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*  Swap70b is required for convergent and extension cell movement during zebrafish gastrulation linking Wnt11 signalling and RhoA...
Swap70 functions as a guanine nucleotide exchange factor for Rac and RhoA regulating F-actin cytoskeletal rearrangements and playing a crucial role in mammalian cell activation, migration, adhesion and invasion. Here we show that the zebrafish orthologue, Swap70b, is required for convergent and extension cell movement during gastrulation. Swap70b morphants exhibited broader and shorter body axis but cell fate specification appeared normal. While ectopic Swap70b expression robustly rescued Wnt11 morphants, RhoA overexpression was sufficient to rescue Swap70b morphants, establishing Swap70b as a novel member of the non-canonical Wnt/PCP pathway downstream of Wnt11 and upstream of RhoA. This is distinct from the related Def6a protein that acts downstream of Wnt5b. Def6a/Swap70b morphants resemble Ppt/Slb double mutant embryos suggesting that Swap70b and Def6a delineate Wnt11 and Wnt5b signalling pathways.. ...
  http://eprints.nottingham.ac.uk/2917/
*  Mechanisms of early Drosophila mesoderm formation | Development
Several morphogenetic processes occur simultaneously during Drosophila gastrulation, including ventral furrow invagination to form the mesoderm, anterior and posterior midgut invagination to create the endoderm, and germ band extension. Mutations changing the behaviour of different parts of the embryo can be used to test the roles of different cell populations in gastrulation. Posterior midgut morphogenesis and germ band extension are partly independent, and neither depends on mesoderm formation, nor mesoderm formation on them. The invagination of the ventral furrow is caused by forces from within the prospective mesoderm (i. e. the invaginating cells) without any necessary contribution from other parts of the embryo. The events that lead to the cell shape changes mediating ventral furrow formation require the transcription of zygotic genes under the control of twist and snail. Such genes can be isolated by ...
  http://dev.biologists.org/content/116/Supplement/23
*  Regional requirements for Dishevelled signaling during Xenopus gastrulation: separable effects on blastopore closure,...
Gastrulation is the first major morphogenetic transformation in embryonic development. In the frog, the process of gastrulation must accomplish two major goals: the closure of the blastopore to bring the endoderm and mesoderm fully inside the ectoderm, and the generation of the archenteron. These end goals are accomplished through the concerted action of several different tissues, each of which engage in distinct cell movements and cell shape changes. The different tissues must require intricate coordination to ensure the successful completion of gastrulation. There are two separate challenges to resolve in frog gastrulation: identifying and understanding the cell and molecular events that take place in each of the different tissues (Keller et al., 2003), and discerning the mechanisms that coordinate these varied events between tissues.. Tissue isolation experiments have permitted the individual events to be studied in detail, and have ...
  http://dev.biologists.org/content/131/24/6195
*  Distinct Xenopus Nodal ligands sequentially induce mesendoderm and control gastrulation movements in parallel to the Wnt/PCP...
Gastrulation entails a set of morphogenetic processes that generate the external form of developing animals as well as the internal organisation of organ primordia. During the course of gastrulation, the precursors of the three germ layers, the endoderm, mesoderm and ectoderm, are repositioned from the surface of the blastula, such that at the end of this process the mesoderm is placed between the internal endoderm and the superficial ectoderm (Leptin, 2005; Solnica-Krezel, 2005). The germ-layer precursors are specified prior to gastrulation through a process called mesendoderm induction. In all vertebrate model systems, mesendoderm induction is a zygotic event that mobilises several signalling pathways, among which the Nodal family plays the most important part. Inhibition of Nodal activity by genetic mutation or expression of antimorphic constructs prevents mesendoderm specification in ...
  http://dev.biologists.org/content/137/3/417
*  The PDZ-GEF protein Dizzy regulates the establishment of adherens junctions required for ventral furrow formation in Drosophila...
When D'Arcy Wentworth Thompson's On Growth and Form was published 100 years ago, it raised the question of how biological forms arise during development and across evolution. In light of the advances in molecular and cellular biology since then, a succinct modern view of the question states: how do genes encode geometry? Our new special issue is packed with articles that use mathematical and physical approaches to gain insights into cell and tissue patterning, morphogenesis and dynamics, and that provide a physical framework to capture these processes operating across scales.. Read the Editorial by guest editors Thomas Lecuit and L. Mahadevan, as they provide a perspective on the influence of D'Arcy Thompson's work and an overview of the articles in this issue.. ...
  http://dev.biologists.org/content/139/22/e1.2
*  In vivo roles for Arp2/3 in cortical actin organization during C. elegans gastrulation | Journal of Cell Science
We have found that wild-type embryos form dynamic F-actin-rich structures specifically on mesodermal precursor cells during Ea/p cell internalization. These structures form transiently at the apical borders of MSap, MSpa and MSpp where they contact the internalizing Ea/p cells - sites consistent with where cell flattening had been seen previously by SEM (Nance and Priess, 2002) (Fig. 9). In Arp2/3-depleted embryos, cell fates, apicobasal cell polarity, myosin localization and myosin activation appeared normal, but plasma membrane association with the cell cortex was perturbed, and the F-actin-rich structures on MSxx cells were absent. Together with previous results (Severson et al., 2002), we conclude that Arp2/3 is required for completion of endoderm internalization in C. elegans. We speculate that the F-actin-rich structures lost in Arp2/3-depleted embryos might contribute to completion of ...
  http://jcs.biologists.org/content/122/21/3983
*  Gastrulations synonyms, gastrulations antonyms - FreeThesaurus.com
Synonyms for gastrulations in Free Thesaurus. Antonyms for gastrulations. 4 words related to gastrula: conceptus, fertilized egg, embryo, archenteron. What are synonyms for gastrulations?
  http://www.freethesaurus.com/gastrulations
*  Sdf1/Cxcr4 signaling controls the dorsal migration of endodermal cells during zebrafish gastrulation | Development
Vertebrate gastrulation starts with the internalization of mesodermal and endodermal cells, which establishes the internal and external organization of the developing animal (Solnica-Krezel, 2005). During internalization, the mesodermal and endodermal cells move via the blastopore beneath the ectoderm. It is well known that after internalization, the migration of mesodermal cells is controlled by convergence and extension (C&E) movements, which narrow the field of mesodermal cells mediolaterally and elongate it along the anterior-posterior axis (Myers et al., 2002; Montero and Heisenberg, 2004). Recent comprehensive studies in Xenopus and zebrafish have demonstrated that the Wnt/planar cell polarity (PCP) signaling pathway is implicated in C&E movements (Myers et al., 2002). The internalization of endoderm is coincident with that of mesoderm and, after its ...
  http://dev.biologists.org/content/135/15/2521
*  Gastrulation, Gastrulation The end of cleavage of the unicellular zygote results in, Biology
Biology Assignment Help, Gastrulation, Gastrulation The end of cleavage of the unicellular zygote results in the creation of multicellular blastula, which may be a solid structure with no a cavity (stereoblastula), or its cells might be arranged in the form of a one cell or several
  http://www.expertsmind.com/questions/gastrulation-30130169.aspx
*  "Regulation of Epithelial Morphogenesis by β-Arrestin Kurtz" by Katarzyna Maria Piotrowska
Arrestins are ubiquitous adaptor proteins that are implicated in diverse signaling pathways. Arrestins are involved in the regulation of G-protein coupled receptors (GPCRs) via endocytosis and desensitization followed by degradation or recycling of the receptor. There are two β-arrestin homologs in mammals, which are largely redundant and therefore difficult to study. Drosophila has a single β-arrestin, Kurtz (Krz), and hence presents unique opportunities to study the functions of β-arrestin. krz maternal mutants have been shown to cause defects in the gastrulation of Drosophila embryos. These were attributed to effects of Krz on Toll signaling pathway. To investigate the origins of the defects, the early hours of embryo development needed to be examined. One of the main pathways activated during the first hours of gastrulation that enables epithelial remodeling and ventral furrow formation is Fog-Mist signaling. Mist is a GPCR that is activated by Fog, which triggers a ...
  https://scholarworks.umb.edu/masters_theses/330/
*  Distinct functions of the major Fgf8 spliceform, Fgf8b, before and during mouse gastrulation
Development. 2007 Jun;134(12):2251-60. Guo Q, Li JY.. The vertebrate Fgf8 gene produces multiple protein isoforms by alternative splicing. Two evolutionarily conserved spliceforms, Fgf8a and Fgf8b, exhibit distinct bioactivities, with Fgf8b having a more potent inductive activity due to higher affinity for Fgf receptors. To investigate the in vivo requirement for Fgf8b, we created a splice-site mutation abolishing Fgf8b expression in mice. Analysis of this mutant has uncovered a novel function of Fgf8 signaling before the onset of gastrulation. We show that the loss of Fgf8b disrupts the induction of the brachyury gene in the pregastrular embryo and, in addition, disrupts the proper alignment of the anteroposterior axis with the shape of the embryo and the uterine axes at embryonic day (E) 6.5. Importantly, Fgf8-null embryos display the same phenotype as Fgf8b-deficient embryos at E6.5, demonstrating that signaling by Fgf8b is specifically required for development of the pregastrular embryo. ...
  https://dloale.wordpress.com/2007/06/12/distinct-functions-of-the-major-fgf8-spliceform-fgf8b-before-and-during-mouse-gastrulation/
*  Epiboly - mechanism of gastrulation, Biology
Biology Assignment Help, Epiboly - mechanism of gastrulation, EPIBOLY - The epibolic movements occur only in the prospective ectodermal blastomeres. In the blastula of frog, migration and rearrangement of microceres over megameres is called epiboly. At one specific point micromeres do not cover meg
  http://www.expertsmind.com/questions/epiboly-mechanism-of-gastrulation-30115995.aspx
*  PDGF-A controls mesoderm cell orientation and radial intercalation during Xenopus gastrulation | Development
To analyze the arrangement of its cells, the dorsal mesoderm was divided into three regions. Expression of Xenopus brachyury (Xbra) demarcates the chordamesoderm, and goosecoid (gsc) the PCM (Fig. 1D,F′-G′) (Wilkinson et al., 1990; Cho et al., 1991). The leading edge mesendoderm (LEM) was defined as the region between the anterior boundary of gsc expression and the leading edge (Fig. 1D,E); it expresses cerberus (cer) (Fig. 1E-E′) (Bouwmeester et al., 1996). In order to determine the extent of the xBra and gsc regions on SEM micrographs, the length and width of these expression domains relative to total mesoderm size was determined from images of in situ hybridization experiments (see Fig. S1 in the supplementary material).. In the LEM, cell shapes and sizes varied, but all cells exhibited a distinct polarity with a single protrusion-bearing pole. Cells were oriented obliquely with respect to the BCR (Fig. ...
  http://dev.biologists.org/content/138/3/565?iss=14
*  The many functions of Cyr61 | Development
The proper execution of gastrulation requires that cell signalling, cell adhesion and cell migration are all precisely coordinated and integrated. In their investigations into how this might occur, Latinkic et al. studied Cyr61, a CCN-family, secreted, extracellular matrix (ECM)- associated protein. CCN proteins are very versatile - they can mediate cell adhesion and migration, for example, and can induce signalling events - all expected features of candidate gastrulation regulators. The authors now report, on p. 2429, that Cyr61 is an important regulator of gastrulation movements: both its overexpression and inhibition disrupt gastrulation in frog embryos, perhaps because Cyr61 is required for the assembly of a fibronectin-rich ECM and because it regulates cell- cell and cell-matrix adhesion. Intriguingly, Xcyr61 also appears to both stimulate and inhibit Wnt signalling in a context-dependent manner. Future studies into the different ...
  http://dev.biologists.org/content/130/11/e1104
*  Iris View Profile
I am interested in cellular and molecular mechanisms underlying co-ordinated and directional cell movements. The primary focus is on morphogenetic movements occurring during gastrualtion using the zebrafish as a model system; epiboly, convergence/extension and anterior migration of mesodermal cells. Since we showed that Wnt11 is an important regulator of convergence/extension movements during gastrulation in vertebrates, it has been evident that this ligand acts in a pathway related to the planar cell polarity (PCP) pathway in Drosophila. Recently, the core PCP genes have been also implicated in regulating a variety of morphogenetic processes in vertebrates including neural tube closure, orientation of cochlear hair cells, migration of facial motorneurons and ciliogenesis. Current projects are a) Understanding mechanisms by which core PCP proteins regulate gastrulation movements in zebrafish; b) Identifying ...
  http://iris.ucl.ac.uk/iris/browse/profile?upi=MTADA04
*  Distinct functions of the major Fgf8 spliceform, Fgf8b, before and during mouse gastrulation | Development
When D'Arcy Wentworth Thompson's On Growth and Form was published 100 years ago, it raised the question of how biological forms arise during development and across evolution. In light of the advances in molecular and cellular biology since then, a succinct modern view of the question states: how do genes encode geometry? Our new special issue is packed with articles that use mathematical and physical approaches to gain insights into cell and tissue patterning, morphogenesis and dynamics, and that provide a physical framework to capture these processes operating across scales.. Read the Editorial by guest editors Thomas Lecuit and L. Mahadevan, as they provide a perspective on the influence of D'Arcy Thompson's work and an overview of the articles in this issue.. ...
  http://dev.biologists.org/content/early/2007/05/16/dev.004929
*  Negative regulation of Activin/Nodal signaling by SRF during Xenopus gastrulation | Development
In the Xenopus early embryo, the mesodermal cell fate is established in the marginal zone between the animal and vegetal poles by inductive signals from the underlying endoderm. This induction cooperates with the independent patterning signals from the organizer to define the dorsoventral and anteroposterior pattern of the body axis (Harland and Gerhart, 1997; Heasman, 2006). Several members of the TGF-β growth factor superfamily, including Activin, Vg1 and Nodal-related proteins are responsible for the induction of mesoderm and endoderm germ layers as well as for the subsequent patterning of the embryo (Schier, 2003). These ligands bind to a serine-threonine kinase receptor complex leading, intracellularly, to the phosphorylation and activation of the receptor-Smad family of signal transducers (R-Smads) that includes Smad2 and Smad3. Upon activation, these R-Smads translocate into the nucleus where they control gene expression in association with Smad4 and certain ...
  http://dev.biologists.org/content/134/4/769
*  Gene Expression Literature Detail
J:165751 Du J, Takeuchi H, Leonhard-Melief C, Shroyer KR, Dlugosz M, Haltiwanger RS, Holdener BC, O-fucosylation of thrombospondin type 1 repeats restricts epithelial to mesenchymal transition (EMT) and maintains epiblast pluripotency during mouse gastrulation. Dev Biol. 2010 Oct 1;346(1):25-38 ...
  http://www.informatics.jax.org/gxdlit/key/116487
*  Gastrulation - Everything2.com
A process during early embryonic development in animals in which large-scale cell migration occurs and different cell types emerge to form the germ laye...
  https://everything2.com/title/Gastrulation
*  A Crumby affair: Cell ingression during gastrulation - the Node
Comment on 'Crumbs2 promotes cell ingression during the epithelial-to-mesenchymal transition at gastrulation' Ramkumar N, Omelchenko T, Silva-Gagliardi NF,
  http://thenode.biologists.com/crumby-affair-cell-ingression-gastrulation/research/
*  Bio Sci 93: DNA to Organisms. Lec. 26: Gastrulation and Organogenesis :: UC Irvine, UCI Open
Recorded: November 30, 2012Terms of Use: http://open.uci.edu/info.Course Description: Cell biology, biochemistry, genetics, and the biology...
  http://ocw.uci.edu/lectures/bio_sci_93_dna_to_organisms_lec_26_gastrulation_and_organogenesis.html
*  Andreia Bernardo, PhD
I am interested in understanding the molecular events that coordinate early gastrulation and placental development. In particular, I would like to determine the roles and mechanism of action of specific transcription factors, which seem to play roles both in mesoderm and in placental specification. One of such genes is CDX2, which I have recently demonstrated to be a downstream target of BRACYURY in hESCs, and thus to represent an early mesoderm marker in BMP-treated hESCs. I would now like to determine how CDX2 induces a mesodermal program in one context and a placental program in the other context.. Funding: EU Plurisys. ...
  https://www.trophoblast.cam.ac.uk/people/andreia-bernardo
*  Gene Expression Literature Detail
J:157256 Powers SE, Taniguchi K, Yen W, Melhuish TA, Shen J, Walsh CA, Sutherland AE, Wotton D, Tgif1 and Tgif2 regulate Nodal signaling and are required for gastrulation. Development. 2010 Jan;137(2):249-59 ...
  http://www.informatics.jax.org/gxdlit/key/101982
*  Life: In The Making… Embryology | Science Defined
This is a video of zebrafish going through the most important portion of development, gastrulation, and then seemingly having a massive fit (they are probably just starting to move about, the films sped up a lot so it looks a bit odd). It's a little bit crazy that we can see something like this happening right…
  https://sciencedefined.wordpress.com/2012/01/19/life-in-the-making-embryology/
*  Gene Expression Literature Detail
J:173627 Billington CJ Jr, Ng B, Forsman C, Schmidt B, Bagchi A, Symer DE, Schotta G, Gopalakrishnan R, Sarver AL, Petryk A, The molecular and cellular basis of variable craniofacial phenotypes and their genetic rescue in Twisted gastrulation mutant mice. Dev Biol. 2011 Jul 1;355(1):21-31 ...
  http://www.informatics.jax.org/gxdlit/key/130594