... into the role of microtubules in morphogenesis of an extra-embryonic tissue and further contributes to the understanding of nuclear migration mechanisms during development. Epiboly is a major cell movement during teleost gastrulation in which the blastoderm and the YSL spread vegetally to engulf the yolk cell...

... nanog (maternal and zygotic null) mutant zebrafish embryos . Without functional Nanog, epiboly is severely affected, embryo axes do not form and massive cell death starts at the end of gastrulation. We show that three independent defects in MZ nanog mutants contribute to epiboly failure: yolk...

.... Expression of FF in the animal cap revealed a previously unidentified role of FAK in early morphogenesis and specifically epiboly. We show that a fibronectin-derived signal transduced by FAK governs polarity and cell intercalation. Finally, failure of epiboly results in severe gastrulation problems that can...

... to initiate epiboly, which can be rescued by re-expression of 2-OST protein. Reduced cell adhesion and altered cell cycle regulation in 2-OST-deficient embryos are associated with decreased β-catenin and E-cadherin protein levels at cell junctions, and these defects can be rescued by reactivation...

... that drive epiboly in early Danio rerio (zebrafish) development. We show that depletion of αE-catenin caused a defect in radial intercalation that was associated with decreased cell-cell adhesion, in a similar manner to E-cadherin depletion. Depletion of αE-catenin also caused deep cells to have protracted...

...Filipa Carreira-Barbosa; Mihiko Kajita; Veronique Morel; Hironori Wada; Hitoshi Okamoto; Alfonso Martinez Arias; Yasuyuki Fujita; Stephen W. Wilson; Masazumi Tada During vertebrate gastrulation, the body axis is established by coordinated and directional movements of cells that include epiboly...

... an embryo at 50%epiboly shows that presumptive DFCs (asterisks) are partially positioned underneath the EVL (A). Clear enrichment of aPKC-ζ is found at the contact point between one of the DFCs and the overlying EVL (A,A′;arrowheads). At 75% epiboly, the EVL completely covers the DFCs (B). A sagittal...

... maternally and in restricted cell types zygotically. Knockdown of amotl2 expression delays epiboly and impairs convergence and extension movement, and amotl2-deficient cells in mosaic embryos fail to migrate properly. This coincides with loss of membrane protrusions and disorder of F-actin. Amotl2 partially...

..., a blastoderm-specific arrest of epiboly. Dorsal tissues expand to the ventral side at the expense of ventrolateral tissue in MZ spg embryos. Dorsally expressed Bmp-antagonists, such as Chd and Nog1, and Gsc are ectopically activated at ventral levels in MZ spg . Lack of ventral specification is apparent very...

... that FAM53B bound 14-3-3 chaperones, as well as SKIIP proteins, adaptor proteins connecting DNA-binding proteins to modulators of transcription. smp inactivation with morpholinos led to delayed epiboly and reduced embryonic size. Absence of Smp activity did not induce apoptosis, but resulted in a reduced cell...

...Donald A. Kane; Karen N. McFarland; Rachel M. Warga Epiboly, the spreading of the blastoderm over the large yolk cell, is the first morphogenetic movement of the teleost embryo. Examining this movement as a paradigm of vertebrate morphogenesis, we have focused on the epiboly arrest mutant half...

... limited to the axial mesoderm and is transient, observed only during the gastrula period. Later, after epiboly is completed, convergence of the domain in the mutant begins at a rapid rate, and the domain width becomes similar to that of the WT notochord by the three-somite stage. It may...

... gastrulae injected with monoclonal antibodies directed against the central cell-binding domain of fibronectin. Among the defects observed is a disruption of fibronectin matrix assembly, resulting in a failure of radial intercalation movements, which are required for blastocoel roof thinning and epiboly. We...

...Ellen M. Williams-Masson; Amy N. Malik; Jeff Hardin ABSTRACT The epiboly of the Caenorhabditis elegans hypodermis involves the bilateral spreading of a thin epithelial sheet from the dorsal side around the embryo to meet at the ventral midline in a process known as ventral enclosure. We present...

... ABSTRACT Epiboly, the enveloping of the yolk cell by the blastoderm, is the first zebrafish morphogenetic movement. We isolated four mutations that affect epiboly: half baked, avalanche, lawine and weg . Homozygous mutant embryos arrest the vegetal progress of the deep cells of the blastoderm; only...

... signaling pathway, respectively. Mutations in the third group affect primarily cellular rearrangements during gastrulation and have complex effects on cell fates in the embryo. This group, and to some extent mutations from the first two groups, affect the major morphogenetic processes, epiboly, convergence...

... and the germinal bands to these cell movements. Here we describe cellular events during epiboly in normal embryos and in embryos perturbed by either reducing the number of cells in the epithelium, or by preventing the formation of the germinal bands, or both. These experiments indicate that both the germinal bands...

... into the dorsal animal cap region as the dorsal clones recede. At stage 10, the ventral animal clones extend across the entire dorsal animal cap. These changes in the blastomere constituents of the animal cap during epiboly may contribute to the changing capacity of the cap to respond to inductive growth factors...

... of Biologists 1993 branchial arches Brachydanio rerio epiboly gastrulation mesoderm neural crest no tail paraxial mesoderm snail1 somitogenesis spadetail zebrafish zinc finger Gastrulation in a variety of organisms is a critical event that leads to the formation of the three...

...Uwe Strähle; Suresh Jesuthasan ABSTRACT Early morphogenesis of the teleost embryo is characterized by three orchestrated cell movements. Epiboly leads to spreading of the blastoderm over an uncleaved yolk cell while involution around the blastoderm margin and convergence movements towards...