Search results for "Embryonic Stem Cell"
showing 10 items of 223 documents
Fate-mapping in the procephalic region of the embryonic Drosopbila head
1994
Using intracellular horseradish peroxidase injection we traced the developmental fate of early gastrula cells of the procephalic region in the stage 16/17 embryo. Morphogenetic movements in the developing brain are described in three dimensions. The results are related to head segmentation, and an early gastrula fate map of pregnathal head segments is proposed.
Notch and Numb are required for normal migration of peripheral glia in Drosophila
2006
Abstract A prominent feature of glial cells is their ability to migrate along axons to finally wrap and insulate them. In the embryonic Drosophila PNS, most glial cells are born in the CNS and have to migrate to reach their final destinations. To understand how migration of the peripheral glia is regulated, we have conducted a genetic screen looking for mutants that disrupt the normal glial pattern. Here we present an analysis of two of these mutants: Notch and numb. Complete loss of Notch function leads to an increase in the number of glial cells. Embryos hemizygous for the weak NotchB-8X allele display an irregular migration phenotype and mutant glial cells show an increased formation of …
Sonic hedgehog promotes the migration and proliferation of optic nerve oligodendrocyte precursors.
2007
Optic nerve (ON) oligodendrocyte precursors (OPCs) are generated under the influence of the Sonic hedgehog (Shh) in the preoptic area from where they migrate to colonise the entire nerve. The molecular events that control this migration are still poorly understood. Recent studies suggested that Shh is often used by the same cell population to control different processes, including cell proliferation and migration, raising the possibility that Shh could contribute to these aspects of OPC development. In support of this idea, we show here that Shh induces the proliferation of OPCs derived from embryonic mouse ON explants and acts as a chemoattractant for their migration. In ovo injections of …
Molecular mechanisms in developmental biology.
1996
Some general molecular mechanisms underlying development are described. Namely: those involved in the differentiation of the R7 receptor in Drosophila embryonic retina; those involved in the determination of embryonic axes and in polar cell differentiation, in Drosophila; those involved in the determination of the AB and P cell lineage and in vulva differentiation in Caenorhabditis embryos.
Die endokrinen dr�sen im embryo von Oncopeltus fasciatus Dallas (Insecta, Heteroptera)
1972
The differentiation of the endocrine glands in the embryo of Oncopeltus fasciatus is described. The function of these glands can be correlated with the embryonic moults. The nuclei of some tissues already become polyploid in the embryo. It is discussed whether the endomitotic growth is dependent upon the function of the endocrine glands.
Labeling of Single Cells in the Central Nervous System of <em>Drosophila melanogaster</em>
2013
In this article we describe how to individually label neurons in the embryonic CNS of Drosophila melanogaster by juxtacellular injection of the lipophilic fluorescent membrane marker DiI. This method allows the visualization of neuronal cell morphology in great detail. It is possible to label any cell in the CNS: cell bodies of target neurons are visualized under DIC optics or by expression of a fluorescent genetic marker such as GFP. After labeling, the DiI can be transformed into a permanent brown stain by photoconversion to allow visualization of cell morphology with transmitted light and DIC optics. Alternatively, the DiI-labeled cells can be observed directly with confocal microscopy, …
Hype and Hopes of Stem Cell Research in Neurodegenerative Diseases
2017
Hope from the regeneration promoting effects of stem cells have provided new insights for understanding diseases that were previously thought to have a limited prognostic improvement upon medical intervention. This is especially indicated in neurodegenerative diseases, which until the discovery and research in stem cells were thought to have minimal regenerative capabilities. This review covers various treatment modalities involving different types of stem cells, such as human embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells and neural stem cells, which have been tested for various neurodegenerative disorders such as Multiple Sclerosis, Alzheimer’s disease, Parki…
Ionic currents ofdrosophila embryonic neurons derived from selectively cultured CNS midline precursors
2000
In order to investigate the electrogenesis of defined cell populations, we applied an in vitro system that allows the selective culturing of individual Drosophila CNS precursors under different conditions. CNS midline (ML) precursors prepared from gastrula stage embryos gave rise to progeny cells with neuronal and glial morphology that expressed specific markers. Using whole-cell patch-clamp recordings, a detailed description of ionic currents present in this defined cell population is provided. Most ionic currents of cultured ML neurons were similar to other cultured Drosophila neurons, even though their embryonic origin is different. They displayed at least two voltage-gated potassium cur…
Cell lineage and cell fate specification in the embryonic CNS of Drosophila.
1997
The Drosophila CNS derives from a population of neural stem cells, called neuroblasts (NBs), which delaminate individually from the neurogenic region of the ectoderm. In the embryonic ventral nerve cord each NB can be uniquely identified and gives rise to a specific lineage consisting of neurons and/or glial cells. This 'NB identity' is dependent on the position of the progenitor cells in the neuroectoderm before delamination. The positional information is provided by the products of segment polarity and dorsoventral (D/V) patterning genes. Subsequently, 'cell fate genes' like huckebein (hkb) and eagle (eg) contribute to the generation of specific NB lineages. These genes act downstream of …
Decorin Expression and Oncosuppression in Human Embryonic Carcinomas
2019
Human embryonic stem cells in culture can transform into malignant, cancer-like cells exhibiting lesser differentiation. After transplantation, these transformed cells can form highly malignant germ cell tumors. In humans, germ cell tumors often appear at gonadal sites, like in the testis. In this study, we examined the expression of small leucine rich proteoglycans in normal and karyotypically abnormal human embryonic stem cells using a publicly available transcriptome data. We also examined the expression of the small leucine rich proteoglycans in healthy human testis and in different human testicular non-seminoma germ cell tumors using IST Online database. Furthermore, we localized the e…