Multi-Photon Time Lapse Imaging to Visualize Development in Real-time: Visualization of Migrating Neural Crest Cells in Zebrafish Embryos

Abstract Objectives Vitamin E (VitE) deficiency causes vertebrate embryonic lethality. The alpha-tocopherol transfer protein (Ttpa) likely regulates VitE distribution in the early zebrafish embryo because Ttpa knockdown causes impaired nervous system development and embryonic death by 15–18 hours post-fertilization (hpf). We propose that VitE is necessary for normal brain and peripheral nervous system development. Methods Zebrafish embryos are obtained from adults fed either VitE sufficient (E+) or deficient (E–) diets for at least 80 days. Embryos at 12 and 24 hpf are subjected to RNA whole mount in situ hybridization (WISH). RNA is also collected from embryos at 12, 18 and 24 hpf for RT-qPCR of specific targets. Results At 12 hpf, the midbrain-hindbrain boundary and otic placodes are malformed in E– embryos, as shown by Pax2a expression. Similarly, Sox10 expression shows that E– embryos lack clear neural plate borders. Nonetheless, in 12 hpf E + and E− embryos Ttpa is localized similarly throughout the nervous system. Pax2a expression initiates collagen formation in the developing notochord. Collagen genes, col2a1a and col9a2, expression patterns showed abnormal notochord structures in 24 hpf E– embryos. At 24 hpf in E + embryos, Sox10 expressing-neural crest cells are localized both in the central nervous system and dorsal root ganglia (DRG), while the Sox10 signal is diminished in E– embryos in both the DRG and early enteric nervous system. At 24 hpf, Ttpa expression outlines the brain ventricle borders; critically E– embryos show reduced Ttpa signal and impaired ventricle closing. Gene expression by qPCR will be used to confirm these results. Conclusions This VitE deficient embryo model suggests that the carefully programmed development of the nervous system is distorted due to lack of adequate VitE. Thus, Ttpa and VitE are critical molecules for neural plate and neural tube formation, and neural crest cell migration. Funding Sources The authors received no specific funding for this work.

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The hypoxia factor Hif-1α controls neural crest chemotaxis and epithelial to mesenchymal transition

The Journal of Cell Biology ◽

10.1083/jcb.201212100 ◽

2013 ◽

Vol 201 (5) ◽

pp. 759-776 ◽

Cited By ~ 74

Author(s):

Elias H. Barriga ◽

Patrick H. Maxwell ◽

Ariel E. Reyes ◽

Roberto Mayor

Keyword(s):

Neural Crest ◽

Cancer Metastasis ◽

Epithelial To Mesenchymal Transition ◽

Neural Crest Cells ◽

Embryonic Cell ◽

Zebrafish Embryos ◽

Mesenchymal Transition ◽

Metastasis Inhibition ◽

Neural Crest Migration ◽

Transcription Factor 1

One of the most important mechanisms that promotes metastasis is the stabilization of Hif-1 (hypoxia-inducible transcription factor 1). We decided to test whether Hif-1α also was required for early embryonic development. We focused our attention on the development of the neural crest, a highly migratory embryonic cell population whose behavior has been likened to cancer metastasis. Inhibition of Hif-1α by antisense morpholinos in Xenopus laevis or zebrafish embryos led to complete inhibition of neural crest migration. We show that Hif-1α controls the expression of Twist, which in turn represses E-cadherin during epithelial to mesenchymal transition (EMT) of neural crest cells. Thus, Hif-1α allows cells to initiate migration by promoting the release of cell–cell adhesions. Additionally, Hif-1α controls chemotaxis toward the chemokine SDF-1 by regulating expression of its receptor Cxcr4. Our results point to Hif-1α as a novel and key regulator that integrates EMT and chemotaxis during migration of neural crest cells.

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139A: REAL TIME FATE MAPPING OF CRANIAL NEURAL CREST CELLS DURING PALATOGENESIS IN THE SOX10: KAEDE ZEBRAFISH MODEL

Plastic & Reconstructive Surgery ◽

10.1097/01.prs.0000371873.65459.55 ◽

2010 ◽

Vol 125 (Supplement) ◽

pp. 93

Author(s):

GJ Hickey ◽

E Curtin ◽

AJ Davidson ◽

EC Liao

Keyword(s):

Neural Crest ◽

Real Time ◽

Neural Crest Cells ◽

Fate Mapping ◽

Cranial Neural Crest ◽

Zebrafish Model ◽

Cranial Neural Crest Cells

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Significance of cell-to-cell contacts for the directional movement of neural crest cells within a hydrated collagen lattice

Development ◽

10.1242/dev.63.1.29 ◽

1981 ◽

Vol 63 (1) ◽

pp. 29-51

Author(s):

Edward M. Davis ◽

J. P. Trinkaus

Keyword(s):

Neural Crest ◽

Neural Tube ◽

Average Rate ◽

Single Cells ◽

Neural Crest Cells ◽

Time Lapse ◽

Contact Inhibition ◽

Neural Tubes ◽

Directional Movement ◽

Contact Behaviour

Neural tubes whose neural crest had just begun migration were isolated from stage-14 chick embryos, cleaned with 0·1 % trypsin, and cultured in transparent hydrated collagen lattices (HCL) in an effort to stimulate in part the three-dimensional environment through which neural crest cells migrate in situ, in the embryo. The concentration of collagen in the lattices varied from 50µg/ml to 390µg/ml. The mode of movement and contact behaviour of neural crest cells migrating from the neural tube under these conditions were recorded directly with time-lapse cinemicrography. Both their shape and their rate of translocation were dependent on the concentration of collagen in the HCL. In low concentrations (50 µg/ ml to 105 µg/ml), neural crest cells have elongate spindle shapes and translocate at an average rate of 1 µm/min, whereas in high concentrations (190µg/ml to 390µg/ml), their shape is rounded, and they translocate at an average rate of only 0·5µm/min. Neural crest cells migrate from neural tubes in these preparations principally in loose clusters, with a few single cells in the lead. The cells in these groups display leading-to-trailing edge adhesions and form tongues or streams of cells directed away from the neural tube. The paths of migration of both individual cells and groups of cells are aligned with the collagen fibrils of the HCL, which radiate from the neural tube. The classical visible characteristic of contact inhibition of movement, change in direction of cell movement after contact with other! cells, was not observed; neither the rate of translocation nor the time spent migrating away from the tube is dependent on the number of contacts between cells. It is concluded that the directional movement of neural crest cells in HCL cultures does not depend on contact inhibition of movement.

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Translocation of neural crest cells within a hydrated collagen lattice

Development ◽

10.1242/dev.55.1.17 ◽

1980 ◽

Vol 55 (1) ◽

pp. 17-31

Author(s):

Edward M. Davis

Keyword(s):

Neural Crest ◽

Growth Medium ◽

Neural Tube ◽

Average Rate ◽

Neural Crest Cells ◽

Time Lapse ◽

Culture Conditions ◽

Serum Free ◽

Neural Tubes ◽

Collagen Lattice

Chick neural tubes were cultured either on planar substrata of collagen-coated Falcon plastic in growth medium with serum or within a hydrated collagen lattice (HCL) in growth medium either with or without serum. Using time-lapse cinemicrography, neural crest cells were observed emigrating from neural tubes over the collagen substrata. Once separated from the neural tube, they seldom reunite with it. Though the average rate at which the neural crest cells translocate was the same in the different culture conditions, approximately l·0 μm/min, distinct differences in morphology and mode of translocation were observed. Neural crest cells on collagen-coated culture dishes have a flattened fibroblastic morphology and mode of translocation; in an HC1 with serum, they have a bipolar shape and translocate by advancing a long, narrow leading protrusion and by periodically retracting the attenuated trailing portion of the cell; and in a serum-free HCL, they have a unipolar shape and translocate by advancing a long, narrow, branched leading protrusion and by periodically transferring the cytoplasm of the large, rounded trailing cell body forward, past a bulbous structure, and into the leading protrusion.

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