...Zhonghui Fei; Koeun Bae; Serge E. Parent; Haoyu Wan; Katharine Goodwin; Ulrike Theisen; Guy Tanentzapf; Ashley E. E. Bruce ABSTRACT In teleost fish, the multinucleate yolk syncytial layer functions as an extra-embryonic signaling center to pattern mesendoderm, coordinate morphogenesis and supply...

...James A. Gagnon; Kamal Obbad; Alexander F. Schier ABSTRACT The role of the zebrafish transcription factor Nanog has been controversial. It has been suggested that Nanog is primarily required for the proper formation of the extra-embryonic yolk syncytial layer (YSL) and only indirectly regulates...

... and the relative contributions of Nodal-related ligands from embryonic, extraembryonic and maternal sources remain uncertain. In zebrafish, signals from the yolk syncytial layer (YSL), an extraembryonic domain, are required for mesoderm and endoderm induction, and YSL expression of nodal-related 1 ( ndr1...

... is known about signals from surrounding cells and tissues controlling these movements. Here, we show that, in gastrulating zebrafish embryos, convergence movements of nuclei within the yolk syncytial layer (YSL) are guided by mesoderm and endoderm progenitors migrating along the surface of the yolk towards...

...Shaw-Ree Chen; David Kimelman ABSTRACT Formation of the three germ layers requires a series of inductive events during early embryogenesis. Studies in zebrafish indicate that the source of these inductive signals may be the extra-embryonic yolk syncytial layer (YSL). The characterization of genes...

... of the external yolk syncytial layer. This causes narrowing of the E-YSL and initiates the epibolic expansion of the blastoderm. Convergent movements of deep cells within the blastoderm begin toward the end of this contraction. The YSL forms as a result of invasion of the yolk cell cytoplasm by nuclei from open...