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Zhang P, Li T, Liu C, Sindi M, Cheng X, Qi S, Liu X, Yan Y, Bao Y, Brand-Saberi B, Yang W, Wang G, Yang X. Nano-sulforaphane attenuates PhIP-induced early abnormal embryonic neuro-development. Ann Anat 2020; 233:151617. [PMID: 33098981 DOI: 10.1016/j.aanat.2020.151617] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 09/16/2020] [Accepted: 09/25/2020] [Indexed: 12/19/2022]
Abstract
BACKGROUND 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyrimidine (PhIP), one of the most abundant heterocyclic aromatic amines (HAA) formed by cooking meat at high temperatures, may modify humans and rodents through the metabolic process prior to affecting nervous system development. In humans and rodents may be modified by metabolic processes and then affecting nervous system development. METHODS In this paper, PhIP was used to prepare a chicken embryo model with abnormal embryonic nervous system defects. Sulforaphane (SFN) is a derivative of a glucosinolate, which is abundant in cruciferous vegetables, and can pass through the placental barrier. Moreover, SFN has antioxidant and anti-apoptotic functions and is considered as a bioactive antioxidant with significant neuroprotective effects. Nano-sulforaphane (Nano-SFN, sulforaphane nanoparticles) was prepared by self-assembly using biocompatible, biodegradable methoxy polyethylene glycol 5000-b-polyglutamic acid 10,000 (mPEG5K-PGA10K) as the substrate, to explore the new application of Nano-SFN and its modified compounds as leading compounds in protecting against the abnormal development of the embryonic nervous system. RESULTS The results show that Nano-SFN could protect against PhIP-induced central nervous system (CNS, derived from neural tube) and peripheral nervous system (PNS, derived from neural crest cells, NCCs) defects and neural tube defects (NTDs), and increase the embryo survival rate. CONCLUSIONS This study indicates that Nano-SFN can effectively alleviate the developmental defects of embryonic nervous system induced by PhIP in the microenvironment and has a protective effect on embryonic development. It not only helps with expanding the application of SFN and improving its medicinal value, but also provides a possibility of SFN being developed as a novel drug for neuroprotection.
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Affiliation(s)
- Ping Zhang
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632, China; Key Laboratory for Regenerative Medicine of the Ministry of Education, Jinan University, Guangzhou 510632, China
| | - Tingting Li
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632, China; Key Laboratory for Regenerative Medicine of the Ministry of Education, Jinan University, Guangzhou 510632, China
| | - Chang Liu
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632, China; Key Laboratory for Regenerative Medicine of the Ministry of Education, Jinan University, Guangzhou 510632, China
| | - Mustafa Sindi
- Department of Anatomy and Molecular Embryology, Institute of Anatomy, Ruhr University Bochum, Universitätsstrasse 150, 44801 Bochum, Germany
| | - Xin Cheng
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632, China
| | - Shuangyu Qi
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632, China
| | - Xinyue Liu
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632, China
| | - Yu Yan
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632, China; Key Laboratory for Regenerative Medicine of the Ministry of Education, Jinan University, Guangzhou 510632, China
| | - Yongping Bao
- Norwich Medical School, University of East Anglia, Norwich, Norfolk NR4 7UQ, UK
| | - Beate Brand-Saberi
- Department of Anatomy and Molecular Embryology, Institute of Anatomy, Ruhr University Bochum, Universitätsstrasse 150, 44801 Bochum, Germany
| | - Weidong Yang
- College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Guang Wang
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632, China; Key Laboratory for Regenerative Medicine of the Ministry of Education, Jinan University, Guangzhou 510632, China.
| | - Xuesong Yang
- International Joint Laboratory for Embryonic Development & Prenatal Medicine, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632, China; Key Laboratory for Regenerative Medicine of the Ministry of Education, Jinan University, Guangzhou 510632, China.
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Washausen S, Scheffel T, Brunnett G, Knabe W. Possibilities and limitations of three-dimensional reconstruction and simulation techniques to identify patterns, rhythms and functions of apoptosis in the early developing neural tube. HISTORY AND PHILOSOPHY OF THE LIFE SCIENCES 2018; 40:55. [PMID: 30159859 DOI: 10.1007/s40656-018-0222-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 08/19/2018] [Indexed: 06/08/2023]
Abstract
The now classical idea that programmed cell death (apoptosis) contributes to a plethora of developmental processes still has lost nothing of its impact. It is, therefore, important to establish effective three-dimensional (3D) reconstruction as well as simulation techniques to decipher the exact patterns and functions of such apoptotic events. The present study focuses on the question whether and how apoptosis promotes neurulation-associated processes in the spinal cord of Tupaia belangeri (Tupaiidae, Scandentia, Mammalia). Our 3D reconstructions demonstrate that at least two craniocaudal waves of apoptosis consecutively pass through the dorsal spinal cord. The first wave appears to be involved in neural fold fusion and/or in selection processes among premigratory neural crest cells. The second one seems to assist in establishing the dorsal signaling center known as the roof plate. In the hindbrain, in contrast, apoptosis among premigratory neural crest cells progresses craniocaudally but discontinuously, in a segment-specific manner. Unlike apoptosis in the spinal cord, these segment-specific apoptotic events, however, precede later ones that seemingly support neural fold fusion and/or postfusion remodeling. Arguing with Whitehead that biological patterns and rhythms differ in that biological rhythms depend "upon the differences involved in each exhibition of the pattern" (Whitehead in An enquiry concerning the principles of natural knowledge. Cambridge University Press, London, 1919, p. 198) we show that 3D reconstruction and simulation techniques can contribute to distinguish between (static) patterns and (dynamic) rhythms of apoptosis. By deciphering novel patterns and rhythms of developmental apoptosis, our reconstructions help to reconcile seemingly inconsistent earlier findings in chick and mouse embryos, and to create rules for computer simulations.
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Affiliation(s)
- Stefan Washausen
- Department Prosektur Anatomie, Westfälische Wilhelms-University, Vesaliusweg 2-4, 48149, Münster, Germany
| | - Thomas Scheffel
- Department of Psychiatry, Psychotherapy and Psychosomatics, Brandenburg Medical School, Campus Neuruppin, 16816, Neuruppin, Germany
| | - Guido Brunnett
- Department of Informatics, Technical University, 09107, Chemnitz, Germany
| | - Wolfgang Knabe
- Department Prosektur Anatomie, Westfälische Wilhelms-University, Vesaliusweg 2-4, 48149, Münster, Germany.
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Baskin L, Shen J, Sinclair A, Cao M, Liu X, Liu G, Isaacson D, Overland M, Li Y, Cunha GR. Development of the human penis and clitoris. Differentiation 2018; 103:74-85. [PMID: 30249413 DOI: 10.1016/j.diff.2018.08.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 08/21/2018] [Accepted: 08/21/2018] [Indexed: 12/17/2022]
Abstract
The human penis and clitoris develop from the ambisexual genital tubercle. To compare and contrast the development of human penis and clitoris, we used macroscopic photography, optical projection tomography, light sheet microscopy, scanning electron microscopy, histology and immunohistochemistry. The human genital tubercle differentiates into a penis under the influence of androgens forming a tubular urethra that develops by canalization of the urethral plate to form a wide diamond-shaped urethral groove (opening zipper) whose edges (urethral folds) fuse in the midline (closing zipper). In contrast, in females, without the influence of androgens, the vestibular plate (homologue of the urethral plate) undergoes canalization to form a wide vestibular groove whose edges (vestibular folds) remain unfused, ultimately forming the labia minora defining the vaginal vestibule. The neurovascular anatomy is similar in both the developing human penis and clitoris and is the key to successful surgical reconstructions.
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Mohd-Zin SW, Marwan AI, Abou Chaar MK, Ahmad-Annuar A, Abdul-Aziz NM. Spina Bifida: Pathogenesis, Mechanisms, and Genes in Mice and Humans. SCIENTIFICA 2017; 2017:5364827. [PMID: 28286691 PMCID: PMC5327787 DOI: 10.1155/2017/5364827] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 11/14/2016] [Accepted: 12/01/2016] [Indexed: 05/26/2023]
Abstract
Spina bifida is among the phenotypes of the larger condition known as neural tube defects (NTDs). It is the most common central nervous system malformation compatible with life and the second leading cause of birth defects after congenital heart defects. In this review paper, we define spina bifida and discuss the phenotypes seen in humans as described by both surgeons and embryologists in order to compare and ultimately contrast it to the leading animal model, the mouse. Our understanding of spina bifida is currently limited to the observations we make in mouse models, which reflect complete or targeted knockouts of genes, which perturb the whole gene(s) without taking into account the issue of haploinsufficiency, which is most prominent in the human spina bifida condition. We thus conclude that the need to study spina bifida in all its forms, both aperta and occulta, is more indicative of the spina bifida in surviving humans and that the measure of deterioration arising from caudal neural tube defects, more commonly known as spina bifida, must be determined by the level of the lesion both in mouse and in man.
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Affiliation(s)
- Siti W. Mohd-Zin
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Ahmed I. Marwan
- Laboratory for Fetal and Regenerative Biology, Colorado Fetal Care Center, Division of Pediatric Surgery, Children's Hospital Colorado, University of Colorado, Anschutz Medical Campus, 12700 E 17th Ave, Aurora, CO 80045, USA
| | | | - Azlina Ahmad-Annuar
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Noraishah M. Abdul-Aziz
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Ray HJ, Niswander LA. Dynamic behaviors of the non-neural ectoderm during mammalian cranial neural tube closure. Dev Biol 2016; 416:279-85. [PMID: 27343896 DOI: 10.1016/j.ydbio.2016.06.030] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 05/26/2016] [Accepted: 06/19/2016] [Indexed: 11/27/2022]
Abstract
The embryonic brain and spinal cord initially form through the process of neural tube closure (NTC). NTC is thought to be highly similar between rodents and humans, and studies of mouse genetic mutants have greatly increased our understanding of the molecular basis of NTC with relevance for human neural tube defects. In addition, studies using amphibian and chick embryos have shed light into the cellular and tissue dynamics underlying NTC. However, the dynamics of mammalian NTC has been difficult to study due to in utero development until recently when advances in mouse embryo ex vivo culture techniques along with confocal microscopy have allowed for imaging of mouse NTC in real time. Here, we have performed live imaging of mouse embryos with a particular focus on the non-neural ectoderm (NNE). Previous studies in multiple model systems have found that the NNE is important for proper NTC, but little is known about the behavior of these cells during mammalian NTC. Here we utilized a NNE-specific genetic labeling system to assess NNE dynamics during murine NTC and identified different NNE cell behaviors as the cranial region undergoes NTC. These results bring valuable new insight into regional differences in cellular behavior during NTC that may be driven by different molecular regulators and which may underlie the various positional disruptions of NTC observed in humans with neural tube defects.
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Affiliation(s)
- Heather J Ray
- Department of Pediatrics, Cell Biology Stem Cells and Development Graduate Program, University of Colorado Anschutz Medical Campus and Children's Hospital Colorado, Aurora, CO 80045, USA
| | - Lee A Niswander
- Department of Pediatrics, Cell Biology Stem Cells and Development Graduate Program, University of Colorado Anschutz Medical Campus and Children's Hospital Colorado, Aurora, CO 80045, USA.
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Trophic and proliferative perturbations of in vivo/in vitro cephalic neural crest cells after ethanol exposure are prevented by Neurotrophin 3. Neurotoxicol Teratol 2011; 33:422-30. [DOI: 10.1016/j.ntt.2011.03.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Revised: 12/23/2010] [Accepted: 03/15/2011] [Indexed: 01/27/2023]
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Pyrgaki C, Trainor P, Hadjantonakis AK, Niswander L. Dynamic imaging of mammalian neural tube closure. Dev Biol 2010; 344:941-7. [PMID: 20558153 DOI: 10.1016/j.ydbio.2010.06.010] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Revised: 06/07/2010] [Accepted: 06/07/2010] [Indexed: 10/19/2022]
Abstract
Neurulation, the process of neural tube formation, is a complex morphogenetic event. In the mammalian embryo, an understanding of the dynamic nature of neurulation has been hampered due to its in utero development. Here we use laser point scanning confocal microscopy of a membrane expressed fluorescent protein to visualize the dynamic cell behaviors comprising neural tube closure in the cultured mouse embryo. In particular, we have focused on the final step wherein the neural folds approach one another and seal to form the closed neural tube. Our unexpected findings reveal a mechanism of closure in the midbrain different from the zipper-like process thought to occur more generally. Individual non-neural ectoderm cells on opposing sides of the neural folds undergo a dramatic change in shape to protrude from the epithelial layer and then form intermediate closure points to "button-up" the folds. Cells from the juxtaposed neural folds extend long and short flexible extensions and form bridges across the physical gap of the closing folds. Thus, the combination of live embryo culture with dynamic imaging provides intriguing insight into the cell biological processes that mold embryonic tissues in mammals.
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Affiliation(s)
- Christina Pyrgaki
- HHMI, Department of Pediatrics, Molecular Biology Graduate Program, University of Colorado Denver, Aurora, CO 80045, USA
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Abstract
Birth defects resulting from diabetic pregnancy are associated with apoptosis of a critical mass of progenitor cells early during the formation of the affected organ(s). Insufficient expression of genes that regulate viability of the progenitor cells is responsible for the apoptosis. In particular, maternal diabetes inhibits expression of a gene, Pax3, that encodes a transcription factor which is expressed in neural crest and neuroepithelial cells. As a result of insufficient Pax3, cardiac neural crest and neuroepithelial cells undergo apoptosis by a process dependent on the p53 tumor suppressor protein. This, then provides a cellular explanation for the cardiac outflow tract and neural tube and defects induced by diabetic pregnancy.
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Affiliation(s)
- James H. Chappell
- Section on Developmental and Stem Cell Biology, Joslin Diabetes Center, One Joslin Place, Boston, MA 02215, USA
| | - Xiao Dan Wang
- Section on Developmental and Stem Cell Biology, Joslin Diabetes Center, One Joslin Place, Boston, MA 02215, USA
| | - Mary R. Loeken
- Section on Developmental and Stem Cell Biology, Joslin Diabetes Center, One Joslin Place, Boston, MA 02215, USA
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Rashid D, Newell K, Shama L, Bradley R. A requirement for NF-protocadherin and TAF1/Set in cell adhesion and neural tube formation. Dev Biol 2006; 291:170-81. [PMID: 16426602 DOI: 10.1016/j.ydbio.2005.12.027] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2005] [Revised: 12/01/2005] [Accepted: 12/12/2005] [Indexed: 01/22/2023]
Abstract
Neurulation in vertebrates is an intricate process requiring extensive alterations in cell contacts and cellular morphologies as the cells in the neural ectoderm shape and form the neural folds and neural tube. Despite these complex interactions, little is known concerning the molecules that mediate cell adhesion within the embryonic neural plate and neural folds. Here, we demonstrate the requirement for NF-protocadherin (NFPC) and its cytosolic partner TAF1/Set for proper neurulation in Xenopus. Both NFPC and TAF1 function in cell-cell adhesion in the neural ectoderm, and disruptions in either NFPC or TAF1 result in a failure of the neural tube to close. This neural tube defect can be attributed to a lack of proper organization of the cells in the dorsal neural folds, manifested by a loss in the columnar epithelial morphology and apical localization of F-actin. However, the epidermal ectoderm is still able to migrate and cover the open neural tube, indicating that the fusions of the neural tube and epidermis are separate events. These studies demonstrate that NFPC and TAF1 function to maintain proper cell-cell interactions within the neural folds and suggest that NFPC and TAF1 participate in novel adhesive mechanisms that contribute to the final events of vertebrate neurulation.
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Affiliation(s)
- Dana Rashid
- Department of Cell Biology and Neuroscience, Montana State University, Bozeman, MT 59717, USA
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Abstract
Cranial neurulation is the embryonic process responsible for formation of the brain primordium. In the mouse embryo, cranial neurulation is a piecemeal process with several initiation sites and two neuropores. Variation in the pattern of cranial neurulation occurs in different mouse strains, and a simpler version of this morphogenetic scheme has been described in human embryos. Exencephaly is more common in females than in males, an unexplained phenomenon seen in both mice and humans. As the cranial neural tube closes, a critical morphogenetic event is the formation of dorsolateral bending points near the neural fold tips, which enables subsequent midline fusion of the neural folds. Many mutant and gene-targeted mouse strains develop cranial neural tube defects, and analysis of the underlying molecular defects identifies several requirements for normal dorsolateral bending. These include a functional actin cytoskeleton, emigration of the cranial neural crest, spatio-temporally regulated apoptosis, and a balance between cell proliferation and the onset of neuronal differentiation. A small number of mouse mutants exhibit craniorachischisis, a combined brain and spine neurulation defect. Recent studies show that disturbance of a single molecular signalling cascade, the planar cell polarity pathway, is implicated in mutants with this defect.
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Affiliation(s)
- Andrew J Copp
- Neural Development Unit, Institute of Child Health, University College London, UK.
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Weston JA, Yoshida H, Robinson V, Nishikawa S, Fraser ST, Nishikawa S. Neural crest and the origin of ectomesenchyme: neural fold heterogeneity suggests an alternative hypothesis. Dev Dyn 2004; 229:118-30. [PMID: 14699583 DOI: 10.1002/dvdy.10478] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The striking similarity between mesodermally derived fibroblasts and ectomesenchyme cells, which are thought to be derivatives of the neural crest, has long been a source of interest and controversy. In mice, the gene encoding the alpha subunit of the platelet-derived growth factor receptor (PDGFRalpha) is expressed both by mesodermally derived mesenchymal cells and by ectomesenchyme. Whole-mount immunostaining previously revealed that PDGFRalpha is present in the cephalic neural fold epithelium of early murine embryos (Takakura et al. [1997] J Histochem Cytochem 45:883-893). We now show that, within the neural fold, a sharp boundary exists between E-cadherin-expressing non-neural epithelium and the neural epithelium of the dorsal ridge. In addition, we found that cells coexpressing E-cadherin and PDGFRalpha are present in the non-neural epithelium of the neural folds. These observations raise the possibility that at least some PDGFRalpha(+) ectomesenchyme originates from the lateral non-neural domain of neural fold epithelium. This inference is consistent with previous reports (Nichols [ 1981] J Embryol Exp Morphol 64:105-120; Nichols [ 1986] Am J Anat 176:221-231) that mesenchymal cells emerge precociously from an epithelial neural fold domain resembling the primitive streak in the early embryonic epiblast. Therefore, we propose the name "metablast" for this non-neural epithelial domain to indicate that it is the site of a delayed local delamination of mesenchyme similar to involution of mesoderm during gastrulation. We further propose the testable hypothesis that neural crest and ectomesenchyme are developmentally distinct progenitor populations and that at least some ectomesenchyme is metablast-derived rather than neural crest-derived tissue. Developmental Dynamics 229:118-130, 2004.
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Affiliation(s)
- James A Weston
- Institute of Neuroscience, University of Oregon, Eugene, Oregon, USA.
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Davidson LA, Keller RE. Neural tube closure in Xenopus laevis involves medial migration, directed protrusive activity, cell intercalation and convergent extension. Development 1999; 126:4547-56. [PMID: 10498689 DOI: 10.1242/dev.126.20.4547] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have characterized the cell movements and prospective cell identities as neural folds fuse during neural tube formation in Xenopus laevis. A newly developed whole-mount, two-color fluorescent RNA in situ hybridization method, visualized with confocal microscopy, shows that the dorsal neural tube gene xpax3 and the neural-crest-specific gene xslug are expressed far lateral to the medial site of neural fold fusion and that expression moves medially after fusion. To determine whether cell movements or dynamic changes in gene expression are responsible, we used low-light videomicroscopy followed by fluorescent in situ and confocal microscopy. These methods revealed that populations of prospective neural crest and dorsal neural tube cells near the lateral margin of the neural plate at the start of neurulation move to the dorsal midline using distinctive forms of motility. Before fold fusion, superficial neural cells apically contract, roll the neural plate into a trough and appear to pull the superficial epidermal cell sheet medially. After neural fold fusion, lateral deep neural cells move medially by radially intercalating between other neural cells using two types of motility. The neural crest cells migrate as individual cells toward the dorsal midline using medially directed monopolar protrusions. These movements combine the two lateral populations of neural crest into a single medial population that form the roof of the neural tube. The remaining cells of the dorsal neural tube extend protrusions both medially and laterally bringing about radial intercalation of deep and superficial cells to form a single-cell-layered, pseudostratified neural tube. While ours is the first description of medially directed cell migration during neural fold fusion and re-establishment of the neural tube, these complex cell behaviors may be involved during cavitation of the zebrafish neural keel and secondary neurulation in the posterior axis of chicken and mouse.
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Affiliation(s)
- L A Davidson
- Department of Biology, Gilmer Hall, University of Virginia, Charlottesville, VA 22903, USA.
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