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Asashima M, Satou-Kobayashi Y. Spemann-Mangold organizer and mesoderm induction. Cells Dev 2024; 178:203903. [PMID: 38295873 DOI: 10.1016/j.cdev.2024.203903] [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] [Received: 11/13/2023] [Revised: 01/23/2024] [Accepted: 01/24/2024] [Indexed: 02/09/2024]
Abstract
The discovery of the Spemann-Mangold organizer strongly influenced subsequent research on embryonic induction, with research aiming to elucidate the molecular characteristics of organizer activity being currently underway. Herein, we review the history of research on embryonic induction, and describe how the mechanisms of induction phenomena and developmental processes have been investigated. Classical experiments investigating the differentiation capacity and inductive activity of various embryonic regions were conducted by many researchers, and important theories of region-specific induction and the concept for chain of induction were proposed. The transition from experimental embryology to developmental biology has enabled us to understand the mechanisms of embryonic induction at the molecular level. Consequently, many inducing substances and molecules such as transcriptional factors and peptide growth factors involved in the organizer formation were identified. One of peptide growth factors, activin, acts as a mesoderm- and endoderm-inducing substance. Activin induces several tissues and organs from the undifferentiated cell mass of amphibian embryos in a concentration-dependent manner. We review the extent to which we can control in vitro organogenesis from undifferentiated cells, and discuss the application to stem cell-based regenerative medicine based on insights gained from animal experiments, such as in amphibians.
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Affiliation(s)
- Makoto Asashima
- Advanced Comprehensive Research Organization, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-0003, Japan.
| | - Yumeko Satou-Kobayashi
- Advanced Comprehensive Research Organization, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-0003, Japan
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2
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Manning E, Placzek M. Organizing activities of axial mesoderm. Curr Top Dev Biol 2024; 157:83-123. [PMID: 38556460 DOI: 10.1016/bs.ctdb.2024.02.007] [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: 04/02/2024]
Abstract
For almost a century, developmental biologists have appreciated that the ability of the embryonic organizer to induce and pattern the body plan is intertwined with its differentiation into axial mesoderm. Despite this, we still have a relatively poor understanding of the contribution of axial mesoderm to induction and patterning of different body regions, and the manner in which axial mesoderm-derived information is interpreted in tissues of changing competence. Here, with a particular focus on the nervous system, we review the evidence that axial mesoderm notochord and prechordal mesoderm/mesendoderm act as organizers, discuss how their influence extends through the different axes of the developing organism, and describe how the ability of axial mesoderm to direct morphogenesis impacts on its role as a local organizer.
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Affiliation(s)
- Elizabeth Manning
- School of Biosciences, University of Sheffield, Sheffield, United Kingdom; Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Marysia Placzek
- School of Biosciences, University of Sheffield, Sheffield, United Kingdom; Bateson Centre, University of Sheffield, Sheffield, United Kingdom; Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom.
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3
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Keum BR, Yeo I, Koo Y, Han W, Choi SC, Kim GH, Han JK. Transmembrane protein 150b attenuates BMP signaling in the Xenopus organizer. J Cell Physiol 2023; 238:1850-1866. [PMID: 37435758 DOI: 10.1002/jcp.31059] [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] [Received: 10/27/2022] [Revised: 05/03/2023] [Accepted: 05/06/2023] [Indexed: 07/13/2023]
Abstract
The vertebrate organizer is a specified embryonic tissue that regulates dorsoventral patterning and axis formation. Although numerous cellular signaling pathways have been identified as regulators of the organizer's dynamic functions, the process remains incompletely understood, and as-yet unknown pathways remain to be explored for sophisticated mechanistic understanding of the vertebrate organizer. To identify new potential key factors of the organizer, we performed complementary DNA (cDNA) microarray screening using organizer-mimicking Xenopus laevis tissue. This analysis yielded a list of prospective organizer genes, and we determined the role of six-transmembrane domain containing transmembrane protein 150b (Tmem150b) in organizer function. Tmem150b was expressed in the organizer region and induced by Activin/Nodal signaling. In X. laevis, Tmem150b knockdown resulted in head defects and a shortened body axis. Moreover, Tmem150b negatively regulated bone morphogenetic protein (BMP) signaling, likely via physical interaction with activin receptor-like kinase 2 (ALK2). These findings demonstrated that Tmem150b functions as a novel membrane regulatory factor of BMP signaling with antagonistic effects, contributing to the understanding of regulatory molecular mechanisms of organizer axis function. Investigation of additional candidate genes identified in the cDNA microarray analysis could further delineate the genetic networks of the organizer during vertebrate embryogenesis.
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Affiliation(s)
- Byeong-Rak Keum
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk, Korea
- Research Center for drug development, CYPHARMA, Daejeon, Korea
| | - Inchul Yeo
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk, Korea
| | - Youngmu Koo
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk, Korea
| | - Wonhee Han
- Department of Neurology, F. M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Sun-Cheol Choi
- Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, Korea
| | - Gun-Hwa Kim
- Research Center for drug development, CYPHARMA, Daejeon, Korea
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Cheongju, Korea
| | - Jin-Kwan Han
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk, Korea
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4
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Computational approaches to understand transcription regulation in development. Biochem Soc Trans 2023; 51:1-12. [PMID: 36695505 PMCID: PMC9988001 DOI: 10.1042/bst20210145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 01/07/2023] [Accepted: 01/13/2023] [Indexed: 01/26/2023]
Abstract
Gene regulatory networks (GRNs) serve as useful abstractions to understand transcriptional dynamics in developmental systems. Computational prediction of GRNs has been successfully applied to genome-wide gene expression measurements with the advent of microarrays and RNA-sequencing. However, these inferred networks are inaccurate and mostly based on correlative rather than causative interactions. In this review, we highlight three approaches that significantly impact GRN inference: (1) moving from one genome-wide functional modality, gene expression, to multi-omics, (2) single cell sequencing, to measure cell type-specific signals and predict context-specific GRNs, and (3) neural networks as flexible models. Together, these experimental and computational developments have the potential to significantly impact the quality of inferred GRNs. Ultimately, accurately modeling the regulatory interactions between transcription factors and their target genes will be essential to understand the role of transcription factors in driving developmental gene expression programs and to derive testable hypotheses for validation.
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5
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Durant-Vesga J, Suzuki N, Ochi H, Le Bouffant R, Eschstruth A, Ogino H, Umbhauer M, Riou JF. Retinoic acid control of pax8 during renal specification of Xenopus pronephros involves hox and meis3. Dev Biol 2023; 493:17-28. [PMID: 36279927 DOI: 10.1016/j.ydbio.2022.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 10/12/2022] [Accepted: 10/13/2022] [Indexed: 11/16/2022]
Abstract
Development of the Xenopus pronephros relies on renal precursors grouped at neurula stage into a specific region of dorso-lateral mesoderm called the kidney field. Formation of the kidney field at early neurula stage is dependent on retinoic (RA) signaling acting upstream of renal master transcriptional regulators such as pax8 or lhx1. Although lhx1 might be a direct target of RA-mediated transcriptional activation in the kidney field, how RA controls the emergence of the kidney field remains poorly understood. In order to better understand RA control of renal specification of the kidney field, we have performed a transcriptomic profiling of genes affected by RA disruption in lateral mesoderm explants isolated prior to the emergence of the kidney field and cultured at different time points until early neurula stage. Besides genes directly involved in pronephric development (pax8, lhx1, osr2, mecom), hox (hoxa1, a3, b3, b4, c5 and d1) and the hox co-factor meis3 appear as a prominent group of genes encoding transcription factors (TFs) downstream of RA. Supporting the idea of a role of meis3 in the kidney field, we have observed that meis3 depletion results in a severe inhibition of pax8 expression in the kidney field. Meis3 depletion only marginally affects expression of lhx1 and aldh1a2 suggesting that meis3 principally acts upstream of pax8. Further arguing for a role of meis3 and hox in the control of pax8, expression of a combination of meis3, hoxb4 and pbx1 in animal caps induces pax8 expression, but not that of lhx1. The same combination of TFs is also able to transactivate a previously identified pax8 enhancer, Pax8-CNS1. Mutagenesis of potential PBX-Hox binding motifs present in Pax8-CNS1 further allows to identify two of them that are necessary for transactivation. Finally, we have tested deletions of regulatory sequences in reporter assays with a previously characterized transgene encompassing 36.5 kb of the X. tropicalis pax8 gene that allows expression of a truncated pax8-GFP fusion protein recapitulating endogenous pax8 expression. This transgene includes three conserved pax8 enhancers, Pax8-CNS1, Pax8-CNS2 and Pax8-CNS3. Deletion of Pax8-CNS1 alone does not affect reporter expression, but deletion of a 3.5 kb region encompassing Pax8-CNS1 and Pax8-CNS2 results in a severe inhibition of reporter expression both in the otic placode and kidney field domains.
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Affiliation(s)
- Jennifer Durant-Vesga
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, IBPS, Laboratoire de Biologie Du Développement, UMR7622, 9, Quai Saint-Bernard, 75252, Paris, Cedex05, France
| | - Nanoka Suzuki
- Institute for Promotion of Medical Science Research, Faculty of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata, 990-9585, Japan; Amphibian Research Center / Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagami-yama, Higashi-Hiroshima, Hiroshima, 739-8526, Japan
| | - Haruki Ochi
- Institute for Promotion of Medical Science Research, Faculty of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata, 990-9585, Japan
| | - Ronan Le Bouffant
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, IBPS, Laboratoire de Biologie Du Développement, UMR7622, 9, Quai Saint-Bernard, 75252, Paris, Cedex05, France
| | - Alexis Eschstruth
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, IBPS, Laboratoire de Biologie Du Développement, UMR7622, 9, Quai Saint-Bernard, 75252, Paris, Cedex05, France
| | - Hajime Ogino
- Amphibian Research Center / Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagami-yama, Higashi-Hiroshima, Hiroshima, 739-8526, Japan
| | - Muriel Umbhauer
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, IBPS, Laboratoire de Biologie Du Développement, UMR7622, 9, Quai Saint-Bernard, 75252, Paris, Cedex05, France
| | - Jean-François Riou
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, IBPS, Laboratoire de Biologie Du Développement, UMR7622, 9, Quai Saint-Bernard, 75252, Paris, Cedex05, France.
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6
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Favarolo MB, Revinski DR, Garavaglia MJ, López SL. Nodal and churchill1 position the expression of a notch ligand during Xenopus germ layer segregation. Life Sci Alliance 2022; 5:5/12/e202201693. [PMID: 36180230 PMCID: PMC9604498 DOI: 10.26508/lsa.202201693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 11/24/2022] Open
Abstract
Churchill and Nodal signaling, which participate in vertebrates’ germ layer induction, position a domain of Delta/Notch activity, which refines germ layer boundaries during frog gastrulation. In vertebrates, Nodal signaling plays a major role in endomesoderm induction, but germ layer delimitation is poorly understood. In avian embryos, the neural/mesoderm boundary is controlled by the transcription factor CHURCHILL1, presumably through the repressor ZEB2, but there is scarce knowledge about its role in other vertebrates. During amphibian gastrulation, Delta/Notch signaling refines germ layer boundaries in the marginal zone, but it is unknown the place this pathway occupies in the network comprising Churchill1 and Nodal. Here, we show that Xenopus churchill1 is expressed in the presumptive neuroectoderm at mid-blastula transition and during gastrulation, upregulates zeb2, prevents dll1 expression in the neuroectoderm, and favors neuroectoderm over endomesoderm development. Nodal signaling prevents dll1 expression in the endoderm but induces it in the presumptive mesoderm, from where it activates Notch1 and its target gene hes4 in the non-involuting marginal zone. We propose a model where Nodal and Churchill1 position Dll1/Notch1/Hes4 domains in the marginal zone, ensuring the delimitation between mesoderm and neuroectoderm.
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Affiliation(s)
- María Belén Favarolo
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Biología Celular e Histología/1° U.A. Departamento de Histología, Embriología, Biología Celular y Genética, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN), Laboratorio de Embriología Molecular "Prof. Dr. Andrés E. Carrasco", Buenos Aires, Argentina
| | - Diego R Revinski
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Biología Celular e Histología/1° U.A. Departamento de Histología, Embriología, Biología Celular y Genética, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN), Laboratorio de Embriología Molecular "Prof. Dr. Andrés E. Carrasco", Buenos Aires, Argentina
| | - Matías J Garavaglia
- Laboratorio de Bioinsumos, Instituto de Biotecnología, Universidad Nacional de Hurlingham, Buenos Aires, Argentina
| | - Silvia L López
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Biología Celular e Histología/1° U.A. Departamento de Histología, Embriología, Biología Celular y Genética, Buenos Aires, Argentina .,CONICET-Universidad de Buenos Aires, Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN), Laboratorio de Embriología Molecular "Prof. Dr. Andrés E. Carrasco", Buenos Aires, Argentina
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7
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Johnson K, Freedman S, Braun R, LaBonne C. Quantitative analysis of transcriptome dynamics provides novel insights into developmental state transitions. BMC Genomics 2022; 23:723. [PMID: 36273135 PMCID: PMC9588240 DOI: 10.1186/s12864-022-08953-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 10/19/2022] [Indexed: 11/30/2022] Open
Abstract
Background During embryogenesis, the developmental potential of initially pluripotent cells becomes progressively restricted as they transit to lineage restricted states. The pluripotent cells of Xenopus blastula-stage embryos are an ideal system in which to study cell state transitions during developmental decision-making, as gene expression dynamics can be followed at high temporal resolution. Results Here we use transcriptomics to interrogate the process by which pluripotent cells transit to four different lineage-restricted states: neural progenitors, epidermis, endoderm and ventral mesoderm, providing quantitative insights into the dynamics of Waddington’s landscape. Our findings provide novel insights into why the neural progenitor state is the default lineage state for pluripotent cells and uncover novel components of lineage-specific gene regulation. These data reveal an unexpected overlap in the transcriptional responses to BMP4/7 and Activin signaling and provide mechanistic insight into how the timing of signaling inputs such as BMP are temporally controlled to ensure correct lineage decisions. Conclusions Together these analyses provide quantitative insights into the logic and dynamics of developmental decision making in early embryos. They also provide valuable lineage-specific time series data following the acquisition of specific lineage states during development. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-022-08953-3.
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Affiliation(s)
- Kristin Johnson
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA.,NSF-Simons Center for Quantitative Biology, Northwestern University, Evanston, IL, 60208, USA
| | - Simon Freedman
- NSF-Simons Center for Quantitative Biology, Northwestern University, Evanston, IL, 60208, USA.,Department of Engineering Sciences and Applied Math, Northwestern University, Evanston, IL, USA
| | - Rosemary Braun
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA.,NSF-Simons Center for Quantitative Biology, Northwestern University, Evanston, IL, 60208, USA.,Department of Engineering Sciences and Applied Math, Northwestern University, Evanston, IL, USA.,Northwestern Institute On Complex Systems, Northwestern University, Evanston, IL, USA
| | - Carole LaBonne
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA. .,NSF-Simons Center for Quantitative Biology, Northwestern University, Evanston, IL, 60208, USA.
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8
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Differential nuclear import sets the timing of protein access to the embryonic genome. Nat Commun 2022; 13:5887. [PMID: 36202846 PMCID: PMC9537182 DOI: 10.1038/s41467-022-33429-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 09/16/2022] [Indexed: 02/02/2023] Open
Abstract
The development of a fertilized egg to an embryo requires the proper temporal control of gene expression. During cell differentiation, timing is often controlled via cascades of transcription factors (TFs). However, in early development, transcription is often inactive, and many TF levels stay constant, suggesting that alternative mechanisms govern the observed rapid and ordered onset of gene expression. Here, we find that in early embryonic development access of maternally deposited nuclear proteins to the genome is temporally ordered via importin affinities, thereby timing the expression of downstream targets. We quantify changes in the nuclear proteome during early development and find that nuclear proteins, such as TFs and RNA polymerases, enter the nucleus sequentially. Moreover, we find that the timing of nuclear proteins' access to the genome corresponds to the timing of downstream gene activation. We show that the affinity of proteins to importin is a major determinant in the timing of protein entry into embryonic nuclei. Thus, we propose a mechanism by which embryos encode the timing of gene expression in early development via biochemical affinities. This process could be critical for embryos to organize themselves before deploying the regulatory cascades that control cell identities.
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9
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Gil-Gálvez A, Jiménez-Gancedo S, Pérez-Posada A, Franke M, Acemel RD, Lin CY, Chou C, Su YH, Yu JK, Bertrand S, Schubert M, Escrivá H, Tena JJ, Gómez-Skarmeta JL. Gain of gene regulatory network interconnectivity at the origin of vertebrates. Proc Natl Acad Sci U S A 2022; 119:e2114802119. [PMID: 35263228 PMCID: PMC8931241 DOI: 10.1073/pnas.2114802119] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 01/21/2022] [Indexed: 12/18/2022] Open
Abstract
SignificanceIn this manuscript, we address an essential question in developmental and evolutionary biology: How have changes in gene regulatory networks contributed to the invertebrate-to-vertebrate transition? To address this issue, we perturbed four signaling pathways critical for body plan formation in the cephalochordate amphioxus and in zebrafish and compared the effects of such perturbations on gene expression and gene regulation in both species. Our data reveal that many developmental genes have gained response to these signaling pathways in the vertebrate lineage. Moreover, we show that the interconnectivity between these pathways is much higher in zebrafish than in amphioxus. We conclude that this increased signaling pathway complexity likely contributed to vertebrate morphological novelties during evolution.
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Affiliation(s)
- Alejandro Gil-Gálvez
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide-Junta de Andalucía, 41013 Seville, Spain
| | - Sandra Jiménez-Gancedo
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide-Junta de Andalucía, 41013 Seville, Spain
| | - Alberto Pérez-Posada
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide-Junta de Andalucía, 41013 Seville, Spain
| | - Martin Franke
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide-Junta de Andalucía, 41013 Seville, Spain
| | - Rafael D. Acemel
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide-Junta de Andalucía, 41013 Seville, Spain
| | - Che-Yi Lin
- Institute of Cellular and Organismic Biology, Academia Sinica, 11529 Taipei, Taiwan
| | - Cindy Chou
- Institute of Cellular and Organismic Biology, Academia Sinica, 11529 Taipei, Taiwan
| | - Yi-Hsien Su
- Institute of Cellular and Organismic Biology, Academia Sinica, 11529 Taipei, Taiwan
| | - Jr-Kai Yu
- Institute of Cellular and Organismic Biology, Academia Sinica, 11529 Taipei, Taiwan
- Marine Research Station, Institute of Cellular and Organismic Biology, Academia Sinica, 26242 Yilan, Taiwan
| | - Stephanie Bertrand
- Biologie Intégrative des Organismes Marins, Observatoire Océanologique, Sorbonne Université, CNRS, 66650 Banyuls-sur-Mer, France
| | - Michael Schubert
- Laboratoire de Biologie du Développement de Villefranche-sur-Mer, Institut de la Mer de Villefranche, Sorbonne Université, CNRS, 06230 Villefranche-sur-Mer, France
| | - Héctor Escrivá
- Biologie Intégrative des Organismes Marins, Observatoire Océanologique, Sorbonne Université, CNRS, 66650 Banyuls-sur-Mer, France
| | - Juan J. Tena
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide-Junta de Andalucía, 41013 Seville, Spain
| | - José Luis Gómez-Skarmeta
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide-Junta de Andalucía, 41013 Seville, Spain
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10
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Jansen C, Paraiso KD, Zhou JJ, Blitz IL, Fish MB, Charney RM, Cho JS, Yasuoka Y, Sudou N, Bright AR, Wlizla M, Veenstra GJC, Taira M, Zorn AM, Mortazavi A, Cho KWY. Uncovering the mesendoderm gene regulatory network through multi-omic data integration. Cell Rep 2022; 38:110364. [PMID: 35172134 PMCID: PMC8917868 DOI: 10.1016/j.celrep.2022.110364] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 10/30/2021] [Accepted: 01/19/2022] [Indexed: 01/01/2023] Open
Abstract
Mesendodermal specification is one of the earliest events in embryogenesis, where cells first acquire distinct identities. Cell differentiation is a highly regulated process that involves the function of numerous transcription factors (TFs) and signaling molecules, which can be described with gene regulatory networks (GRNs). Cell differentiation GRNs are difficult to build because existing mechanistic methods are low throughput, and high-throughput methods tend to be non-mechanistic. Additionally, integrating highly dimensional data composed of more than two data types is challenging. Here, we use linked self-organizing maps to combine chromatin immunoprecipitation sequencing (ChIP-seq)/ATAC-seq with temporal, spatial, and perturbation RNA sequencing (RNA-seq) data from Xenopus tropicalis mesendoderm development to build a high-resolution genome scale mechanistic GRN. We recover both known and previously unsuspected TF-DNA/TF-TF interactions validated through reporter assays. Our analysis provides insights into transcriptional regulation of early cell fate decisions and provides a general approach to building GRNs using highly dimensional multi-omic datasets.
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Affiliation(s)
- Camden Jansen
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA; Center for Complex Biological Systems, University of California, Irvine, CA, USA
| | - Kitt D Paraiso
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA; Center for Complex Biological Systems, University of California, Irvine, CA, USA
| | - Jeff J Zhou
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Ira L Blitz
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Margaret B Fish
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Rebekah M Charney
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Jin Sun Cho
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Yuuri Yasuoka
- Laboratory for Comprehensive Genomic Analysis, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Norihiro Sudou
- Department of Anatomy, School of Medicine, Toho University, Tokyo, Japan
| | - Ann Rose Bright
- Department of Molecular Developmental Biology, Radboud University, Nijmegen, the Netherlands
| | - Marcin Wlizla
- Division of Developmental Biology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Gert Jan C Veenstra
- Department of Molecular Developmental Biology, Radboud University, Nijmegen, the Netherlands
| | - Masanori Taira
- Department of Biological Sciences, Chuo University, Tokyo, Japan
| | - Aaron M Zorn
- Division of Developmental Biology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Ali Mortazavi
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA; Center for Complex Biological Systems, University of California, Irvine, CA, USA.
| | - Ken W Y Cho
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA; Center for Complex Biological Systems, University of California, Irvine, CA, USA.
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11
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McClay DR, Croce JC, Warner JF. Reprint of: Conditional specification of endomesoderm. Cells Dev 2021; 168:203731. [PMID: 34610899 DOI: 10.1016/j.cdev.2021.203731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 06/18/2021] [Accepted: 06/23/2021] [Indexed: 10/20/2022]
Abstract
Early in animal development many cells are conditionally specified based on observations that those cells can be directed toward alternate fates. The endomesoderm is so named because early specification produces cells that often have been observed to simultaneously express both early endoderm and mesoderm transcription factors. Experiments with these cells demonstrate that their progeny can directed entirely toward endoderm or mesoderm, whereas normally they establish both germ layers. This review examines the mechanisms that initiate the conditional endomesoderm state, its metastability, and the mechanisms that resolve that state into definitive endoderm and mesoderm.
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Affiliation(s)
- David R McClay
- Department of Biology, Duke University, Durham, NC, USA.
| | - Jenifer C Croce
- Sorbonne Université, CNRS, Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), Institut de la Mer de Villefranche, Villefranche-sur-Mer, France.
| | - Jacob F Warner
- Department of Biology, University of North Carolina, Wilmington, NC, USA.
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12
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Satou-Kobayashi Y, Kim JD, Fukamizu A, Asashima M. Temporal transcriptomic profiling reveals dynamic changes in gene expression of Xenopus animal cap upon activin treatment. Sci Rep 2021; 11:14537. [PMID: 34267234 PMCID: PMC8282838 DOI: 10.1038/s41598-021-93524-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 06/23/2021] [Indexed: 02/06/2023] Open
Abstract
Activin, a member of the transforming growth factor-β (TGF-β) superfamily of proteins, induces various tissues from the amphibian presumptive ectoderm, called animal cap explants (ACs) in vitro. However, it remains unclear how and to what extent the resulting cells recapitulate in vivo development. To comprehensively understand whether the molecular dynamics during activin-induced ACs differentiation reflect the normal development, we performed time-course transcriptome profiling of Xenopus ACs treated with 50 ng/mL of activin A, which predominantly induced dorsal mesoderm. The number of differentially expressed genes (DEGs) in response to activin A increased over time, and totally 9857 upregulated and 6663 downregulated DEGs were detected. 1861 common upregulated DEGs among all Post_activin samples included several Spemann's organizer genes. In addition, the temporal transcriptomes were clearly classified into four distinct groups in correspondence with specific features, reflecting stepwise differentiation into mesoderm derivatives, and a decline in the regulation of nuclear envelop and golgi. From the set of early responsive genes, we also identified the suppressor of cytokine signaling 3 (socs3) as a novel activin A-inducible gene. Our transcriptome data provide a framework to elucidate the transcriptional dynamics of activin-driven AC differentiation, reflecting the molecular characteristics of early normal embryogenesis.
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Affiliation(s)
- Yumeko Satou-Kobayashi
- grid.264706.10000 0000 9239 9995Strategic Innovation and Research Center, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo, 173-8605 Japan ,grid.264706.10000 0000 9239 9995Advanced Comprehensive Research Organization, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo, 173-8605 Japan ,grid.20515.330000 0001 2369 4728Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, 1-1-1, Tsukuba, Tennoudai Ibaraki 305-8577 Japan
| | - Jun-Dal Kim
- grid.20515.330000 0001 2369 4728Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, 1-1-1, Tsukuba, Tennoudai Ibaraki 305-8577 Japan ,grid.267346.20000 0001 2171 836XDivision of Complex Bioscience Research, Department of Research and Development, Institute of National Medicine, University of Toyama, 2630 Sugitani, Toyama, 930-0194 Japan
| | - Akiyoshi Fukamizu
- grid.20515.330000 0001 2369 4728Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, 1-1-1, Tsukuba, Tennoudai Ibaraki 305-8577 Japan
| | - Makoto Asashima
- grid.264706.10000 0000 9239 9995Strategic Innovation and Research Center, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo, 173-8605 Japan ,grid.264706.10000 0000 9239 9995Advanced Comprehensive Research Organization, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo, 173-8605 Japan ,grid.20515.330000 0001 2369 4728Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, 1-1-1, Tsukuba, Tennoudai Ibaraki 305-8577 Japan
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13
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McClay DR, Croce JC, Warner JF. Conditional specification of endomesoderm. Cells Dev 2021; 167:203716. [PMID: 34245941 DOI: 10.1016/j.cdev.2021.203716] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 06/18/2021] [Accepted: 06/23/2021] [Indexed: 10/20/2022]
Abstract
Early in animal development many cells are conditionally specified based on observations that those cells can be directed toward alternate fates. The endomesoderm is so named because early specification produces cells that often have been observed to simultaneously express both early endoderm and mesoderm transcription factors. Experiments with these cells demonstrate that their progeny can directed entirely toward endoderm or mesoderm, whereas normally they establish both germ layers. This review examines the mechanisms that initiate the conditional endomesoderm state, its metastability, and the mechanisms that resolve that state into definitive endoderm and mesoderm.
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Affiliation(s)
- David R McClay
- Department of Biology, Duke University, Durham, NC, USA.
| | - Jenifer C Croce
- Sorbonne Université, CNRS, Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), Institut de la Mer de Villefranche, Villefranche-sur-Mer, France.
| | - Jacob F Warner
- Department of Biology, University of North Carolina, Wilmington, NC, USA.
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14
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Lebedeva T, Aman AJ, Graf T, Niedermoser I, Zimmermann B, Kraus Y, Schatka M, Demilly A, Technau U, Genikhovich G. Cnidarian-bilaterian comparison reveals the ancestral regulatory logic of the β-catenin dependent axial patterning. Nat Commun 2021; 12:4032. [PMID: 34188050 PMCID: PMC8241978 DOI: 10.1038/s41467-021-24346-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 05/30/2021] [Indexed: 11/09/2022] Open
Abstract
In animals, body axis patterning is based on the concentration-dependent interpretation of graded morphogen signals, which enables correct positioning of the anatomical structures. The most ancient axis patterning system acting across animal phyla relies on β-catenin signaling, which directs gastrulation, and patterns the main body axis. However, within Bilateria, the patterning logic varies significantly between protostomes and deuterostomes. To deduce the ancestral principles of β-catenin-dependent axial patterning, we investigate the oral–aboral axis patterning in the sea anemone Nematostella—a member of the bilaterian sister group Cnidaria. Here we elucidate the regulatory logic by which more orally expressed β-catenin targets repress more aborally expressed β-catenin targets, and progressively restrict the initially global, maternally provided aboral identity. Similar regulatory logic of β-catenin-dependent patterning in Nematostella and deuterostomes suggests a common evolutionary origin of these processes and the equivalence of the cnidarian oral–aboral and the bilaterian posterior–anterior body axes. The authors show in Nematostella that the more orally expressed β-catenin targets repress the more aborally expressed β-catenin targets, thus patterning the oral-aboral axis. This likely represents the common mechanism of β-catenin-dependent axial patterning shared by Cnidaria and Bilateria.
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Affiliation(s)
- Tatiana Lebedeva
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, Vienna, Austria
| | - Andrew J Aman
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, Vienna, Austria
| | - Thomas Graf
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, Vienna, Austria
| | - Isabell Niedermoser
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, Vienna, Austria
| | - Bob Zimmermann
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, Vienna, Austria
| | - Yulia Kraus
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, Vienna, Austria.,Department of Evolutionary Biology, Faculty of Biology, Lomonosov Moscow State University, Leninskiye gory 1/12, Moscow, Russia
| | - Magdalena Schatka
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, Vienna, Austria
| | - Adrien Demilly
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, Vienna, Austria
| | - Ulrich Technau
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, Vienna, Austria
| | - Grigory Genikhovich
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, Vienna, Austria.
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15
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Abstract
The endoderm is the innermost germ layer that forms the linings of the respiratory and gastrointestinal tracts, and their associated organs, during embryonic development. Xenopus embryology experiments have provided fundamental insights into how the endoderm develops in vertebrates, including the critical role of TGFβ-signaling in endoderm induction,elucidating the gene regulatory networks controlling germ layer development and the key molecular mechanisms regulating endoderm patterning and morphogenesis. With new genetic, genomic, and imaging approaches, Xenopus is now routinely used to model human disease, discover mechanisms underlying endoderm organogenesis, and inform differentiation protocols for pluripotent stem cell differentiation and regenerative medicine applications. In this chapter, we review historical and current discoveries of endoderm development in Xenopus, then provide examples of modeling human disease and congenital defects of endoderm-derived organs using Xenopus.
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Affiliation(s)
- Nicole A Edwards
- Division of Developmental Biology, Center for Stem Cell and Organoid Medicine, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.
| | - Aaron M Zorn
- Division of Developmental Biology, Center for Stem Cell and Organoid Medicine, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States.
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16
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Castro Colabianchi AM, Tavella MB, Boyadjián López LE, Rubinstein M, Franchini LF, López SL. Segregation of brain and organizer precursors is differentially regulated by Nodal signaling at blastula stage. Biol Open 2021; 10:bio.051797. [PMID: 33563608 PMCID: PMC7928228 DOI: 10.1242/bio.051797] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The blastula Chordin- and Noggin-expressing (BCNE) center comprises animal-dorsal and marginal-dorsal cells of the amphibian blastula and contains the precursors of the brain and the gastrula organizer. Previous findings suggested that the BCNE behaves as a homogeneous cell population that only depends on nuclear β-catenin activity but does not require Nodal and later segregates into its descendants during gastrulation. In contrast to previous findings, in this work, we show that the BCNE does not behave as a homogeneous cell population in response to Nodal antagonists. In fact, we found that chordin.1 expression in a marginal subpopulation of notochordal precursors indeed requires Nodal input. We also establish that an animal BCNE subpopulation of cells that express both, chordin.1 and sox2 (a marker of pluripotent neuroectodermal cells), and gives rise to most of the brain, persisted at blastula stage after blocking Nodal. Therefore, Nodal signaling is required to define a population of chordin.1+ cells and to restrict the recruitment of brain precursors within the BCNE as early as at blastula stage. We discuss our findings in Xenopus in comparison to other vertebrate models, uncovering similitudes in early brain induction and delimitation through Nodal signaling. This article has an associated First Person interview with the first author of the paper. Summary: Nodal signaling is involved in the delimitation of the blastula cell populations that give rise to the brain and axial mesoderm in Xenopus.
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Affiliation(s)
- Aitana M Castro Colabianchi
- Universidad de Buenos Aires. Facultad de Medicina, Departamento de Biología Celular e Histología / 1° U.A. Departamento de Histología, Embriología, Biología Celular y Genética, Laboratorio de Embriología Molecular "Prof. Dr. Andrés E. Carrasco", Buenos Aires 1121, Argentina.,CONICET - Universidad de Buenos Aires. Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN), Universidad de Buenos Aires, Buenos Aires 1121, Argentina
| | - María B Tavella
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI) "Dr. Héctor N. Torres", Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires C1428, Argentina
| | - Laura E Boyadjián López
- Universidad de Buenos Aires. Facultad de Medicina, Departamento de Biología Celular e Histología / 1° U.A. Departamento de Histología, Embriología, Biología Celular y Genética, Laboratorio de Embriología Molecular "Prof. Dr. Andrés E. Carrasco", Buenos Aires 1121, Argentina.,CONICET - Universidad de Buenos Aires. Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN), Universidad de Buenos Aires, Buenos Aires 1121, Argentina
| | - Marcelo Rubinstein
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI) "Dr. Héctor N. Torres", Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires C1428, Argentina.,Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires 1428, Argentina
| | - Lucía F Franchini
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI) "Dr. Héctor N. Torres", Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires C1428, Argentina
| | - Silvia L López
- Universidad de Buenos Aires. Facultad de Medicina, Departamento de Biología Celular e Histología / 1° U.A. Departamento de Histología, Embriología, Biología Celular y Genética, Laboratorio de Embriología Molecular "Prof. Dr. Andrés E. Carrasco", Buenos Aires 1121, Argentina .,CONICET - Universidad de Buenos Aires. Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN), Universidad de Buenos Aires, Buenos Aires 1121, Argentina
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17
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Bright AR, van Genesen S, Li Q, Grasso A, Frölich S, van der Sande M, van Heeringen SJ, Veenstra GJC. Combinatorial transcription factor activities on open chromatin induce embryonic heterogeneity in vertebrates. EMBO J 2021; 40:e104913. [PMID: 33555045 PMCID: PMC8090851 DOI: 10.15252/embj.2020104913] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 12/21/2020] [Accepted: 12/24/2020] [Indexed: 12/15/2022] Open
Abstract
During vertebrate gastrulation, mesoderm is induced in pluripotent cells, concomitant with dorsal‐ventral patterning and establishing of the dorsal axis. We applied single‐cell chromatin accessibility and transcriptome analyses to explore the emergence of cellular heterogeneity during gastrulation in Xenopus tropicalis. Transcriptionally inactive lineage‐restricted genes exhibit relatively open chromatin in animal caps, whereas chromatin accessibility in dorsal marginal zone cells more closely reflects transcriptional activity. We characterized single‐cell trajectories and identified head and trunk organizer cell clusters in early gastrulae. By integrating chromatin accessibility and transcriptome data, we inferred the activity of transcription factors in single‐cell clusters and tested the activity of organizer‐expressed transcription factors in animal caps, alone or in combination. The expression profile induced by a combination of Foxb1 and Eomes most closely resembles that observed in the head organizer. Genes induced by Eomes, Otx2, or the Irx3‐Otx2 combination are enriched for maternally regulated H3K4me3 modifications, whereas Lhx8‐induced genes are marked more frequently by zygotically controlled H3K4me3. Taken together, our results show that transcription factors cooperate in a combinatorial fashion in generally open chromatin to orchestrate zygotic gene expression.
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Affiliation(s)
- Ann Rose Bright
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - Siebe van Genesen
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - Qingqing Li
- Biomedical Pioneering Innovation Center, Peking University, Beijing, China
| | - Alexia Grasso
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - Siebren Frölich
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - Maarten van der Sande
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - Simon J van Heeringen
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - Gert Jan C Veenstra
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
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18
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Abstract
The fertilized frog egg contains all the materials needed to initiate development of a new organism, including stored RNAs and proteins deposited during oogenesis, thus the earliest stages of development do not require transcription. The onset of transcription from the zygotic genome marks the first genetic switch activating the gene regulatory network that programs embryonic development. Zygotic genome activation occurs after an initial phase of transcriptional quiescence that continues until the midblastula stage, a period called the midblastula transition, which was first identified in Xenopus. Activation of transcription is programmed by maternally supplied factors and is regulated at multiple levels. A similar switch exists in most animals and is of great interest both to developmental biologists and to those interested in understanding nuclear reprogramming. Here we review in detail our knowledge on this major switch in transcription in Xenopus and place recent discoveries in the context of a decades old problem.
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19
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Mukherjee S, Chaturvedi P, Rankin SA, Fish MB, Wlizla M, Paraiso KD, MacDonald M, Chen X, Weirauch MT, Blitz IL, Cho KW, Zorn AM. Sox17 and β-catenin co-occupy Wnt-responsive enhancers to govern the endoderm gene regulatory network. eLife 2020; 9:58029. [PMID: 32894225 PMCID: PMC7498262 DOI: 10.7554/elife.58029] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 09/04/2020] [Indexed: 12/30/2022] Open
Abstract
Lineage specification is governed by gene regulatory networks (GRNs) that integrate the activity of signaling effectors and transcription factors (TFs) on enhancers. Sox17 is a key transcriptional regulator of definitive endoderm development, and yet, its genomic targets remain largely uncharacterized. Here, using genomic approaches and epistasis experiments, we define the Sox17-governed endoderm GRN in Xenopus gastrulae. We show that Sox17 functionally interacts with the canonical Wnt pathway to specify and pattern the endoderm while repressing alternative mesectoderm fates. Sox17 and β-catenin co-occupy hundreds of key enhancers. In some cases, Sox17 and β-catenin synergistically activate transcription apparently independent of Tcfs, whereas on other enhancers, Sox17 represses β-catenin/Tcf-mediated transcription to spatially restrict gene expression domains. Our findings establish Sox17 as a tissue-specific modifier of Wnt responses and point to a novel paradigm where genomic specificity of Wnt/β-catenin transcription is determined through functional interactions between lineage-specific Sox TFs and β-catenin/Tcf transcriptional complexes. Given the ubiquitous nature of Sox TFs and Wnt signaling, this mechanism has important implications across a diverse range of developmental and disease contexts.
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Affiliation(s)
- Shreyasi Mukherjee
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, United States.,University of Cincinnati, College of Medicine, Department of Pediatrics, Cincinnati, United States
| | - Praneet Chaturvedi
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, United States.,University of Cincinnati, College of Medicine, Department of Pediatrics, Cincinnati, United States
| | - Scott A Rankin
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, United States.,University of Cincinnati, College of Medicine, Department of Pediatrics, Cincinnati, United States
| | - Margaret B Fish
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, United States
| | - Marcin Wlizla
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, United States
| | - Kitt D Paraiso
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, United States.,Center for Complex Biological Systems, University of California, Irvine, Irvine, United States
| | - Melissa MacDonald
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, United States.,University of Cincinnati, College of Medicine, Department of Pediatrics, Cincinnati, United States
| | - Xiaoting Chen
- Center for Autoimmune Genomics and Etiology (CAGE), Divisions of Biomedical Informatics and Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, United States
| | - Matthew T Weirauch
- University of Cincinnati, College of Medicine, Department of Pediatrics, Cincinnati, United States.,Center for Autoimmune Genomics and Etiology (CAGE), Divisions of Biomedical Informatics and Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, United States
| | - Ira L Blitz
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, United States
| | - Ken Wy Cho
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, United States
| | - Aaron M Zorn
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, United States.,University of Cincinnati, College of Medicine, Department of Pediatrics, Cincinnati, United States
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20
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Paraiso KD, Blitz IL, Coley M, Cheung J, Sudou N, Taira M, Cho KWY. Endodermal Maternal Transcription Factors Establish Super-Enhancers during Zygotic Genome Activation. Cell Rep 2020; 27:2962-2977.e5. [PMID: 31167141 PMCID: PMC6610736 DOI: 10.1016/j.celrep.2019.05.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 03/30/2019] [Accepted: 05/01/2019] [Indexed: 01/06/2023] Open
Abstract
Elucidation of the sequence of events underlying the dynamic interaction
between transcription factors and chromatin states is essential. Maternal
transcription factors function at the top of the regulatory hierarchy to specify
the primary germ layers at the onset of zygotic genome activation (ZGA). We
focus on the formation of endoderm progenitor cells and examine the interactions
between maternal transcription factors and chromatin state changes underlying
the cell specification process. Endoderm-specific factors Otx1 and Vegt together
with Foxh1 orchestrate endoderm formation by coordinated binding to select
regulatory regions. These interactions occur before the deposition of enhancer
histone marks around the regulatory regions, and these TFs recruit RNA
polymerase II, regulate enhancer activity, and establish super-enhancers
associated with important endodermal genes. Therefore, maternal transcription
factors Otx1, Vegt, and Foxh1 combinatorially regulate the activity of
super-enhancers, which in turn activate key lineage-specifying genes during
ZGA. How do maternal transcription factors interact with chromatin regions to
coordinate the endodermal gene regulatory program? Paraiso et al. demonstrate
that combinatorial binding of maternal Otx1, Vegt, and Foxh1 to select enhancers
and super-enhancers in the genome controls endodermal cell fate specification
during zygotic gene activation.
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Affiliation(s)
- Kitt D Paraiso
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA; Center for Complex Biological Systems, University of California, Irvine, CA, USA
| | - Ira L Blitz
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Masani Coley
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Jessica Cheung
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Norihiro Sudou
- Department of Anatomy, Tokyo Women's Medical University, Tokyo, Japan
| | - Masanori Taira
- Department of Biological Sciences, Chuo University, Tokyo, Japan
| | - Ken W Y Cho
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA; Center for Complex Biological Systems, University of California, Irvine, CA, USA.
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21
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Paraiso KD, Cho JS, Yong J, Cho KWY. Early Xenopus gene regulatory programs, chromatin states, and the role of maternal transcription factors. Curr Top Dev Biol 2020; 139:35-60. [PMID: 32450966 PMCID: PMC11344482 DOI: 10.1016/bs.ctdb.2020.02.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
For decades, the early development of the Xenopus embryo has been an essential model system to study the gene regulatory mechanisms that govern cellular specification. At the top of the hierarchy of gene regulatory networks, maternally deposited transcription factors initiate this process and regulate the expression of zygotic genes that give rise to three distinctive germ layer cell types (ectoderm, mesoderm, and endoderm), and subsequent generation of organ precursors. The onset of germ layer specification is also closely coupled with changes associated with chromatin modifications. This review will examine the timing of maternal transcription factors initiating the zygotic genome activation, the epigenetic landscape of embryonic chromatin, and the network structure that governs the process.
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Affiliation(s)
- Kitt D Paraiso
- Department of Developmental and Cell Biology, University of California, Irvine, CA, United States; Center for Complex Biological Systems, University of California, Irvine, CA, United States
| | - Jin S Cho
- Department of Developmental and Cell Biology, University of California, Irvine, CA, United States
| | - Junseok Yong
- Department of Developmental and Cell Biology, University of California, Irvine, CA, United States
| | - Ken W Y Cho
- Department of Developmental and Cell Biology, University of California, Irvine, CA, United States; Center for Complex Biological Systems, University of California, Irvine, CA, United States.
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22
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Kumar S, Umair Z, Kumar V, Lee U, Choi SC, Kim J. Ventx1.1 competes with a transcriptional activator Xcad2 to regulate negatively its own expression. BMB Rep 2020. [PMID: 31068250 PMCID: PMC6605524 DOI: 10.5483/bmbrep.2019.52.6.085] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Dorsoventral patterning of body axis in vertebrate embryo is tightly controlled by a complex regulatory network of transcription factors. Ventx1.1 is known as a transcriptional repressor to inhibit dorsal mesoderm formation and neural differentiation in Xenopus. In an attempt to identify, using chromatin immunoprecipitation (ChIP)-Seq, genome-wide binding pattern of Ventx1.1 in Xenopus gastrulae, we observed that Ventx1.1 associates with its own 5′-flanking sequence. In this study, we present evidence that Ventx1.1 binds a cis-acting Ventx1.1 response element (VRE) in its own promoter, leading to repression of its own transcription. Site-directed mutagenesis of the VRE in the Ventx1.1 promoter significantly abrogated this inhibitory autoregulation of Ventx1.1 transcription. Notably, Ventx1.1 and Xcad2, an activator of Ventx1.1 transcription, competitively co-occupied the VRE in the Ventx1.1 promoter. In support of this, mutation of the VRE down-regulated basal and Xcad2-induced levels of Ventx1.1 promoter activity. In addition, overexpression of Ventx1.1 prevented Xcad2 from binding to the Ventx1.1 promoter, and vice versa. Taken together, these results suggest that Ventx1.1 negatively regulates its own transcription in competition with Xcad2, thereby fine-tuning its own expression levels during dorsoventral patterning of Xenopus early embryo.
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Affiliation(s)
- Shiv Kumar
- Department of Biochemistry, Institute of Cell Differentiation and Aging, College of Medicine, Hallym University, Chuncheon 24252, Korea
| | - Zobia Umair
- Department of Biochemistry, Institute of Cell Differentiation and Aging, College of Medicine, Hallym University, Chuncheon 24252, Korea
| | - Vijay Kumar
- Department of Biochemistry, Institute of Cell Differentiation and Aging, College of Medicine, Hallym University, Chuncheon 24252, Korea
| | - Unjoo Lee
- Department of Electrical Engineering, Hallym University, Chuncheon 24252, Korea
| | - Sun-Cheol Choi
- Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Jaebong Kim
- Department of Biochemistry, Institute of Cell Differentiation and Aging, College of Medicine, Hallym University, Chuncheon 24252, Korea
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23
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Seidl F, Levis NA, Schell R, Pfennig DW, Pfennig KS, Ehrenreich IM. Genome of Spea multiplicata, a Rapidly Developing, Phenotypically Plastic, and Desert-Adapted Spadefoot Toad. G3 (BETHESDA, MD.) 2019; 9:3909-3919. [PMID: 31578218 PMCID: PMC6893194 DOI: 10.1534/g3.119.400705] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 09/23/2019] [Indexed: 12/22/2022]
Abstract
Frogs and toads (anurans) are widely used to study many biological processes. Yet, few anuran genomes have been sequenced, limiting research on these organisms. Here, we produce a draft genome for the Mexican spadefoot toad, Spea multiplicata, which is a member of an unsequenced anuran clade. Atypically for amphibians, spadefoots inhabit deserts. Consequently, they possess many unique adaptations, including rapid growth and development, prolonged dormancy, phenotypic (developmental) plasticity, and adaptive, interspecies hybridization. We assembled and annotated a 1.07 Gb Sp. multiplicata genome containing 19,639 genes. By comparing this sequence to other available anuran genomes, we found gene amplifications in the gene families of nodal, hyas3, and zp3 in spadefoots, and obtained evidence that anuran genome size differences are partially driven by variability in intergenic DNA content. We also used the genome to identify genes experiencing positive selection and to study gene expression levels in spadefoot hybrids relative to their pure-species parents. Completion of the Sp. multiplicata genome advances efforts to determine the genetic bases of spadefoots' unique adaptations and enhances comparative genomic research in anurans.
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Affiliation(s)
- Fabian Seidl
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, and
| | - Nicholas A Levis
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Rachel Schell
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, and
| | - David W Pfennig
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Karin S Pfennig
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Ian M Ehrenreich
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, and
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24
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Rothenberg EV. Encounters across networks: Windows into principles of genomic regulation. Mar Genomics 2019; 44:3-12. [PMID: 30661741 DOI: 10.1016/j.margen.2019.01.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 01/06/2019] [Accepted: 01/06/2019] [Indexed: 12/13/2022]
Abstract
Gene regulatory networks account for the ability of the genome to program development in complex multi-cellular organisms. Such networks are based on principles of gene regulation by combinations of transcription factors that bind to specific cis-regulatory DNA sites to activate transcription. These cis-regulatory regions mediate logic processing at each network node, enabling progressive increases in organismal complexity with development. Gene regulatory network explanations of development have been shown to account for patterning and cell type diversification in fly and sea urchin embryonic systems, where networks are characterized by fast coupling between transcriptional inputs and changes in target gene transcription rates, and crucial cis-regulatory elements are concentrated relatively close to the protein coding sequences of the target genes, thus facilitating their identification. Stem cell-based development in post-embryonic mammalian systems also depends on gene networks, but differs from the fly and sea urchin systems. First, the number of regulatory elements per gene and the distances between regulatory elements and the genes they control are considerably larger, forcing searches via genome-wide transcription factor binding surveys rather than functional assays. Second, the intrinsic timing of network state transitions can be slowed considerably by the need to undo stem-cell chromatin configurations, which presumably add stability to stem-cell states but retard responses to transcription factor changes during differentiation. The dispersed, partially redundant cis-regulatory systems controlling gene expression and the slow state transition kinetics in these systems already reveal new insights and opportunities to extend understanding of the repertoire of gene networks and regulatory system logic.
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Affiliation(s)
- Ellen V Rothenberg
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
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25
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Prasad MS, Charney RM, García-Castro MI. Specification and formation of the neural crest: Perspectives on lineage segregation. Genesis 2019; 57:e23276. [PMID: 30576078 PMCID: PMC6570420 DOI: 10.1002/dvg.23276] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 12/17/2018] [Accepted: 12/18/2018] [Indexed: 12/21/2022]
Abstract
The neural crest is a fascinating embryonic population unique to vertebrates that is endowed with remarkable differentiation capacity. Thought to originate from ectodermal tissue, neural crest cells generate neurons and glia of the peripheral nervous system, and melanocytes throughout the body. However, the neural crest also generates many ectomesenchymal derivatives in the cranial region, including cell types considered to be of mesodermal origin such as cartilage, bone, and adipose tissue. These ectomesenchymal derivatives play a critical role in the formation of the vertebrate head, and are thought to be a key attribute at the center of vertebrate evolution and diversity. Further, aberrant neural crest cell development and differentiation is the root cause of many human pathologies, including cancers, rare syndromes, and birth malformations. In this review, we discuss the current findings of neural crest cell ontogeny, and consider tissue, cell, and molecular contributions toward neural crest formation. We further provide current perspectives into the molecular network involved during the segregation of the neural crest lineage.
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Affiliation(s)
- Maneeshi S Prasad
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, California
| | - Rebekah M Charney
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, California
| | - Martín I García-Castro
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, California
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26
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Yasuoka Y, Tando Y, Kubokawa K, Taira M. Evolution of cis-regulatory modules for the head organizer gene goosecoid in chordates: comparisons between Branchiostoma and Xenopus. ZOOLOGICAL LETTERS 2019; 5:27. [PMID: 31388442 PMCID: PMC6679436 DOI: 10.1186/s40851-019-0143-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 07/12/2019] [Indexed: 05/03/2023]
Abstract
BACKGROUND In cephalochordates (amphioxus), the notochord runs along the dorsal to the anterior tip of the body. In contrast, the vertebrate head is formed anterior to the notochord, as a result of head organizer formation in anterior mesoderm during early development. A key gene for the vertebrate head organizer, goosecoid (gsc), is broadly expressed in the dorsal mesoderm of amphioxus gastrula. Amphioxus gsc expression subsequently becomes restricted to the posterior notochord from the early neurula. This has prompted the hypothesis that a change in expression patterns of gsc led to development of the vertebrate head during chordate evolution. However, molecular mechanisms of head organizer evolution involving gsc have never been elucidated. RESULTS To address this question, we compared cis-regulatory modules of vertebrate organizer genes between amphioxus, Branchiostoma japonicum, and frogs, Xenopus laevis and Xenopus tropicalis. Here we show conservation and diversification of gene regulatory mechanisms through cis-regulatory modules for gsc, lim1/lhx1, and chordin in Branchiostoma and Xenopus. Reporter analysis using Xenopus embryos demonstrates that activation of gsc by Nodal/FoxH1 signal through the 5' upstream region, that of lim1 by Nodal/FoxH1 signal through the first intron, and that of chordin by Lim1 through the second intron, are conserved between amphioxus and Xenopus. However, activation of gsc by Lim1 and Otx through the 5' upstream region in Xenopus are not conserved in amphioxus. Furthermore, the 5' region of amphioxus gsc recapitulated the amphioxus-like posterior mesoderm expression of the reporter gene in transgenic Xenopus embryos. CONCLUSIONS On the basis of this study, we propose a model, in which the gsc gene acquired the cis-regulatory module bound with Lim1 and Otx at its 5' upstream region to be activated persistently in anterior mesoderm, in the vertebrate lineage. Because Gsc globally represses trunk (notochord) genes in the vertebrate head organizer, this cooption of gsc in vertebrates appears to have resulted in inhibition of trunk genes and acquisition of the head organizer and its derivative prechordal plate.
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Affiliation(s)
- Yuuri Yasuoka
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 Japan
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa, 904-0495 Japan
- Laboratory for Comprehensive Genomic Analysis, RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045 Japan
| | - Yukiko Tando
- Center for Advance Marine Research, Ocean Research Institute, The University of Tokyo, 1-15-1, Minamidai, Nakano-ku, Tokyo, 164-8639 Japan
- Present address: Cell Resource Center for Biomedical Research, Institute of Development, Aging and Cancer (IDAC), Tohoku University, 4-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575 Japan
| | - Kaoru Kubokawa
- Center for Advance Marine Research, Ocean Research Institute, The University of Tokyo, 1-15-1, Minamidai, Nakano-ku, Tokyo, 164-8639 Japan
- Present address: SIRC, Teikyo University, 2-11-1, Itabashi-ku, Tokyo, 173-8605 Japan
| | - Masanori Taira
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 Japan
- Present address: Department of Biological Sciences, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo, 112-8551 Japan
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Affiliation(s)
- Aaron M Zorn
- Division of Developmental Biology, Perinatal Institute, Center for Stem Cell and Organoid Medicine, Cincinnati Children's Research Foundation and the University of Cincinnati College of Medicine, Cincinnati OH, 45229, United States.
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28
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Favarolo MB, López SL. Notch signaling in the division of germ layers in bilaterian embryos. Mech Dev 2018; 154:122-144. [PMID: 29940277 DOI: 10.1016/j.mod.2018.06.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 06/08/2018] [Accepted: 06/18/2018] [Indexed: 01/09/2023]
Abstract
Bilaterian embryos are triploblastic organisms which develop three complete germ layers (ectoderm, mesoderm, and endoderm). While the ectoderm develops mainly from the animal hemisphere, there is diversity in the location from where the endoderm and the mesoderm arise in relation to the animal-vegetal axis, ranging from endoderm being specified between the ectoderm and mesoderm in echinoderms, and the mesoderm being specified between the ectoderm and the endoderm in vertebrates. A common feature is that part of the mesoderm segregates from an ancient bipotential endomesodermal domain. The process of segregation is noisy during the initial steps but it is gradually refined. In this review, we discuss the role of the Notch pathway in the establishment and refinement of boundaries between germ layers in bilaterians, with special focus on its interaction with the Wnt/β-catenin pathway.
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Affiliation(s)
- María Belén Favarolo
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Biología Celular y Neurociencias "Prof. E. De Robertis" (IBCN), Facultad de Medicina, Laboratorio de Embriología Molecular "Prof. Dr. Andrés E. Carrasco", Buenos Aires, Argentina
| | - Silvia L López
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Biología Celular y Neurociencias "Prof. E. De Robertis" (IBCN), Facultad de Medicina, Laboratorio de Embriología Molecular "Prof. Dr. Andrés E. Carrasco", Buenos Aires, Argentina.
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