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Loukogeorgakis SP, De Coppi P. Concise Review: Amniotic Fluid Stem Cells: The Known, the Unknown, and Potential Regenerative Medicine Applications. Stem Cells 2018; 35:1663-1673. [PMID: 28009066 DOI: 10.1002/stem.2553] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 09/07/2016] [Accepted: 10/01/2016] [Indexed: 12/19/2022]
Abstract
The amniotic fluid has been identified as an untapped source of cells with broad potential, which possess immunomodulatory properties and do not have the ethical and legal limitations of embryonic stem cells. CD117(c-Kit)+ cells selected from amniotic fluid have been shown to differentiate into cell lineages representing all three embryonic germ layers without generating tumors, making them ideal candidates for regenerative medicine applications. Moreover, their ability to engraft in injured organs and modulate immune and repair responses of host tissues, suggest that transplantation of such cells may be useful for the treatment of various degenerative and inflammatory diseases. Although significant questions remain regarding the origin, heterogeneous phenotype, and expansion potential of amniotic fluid stem cells, evidence to date supports their potential role as a valuable stem cell source for the field of regenerative medicine. Stem Cells 2017;35:1663-1673.
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Affiliation(s)
- Stavros P Loukogeorgakis
- Stem Cells and Regenerative Medicine Section, Developmental Biology and Cancer Programme, Institute of Child Health, University College London, London, United Kingdom
| | - Paolo De Coppi
- Stem Cells and Regenerative Medicine Section, Developmental Biology and Cancer Programme, Institute of Child Health, University College London, London, United Kingdom
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Resca E, Zavatti M, Bertoni L, Maraldi T, De Biasi S, Pisciotta A, Nicoli A, La Sala G, Guillot P, David A, Sebire N, De Coppi P, De Pol A. Enrichment in c-Kit+ enhances mesodermal and neural differentiation of human chorionic placental cells. Placenta 2013; 34:526-35. [DOI: 10.1016/j.placenta.2013.03.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 03/25/2013] [Accepted: 03/27/2013] [Indexed: 01/15/2023]
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Yao K, Ge W. Kit System in the Zebrafish Ovary: Evidence for Functional Divergence of Two Isoforms of Kit (Kita and Kitb) and Kit Ligand (Kitlga and Kitlgb) During Folliculogenesis1. Biol Reprod 2010; 82:1216-26. [DOI: 10.1095/biolreprod.109.082644] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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De Coppi P, Bartsch G, Siddiqui MM, Xu T, Santos CC, Perin L, Mostoslavsky G, Serre AC, Snyder EY, Yoo JJ, Furth ME, Soker S, Atala A. Isolation of amniotic stem cell lines with potential for therapy. Nat Biotechnol 2007; 25:100-6. [PMID: 17206138 DOI: 10.1038/nbt1274] [Citation(s) in RCA: 1213] [Impact Index Per Article: 71.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Accepted: 11/20/2006] [Indexed: 02/07/2023]
Abstract
Stem cells capable of differentiating to multiple lineages may be valuable for therapy. We report the isolation of human and rodent amniotic fluid-derived stem (AFS) cells that express embryonic and adult stem cell markers. Undifferentiated AFS cells expand extensively without feeders, double in 36 h and are not tumorigenic. Lines maintained for over 250 population doublings retained long telomeres and a normal karyotype. AFS cells are broadly multipotent. Clonal human lines verified by retroviral marking were induced to differentiate into cell types representing each embryonic germ layer, including cells of adipogenic, osteogenic, myogenic, endothelial, neuronal and hepatic lineages. Examples of differentiated cells derived from human AFS cells and displaying specialized functions include neuronal lineage cells secreting the neurotransmitter L-glutamate or expressing G-protein-gated inwardly rectifying potassium channels, hepatic lineage cells producing urea, and osteogenic lineage cells forming tissue-engineered bone.
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Affiliation(s)
- Paolo De Coppi
- Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157-1094, USA
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Planque N, Raposo G, Leconte L, Anezo O, Martin P, Saule S. Microphthalmia Transcription Factor Induces Both Retinal Pigmented Epithelium and Neural Crest Melanocytes from Neuroretina Cells. J Biol Chem 2004; 279:41911-7. [PMID: 15277526 DOI: 10.1074/jbc.m404964200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mitf encodes a basic helix-loop-helix transcription factor that plays an essential role in the differentiation of the retinal pigmented epithelium (RPE) and neural crest-derived melanocytes. As cells containing melanogenic enzymes (TRP2) are found in Mitf mouse mutants, it is not clear whether Mitf is a downstream factor or a master regulator of melanocyte differentiation. To further study the role of Mitf in committing cells to the melanocyte lineage, we express Mitf in the cultured quail neuroretina cells. This leads to the induction of two types of pigmented cells: neural crest-derived melanocytes, according to their dendritic morphology, physiology, and gene expression pattern are observed together with pigmented epithelial RPE-like cells. The expression of Mitf is lower in pigmented epithelial RPE-like cells than in neural crest-derived melanocytes. Accordingly, overexpression of Mitf in cultured quail RPE causes cells to develop into neural crest-like pigmented cells. Thus, Mitf is sufficient for the proper differentiation of crest-like pigmented cells from retinal cells and its expression level may determine the type of pigment cell induced.
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Affiliation(s)
- Nathalie Planque
- UMR 146, Institut Curie Section de Recherche, Bātiment 110, Centre Universitaire, 91405 Orsay Cedex, France
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Hou L, Pavan WJ, Shin MK, Arnheiter H. Cell-autonomous and cell non-autonomous signaling through endothelin receptor B during melanocyte development. Development 2004; 131:3239-47. [PMID: 15201217 DOI: 10.1242/dev.01193] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The endothelin receptor B gene (Ednrb) encodes a G-protein-coupled receptor that is expressed in a variety of cell types and is specifically required for the development of neural crest-derived melanocytes and enteric ganglia. In humans, mutations in this gene are associated with Waardenburg-Shah syndrome, a disorder characterized by pigmentation defects,deafness and megacolon. To address the question of whether melanocyte development depends entirely on a cell-autonomous action of Ednrb, we performed a series of tissue recombination experiments in vitro, using neural crest cell cultures from mouse embryos carrying a novel Ednrb-null allele characterized by the insertion of a lacZ marker gene. The results show that Ednrb is not required for the generation of early neural crest-derived melanoblasts but is required for the expression of the differentiation marker tyrosinase. Tyrosinase expression can be rescued,however, by the addition of Ednrb wild-type neural tubes. These Ednrb wild-type neural tubes need not be capable of generating melanocytes themselves, but must be capable of providing KIT ligand, the cognate ligand for the tyrosine kinase receptor KIT. In fact, soluble KIT ligand is sufficient to induce tyrosinase expression in Ednrb-deficient cultures. Nevertheless, these tyrosinase-expressing, Ednrb-deficient cells do not develop to terminally differentiated,pigmented melanocytes. Pigmentation can be induced, however, by treatment with tetradecanoyl phorbol acetate, which mimics EDNRB signaling, but not by treatment with endothelin 1, which stimulates the paralogous receptor EDNRA. The results suggest that Ednrb plays a significant role during melanocyte differentiation and effects melanocyte development by both cell non-autonomous and cell-autonomous signaling mechanisms.
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Affiliation(s)
- Ling Hou
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-4472, USA.
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Wehrle-Haller B. The role of Kit-ligand in melanocyte development and epidermal homeostasis. PIGMENT CELL RESEARCH 2003; 16:287-96. [PMID: 12753403 DOI: 10.1034/j.1600-0749.2003.00055.x] [Citation(s) in RCA: 181] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Kit-ligand (Kitl) also known as steel factor, stem cell factor and mast cell growth factor plays a crucial role in the development and maintenance of the melanocyte lineage in adult skin. Kitl exerts permanent survival, proliferation and migration functions in Kit receptor-expressing melanocytes. A comprehensive overview over the differential roles of Kitl in melanocyte development and homeostasis is provided. I discuss species-specific differences of the Kitl/Kit signalling system, regulation at the transcriptional level and also covering the regulation of cell surface Kitl presentation by cytoplasmic targeting sequences. In addition, recent studies evoked the importance of Kitl misexpression in some hyperpigmented lesions that may open the avenue for Kitl-dependent treatment of pathological skin conditions.
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Reedy MV, Johnson RL, Erickson CA. The expression patterns of c-kit and Sl in chicken embryos suggest unexpected roles for these genes in somite and limb development. Gene Expr Patterns 2003; 3:53-8. [PMID: 12609603 DOI: 10.1016/s1567-133x(02)00072-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have used whole-mount in situ hybridization to investigate the patterns of c-kit and Sl expression in stage 11-22 chicken embryos. Our analysis shows that c-kit and Sl are expressed quite differently in chicken embryos compared to the reported expression patterns of these genes in embryos of other taxa. Most notably, chicken c-kit is expressed in primordial germ cells as well as in the developing somite, the apical ectodermal ridge, and in the early foregut endoderm. Sl is expressed in the lateral and intermediate mesoderm and in extraembryonic membranes. These data suggest that chicken c-kit and Sl may play novel and unexpected roles in somitogenesis, limb development, and foregut development in avian embryos.
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Affiliation(s)
- Mark V Reedy
- Section of Molecular and Cellular Biology, University of California at Davis, Davis, CA 95616, USA.
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Rich A, Miller SM, Gibbons SJ, Malysz J, Szurszewski JH, Farrugia G. Local presentation of Steel factor increases expression of c-kit immunoreactive interstitial cells of Cajal in culture. Am J Physiol Gastrointest Liver Physiol 2003; 284:G313-20. [PMID: 12388202 DOI: 10.1152/ajpgi.00093.2002] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The binding of Steel factor (SF) to c-kit initiates a signaling pathway essential for development and maintenance of interstitial cells of Cajal (ICC). Soluble and membrane-bound isoforms of SF are expressed in the gastrointestinal tract, but the role for either isoform in supporting ICC development is unknown. The aim of this study was to determine the role of SF in supporting ICC in culture. ICC were cultured from dissociated mouse jejunum and grown with fibroblast cell lines that produced either soluble, membrane-bound or membrane-restricted SF. ICC were identified and counted by c-kit immunoreactivity. The number of c-kit immunoreactive cells was greater in the coculture system compared with cultures grown without SF-producing fibroblasts. All forms of SF-producing fibroblasts increased ICC number in culture but physical separation of the fibroblasts from the c-kit immunoreactive cells, the addition of exogenous SF to the culture medium, or fibroblast-conditioned media did not. These results are consistent with the hypothesis that the membrane-bound form of SF preferentially contributes to expression of c-kit-positive ICC under cell culture conditions.
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Affiliation(s)
- Adam Rich
- Enteric NeuroScience Program, Department of Physiology and Biophysics, Mayo Clinic and Mayo Foundation, Rochester, Minnesota 55905, USA.
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Tosney KW. Long-distance cue from emerging dermis stimulates neural crest melanoblast migration. Dev Dyn 2003; 229:99-108. [PMID: 14699581 DOI: 10.1002/dvdy.10492] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Neural crest melanoblasts display unique navigational abilities enabling them to colonize the dorsal path between ectoderm and somite. One signal shown here to elicit melanoblast migration is a chemotactic cue supplied by the emerging dermis. Until dermis emerges, melanoblasts fail to enter the dorsal path. The dermis emerges from a site that is too distant to stimulate migration by cell contact. Instead, surgeries show that dermis elicits migration from a distance. When dermis is grafted distally, neural crest cells enter the path precociously. Moreover, large grafts recruit melanoblasts from the control sides (without increasing crest cell numbers) as well as a few crest cells from ventral somite. Because other grafted tissues fail to stimulate migration, the dermis stimulus is specific. This report is the first documentation that trunk neural crest cells can be guided chemotactically. It also extends evidence that migration is exquisitely sensitive to temporal-spatial patterns of somite morphogenesis. Developmental Dynamics 229:99-108, 2004.
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Affiliation(s)
- Kathryn W Tosney
- Molecular, Cellular and Developmental Biology Department and The Neuroscience Program, The University of Michigan, Ann Arbor, Michigan, USA.
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Quigley IK, Parichy DM. Pigment pattern formation in zebrafish: a model for developmental genetics and the evolution of form. Microsc Res Tech 2002; 58:442-55. [PMID: 12242701 DOI: 10.1002/jemt.10162] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The zebrafish Danio rerio is an emerging model organism for understanding vertebrate development and genetics. One trait of both historical and recent interest is the pattern formed by neural crest-derived pigment cells, or chromatophores, which include black melanophores, yellow xanthophores, and iridescent iridophores. In zebrafish, an embryonic and early larval pigment pattern consists of several stripes of melanophores and iridophores, whereas xanthophores are scattered widely over the flank. During metamorphosis, however, this pattern is transformed into that of the adult, which comprises several dark stripes of melanophores and iridophores that alternate with light stripes of xanthophores and iridophores. In this review, we place zebrafish relative to other model and non-model species; we review what is known about the processes of chromatophore specification, differentiation, and morphogenesis during the development of embryonic and adult pigment patterns, and we address how future studies of zebrafish will likely aid our understanding of human disease and the evolution of form.
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Affiliation(s)
- Ian K Quigley
- Section of Integrative Biology, University of Texas at Austin, 78712, USA
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Welker P, Schadendorf D, Artuc M, Grabbe J, Henz BM. Expression of SCF splice variants in human melanocytes and melanoma cell lines: potential prognostic implications. Br J Cancer 2000; 82:1453-8. [PMID: 10780526 PMCID: PMC2363371 DOI: 10.1054/bjoc.1999.1076] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Stem cell factor (SCF), the ligand for c-Kit, is known to regulate developmental and functional processes of haematopoietic stem cells, mast cells and melanocytes. Two different splice variants form predominantly soluble (sSCF or SCF-1) and in addition some membrane-bound SCF (mSCF or SCF-2). In order to explore the prognostic significance of these molecules in melanoma, total SCF, SCF splice variants and c-Kit expression were studied in normal skin melanocytes and in 11 different melanoma cell lines, using reverse transcription polymerase chain reaction, immunocytochemistry and enzyme-linked immunosorbent assay. Nine of the 11 melanoma cell lines expressed SCF-1 mRNA, only two of them SCF-2, and these two also SCF-1. Coexpression of both SCF-1 and c-Kit was noted in five cell lines, and only one cell line as well as normal melanocytes expressed both SCF-1 and SCF-2 as well as c-Kit. Corresponding results were obtained on immunocytochemical staining. Of three exemplary melanoma cell lines studied, two expressing SCF mRNA also released SCF spontaneously and on stimulation, whereas the line lacking SCF and c-kit mRNA (SK-Mel-23) failed to do so. These data demonstrate thus that melanoma cell lines, particularly those known to metastasize in vivo, lose the ability to express SCF-2 mRNA, suggesting that this molecule may serve, next to c-Kit, as a prognostic marker for malignant melanoma.
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Affiliation(s)
- P Welker
- Department of Dermatology, Charité, Humboldt University, Berlin, Germany
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Rice J, Doggett B, Sweetser DA, Yanagisawa H, Yanagisawa M, Kapur RP. Transgenic rescue of aganglionosis and piebaldism in lethal spotted mice. Dev Dyn 2000; 217:120-32. [PMID: 10679935 DOI: 10.1002/(sici)1097-0177(200001)217:1<120::aid-dvdy11>3.0.co;2-u] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Complete colonization of the gut by enteric neural precursors depends on activation of ednrB and Ret receptors by their respective ligands, edn3 and gdnf. Mutations that eliminate expression of either ligand or either receptor produce intestinal aganglionosis in rodents and humans. Embryos homozygous for the lethal spotted (ls) allele, a loss of function mutation in the edn3 gene, have no ganglion cells in their terminal large intestines and are spotted, due to incomplete colonization of the skin by melanocyte precursors. Expression of edn3 in enteric neural precursors of transgenic mice compensates fully for deficient endogenous edn3 in ls/ls embryos. The effects of the edn3 transgene are dose-dependent, as lower levels of expression in one line prevent aganglionosis in only a subset of animals and reduce, but fail to eliminate, piebaldism. In contrast, expression of neither constitutively active Ret nor activated ras in enteric neural progenitors alters the severity of aganglionosis or piebaldism in ls/ls mice. Given the spatial and temporal pattern of edn3-transgene expression, our results suggest that edn3/ednrB signals are not required prior to the arrival of crest cells in the gut and endrB stimulation elicits distinct cellular responses from Ret or ras activation. Dev Dyn 2000;217:120-132.
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Affiliation(s)
- J Rice
- Department of Pathology, University of Washington, Seattle, WA 98195, USA
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Beauvais-Jouneau A, Pla P, Bernex F, Dufour S, Salamero J, Fässler R, Panthier JJ, Thiery JP, Larue L. A novel model to study the dorsolateral migration of melanoblasts. Mech Dev 1999; 89:3-14. [PMID: 10559475 DOI: 10.1016/s0925-4773(99)00191-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Melanocytes derived from pluripotent neural crest cells migrate initially in the dorsolateral pathway between the ectoderm and dermomyotome. To understand the role of specific proteins involved in this cell migration, we looked for a cellular model that mimics the in vivo behavior of melanoblasts, and that allows functional studies of their migration. We report here that wild-type embryonic stem (ES) cells are able to follow the ventral and dorsolateral neural crest pathways after being grafted into chicken embryos. By contrast, a mutant ES cell line deficient for beta1 integrin subunits, proteins involved in cell-extracellular interactions, had a severely impaired migratory behavior. Interestingly, ES cells deficient for Kit, the tyrosine kinase receptor for the stem cell factor (SCF), behaved similarly to wild-type ES cells. Thus, grafting mouse ES cells into chicken embryos provides a new cellular system that allows both in vitro and in vivo studies of the molecular mechanisms controlling dorsolateral migration.
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Affiliation(s)
- A Beauvais-Jouneau
- Developmental Genetics of Melanocytes, UMR 146 CNRS-Institut Curie, Bat. 110, 91405, Orsay, France
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Parichy DM, Rawls JF, Pratt SJ, Whitfield TT, Johnson SL. Zebrafish sparse corresponds to an orthologue of c-kit and is required for the morphogenesis of a subpopulation of melanocytes, but is not essential for hematopoiesis or primordial germ cell development. Development 1999; 126:3425-36. [PMID: 10393121 DOI: 10.1242/dev.126.15.3425] [Citation(s) in RCA: 211] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The relative roles of the Kit receptor in promoting the migration and survival of amniote melanocytes are unresolved. We show that, in the zebrafish, Danio rerio, the pigment pattern mutation sparse corresponds to an orthologue of c-kit. This finding allows us to further elucidate morphogenetic roles for this c-kit-related gene in melanocyte morphogenesis. Our analyses of zebrafish melanocyte development demonstrate that the c-kit orthologue identified in this study is required both for normal migration and for survival of embryonic melanocytes. We also find that, in contrast to mouse, the zebrafish c-kit gene that we have identified is not essential for hematopoiesis or primordial germ cell development. These unexpected differences may reflect evolutionary divergence in c-kit functions following gene duplication events in teleosts.
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Affiliation(s)
- D M Parichy
- Department of Genetics, Washington University School of Medicine, Box 8232, St Louis, MO 63110, USA.
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Lauffenburger DA, Oehrtman GT, Walker L, Wiley HS. Real-time quantitative measurement of autocrine ligand binding indicates that autocrine loops are spatially localized. Proc Natl Acad Sci U S A 1998; 95:15368-73. [PMID: 9860975 PMCID: PMC28049 DOI: 10.1073/pnas.95.26.15368] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/1998] [Accepted: 10/15/1998] [Indexed: 11/18/2022] Open
Abstract
Autocrine ligands are important regulators of many normal tissues and have been implicated in a number of disease states, including cancer. However, because by definition autocrine ligands are synthesized, secreted, and bound to cell receptors within an intrinsically self-contained "loop," standard pharmacological approaches cannot be used to investigate relationships between ligand/receptor binding and consequent cellular responses. We demonstrate here a new approach for measurement of autocrine ligand binding to cells, using a microphysiometer assay originally developed for investigating cell responses to exogenous ligands. This technique permits quantitative measurements of autocrine responses on the time scale of receptor binding and internalization, thus allowing investigation of the role of receptor trafficking and dynamics in cellular responses. We used this technique to investigate autocrine signaling through the epidermal growth factor receptor by transforming growth factor alpha (TGFalpha) and found that anti-receptor antibodies are far more effective than anti-ligand antibodies in inhibiting autocrine signaling. This result indicates that autocrine-based signals can operate in a spatially restricted, local manner and thus provide cells with information on their local microenvironment.
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Affiliation(s)
- D A Lauffenburger
- Division of Bioengineering & Environmental Health and Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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Erickson CA, Reedy MV. Neural crest development: the interplay between morphogenesis and cell differentiation. Curr Top Dev Biol 1998; 40:177-209. [PMID: 9673851 DOI: 10.1016/s0070-2153(08)60367-1] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The final pattern of tissues established during embryogenesis reflects the outcome of two developmental processes: differentiation and morphogenesis. Avian neural crest cells are an excellent system in which to study this interaction. In the first phase of neural crest cell migration, neural crest cells separate from the neural epithelium via an epithelial-mesenchymal transformation. We present three models to account for this process: (1) separation by asymmetric mitosis, (2) separation by generating tractional force in order to rupture cell adhesions and (3) loss of expression or function of cell-cell adhesion molecules that keep the presumptive neural crest cells tethered to the neural epithelium. Evidence is presented that the segregation of the neural crest lineage apart from the neural epithelium is caused by the epithelial-mesenchymal transformation. Once they have detached from the neural tube, neural crest cells take two pathways in the trunk of the chick embryo: (1) the ventral path between the neural tube and somite, where neural crest cells give rise to neurons and glial cells of the peripheral nervous systems, and (2) the dorsolateral path between the ectoderm and dermamyotome of the somite, where they differentiate into pigment cells of the skin. We present data to suggest that the migration and differentiation along the ventral path is controlled primarily by environmental cues, which we refer to as the environment-directed model of neural crest morphogenesis. Conversely, only melanoblasts can migrate into the dorsolateral space, and the ability to invade that path is dependent upon their early specification as melanoblasts. We call this the phenotype-directed model for neural crest cell migration and suggest that this latter model for the positioning of neural crest derivatives in the embryo may be more common than previously suspected. These observations invite a re-examination of patterning of other crest derivates, which previously were believed to be controlled by environmental cues.
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Affiliation(s)
- C A Erickson
- Section of Molecular and Cellular Biology, University of California-Davis 95616, USA
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