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Warns J, Kim YI, O'Rourke R, Sagerström CG. scMultiome analysis identifies a single caudal hindbrain compartment in the developing zebrafish nervous system. Neural Dev 2024; 19:12. [PMID: 38970093 PMCID: PMC11225431 DOI: 10.1186/s13064-024-00189-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Accepted: 06/27/2024] [Indexed: 07/07/2024] Open
Abstract
BACKGROUND A key step in nervous system development involves the coordinated control of neural progenitor specification and positioning. A long-standing model for the vertebrate CNS postulates that transient anatomical compartments - known as neuromeres - function to position neural progenitors along the embryonic anteroposterior neuraxis. Such neuromeres are apparent in the embryonic hindbrain - that contains six rhombomeres with morphologically apparent boundaries - but other neuromeres lack clear morphological boundaries and have instead been defined by different criteria, such as differences in gene expression patterns and the outcomes of transplantation experiments. Accordingly, the caudal hindbrain (CHB) posterior to rhombomere (r) 6 has been variably proposed to contain from two to five 'pseudo-rhombomeres', but the lack of comprehensive molecular data has precluded a detailed definition of such structures. METHODS We used single-cell Multiome analysis, which allows simultaneous characterization of gene expression and chromatin state of individual cell nuclei, to identify and characterize CHB progenitors in the developing zebrafish CNS. RESULTS We identified CHB progenitors as a transcriptionally distinct population, that also possesses a unique profile of accessible transcription factor binding motifs, relative to both r6 and the spinal cord. This CHB population can be subdivided along its dorsoventral axis based on molecular characteristics, but we do not find any molecular evidence that it contains multiple pseudo-rhombomeres. We further observe that the CHB is closely related to r6 at the earliest embryonic stages, but becomes more divergent over time, and that it is defined by a unique gene regulatory network. CONCLUSIONS We conclude that the early CHB represents a single neuromere compartment that cannot be molecularly subdivided into pseudo-rhombomeres and that it may share an embryonic origin with r6.
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Affiliation(s)
- Jessica Warns
- Section of Developmental Biology, Department of Pediatrics, University of Colorado Medical School, 12801 E. 17th Avenue, Aurora, CO, 80045, USA
- Department of Science and Math, Northern State University, 1200 S. Jay St, Aberdeen, SD, 57401, USA
| | - Yong-Ii Kim
- Section of Developmental Biology, Department of Pediatrics, University of Colorado Medical School, 12801 E. 17th Avenue, Aurora, CO, 80045, USA
| | - Rebecca O'Rourke
- Section of Developmental Biology, Department of Pediatrics, University of Colorado Medical School, 12801 E. 17th Avenue, Aurora, CO, 80045, USA
| | - Charles G Sagerström
- Section of Developmental Biology, Department of Pediatrics, University of Colorado Medical School, 12801 E. 17th Avenue, Aurora, CO, 80045, USA.
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Lozovska A, Korovesi AG, Duarte P, Casaca A, Assunção T, Mallo M. The control of transitions along the main body axis. Curr Top Dev Biol 2023; 159:272-308. [PMID: 38729678 DOI: 10.1016/bs.ctdb.2023.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2024]
Abstract
Although vertebrates display a large variety of forms and sizes, the mechanisms controlling the layout of the basic body plan are substantially conserved throughout the clade. Following gastrulation, head, trunk, and tail are sequentially generated through the continuous addition of tissue at the caudal embryonic end. Development of each of these major embryonic regions is regulated by a distinct genetic network. The transitions from head-to-trunk and from trunk-to-tail development thus involve major changes in regulatory mechanisms, requiring proper coordination to guarantee smooth progression of embryonic development. In this review, we will discuss the key cellular and embryological events associated with those transitions giving particular attention to their regulation, aiming to provide a cohesive outlook of this important component of vertebrate development.
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Affiliation(s)
| | | | - Patricia Duarte
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, Oeiras, Portugal
| | - Ana Casaca
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, Oeiras, Portugal
| | - Tereza Assunção
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, Oeiras, Portugal
| | - Moises Mallo
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, Oeiras, Portugal.
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England SJ, Rusnock AK, Mujcic A, Kowalchuk A, de Jager S, Hilinski WC, Juárez-Morales JL, Smith ME, Grieb G, Banerjee S, Lewis KE. Molecular analyses of zebrafish V0v spinal interneurons and identification of transcriptional regulators downstream of Evx1 and Evx2 in these cells. Neural Dev 2023; 18:8. [PMID: 38017520 PMCID: PMC10683209 DOI: 10.1186/s13064-023-00176-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 10/12/2023] [Indexed: 11/30/2023] Open
Abstract
BACKGROUND V0v spinal interneurons are highly conserved, glutamatergic, commissural neurons that function in locomotor circuits. We have previously shown that Evx1 and Evx2 are required to specify the neurotransmitter phenotype of these cells. However, we still know very little about the gene regulatory networks that act downstream of these transcription factors in V0v cells. METHODS To identify candidate members of V0v gene regulatory networks, we FAC-sorted wild-type and evx1;evx2 double mutant zebrafish V0v spinal interneurons and expression-profiled them using microarrays and single cell RNA-seq. We also used in situ hybridization to compare expression of a subset of candidate genes in evx1;evx2 double mutants and wild-type siblings. RESULTS Our data reveal two molecularly distinct subtypes of zebrafish V0v spinal interneurons at 48 h and suggest that, by this stage of development, evx1;evx2 double mutant cells transfate into either inhibitory spinal interneurons, or motoneurons. Our results also identify 25 transcriptional regulator genes that require Evx1/2 for their expression in V0v interneurons, plus a further 11 transcriptional regulator genes that are repressed in V0v interneurons by Evx1/2. Two of the latter genes are hmx2 and hmx3a. Intriguingly, we show that Hmx2/3a, repress dI2 interneuron expression of skor1a and nefma, two genes that require Evx1/2 for their expression in V0v interneurons. This suggests that Evx1/2 might regulate skor1a and nefma expression in V0v interneurons by repressing Hmx2/3a expression. CONCLUSIONS This study identifies two molecularly distinct subsets of zebrafish V0v spinal interneurons, as well as multiple transcriptional regulators that are strong candidates for acting downstream of Evx1/2 to specify the essential functional characteristics of these cells. Our data further suggest that in the absence of both Evx1 and Evx2, V0v spinal interneurons initially change their neurotransmitter phenotypes from excitatory to inhibitory and then, later, start to express markers of distinct types of inhibitory spinal interneurons, or motoneurons. Taken together, our findings significantly increase our knowledge of V0v and spinal development and move us closer towards the essential goal of identifying the complete gene regulatory networks that specify this crucial cell type.
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Affiliation(s)
| | | | - Amra Mujcic
- Biology Department, Syracuse University, Syracuse, NY, USA
| | | | - Sarah de Jager
- Physiology, Development and Neuroscience Department, Cambridge University, Cambridge, UK
| | | | - José L Juárez-Morales
- Biology Department, Syracuse University, Syracuse, NY, USA
- Programa de IxM-CONAHCYT, Centro de Investigaciones Biológicas del Noroeste, S.C. (CIBNOR), La Paz, Baja California Sur, México
| | | | - Ginny Grieb
- Biology Department, Syracuse University, Syracuse, NY, USA
| | - Santanu Banerjee
- Biological Sciences Department, SUNY-Cortland, Cortland, NY, USA
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England SJ, Woodard AK, Mujcic A, Kowalchuk A, de Jager S, Hilinski WC, Juárez-Morales JL, Smith ME, Grieb G, Banerjee S, Lewis KE. Molecular Analyses of V0v Spinal Interneurons and Identification of Transcriptional Regulators Downstream of Evx1 and Evx2 in these Cells. RESEARCH SQUARE 2023:rs.3.rs-3290462. [PMID: 37693471 PMCID: PMC10491344 DOI: 10.21203/rs.3.rs-3290462/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Background V0v spinal interneurons are highly conserved, glutamatergic, commissural neurons that function in locomotor circuits. We have previously shown that Evx1 and Evx2 are required to specify the neurotransmitter phenotype of these cells. However, we still know very little about the gene regulatory networks that act downstream of these transcription factors in V0v cells. Methods To identify candidate members of V0v gene regulatory networks, we FAC-sorted WT and evx1;evx2 double mutant zebrafish V0v spinal interneurons and expression-profiled them using microarrays and single cell RNA-seq. We also used in situ hybridization to compare expression of a subset of candidate genes in evx1;evx2 double mutants and wild-type siblings. Results Our data reveal two molecularly distinct subtypes of V0v spinal interneurons at 48 h and suggest that, by this stage of development, evx1;evx2 double mutant cells transfate into either inhibitory spinal interneurons, or motoneurons. Our results also identify 25 transcriptional regulator genes that require Evx1/2 for their expression in V0v interneurons, plus a further 11 transcriptional regulator genes that are repressed in V0v interneurons by Evx1/2. Two of the latter genes are hmx2 and hmx3a. Intriguingly, we show that Hmx2/3a, repress dI2 interneuronal expression of skor1a and nefma, two genes that require Evx1/2 for their expression in V0v interneurons. This suggests that Evx1/2 might regulate skor1a and nefma expression in V0v interneurons by repressing Hmx2/3a expression. Conclusions This study identifies two molecularly distinct subsets of V0v spinal interneurons, as well as multiple transcriptional regulators that are strong candidates for acting downstream of Evx1/2 to specify the essential functional characteristics of these cells. Our data further suggest that in the absence of both Evx1 and Evx2, V0v spinal interneurons initially change their neurotransmitter phenotypes from excitatory to inhibitory and then, later, start to express markers of distinct types of inhibitory spinal interneurons, or motoneurons. Taken together, our findings significantly increase our knowledge of V0v and spinal development and move us closer towards the essential goal of identifying the complete gene regulatory networks that specify this crucial cell type.
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Needham J, Metzis V. Heads or tails: Making the spinal cord. Dev Biol 2022; 485:80-92. [DOI: 10.1016/j.ydbio.2022.03.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 12/15/2021] [Accepted: 03/02/2022] [Indexed: 12/14/2022]
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Wilmerding A, Bouteille L, Rinaldi L, Caruso N, Graba Y, Delfini MC. HOXB8 Counteracts MAPK/ERK Oncogenic Signaling in a Chicken Embryo Model of Neoplasia. Int J Mol Sci 2021; 22:8911. [PMID: 34445617 PMCID: PMC8396257 DOI: 10.3390/ijms22168911] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/18/2021] [Accepted: 07/29/2021] [Indexed: 12/12/2022] Open
Abstract
HOX transcription factors are members of an evolutionarily conserved family of proteins required for the establishment of the anteroposterior body axis during bilaterian development. Although they are often deregulated in cancers, the molecular mechanisms by which they act as oncogenes or tumor suppressor genes are only partially understood. Since the MAPK/ERK signaling pathway is deregulated in most cancers, we aimed at apprehending if and how the Hox proteins interact with ERK oncogenicity. Using an in vivo neoplasia model in the chicken embryo consisting in the overactivation of the ERK1/2 kinases in the trunk neural tube, we analyzed the consequences of the HOXB8 gain of function at the morphological and transcriptional levels. We found that HOXB8 acts as a tumor suppressor, counteracting ERK-induced neoplasia. The HOXB8 tumor suppressor function relies on a large reversion of the oncogenic transcriptome induced by ERK. In addition to showing that the HOXB8 protein controls the transcriptional responsiveness to ERK oncogenic signaling, our study identified new downstream targets of ERK oncogenic activation in an in vivo context that could provide clues for therapeutic strategies.
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Affiliation(s)
- Axelle Wilmerding
- Aix Marseille Université (AMU), Centre National de la Recherche Scientifique (CNRS), Institut de Biologie du Développement de Marseille (IBDM-UMR 7288), 13288 Marseille, France; (A.W.); (L.B.); (L.R.); (N.C.)
| | - Lauranne Bouteille
- Aix Marseille Université (AMU), Centre National de la Recherche Scientifique (CNRS), Institut de Biologie du Développement de Marseille (IBDM-UMR 7288), 13288 Marseille, France; (A.W.); (L.B.); (L.R.); (N.C.)
| | - Lucrezia Rinaldi
- Aix Marseille Université (AMU), Centre National de la Recherche Scientifique (CNRS), Institut de Biologie du Développement de Marseille (IBDM-UMR 7288), 13288 Marseille, France; (A.W.); (L.B.); (L.R.); (N.C.)
- Beth Israel Deaconess Medical Center, Department of Medicine and the Cancer Center, Division of Hematology, Harvard Initiative of RNA Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Nathalie Caruso
- Aix Marseille Université (AMU), Centre National de la Recherche Scientifique (CNRS), Institut de Biologie du Développement de Marseille (IBDM-UMR 7288), 13288 Marseille, France; (A.W.); (L.B.); (L.R.); (N.C.)
| | - Yacine Graba
- Aix Marseille Université (AMU), Centre National de la Recherche Scientifique (CNRS), Institut de Biologie du Développement de Marseille (IBDM-UMR 7288), 13288 Marseille, France; (A.W.); (L.B.); (L.R.); (N.C.)
| | - Marie-Claire Delfini
- Aix Marseille Université (AMU), Centre National de la Recherche Scientifique (CNRS), Institut de Biologie du Développement de Marseille (IBDM-UMR 7288), 13288 Marseille, France; (A.W.); (L.B.); (L.R.); (N.C.)
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Zebrafish Cdx4 regulates neural crest cell specification and migratory behaviors in the posterior body. Dev Biol 2021; 480:25-38. [PMID: 34389276 DOI: 10.1016/j.ydbio.2021.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 07/17/2021] [Accepted: 08/09/2021] [Indexed: 02/07/2023]
Abstract
The neural crest (NC) is a transient multipotent cell population that migrates extensively to produce a remarkable array of vertebrate cell types. NC cell specification progresses in an anterior to posterior fashion, resulting in distinct, axial-restricted subpopulations. The anterior-most, cranial, population of NC is specified as gastrulation concludes and neurulation begins, while more posterior populations become specified as the body elongates. The mechanisms that govern development of the more posterior NC cells remain incompletely understood. Here, we report a key role for zebrafish Cdx4, a homeodomain transcription factor, in the development of posterior NC cells. We demonstrate that cdx4 is expressed in trunk NC cell progenitors, directly binds NC cell-specific enhancers in the NC GRN, and regulates expression of the key NC development gene foxd3 in the posterior body. Moreover, cdx4 mutants show disruptions to the segmental pattern of trunk NC cell migration due to loss of normal leader/follower cell dynamics. Finally, using cell transplantation to generate chimeric specimens, we show that Cdx4 does not function in the paraxial mesoderm-the environment adjacent to which crest migrates-to influence migratory behaviors. We conclude that cdx4 plays a critical, and likely tissue autonomous, role in the establishment of trunk NC migratory behaviors. Together, our results indicate that cdx4 functions as an early NC specifier gene in the posterior body of zebrafish embryos.
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Itoh T, Takeuchi M, Sakagami M, Asakawa K, Sumiyama K, Kawakami K, Shimizu T, Hibi M. Gsx2 is required for specification of neurons in the inferior olivary nuclei from Ptf1a-expressing neural progenitors in zebrafish. Development 2020; 147:dev.190603. [PMID: 32928905 DOI: 10.1242/dev.190603] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 09/03/2020] [Indexed: 11/20/2022]
Abstract
Neurons in the inferior olivary nuclei (IO neurons) send climbing fibers to Purkinje cells to elicit functions of the cerebellum. IO neurons and Purkinje cells are derived from neural progenitors expressing the proneural gene ptf1a In this study, we found that the homeobox gene gsx2 was co-expressed with ptf1a in IO progenitors in zebrafish. Both gsx2 and ptf1a zebrafish mutants showed a strong reduction or loss of IO neurons. The expression of ptf1a was not affected in gsx2 mutants, and vice versa. In IO progenitors, the ptf1a mutation increased apoptosis whereas the gsx2 mutation did not, suggesting that ptf1a and gsx2 are regulated independently of each other and have distinct roles. The fibroblast growth factors (Fgf) 3 and 8a, and retinoic acid signals negatively and positively, respectively, regulated gsx2 expression and thereby the development of IO neurons. mafba and Hox genes are at least partly involved in the Fgf- and retinoic acid-dependent regulation of IO neuronal development. Our results indicate that gsx2 mediates the rostro-caudal positional signals to specify the identity of IO neurons from ptf1a-expressing neural progenitors.
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Affiliation(s)
- Tsubasa Itoh
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo, Chikusa, Nagoya, Aichi 464-8602, Japan
| | - Miki Takeuchi
- Bioscience and Biotechnology Center, Nagoya University, Furo, Chikusa, Nagoya, Aichi 464-8601, Japan
| | - Marina Sakagami
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo, Chikusa, Nagoya, Aichi 464-8602, Japan
| | - Kazuhide Asakawa
- Laboratory of Molecular and Developmental Biology, National Institute of Genetics, Department of Genetics, SOKENDAI (The Graduate University for Advanced Studies), Mishima, 411-8540, Japan
| | - Kenta Sumiyama
- RIKEN Center for Biosystems Dynamics Research (BDR), Suita, Osaka 565-0871, Japan
| | - Koichi Kawakami
- Laboratory of Molecular and Developmental Biology, National Institute of Genetics, Department of Genetics, SOKENDAI (The Graduate University for Advanced Studies), Mishima, 411-8540, Japan
| | - Takashi Shimizu
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo, Chikusa, Nagoya, Aichi 464-8602, Japan.,Bioscience and Biotechnology Center, Nagoya University, Furo, Chikusa, Nagoya, Aichi 464-8601, Japan
| | - Masahiko Hibi
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo, Chikusa, Nagoya, Aichi 464-8602, Japan .,Bioscience and Biotechnology Center, Nagoya University, Furo, Chikusa, Nagoya, Aichi 464-8601, Japan
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9
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The Cdx transcription factors and retinoic acid play parallel roles in antero-posterior position of the pectoral fin field during gastrulation. Mech Dev 2020; 164:103644. [PMID: 32911082 DOI: 10.1016/j.mod.2020.103644] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 09/01/2020] [Accepted: 09/02/2020] [Indexed: 12/27/2022]
Abstract
The molecular regulators that determine the precise position of the vertebrate limb along the anterio-posterior axis have not been identified. One model suggests that a combination of hox genes in the lateral plate mesoderm (LPM) promotes formation of the limb field, however redundancy among duplicated paralogs has made this model difficult to confirm. In this study, we identify an optimal window during mid-gastrulation stages when transient mis-regulation of retinoic acid signaling or the caudal related transcription factor, Cdx4, both known regulators of hox genes, can alter the position of the pectoral fin field. We show that increased levels of either RA or Cdx4 during mid-gastrulation are sufficient to rostrally shift the position of the pectoral fin field at the expense of surrounding gene expression in the anterior lateral plate mesoderm (aLPM). Alternatively, embryos deficient for both Cdx4 and Cdx1a (Cdx-deficient) form pectoral fins that are shifted towards the posterior and reveal an additional effect on size of the pectoral fin buds. Prior to formation of the pectoral fin buds, the fin field in Cdx-deficient embryos is visibly expanded into the posterior LPM (pLPM) region at the expense of surrounding gene expression. The effects on gene expression immediately post-gastrulation and during somitogenesis support a model where RA and Cdx4 act in parallel to regulate the position of the pectoral fin. Our transient method is a potentially useful model for studying the mechanisms of limb positioning along the AP axis.
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Rhodes CS, Matsunobu T, Yamada Y. Analysis of a limb-specific regulatory element in the promoter of the link protein gene. Biochem Biophys Res Commun 2019; 518:672-677. [PMID: 31470976 PMCID: PMC10505274 DOI: 10.1016/j.bbrc.2019.08.104] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 08/19/2019] [Indexed: 11/30/2022]
Abstract
Link protein is encoded by the Hapln1 gene and is a prototypical protein found in the cartilage matrix. It acts as an important component of the endochondral skeleton during early development. To study its transcriptional regulation, promoter fragments derived from the link protein gene were coupled to the β-galactosidase reporter and used to study in vivo transgene expression in mice. In day 15.5 mouse embryos, a link promoter fragment spanning -1020 to +40 nucleotides demonstrated highly specific β-galactosidase staining of skeletal structures, including the appendicular and axial cartilaginous tissues. Two shorter promoter fragments, spanning -690 to +40 and -315 to +40 nucleotides, demonstrated limb- and genitalia-specific expression resembling that of homeodomain-regulated tissues. Bioinformatic analysis revealed a highly conserved, Hox-like binding site (HLBS) at approximately -220 bp of the promoter, shared by both constructs, which contained the Hox-core consensus sequence TAATTA. Electromobility shift assays demonstrated binding of Hox-B4 recombinant protein to the HLBS, which was eliminated with nucleotide substitutions within the core-binding element. Co-transfection analysis of the HLBS demonstrated a 22-fold transcriptional activation by HoxA9 expression, which was ablated with a substitution within the core HLBS element. Together these findings establish promoter regions within the link protein gene that are important for in vivo expression and identify the potential role of homeodomain-containing proteins in controlling cartilage and limb gene expression.
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Affiliation(s)
- Craig S Rhodes
- Molecular Biology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Tomoya Matsunobu
- Department of Orthopaedic Surgery, Kyushu Rosai Hospital, 1-1 Sonekitamachi, Kokuraminami-ku, Kitakyushu, Fukuoka, 800-0296, Japan
| | - Yoshihiko Yamada
- Molecular Biology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
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Polevoy H, Gutkovich YE, Michaelov A, Volovik Y, Elkouby YM, Frank D. New roles for Wnt and BMP signaling in neural anteroposterior patterning. EMBO Rep 2019; 20:embr.201845842. [PMID: 30936121 DOI: 10.15252/embr.201845842] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 03/04/2019] [Accepted: 03/07/2019] [Indexed: 01/19/2023] Open
Abstract
During amphibian development, neural patterning occurs via a two-step process. Spemann's organizer secretes BMP antagonists that induce anterior neural tissue. A subsequent caudalizing step re-specifies anterior fated cells to posterior fates such as hindbrain and spinal cord. The neural patterning paradigm suggests that a canonical Wnt-signaling gradient acts along the anteroposterior axis to pattern the nervous system. Wnt activity is highest in the posterior, inducing spinal cord, at intermediate levels in the trunk, inducing hindbrain, and is lowest in anterior fated forebrain, while BMP-antagonist levels are constant along the axis. Our results in Xenopus laevis challenge this paradigm. We find that inhibition of canonical Wnt signaling or its downstream transcription factors eliminates hindbrain, but not spinal cord fates, an observation not compatible with a simple high-to-low Wnt gradient specifying all fates along the neural anteroposterior axis. Additionally, we find that BMP activity promotes posterior spinal cord cell fate formation in an FGF-dependent manner, while inhibiting hindbrain fates. These results suggest a need to re-evaluate the paradigms of neural anteroposterior pattern formation during vertebrate development.
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Affiliation(s)
- Hanna Polevoy
- Department of Biochemistry, Faculty of Medicine, The Rappaport Family Institute for Research in the Medical Sciences, Technion - Israel Institute of Technology, Haifa, Israel
| | - Yoni E Gutkovich
- Department of Biochemistry, Faculty of Medicine, The Rappaport Family Institute for Research in the Medical Sciences, Technion - Israel Institute of Technology, Haifa, Israel
| | - Ariel Michaelov
- Department of Biochemistry, Faculty of Medicine, The Rappaport Family Institute for Research in the Medical Sciences, Technion - Israel Institute of Technology, Haifa, Israel
| | - Yael Volovik
- Department of Biochemistry, Faculty of Medicine, The Rappaport Family Institute for Research in the Medical Sciences, Technion - Israel Institute of Technology, Haifa, Israel
| | - Yaniv M Elkouby
- Department of Biochemistry, Faculty of Medicine, The Rappaport Family Institute for Research in the Medical Sciences, Technion - Israel Institute of Technology, Haifa, Israel
| | - Dale Frank
- Department of Biochemistry, Faculty of Medicine, The Rappaport Family Institute for Research in the Medical Sciences, Technion - Israel Institute of Technology, Haifa, Israel
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Frank D, Sela-Donenfeld D. Hindbrain induction and patterning during early vertebrate development. Cell Mol Life Sci 2019; 76:941-960. [PMID: 30519881 PMCID: PMC11105337 DOI: 10.1007/s00018-018-2974-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 11/19/2018] [Accepted: 11/21/2018] [Indexed: 12/28/2022]
Abstract
The hindbrain is a key relay hub of the central nervous system (CNS), linking the bilaterally symmetric half-sides of lower and upper CNS centers via an extensive network of neural pathways. Dedicated neural assemblies within the hindbrain control many physiological processes, including respiration, blood pressure, motor coordination and different sensations. During early development, the hindbrain forms metameric segmented units known as rhombomeres along the antero-posterior (AP) axis of the nervous system. These compartmentalized units are highly conserved during vertebrate evolution and act as the template for adult brainstem structure and function. TALE and HOX homeodomain family transcription factors play a key role in the initial induction of the hindbrain and its specification into rhombomeric cell fate identities along the AP axis. Signaling pathways, such as canonical-Wnt, FGF and retinoic acid, play multiple roles to initially induce the hindbrain and regulate Hox gene-family expression to control rhombomeric identity. Additional transcription factors including Krox20, Kreisler and others act both upstream and downstream to Hox genes, modulating their expression and protein activity. In this review, we will examine the earliest embryonic signaling pathways that induce the hindbrain and subsequent rhombomeric segmentation via Hox and other gene expression. We will examine how these signaling pathways and transcription factors interact to activate downstream targets that organize the segmented AP pattern of the embryonic vertebrate hindbrain.
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Affiliation(s)
- Dale Frank
- Department of Biochemistry, Faculty of Medicine, The Rappaport Family Institute for Research in the Medical Sciences, Technion-Israel Institute of Technology, 31096, Haifa, Israel.
| | - Dalit Sela-Donenfeld
- Koret School of Veterinary Medicine, The Robert H Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, 76100, Rehovot, Israel.
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Joshi P, Darr AJ, Skromne I. CDX4 regulates the progression of neural maturation in the spinal cord. Dev Biol 2019; 449:132-142. [PMID: 30825428 DOI: 10.1016/j.ydbio.2019.02.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Revised: 02/25/2019] [Accepted: 02/25/2019] [Indexed: 11/17/2022]
Abstract
The progression of cells down different lineage pathways is a collaborative effort between networks of extracellular signals and intracellular transcription factors. In the vertebrate spinal cord, FGF, Wnt and Retinoic Acid signaling pathways regulate the progressive caudal-to-rostral maturation of neural progenitors by regulating a poorly understood gene regulatory network of transcription factors. We have mapped out this gene regulatory network in the chicken pre-neural tube, identifying CDX4 as a dual-function core component that simultaneously regulates gradual loss of cell potency and acquisition of differentiation states: in a caudal-to-rostral direction, CDX4 represses the early neural differentiation marker Nkx1.2 and promotes the late neural differentiation marker Pax6. Significantly, CDX4 prevents premature PAX6-dependent neural differentiation by blocking Ngn2 activation. This regulation of CDX4 over Pax6 is restricted to the rostral pre-neural tube by Retinoic Acid signaling. Together, our results show that in the spinal cord, CDX4 is part of the gene regulatory network controlling the sequential and progressive transition of states from high to low potency during neural progenitor maturation. Given CDX well-known involvement in Hox gene regulation, we propose that CDX factors coordinate the maturation and axial specification of neural progenitor cells during spinal cord development.
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Affiliation(s)
- Piyush Joshi
- Department of Biology, University of Miami, 1301 Memorial Drive, Coral Gables, Florida, 33146, United States; Cancer and Blood Disorders Institute, Johns Hopkins All Children's Hospital, 600 5th St S, St. Petersburg, FL 33701, United States
| | - Andrew J Darr
- Department of Health Sciences Education, University of Illinois College of Medicine, 1 Illini Drive, Peoria, IL 61605, United States
| | - Isaac Skromne
- Department of Biology, University of Miami, 1301 Memorial Drive, Coral Gables, Florida, 33146, United States; Department of Biology, University of Richmond, 138 UR Drive B322, Richmond, VA, 23173, United States.
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14
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Kindt LM, Coughlin AR, Perosino TR, Ersfeld HN, Hampton M, Liang JO. Identification of transcripts potentially involved in neural tube closure using RNA sequencing. Genesis 2018; 56:e23096. [PMID: 29488319 DOI: 10.1002/dvg.23096] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2017] [Revised: 02/02/2018] [Accepted: 02/19/2018] [Indexed: 01/08/2023]
Abstract
Anencephaly is a fatal human neural tube defect (NTD) in which the anterior neural tube remains open. Zebrafish embryos with reduced Nodal signaling display an open anterior neural tube phenotype that is analogous to anencephaly. Previous work from our laboratory suggests that Nodal signaling acts through induction of the head mesendoderm and mesoderm. Head mesendoderm/mesoderm then, through an unknown mechanism, promotes formation of the polarized neuroepithelium that is capable of undergoing the movements required for closure. We compared the transcriptome of embryos treated with a Nodal signaling inhibitor at sphere stage, which causes NTDs, to embryos treated at 30% epiboly, which does not cause NTDs. This screen identified over 3,000 transcripts with potential roles in anterior neurulation. Expression of several genes encoding components of tight and adherens junctions was significantly reduced, supporting the model that Nodal signaling regulates formation of the neuroepithelium. mRNAs involved in Wnt, FGF, and BMP signaling were also differentially expressed, suggesting these pathways might regulate anterior neurulation. In support of this, we found that pharmacological inhibition of FGF-receptor function causes an open anterior NTD as well as loss of mesodermal derivatives. This suggests that Nodal and FGF signaling both promote anterior neurulation through induction of head mesoderm.
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Affiliation(s)
- Lexy M Kindt
- Department of Biology, University of Minnesota Duluth, Duluth.,Integrated Biosciences Graduate Program, University of Minnesota, Duluth
| | - Alicia R Coughlin
- Department of Biology, University of Minnesota Duluth, Duluth.,Integrated Biosciences Graduate Program, University of Minnesota, Duluth
| | | | - Haley N Ersfeld
- Department of Biology, University of Minnesota Duluth, Duluth
| | - Marshall Hampton
- Integrated Biosciences Graduate Program, University of Minnesota, Duluth.,Department of Mathematics and Statistics, University of Minnesota Duluth, Duluth
| | - Jennifer O Liang
- Department of Biology, University of Minnesota Duluth, Duluth.,Integrated Biosciences Graduate Program, University of Minnesota, Duluth
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15
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Brafman D, Willert K. Wnt/β-catenin signaling during early vertebrate neural development. Dev Neurobiol 2017; 77:1239-1259. [PMID: 28799266 DOI: 10.1002/dneu.22517] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/24/2017] [Accepted: 08/09/2017] [Indexed: 12/29/2022]
Abstract
The vertebrate central nervous system (CNS) is comprised of vast number of distinct cell types arranged in a highly organized manner. This high degree of complexity is achieved by cellular communication, including direct cell-cell contact, cell-matrix interactions, and cell-growth factor signaling. Among the several developmental signals controlling the development of the CNS, Wnt proteins have emerged as particularly critical and, hence, have captivated the attention of many researchers. With Wnts' evolutionarily conserved function as primordial symmetry breaking signals, these proteins and their downstream effects are responsible for simultaneously establishing cellular diversity and tissue organization. With their expansive repertoire of secreted agonists and antagonists, cell surface receptors, signaling cascades and downstream biological effects, Wnts are ideally suited to control the complex processes underlying vertebrate neural development. In this review, we will describe the mechanisms by which Wnts exert their potent effects on cells and tissues and highlight the many roles of Wnt signaling during neural development, starting from the initial induction of the neural plate, the subsequent patterning along the embryonic axes, to the intricately organized structure of the CNS. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 77: 1239-1259, 2017.
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Affiliation(s)
- David Brafman
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, Arizona, 85287
| | - Karl Willert
- Department of Cellular & Molecular Medicine, University of California San Diego, La Jolla, CA, 92093-0695
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16
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A Hox complex activates and potentiates the Epidermal Growth Factor signaling pathway to specify Drosophila oenocytes. PLoS Genet 2017; 13:e1006910. [PMID: 28715417 PMCID: PMC5536354 DOI: 10.1371/journal.pgen.1006910] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 07/31/2017] [Accepted: 07/06/2017] [Indexed: 11/19/2022] Open
Abstract
Hox transcription factors specify distinct cell types along the anterior-posterior axis of metazoans by regulating target genes that modulate signaling pathways. A well-established example is the induction of Epidermal Growth Factor (EGF) signaling by an Abdominal-A (Abd-A) Hox complex during the specification of Drosophila hepatocyte-like cells (oenocytes). Previous studies revealed that Abd-A is non-cell autonomously required to promote oenocyte fate by directly activating a gene (rhomboid) that triggers EGF secretion from sensory organ precursor (SOP) cells. Neighboring cells that receive the EGF signal initiate a largely unknown pathway to promote oenocyte fate. Here, we show that Abd-A also plays a cell autonomous role in inducing oenocyte fate by activating the expression of the Pointed-P1 (PntP1) ETS transcription factor downstream of EGF signaling. Genetic studies demonstrate that both PntP1 and PntP2 are required for oenocyte specification. Moreover, we found that PntP1 contains a conserved enhancer (PntP1OE) that is activated in oenocyte precursor cells by EGF signaling via direct regulation by the Pnt transcription factors as well as a transcription factor complex consisting of Abd-A, Extradenticle, and Homothorax. Our findings demonstrate that the same Abd-A Hox complex required for sending the EGF signal from SOP cells, enhances the competency of receiving cells to select oenocyte cell fate by up-regulating PntP1. Since PntP1 is a downstream effector of EGF signaling, these findings provide insight into how a Hox factor can both trigger and potentiate the EGF signal to promote an essential cell fate along the body plan.
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17
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Abstract
During vertebrate embryonic development, the spinal cord is formed by the neural derivatives of a neuromesodermal population that is specified at early stages of development and which develops in concert with the caudal regression of the primitive streak. Several processes related to spinal cord specification and maturation are coupled to this caudal extension including neurogenesis, ventral patterning and neural crest specification and all of them seem to be crucially regulated by Fibroblast Growth Factor (FGF) signaling, which is prominently active in the neuromesodermal region and transiently in its derivatives. Here we review the role of FGF signaling in those processes, trying to separate its different functions and highlighting the interactions with other signaling pathways. Finally, these early functions of FGF signaling in spinal cord development may underlay partly its ability to promote regeneration in the lesioned spinal cord as well as its action promoting specific fates in neural stem cell cultures that may be used for therapeutical purposes.
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Affiliation(s)
- Ruth Diez Del Corral
- Department of Cellular, Molecular and Developmental Neurobiology, Cajal Institute, Consejo Superior de Investigaciones CientíficasMadrid, Spain.,Champalimaud Research, Champalimaud Centre for the UnknownLisbon, Portugal
| | - Aixa V Morales
- Department of Cellular, Molecular and Developmental Neurobiology, Cajal Institute, Consejo Superior de Investigaciones CientíficasMadrid, Spain
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18
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New Insights Into the Roles of Retinoic Acid Signaling in Nervous System Development and the Establishment of Neurotransmitter Systems. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 330:1-84. [PMID: 28215529 DOI: 10.1016/bs.ircmb.2016.09.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Secreted chiefly from the underlying mesoderm, the morphogen retinoic acid (RA) is well known to contribute to the specification, patterning, and differentiation of neural progenitors in the developing vertebrate nervous system. Furthermore, RA influences the subtype identity and neurotransmitter phenotype of subsets of maturing neurons, although relatively little is known about how these functions are mediated. This review provides a comprehensive overview of the roles played by RA signaling during the formation of the central and peripheral nervous systems of vertebrates and highlights its effects on the differentiation of several neurotransmitter systems. In addition, the evolutionary history of the RA signaling system is discussed, revealing both conserved properties and alternate modes of RA action. It is proposed that comparative approaches should be employed systematically to expand our knowledge of the context-dependent cellular mechanisms controlled by the multifunctional signaling molecule RA.
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19
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Rankin SA, Han L, McCracken KW, Kenny AP, Anglin CT, Grigg EA, Crawford CM, Wells JM, Shannon JM, Zorn AM. A Retinoic Acid-Hedgehog Cascade Coordinates Mesoderm-Inducing Signals and Endoderm Competence during Lung Specification. Cell Rep 2016; 16:66-78. [PMID: 27320915 PMCID: PMC5314425 DOI: 10.1016/j.celrep.2016.05.060] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 04/13/2016] [Accepted: 05/16/2016] [Indexed: 12/15/2022] Open
Abstract
Organogenesis of the trachea and lungs requires a complex series of mesoderm-endoderm interactions mediated by WNT, BMP, retinoic acid (RA), and hedgehog (Hh), but how these pathways interact in a gene regulatory network is less clear. Using Xenopus embryology, mouse genetics, and human ES cell cultures, we identified a conserved signaling cascade that initiates respiratory lineage specification. We show that RA has multiple roles; first RA pre-patterns the lateral plate mesoderm and then it promotes Hh ligand expression in the foregut endoderm. Hh subsequently signals back to the pre-patterned mesoderm to promote expression of the lung-inducing ligands Wnt2/2b and Bmp4. Finally, RA regulates the competence of the endoderm to activate the Nkx2-1+ respiratory program in response to these mesodermal WNT and BMP signals. These data provide insights into early lung development and a paradigm for how mesenchymal signals are coordinated with epithelial competence during organogenesis.
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Affiliation(s)
- Scott A Rankin
- Division of Developmental Biology, Department of Pediatrics, Perinatal Institute and Cincinnati Children's Hospital, College of Medicine, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Lu Han
- Division of Developmental Biology, Department of Pediatrics, Perinatal Institute and Cincinnati Children's Hospital, College of Medicine, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Kyle W McCracken
- Division of Developmental Biology, Department of Pediatrics, Perinatal Institute and Cincinnati Children's Hospital, College of Medicine, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Alan P Kenny
- Division of Neonatology, Department of Pediatrics, Perinatal Institute and Cincinnati Children's Hospital, College of Medicine, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Christopher T Anglin
- Division of Developmental Biology, Department of Pediatrics, Perinatal Institute and Cincinnati Children's Hospital, College of Medicine, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Emily A Grigg
- Division of Developmental Biology, Department of Pediatrics, Perinatal Institute and Cincinnati Children's Hospital, College of Medicine, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Calyn M Crawford
- Division of Developmental Biology, Department of Pediatrics, Perinatal Institute and Cincinnati Children's Hospital, College of Medicine, University of Cincinnati, Cincinnati, OH 45229, USA
| | - James M Wells
- Division of Developmental Biology, Department of Pediatrics, Perinatal Institute and Cincinnati Children's Hospital, College of Medicine, University of Cincinnati, Cincinnati, OH 45229, USA
| | - John M Shannon
- Division of Pulmonary Biology, Department of Pediatrics, Perinatal Institute and Cincinnati Children's Hospital, College of Medicine, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Aaron M Zorn
- Division of Developmental Biology, Department of Pediatrics, Perinatal Institute and Cincinnati Children's Hospital, College of Medicine, University of Cincinnati, Cincinnati, OH 45229, USA.
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20
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Sanchez-Ferras O, Bernas G, Farnos O, Touré AM, Souchkova O, Pilon N. A direct role for murine Cdx proteins in the trunk neural crest gene regulatory network. Development 2016; 143:1363-74. [PMID: 26952979 DOI: 10.1242/dev.132159] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 02/18/2016] [Indexed: 12/28/2022]
Abstract
Numerous studies in chordates and arthropods currently indicate that Cdx proteins have a major ancestral role in the organization of post-head tissues. In urochordate embryos, Cdx loss-of-function has been shown to impair axial elongation, neural tube (NT) closure and pigment cell development. Intriguingly, in contrast to axial elongation and NT closure, a Cdx role in neural crest (NC)-derived melanocyte/pigment cell development has not been reported in any other chordate species. To address this, we generated a new conditional pan-Cdx functional knockdown mouse model that circumvents Cdx functional redundancy as well as the early embryonic lethality of Cdx mutants. Through directed inhibition in the neuroectoderm, we provide in vivo evidence that murine Cdx proteins impact melanocyte and enteric nervous system development by, at least in part, directly controlling the expression of the key early regulators of NC ontogenesis Pax3,Msx1 and Foxd3 Our work thus reveals a novel role for Cdx proteins at the top of the trunk NC gene regulatory network in the mouse, which appears to have been inherited from their ancestral ortholog.
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Affiliation(s)
- Oraly Sanchez-Ferras
- Molecular Genetics of Development Laboratory, Department of Biological Sciences and BioMed Research Center, University of Quebec at Montreal (UQAM), Montreal H2X 3Y7, Canada
| | - Guillaume Bernas
- Molecular Genetics of Development Laboratory, Department of Biological Sciences and BioMed Research Center, University of Quebec at Montreal (UQAM), Montreal H2X 3Y7, Canada
| | - Omar Farnos
- Molecular Genetics of Development Laboratory, Department of Biological Sciences and BioMed Research Center, University of Quebec at Montreal (UQAM), Montreal H2X 3Y7, Canada
| | - Aboubacrine M Touré
- Molecular Genetics of Development Laboratory, Department of Biological Sciences and BioMed Research Center, University of Quebec at Montreal (UQAM), Montreal H2X 3Y7, Canada
| | - Ouliana Souchkova
- Molecular Genetics of Development Laboratory, Department of Biological Sciences and BioMed Research Center, University of Quebec at Montreal (UQAM), Montreal H2X 3Y7, Canada
| | - Nicolas Pilon
- Molecular Genetics of Development Laboratory, Department of Biological Sciences and BioMed Research Center, University of Quebec at Montreal (UQAM), Montreal H2X 3Y7, Canada
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21
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Chang J, Skromne I, Ho RK. CDX4 and retinoic acid interact to position the hindbrain-spinal cord transition. Dev Biol 2016; 410:178-189. [PMID: 26773000 DOI: 10.1016/j.ydbio.2015.12.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 12/17/2015] [Accepted: 12/23/2015] [Indexed: 12/15/2022]
Abstract
The sub-division of the posterior-most territory of the neural plate results in the formation of two distinct neural structures, the hindbrain and the spinal cord. Although many of the molecular signals regulating the development of these individual structures have been elucidated, the mechanisms involved in delineating the boundary between the hindbrain and spinal cord remain elusive. Two molecules, retinoic acid (RA) and the Cdx4 transcription factor have been previously implicated as important regulators of hindbrain and spinal cord development, respectively. Here, we provide evidence that suggests multiple regulatory interactions occur between RA signaling and the Cdx4 transcription factor to establish the anterior-posterior (AP) position of the transition between the hindbrain and spinal cord. Using chemical inhibitors to alter RA concentrations and morpholinos to knock-down Cdx4 function in zebrafish, we show that Cdx4 acts to prevent RA degradation in the presumptive spinal cord domain by suppressing expression of the RA degradation enzyme, Cyp26a1. In the hindbrain, RA signaling modulates its own concentration by activating the expression of cyp26a1 and inhibiting the expansion of cdx4. Therefore, interactions between Cyp26a1 and Cdx4 modulate RA levels along the AP axis to segregate the posterior neural plate into the hindbrain and spinal cord territories.
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Affiliation(s)
- Jessie Chang
- Committee on Developmental Biology, University of Chicago, Chicago, IL 60637, USA
| | - Isaac Skromne
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA
| | - Robert K Ho
- Department of Organismal Biology and Anatomy, University of Chicago, 1027 E. 57th St, Chicago, IL 60637, USA.
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22
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Zhang T, Xu L, Wu JJ, Wang WM, Mei J, Ma XF, Liu JX. Transcriptional Responses and Mechanisms of Copper-Induced Dysfunctional Locomotor Behavior in Zebrafish Embryos. Toxicol Sci 2015; 148:299-310. [DOI: 10.1093/toxsci/kfv184] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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23
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Marlétaz F, Maeso I, Faas L, Isaacs HV, Holland PWH. Cdx ParaHox genes acquired distinct developmental roles after gene duplication in vertebrate evolution. BMC Biol 2015; 13:56. [PMID: 26231746 PMCID: PMC4522105 DOI: 10.1186/s12915-015-0165-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 07/08/2015] [Indexed: 01/03/2023] Open
Abstract
Background The functional consequences of whole genome duplications in vertebrate evolution are not fully understood. It remains unclear, for instance, why paralogues were retained in some gene families but extensively lost in others. Cdx homeobox genes encode conserved transcription factors controlling posterior development across diverse bilaterians. These genes are part of the ParaHox gene cluster. Multiple Cdx copies were retained after genome duplication, raising questions about how functional divergence, overlap, and redundancy respectively contributed to their retention and evolutionary fate. Results We examined the degree of regulatory and functional overlap between the three vertebrate Cdx genes using single and triple morpholino knock-down in Xenopus tropicalis followed by RNA-seq. We found that one paralogue, Cdx4, has a much stronger effect on gene expression than the others, including a strong regulatory effect on FGF and Wnt genes. Functional annotation revealed distinct and overlapping roles and subtly different temporal windows of action for each gene. The data also reveal a colinear-like effect of Cdx genes on Hox genes, with repression of Hox paralogy groups 1 and 2, and activation increasing from Hox group 5 to 11. We also highlight cases in which duplicated genes regulate distinct paralogous targets revealing pathway elaboration after whole genome duplication. Conclusions Despite shared core pathways, Cdx paralogues have acquired distinct regulatory roles during development. This implies that the degree of functional overlap between paralogues is relatively low and that gene expression pattern alone should be used with caution when investigating the functional evolution of duplicated genes. We therefore suggest that developmental programmes were extensively rewired after whole genome duplication in the early evolution of vertebrates. Electronic supplementary material The online version of this article (doi:10.1186/s12915-015-0165-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ferdinand Marlétaz
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK.
| | - Ignacio Maeso
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK. .,Present address: Centro Andaluz de Biología del Desarrollo (CABD), Consejo Superior de Investigaciones Científicas/Universidad Pablo de Olavide, Sevilla, Spain.
| | - Laura Faas
- Department of Biology, University of York, Heslington, York, YO10 5DD, UK.
| | - Harry V Isaacs
- Department of Biology, University of York, Heslington, York, YO10 5DD, UK.
| | - Peter W H Holland
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK.
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Cunningham TJ, Duester G. Mechanisms of retinoic acid signalling and its roles in organ and limb development. Nat Rev Mol Cell Biol 2015; 16:110-23. [PMID: 25560970 PMCID: PMC4636111 DOI: 10.1038/nrm3932] [Citation(s) in RCA: 387] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Retinoic acid (RA) signalling has a central role during vertebrate development. RA synthesized in specific locations regulates transcription by interacting with nuclear RA receptors (RARs) bound to RA response elements (RAREs) near target genes. RA was first implicated in signalling on the basis of its teratogenic effects on limb development. Genetic studies later revealed that endogenous RA promotes forelimb initiation by repressing fibroblast growth factor 8 (Fgf8). Insights into RA function in the limb serve as a paradigm for understanding how RA regulates other developmental processes. In vivo studies have identified RAREs that control repression of Fgf8 during body axis extension or activation of homeobox (Hox) genes and other key regulators during neuronal differentiation and organogenesis.
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Affiliation(s)
- Thomas J Cunningham
- Development, Aging, and Regeneration Program, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Road, La Jolla, California 92037, USA
| | - Gregg Duester
- Development, Aging, and Regeneration Program, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Road, La Jolla, California 92037, USA
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25
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Lee K, Skromne I. Retinoic acid regulates size, pattern and alignment of tissues at the head-trunk transition. Development 2015; 141:4375-84. [PMID: 25371368 DOI: 10.1242/dev.109603] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
At the head-trunk transition, hindbrain and spinal cord alignment to occipital and vertebral bones is crucial for coherent neural and skeletal system organization. Changes in neural or mesodermal tissue configuration arising from defects in the specification, patterning or relative axial placement of territories can severely compromise their integration and function. Here, we show that coordination of neural and mesodermal tissue at the zebrafish head-trunk transition crucially depends on two novel activities of the signaling factor retinoic acid (RA): one specifying the size and the other specifying the axial position relative to mesodermal structures of the hindbrain territory. These activities are each independent but coordinated with the well-established function of RA in hindbrain patterning. Using neural and mesodermal landmarks we demonstrate that the functions of RA in aligning neural and mesodermal tissues temporally precede the specification of hindbrain and spinal cord territories and the activation of hox transcription. Using cell transplantation assays we show that RA activity in the neuroepithelium regulates hindbrain patterning directly and territory size specification indirectly. This indirect function is partially dependent on Wnts but independent of FGFs. Importantly, RA specifies and patterns the hindbrain territory by antagonizing the activity of the spinal cord specification gene cdx4; loss of Cdx4 rescues the defects associated with the loss of RA, including the reduction in hindbrain size and the loss of posterior rhombomeres. We propose that at the head-trunk transition, RA coordinates specification, patterning and alignment of neural and mesodermal tissues that are essential for the organization and function of the neural and skeletal systems.
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Affiliation(s)
- Keun Lee
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA
| | - Isaac Skromne
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA
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27
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A Cdx4-Sall4 regulatory module controls the transition from mesoderm formation to embryonic hematopoiesis. Stem Cell Reports 2013; 1:425-36. [PMID: 24286030 PMCID: PMC3841246 DOI: 10.1016/j.stemcr.2013.10.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 10/01/2013] [Accepted: 10/02/2013] [Indexed: 12/26/2022] Open
Abstract
Deletion of caudal/cdx genes alters hox gene expression and causes defects in posterior tissues and hematopoiesis. Yet, the defects in hox gene expression only partially explain these phenotypes. To gain deeper insight into Cdx4 function, we performed chromatin immunoprecipitation sequencing (ChIP-seq) combined with gene-expression profiling in zebrafish, and identified the transcription factor spalt-like 4 (sall4) as a Cdx4 target. ChIP-seq revealed that Sall4 bound to its own gene locus and the cdx4 locus. Expression profiling showed that Cdx4 and Sall4 coregulate genes that initiate hematopoiesis, such as hox, scl, and lmo2. Combined cdx4/sall4 gene knockdown impaired erythropoiesis, and overexpression of the Cdx4 and Sall4 target genes scl and lmo2 together rescued the erythroid program. These findings suggest that auto- and cross-regulation of Cdx4 and Sall4 establish a stable molecular circuit in the mesoderm that facilitates the activation of the blood-specific program as development proceeds. Cdx4 and Sall4 bind to each other’s genomic loci Cdx4 and Sall4 coregulate genes responsible for the mesoderm-to-blood transition Scl and Lmo2 overexpression rescues blood defects in cdx4/sall4 double morphants
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28
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Mazzoni EO, Mahony S, Peljto M, Patel T, Thornton SR, McCuine S, Reeder C, Boyer LA, Young RA, Gifford DK, Wichterle H. Saltatory remodeling of Hox chromatin in response to rostrocaudal patterning signals. Nat Neurosci 2013; 16:1191-1198. [PMID: 23955559 PMCID: PMC3799941 DOI: 10.1038/nn.3490] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 07/10/2013] [Indexed: 12/16/2022]
Abstract
Hox genes controlling motor neuron subtype identity are expressed in rostro-caudal patterns that are spatially and temporally collinear with their chromosomal organization. Here we demonstrate that Hox chromatin is subdivided into discrete domains, controlled by rostro-caudal patterning signals that trigger rapid, domain-wide clearance of repressive H3K27me3 Polycomb modifications. Treatment of differentiating mouse neural progenitors with retinoic acid (RA) leads to activation and binding of RA receptors (RARs) to Hox1-5 chromatin domains, followed by a rapid domain-wide removal of H3K27me3 and acquisition of cervical spinal identity. Wnt and FGF signals induce expression of Cdx2 transcription factor that binds and clears H3K27me3 from Hox1-9 chromatin domains, leading to specification of brachial/thoracic spinal identity. We propose that rapid clearance of repressive modifications in response to transient patterning signals encodes global rostro-caudal neural identity and that maintenance of these chromatin domains ensures transmission of the positional identity to postmitotic motor neurons later in development.
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Affiliation(s)
- Esteban O Mazzoni
- Departments of Pathology and Cell Biology, Neurology, and Neuroscience, Center for Motor Neuron Biology and Disease, Columbia Stem Cell Initiative, Columbia University Medical Center, 630 W 168 Street, New York, NY 10032, USA.,Department of Biology, New York University. 100 Washington Square East, New York, NY 10003, USA
| | - Shaun Mahony
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, 32 Vassar Street, Cambridge, MA 02139, USA.,Department of Biochemistry & Molecular Biology, Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802
| | - Mirza Peljto
- Departments of Pathology and Cell Biology, Neurology, and Neuroscience, Center for Motor Neuron Biology and Disease, Columbia Stem Cell Initiative, Columbia University Medical Center, 630 W 168 Street, New York, NY 10032, USA
| | - Tulsi Patel
- Departments of Pathology and Cell Biology, Neurology, and Neuroscience, Center for Motor Neuron Biology and Disease, Columbia Stem Cell Initiative, Columbia University Medical Center, 630 W 168 Street, New York, NY 10032, USA
| | - Seraphim R Thornton
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Scott McCuine
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - Christopher Reeder
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, 32 Vassar Street, Cambridge, MA 02139, USA
| | - Laurie A Boyer
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Richard A Young
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - David K Gifford
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, 32 Vassar Street, Cambridge, MA 02139, USA
| | - Hynek Wichterle
- Departments of Pathology and Cell Biology, Neurology, and Neuroscience, Center for Motor Neuron Biology and Disease, Columbia Stem Cell Initiative, Columbia University Medical Center, 630 W 168 Street, New York, NY 10032, USA
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Abstract
The Wnt pathway is a major embryonic signaling pathway that controls cell proliferation, cell fate, and body-axis determination in vertebrate embryos. Soon after egg fertilization, Wnt pathway components play a role in microtubule-dependent dorsoventral axis specification. Later in embryogenesis, another conserved function of the pathway is to specify the anteroposterior axis. The dual role of Wnt signaling in Xenopus and zebrafish embryos is regulated at different developmental stages by distinct sets of Wnt target genes. This review highlights recent progress in the discrimination of different signaling branches and the identification of specific pathway targets during vertebrate axial development.
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Affiliation(s)
- Hiroki Hikasa
- Division of Cancer Genetics, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan
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30
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Gerlach GF, Wingert RA. Kidney organogenesis in the zebrafish: insights into vertebrate nephrogenesis and regeneration. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2012; 2:559-85. [PMID: 24014448 DOI: 10.1002/wdev.92] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Vertebrates form a progressive series of up to three kidney organs during development-the pronephros, mesonephros, and metanephros. Each kidney derives from the intermediate mesoderm and is comprised of conserved excretory units called nephrons. The zebrafish is a powerful model for vertebrate developmental genetics, and recent studies have illustrated that zebrafish and mammals share numerous similarities in nephron composition and physiology. The zebrafish embryo forms an architecturally simple pronephros that has two nephrons, and these eventually become a scaffold onto which a mesonephros of several hundred nephrons is constructed during larval stages. In adult zebrafish, the mesonephros exhibits ongoing nephrogenesis, generating new nephrons from a local pool of renal progenitors during periods of growth or following kidney injury. The characteristics of the zebrafish pronephros and mesonephros make them genetically tractable kidney systems in which to study the functions of renal genes and address outstanding questions about the mechanisms of nephrogenesis. Here, we provide an overview of the formation and composition of these zebrafish kidney organs, and discuss how various zebrafish mutants, gene knockdowns, and transgenic models have created frameworks in which to further delineate nephrogenesis pathways.
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Affiliation(s)
- Gary F Gerlach
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
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31
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Sanchez-Ferras O, Coutaud B, Djavanbakht Samani T, Tremblay I, Souchkova O, Pilon N. Caudal-related homeobox (Cdx) protein-dependent integration of canonical Wnt signaling on paired-box 3 (Pax3) neural crest enhancer. J Biol Chem 2012; 287:16623-35. [PMID: 22457346 DOI: 10.1074/jbc.m112.356394] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
One of the earliest events in neural crest development takes place at the neural plate border and consists in the induction of Pax3 expression by posteriorizing Wnt·β-catenin signaling. The molecular mechanism of this regulation is not well understood, but several observations suggest a role for posteriorizing Cdx transcription factors (Cdx1/2/4) in this process. Cdx genes are known as integrators of posteriorizing signals from Wnt, retinoic acid, and FGF pathways. In this work, we report that Wnt-mediated regulation of murine Pax3 expression is indirect and involves Cdx proteins as intermediates. We show that Pax3 transcripts co-localize with Cdx proteins in the posterior neurectoderm and that neural Pax3 expression is reduced in Cdx1-null embryos. Using Wnt3a-treated P19 cells and neural crest-derived Neuro2a cells, we demonstrate that Pax3 expression is induced by the Wnt-Cdx pathway. Co-transfection analyses, electrophoretic mobility shift assays, chromatin immunoprecipitation, and transgenic studies further indicate that Cdx proteins operate via direct binding to an evolutionarily conserved neural crest enhancer of the Pax3 proximal promoter. Taken together, these results suggest a novel neural function for Cdx proteins within the gene regulatory network controlling neural crest development.
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Affiliation(s)
- Oraly Sanchez-Ferras
- Molecular Genetics of Development, Department of Biological Sciences, and BioMed Research Center, Faculty of Sciences, University of Quebec, Montreal, Quebec H2X 3Y7, Canada
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32
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Doodnath R, Wride M, Puri P. The spatio-temporal patterning of Hoxa9 and Hoxa13 in the developing zebrafish enteric nervous system. Pediatr Surg Int 2012; 28:115-21. [PMID: 21971947 DOI: 10.1007/s00383-011-2992-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Hirschsprung's disease is characterised by the absence of ganglion cells in the distal bowel, a process which is controlled by complex genetic pathways. Homeobox genes have a major role in gut development and this is depicted by the enteric Hox code which describes the different spatial and temporal expression of Hox genes. Hoxa9 and Hoxa13 mutations have been discovered in patients with Hirschsprung's disease (HD). The aim of this study was to determine the spatio-temporal pattern of Hoxa9 and Hoxa13 in enteric nervous system (ENS) development using the zebrafish model. METHODS Purified plasmids that contained the gene of interest were obtained and inoculated into culture medium to exponentially increase the number of bacteria containing the plasmid. Cells were then harvested by centrifugation and plasmid DNA was extracted, which was then linearised and precipitated. RNA digoxigenin-labelled probes were made by in vitro transcription reaction. In situ hybridisation was carried out using these probes on zebrafish embryos which were collected from 24 to 120 h post fertilisation (hpf), by which time the zebrafish intestine is fully developed. Embryos were then mounted in glycerol and imaged using an Olympus B40 microscope and images were taken using an Olympus Super F1.8 digital camera. RESULTS At 24 hpf, Hoxa9 expression is seen in the forebrain and hindbrain and also in the very distal myotome whereas Hoxa13 expression, however, is seen only at the forebrain and hindbrain. At 48 hpf, Hoxa9- and Hoxa13-labelled cells are seen migrating distally from the forebrain into the notochord and spinal cord. At 72 hpf, Hoxa9-labelled cells can be seen throughout the spinal cord whereas Hoxa13 positive cells are seen migrating down from the spinal cord and in the proximal gut. By 96 hpf, Hoxa9- and Hoxa13-labelled cells have migrated down the full length of the spinal cord and along the proximal and mid intestine. By 120 hpf, Hoxa9 and Hoxa13 positive cells can be seen along the entire length of the zebrafish intestine. CONCLUSIONS These results show further evidence that Hoxa9 and Hoxa13 are involved in the early and organised patterning of ENS development in the zebrafish model.
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Affiliation(s)
- R Doodnath
- National Children's Research Centre, Our Lady's Children's Hospital, Crumlin, Dublin 12, Ireland
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33
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Ikuta T. Evolution of invertebrate deuterostomes and Hox/ParaHox genes. GENOMICS, PROTEOMICS & BIOINFORMATICS 2011; 9:77-96. [PMID: 21802045 PMCID: PMC5054439 DOI: 10.1016/s1672-0229(11)60011-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Accepted: 03/21/2011] [Indexed: 11/10/2022]
Abstract
Transcription factors encoded by Antennapedia-class homeobox genes play crucial roles in controlling development of animals, and are often found clustered in animal genomes. The Hox and ParaHox gene clusters have been regarded as evolutionary sisters and evolved from a putative common ancestral gene complex, the ProtoHox cluster, prior to the divergence of the Cnidaria and Bilateria (bilaterally symmetrical animals). The Deuterostomia is a monophyletic group of animals that belongs to the Bilateria, and a sister group to the Protostomia. The deuterostomes include the vertebrates (to which we belong), invertebrate chordates, hemichordates, echinoderms and possibly xenoturbellids, as well as acoelomorphs. The studies of Hox and ParaHox genes provide insights into the origin and subsequent evolution of the bilaterian animals. Recently, it becomes apparent that among the Hox and ParaHox genes, there are significant variations in organization on the chromosome, expression pattern, and function. In this review, focusing on invertebrate deuterostomes, I first summarize recent findings about Hox and ParaHox genes. Next, citing unsolved issues, I try to provide clues that might allow us to reconstruct the common ancestor of deuterostomes, as well as understand the roles of Hox and ParaHox genes in the development and evolution of deuterostomes.
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Affiliation(s)
- Tetsuro Ikuta
- Marine Genomics Unit, Okinawa Institute of Science and Technology, Uruma, Japan.
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34
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Lengerke C, Wingert R, Beeretz M, Grauer M, Schmidt AG, Konantz M, Daley GQ, Davidson AJ. Interactions between Cdx genes and retinoic acid modulate early cardiogenesis. Dev Biol 2011; 354:134-42. [PMID: 21466798 DOI: 10.1016/j.ydbio.2011.03.027] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Revised: 03/01/2011] [Accepted: 03/28/2011] [Indexed: 02/04/2023]
Abstract
Cdx transcription factors regulate embryonic positional identities and have crucial roles in anteroposterior patterning (AP) processes of all three germ layers. Previously we have shown that the zebrafish homologues cdx1a and cdx4 redundantly regulate posterior mesodermal derivatives inducing embryonic blood cell fate specification and patterning of the embryonic kidney. Here we hypothesize that cdx factors restrict formation of anterior mesodermal derivatives such as cardiac cells by imposing posterior identity to developing mesodermal cells. We show that ectopic expression of Cdx1 or Cdx4 applied during the brief window of mesoderm patterning in differentiating murine embryonic stem cell (ESC) strongly suppresses cardiac development as assayed by expression of cardiac genes and formation of embryoid bodies (EB) containing "beating" cell clusters. Conversely, in loss-of-function studies performed in cdx-deficient zebrafish embryos, we observed a dose-dependent expansion of tbx5a(+) anterior-lateral plate mesoderm giving rise to cardiac progenitors. However, further cardiac development of these mesodermal cells required additional suppression of the retinoic acid (RA) pathway, possibly due to differential activity of inhibitory RA signals in cdx mutants. Together, our data suggest that cdx proteins affect cardiogenesis by regulating the formation of cardiogenic mesoderm and together with the RA pathway control the early development of cardiac precursor cells.
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Affiliation(s)
- Claudia Lengerke
- Department of Hematology and Oncology, University of Tuebingen Medical Center II, Tuebingen, Germany.
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35
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Peters A, Burridge PW, Pryzhkova MV, Levine MA, Park TS, Roxbury C, Yuan X, Péault B, Zambidis ET. Challenges and strategies for generating therapeutic patient-specific hemangioblasts and hematopoietic stem cells from human pluripotent stem cells. THE INTERNATIONAL JOURNAL OF DEVELOPMENTAL BIOLOGY 2011; 54:965-90. [PMID: 20563986 DOI: 10.1387/ijdb.093043ap] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Recent characterization of hemangioblasts differentiated from human embryonic stem cells (hESC) has further confirmed evidence from murine, zebrafish and avian experimental systems that hematopoietic and endothelial lineages arise from a common progenitor. Such progenitors may provide a valuable resource for delineating the initial developmental steps of human hemato-endotheliogenesis, which is a process normally difficult to study due to the very limited accessibility of early human embryonic/fetal tissues. Moreover, efficient hemangioblast and hematopoietic stem cell (HSC) generation from patient-specific pluripotent stem cells has enormous potential for regenerative medicine, since it could lead to strategies for treating a multitude of hematologic and vascular disorders. However, significant scientific challenges remain in achieving these goals, and the generation of transplantable hemangioblasts and HSC derived from hESC currently remains elusive. Our previous work has suggested that the failure to derive engraftable HSC from hESC is due to the fact that current methodologies for differentiating hESC produce hematopoietic progenitors developmentally similar to those found in the human yolk sac, and are therefore too immature to provide adult-type hematopoietic reconstitution. Herein, we outline the nature of this challenge and propose targeted strategies for generating engraftable human pluripotent stem cell-derived HSC from primitive hemangioblasts using a developmental approach. We also focus on methods by which reprogrammed somatic cells could be used to derive autologous pluripotent stem cells, which in turn could provide unlimited sources of patient-specific hemangioblasts and HSC.
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Affiliation(s)
- Ann Peters
- Institute for Cell Engineering, Stem Cell Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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36
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Wheadon H, Ramsey JM, Dobbin E, Dickson GJ, Corrigan PM, Freeburn RW, Thompson A. Differential Hox expression in murine embryonic stem cell models of normal and malignant hematopoiesis. Stem Cells Dev 2011; 20:1465-76. [PMID: 21083428 DOI: 10.1089/scd.2010.0226] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The Hox family are master transcriptional regulators of developmental processes, including hematopoiesis. The Hox regulators, caudal homeobox factors (Cdx1-4), and Meis1, along with several individual Hox proteins, are implicated in stem cell expansion during embryonic development, with gene dosage playing a significant role in the overall function of the integrated Hox network. To investigate the role of this network in normal and aberrant, early hematopoiesis, we employed an in vitro embryonic stem cell differentiation system, which recapitulates mouse developmental hematopoiesis. Expression profiles of Hox, Pbx1, and Meis1 genes were quantified at distinct stages during the hematopoietic differentiation process and compared with the effects of expressing the leukemic oncogene Tel/PDGFRβ. During normal differentiation the Hoxa cluster, Pbx1 and Meis1 predominated, with a marked reduction in the majority of Hox genes (27/39) and Meis1 occurring during hematopoietic commitment. Only the posterior Hoxa cluster genes (a9, a10, a11, and a13) maintained or increased expression at the hematopoietic colony stage. Cdx4, Meis1, and a subset of Hox genes, including a7 and a9, were differentially expressed after short-term oncogenic (Tel/PDGFRβ) induction. Whereas Hoxa4-10, b1, b2, b4, and b9 were upregulated during oncogenic driven myelomonocytic differentiation. Heterodimers between Hoxa7/Hoxa9, Meis1, and Pbx have previously been implicated in regulating target genes involved in hematopoietic stem cell (HSC) expansion and leukemic progression. These results provide direct evidence that transcriptional flux through the Hox network occurs at very early stages during hematopoietic differentiation and validates embryonic stem cell models for gaining insights into the genetic regulation of normal and malignant hematopoiesis.
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Affiliation(s)
- Helen Wheadon
- Paul O'Gorman Leukaemia Research Centre, University of Glasgow, Glasgow, United Kingdom
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37
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Sturgeon K, Kaneko T, Biemann M, Gauthier A, Chawengsaksophak K, Cordes SP. Cdx1 refines positional identity of the vertebrate hindbrain by directly repressing Mafb expression. Development 2010; 138:65-74. [PMID: 21098558 DOI: 10.1242/dev.058727] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
An interplay of transcription factors interprets signalling pathways to define anteroposterior positions along the vertebrate axis. In the hindbrain, these transcription factors prompt the position-appropriate appearance of seven to eight segmental structures, known as rhombomeres (r1-r8). The evolutionarily conserved Cdx caudal-type homeodomain transcription factors help specify the vertebrate trunk and tail but have not been shown to directly regulate hindbrain patterning genes. Mafb (Kreisler, Krml1, valentino), a basic domain leucine zipper transcription factor, is required for development of r5 and r6 and is the first gene to show restricted expression within these two segments. The homeodomain protein vHnf1 (Hnf1b) directly activates Mafb expression. vHnf1 and Mafb share an anterior expression limit at the r4/r5 boundary but vHnf1 expression extends beyond the posterior limit of Mafb and, therefore, cannot establish the posterior Mafb expression boundary. Upon identifying regulatory sequences responsible for posterior Mafb repression, we have used in situ hybridization, immunofluorescence and chromatin immunoprecipitation (ChIP) analyses to determine that Cdx1 directly inhibits early Mafb expression in the neural tube posterior of the r6/r7 boundary, which is the anteriormost boundary of Cdx1 expression in the hindbrain. Cdx1 dependent repression of Mafb is transient. After the 10-somite stage, another mechanism acts to restrict Mafb expression in its normal r5 and r6 domain, even in the absence of Cdx1. Our findings identify Mafb as one of the earliest direct targets of Cdx1 and show that Cdx1 plays a direct role in early hindbrain patterning. Thus, just as Cdx2 and Cdx4 govern the trunk-to-tail transition, Cdx1 may regulate the hindbrain-to-spinal cord transition.
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Affiliation(s)
- Kendra Sturgeon
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada
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38
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Boyd M, Hansen M, Jensen TGK, Perearnau A, Olsen AK, Bram LL, Bak M, Tommerup N, Olsen J, Troelsen JT. Genome-wide analysis of CDX2 binding in intestinal epithelial cells (Caco-2). J Biol Chem 2010; 285:25115-25. [PMID: 20551321 DOI: 10.1074/jbc.m109.089516] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The CDX2 transcription factor is known to play a crucial role in inhibiting proliferation, promoting differentiation and the expression of intestinal specific genes in intestinal cells. The overall effect of CDX2 in intestinal cells has previously been investigated in conditional knock-out mice, revealing a critical role of CDX2 in the formation of the normal intestinal identity. The identification of direct targets of transcription factors is a key problem in the study of gene regulatory networks. The ChIP-seq technique combines chromatin immunoprecipitation (ChIP) with next generation sequencing resulting in a high throughput experimental method of identifying direct targets of specific transcription factors. The method was applied to CDX2, leading to the identification of the direct binding of CDX2 to several known and novel target genes in the intestinal cell. Examination of the transcript levels of selected genes verified the regulatory role of CDX2 binding. The results place CDX2 as a key node in a transcription factor network controlling the proliferation and differentiation of intestinal cells.
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Affiliation(s)
- Mette Boyd
- Department of Cellular and Molecular Medicine, Panum Institute, Building 6.4, University of Copenhagen, Blegdamsvej 3. 2200 Copenhagen N, Denmark
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39
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Pedrosa E, Kaushik S, Lachman HM. ChIP-chip analysis of neurexins and other candidate genes for addiction and neuropsychiatric disorders. J Neurogenet 2010; 24:5-17. [PMID: 19968605 DOI: 10.3109/01677060903305658] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Several addiction susceptibility genes have been mapped by linkage and genomewide association. However, functional alleles associated with disease risk have not been identified, with a few possible exceptions. In addition, little is known about the cis- and trans-acting factors involved in regulating their expression. To address these issues, we used a ChIP-chip approach to identify regulatory elements in fetal-brain- targeting genes implicated in addiction and other neuropsychiatric conditions. Our data point to a number of putative regulatory elements, several of which, we show, are functionally significant. Many established or putative regulatory elements map near-disease-associated SNPs. These regions would be of interest to survey for patient-specific functional variants involved in disease susceptibility.
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Affiliation(s)
- Erika Pedrosa
- Department of Psychiatry and Behavioral Sciences, Division of Basic Research, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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40
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Abstract
Hematopoietic development during embryogenesis involves the interaction of extrinsic signaling pathways coupled to an intrinsic cell fate that is regulated by cell-specific transcription factors. Retinoic acid (RA) has been linked to stem cell self-renewal in adults and also participates in yolk sac blood island formation. Here, we demonstrate that RA decreases gata1 expression and blocks primitive hematopoiesis in zebrafish (Danio rerio) embryos, while increasing expression of the vascular marker, fli1. Treatment with an inhibitor of RA biosynthesis or a retinoic acid receptor antagonist increases gata1(+) erythroid progenitors in the posterior mesoderm of wild-type embryos and anemic cdx4(-/-) mutants, indicating a link between the cdx-hox signaling pathway and RA. Overexpression of scl, a DNA binding protein necessary for hematopoietic development, rescues the block of hematopoiesis induced by RA. We show that these effects of RA and RA pathway inhibitors are conserved during primitive hematopoiesis in murine yolk sac explant cultures and embryonic stem cell assays. Taken together, these data indicate that RA inhibits the commitment of mesodermal cells to hematopoietic fates, functioning downstream of cdx4 and upstream of scl. Our studies establish a new connection between RA and scl during development that may participate in stem cell self-renewal and hematopoietic differentiation.
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41
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Induction and patterning of trunk and tail neural ectoderm by the homeobox gene eve1 in zebrafish embryos. Proc Natl Acad Sci U S A 2010; 107:3564-9. [PMID: 20142486 DOI: 10.1073/pnas.1000389107] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In vertebrates, Evx homeodomain transcription factor-encoding genes are expressed in the posterior region during embryonic development, and overexpression experiments have revealed roles in tail development in fish and frogs. We analyzed the molecular mechanisms of posterior neural development and axis formation regulated by eve1. We show that eve1 is involved in establishing trunk and tail neural ectoderm by two independent mechanisms: First, eve1 posteriorizes neural ectoderm via induction of aldh1a2, which encodes an enzyme that synthesizes retinoic acid; second, eve1 is involved in neural induction in the posterior ectoderm by attenuating BMP expression. Further, eve1 can restore trunk neural tube formation in the organizer-deficient ichabod(-/-) mutant. We conclude that eve1 is crucial for the organization of the antero-posterior and dorso-ventral axis in the gastrula ectoderm and also has trunk- and tail-promoting activity.
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42
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Abstract
The endoderm germ layer contributes to the respiratory and gastrointestinal tracts and to all of their associated organs. Over the past decade, studies in vertebrate model organisms, including frog, fish, chick, and mouse, have greatly enhanced our understanding of the molecular basis of endoderm organ development. We review this progress with a focus on early stages of endoderm organogenesis including endoderm formation, gut tube morphogenesis and patterning, and organ specification. Lastly, we discuss how developmental mechanisms that regulate endoderm organogenesis are used to direct differentiation of embryonic stem cells into specific adult cell types, which function to alleviate disease symptoms in animal models.
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Affiliation(s)
- Aaron M Zorn
- Division of Developmental Biology, Cincinnati Children's Research Foundation and Department of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, Ohio 45229, USA.
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43
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44
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45
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Research progress of zebrafish as a model system for hematological neoplasms. YI CHUAN = HEREDITAS 2009; 31:889-95. [DOI: 10.3724/sp.j.1005.2009.00889] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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46
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Model organisms inform the search for the genes and developmental pathology underlying malformations of the human hindbrain. Semin Pediatr Neurol 2009; 16:155-63. [PMID: 19778712 PMCID: PMC2778478 DOI: 10.1016/j.spen.2009.06.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Congenital malformations of the human hindbrain, including the cerebellum, are poorly understood largely because their recognition is a relatively recent advance for imaging diagnostics. Cerebellar malformations are the most obvious and best characterized hindbrain malformations due to their relative ease of viewing by magnetic resonance imaging and the recent identification of several causative genes (Millen et al. Curr Opin Neurobiol 18:12-19, 2008). Malformations of the pons and medulla have also been described both in isolation and in association with cerebellar malformations (Barkovich et al. Ann Neurol 62:625-639, 2007). Although little is understood regarding the specific developmental pathologies underlying hindbrain malformations in humans, much is known regarding the mechanisms and genes driving hindbrain development in vertebrate model organisms. Thus, studies in vertebrate models provide a developmental framework in which to categorize human hindbrain malformations and serve to provide information regarding disrupted developmental processes and candidate genes. Here, we survey the basic principles of vertebrate hindbrain development and integrate our current knowledge of human hindbrain malformations into this framework.
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47
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Waxman JS, Yelon D. Increased Hox activity mimics the teratogenic effects of excess retinoic acid signaling. Dev Dyn 2009; 238:1207-13. [PMID: 19384962 DOI: 10.1002/dvdy.21951] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Excess retinoic acid (RA) signaling can be teratogenic and result in cardiac birth defects, but the cellular and molecular origins of these defects are not well understood. Excessive RA signaling can completely eliminate heart formation in the zebrafish embryo. However, atrial and ventricular cells are differentially sensitive to more modest increases in RA signaling. Increased Hox activity, downstream of RA signaling, causes phenotypes similar to those resulting from excess RA. These results suggest that Hox activity mediates the differential effects of ectopic RA on atrial and ventricular cardiomyocytes and may underlie the teratogenic effects of RA on the heart.
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Affiliation(s)
- Joshua S Waxman
- Developmental Genetics Program and Department of Cell Biology, Kimmel Center for Biology and Medicine at the Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, New York 10016, USA
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48
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Roche DD, Liu KJ, Harland RM, Monsoro-Burq AH. Dazap2 is required for FGF-mediated posterior neural patterning, independent of Wnt and Cdx function. Dev Biol 2009; 333:26-36. [PMID: 19555680 DOI: 10.1016/j.ydbio.2009.06.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2009] [Revised: 05/19/2009] [Accepted: 06/15/2009] [Indexed: 01/15/2023]
Abstract
The organization of the embryonic neural plate requires coordination of multiple signal transduction pathways, including fibroblast growth factors (FGFs), bone morphogenetic proteins (BMPs), and WNTs. Many studies have suggested that a critical component of this process is the patterning of posterior neural tissues by an FGF-caudal signaling cascade. Here, we have identified a novel player, Dazap2, and show that it is required in vivo for posterior neural fate. Loss of Dazap2 in embryos resulted in diminished expression of hoxb9 with a concurrent increase in the anterior marker otx2. Furthermore, we found that Dazap2 is required for FGF dependent posterior patterning; surprisingly, this is independent of Cdx activity. Furthermore, in contrast to FGF activity, Dazap2 induction of hoxb9 is not blocked by loss of canonical Wnt signaling. Functionally, we found that increasing Dazap2 levels alters neural patterning and induces posterior neural markers. This activity overcomes the anteriorizing effects of noggin, and is downstream of FGF receptor activation. Our results strongly suggest that Dazap2 is a novel and essential branch of FGF-induced neural patterning.
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Affiliation(s)
- Daniel D Roche
- Institut Curie, CNRS, UMR146, Centre Universitaire, Batiment 110, 91405 Orsay Cedex, France
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Establishment of intestinal identity and epithelial-mesenchymal signaling by Cdx2. Dev Cell 2009; 16:588-99. [PMID: 19386267 DOI: 10.1016/j.devcel.2009.02.010] [Citation(s) in RCA: 289] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Revised: 12/16/2008] [Accepted: 02/18/2009] [Indexed: 12/22/2022]
Abstract
We demonstrate that conditional ablation of the homeobox transcription factor Cdx2 from early endoderm results in the replacement of the posterior intestinal epithelium with keratinocytes, a dramatic cell fate conversion caused by ectopic activation of the foregut/esophageal differentiation program. This anterior homeotic transformation of the intestine was first apparent in the early embryonic Cdx2-deficient gut by a caudal extension of the expression domains of several key foregut endoderm regulators. While the intestinal transcriptome was severely affected, Cdx2 deficiency only transiently modified selected posterior Hox genes and the primary enteric Hox code was maintained. Further, we demonstrate that Cdx2-directed intestinal cell fate adoption plays an important role in the establishment of normal epithelial-mesenchymal interactions, as multiple signaling pathways involved in this process were severely affected. We conclude that Cdx2 controls important aspects of intestinal identity and development, and that this function is largely independent of the enteric Hox code.
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Cyp26 enzymes function in endoderm to regulate pancreatic field size. Proc Natl Acad Sci U S A 2009; 106:7864-9. [PMID: 19416885 DOI: 10.1073/pnas.0813108106] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The control of organ size and position relies, at least in part, upon appropriate regulation of the signals that specify organ progenitor fields. Pancreatic cell fates are specified by retinoic acid (RA), and proper size and localization of the pancreatic field are dependent on tight control of RA signaling. Here we show that the RA-degrading Cyp26 enzymes play a critical role in defining the normal anterior limit of the pancreatic field. Disruption of Cyp26 function causes a dramatic expansion of pancreatic cell types toward the anterior of the embryo. The cyp26a1 gene is expressed in the anterior trunk endoderm at developmental stages when RA is signaling to specify pancreas, and analysis of cyp26a1/giraffe (gir) mutant zebrafish embryos confirms that cyp26a1 plays the primary role in setting the anterior limit of the pancreas. Analysis of the gir mutants further reveals that cyp26b1 and cyp26c1 function redundantly to partially compensate for loss of Cyp26a1 function. We used cell transplantation to determine that Cyp26a1 functions directly in endoderm to modulate RA signaling and limit the pancreatic field. Taken together with our finding that endodermal expression of cyp26 genes is subject to positive regulation by RA, our data reveal a feedback loop within the endoderm. Such feedback can maintain consistent levels of RA signaling, despite environmental fluctuations in RA concentration, thus ensuring a consistent size and location of the pancreatic field.
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