... of the actin-severing and depolymerization machinery during vertebrate gastrulation, with a focus on Twinfilin1 (Twf1) in Xenopus . We find that Twf1 is essential for convergent extension, and loss of Twf1 results in a disruption of lamellipodial dynamics and polarity. Moreover, Twf1 loss results in a failure...

..., and the definitive endoderm that forms later, at gastrulation, as one of the germ layers of the embryo proper. Fate mapping evidence suggests that the definitive endoderm arises as two waves, which potentially reflect two distinct cell populations. Early primitive ectoderm-like (EPL) cell differentiation has been...

... 2014. Published by The Company of Biologists Ltd 2014 Drosophila Gastrulation Cell adhesion β-catenin Wingless signalling The organisation and dynamics of many tissues in multicellular animals rely on cell–cell adhesion mediated by the conserved cadherin superfamily of transmembrane...

... to continue after the epithelial-to-mesenchymal transition, as overexpression of Dzy or of constitutively active Rap1 compromises mesodermal migration and monolayer formation. We propose that Dzy and Rap1 are crucial factors regulating the dynamics of AJs during gastrulation. * Author...

... remain undefined. Here, the establishment of PCP must be coordinated with dynamic changes in cell adhesion and extracellular matrix (ECM) organization. During gastrulation, the membrane type-1 matrix metalloproteinase (MT1-MMP or MMP14) is required for PCP and convergence and extension cell movements. We...

... mesoderm and uncovers a permissive role for non-canonical Wnt-signaling, myosin contractility and F-actin polymerization in regulating these dynamics. * Author for correspondence ( [email protected] ) 20 10 2010 © 2011. 2011 Morphogenesis Gastrulation Mediolateral cell intercalation...

... tissues, although it is enriched in neural structures. δ-catenin associates with classical cadherins, with crude embryo fractionations further revealing non-plasma-membrane pools that might be involved in cytoplasmic and/or nuclear functions. Depletion of δ-catenin caused gastrulation defects, phenotypes...

... embryo. In C. elegans , the first morphogenetic movement, gastrulation, is initiated by the internalization of two endodermal precursor cells. These cells undergo a myosin-dependent apical constriction, pulling a ring of six neighboring cells into a gap left behind on the ventral surface of the embryo...

...Vinzenz Link; Lara Carvalho; Irinka Castanon; Petra Stockinger; Andrej Shevchenko; Carl-Philipp Heisenberg During vertebrate gastrulation, a well-orchestrated series of morphogenetic changes leads to the formation of the three germ layers: the ectoderm, mesoderm and endoderm. The analysis of gene...

...Pierre-Henri Puech; Anna Taubenberger; Florian Ulrich; Michael Krieg; Daniel J. Muller; Carl-Philipp Heisenberg During vertebrate gastrulation, progenitor cells of different germ layers acquire specific adhesive properties that contribute to germ layer formation and separation. Wnt signals have...

... in this region prevents closure of the blastopore during gastrulation. We conclude that Ral signalling is autonomously required by mesodermal cells to effect essential morphogenetic changes during Xenopus gastrulation. Animal caps were observed using a Leica TCS-4D confocal imaging system (Leica Instruments...

...Hiroki Oda; Shoichiro Tsukita ABSTRACT Invagination of the epithelial cell sheet of the prospective mesoderm in Drosophila gastrulation is a well-studied, relatively simple morphogenetic event that results from dynamic cell shape changes and cell movements. However, these cell behaviors have...

...Kristina L. Straub; Maria Cristina Stella; Maria Leptin ABSTRACT We have analysed the developmental defects in Drosophila embryos lacking a gelsolin-related protein encoded by the gene flightless I . Such embryos have previously been reported to gastrulate abnormally. We now show that the most...

...E. J. Sanders; S. Prasad ABSTRACT We have examined the immunocytochemical distribution of TGFβ1 (transforming growth factor β 1) in the gastrulating chick embryo, and have correlated the results with the ability of this factor to promote in vitro changes in the phenotype of mesoderm and epiblast...

...A. J. Brown; E. J. Sanders ABSTRACT In the gastrulating chick embryo, the mesoderm cells arise from the epiblast layer by ingression through the linear accumulation of cells called the primitive streak. The mesoderm cells emerge from the streak with a fibroblastic morphology and proceed to move...

...E. J. Sanders ABSTRACT An investigation has been made into some of the possible mechanisms underlying the invasionary activity of gastrulating cells at the primitive streak of the early chick embryo. At gastrulation, epithelial cells in the upper epiblast layer of the embryo undergo...

...E. J. Sanders; S. Prasad ABSTRACT At the time of gastrulation in the chick embryo the upper epiblast layer penetrates its own basement membrane at the primitive streak so that its cells may invade the underlying tissue space. In so forming the primary mesoderm, the cells undergo a concomitant...

...E. J. Sanders; P. Chokka ABSTRACT Chick embryos in culture were treated with the secretion-inhibiting ionophore monensin at the gastrulation stage of development. After treatment for 5h at a concentration of 10 −5 M the embryos showed a drastic reduction in the tissue space between the upper...

...Norio Nakatsuji ABSTRACT During amphibian gastrulation, presumptive mesoderm cells migrate from the blastopore towards the animal pole along the inner surface of the ectodermal layer. Their natural substratum is a network of anastomosing extracellular matrix fibrils, which contains fibronectin...

...Jean-François Riou; Thierry Darribère; Jean-Claude Boucaut ABSTRACT Identification of the cell surface glycoproteins is an essential requirement for elucidating the mechanisms that mediate intercellular adhesion and cell migration in gastrulating amphibian embryos. In our experiments...