream asymmetric heart development. For all pharmacological treatments herein, drugs were added to embryos at the 60% epiboly stage (6.5 hpf) and removed at 70% epiboly (7.5 hpf). Created using BioRender.com. (B) Confocal microscopy images of DFCs and the ciliated KV. DFC/KV cells are labeled with membrane-localized EGFP expression in Tg(sox17:EGFP-caax) embryos. KV cilia are labeled with anti-acetylated tubulin antibodies. (C) RNA in situ hybridization of spaw expression in left lateral plate mesoderm (arrow) in a wild-type embryo. Dashed line marks the embryo midline. (D) Left-sided jogging (dashed arrow) of the heart visualized by EGFP expression driven by a myl7 promoter in cardiomyocytes in a wild-type embryo.