Glycoconjugates in normal and abnormal secondary neurulation
Autor: | Hsieh T, Griffith Cm, E. J. Sanders, Smith C |
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Rok vydání: | 1995 |
Předmět: |
Tail
Embryology animal structures Survival Health Toxicology and Mutagenesis Mesenchyme Notochord Tretinoin Chick Embryo Nervous System Malformations Toxicology Nervous System Lectins medicine Animals Neural Tube Defects Microscopy Immunoelectron biology Neuroectoderm Cell Membrane Embryogenesis Neural tube Abnormalities Drug-Induced Membrane Proteins Lectin Anatomy Immunohistochemistry Extracellular Matrix Cell biology body regions Neuroepithelial cell Neurulation medicine.anatomical_structure embryonic structures biology.protein Electrophoresis Polyacrylamide Gel Glycoconjugates DNA Damage Developmental Biology |
Zdroj: | Teratology. 52:286-297 |
ISSN: | 1096-9926 0040-3709 |
Popis: | In chick embrayos, the anterior greater portion of the neural tube develops by the folding, apposition, and fusion of the neuroectoderm. The smaller caudal portion that forms the secondary neural tube (lumbosacral and coccygeal regions) is derived from the tail bud, an aggregate of mesenchymal cells located at the caudal limit of the body. Tail bud mesenchyme, arranged in a solid cord, undergoes mesenchymal- epithelial transformation to form the secondary neural tube. Previous evidence suggests that this transformation is accompanied by modulation of cell surface glycoconjugates in the differentiating tissues. In this study, we show by lectin histochemistry and lectin blotting of proteins isolated by SDS-PAGE, that Datura stramonium agglutinin (DSA) binds preferentially to differentiating tail bud cells. This lectin is specific for β1-4-linked N-acetylglucosamine oligomers, such as the oligosaccharides of the poly-N-acetyllactosamine series that have been previously implicated in cell differentiation. Ultrastructural lectin cytochemistry indicates that at least some of the proteins binding DSA are localized extracellularly. The use of DSA as a teratogen resulted in embryos showing a variety of neural tube and notochord defects. We have also examined the binding of DSA to embryos that were treated with teratogenic doses of retinoic acid by sub-blastodermal injection, and find that the DSA- binding patterns are perturbed. Analysis of DSA- treated embryos using the TUNEL technique indicated that cell death was not a factor in DSA teratogenesis. This strongly suggests that the glycoconjugates of the cell surface have a role in the normal differentiation of tail bud mesenchyme into the neuroepithelium of the secondary neural tube. Perturbations of glycoconjugate activity results in defects of the secondary neural tube and associated tail bud derivatives. © 1995 Wiley-Liss, Inc. |
Databáze: | OpenAIRE |
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