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Janssen R, Budd GE. New insights into mesoderm and endoderm development, and the nature of the onychophoran blastopore. Front Zool 2024; 21:2. [PMID: 38267986 PMCID: PMC10809584 DOI: 10.1186/s12983-024-00521-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 01/09/2024] [Indexed: 01/26/2024] Open
Abstract
BACKGROUND Early during onychophoran development and prior to the formation of the germ band, a posterior tissue thickening forms the posterior pit. Anterior to this thickening forms a groove, the embryonic slit, that marks the anterior-posterior orientation of the developing embryo. This slit is by some authors considered the blastopore, and thus the origin of the endoderm, while others argue that the posterior pit represents the blastopore. This controversy is of evolutionary significance because if the slit represents the blastopore, then this would support the amphistomy hypothesis that suggests that a slit-like blastopore in the bilaterian ancestor evolved into protostomy and deuterostomy. RESULTS In this paper, we summarize our current knowledge about endoderm and mesoderm development in onychophorans and provide additional data on early endoderm- and mesoderm-determining marker genes such as Blimp, Mox, and the T-box genes. CONCLUSION We come to the conclusion that the endoderm of onychophorans forms prior to the development of the embryonic slit, and thus that the slit is not the primary origin of the endoderm. It is thus unlikely that the embryonic slit represents the blastopore. We suggest instead that the posterior pit indeed represents the lips of the blastopore, and that the embryonic slit (and surrounding tissue) represents a morphologically superficial archenteron-like structure. We conclude further that both endoderm and mesoderm development are under control of conserved gene regulatory networks, and that many of the features found in arthropods including the model Drosophila melanogaster are likely derived.
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Affiliation(s)
- Ralf Janssen
- Department of Earth Sciences, Palaeobiology, Uppsala University, Villavägen 16, 75236, Uppsala, Sweden.
| | - Graham E Budd
- Department of Earth Sciences, Palaeobiology, Uppsala University, Villavägen 16, 75236, Uppsala, Sweden
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2
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Tingler M, Brugger A, Feistel K, Schweickert A. dmrt2 and myf5 Link Early Somitogenesis to Left-Right Axis Determination in Xenopus laevis. Front Cell Dev Biol 2022; 10:858272. [PMID: 35813209 PMCID: PMC9260042 DOI: 10.3389/fcell.2022.858272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 05/03/2022] [Indexed: 12/18/2022] Open
Abstract
The vertebrate left-right axis is specified during neurulation by events occurring in a transient ciliated epithelium termed left-right organizer (LRO), which is made up of two distinct cell types. In the axial midline, central LRO (cLRO) cells project motile monocilia and generate a leftward fluid flow, which represents the mechanism of symmetry breakage. This directional fluid flow is perceived by laterally positioned sensory LRO (sLRO) cells, which harbor non-motile cilia. In sLRO cells on the left side, flow-induced signaling triggers post-transcriptional repression of the multi-pathway antagonist dand5. Subsequently, the co-expressed Tgf-β growth factor Nodal1 is released from Dand5-mediated repression to induce left-sided gene expression. Interestingly, Xenopus sLRO cells have somitic fate, suggesting a connection between LR determination and somitogenesis. Here, we show that doublesex and mab3-related transcription factor 2 (Dmrt2), known to be involved in vertebrate somitogenesis, is required for LRO ciliogenesis and sLRO specification. In dmrt2 morphants, misexpression of the myogenic transcription factors tbx6 and myf5 at early gastrula stages preceded the misspecification of sLRO cells at neurula stages. myf5 morphant tadpoles also showed LR defects due to a failure of sLRO development. The gain of myf5 function reintroduced sLRO cells in dmrt2 morphants, demonstrating that paraxial patterning and somitogenesis are functionally linked to LR axis formation in Xenopus.
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Della Gaspera B, Weill L, Chanoine C. Evolution of Somite Compartmentalization: A View From Xenopus. Front Cell Dev Biol 2022; 9:790847. [PMID: 35111756 PMCID: PMC8802780 DOI: 10.3389/fcell.2021.790847] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 11/26/2021] [Indexed: 11/13/2022] Open
Abstract
Somites are transitory metameric structures at the basis of the axial organization of vertebrate musculoskeletal system. During evolution, somites appear in the chordate phylum and compartmentalize mainly into the dermomyotome, the myotome, and the sclerotome in vertebrates. In this review, we summarized the existing literature about somite compartmentalization in Xenopus and compared it with other anamniote and amniote vertebrates. We also present and discuss a model that describes the evolutionary history of somite compartmentalization from ancestral chordates to amniote vertebrates. We propose that the ancestral organization of chordate somite, subdivided into a lateral compartment of multipotent somitic cells (MSCs) and a medial primitive myotome, evolves through two major transitions. From ancestral chordates to vertebrates, the cell potency of MSCs may have evolved and gave rise to all new vertebrate compartments, i.e., the dermomyome, its hypaxial region, and the sclerotome. From anamniote to amniote vertebrates, the lateral MSC territory may expand to the whole somite at the expense of primitive myotome and may probably facilitate sclerotome formation. We propose that successive modifications of the cell potency of some type of embryonic progenitors could be one of major processes of the vertebrate evolution.
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Janssen R, Pechmann M, Turetzek N. A chelicerate Wnt gene expression atlas: novel insights into the complexity of arthropod Wnt-patterning. EvoDevo 2021; 12:12. [PMID: 34753512 PMCID: PMC8579682 DOI: 10.1186/s13227-021-00182-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Accepted: 10/27/2021] [Indexed: 11/24/2022] Open
Abstract
The Wnt genes represent a large family of secreted glycoprotein ligands that date back to early animal evolution. Multiple duplication events generated a set of 13 Wnt families of which 12 are preserved in protostomes. Embryonic Wnt expression patterns (Wnt-patterning) are complex, representing the plentitude of functions these genes play during development. Here, we comprehensively investigated the embryonic expression patterns of Wnt genes from three species of spiders covering both main groups of true spiders, Haplogynae and Entelegynae, a mygalomorph species (tarantula), as well as a distantly related chelicerate outgroup species, the harvestman Phalangium opilio. All spiders possess the same ten classes of Wnt genes, but retained partially different sets of duplicated Wnt genes after whole genome duplication, some of which representing impressive examples of sub- and neo-functionalization. The harvestman, however, possesses a more complete set of 11 Wnt genes but with no duplicates. Our comprehensive data-analysis suggests a high degree of complexity and evolutionary flexibility of Wnt-patterning likely providing a firm network of mutational protection. We discuss the new data on Wnt gene expression in terms of their potential function in segmentation, posterior elongation, and appendage development and critically review previous research on these topics. We conclude that earlier research may have suffered from the absence of comprehensive gene expression data leading to partial misconceptions about the roles of Wnt genes in development and evolution.
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Affiliation(s)
- Ralf Janssen
- Department of Earth Sciences, Palaeobiology, Uppsala University, Villavägen 16, 75236, Uppsala, Sweden.
| | - Matthias Pechmann
- Department of Developmental Biology, Biocenter, Institute for Zoology, University of Cologne, Zuelpicher Str. 47b, 50674, Cologne, Germany
| | - Natascha Turetzek
- Evolutionary Ecology, Faculty of Biology, Ludwig-Maximilians Universität München, Grosshaderner Strasse 2, 82152, Biozentrum, Germany
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5
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Bruce AEE, Winklbauer R. Brachyury in the gastrula of basal vertebrates. Mech Dev 2020; 163:103625. [PMID: 32526279 DOI: 10.1016/j.mod.2020.103625] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 05/11/2020] [Accepted: 06/03/2020] [Indexed: 12/20/2022]
Abstract
The Brachyury gene encodes a transcription factor that is conserved across all animals. In non-chordate metazoans, brachyury is primarily expressed in ectoderm regions that are added to the endodermal gut during development, and often form a ring around the site of endoderm internalization in the gastrula, the blastopore. In chordates, this brachyury ring is conserved, but the gene has taken on a new role in the formation of the mesoderm. In this phylum, a novel type of mesoderm that develops into notochord and somites has been added to the ancestral lateral plate mesoderm. Brachyury contributes to a shift in cell fate from neural ectoderm to posterior notochord and somites during a major lineage segregation event that in Xenopus and in the zebrafish takes place in the early gastrula. In the absence of this brachyury function, impaired formation of posterior mesoderm indirectly affects the gastrulation movements of peak involution and convergent extension. These movements are confined to specific regions and stages, leaving open the question why brachyury expression in an extensive, coherent ring, before, during and after gastrulation, is conserved in the two species whose gastrulation modes differ considerably, and also in many other metazoan gastrulae of diverse structure.
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Affiliation(s)
- Ashley E E Bruce
- Department of Cell and Systems Biology, University of Toronto, Canada
| | - Rudolf Winklbauer
- Department of Cell and Systems Biology, University of Toronto, Canada.
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Human and mouse studies establish TBX6 in Mendelian CAKUT and as a potential driver of kidney defects associated with the 16p11.2 microdeletion syndrome. Kidney Int 2020; 98:1020-1030. [PMID: 32450157 DOI: 10.1016/j.kint.2020.04.045] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 03/03/2020] [Accepted: 04/09/2020] [Indexed: 12/22/2022]
Abstract
Congenital anomalies of the kidney and urinary tract (CAKUTs) are the most common cause of chronic kidney disease in children. Human 16p11.2 deletions have been associated with CAKUT, but the responsible molecular mechanism remains to be illuminated. To explore this, we investigated 102 carriers of 16p11.2 deletion from multi-center cohorts, among which we retrospectively ascertained kidney morphologic and functional data from 37 individuals (12 Chinese and 25 Caucasian/Hispanic). Significantly higher CAKUT rates were observed in 16p11.2 deletion carriers (about 25% in Chinese and 16% in Caucasian/Hispanic) than those found in the non-clinically ascertained general populations (about 1/1000 found at autopsy). Furthermore, we identified seven additional individuals with heterozygous loss-of-function variants in TBX6, a gene that maps to the 16p11.2 region. Four of these seven cases showed obvious CAKUT. To further investigate the role of TBX6 in kidney development, we engineered mice with mutated Tbx6 alleles. The Tbx6 heterozygous null (i.e., loss-of-function) mutant (Tbx6+/‒) resulted in 13% solitary kidneys. Remarkably, this incidence increased to 29% in a compound heterozygous model (Tbx6mh/‒) that reduced Tbx6 gene dosage to below haploinsufficiency, by combining the null allele with a novel mild hypomorphic allele (mh). Renal hypoplasia was also frequently observed in these Tbx6-mutated mouse models. Thus, our findings in patients and mice establish TBX6 as a novel gene involved in CAKUT and its gene dosage insufficiency as a potential driver for kidney defects observed in the 16p11.2 microdeletion syndrome.
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Loreti M, Shi DL, Carron C. The regulatory proteins DSCR6 and Ezh2 oppositely regulate Stat3 transcriptional activity in mesoderm patterning during Xenopus development. J Biol Chem 2020; 295:2724-2735. [PMID: 31996376 DOI: 10.1074/jbc.ra119.010719] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 01/15/2020] [Indexed: 12/26/2022] Open
Abstract
Embryonic cell fate specification and axis patterning requires integration of several signaling pathways that orchestrate region-specific gene expression. The transcription factor signal transducer and activator of transcription 3 (Stat3) plays important roles during early development, but it is unclear how Stat3 is activated. Here, using Xenopus as a model, we analyzed the post-translational regulation and functional consequences of Stat3 activation in dorsoventral axis patterning. We show that Stat3 phosphorylation, lysine methylation, and transcriptional activity increase before gastrulation and induce ventral mesoderm formation. Down syndrome critical region gene 6 (DSCR6), a RIPPLY family member that induces dorsal mesoderm by releasing repressive polycomb group proteins from chromatin, bound to the Stat3 C-terminal region and antagonized its transcriptional and ventralizing activities by interfering with its lysine methylation. Enhancer of zeste 2 polycomb-repressive complex 2 subunit (Ezh2) also bound to this region; however, its methyltransferase activity was required for Stat3 methylation and activation. Loss of Ezh2 resulted in dorsalization of ventral mesoderm and formation of a secondary axis. Furthermore, interference with Ezh2 phosphorylation also prevented Stat3 lysine methylation and transcriptional activity. Thus, inhibition of either Ezh2 phosphorylation or Stat3 lysine methylation compensated for the absence of DSCR6 function. These results reveal that DSCR6 and Ezh2 critically and post-translationally regulate Stat3 transcriptional activity. Ezh2 promotes Stat3 activation in ventral mesoderm formation independently of epigenetic regulation, whereas DSCR6 specifies dorsal fate by counteracting this ventralizing activity. This antagonism helps pattern the mesoderm along the dorsoventral axis, representing a critical facet of cell identity regulation during development.
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Affiliation(s)
- Mafalda Loreti
- Sorbonne Université, CNRS UMR7622, IBPS-Developmental Biology Laboratory, 75005 Paris, France
| | - De-Li Shi
- Sorbonne Université, CNRS UMR7622, IBPS-Developmental Biology Laboratory, 75005 Paris, France.
| | - Clémence Carron
- Sorbonne Université, CNRS UMR7622, IBPS-Developmental Biology Laboratory, 75005 Paris, France.
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8
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Cheng XN, Shao M, Shi DL. Collagen triple helix repeat containing 1a (Cthrc1a) regulates cell adhesion and migration during gastrulation in zebrafish. Exp Cell Res 2019; 381:112-120. [DOI: 10.1016/j.yexcr.2019.04.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/08/2019] [Accepted: 04/29/2019] [Indexed: 01/27/2023]
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Mutational analysis of dishevelled genes in zebrafish reveals distinct functions in embryonic patterning and gastrulation cell movements. PLoS Genet 2018; 14:e1007551. [PMID: 30080849 PMCID: PMC6095615 DOI: 10.1371/journal.pgen.1007551] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 08/16/2018] [Accepted: 07/10/2018] [Indexed: 12/31/2022] Open
Abstract
Wnt signaling plays critical roles in dorsoventral fate specification and anteroposterior patterning, as well as in morphogenetic cell movements. Dishevelled proteins, or Dvls, mediate the activation of Wnt/ß-catenin and Wnt/planar cell polarity pathways. There are at least three highly conserved Dvl proteins in vertebrates, but the implication of each Dvl in key early developmental processes remains poorly understood. In this study, we use genome-editing approach to generate different combinations of maternal and zygotic dvl mutants in zebrafish, and examine their functions during early development. Maternal transcripts for dvl2 and dvl3a are most abundantly expressed, whereas the transcript levels of other dvl genes are negligible. Phenotypic and molecular analyses show that early dorsal fate specification is not affected in maternal and zygotic dvl2 and dvl3a double mutants, suggesting that the two proteins may be dispensable for the activation of maternal Wnt/ß-catenin signaling. Interestingly, convergence and extension movements and anteroposterior patterning require both maternal and the zygotic functions of Dvl2 and Dvl3a, but these processes are more sensitive to Dvl2 dosage. Zygotic dvl2 and dvl3a double mutants display mild axis extension defect with correct anteroposterior patterning. However, maternal and zygotic double mutants exhibit most strongly impaired convergence and extension movements, severe trunk and posterior deficiencies, and frequent occurrence of cyclopia and craniofacial defects. Our results suggest that Dvl2 and Dvl3a products are required for the activation of zygotic Wnt/ß-catenin signaling and Wnt/planar cell polarity pathway, and regulate zygotic developmental processes in a dosage-dependent manner. This work provides insight into the mechanisms of Dvl-mediated Wnt signaling pathways during early vertebrate development. The embryogenesis of most animals is first supported by maternal gene products accumulated in the oocyte, and then by the expression of genes from the zygote. In all vertebrates, there are at least three Dishevelled (Dvl) proteins, which play critical roles in normal development and human diseases. They are both maternally and zygotically expressed, and can activate the ß-catenin-dependent Wnt pathway that regulates gene expression and cell fate, and the ß-catenin-independent Wnt pathway that orchestrates cell movements. In zebrafish embryo, Dvl2 and Dvl3a are most abundant, but their functions are not fully understood. We find that maternally and zygotically expressed Dvl2 plays a predominant role in the elongation of the anteroposterior axis, and the expression of genes involved in the development of the posterior region. Dvl3a cooperates with Dvl2 in these processes. Analyses after loss-of-function of these genes indicate that deficiency of maternal and zygotic Dvl2 and Dvl3a results in embryos with cyclopia, craniofacial defects, and severe abnormality in the trunk and posterior regions. Many human birth defects and other diseases, like cancer, are attributed to the dysfunction of the Wnt pathways. Our results help to understand the mechanisms of Dvl-mediated Wnt pathway activation, and the causes of developmental disorders.
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Castro Colabianchi AM, Revinski DR, Encinas PI, Baez MV, Monti RJ, Rodríguez Abinal M, Kodjabachian L, Franchini LF, López SL. Notch1 is asymmetrically distributed from the beginning of embryogenesis and controls the ventral center. Development 2018; 145:dev.159368. [PMID: 29866901 DOI: 10.1242/dev.159368] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 05/25/2018] [Indexed: 12/14/2022]
Abstract
Based on functional evidence, we have previously demonstrated that early ventral Notch1 activity restricts dorsoanterior development in Xenopus We found that Notch1 has ventralizing properties and abolishes the dorsalizing activity of β-catenin by reducing its steady state levels, in a process that does not require β-catenin phosphorylation by glycogen synthase kinase 3β. In the present work, we demonstrate that Notch1 mRNA and protein are enriched in the ventral region from the beginning of embryogenesis in Xenopus This is the earliest sign of ventral development, preceding the localized expression of wnt8a, bmp4 and Ventx genes in the ventral center and the dorsal accumulation of nuclear β-catenin. Knockdown experiments indicate that Notch1 is necessary for the normal expression of genes essential for ventral-posterior development. These results indicate that during early embryogenesis ventrally located Notch1 promotes the development of the ventral center. Together with our previous evidence, these results suggest that ventral enrichment of Notch1 underlies the process by which Notch1 participates in restricting nuclear accumulation of β-catenin to the dorsal side.
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Affiliation(s)
- Aitana M Castro Colabianchi
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Biología Celular y Neurociencias 'Prof. E. De Robertis' (IBCN), Facultad de Medicina. Laboratorio de Embriología Molecular 'Prof. Dr. Andrés E. Carrasco', C1121ABG Buenos Aires, Argentina
| | - Diego R Revinski
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Biología Celular y Neurociencias 'Prof. E. De Robertis' (IBCN), Facultad de Medicina. Laboratorio de Embriología Molecular 'Prof. Dr. Andrés E. Carrasco', C1121ABG Buenos Aires, Argentina.,Aix Marseille Université, CNRS, IBDM, 13288 Marseille, France
| | - Paula I Encinas
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Biología Celular y Neurociencias 'Prof. E. De Robertis' (IBCN), Facultad de Medicina. Laboratorio de Embriología Molecular 'Prof. Dr. Andrés E. Carrasco', C1121ABG Buenos Aires, Argentina
| | - María Verónica Baez
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Biología Celular y Neurociencias 'Prof. E. De Robertis' (IBCN), Facultad de Medicina. Laboratorio de Embriología Molecular 'Prof. Dr. Andrés E. Carrasco', C1121ABG Buenos Aires, Argentina
| | - Renato J Monti
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Biología Celular y Neurociencias 'Prof. E. De Robertis' (IBCN), Facultad de Medicina. Laboratorio de Embriología Molecular 'Prof. Dr. Andrés E. Carrasco', C1121ABG Buenos Aires, Argentina
| | - Mateo Rodríguez Abinal
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Biología Celular y Neurociencias 'Prof. E. De Robertis' (IBCN), Facultad de Medicina. Laboratorio de Embriología Molecular 'Prof. Dr. Andrés E. Carrasco', C1121ABG Buenos Aires, Argentina
| | | | - Lucía F Franchini
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), C1428ADN Buenos Aires, Argentina
| | - Silvia L López
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Biología Celular y Neurociencias 'Prof. E. De Robertis' (IBCN), Facultad de Medicina. Laboratorio de Embriología Molecular 'Prof. Dr. Andrés E. Carrasco', C1121ABG Buenos Aires, Argentina
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Shi Y, Li J, Chen C, Xia Y, Li Y, Zhang P, Xu Y, Li T, Zhou W, Song W. Ketamine Modulates Zic5 Expression via the Notch Signaling Pathway in Neural Crest Induction. Front Mol Neurosci 2018; 11:9. [PMID: 29472839 PMCID: PMC5810301 DOI: 10.3389/fnmol.2018.00009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 01/08/2018] [Indexed: 12/23/2022] Open
Abstract
Ketamine is a potent dissociative anesthetic and the most commonly used illicit drug. Many addicts are women at childbearing age. Although ketamine has been extensively studied as a clinical anesthetic, its effects on embryonic development are poorly understood. Here, we applied the Xenopus model to study the effects of ketamine on development. We found that exposure to ketamine from pre-gastrulation (stage 7) to early neural plate (stage 13.5) resulted in disruption of neural crest (NC) derivatives. Ketamine exposure did not affect mesoderm development as indicated by the normal expression of Chordin, Xbra, Wnt8, and Fgf8. However, ketamine treatment significantly inhibited Zic5 and Slug expression at early neural plate stage. Overexpression of Zic5 rescued ketamine-induced Slug inhibition, suggesting the blockage of NC induction was mediated by Zic5. Furthermore, we found Notch signaling was altered by ketamine. Ketamine inhibited the expression of Notch targeted genes including Hes5.2a, Hes5.2b, and ESR1 and ketamine-treated embryos exhibited Notch-deficient somite phenotypes. A 15 bp core binding element upstream of Zic5 was induced by Notch signaling and caused transcriptional activation. These results demonstrated that Zic5 works as a downstream target gene of Notch signaling in Xenopus NC induction. Our study provides a novel teratogenic mechanism whereby ketamine disrupts NC induction via targeting a Notch-Zic5 signaling pathway.
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Affiliation(s)
- Yu Shi
- Department of Clinical Laboratory, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Jiejing Li
- Department of Clinical Laboratory, The Affiliated Hospital of KMUST, Medical School, Kunming University of Science and Technology, Kunming, China
| | - Chunjiang Chen
- Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Yongwu Xia
- Department of Clinical Laboratory, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Yanxi Li
- Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Pan Zhang
- Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Department of Anesthesiology, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Ying Xu
- Department of Anesthesiology, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Tingyu Li
- Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Weihui Zhou
- Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Weihong Song
- Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, Vancouver, BC, Canada
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12
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Shao M, Wang M, Liu YY, Ge YW, Zhang YJ, Shi DL. Vegetally localised Vrtn functions as a novel repressor to modulate bmp2b transcription during dorsoventral patterning in zebrafish. Development 2017; 144:3361-3374. [PMID: 28928283 DOI: 10.1242/dev.152553] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 08/15/2017] [Indexed: 02/03/2023]
Abstract
The vegetal pole cytoplasm represents a crucial source of maternal dorsal determinants for patterning the dorsoventral axis of the early embryo. Removal of the vegetal yolk in the zebrafish fertilised egg before the completion of the first cleavage results in embryonic ventralisation, but removal of this part at the two-cell stage leads to embryonic dorsalisation. How this is achieved remains unknown. Here, we report a novel mode of maternal regulation of BMP signalling during dorsoventral patterning in zebrafish. We identify Vrtn as a novel vegetally localised maternal factor with dorsalising activity and rapid transport towards the animal pole region after fertilisation. Co-injection of vrtn mRNA with vegetal RNAs from different cleavage stages suggests the presence of putative vegetally localised Vrtn antagonists with slower animal pole transport. Thus, vegetal ablation at the two-cell stage could remove most of the Vrtn antagonists, and allows Vrtn to produce the dorsalising effect. Mechanistically, Vrtn binds a bmp2b regulatory sequence and acts as a repressor to inhibit its zygotic transcription. Analysis of maternal-zygotic vrtn mutants further shows that Vrtn is required to constrain excessive bmp2b expression in the margin. Our work unveils a novel maternal mechanism regulating zygotic BMP gradient in dorsoventral patterning.
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Affiliation(s)
- Ming Shao
- School of Life Science, Shandong University, 27 Shanda Nan road, Jinan 250100, China
| | - Min Wang
- School of Life Science, Shandong University, 27 Shanda Nan road, Jinan 250100, China
| | - Yuan-Yuan Liu
- School of Life Science, Shandong University, 27 Shanda Nan road, Jinan 250100, China
| | - Yi-Wen Ge
- School of Life Science, Shandong University, 27 Shanda Nan road, Jinan 250100, China
| | - Yan-Jun Zhang
- School of Life Science, Shandong University, 27 Shanda Nan road, Jinan 250100, China
| | - De-Li Shi
- School of Life Science, Shandong University, 27 Shanda Nan road, Jinan 250100, China .,Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR7622, IBPS-Developmental Biology Laboratory, 75005 Paris, France
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Yano Y, Iimura N, Kojima N, Uchiyama H. Non-neural and cardiac differentiating properties of Tbx6-expressing mouse embryonic stem cells. Regen Ther 2016; 3:1-6. [PMID: 31245465 PMCID: PMC6581818 DOI: 10.1016/j.reth.2016.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 01/10/2016] [Accepted: 02/08/2016] [Indexed: 11/30/2022] Open
Abstract
T-box transcription factors play important roles in vertebrate mesoderm formation. Eomesodermin is involved in the initial step of the prospective mesodermal cells recruited near the primitive streak. Then T or Brachyury gene is responsible for general and axial mesodermal development. Tbx6, on the other hand, promotes paraxial mesodermal development while suppressing neural differentiation. Here, we studied differentiative properties of mouse ES cells (mESCs) with its Tbx6 expression regulated under the Tet-off system. mESCs were treated with noggin to promote neural differentiation. When Tbx6 was simultaneously turned on, later neural differentiation of these cells hardly occurred. Next, mESCs were subjected to formation of the embryoid bodies (EBs). When Tbx6 was turned on during EB formation, the rate of later cardiac troponin T (cTnT)-positive cells increased. If the cells were further treated with a wnt inhibitor KY02111 after EB formation, a synergistic increase of cTnT-positive cells occurred. Tbx6 expression in mESCs influenced the constituent ratio of the cardiac myosin light chain types, such that atrial species markedly increased over ventricular ones. These results are coincident with the function of Tbx6 in normal development, in that Tbx6 strongly suppressed neural differentiation while promoting cardiac development in a cooperative manner with wnt inhibition. Tbx6 expression in mouse ES cells (mESCs) inhibited neural differentiation. Tbx6 expression in mESCs increased cardiac muscle synergistically with wnt inhibitor. Tbx6 expression increased atrial myosin light chains over ventricular chains.
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Affiliation(s)
- Yoshiteru Yano
- Graduate School of Nanobiosciences, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027, Japan
| | - Naoya Iimura
- Graduate School of Nanobiosciences, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027, Japan
| | - Nobuhiko Kojima
- Graduate School of Nanobiosciences, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027, Japan
| | - Hideho Uchiyama
- Graduate School of Nanobiosciences, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027, Japan
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14
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Carron C, Shi DL. Specification of anteroposterior axis by combinatorial signaling during Xenopus development. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2015; 5:150-68. [PMID: 26544673 DOI: 10.1002/wdev.217] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Revised: 09/01/2015] [Accepted: 09/12/2015] [Indexed: 01/08/2023]
Abstract
The specification of anteroposterior (AP) axis is a fundamental and complex patterning process that sets up the embryonic polarity and shapes a multicellular organism. This process involves the integration of distinct signaling pathways to coordinate temporal-spatial gene expression and morphogenetic movements. In the frog Xenopus, extensive embryological and molecular studies have provided major advance in understanding the mechanism implicated in AP patterning. Following fertilization, cortical rotation leads to the transport of maternal determinants to the dorsal region and creates the primary dorsoventral (DV) asymmetry. The activation of maternal Wnt/ß-catenin signaling and a high Nodal signal induces the formation of the Nieuwkoop center in the dorsal-vegetal cells, which then triggers the formation of the Spemann organizer in the overlying dorsal marginal zone. It is now well established that the Spemann organizer plays a central role in building the vertebrate body axes because it provides patterning information for both DV and AP polarities. The antagonistic interactions between signals secreted in the Spemann organizer and the opposite ventral region pattern the mesoderm along the DV axis, and this DV information is translated into AP positional values during gastrulation. The formation of anterior neural tissue requires simultaneous inhibition of zygotic Wnt and bone morphogenetic protein (BMP) signals, while an endogenous gradient of Wnt, fibroblast growth factors (FGFs), retinoic acid (RA) signaling, and collinearly expressed Hox genes patterns the trunk and posterior regions. Collectively, DV asymmetry is mostly coupled to AP polarity, and cell-cell interactions mediated essentially by the same regulatory networks operate in DV and AP patterning. For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Clémence Carron
- Laboratory of Developmental Biology, Sorbonne Universités, Institut de Biologie Paris-Seine (IBPS), Paris, France
| | - De-Li Shi
- Laboratory of Developmental Biology, Sorbonne Universités, Institut de Biologie Paris-Seine (IBPS), Paris, France.,School of Life Sciences, Shandong University, Jinan, China
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15
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Li HY, Grifone R, Saquet A, Carron C, Shi DL. The Xenopus homologue of Down syndrome critical region protein 6 drives dorsoanterior gene expression and embryonic axis formation by antagonising polycomb group proteins. Development 2013; 140:4903-13. [DOI: 10.1242/dev.098319] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Mesoderm and embryonic axis formation in vertebrates is mediated by maternal and zygotic factors that activate the expression of target genes. Transcriptional derepression plays an important role in the regulation of expression in different contexts; however, its involvement and possible mechanism in mesoderm and embryonic axis formation are largely unknown. Here we demonstrate that XDSCR6, a Xenopus homologue of human Down syndrome critical region protein 6 (DSCR6, or RIPPLY3), regulates mesoderm and embryonic axis formation through derepression of polycomb group (PcG) proteins. Xdscr6 maternal mRNA is enriched in the endoderm of the early gastrula and potently triggers the formation of dorsal mesoderm and neural tissues in ectoderm explants; it also dorsalises ventral mesoderm during gastrulation and induces a secondary embryonic axis. A WRPW motif, which is present in all DSCR6 homologues, is necessary and sufficient for the dorsal mesoderm- and axis-inducing activity. Knockdown of Xdscr6 inhibits dorsal mesoderm gene expression and results in head deficiency. We further show that XDSCR6 physically interacts with PcG proteins through the WRPW motif, preventing the formation of PcG bodies and antagonising their repressor activity in embryonic axis formation. By chromatin immunoprecipitation, we demonstrate that XDSCR6 releases PcG proteins from chromatin and allows dorsal mesoderm gene transcription. Our studies suggest that XDSCR6 might function to sequester PcG proteins and identify a novel derepression mechanism implicated in embryonic induction and axis formation.
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Affiliation(s)
- Hong-Yan Li
- Laboratory of Developmental Biology, CNRS UMR 7622, University Pierre et Marie Curie, 9 quai Saint-Bernard, 75005 Paris, France
- Department of Marine Biology, Ocean University of China, Qingdao 266003, China
| | - Raphaëlle Grifone
- Laboratory of Developmental Biology, CNRS UMR 7622, University Pierre et Marie Curie, 9 quai Saint-Bernard, 75005 Paris, France
| | - Audrey Saquet
- Laboratory of Developmental Biology, CNRS UMR 7622, University Pierre et Marie Curie, 9 quai Saint-Bernard, 75005 Paris, France
| | - Clémence Carron
- Laboratory of Developmental Biology, CNRS UMR 7622, University Pierre et Marie Curie, 9 quai Saint-Bernard, 75005 Paris, France
| | - De-Li Shi
- Laboratory of Developmental Biology, CNRS UMR 7622, University Pierre et Marie Curie, 9 quai Saint-Bernard, 75005 Paris, France
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16
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Cao JM, Li SQ, Zhang HW, Shi DL. High mobility group B proteins regulate mesoderm formation and dorsoventral patterning during zebrafish and Xenopus early development. Mech Dev 2012; 129:263-74. [DOI: 10.1016/j.mod.2012.07.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 06/29/2012] [Accepted: 07/02/2012] [Indexed: 10/28/2022]
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17
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Maguire RJ, Isaacs HV, Pownall ME. Early transcriptional targets of MyoD link myogenesis and somitogenesis. Dev Biol 2012; 371:256-68. [PMID: 22954963 DOI: 10.1016/j.ydbio.2012.08.027] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 07/10/2012] [Accepted: 08/22/2012] [Indexed: 12/20/2022]
Abstract
In order to identify early transcriptional targets of MyoD prior to skeletal muscle differentiation, we have undertaken a transcriptomic analysis on gastrula stage Xenopus embryos in which MyoD has been knocked-down. Our validated list of genes transcriptionally regulated by MyoD includes Esr1 and Esr2, which are known targets of Notch signalling, and Tbx6, mesogenin, and FoxC1; these genes are all are known to be essential for normal somitogenesis but are expressed surprisingly early in the mesoderm. In addition we found that MyoD is required for the expression of myf5 in the early mesoderm, in contrast to the reverse relationship of these two regulators in amniote somites. These data highlight a role for MyoD in the early mesoderm in regulating a set of genes that are essential for both myogenesis and somitogenesis.
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Affiliation(s)
- Richard J Maguire
- Biology Department, University of York, Heslington, York, North Yorkshire YO10 5YW, UK
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18
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Shi J, Severson C, Yang J, Wedlich D, Klymkowsky MW. Snail2 controls mesodermal BMP/Wnt induction of neural crest. Development 2011; 138:3135-45. [PMID: 21715424 DOI: 10.1242/dev.064394] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The neural crest is an induced tissue that is unique to vertebrates. In the clawed frog Xenopus laevis, neural crest induction depends on signals secreted from the prospective dorsolateral mesodermal zone during gastrulation. The transcription factors Snail2 (Slug), Snail1 and Twist1 are expressed in this region. It is known that Snail2 and Twist1 are required for both mesoderm formation and neural crest induction. Using targeted blastomere injection, morpholino-based loss of function and explant studies, we show that: (1) Snail1 is also required for mesoderm and neural crest formation; (2) loss of snail1, snail2 or twist1 function in the C2/C3 lineage of 32-cell embryos blocks mesoderm formation, but neural crest is lost only in the case of snail2 loss of function; (3) snail2 mutant loss of neural crest involves mesoderm-derived secreted factors and can be rescued synergistically by bmp4 and wnt8 RNAs; and (4) loss of snail2 activity leads to changes in the RNA levels of a number of BMP and Wnt agonists and antagonists. Taken together, these results identify Snail2 as a key regulator of the signals involved in mesodermal induction of neural crest.
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Affiliation(s)
- Jianli Shi
- Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO 80309-0347, USA
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19
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Janssen R, Budd GE, Prpic NM, Damen WG. Expression of myriapod pair rule gene orthologs. EvoDevo 2011; 2:5. [PMID: 21352542 PMCID: PMC3058060 DOI: 10.1186/2041-9139-2-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Accepted: 02/25/2011] [Indexed: 11/18/2022] Open
Abstract
Background Segmentation is a hallmark of the arthropods; most knowledge about the molecular basis of arthropod segmentation comes from work on the fly Drosophila melanogaster. In this species a hierarchic cascade of segmentation genes subdivides the blastoderm stepwise into single segment wide regions. However, segmentation in the fly is a derived feature since all segments form virtually simultaneously. Conversely, in the vast majority of arthropods the posterior segments form one at a time from a posterior pre-segmental zone. The pair rule genes (PRGs) comprise an important level of the Drosophila segmentation gene cascade and are indeed the first genes that are expressed in typical transverse stripes in the early embryo. Information on expression and function of PRGs outside the insects, however, is scarce. Results Here we present the expression of the pair rule gene orthologs in the pill millipede Glomeris marginata (Myriapoda: Diplopoda). We find evidence that these genes are involved in segmentation and that components of the hierarchic interaction of the gene network as found in insects may be conserved. We further provide evidence that segments are formed in a single-segment periodicity rather than in pairs of two like in another myriapod, the centipede Strigamia maritima. Finally we show that decoupling of dorsal and ventral segmentation in Glomeris appears already at the level of the PRGs. Conclusions Although the pair rule gene network is partially conserved among insects and myriapods, some aspects of PRG interaction are, as suggested by expression pattern analysis, convergent, even within the Myriapoda. Conserved expression patterns of PRGs in insects and myriapods, however, may represent ancestral features involved in segmenting the arthropod ancestor.
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Affiliation(s)
- Ralf Janssen
- Uppsala University, Department of Earth Sciences, Palaeobiology, Villavägen 16, SE-752 36 Uppsala, Sweden.
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20
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Janssen R, Le Gouar M, Pechmann M, Poulin F, Bolognesi R, Schwager EE, Hopfen C, Colbourne JK, Budd GE, Brown SJ, Prpic NM, Kosiol C, Vervoort M, Damen WGM, Balavoine G, McGregor AP. Conservation, loss, and redeployment of Wnt ligands in protostomes: implications for understanding the evolution of segment formation. BMC Evol Biol 2010; 10:374. [PMID: 21122121 PMCID: PMC3003278 DOI: 10.1186/1471-2148-10-374] [Citation(s) in RCA: 126] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Accepted: 12/01/2010] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The Wnt genes encode secreted glycoprotein ligands that regulate a wide range of developmental processes, including axis elongation and segmentation. There are thirteen subfamilies of Wnt genes in metazoans and this gene diversity appeared early in animal evolution. The loss of Wnt subfamilies appears to be common in insects, but little is known about the Wnt repertoire in other arthropods, and moreover the expression and function of these genes have only been investigated in a few protostomes outside the relatively Wnt-poor model species Drosophila melanogaster and Caenorhabditis elegans. To investigate the evolution of this important gene family more broadly in protostomes, we surveyed the Wnt gene diversity in the crustacean Daphnia pulex, the chelicerates Ixodes scapularis and Achaearanea tepidariorum, the myriapod Glomeris marginata and the annelid Platynereis dumerilii. We also characterised Wnt gene expression in the latter three species, and further investigated expression of these genes in the beetle Tribolium castaneum. RESULTS We found that Daphnia and Platynereis both contain twelve Wnt subfamilies demonstrating that the common ancestors of arthropods, ecdysozoans and protostomes possessed all members of all Wnt subfamilies except Wnt3. Furthermore, although there is striking loss of Wnt genes in insects, other arthropods have maintained greater Wnt gene diversity. The expression of many Wnt genes overlap in segmentally reiterated patterns and in the segment addition zone, and while these patterns can be relatively conserved among arthropods and the annelid, there have also been changes in the expression of some Wnt genes in the course of protostome evolution. Nevertheless, our results strongly support the parasegment as the primary segmental unit in arthropods, and suggest further similarities between segmental and parasegmental regulation by Wnt genes in annelids and arthropods respectively. CONCLUSIONS Despite frequent losses of Wnt gene subfamilies in lineages such as insects, nematodes and leeches, most protostomes have probably maintained much of their ancestral repertoire of twelve Wnt genes. The maintenance of a large set of these ligands could be in part due to their combinatorial activity in various tissues rather than functional redundancy. The activity of such Wnt 'landscapes' as opposed to the function of individual ligands could explain the patterns of conservation and redeployment of these genes in important developmental processes across metazoans. This requires further analysis of the expression and function of these genes in a wider range of taxa.
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Affiliation(s)
- Ralf Janssen
- Department of Earth Sciences, Palaeobiology, Villavägen 16, SE-75236 Uppsala, Sweden
| | - Martine Le Gouar
- Centre de Génétique Moléculaire du CNRS, FRE 3144, avenue de la Terrasse 91198 Gif-sur-Yvette, France
| | - Matthias Pechmann
- Georg-August-Universität Göttingen, Johann-Friedrich-Blumenbach-Institut für Zoologie und Anthropologie, Abteilung Entwicklungsbiologie, GZMB, Ernst-Caspari-Haus, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
| | - Francis Poulin
- Department of Integrative Biology, University of California, Berkeley, CA 94720, USA
- Genzyme Corporation, One The Mountain Road, Framingham, MA 01701, USA
| | - Renata Bolognesi
- Division of Biology, Kansas State University, Manhattan, KS 66506, USA
- Monsanto Company, St. Louis, MO, 63107, USA
| | - Evelyn E Schwager
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave, Cambridge MA 02138, USA
| | - Corinna Hopfen
- Institut für Populationsgenetik, Veterinärmedizinische Universität Wien, Veterinärplatz 1, A-1210, Vienna, Austria
| | - John K Colbourne
- The Center for Genomics and Bioinformatics, Indiana University, Bloomington, IN 47405, USA
| | - Graham E Budd
- Department of Earth Sciences, Palaeobiology, Villavägen 16, SE-75236 Uppsala, Sweden
| | - Susan J Brown
- Division of Biology, Kansas State University, Manhattan, KS 66506, USA
| | - Nikola-Michael Prpic
- Georg-August-Universität Göttingen, Johann-Friedrich-Blumenbach-Institut für Zoologie und Anthropologie, Abteilung Entwicklungsbiologie, GZMB, Ernst-Caspari-Haus, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
| | - Carolin Kosiol
- Institut für Populationsgenetik, Veterinärmedizinische Universität Wien, Veterinärplatz 1, A-1210, Vienna, Austria
| | - Michel Vervoort
- Centre de Génétique Moléculaire du CNRS, FRE 3144, avenue de la Terrasse 91198 Gif-sur-Yvette, France
- Institut Jacques Monod, CNRS/Université Paris-Diderot, 15 rue Hélène Brion, 75205 Paris Cedex 13, France
| | - Wim GM Damen
- Friedrich-Schiller-University Jena, Department of Genetics, Philosophenweg 12, 07743 Jena, Germany
| | - Guillaume Balavoine
- Centre de Génétique Moléculaire du CNRS, FRE 3144, avenue de la Terrasse 91198 Gif-sur-Yvette, France
- Institut Jacques Monod, CNRS/Université Paris-Diderot, 15 rue Hélène Brion, 75205 Paris Cedex 13, France
| | - Alistair P McGregor
- Institut für Populationsgenetik, Veterinärmedizinische Universität Wien, Veterinärplatz 1, A-1210, Vienna, Austria
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21
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Yao S, Qian M, Deng S, Xie L, Yang H, Xiao C, Zhang T, Xu H, Zhao X, Wei YQ, Mo X. Kzp controls canonical Wnt8 signaling to modulate dorsoventral patterning during zebrafish gastrulation. J Biol Chem 2010; 285:42086-96. [PMID: 20978132 DOI: 10.1074/jbc.m110.161554] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
During vertebrate embryonic development, the body axis formation requires the action of Wnt signals and their antagonists. Zygotic canonical wnt8 expression appears exclusively at the ventrolateral margin and mediates Wnt/β-catenin activities to promote posterior and ventral cell fate. However, the mechanisms involved in the initiation of zygotic wnt8 signals are poorly understood. Here, we identify a novel, maternally derived transcription factor, Kzp (Kaiso zinc finger-containing protein), as an important determinant for the initiation of zygotic Wnt signals in zebrafish. Kzp is a DNA-binding transcription factor that recognizes specific consensus DNA sequences, 5'-(t/a/g)t(a/t/g)nctgcca-3', through zinc fingers and controls the initiation of zygotic wnt8 expression by directly binding to the wnt8 promoter during zebrafish embryonic development. Depletion of Kzp strongly dorsalized embryos, which was characterized by the expansion of dorsal gene expression. Overexpression of Kzp caused posteriorization. These phenotypes were highly similar to ones induced by wnt8 depletion or overexpression and were rescued by alteration of wnt8 activity. Thus, our results provide the first insight into the mechanism involved in the initiation of zygotic canonical Wnt signals by a maternally derived transcription factor.
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Affiliation(s)
- Shaohua Yao
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, China
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22
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Paraxial T-box genes, Tbx6 and Tbx1, are required for cranial chondrogenesis and myogenesis. Dev Biol 2010; 346:170-80. [DOI: 10.1016/j.ydbio.2010.07.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 06/12/2010] [Accepted: 07/06/2010] [Indexed: 12/18/2022]
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Callery EM, Thomsen GH, Smith JC. A divergent Tbx6-related gene and Tbx6 are both required for neural crest and intermediate mesoderm development in Xenopus. Dev Biol 2010; 340:75-87. [PMID: 20083100 PMCID: PMC2877776 DOI: 10.1016/j.ydbio.2010.01.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2008] [Revised: 12/23/2009] [Accepted: 01/08/2010] [Indexed: 10/31/2022]
Abstract
T-box family transcription factors play many roles in Metazoan development. Here we characterise Tbx6r, a unique Tbx6 paralogue isolated from the amphibian Xenopus. The evolution and developmental integration of this divergent T-box gene within the vertebrates reveals an unexpected level of plasticity within this conserved family of developmental regulators. We show that despite their co-expression, Tbx6 and Tbx6r have dissimilar transcriptional responses to ligand treatment, and their ability to activate ligand expression is also very different. The two paralogues have distinct inductive properties: Tbx6 induces mesoderm whereas Tbx6r induces anterior neural markers. We use hybrid proteins in an effort to understand this difference, and implicate the C-terminal regions of the proteins in their inductive specificities. Through loss-of-function analyses using antisense morpholino oligonucleotides we show that both Tbx6 paralogues perform essential functions in the development of the paraxial and intermediate mesoderm and the neural crest in Xenopus. We demonstrate that Tbx6 and Tbx6r both induce FGF8 expression as well as that of pre-placodal markers, and that Tbx6 can also induce neural crest markers via a ligand-dependent mechanism involving FGF8 and Wnt8. Our data thus identify an important new function for this key developmental regulator.
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Affiliation(s)
- Elizabeth M Callery
- The Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Zoology, The Henry Wellcome Building of Cancer and Developmental Biology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK.
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24
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Li HY, Bourdelas A, Carron C, Shi DL. The RNA-binding protein Seb4/RBM24 is a direct target of MyoD and is required for myogenesis during Xenopus early development. Mech Dev 2010; 127:281-91. [PMID: 20338237 DOI: 10.1016/j.mod.2010.03.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Revised: 03/17/2010] [Accepted: 03/19/2010] [Indexed: 10/19/2022]
Abstract
RNA-binding proteins play an important role to post-transcriptionally regulate gene expression. During early development they exhibit temporally and spatially regulated expression pattern. The expression of Xenopus laevis Seb4 gene, also known as RBM24 in other vertebrates, is restricted to the lateral and ventral mesoderm during gastrulation and then localized to the somitic mesoderm, in a similar pattern as XMyoD gene. Using a hormone-inducible form of MyoD to identify potential direct MyoD target genes, we find that Seb4 expression is directly regulated by MyoD at the gastrula stage. We further show that a 0.65kb X. tropicalis RBM24 regulatory region contains multiple E boxes (CANNTG), which are potential binding sites for MyoD and other bHLH proteins. By injecting a RBM24 reporter construct into the animal pole of X. laevis embryos, we find that this reporter gene is indeed specifically activated by MyoD and repressed by a dominant negative MyoD mutant. Knockdown of Seb4 produces similar effects as those obtained by the dominant negative MyoD mutant, indicating that it is required for the expression of myogenic genes and myogenesis in the embryo. In cultured ectodermal explants, although overexpression of Seb4 has no obvious effect on myogenesis, knockdown of Seb4 inhibits the expression of myogenic genes and myogenesis induced by MyoD. These results reveal that Seb4 is a target of MyoD during myogenesis and is required for myogenic gene expression.
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Affiliation(s)
- Hong-Yan Li
- Groupe de Biologie Expérimentale, Laboratoire de Biologie du Développement, CNRS UMR 7622, Université Pierre et Marie Curie, 9 quai Saint-Bernard, 75005 Paris, France
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25
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Tazumi S, Yabe S, Yokoyama J, Aihara Y, Uchiyama H. PMesogenin1 and 2 function directly downstream of Xtbx6 in Xenopus somitogenesis and myogenesis. Dev Dyn 2009; 237:3749-61. [PMID: 19035338 DOI: 10.1002/dvdy.21791] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
T-box transcription factor tbx6 and basic-helix-loop-helix transcription factor pMesogenin1 are reported to be involved in paraxial mesodermal differentiation. To clarify the relationship between these genes in Xenopus laevis, we isolated pMesogenin2, which showed high homology with pMesogenin1. Both pMesogenin1 and 2 appeared to be transcriptional activators and were induced by a hormone-inducible version of Xtbx6 without secondary protein synthesis in animal cap assays. The pMesogenin2 promoter contained three potential T-box binding sites with which Xtbx6 protein was shown to interact, and a reporter gene construct containing these sites was activated by Xtbx6. Xtbx6 knockdown reduced pMesogenin1 and 2 expressions, but not vice versa. Xtbx6 and pMesogenin1 and 2 knockdowns caused similar phenotypic abnormalities including somite malformation and ventral body wall muscle hypoplasia, suggesting that Xtbx6 is a direct regulator of pMesogenin1 and 2, which are both involved in somitogenesis and myogenesis including that of body wall muscle in Xenopus laevis.
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Affiliation(s)
- Shunsuke Tazumi
- International Graduate School of Arts and Sciences, Yokohama City University, Yokohama, Japan
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26
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Bolognesi R, Farzana L, Fischer TD, Brown SJ. Multiple Wnt genes are required for segmentation in the short-germ embryo of Tribolium castaneum. Curr Biol 2008; 18:1624-9. [PMID: 18926702 PMCID: PMC2603327 DOI: 10.1016/j.cub.2008.09.057] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Revised: 09/23/2008] [Accepted: 09/24/2008] [Indexed: 02/06/2023]
Abstract
wingless (wg)/Wnt family are essential to development in virtually all metazoans. In short-germ insects, including the red flour beetle (Tribolium castaneum), the segment-polarity function of wg is conserved [1]. Wnt signaling is also implicated in posterior patterning and germband elongation [2-4], but despite its expression in the posterior growth zone, Wnt1/wg alone is not responsible for these functions [1-3]. Tribolium contains additional Wnt family genes that are also expressed in the growth zone [5]. After depleting Tc-WntD/8 we found a small percentage of embryos lacking abdominal segments. Additional removal of Tc-Wnt1 significantly enhanced the penetrance of this phenotype. Seeking alternative methods to deplete Wnt signal, we performed RNAi with other components of the Wnt pathway including wntless (wls), porcupine (porc), and pangolin (pan). Tc-wls RNAi caused segmentation defects similar to Tc-Wnt1 RNAi, but not Tc-WntD/8 RNAi, indicating that Tc-WntD/8 function is Tc-wls independent. Depletion of Tc-porc and Tc-pan produced embryos resembling double Tc-Wnt1,Tc-WntD/8 RNAi embryos, suggesting that Tc-porc is essential for the function of both ligands, which signal through the canonical pathway. This is the first evidence of functional redundancy between Wnt ligands in posterior patterning in short-germ insects. This Wnt function appears to be conserved in other arthropods [6] and vertebrates [7-9].
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Affiliation(s)
- Renata Bolognesi
- Division of Biology, Ackert Hall, Kansas State University, Manhattan, Kansas 66502 USA, Tel 785 532-3935 Fax 785 532 6653
| | - Laila Farzana
- Division of Biology, Ackert Hall, Kansas State University, Manhattan, Kansas 66502 USA, Tel 785 532-3935 Fax 785 532 6653
| | - Tamara D. Fischer
- Division of Biology, Ackert Hall, Kansas State University, Manhattan, Kansas 66502 USA, Tel 785 532-3935 Fax 785 532 6653
| | - Susan J. Brown
- Division of Biology, Ackert Hall, Kansas State University, Manhattan, Kansas 66502 USA, Tel 785 532-3935 Fax 785 532 6653
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McGregor AP, Pechmann M, Schwager EE, Feitosa NM, Kruck S, Aranda M, Damen WG. Wnt8 Is Required for Growth-Zone Establishment and Development of Opisthosomal Segments in a Spider. Curr Biol 2008; 18:1619-23. [DOI: 10.1016/j.cub.2008.08.045] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Revised: 06/13/2008] [Accepted: 08/11/2008] [Indexed: 12/11/2022]
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Lou X, Fang P, Li S, Hu RY, Kuerner KM, Steinbeisser H, Ding X. Xenopus Tbx6 mediates posterior patterning via activation of Wnt and FGF signalling. Cell Res 2008; 16:771-9. [PMID: 16953215 DOI: 10.1038/sj.cr.7310093] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
In vertebrates, the patterning of anterior-posterior (AP) axis is a fundamental process during embryogenesis. Wnt and FGF signalling pathways play important roles in regulating the patterning of embryo AP axis. Mouse Tbx6 encodes a transcription factor that has been demonstrated to be involved in the specification of the posterior tissue in mouse embryonic body. Here, we prove that morpholino-induced knockdown of XTbx6 impairs posterior development, indicating the requirement of XTbx6 in this process. Meanwhile, gain of XTbx6 function is sufficient to induce ectopic posterior structures in Xenopus embryos. Furthermore, XTbx6 activates the expression of Xwnt8 and FGF8, which are two mediators of posterior development, suggesting a mechanism by which XTbx6 modulates posterior patterning via Wnt and FGF signalling pathway activation.
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Affiliation(s)
- Xin Lou
- Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai, China
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Hitachi K, Kondow A, Danno H, Inui M, Uchiyama H, Asashima M. Tbx6, Thylacine1, and E47 synergistically activate bowline expression in Xenopus somitogenesis. Dev Biol 2008; 313:816-28. [DOI: 10.1016/j.ydbio.2007.10.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2007] [Revised: 09/23/2007] [Accepted: 10/16/2007] [Indexed: 12/20/2022]
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Multiple upstream modules regulate zebrafish myf5 expression. BMC DEVELOPMENTAL BIOLOGY 2007; 7:1. [PMID: 17199897 PMCID: PMC1769357 DOI: 10.1186/1471-213x-7-1] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Accepted: 01/03/2007] [Indexed: 11/27/2022]
Abstract
Background Myf5 is one member of the basic helix-loop-helix family of transcription factors, and it functions as a myogenic factor that is important for the specification and differentiation of muscle cells. The expression of myf5 is somite- and stage-dependent during embryogenesis through a delicate regulation. However, this complex regulatory mechanism of myf5 is not clearly understood. Results We isolated a 156-kb bacterial artificial chromosome clone that includes an upstream 80-kb region and a downstream 70-kb region of zebrafish myf5 and generated a transgenic line carrying this 156-kb segment fused to a green fluorescent protein (GFP) reporter gene. We find strong GFP expression in the most rostral somite and in the presomitic mesoderm during segmentation stages, similar to endogenous myf5 expression. Later, the GFP signals persist in caudal somites near the tail bud but are down-regulated in the older, rostral somites. During the pharyngula period, we detect GFP signals in pectoral fin buds, dorsal rostral myotomes, hypaxial myotomes, and inferior oblique and superior oblique muscles, a pattern that also corresponds well with endogenous myf5 transcripts. To characterize the specific upstream cis-elements that regulate this complex and dynamic expression pattern, we also generated several transgenic lines that harbor various lengths within the upstream 80-kb segment. We find that (1) the -80 kb/-9977 segment contains a fin and cranial muscle element and a notochord repressor; (2) the -9977/-6213 segment contains a strong repressive element that does not include the notochord-specific repressor; (3) the -6212/-2938 segment contains tissue-specific elements for bone and spinal cord; (4) the -2937/-291 segment contains an eye enhancer, and the -2937/-2457 segment is required for notochord and myocyte expression; and (5) the -290/-1 segment is responsible for basal transcription in somites and the presomitic mesoderm. Conclusion We suggest that the cell lineage-specific expression of myf5 is delicately orchestrated by multiple modules within the distal upstream region. This study provides an insight to understand the molecular control of myf5 and myogenesis in the zebrafish.
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Buckingham M. Myogenic progenitor cells and skeletal myogenesis in vertebrates. Curr Opin Genet Dev 2006; 16:525-32. [PMID: 16930987 DOI: 10.1016/j.gde.2006.08.008] [Citation(s) in RCA: 324] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2006] [Accepted: 08/03/2006] [Indexed: 01/21/2023]
Abstract
Continuing research on the onset of skeletal myogenesis in the somite is providing new insights into the behaviour of early myogenic progenitor cells and how signalling molecules affect cell fate decisions, in addition to subsequent muscle growth. Genetic manipulations have revealed new regulatory aspects, including the role of Six transcription factors and the CXCR4 cytokine receptor during embryonic myogenesis. An important recent development is the identification of a novel population of somite-derived cells that make a major contribution to muscle growth. These cells, which are characterised by the expression of Pax3 and Pax7, also give rise to the satellite cells of postnatal muscle. The relationship between Pax and Myogenic regulatory factors has been explored. Furthermore, Pax7 is now shown to be required for the maintenance of satellite cells. New approaches that permit the grafting of purified satellite cells demonstrate their capacity for efficient muscle repair and for self-renewal. Regeneration in amphibians is now also shown to involve Pax-positive progenitor cells.
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Affiliation(s)
- Margaret Buckingham
- Department of Developmental Biology, CNRS URA2578, Pasteur Institute, 25 Rue du Docteur Roux, 75015 Paris Cedex, France.
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