Vertebrate embryonic patterning depends on signaling from Nodal, a TGFβ superfamily member. There are three Nodal orthologs in zebrafish; southpaw directs left-right asymmetries, while squint and cyclops function earlier to pattern mesendoderm. TGFβ member Vg1 is implicated in mesoderm formation but the role of the zebrafish ortholog, Growth differentiation factor 3 (Gdf3), has not been fully explored. We show that zygotic expression of gdf3 is dispensable for embryonic development, while maternally deposited gdf3 is required for mesendoderm formation and dorsal-ventral patterning. We further show that Gdf3 can affect left-right patterning at multiple stages, including proper development of regional cell morphology in Kupffer's vesicle and the establishment of southpaw expression in the lateral plate mesoderm. Collectively, our data indicate that gdf3 is critical for robust Nodal signaling at multiple stages in zebrafish embryonic development.

脊椎动物的胚胎模式取决于来自TGFβ超家族成员Nodal的信号传导。斑马鱼中有3个Nodal直系同源物。Southpaw引导左右不对称，而斜眼和独眼巨人则更早地发挥作用来塑造中胚层。TGFβ成员Vg1参与中胚层的形成，但尚未充分探讨斑马鱼直系同源物生长分化因子3（Gdf3）的作用。我们表明，gdf3的合子表达对于胚胎发育是必不可少的，而母体沉积的gdf3是中胚层形成和背-腹图案形成所必需的。我们进一步表明，Gdf3可以在多个阶段影响左右模式，包括在Kupffer囊泡中区域细胞形态的正确发育以及在侧板中胚层中建立Southpaw表达。总体而言，我们的数据表明gdf3对于斑马鱼胚胎发育的多个阶段中的强大Nodal信号传导至关重要。