Academic literature on the topic 'Neurectoderm'
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Journal articles on the topic "Neurectoderm"
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Rathjen, Joy, Bryan P. Haines, Kathryn M. Hudson, Antonietta Nesci, Stephanie Dunn, and Peter D. Rathjen. "Directed differentiation of pluripotent cells to neural lineages: homogeneous formation and differentiation of a neurectoderm population." Development 129, no. 11 (June 1, 2002): 2649–61. http://dx.doi.org/10.1242/dev.129.11.2649.
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During embryogenesis the central and peripheral nervous systems arise from a neural precursor population, neurectoderm, formed during gastrulation. We demonstrate the differentiation of mouse embryonic stem cells to neurectoderm in culture, in a manner which recapitulates embryogenesis, with the sequential and homogeneous formation of primitive ectoderm, neural plate and neural tube. Formation of neurectoderm occurs in the absence of extraembryonic endoderm or mesoderm and results in a stratified epithelium of cells with morphology, gene expression and differentiation potential consistent with positionally unspecified neural tube. Differentiation of this population to homogeneous populations of neural crest or glia was also achieved. Neurectoderm formation in culture allows elucidation of signals involved in neural specification and generation of implantable cell populations for therapeutic use.
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Morgan, R., and M. G. Sargent. "The role in neural patterning of translation initiation factor eIF4AII; induction of neural fold genes." Development 124, no. 14 (July 15, 1997): 2751–60. http://dx.doi.org/10.1242/dev.124.14.2751.
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Expression of the RNA-helicase translation initiation factor, eIF4AII, in animal cap explants of Xenopus specifically upregulates genes expressed early in the neural plate border such as Xsna, Xslu, Pax-3 and XANF and also the cement gland marker XCG-1. eIF4AII is expressed specifically in the prospective neurectoderm from stage 11.5 and appears to have a significant role in mediating early patterning of the neurectoderm. It is induced by all known neural inducing regimes including secreted factors such as noggin, follistatin and chordin, transcription factors such as XlPou-2 and constructs that overcome repression of neural induction (tBMP-4R, lim-m3 and Xbra delta 304). It is also upregulated when neurulization occurs in embryonic ectoderm that has been disaggregated and reaggregated. While high amounts of injected mRNA of the neural inducers noggin, tBMP-4R and Xlpou-2 downregulate Xslu and upregulate the neural plate NCAM, smaller amounts of these mRNAs activate expression of eIF4AII and Xslu and suppress expression of epidermal keratin in animal cap assays. Ectopic expression of eIF4AII mRNA also upregulates transcription of the PKC alpha and beta genes. The sensitivity of the upregulation of neurectodermal markers to GF109203X indicates that the activity of a calcium activated protein kinase C (PKC) is also required. Furthermore ectopic expression of mouse eIF4AII mRNA upregulates the endogenous eIF4AII gene by a process that requires the activity of PKC. The effects of eIF4AII appear to be direct as conditional expression of eIF4AII in animal cap explants at the equivalent of stage 11.5 induces the endogenous eIF4AII and neural fold genes within 40 minutes. Expression of eIF4AII and activation of PKC sensitizes the embryonic ectoderm to the neuralising effect of noggin. We suggest that in developing embryos the neuralizing signal emanating from the organiser at first induces eIF4AII and the prospective neural crest in an arc low on the dorsal aspect of the embryo. As the neuralizing signal increases in intensity close to the organizer region, the tissue becomes committed to a neural plate phenotype. Expression of Xash-3A may suppress further expression of neural plate border genes within the prospective neural plate thereby subdividing the neurectoderm into two distinct regions.
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Ermakova, G. V., E. M. Alexandrova, O. V. Kazanskaya, O. L. Vasiliev, M. W. Smith, and A. G. Zaraisky. "The homeobox gene, Xanf-1, can control both neural differentiation and patterning in the presumptive anterior neurectoderm of the Xenopus laevis embryo." Development 126, no. 20 (October 15, 1999): 4513–23. http://dx.doi.org/10.1242/dev.126.20.4513.
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From the onset of neurectoderm differentiation, homeobox genes of the Anf class are expressed within a region corresponding to the presumptive telencephalic and rostral diencephalic primordia. Here we investigate functions of the Xenopus member of Anf, Xanf-1, in the differentiation of the anterior neurectoderm. We demonstrate that ectopic Xanf-1 can expand the neural plate at expense of adjacent non-neural ectoderm. In tadpoles, the expanded regions of the plate developed into abnormal brain outgrowths. At the same time, Xanf-1 can inhibit terminal differentiation of primary neurones. We also show that, during gastrula/neurula stages, the exogenous Xanf-1 can downregulate four transcription regulators, XBF-1, Otx-2, Pax-6 and the endogenous Xanf-1, that are expressed in the anterior neurectoderm. However, during further development, when the exogenous Xanf-1 was presumably degraded, re-activation of XBF-1, Otx-2 and Pax-6 was observed in the abnormal outgrowths developed from blastomeres microinjected with Xanf-1 mRNA. Other effects of the ectopic Xanf-1 include cyclopic phenotype and inhibition of the cement gland, both by Otx-2-dependent and -independent mechanisms. Using fusions of Xanf-1 with the repressor domain of Drosophila engrailed or activator domain of herpes virus VP16 protein, we showed that most of the observed effects of Xanf-1 were probably elicited by its functioning as a transcription repressor. Altogether, our data indicate that the repressor function of Xanf-1 may be necessary for regulation of both neural differentiation and patterning in the presumptive anterior neurectoderm.
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Lu, Pengfei, Meredith Barad, and Peter D. Vize. "Xenopus p63 expression in early ectoderm and neurectoderm." Mechanisms of Development 102, no. 1-2 (April 2001): 275–78. http://dx.doi.org/10.1016/s0925-4773(01)00315-x.
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Rhinn, M., A. Dierich, M. Le Meur, and S. Ang. "Cell autonomous and non-cell autonomous functions of Otx2 in patterning the rostral brain." Development 126, no. 19 (October 1, 1999): 4295–304. http://dx.doi.org/10.1242/dev.126.19.4295.
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Previous studies have shown that the homeobox gene Otx2 is required first in the visceral endoderm for induction of forebrain and midbrain, and subsequently in the neurectoderm for its regional specification. Here, we demonstrate that Otx2 functions both cell autonomously and non-cell autonomously in neurectoderm cells of the forebrain and midbrain to regulate expression of region-specific homeobox and cell adhesion genes. Using chimeras containing both Otx2 mutant and wild-type cells in the brain, we observe a reduction or loss of expression of Rpx/Hesx1, Wnt1, R-cadherin and ephrin-A2 in mutant cells, whereas expression of En2 and Six3 is rescued by surrounding wild-type cells. Forebrain Otx2 mutant cells subsequently undergo apoptosis. Altogether, this study demonstrates that Otx2 is an important regulator of brain patterning and morphogenesis, through its regulation of candidate target genes such as Rpx/Hesx1, Wnt1, R-cadherin and ephrin-A2.
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Cruz, YP, A. Yousef, and L. Selwood. "Fate-map analysis of the epiblast of the dasyurid marsupial Sminthopsis macroura (Gould)." Reproduction, Fertility and Development 8, no. 4 (1996): 779. http://dx.doi.org/10.1071/rd9960779.
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Allocation of cells in the marsupial epiblast to embryonic and extra-embryonic domains has to date been studied only histologically. An unresolved issue in marsupial embryology has been the existence of a medullary plate. We re-examined the hypotheses that the medullary plate, or neurectoderm, arises before notochord formation and that the integumentary ectoderm is segregated from the ectoderm after the formation of the medullary plate. By marking epiblast cells in 65 Day-8 embryos of the dasyurid marsupial Sminthopsis macroura, with the lipophilic cell-surface marker, DiI, we demonstrated that the so-called medullary plate contains progenitors of the integumentary ectoderm of the neck, chest, limbs and flank of the embryo. Thus, cell-allocation processes in the epiblast must have segregated the entire complement of embryonic ectoderm in one event, not separate events. It is concluded that the embryonic structure called 'medullary plate' in marsupial embryos is misnamed since, in fact, it consists of both integumentary ectoderm and neurectoderm.
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Arkell, R., and R. S. Beddington. "BMP-7 influences pattern and growth of the developing hindbrain of mouse embryos." Development 124, no. 1 (January 1, 1997): 1–12. http://dx.doi.org/10.1242/dev.124.1.1.
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The expression pattern of bone morphogenetic protein-7 (BMP-7) in the hindbrain region of the headfold and early somite stage developing mouse embryo suggests a role for BMP-7 in the patterning of this part of the cranial CNS. In chick embryos it is thought that BMP-7 is one of the secreted molecules which mediates the dorsalizing influence of surface ectoderm on the neural tube, and mouse surface ectoderm has been shown to have a similar dorsalizing effect. While we confirm that BMP-7 is expressed in the surface ectoderm of mouse embryos at the appropriate time to dorsalize the neural tube, we also show that at early stages of hindbrain development BMP-7 transcripts are present in paraxial and ventral tissues, within and surrounding the hindbrain neurectoderm, and only later does expression become restricted to a dorsal domain. To determine more directly the effect that BMP-7 may have on the developing hindbrain we have grafted COS cells expressing BMP-7 into the ventrolateral mesoderm abutting the neurectoderm in order to prolong BMP-7 expression in the vicinity of ventral hindbrain. Three distinct actvities of BMP-7 are apparent. Firstly, as expected from previous work in chick, BMP-7 can promote dorsal characteristics in the neural tube. Secondly, we show that it can also attenuate the expression of sonic hedgehog (Shh) in the floorplate without affecting Shh expression in the notochord. Finally, we find that ectopic BMP-7 appears to promote growth of the neurectoderm. These findings are discussed with respect to possible timing mechanisms necessary for the coordination of hindbrain dorsoventral patterning.
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Gamse, Joshua T., and Hazel Sive. "Early anteroposterior division of the presumptive neurectoderm in Xenopus." Mechanisms of Development 104, no. 1-2 (June 2001): 21–36. http://dx.doi.org/10.1016/s0925-4773(01)00358-6.
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Gamse, Joshua, and Hazel Sive. "Vertebrate anteroposterior patterning: the Xenopus neurectoderm as a paradigm." BioEssays 22, no. 11 (October 25, 2000): 976–86. http://dx.doi.org/10.1002/1521-1878(200011)22:11<976::aid-bies4>3.0.co;2-c.
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Cambray, Noemí, and Valerie Wilson. "Axial progenitors with extensive potency are localised to the mouse chordoneural hinge." Development 129, no. 20 (October 15, 2002): 4855–66. http://dx.doi.org/10.1242/dev.129.20.4855.
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Elongation of the mouse anteroposterior axis depends on a small population of progenitors initially located in the primitive streak and later in the tail bud. Gene expression and lineage tracing have shown that there are many features common to these progenitor tissues throughout axial elongation. However, the identity and location of the progenitors is unclear. We show by lineage tracing that the descendants of 8.5 d.p.c. node and anterior primitive streak which remain in the tail bud are located in distinct territories: (1) ventral node descendants are located in the widened posterior end of the notochord; and (2) descendants of anterior streak are located in both the tail bud mesoderm, and in the posterior end of the neurectoderm. We show that cells from the posterior neurectoderm are fated to give rise to mesoderm even after posterior neuropore closure. The posterior end of the notochord, together with the ventral neurectoderm above it, is thus topologically equivalent to the chordoneural hinge region defined in Xenopus and chick. A stem cell model has been proposed for progenitors of two of the axial tissues, the myotome and spinal cord. Because it was possible that labelled cells in the tail bud represented stem cells, tail bud mesoderm and chordoneural hinge were grafted to 8.5 d.p.c. primitive streak to compare their developmental potency. This revealed that cells from the bulk of the tail bud mesoderm are disadvantaged in such heterochronic grafts from incorporating into the axis and even when they do so, they tend to contribute to short stretches of somites suggesting that tail bud mesoderm is restricted in potency. By contrast, cells from the chordoneural hinge of up to 12.5 d.p.c. embryos contribute efficiently to regions of the axis formed after grafting to 8.5 d.p.c. embryos, and also repopulate the tail bud. These cells were additionally capable of serial passage through three successive generations of embryos in culture without apparent loss of potency. This potential for self-renewal in chordoneural hinge cells strongly suggests that stem cells are located in this region.
Dissertations / Theses on the topic "Neurectoderm"
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Lourenco, da Conceicao Luz Marta. "Cellular mechanisms involved in Wnt8 distribution and function in zebrafish neurectoderm patterning." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1228815553128-55176.
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Wnt proteins have key roles in patterning of multicellular animals, acting at a distance from their sites of production. However, it is not well understood how these molecules propagate. This question has become even more puzzling by the discovery that Wnts harbour post-translational lipid-modifications, which enhance association with membranes and may therefore limit propagation by simple diffusion in an aqueous environment. The cellular mechanisms involved in Wnt propagation are largely unknown for vertebrate organisms. Here, I discuss my findings on the cellular localization of zebrafish Wnt8, as an example of a vertebrate Wnt. Wnt8 is a key signal for positioning the midbrain-hindbrain brain boundary (MHB) organizer along the anterior-posterior axis of the developing brain in vertebrates. However, it is not clear how this protein propagates from its source, the blastoderm margin, to the target cells, in the prospective neural plate. For this purpose, I have analysed a biologically active, fluorescently tagged Wnt8 in live zebrafish embryos. Wnt8 was present in live tissue in membrane associated punctate structures. In Wnt8 expressing cells these puncta localise to filopodial cellular processes, from which the protein is released to neighbouring cells. This filopodial release requires posttranslational palmitoylation. Although palmitoylation-defective Wnt8 retains auto- and juxtacrine signaling activity, it fails to signal over a long-range. Additionally, this Wnt8 palmitoylation is necessary for regulation of its neural plate target genes. These results suggest that vertebrate Wnt proteins use cell-to-cell contact through filopodia as a shortrange propagation mechanism while released palmitoylated Wnt is required for longrange signaling activity. Furthermore, I show that a Wnt8 receptor, Frizzled9 can negatively influence Wnt8 propagation and signaling range. Finally, I was able to determine the presence of an endogenous Wnt8 gradient in the neurectoderm. I discuss these findings in the context of Wnt8 signaling function in mediating anterior-posterior patterning during early brain development.
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Kolm, Peggy J. (Peggy Jeannette). "Patterning of the posterior neurectoderm by labial-like Hox genes and retinoids." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43468.
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Lourenco, da Conceicao Luz Marta. "Cellular mechanisms involved in Wnt8 distribution and function in zebrafish neurectoderm patterning." Doctoral thesis, Technische Universität Dresden, 2007. https://tud.qucosa.de/id/qucosa%3A23716.
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Wnt proteins have key roles in patterning of multicellular animals, acting at a distance from their sites of production. However, it is not well understood how these molecules propagate. This question has become even more puzzling by the discovery that Wnts harbour post-translational lipid-modifications, which enhance association with membranes and may therefore limit propagation by simple diffusion in an aqueous environment. The cellular mechanisms involved in Wnt propagation are largely unknown for vertebrate organisms. Here, I discuss my findings on the cellular localization of zebrafish Wnt8, as an example of a vertebrate Wnt. Wnt8 is a key signal for positioning the midbrain-hindbrain brain boundary (MHB) organizer along the anterior-posterior axis of the developing brain in vertebrates. However, it is not clear how this protein propagates from its source, the blastoderm margin, to the target cells, in the prospective neural plate. For this purpose, I have analysed a biologically active, fluorescently tagged Wnt8 in live zebrafish embryos. Wnt8 was present in live tissue in membrane associated punctate structures. In Wnt8 expressing cells these puncta localise to filopodial cellular processes, from which the protein is released to neighbouring cells. This filopodial release requires posttranslational palmitoylation. Although palmitoylation-defective Wnt8 retains auto- and juxtacrine signaling activity, it fails to signal over a long-range. Additionally, this Wnt8 palmitoylation is necessary for regulation of its neural plate target genes. These results suggest that vertebrate Wnt proteins use cell-to-cell contact through filopodia as a shortrange propagation mechanism while released palmitoylated Wnt is required for longrange signaling activity. Furthermore, I show that a Wnt8 receptor, Frizzled9 can negatively influence Wnt8 propagation and signaling range. Finally, I was able to determine the presence of an endogenous Wnt8 gradient in the neurectoderm. I discuss these findings in the context of Wnt8 signaling function in mediating anterior-posterior patterning during early brain development.
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Lourenço, da Conceição Luz Marta. "Cellular mechanisms involved in Wnt8 distribution and function in zebrafish neurectoderm patterning." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1228815553128-55176.
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Glover, Hannah Jacquilyn. "L-proline-induced transition of mouse ES cells to a spatially distinct primitive ectoderm-like cell population primed for neural differentiation." Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/20576.
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Naïve mouse embryonic stem cells (mESCs) derived from the preimplantation mouse blastocyst self-renew in the presence of LIF and BMP4. These cells are pluripotent, meaning they have the ability to differentiate into the ~200 cell types of the developing embryo and adult. Naïve mESCs are one discrete state along a pluripotency continuum – delimited by ground-state mESCs as the earliest cell population, followed by naïve mESCs, and with EpiSCs as the most ‘primed’ population. The amino acid L-proline has novel growth factor-like properties during development - from improving blastocyst development to driving neurogenesis. Addition of 400 μM L-proline to naïve mESCs produces a pluripotent cell population between naïve mESCs and EpiSCs. These cells, named early primitive ectoderm-like (EPL) cells, recapitulate in vivo development of the pre-implantation inner cell mass to the postimplantation primitive ectoderm. EPL cells maintain expression of the naïve marker Rex1 and upregulate expression of the primitive ectoderm genes Dnmt3b and Fgf5. This thesis identifies mechanisms underpinning L-proline-mediated differentiation to EPL cells, including a complex self-regulating signalling network involving the MAPK, Fgfr, PI3K and mTOR pathways. Statistical models were used to understand the contributions of individual signalling pathways to changes in colony morphology, cell number, gene expression, proliferation and apoptosis. Other mechanisms underpinning the naïve mESCs-to-EPL cell transition were explored, including DNA methylation, histone acetylation, proline synthesis and metabolism. In addition to expressing primed pluripotency genes, EPL cells upregulate genes associated with neurogenesis, whereas EpiSCs express genes associated with cardiovascular development. When mapped to the 7.0 dpc embryo, EPL cells and EpiSCs represent spatially distinct cell populations. This suggests that after cells transition from naïve mESCs, they diverge and are fated to become either ectoderm (from EPL cells), or mesendoderm (from EpiSCs). This thesis also explored whether L-proline plays an underappreciated role in existing neural differentiation protocols. mESCs cultured in custom N2B27 medium without L-proline had reduced selective cell death resulting in a larger yield of Sox1+ neurectoderm.
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Häussler, Maximilian. "Prediction of tissue-specific cis-regulatory sequences : application to the ascidian Ciona intestinalis and the anterior neurectoderm." Paris 11, 2009. http://www.theses.fr/2009PA112078.
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Au cours de mon travail de thèse, j'ai établi une procédure pour ordonner des motifs courts selon leur distribution dans le génome de C. Intestinalis autour d'un ensemble de gènes : plus une combinaison de motifs est regroupée autour des gènes exprimés spécifiquement dans un tissu, plus le score est élevé. Dans cette approche, j'ai intégré les résultats de la dissection d'un enhancer exprimé dans le neurectoderme antérieur qui indiquait une structure dupliquée. Ma procédure montre que les sites GATTA dupliqués sont une caractéristique générale des éléments cis-régulateurs du neurectoderme antérieur. Une recherche dans le génome entier pour ces séquences suivi par un test in-vivo montre une expression dans ce territoire pour la moitié des éléments. Par la suite, j'ai essayé d'améliorer l'annotation des séquences cis-régulatrices déjà publiées, par une extraction automatique à partir de la littérature. Grâce à l'augmentation du nombre de publications en accès libre et l'amélioration des procédures expérimentales de plus en plus de ce type de données est disponible. Finalement, j'ai montré que malgré l'absence d'alignements non-codants entre les génomes des vertébrés et C. Intestinalis, on peut cependant trouver quelques loci avec une conservation extrême de l'arrangement des gènes. Pour ces cas, la recherche des éléments cis-régulateurs peut être limitée aux introns du gène voisin, ce qui était confirmé dans la littérature pour certains. Ces trois approches montrent l'utilité de la bioinformatique pour une meilleure caractérisation des séquences cis-régulatrices et ouvrent la voie aux validations expérimentales supplémentairesIn this thesis, a procedure is presented to rank combinations of short sequence motifs by their distribution around a set of genes. The better a combination matches around genes expressed in a certain tissue, the higher is its score. I applied this to an already characterized enhancer of C. Intestinalis expressed in the anterior neurectoderm which had been found by systematic mutations to be composed of a duplicated structure. The results of my procedure indicated that duplicated GA TTA-sites are an essential feature of cis-regulatory elements active in the anterior neurectoderm. Searching the genome for matches to this signature resulted in putative enhancers that drive a reporter gene in 50% of the cases in the anterior neurectoderm. In addition, I tried to improve the curation of already published cis-regulatory elements by extracting them automatically from the full text of the biological research articles. Thanks to the thriving open access publishing model and the improvement in experimental assays, more and more of this data is becoming available. Finally, I showed that in the absence of non-coding sequence alignments between the genomes of vertebrate and C. Intestinalis, one can nevertheless find a handful of loci with a very unusually conserved gene order. In these cases, the cis-regulatory search space is reduced to a set of introns, some of which were recently shown to harbor enhancers. Many of these loci have not been analyzed yet. Together, these computational approaches should lead to a better characterization of cis-regulatory sequences and pave the way for further experimental validations
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Gammill, Laura Susan 1969. "Patterning the Xenopus neurectoderm : the role of otx2 in the determination of cement gland and anterior neural fates." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/49651.
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Demilly, Adrien. "Neurogenèse et architecture du neurectoderme chez l'annélide Platynereis dumerilii." Paris 7, 2012. http://www.theses.fr/2012PA077178.
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De nombreuses études, menées sur des organismes modèles tels que la drosophile ou les vertébrés, ont dévoilé en partie les mécanismes qui contrôlent le développement du système nerveux des animaux bilatériens. En revanche, la mise en place de ces mécanismes au cours de l'évolution, les aspects qui en ont été conservés et ceux qui ont divergé, restent des questions largement irrésolues. Cette thèse aborde plusieurs aspects de la neurogenèse chez un organisme modèle original, Pannélide Platynereis dumerilii. Une description détaillée de l'architecture du neurectoderme larvaire y est présentée, et le rôle des voies de signalisations moléculaires Wnt//3-catenin et Planar Cell Polarity, impliquées dans plusieurs aspects de la neurogenèse chez les vertébrés et la drosophile, y est étudié, chez Platynereis, par le biais d'inhibiteurs pharmacologiques. Les résultats suggèrent que la voie Wnt//3-catenin stimule la différenciation des progéniteurs neuraux, tandis que la voie PCP semble participer aux événements précoces de fusion du neurectoderme. Enfin, une étude détaillée du profil d'expression des gènes coe est présentée à la fois dans le neurectoderme de Platynereis et dans la chaîne nerveuse ventrale de drosophile, et suggère une implication ancestrale de la famille dans la différenciation des neurones. L'ensemble des résultats est discuté en détails et remis dans un contexte évolutif par la comparaison systématique avec les données déjà connues chez d'autres organismes modèles. Plusieurs hypothèses et scénarii évolutifs sont ainsi proposés pour tenter de retracer l'histoire évolutive de différents caractères liés à la neurogenèse chez les bilatériensMany studies, performed on classical model organisms such as vertebrates and Drosophila, shed light on some important mechanisms that govern the development of the central nervous system in bilaterian animals. However, the emergence of these mechanisms during the course of evolution, the aspects that have been conserved and those that have diverged, are still mostly unknown. This thesis focuses on several aspects of neurogenesis in an original model organism, the annelid Platynereis dumerilii. A detailed description of the neurectoderm and its architecture are presented, and the roles of two major signalling pathways, Wnt//3catenin and Planar Cell Polarity, involved in many aspects of neurogenesis in flies and vertebrates, are assessed in Platynereis using pharmacological inhibitors. The results suggest that the Wnt//3catenin pathway promotes the differentiation of neural progenitor cells, whereas the PCP pathway seems to be involved in the earl events of neurectoderm fusion. Finally, a detailed study of the expression profile ofcoe genes is presented, both in Platynereis and in the ventral nerve chord of Drosophila, and suggest that this gene family has an ancestral fonction in promoting neuron differentiation. All results are discussed in a wide evolutionary context by a systematic comparison with data obtained on other model organisms. Several hypotheses and evolutionary scenario are thus proposed to try to trace back the evolutionary history of several aspects of neurogenesis in bilaterians
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Häussler, Maximilian. "Prédiction des séquences cis-regulatrices tissu-spécifiques: application à l'ascidie Ciona intestinalis et au neurectoderme antérieur." Phd thesis, Université Paris Sud - Paris XI, 2009. http://tel.archives-ouvertes.fr/tel-00413501.
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The detection and annotation of cis-regulatory sequences is a difficult problem. There is currently no generally applicable experimental procedure or computational algorithm to identify the non-coding regions of the genome that serve to activate gene expression in a given cell type. The only indicator of cis-regulatory function is the conservation of a sequence in other genomes. Regions can then be tested one-by-one in transgenic assays but this is time-consuming in vertebrates. Only a limited number of these already validated cis-regulatory sequences have been curated in biological databases. One of the main advantages of the model organism Ciona intestinalis is that cis-regulatory tests can be conducted very easily and the result is observable after one day while the animal follows the chordate body plan. However, a sequence found to be active in this organism can currently not be mapped to genomes of other animals.
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Lourenço, da Conceição Luz Marta [Verfasser]. "Cellular mechanisms involved in Wnt8 distribution and function in zebrafish neurectoderm patterning / von Marta Lourenço da Conceição Luz." 2008. http://d-nb.info/992030269/34.
Full textBook chapters on the topic "Neurectoderm"
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Shparberg, Rachel A., Hannah J. Glover, and Michael B. Morris. "Embryoid Body Differentiation of Mouse Embryonic Stem Cells into Neurectoderm and Neural Progenitors." In Methods in Molecular Biology, 273–85. New York, NY: Springer New York, 2019. http://dx.doi.org/10.1007/978-1-4939-9631-5_21.
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Greenspan, Ralph J. "Initial Determination of the Neurectoderm in Drosophila." In Determinants of Neuronal Identity, 155–88. Elsevier, 1992. http://dx.doi.org/10.1016/b978-0-12-638280-8.50010-2.
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Prabakaran, M., and B. Natrajan. "Primitive Neurectodermal Tumor (PNET) Left." In Diagnostic Atlas of Pediatric Imaging: Chest and Mediastinum, 80. Jaypee Brothers Medical Publishers (P) Ltd., 2010. http://dx.doi.org/10.5005/jp/books/11045_71.
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