1
|
Kurup AJ, Bailet F, Fürthauer M. Myosin1G promotes Nodal signaling to control zebrafish left-right asymmetry. Nat Commun 2024; 15:6547. [PMID: 39095343 PMCID: PMC11297164 DOI: 10.1038/s41467-024-50868-y] [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: 09/03/2023] [Accepted: 07/22/2024] [Indexed: 08/04/2024] Open
Abstract
Myosin1D (Myo1D) has recently emerged as a conserved regulator of animal Left-Right (LR) asymmetry that governs the morphogenesis of the vertebrate central LR Organizer (LRO). In addition to Myo1D, the zebrafish genome encodes the closely related Myo1G. Here we show that while Myo1G also controls LR asymmetry, it does so through an entirely different mechanism. Myo1G promotes the Nodal-mediated transfer of laterality information from the LRO to target tissues. At the cellular level, Myo1G is associated with endosomes positive for the TGFβ signaling adapter SARA. myo1g mutants have fewer SARA-positive Activin receptor endosomes and a reduced responsiveness to Nodal ligands that results in a delay of left-sided Nodal propagation and tissue-specific laterality defects in organs that are most distant from the LRO. Additionally, Myo1G promotes signaling by different Nodal ligands in specific biological contexts. Our findings therefore identify Myo1G as a context-dependent regulator of the Nodal signaling pathway.
Collapse
|
2
|
McNamara HM, Jia BZ, Guyer A, Parot VJ, Dobbs C, Schier AF, Cohen AE, Lord ND. Optogenetic control of Nodal signaling patterns. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.11.588875. [PMID: 38645239 PMCID: PMC11030342 DOI: 10.1101/2024.04.11.588875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
A crucial step in early embryogenesis is the establishment of spatial patterns of signaling activity. Tools to perturb morphogen signals with high resolution in space and time can help reveal how embryonic cells decode these signals to make appropriate fate decisions. Here, we present new optogenetic reagents and an experimental pipeline for creaHng designer Nodal signaling patterns in live zebrafish embryos. Nodal receptors were fused to the light-sensitive heterodimerizing pair Cry2/CIB1N, and the Type II receptor was sequestered to the cytosol. The improved optoNodal2 reagents eliminate dark activity and improve response kinetics, without sacrificing dynamic range. We adapted an ultra-widefield microscopy platform for parallel light patterning in up to 36 embryos and demonstrated precise spatial control over Nodal signaling activity and downstream gene expression. Patterned Nodal activation drove precisely controlled internalization of endodermal precursors. Further, we used patterned illumination to generate synthetic signaling patterns in Nodal signaling mutants, rescuing several characteristic developmental defects. This study establishes an experimental toolkit for systematic exploration of Nodal signaling patterns in live embryos.
Collapse
Affiliation(s)
| | - Bill Z. Jia
- Department of Systems Biology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Alison Guyer
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Vicente J. Parot
- Institute for Biological and Medical Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Caleb Dobbs
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | | | - Adam E. Cohen
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Department of Physics, Harvard University, Cambridge, MA, USA
| | - Nathan D. Lord
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, USA
- McGowan Institute of Regenerative Medicine, University of Pittsburgh, Pittsburgh, USA
| |
Collapse
|
3
|
Huljev K, Shamipour S, Pinheiro D, Preusser F, Steccari I, Sommer CM, Naik S, Heisenberg CP. A hydraulic feedback loop between mesendoderm cell migration and interstitial fluid relocalization promotes embryonic axis formation in zebrafish. Dev Cell 2023; 58:582-596.e7. [PMID: 36931269 DOI: 10.1016/j.devcel.2023.02.016] [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: 01/10/2022] [Revised: 08/31/2022] [Accepted: 02/20/2023] [Indexed: 03/18/2023]
Abstract
Interstitial fluid (IF) accumulation between embryonic cells is thought to be important for embryo patterning and morphogenesis. Here, we identify a positive mechanical feedback loop between cell migration and IF relocalization and find that it promotes embryonic axis formation during zebrafish gastrulation. We show that anterior axial mesendoderm (prechordal plate [ppl]) cells, moving in between the yolk cell and deep cell tissue to extend the embryonic axis, compress the overlying deep cell layer, thereby causing IF to flow from the deep cell layer to the boundary between the yolk cell and the deep cell layer, directly ahead of the advancing ppl. This IF relocalization, in turn, facilitates ppl cell protrusion formation and migration by opening up the space into which the ppl moves and, thereby, the ability of the ppl to trigger IF relocalization by pushing against the overlying deep cell layer. Thus, embryonic axis formation relies on a hydraulic feedback loop between cell migration and IF relocalization.
Collapse
Affiliation(s)
- Karla Huljev
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Shayan Shamipour
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Diana Pinheiro
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria
| | - Friedrich Preusser
- Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück centre for Molecular Medicine in the Helmholtz Association (MDC), 13125 Berlin, Germany
| | - Irene Steccari
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | | | - Suyash Naik
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | | |
Collapse
|
4
|
Wang R, Guo S, Yang L. Tal2 is required for generation of GABAergic neurons in the zebrafish midbrain. Dev Dyn 2023; 252:263-275. [PMID: 36063149 DOI: 10.1002/dvdy.534] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 08/22/2022] [Accepted: 08/28/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In the zebrafish midbrain, GABAergic neurons develop from precursors located in the nucleus of the medial longitudinal fasciculus (nMLF). However, the precise mechanisms that underline generation of the nMLF GABAergic neuron are poorly understood. RESULTS GABAergic neurons in the nMLF co-express transcription factors tal2, gata2a, gata3, and nkx1.2lb. The Nodal-related gene and shh signaling are required for differentiation of nMLF GABAergic neuron precursors. Tal2 is important for nMLF GABAergic neurogenesis. Disruption of Tal2, embryos completely lack the GABA-synthesizing enzyme glutamic acid decarboxylase 67 gene (gad67) expressing cells in the nMLF, and the whole nkx1.2lb expressing cells in the midbrain. Although almost all tal2-expressing cells in the diencephalon and/or nMLF are gata2a- and gata3-positive, simultaneous knockdown of gata2a and gata3 does not affect either tal2 or gad67 expression. CONCLUSIONS In the zebrafish midbrain, expression of tal2, gata2a, and/or gata3 is independent of each other. The function of gata2a and gata3 is dispensable for generation of GABAergic neuron in the nMLF. This suggests that the functional connections of the regulatory genes leading to generation of nMLF GABAergic neurons have diverged between mouse and zebrafish.
Collapse
Affiliation(s)
- Ruihong Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
| | - Shaojuan Guo
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
| | - Lixin Yang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
| |
Collapse
|
5
|
Ziermann JM. Overview of Head Muscles with Special Emphasis on Extraocular Muscle Development. ADVANCES IN ANATOMY, EMBRYOLOGY, AND CELL BIOLOGY 2023; 236:57-80. [PMID: 37955771 DOI: 10.1007/978-3-031-38215-4_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2023]
Abstract
The head is often considered the most complex part of the vertebrate body as many different cell types contribute to a huge variation of structures in a very limited space. Most of these cell types also interact with each other to ensure the proper development of skull, brain, muscles, nerves, connective tissue, and blood vessels. While there are general mechanisms that are true for muscle development all over the body, the head and postcranial muscle development differ from each other. In the head, specific gene regulatory networks underlie the differentiation in subgroups, which include extraocular muscles, muscles of mastication, muscles of facial expression, laryngeal and pharyngeal muscles, as well as cranial nerve innervated neck muscles. Here, I provide an overview of the difference between head and trunk muscle development. This is followed by a short excursion to the cardiopharyngeal field which gives rise to heart and head musculature and a summary of pharyngeal arch muscle development, including interactions between neural crest cells, mesodermal cells, and endodermal signals. Lastly, a more detailed description of the eye development, tissue interactions, and involved genes is provided.
Collapse
|
6
|
Forrest K, Barricella AC, Pohar SA, Hinman AM, Amack JD. Understanding laterality disorders and the left-right organizer: Insights from zebrafish. Front Cell Dev Biol 2022; 10:1035513. [PMID: 36619867 PMCID: PMC9816872 DOI: 10.3389/fcell.2022.1035513] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 12/12/2022] [Indexed: 12/24/2022] Open
Abstract
Vital internal organs display a left-right (LR) asymmetric arrangement that is established during embryonic development. Disruption of this LR asymmetry-or laterality-can result in congenital organ malformations. Situs inversus totalis (SIT) is a complete concordant reversal of internal organs that results in a low occurrence of clinical consequences. Situs ambiguous, which gives rise to Heterotaxy syndrome (HTX), is characterized by discordant development and arrangement of organs that is associated with a wide range of birth defects. The leading cause of health problems in HTX patients is a congenital heart malformation. Mutations identified in patients with laterality disorders implicate motile cilia in establishing LR asymmetry. However, the cellular and molecular mechanisms underlying SIT and HTX are not fully understood. In several vertebrates, including mouse, frog and zebrafish, motile cilia located in a "left-right organizer" (LRO) trigger conserved signaling pathways that guide asymmetric organ development. Perturbation of LRO formation and/or function in animal models recapitulates organ malformations observed in SIT and HTX patients. This provides an opportunity to use these models to investigate the embryological origins of laterality disorders. The zebrafish embryo has emerged as an important model for investigating the earliest steps of LRO development. Here, we discuss clinical characteristics of human laterality disorders, and highlight experimental results from zebrafish that provide insights into LRO biology and advance our understanding of human laterality disorders.
Collapse
Affiliation(s)
- Kadeen Forrest
- Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY, United States
| | - Alexandria C. Barricella
- Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY, United States
| | - Sonny A. Pohar
- Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY, United States
| | - Anna Maria Hinman
- Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY, United States
| | - Jeffrey D. Amack
- Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY, United States
- BioInspired Syracuse: Institute for Material and Living Systems, Syracuse, NY, United States
| |
Collapse
|
7
|
Hill CS. Establishment and interpretation of NODAL and BMP signaling gradients in early vertebrate development. Curr Top Dev Biol 2022; 149:311-340. [PMID: 35606059 DOI: 10.1016/bs.ctdb.2021.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Transforming growth factor β (TGF-β) family ligands play crucial roles in orchestrating early embryonic development. Most significantly, two family members, NODAL and BMP form signaling gradients and indeed in fish, frogs and sea urchins these two opposing gradients are sufficient to organize a complete embryonic axis. This review focuses on how these gradients are established and interpreted during early vertebrate development. The review highlights key principles that are emerging, in particular the importance of signaling duration as well as ligand concentration in both gradient generation and their interpretation. Feedforward and feedback loops involving other signaling pathways are also essential for providing spatial and temporal information downstream of the NODAL and BMP signaling pathways. Finally, new data suggest the existence of buffering mechanisms, whereby early signaling defects can be readily corrected downstream later in development, suggesting that signaling gradients do not have to be as precise as previously thought.
Collapse
Affiliation(s)
- Caroline S Hill
- Developmental Signalling Laboratory, The Francis Crick Institute, London, United Kingdom.
| |
Collapse
|
8
|
Hasanpour S, Eagderi S, Poorbagher H, Angrand PO, Hasanpour M, Lashkarbolok M. The effect of Activin pathway modulation on the expression of both pluripotency and differentiation markers during early zebrafish development compared with other vertebrates. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2021; 336:562-575. [PMID: 34254429 DOI: 10.1002/jez.b.23070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 05/22/2021] [Accepted: 06/24/2021] [Indexed: 11/09/2022]
Abstract
Activin-like factors control many developmental processes, including pluripotency maintenance and differentiation. Although Activin-like factors' action in mesendoderm induction has been demonstrated in zebrafish, their involvement in preserving the stemness remains unknown. To investigate the role of maternal Activin-like factors, their effects were promoted or blocked using synthetic human Activin A or SB-431542 treatments respectively until the maternal to zygotic transition. To study the role of zygotic Activin-like factors, SB-431542 treatment was also applied after the maternal to zygotic transition. The effect of the pharmacological modulations of the Activin/Smad pathway was then studied on the mRNA expressions of the ndr1, ndr2, tbxta (no tail/ntl) as the differentiation index, mych, nanog, and oct4 (pou5f3) as the pluripotency markers of the zebrafish embryonic cells as well as sox17 as a definitive endoderm marker. Expression of the target genes was measured at the 16-cell, 256-cell, 1K-cell, oblong, dome, and shield stages using the real-time quantitative polymerase chain reaction (RT-qPCR). Activation of the maternal Activin signaling pathway led to an increase in zygotic expression of the tbxta, particularly marked at the oblong stage. In other words, promotion of the maternal Activin/Smad pathway induced differentiation by advancing the major peaks of ndr1 and nanog, thereby eliciting tbxta expression. Whereas suppression of the maternal or zygotic Activin/Smad pathway sustained the pluripotency by preventing the major peaks of ndr1 and nanog as well as tbxta encoding.
Collapse
Affiliation(s)
- Shaghayegh Hasanpour
- Department of Fisheries, Faculty of Natural Resources, University of Tehran, Karaj, Iran.,Development and Biosystematic Lab., Department of Fisheries and Animal Sciences, Faculty of Natural Resources, University of Tehran, Karaj, Iran
| | - Soheil Eagderi
- Department of Fisheries, Faculty of Natural Resources, University of Tehran, Karaj, Iran
| | - Hadi Poorbagher
- Department of Fisheries, Faculty of Natural Resources, University of Tehran, Karaj, Iran
| | - Pierre-Olivier Angrand
- Univ Lille, CNRS UMR 9020, Inserm UMR-S 1277, CHU Lille, Centre Oscar Lambret, UMR Canther-Cancer Heterogeneity, Plasticity and Resistance to Therapies, Lille, France
| | - Mohammad Hasanpour
- Department of Neurosurgery, Iran University of Medical Sciences, Tehran, Iran
| | - Maryam Lashkarbolok
- Department of Radiology, Isfahan University of Medical Sciences, Isfahan, Iran
| |
Collapse
|
9
|
Venturini V, Pezzano F, Català Castro F, Häkkinen HM, Jiménez-Delgado S, Colomer-Rosell M, Marro M, Tolosa-Ramon Q, Paz-López S, Valverde MA, Weghuber J, Loza-Alvarez P, Krieg M, Wieser S, Ruprecht V. The nucleus measures shape changes for cellular proprioception to control
dynamic cell behavior. Science 2020; 370:370/6514/eaba2644. [DOI: 10.1126/science.aba2644] [Citation(s) in RCA: 131] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 06/29/2020] [Accepted: 08/28/2020] [Indexed: 12/15/2022]
Abstract
The physical microenvironment regulates cell behavior during tissue
development and homeostasis. How single cells decode information about their
geometrical shape under mechanical stress and physical space constraints
within tissues remains largely unknown. Here, using a zebrafish model, we
show that the nucleus, the biggest cellular organelle, functions as an
elastic deformation gauge that enables cells to measure cell shape
deformations. Inner nuclear membrane unfolding upon nucleus stretching
provides physical information on cellular shape changes and adaptively
activates a calcium-dependent mechanotransduction pathway, controlling
actomyosin contractility and migration plasticity. Our data support that the
nucleus establishes a functional module for cellular proprioception that
enables cells to sense shape variations for adapting cellular behavior to
their microenvironment.
Collapse
Affiliation(s)
- Valeria Venturini
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Spain
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain
| | - Fabio Pezzano
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain
| | - Frederic Català Castro
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Spain
| | - Hanna-Maria Häkkinen
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain
| | - Senda Jiménez-Delgado
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain
| | - Mariona Colomer-Rosell
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Spain
| | - Monica Marro
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Spain
| | - Queralt Tolosa-Ramon
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain
| | - Sonia Paz-López
- Laboratory of Molecular Physiology, Department of Experimental and Health Sciences, Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Miguel A. Valverde
- Laboratory of Molecular Physiology, Department of Experimental and Health Sciences, Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Julian Weghuber
- School of Engineering, University of Applied Sciences Upper Austria, Stelzhamerstraße 23, Wels 4600, Austria
| | - Pablo Loza-Alvarez
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Spain
| | - Michael Krieg
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Spain
| | - Stefan Wieser
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Spain
| | - Verena Ruprecht
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain
- Department of Experimental and Health Sciences, Universitat Pompeu Fabra (UPF), Barcelona, Spain
| |
Collapse
|
10
|
Loosemore RG, Matthaei SD, Stanger TC. An enigmatic translocation of the vertebrate primordial eye field. BMC Evol Biol 2020; 20:129. [PMID: 33008334 PMCID: PMC7531155 DOI: 10.1186/s12862-020-01693-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 09/17/2020] [Indexed: 11/10/2022] Open
Abstract
The primordial eye field of the vertebrate embryo is a single entity of retinal progenitor cells spanning the anterior neural plate before bifurcating to form bilateral optic vesicles. Here we review fate mapping data from zebrafish suggesting that prior to evagination of the optic vesicles the eye field may undergo a Maypole-plait migration of progenitor cells through the midline influenced by the anteriorly subducting diencephalon. Such an enigmatic translocation of scaffolding progenitors could have evolutionary significance if pointing, by way of homology, to an ancient mechanism for transition of the single eye field in chordates to contralateral eye fields in vertebrates.
Collapse
Affiliation(s)
- R G Loosemore
- Maclean District Hospital, Union St, Maclean, NSW, 2463, Australia.
| | | | - T C Stanger
- Maclean District Hospital, Maclean, Australia
| |
Collapse
|
11
|
Abstract
Gastrulation is a critical early morphogenetic process of animal development, during which the three germ layers; mesoderm, endoderm and ectoderm, are rearranged by internalization movements. Concurrent epiboly movements spread and thin the germ layers while convergence and extension movements shape them into an anteroposteriorly elongated body with head, trunk, tail and organ rudiments. In zebrafish, gastrulation follows the proliferative and inductive events that establish the embryonic and extraembryonic tissues and the embryonic axis. Specification of these tissues and embryonic axes are controlled by the maternal gene products deposited in the egg. These early maternally controlled processes need to generate sufficient cell numbers and establish the embryonic polarity to ensure normal gastrulation. Subsequently, after activation of the zygotic genome, the zygotic gene products govern mesoderm and endoderm induction and germ layer patterning. Gastrulation is initiated during the maternal-to-zygotic transition, a process that entails both activation of the zygotic genome and downregulation of the maternal transcripts. Genomic studies indicate that gastrulation is largely controlled by the zygotic genome. Nonetheless, genetic studies that investigate the relative contributions of maternal and zygotic gene function by comparing zygotic, maternal and maternal zygotic mutant phenotypes, reveal significant contribution of maternal gene products, transcripts and/or proteins, that persist through gastrulation, to the control of gastrulation movements. Therefore, in zebrafish, the maternally expressed gene products not only set the stage for, but they also actively participate in gastrulation morphogenesis.
Collapse
Affiliation(s)
- Lilianna Solnica-Krezel
- Department of Developmental Biology and Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO, United States.
| |
Collapse
|
12
|
|
13
|
Economou AD, Hill CS. Temporal dynamics in the formation and interpretation of Nodal and BMP morphogen gradients. Curr Top Dev Biol 2019; 137:363-389. [PMID: 32143749 DOI: 10.1016/bs.ctdb.2019.10.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
One of the most powerful ideas in developmental biology has been that of the morphogen gradient. In the classical view, a signaling molecule is produced at a local source from where it diffuses, resulting in graded levels across the tissue. This gradient provides positional information, with thresholds in the level of the morphogen determining the position of different cell fates. While experimental studies have uncovered numerous potential morphogens in biological systems, it is becoming increasingly apparent that one important feature, not captured in the simple model, is the role of time in both the formation and interpretation of morphogen gradients. We will focus on two members of the transforming growth factor-β family that are known to play a vital role as morphogens in early vertebrate development: the Nodals and the bone morphogenetic proteins (BMPs). Primarily drawing on the early zebrafish embryo, we will show how recent studies have demonstrated the importance of feedback and other interactions that evolve through time, in shaping morphogen gradients. We will further show how rather than simply reading out levels of a morphogen, the duration of ligand exposure can be a crucial determinant of how cells interpret morphogens, in particular through the unfolding of downstream transcriptional events and in their interactions with other pathways.
Collapse
Affiliation(s)
- Andrew D Economou
- Developmental Signalling Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Caroline S Hill
- Developmental Signalling Laboratory, The Francis Crick Institute, London, United Kingdom.
| |
Collapse
|
14
|
Abstract
Soon after fertilization the zebrafish embryo generates the pool of cells that will give rise to the germline and the three somatic germ layers of the embryo (ectoderm, mesoderm and endoderm). As the basic body plan of the vertebrate embryo emerges, evolutionarily conserved developmental signaling pathways, including Bmp, Nodal, Wnt, and Fgf, direct the nearly totipotent cells of the early embryo to adopt gene expression profiles and patterns of cell behavior specific to their eventual fates. Several decades of molecular genetics research in zebrafish has yielded significant insight into the maternal and zygotic contributions and mechanisms that pattern this vertebrate embryo. This new understanding is the product of advances in genetic manipulations and imaging technologies that have allowed the field to probe the cellular, molecular and biophysical aspects underlying early patterning. The current state of the field indicates that patterning is governed by the integration of key signaling pathways and physical interactions between cells, rather than a patterning system in which distinct pathways are deployed to specify a particular cell fate. This chapter focuses on recent advances in our understanding of the genetic and molecular control of the events that impart cell identity and initiate the patterning of tissues that are prerequisites for or concurrent with movements of gastrulation.
Collapse
Affiliation(s)
- Florence L Marlow
- Icahn School of Medicine Mount Sinai Department of Cell, Developmental and Regenerative Biology, New York, NY, United States.
| |
Collapse
|
15
|
Harding P, Moosajee M. The Molecular Basis of Human Anophthalmia and Microphthalmia. J Dev Biol 2019; 7:jdb7030016. [PMID: 31416264 PMCID: PMC6787759 DOI: 10.3390/jdb7030016] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 08/08/2019] [Accepted: 08/08/2019] [Indexed: 12/16/2022] Open
Abstract
Human eye development is coordinated through an extensive network of genetic signalling pathways. Disruption of key regulatory genes in the early stages of eye development can result in aborted eye formation, resulting in an absent eye (anophthalmia) or a small underdeveloped eye (microphthalmia) phenotype. Anophthalmia and microphthalmia (AM) are part of the same clinical spectrum and have high genetic heterogeneity, with >90 identified associated genes. By understanding the roles of these genes in development, including their temporal expression, the phenotypic variation associated with AM can be better understood, improving diagnosis and management. This review describes the genetic and structural basis of eye development, focusing on the function of key genes known to be associated with AM. In addition, we highlight some promising avenues of research involving multiomic approaches and disease modelling with induced pluripotent stem cell (iPSC) technology, which will aid in developing novel therapies.
Collapse
Affiliation(s)
| | - Mariya Moosajee
- UCL Institute of Ophthalmology, London EC1V 9EL, UK.
- Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK.
- Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK.
| |
Collapse
|
16
|
Characterization of paralogous uncx transcription factor encoding genes in zebrafish. Gene X 2019; 721S:100011. [PMID: 31193955 PMCID: PMC6543554 DOI: 10.1016/j.gene.2019.100011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 02/12/2019] [Accepted: 02/15/2019] [Indexed: 12/23/2022] Open
Abstract
The paired-type homeodomain transcription factor Uncx is involved in multiple processes of embryogenesis in vertebrates. Reasoning that zebrafish genes uncx4.1 and uncx are orthologs of mouse Uncx, we studied their genomic environment and developmental expression. Evolutionary analyses indicate the zebrafish uncx genes as being paralogs deriving from teleost-specific whole-genome duplication. Whole-mount in situ mRNA hybridization of uncx transcripts in zebrafish embryos reveals novel expression domains, confirms those previously known, and suggests sub-functionalization of paralogs. Using genetic mutants and pharmacological inhibitors, we investigate the role of signaling pathways on the expression of zebrafish uncx genes in developing somites. In identifying putative functional role(s) of zebrafish uncx genes, we hypothesized that they encode transcription factors that coordinate growth and innervation of somitic muscles. The Uncx4.1 and Uncx genes derive from the teleost-specific whole-genome duplication. Uncx genes are expressed during embryogenesis in unique and overlapping domains. Uncx gene expression during somite differentiation is regulated by FGF signaling. Synteny and expression profiles correlate Uncx genes with axon guidance.
Collapse
Key Words
- AP, antero-posterior
- Ace, acerebellar
- CAMP, conserved ancestral microsyntenic pairs
- CNE, conserved non-coding elements
- CRM, cis-regulatory module
- CS, Corpuscle of Stannius
- CaP, caudal primary motor neuron axons
- Ce, cerebellum
- Development
- Di, diencephalon
- Elfn1, Extracellular Leucine Rich Repeat And Fibronectin Type III Domain Containing 1
- Ey, eye
- FB, forebrain
- FGF, fibroblast growth factor
- Flh, floating head
- HB, hindbrain
- HM, hybridization mix
- Hy, hypothalamus
- MO, morpholino
- Mical, molecule interacting with CasL
- No, notochord
- OP, olfactory placode
- OT, optic tectum
- PA, pharyngeal arches
- PSM, presomitic mesoderm
- SC, spinal cord
- Shh, sonic hedgehog
- Signaling pathway
- So, somites
- Synteny
- TSGD
- TSGD, teleost-specific genome duplication
- Te, telencephalon
- Th, thalamus
- Uncx
- VLP, ventro-lateral-posterior
- WIHC, whole-mount immunohistochemistry
- WISH, whole-mount in situ hybridization
- YE, yolk extension
- Yo, yolk
- Zebrafish
- cyc, cyclops
- fss, fused-somites
- hpf, hours post fertilization
- ptc, patched
- smu, slow-muscle-omitted
- syu, sonic-you
- yot, you-too
Collapse
|
17
|
Čapek D, Smutny M, Tichy AM, Morri M, Janovjak H, Heisenberg CP. Light-activated Frizzled7 reveals a permissive role of non-canonical wnt signaling in mesendoderm cell migration. eLife 2019; 8:e42093. [PMID: 30648973 PMCID: PMC6365057 DOI: 10.7554/elife.42093] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 01/14/2019] [Indexed: 12/11/2022] Open
Abstract
Non-canonical Wnt signaling plays a central role for coordinated cell polarization and directed migration in metazoan development. While spatiotemporally restricted activation of non-canonical Wnt-signaling drives cell polarization in epithelial tissues, it remains unclear whether such instructive activity is also critical for directed mesenchymal cell migration. Here, we developed a light-activated version of the non-canonical Wnt receptor Frizzled 7 (Fz7) to analyze how restricted activation of non-canonical Wnt signaling affects directed anterior axial mesendoderm (prechordal plate, ppl) cell migration within the zebrafish gastrula. We found that Fz7 signaling is required for ppl cell protrusion formation and migration and that spatiotemporally restricted ectopic activation is capable of redirecting their migration. Finally, we show that uniform activation of Fz7 signaling in ppl cells fully rescues defective directed cell migration in fz7 mutant embryos. Together, our findings reveal that in contrast to the situation in epithelial cells, non-canonical Wnt signaling functions permissively rather than instructively in directed mesenchymal cell migration during gastrulation.
Collapse
Affiliation(s)
- Daniel Čapek
- Institute of Science and Technology AustriaKlosterneuburgAustria
| | - Michael Smutny
- Institute of Science and Technology AustriaKlosterneuburgAustria
- Centre for Mechanochemical Cell Biology and Division of Biomedical Sciences, Warwick Medical SchoolUniversity of WarwickCoventryUnited Kingdom
| | - Alexandra-Madelaine Tichy
- Australian Regenerative Medicine Institute (ARMI), Faculty of Medicine, Nursing and Health SciencesMonash UniversityClaytonAustralia
- European Molecular Biology Laboratory Australia (EMBL Australia)Monash UniversityClaytonAustralia
| | - Maurizio Morri
- Institute of Science and Technology AustriaKlosterneuburgAustria
| | - Harald Janovjak
- Institute of Science and Technology AustriaKlosterneuburgAustria
- Australian Regenerative Medicine Institute (ARMI), Faculty of Medicine, Nursing and Health SciencesMonash UniversityClaytonAustralia
- European Molecular Biology Laboratory Australia (EMBL Australia)Monash UniversityClaytonAustralia
| | | |
Collapse
|
18
|
Analysis of novel domain-specific mutations in the zebrafish ndr2/cyclops gene generated using CRISPR-Cas9 RNPs. J Genet 2018. [DOI: 10.1007/s12041-018-1033-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
19
|
Turner AN, Andersen RS, Bookout IE, Brashear LN, Davis JC, Gahan DM, Davis JC, Gotham JP, Hijaz BA, Kaushik AS, Mcgill JB, Miller VL, Moseley ZP, Nowell CL, Patel RK, Rodgers MC, Patel RK, Shihab YA, Walker AP, Glover SR, Foster SD, Challa AK. Analysis of novel domain-specific mutations in the zebrafish ndr2/ cyclops gene generated using CRISPR-Cas9 RNPs. J Genet 2018. [PMID: 30555080 DOI: 10.1101/277715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Nodal-related protein (ndr2) is amember of the transforming growth factor type β superfamily of factors and is required for ventral midline patterning of the embryonic central nervous system in zebrafish. In humans, mutations in the gene encoding nodal cause holoprosencephaly and heterotaxy. Mutations in the ndr2 gene in the zebrafish (Danio rerio) lead to similar phenotypes, including loss of the medial floor plate, severe deficits in ventral forebrain development and cyclopia. Alleles of the ndr2 gene have been useful in studying patterning of ventral structures of the central nervous system. Fifteen different ndr2 alleles have been reported in zebrafish, of which eight were generated using chemical mutagenesis, four were radiation-induced and the remaining alleles were obtained via random insertion, gene targeting (TALEN) or unknown methods. Therefore, most mutation sites were random and could not be predicted a priori. Using the CRISPR-Cas9 system from Streptococcus pyogenes, we targeted distinct regions in all three exons of zebrafish ndr2 and observed cyclopia in the injected (G0) embryos.We show that the use of sgRNA-Cas9 ribonucleoprotein (RNP) complexes can cause penetrant cyclopic phenotypes in injected (G0) embryos. Targeted polymerase chain reaction amplicon analysis using Sanger sequencing showed that most of the alleles had small indels resulting in frameshifts. The sequence information correlates with the loss of ndr2 activity. In this study, we validate multiple CRISPR targets using an in vitro nuclease assay and in vivo analysis using embryos. We describe one specific mutant allele resulting in the loss of conserved terminal cysteine-coding sequences. This study is another demonstration of the utility of the CRISPR-Cas9 system in generating domain-specific mutations and provides further insights into the structure-function of the ndr2 gene.
Collapse
Affiliation(s)
- Ashley N Turner
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Ren X, Hamilton N, Müller F, Yamamoto Y. Cellular rearrangement of the prechordal plate contributes to eye degeneration in the cavefish. Dev Biol 2018; 441:221-234. [PMID: 30031755 DOI: 10.1016/j.ydbio.2018.07.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 07/16/2018] [Accepted: 07/18/2018] [Indexed: 12/23/2022]
Abstract
Astyanax mexicanus consists of two different populations: a sighted surface-dwelling form (surface fish) and a blind cave-dwelling form (cavefish). In the cavefish, embryonic expression of sonic hedgehog a (shha) in the prechordal plate is expanded towards the anterior midline, which has been shown to contribute to cavefish specific traits such as eye degeneration, enhanced feeding apparatus, and specialized brain anatomy. However, it is not clear how this expanded expression is achieved and which signaling pathways are involved. Nodal signaling has a crucial role for expression of shh and formation of the prechordal plate. In this study, we report increased expression of prechordal plate marker genes, nodal-related 2 (ndr2) and goosecoid (gsc) in cavefish embryos at the tailbud stage. To investigate whether Nodal signaling is responsible for the anterior expansion of the prechordal plate, we used an inhibitor of Nodal signaling and showed a decreased anterior expansion of the prechordal plate and increased pax6 expression in the anterior midline in treated cavefish embryos. Later in development, the lens and optic cup of treated embryos were significantly larger than untreated embryos. Conversely, increasing Nodal signaling in the surface fish embryo resulted in the expansion of anterior prechordal plate and reduction of pax6 expression in the anterior neural plate together with the formation of small lenses and optic cups later in development. These results confirmed that Nodal signaling has a crucial role for the anterior expansion of the prechordal plate and plays a significant role in cavefish eye development. We showed that the anterior expansion of the prechordal plate was not due to increased total cell number, suggesting the expansion is achieved by changes in cellular distribution in the prechordal plate. In addition, the distribution of presumptive prechordal plate cells in Spemann's organiser was also altered in the cavefish. These results suggested that changes in the cellular arrangement of Spemann's organiser in early gastrulae could have an essential role in the anterior expansion of the prechordal plate contributing to eye degeneration in the cavefish.
Collapse
Affiliation(s)
- Xiaoyun Ren
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Noémie Hamilton
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Ferenc Müller
- Institute of Cancer and Genomics Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Yoshiyuki Yamamoto
- Department of Cell and Developmental Biology, University College London, London, United Kingdom.
| |
Collapse
|
21
|
Abstract
TGF-β family ligands function in inducing and patterning many tissues of the early vertebrate embryonic body plan. Nodal signaling is essential for the specification of mesendodermal tissues and the concurrent cellular movements of gastrulation. Bone morphogenetic protein (BMP) signaling patterns tissues along the dorsal-ventral axis and simultaneously directs the cell movements of convergence and extension. After gastrulation, a second wave of Nodal signaling breaks the symmetry between the left and right sides of the embryo. During these processes, elaborate regulatory feedback between TGF-β ligands and their antagonists direct the proper specification and patterning of embryonic tissues. In this review, we summarize the current knowledge of the function and regulation of TGF-β family signaling in these processes. Although we cover principles that are involved in the development of all vertebrate embryos, we focus specifically on three popular model organisms: the mouse Mus musculus, the African clawed frog of the genus Xenopus, and the zebrafish Danio rerio, highlighting the similarities and differences between these species.
Collapse
Affiliation(s)
- Joseph Zinski
- University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104-6058
| | - Benjamin Tajer
- University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104-6058
| | - Mary C Mullins
- University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104-6058
| |
Collapse
|
22
|
Roessler E, Hu P, Muenke M. Holoprosencephaly in the genomics era. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2018; 178:165-174. [PMID: 29770992 DOI: 10.1002/ajmg.c.31615] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 04/06/2018] [Accepted: 04/11/2018] [Indexed: 01/08/2023]
Abstract
Holoprosencephaly (HPE) is the direct consequence of specific genetic and/or environmental insults interrupting the midline specification of the nascent forebrain. Such disturbances can lead to a broad range of phenotypic consequences for the brain and face in humans. This malformation sequence is remarkably common in utero (1 in 250 human fetuses), but 97% typically do not survive to birth. The precise molecular pathogenesis of HPE in these early human embryos remains largely unknown. Here, we outline our current understanding of the principal driving factors leading to HPE pathologies and elaborate our multifactorial integrated genomics approach. Overall, our understanding of the pathogenesis continues to become simpler, rather than more complicated. Genomic technologies now provide unprecedented insight into disease-associated variation, including the overall extent of genetic interactions (coding and noncoding) predicted to explain divergent phenotypes.
Collapse
Affiliation(s)
- Erich Roessler
- Medical Genetics Branch, National Human, Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Ping Hu
- Medical Genetics Branch, National Human, Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Maximilian Muenke
- Medical Genetics Branch, National Human, Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| |
Collapse
|
23
|
Wei S, Wang Q. Molecular regulation of Nodal signaling during mesendoderm formation. Acta Biochim Biophys Sin (Shanghai) 2018; 50:74-81. [PMID: 29206913 DOI: 10.1093/abbs/gmx128] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 11/09/2017] [Indexed: 01/17/2023] Open
Abstract
One of the most important events during vertebrate embryogenesis is the formation or specification of the three germ layers, endoderm, mesoderm, and ectoderm. After a series of rapid cleavages, embryos form the mesendoderm and ectoderm during late blastulation and early gastrulation. The mesendoderm then further differentiates into the mesoderm and endoderm. Nodal, a member of the transforming growth factor β (TGF-β) superfamily, plays a pivotal role in mesendoderm formation by regulating the expression of a number of critical transcription factors, including Mix-like, GATA, Sox, and Fox. Because the Nodal signal transduction pathway is well-characterized, increasing effort has been made to delineate the spatiotemporal modulation of Nodal signaling during embryonic development. In this review, we summarize the recent progress delineating molecular regulation of Nodal signal intensity and duration during mesendoderm formation.
Collapse
Affiliation(s)
- Shi Wei
- The State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou 510060, China
| | - Qiang Wang
- State Key Laboratory of Membrane Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| |
Collapse
|
24
|
Tadjuidje E, Kofron M, Mir A, Wylie C, Heasman J, Cha SW. Nodal signalling in Xenopus: the role of Xnr5 in left/right asymmetry and heart development. Open Biol 2017; 6:rsob.150187. [PMID: 27488374 PMCID: PMC5008007 DOI: 10.1098/rsob.150187] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 07/01/2016] [Indexed: 01/05/2023] Open
Abstract
Nodal class TGF-β signalling molecules play essential roles in establishing the vertebrate body plan. In all vertebrates, nodal family members have specific waves of expression required for tissue specification and axis formation. In Xenopus laevis, six nodal genes are expressed before gastrulation, raising the question of whether they have specific roles or act redundantly with each other. Here, we examine the role of Xnr5. We find it acts at the late blastula stage as a mesoderm inducer and repressor of ectodermal gene expression, a role it shares with Vg1. However, unlike Vg1, Xnr5 depletion reduces the expression of the nodal family member xnr1 at the gastrula stage. It is also required for left/right laterality by controlling the expression of the laterality genes xnr1, antivin (lefty) and pitx2 at the tailbud stage. In Xnr5-depleted embryos, the heart field is established normally, but symmetrical reduction in Xnr5 levels causes a severely stunted midline heart, first evidenced by a reduction in cardiac troponin mRNA levels, while left-sided reduction leads to randomization of the left/right axis. This work identifies Xnr5 as the earliest step in the signalling pathway establishing normal heart laterality in Xenopus.
Collapse
Affiliation(s)
- Emmanuel Tadjuidje
- Department of Biological Sciences, Alabama State University, 1627 Hall Street, Montgomery, AL 36101, USA
| | - Matthew Kofron
- Cincinnati Children's Research Foundation, 3333 Burnet Avenue, Cincinnati, OH 45229, USA
| | - Adnan Mir
- Cincinnati Children's Research Foundation, 3333 Burnet Avenue, Cincinnati, OH 45229, USA
| | - Christopher Wylie
- Cincinnati Children's Research Foundation, 3333 Burnet Avenue, Cincinnati, OH 45229, USA
| | - Janet Heasman
- Cincinnati Children's Research Foundation, 3333 Burnet Avenue, Cincinnati, OH 45229, USA
| | - Sang-Wook Cha
- Cincinnati Children's Research Foundation, 3333 Burnet Avenue, Cincinnati, OH 45229, USA
| |
Collapse
|
25
|
Bisgrove BW, Su YC, Yost HJ. Maternal Gdf3 is an obligatory cofactor in Nodal signaling for embryonic axis formation in zebrafish. eLife 2017; 6:28534. [PMID: 29140249 PMCID: PMC5745076 DOI: 10.7554/elife.28534] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 11/10/2017] [Indexed: 11/18/2022] Open
Abstract
Zebrafish Gdf3 (Dvr1) is a member of the TGFβ superfamily of cell signaling ligands that includes Xenopus Vg1 and mammalian Gdf1/3. Surprisingly, engineered homozygous mutants in zebrafish have no apparent phenotype. Elimination of Gdf3 in oocytes of maternal-zygotic mutants results in embryonic lethality that can be fully rescued with gdf3 RNA, demonstrating that Gdf3 is required only early in development, beyond which mutants are viable and fertile. Gdf3 mutants are refractory to Nodal ligands and Nodal repressor Lefty1. Signaling driven by TGFβ ligand Activin and constitutively active receptors Alk4 and Alk2 remain intact in gdf3 mutants, indicating that Gdf3 functions at the same pathway step as Nodal. Targeting gdf3 and ndr2 RNA to specific lineages indicates that exogenous gdf3 is able to fully rescue mutants only when co-expressed with endogenous Nodal. Together, these findings demonstrate that Gdf3 is an essential cofactor of Nodal signaling during establishment of the embryonic axis. All vertebrates – animals with backbones like fish and humans – have body plans with three clear axes: head-to-tail, back-to-front and left-to-right. Animals lay down these plans as embryos, when signaling molecules bind to receptors on the surface of their cells. These signaling molecules include related proteins called “Nodal” and “Growth and Differentiation Factors”. However, there has been much debate in the field of developmental biology about whether these proteins work together or independently during the early development of vertebrates. Zebrafish are often used to study animal development, and Bisgrove et al. decided to test whether these fish need a Growth and Differentiation Factor known as Gdf3 by deleting it using genome editing. It turns out that zebrafish can survive and develop as normal without the gene for Gdf3, just as long as their mothers still had a working copy of the gene. Yet, when the offspring of mutant females did not inherit the instructions to make Gdf3 from their mothers, they died within a couple of days. This was true even if the offspring inherited a working copy of the gene from their fathers. Bisgrove et al. then went on to show that embryos from a mutant mother could be saved with an injection of short-lived RNA molecules that include the instructions to make some Gdf3 proteins. The injected mutant embryos could live to adulthood. This shows that Gdf3 is only needed during the embryo’s early development. Further experiments suggested that Gdf3 does cannot activate its receptors on its own. Instead, it is likely that Gdf3 interacts with Nodal to form a two-protein complex that activates the receptors. Two other groups of researchers have independently reported similar findings. Mutations affecting proteins very similar to Gdf3 have been found in people with congenital heart defects. By revealing the interaction between Gdf3 and Nodal, these new findings could help scientists to understand the genetic causes of this condition in more detail. Further studies using the mutant zebrafish could also be used to explore the causes of other developmental diseases.
Collapse
Affiliation(s)
- Brent W Bisgrove
- Molecular Medicine Program, Eccles Institute of Human Genetics, University of Utah, Salt Lake City, United States
| | - Yi-Chu Su
- Molecular Medicine Program, Eccles Institute of Human Genetics, University of Utah, Salt Lake City, United States
| | - H Joseph Yost
- Molecular Medicine Program, Eccles Institute of Human Genetics, University of Utah, Salt Lake City, United States
| |
Collapse
|
26
|
Pelliccia JL, Jindal GA, Burdine RD. Gdf3 is required for robust Nodal signaling during germ layer formation and left-right patterning. eLife 2017; 6:28635. [PMID: 29140250 PMCID: PMC5745080 DOI: 10.7554/elife.28635] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 11/07/2017] [Indexed: 12/12/2022] Open
Abstract
Vertebrate embryonic patterning depends on signaling from Nodal, a TGFβ superfamily member. There are three Nodal orthologs in zebrafish; southpaw directs left-right asymmetries, while squint and cyclops function earlier to pattern mesendoderm. TGFβ member Vg1 is implicated in mesoderm formation but the role of the zebrafish ortholog, Growth differentiation factor 3 (Gdf3), has not been fully explored. We show that zygotic expression of gdf3 is dispensable for embryonic development, while maternally deposited gdf3 is required for mesendoderm formation and dorsal-ventral patterning. We further show that Gdf3 can affect left-right patterning at multiple stages, including proper development of regional cell morphology in Kupffer’s vesicle and the establishment of southpaw expression in the lateral plate mesoderm. Collectively, our data indicate that gdf3 is critical for robust Nodal signaling at multiple stages in zebrafish embryonic development.
Collapse
Affiliation(s)
- Jose L Pelliccia
- Department of Molecular Biology, Princeton University, Princeton, United States
| | - Granton A Jindal
- Department of Molecular Biology, Princeton University, Princeton, United States.,Department of Chemical and Biological Engineering, Princeton University, Princeton, United States.,The Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, United States
| | - Rebecca D Burdine
- Department of Molecular Biology, Princeton University, Princeton, United States
| |
Collapse
|
27
|
Roberson S, Halpern ME. Development and connectivity of the habenular nuclei. Semin Cell Dev Biol 2017; 78:107-115. [PMID: 29107475 PMCID: PMC5920772 DOI: 10.1016/j.semcdb.2017.10.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 10/09/2017] [Indexed: 10/17/2022]
Abstract
Accumulating evidence has reinforced that the habenular region of the vertebrate dorsal forebrain is an essential integrating center, and a region strongly implicated in neurological disorders and addiction. Despite the important and diverse neuromodulatory roles the habenular nuclei play, their development has been understudied. The emphasis of this review is on the dorsal habenular nuclei of zebrafish, homologous to the medial nuclei of mammals, as recent work has revealed new information about the signaling pathways that regulate their formation. Additionally, the zebrafish dorsal habenulae have become a valuable model for probing how left-right differences are established in a vertebrate brain. Sonic hedgehog, fibroblast growth factors and Wingless-INT proteins are all involved in the generation of progenitor cells and ultimately, along with Notch signaling, influence habenular neurogenesis and left-right asymmetry. Intriguingly, a genetic network has emerged that leads to the differentiation of dorsal habenular neurons and, through localized chemokine signaling, directs the posterior outgrowth of their newly emerging axons towards their postsynaptic target, the midbrain interpeduncular nucleus.
Collapse
Affiliation(s)
- Sara Roberson
- Carnegie Institution for Science, Department of Embryology, 3520 San Martin Drive Baltimore, MD 21218, USA; Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Marnie E Halpern
- Carnegie Institution for Science, Department of Embryology, 3520 San Martin Drive Baltimore, MD 21218, USA; Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA.
| |
Collapse
|
28
|
Meyers EA, Kessler JA. TGF-β Family Signaling in Neural and Neuronal Differentiation, Development, and Function. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a022244. [PMID: 28130363 DOI: 10.1101/cshperspect.a022244] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Signaling by the transforming growth factor β (TGF-β) family is necessary for proper neural development and function throughout life. Sequential waves of activation, inhibition, and reactivation of TGF-β family members regulate numerous elements of the nervous system from the earliest stages of embryogenesis through adulthood. This review discusses the expression, regulation, and function of TGF-β family members in the central nervous system at various developmental stages, beginning with induction and patterning of the nervous system to their importance in the adult as modulators of inflammatory response and involvement in degenerative diseases.
Collapse
Affiliation(s)
- Emily A Meyers
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - John A Kessler
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| |
Collapse
|
29
|
Danesin C, Soula C. Moving the Shh Source over Time: What Impact on Neural Cell Diversification in the Developing Spinal Cord? J Dev Biol 2017; 5:jdb5020004. [PMID: 29615562 PMCID: PMC5831764 DOI: 10.3390/jdb5020004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 03/29/2017] [Accepted: 04/06/2017] [Indexed: 12/18/2022] Open
Abstract
A substantial amount of data has highlighted the crucial influence of Shh signalling on the generation of diverse classes of neurons and glial cells throughout the developing central nervous system. A critical step leading to this diversity is the establishment of distinct neural progenitor cell domains during the process of pattern formation. The forming spinal cord, in particular, has served as an excellent model to unravel how progenitor cells respond to Shh to produce the appropriate pattern. In recent years, considerable advances have been made in our understanding of important parameters that control the temporal and spatial interpretation of the morphogen signal at the level of Shh-receiving progenitor cells. Although less studied, the identity and position of Shh source cells also undergo significant changes over time, raising the question of how moving the Shh source contributes to cell diversification in response to the morphogen. Here, we focus on the dynamics of Shh-producing cells and discuss specific roles for these time-variant Shh sources with regard to the temporal events occurring in the receiving field.
Collapse
Affiliation(s)
- Cathy Danesin
- Centre de Biologie du Développement (CBD) CNRS/UPS, Centre de Biologie Intégrative (CBI), Université de Toulouse, 31520 Toulouse, France.
| | - Cathy Soula
- Centre de Biologie du Développement (CBD) CNRS/UPS, Centre de Biologie Intégrative (CBI), Université de Toulouse, 31520 Toulouse, France.
| |
Collapse
|
30
|
Smutny M, Ákos Z, Grigolon S, Shamipour S, Ruprecht V, Čapek D, Behrndt M, Papusheva E, Tada M, Hof B, Vicsek T, Salbreux G, Heisenberg CP. Friction forces position the neural anlage. Nat Cell Biol 2017; 19:306-317. [PMID: 28346437 PMCID: PMC5635970 DOI: 10.1038/ncb3492] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 02/17/2017] [Indexed: 12/23/2022]
Abstract
During embryonic development, mechanical forces are essential for cellular rearrangements driving tissue morphogenesis. Here, we show that in the early zebrafish embryo, friction forces are generated at the interface between anterior axial mesoderm (prechordal plate, ppl) progenitors migrating towards the animal pole and neurectoderm progenitors moving in the opposite direction towards the vegetal pole of the embryo. These friction forces lead to global rearrangement of cells within the neurectoderm and determine the position of the neural anlage. Using a combination of experiments and simulations, we show that this process depends on hydrodynamic coupling between neurectoderm and ppl as a result of E-cadherin-mediated adhesion between those tissues. Our data thus establish the emergence of friction forces at the interface between moving tissues as a critical force-generating process shaping the embryo.
Collapse
Affiliation(s)
- Michael Smutny
- Institute of Science and Technology Austria, Am Campus 1,
A-3400 Klosterneuburg, Austria
| | - Zsuzsa Ákos
- Department of Biological Physics, Eötvös
University, Pázmány Péter sétány 1A, Budapest
H-1117, Hungary
| | - Silvia Grigolon
- The Francis Crick Institute, 1 Midland Road, London NW1
1AT, UK
| | - Shayan Shamipour
- Institute of Science and Technology Austria, Am Campus 1,
A-3400 Klosterneuburg, Austria
| | - Verena Ruprecht
- Centre for Genomic Regulation (CRG), The Barcelona
Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain
- Universitat Pompeu Fabra (UPF), 08003, Barcelona,
Spain
| | - Daniel Čapek
- Institute of Science and Technology Austria, Am Campus 1,
A-3400 Klosterneuburg, Austria
| | - Martin Behrndt
- Institute of Science and Technology Austria, Am Campus 1,
A-3400 Klosterneuburg, Austria
| | - Ekaterina Papusheva
- Institute of Science and Technology Austria, Am Campus 1,
A-3400 Klosterneuburg, Austria
| | - Masazumi Tada
- Department of Cell and Developmental Biology, University
College London, Gower Street, London, WC1E 6BT, UK
| | - Björn Hof
- Institute of Science and Technology Austria, Am Campus 1,
A-3400 Klosterneuburg, Austria
| | - Tamás Vicsek
- Department of Biological Physics, Eötvös
University, Pázmány Péter sétány 1A, Budapest
H-1117, Hungary
| | | | | |
Collapse
|
31
|
Chen J, Xia L, Bruchas MR, Solnica-Krezel L. Imaging early embryonic calcium activity with GCaMP6s transgenic zebrafish. Dev Biol 2017; 430:385-396. [PMID: 28322738 PMCID: PMC5835148 DOI: 10.1016/j.ydbio.2017.03.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 01/12/2017] [Accepted: 03/11/2017] [Indexed: 12/02/2022]
Abstract
Intracellular Ca2+ signaling regulates cellular activities during embryogenesis and in adult organisms. We generated stable Tg[βactin2:GCaMP6s]stl351 and Tg[ubi:GCaMP6s]stl352 transgenic lines that combine the ubiquitously-expressed Ca2+ indicator GCaMP6s with the transparent characteristics of zebrafish embryos to achieve superior in vivo Ca2+ imaging. Using the Tg[βactin2:GCaMP6s]stl351 line featuring strong GCaMP6s expression from cleavage through gastrula stages, we detected higher frequency of Ca2+ transients in the superficial blastomeres during the blastula stages preceding the midblastula transition. Additionally, GCaMP6s also revealed that dorsal-biased Ca2+ signaling that follows the midblastula transition persisted longer during gastrulation, compared with earlier studies. We observed that dorsal-biased Ca2+ signaling is diminished in ventralized ichabod/β-catenin2 mutant embryos and ectopically induced in embryos dorsalized by excess β-catenin. During gastrulation, we directly visualized Ca2+ signaling in the dorsal forerunner cells, which form in a Nodal signaling dependent manner and later give rise to the laterality organ. We found that excess Nodal increases the number and the duration of Ca2+ transients specifically in the dorsal forerunner cells. The GCaMP6s transgenic lines described here enable unprecedented visualization of dynamic Ca2+ events from embryogenesis through adulthood, augmenting the zebrafish toolbox.
Collapse
Affiliation(s)
- Jiakun Chen
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Li Xia
- Department of Anesthesiology, Division of Basic Research, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Biomedical Engineering, Washington University in St. Louis, St Louis, MO, 63105, USA
| | - Michael R Bruchas
- Department of Anesthesiology, Division of Basic Research, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Biomedical Engineering, Washington University in St. Louis, St Louis, MO, 63105, USA; Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, USA
| | - Lilianna Solnica-Krezel
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA.
| |
Collapse
|
32
|
Tseng WC, Munisha M, Gutierrez JB, Dougan ST. Establishment of the Vertebrate Germ Layers. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 953:307-381. [PMID: 27975275 DOI: 10.1007/978-3-319-46095-6_7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The process of germ layer formation is a universal feature of animal development. The germ layers separate the cells that produce the internal organs and tissues from those that produce the nervous system and outer tissues. Their discovery in the early nineteenth century transformed embryology from a purely descriptive field into a rigorous scientific discipline, in which hypotheses could be tested by observation and experimentation. By systematically addressing the questions of how the germ layers are formed and how they generate overall body plan, scientists have made fundamental contributions to the fields of evolution, cell signaling, morphogenesis, and stem cell biology. At each step, this work was advanced by the development of innovative methods of observing cell behavior in vivo and in culture. Here, we take an historical approach to describe our current understanding of vertebrate germ layer formation as it relates to the long-standing questions of developmental biology. By comparing how germ layers form in distantly related vertebrate species, we find that highly conserved molecular pathways can be adapted to perform the same function in dramatically different embryonic environments.
Collapse
Affiliation(s)
- Wei-Chia Tseng
- Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Mumingjiang Munisha
- Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Juan B Gutierrez
- Department of Mathematics, University of Georgia, Athens, GA, 30602, USA.,Institute of Bioinformatics, University of Georgia, Athens, GA, 30602, USA
| | - Scott T Dougan
- Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA.
| |
Collapse
|
33
|
Duboué ER, Halpern ME. Genetic and Transgenic Approaches to Study Zebrafish Brain Asymmetry and Lateralized Behavior. LATERALIZED BRAIN FUNCTIONS 2017. [DOI: 10.1007/978-1-4939-6725-4_17] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
|
34
|
Houston DW. Vertebrate Axial Patterning: From Egg to Asymmetry. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 953:209-306. [PMID: 27975274 PMCID: PMC6550305 DOI: 10.1007/978-3-319-46095-6_6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The emergence of the bilateral embryonic body axis from a symmetrical egg has been a long-standing question in developmental biology. Historical and modern experiments point to an initial symmetry-breaking event leading to localized Wnt and Nodal growth factor signaling and subsequent induction and formation of a self-regulating dorsal "organizer." This organizer forms at the site of notochord cell internalization and expresses primarily Bone Morphogenetic Protein (BMP) growth factor antagonists that establish a spatiotemporal gradient of BMP signaling across the embryo, directing initial cell differentiation and morphogenesis. Although the basics of this model have been known for some time, many of the molecular and cellular details have only recently been elucidated and the extent that these events remain conserved throughout vertebrate evolution remains unclear. This chapter summarizes historical perspectives as well as recent molecular and genetic advances regarding: (1) the mechanisms that regulate symmetry-breaking in the vertebrate egg and early embryo, (2) the pathways that are activated by these events, in particular the Wnt pathway, and the role of these pathways in the formation and function of the organizer, and (3) how these pathways also mediate anteroposterior patterning and axial morphogenesis. Emphasis is placed on comparative aspects of the egg-to-embryo transition across vertebrates and their evolution. The future prospects for work regarding self-organization and gene regulatory networks in the context of early axis formation are also discussed.
Collapse
Affiliation(s)
- Douglas W Houston
- Department of Biology, The University of Iowa, 257 BB, Iowa City, IA, 52242, USA.
| |
Collapse
|
35
|
Sako K, Pradhan SJ, Barone V, Inglés-Prieto Á, Müller P, Ruprecht V, Čapek D, Galande S, Janovjak H, Heisenberg CP. Optogenetic Control of Nodal Signaling Reveals a Temporal Pattern of Nodal Signaling Regulating Cell Fate Specification during Gastrulation. Cell Rep 2016; 16:866-77. [PMID: 27396324 DOI: 10.1016/j.celrep.2016.06.036] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 04/21/2016] [Accepted: 06/05/2016] [Indexed: 01/20/2023] Open
Abstract
During metazoan development, the temporal pattern of morphogen signaling is critical for organizing cell fates in space and time. Yet, tools for temporally controlling morphogen signaling within the embryo are still scarce. Here, we developed a photoactivatable Nodal receptor to determine how the temporal pattern of Nodal signaling affects cell fate specification during zebrafish gastrulation. By using this receptor to manipulate the duration of Nodal signaling in vivo by light, we show that extended Nodal signaling within the organizer promotes prechordal plate specification and suppresses endoderm differentiation. Endoderm differentiation is suppressed by extended Nodal signaling inducing expression of the transcriptional repressor goosecoid (gsc) in prechordal plate progenitors, which in turn restrains Nodal signaling from upregulating the endoderm differentiation gene sox17 within these cells. Thus, optogenetic manipulation of Nodal signaling identifies a critical role of Nodal signaling duration for organizer cell fate specification during gastrulation.
Collapse
Affiliation(s)
- Keisuke Sako
- Laboratory of Developmental Biology, Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
| | - Saurabh J Pradhan
- Indian Institute of Science, Education and Research, Pune 411008, India
| | - Vanessa Barone
- Laboratory of Developmental Biology, Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
| | - Álvaro Inglés-Prieto
- Laboratory of Synthetic Physiology, Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
| | - Patrick Müller
- Friedrich Miescher Laboratory of the Max Planck Society, 72076 Tübingen, Germany
| | - Verena Ruprecht
- Laboratory of Developmental Biology, Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
| | - Daniel Čapek
- Laboratory of Developmental Biology, Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
| | - Sanjeev Galande
- Indian Institute of Science, Education and Research, Pune 411008, India
| | - Harald Janovjak
- Laboratory of Synthetic Physiology, Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria.
| | - Carl-Philipp Heisenberg
- Laboratory of Developmental Biology, Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria.
| |
Collapse
|
36
|
Wang Y, Wang X, Wohland T, Sampath K. Extracellular interactions and ligand degradation shape the nodal morphogen gradient. eLife 2016; 5. [PMID: 27101364 PMCID: PMC4887204 DOI: 10.7554/elife.13879] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 04/20/2016] [Indexed: 01/19/2023] Open
Abstract
The correct distribution and activity of secreted signaling proteins called morphogens is required for many developmental processes. Nodal morphogens play critical roles in embryonic axis formation in many organisms. Models proposed to generate the Nodal gradient include diffusivity, ligand processing, and a temporal activation window. But how the Nodal morphogen gradient forms in vivo remains unclear. Here, we have measured in vivo for the first time, the binding affinity of Nodal ligands to their major cell surface receptor, Acvr2b, and to the Nodal inhibitor, Lefty, by fluorescence cross-correlation spectroscopy. We examined the diffusion coefficient of Nodal ligands and Lefty inhibitors in live zebrafish embryos by fluorescence correlation spectroscopy. We also investigated the contribution of ligand degradation to the Nodal gradient. We show that ligand clearance via degradation shapes the Nodal gradient and correlates with its signaling range. By computational simulations of gradient formation, we demonstrate that diffusivity, extra-cellular interactions, and selective ligand destruction collectively shape the Nodal morphogen gradient. DOI:http://dx.doi.org/10.7554/eLife.13879.001 Animals develop from a single fertilized egg cell into multicellular organisms. This process requires chemical signals called “morphogens” that instruct the cells how to behave during development. The morphogens move across cells and tissues to form gradients of the signal. Cells then respond in different ways depending on how much of the signal they receive. This, in turn, depends on several factors: first, how quickly or slowly the signal moves; second, how well the morphogen binds to responding cells and other molecules in its path; and third, how much signal is lost or destroyed during the movement. Many researchers study morphogen gradients in the transparent zebrafish, since it grows quickly and it is easy to see developmental changes. However, until now it was not fully clear how the well-known morphogen called Nodal moves in live zebrafish as they develop. Wang, Wang et al. have now investigated how well Nodal signals bind to the surface of cells that receive the signal and to a molecule called “Lefty”, which is present in the same path and interferes with Nodal signals. Advanced techniques called fluorescence correlation and cross-correlation spectroscopy were used to measure Nodal signals at the level of single molecules in growing zebrafish. The experiments gave insights into how far Nodal signals move and remain active. The results showed that, in addition to Nodal diffusing and binding to receiving cells, one of the most important factors determining how far and quickly Nodal moves is its inactivation and destruction. Lastly, Wang, Wang et al. built computational models to test their observations from live zebrafish. The current work was based on forcing zebrafish to produce molecules including Nodal at locations within the fish that normally do not make them. Therefore future experiments will aim to examine these molecules and their interactions when they are produced at their normal locations in the animal over time. DOI:http://dx.doi.org/10.7554/eLife.13879.002
Collapse
Affiliation(s)
- Yin Wang
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom.,Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Xi Wang
- Department of Chemistry, Centre for Bioimaging Sciences, National University of Singapore, Singapore, Singapore
| | - Thorsten Wohland
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore.,Department of Chemistry, Centre for Bioimaging Sciences, National University of Singapore, Singapore, Singapore
| | - Karuna Sampath
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| |
Collapse
|
37
|
Deshwar AR, Chng SC, Ho L, Reversade B, Scott IC. The Apelin receptor enhances Nodal/TGFβ signaling to ensure proper cardiac development. eLife 2016; 5. [PMID: 27077952 PMCID: PMC4859801 DOI: 10.7554/elife.13758] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Accepted: 04/11/2016] [Indexed: 01/07/2023] Open
Abstract
The Apelin receptor (Aplnr) is essential for heart development, controlling the early migration of cardiac progenitors. Here we demonstrate that in zebrafish Aplnr modulates Nodal/TGFβ signaling, a key pathway essential for mesendoderm induction and migration. Loss of Aplnr function leads to a reduction in Nodal target gene expression whereas activation of Aplnr by a non-peptide agonist increases the expression of these same targets. Furthermore, loss of Aplnr results in a delay in the expression of the cardiogenic transcription factors mespaa/ab. Elevating Nodal levels in aplnra/b morphant and double mutant embryos is sufficient to rescue cardiac differentiation defects. We demonstrate that loss of Aplnr attenuates the activity of a point source of Nodal ligands Squint and Cyclops in a non-cell autonomous manner. Our results favour a model in which Aplnr is required to fine-tune Nodal output, acting as a specific rheostat for the Nodal/TGFβ pathway during the earliest stages of cardiogenesis. DOI:http://dx.doi.org/10.7554/eLife.13758.001 In one of the first events that happens as an embryo develops, cells become the different stem cell populations that form the body’s organs. So what makes a cell become one stem cell type rather than another? In the case of the heart, the first important event is the activity of a signaling pathway called the Nodal/TGFβ pathway. Nodal signaling can drive cells to become many different stem cell types depending on its level of activity. Many different levels of regulation fine-tune Nodal signaling to produce these activity thresholds. Zebrafish that have a mutation in the gene that encodes a protein called the Apelin receptor have no heart. The loss of this receptor interferes with how heart stem cells (called cardiac progenitors) are made and how they move to where heart development occurs. Deshwar et al. have now studied mutant zebrafish in order to investigate how the Apelin receptor influences early heart development. This revealed that Nodal signaling levels are slightly lower in the mutant zebrafish embryos than in normal fish at the time when Nodal activity induces cardiac progenitors to form. When Nodal activity is experimentally boosted in zebrafish that lack the Apelin receptor, they become able to develop hearts. Deshwar et al. also found that the Apelin receptor does not work in cells that produce or receive Nodal signals. This suggests that the Apelin receptor modulates Nodal signaling levels by acting in cells that lie between the cells that release Nodal signals and the cardiac progenitors. An important question for future work to address is how this modulation works. As Nodal is a key determinant of many cell types in developing embryos, learning how Apelin receptors regulate its activity could help researchers to derive specific cell types from cultured stem cells for use in regenerative medicine. DOI:http://dx.doi.org/10.7554/eLife.13758.002
Collapse
Affiliation(s)
- Ashish R Deshwar
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Serene C Chng
- Institute of Medical Biology, A*STAR, Singapore, Singapore
| | - Lena Ho
- Institute of Medical Biology, A*STAR, Singapore, Singapore
| | - Bruno Reversade
- Institute of Medical Biology, A*STAR, Singapore, Singapore.,Institute of Molecular and Cellular Biology, A*STAR, Singapore, Singapore.,Department of Paediatrics, School of Medicine, National University of Singapore, , Singapore
| | - Ian C Scott
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Canada.,Heart and Stroke/Richard Lewar Centre of Excellence in Cardiovascular Research, University of Toronto, Toronto, Canada
| |
Collapse
|
38
|
Gonsar N, Coughlin A, Clay-Wright JA, Borg BR, Kindt LM, Liang JO. Temporal and spatial requirements for Nodal-induced anterior mesendoderm and mesoderm in anterior neurulation. Genesis 2016; 54:3-18. [PMID: 26528772 DOI: 10.1002/dvg.22908] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 10/29/2015] [Accepted: 10/30/2015] [Indexed: 01/28/2023]
Abstract
Zebrafish with defective Nodal signaling have a phenotype analogous to the fatal human birth defect anencephaly, which is caused by an open anterior neural tube. Previous work in our laboratory found that anterior open neural tube phenotypes in Nodal signaling mutants were caused by lack of mesendodermal/mesodermal tissues. Defects in these mutants are already apparent at neural plate stage, before the neuroepithelium starts to fold into a tube. Consistent with this, we found that the requirement for Nodal signaling maps to mid-late blastula stages. This timing correlates with the timing of prechordal plate mesendoderm and anterior mesoderm induction, suggesting these tissues act to promote neurulation. To further identify tissues important for neurulation, we took advantage of the variable phenotypes in Nodal signaling-deficient sqt mutant and Lefty1-overexpressing embryos. Statistical analysis indicated a strong, positive correlation between a closed neural tube and presence of several mesendoderm/mesoderm-derived tissues (hatching glands, cephalic paraxial mesoderm, notochord, and head muscles). However, the neural tube was closed in a subset of embryos that lacked any one of these tissues. This suggests that several types of Nodal-induced mesendodermal/mesodermal precursors are competent to promote neurulation.
Collapse
Affiliation(s)
- Ngawang Gonsar
- Department of Biology, University of Minnesota Duluth, Duluth, MN.,Integrated Biosciences Graduate Program, University of Minnesota, Duluth, MN
| | - Alicia Coughlin
- Department of Biology, University of Minnesota Duluth, Duluth, MN.,Integrated Biosciences Graduate Program, University of Minnesota, Duluth, MN
| | | | - Bethanie R Borg
- Department of Biology, University of Minnesota Duluth, Duluth, MN
| | - Lexy M Kindt
- Department of Biology, University of Minnesota Duluth, Duluth, MN.,Integrated Biosciences Graduate Program, University of Minnesota, Duluth, MN
| | - Jennifer O Liang
- Department of Biology, University of Minnesota Duluth, Duluth, MN.,Integrated Biosciences Graduate Program, University of Minnesota, Duluth, MN
| |
Collapse
|
39
|
Ma P, Swartz MR, Kindt LM, Kangas AM, Liang JO. Temperature Sensitivity of Neural Tube Defects in Zoep Mutants. Zebrafish 2015; 12:448-56. [PMID: 26366681 DOI: 10.1089/zeb.2015.1113] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Neural tube defects (NTD) occur when the flat neural plate epithelium fails to fold into the neural tube, the precursor to the brain and spinal cord. Squint (Sqt/Ndr1), a Nodal ligand, and One-eyed pinhead (Oep), a component of the Nodal receptor, are required for anterior neural tube closure in zebrafish. The NTD in sqt and Zoep mutants are incompletely penetrant. The penetrance of several defects in sqt mutants increases upon heat or cold shock. In this project, undergraduate students tested whether temperature influences the Zoep open neural tube phenotype. Single pairs of adults were spawned at 28.5°C, the normal temperature for zebrafish, and one half of the resulting embryos were moved to 34°C at different developmental time points. Analysis of variance indicated temperature and clutch/genetic background significantly contributed to the penetrance of the open neural tube phenotype. Heat shock affected the embryos only at or before the midblastula stage. Many factors, including temperature changes in the mother, nutrition, and genetic background, contribute to NTD in humans. Thus, sqt and Zoep mutants may serve as valuable models for studying the interactions between genetics and the environment during neurulation.
Collapse
Affiliation(s)
- Phyo Ma
- 1 Department of Biology, University of Minnesota Duluth , Duluth, Minnesota
| | - Morgan R Swartz
- 1 Department of Biology, University of Minnesota Duluth , Duluth, Minnesota
| | - Lexy M Kindt
- 1 Department of Biology, University of Minnesota Duluth , Duluth, Minnesota.,2 Integrated Biosciences Graduate Program, University of Minnesota , Duluth, Minnesota
| | - Ashley M Kangas
- 1 Department of Biology, University of Minnesota Duluth , Duluth, Minnesota
| | | |
Collapse
|
40
|
A Floor-Plate Extracellular Protein-Protein Interaction Screen Identifies Draxin as a Secreted Netrin-1 Antagonist. Cell Rep 2015; 12:694-708. [DOI: 10.1016/j.celrep.2015.06.047] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 04/28/2015] [Accepted: 06/11/2015] [Indexed: 11/20/2022] Open
|
41
|
Payumo AY, Walker WJ, McQuade LE, Yamazoe S, Chen JK. Optochemical dissection of T-box gene-dependent medial floor plate development. ACS Chem Biol 2015; 10:1466-75. [PMID: 25781211 DOI: 10.1021/cb5010178] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In addition to their cell-autonomous roles in mesoderm development, the zebrafish T-box transcription factors no tail a (ntla) and spadetail (spt/tbx16) are required for medial floor plate (MFP) formation. Posterior MFP cells are completely absent in zebrafish embryos lacking both Ntla and Spt function, and genetic mosaic analyses have shown that the two T-box genes promote MFP development in a non-cell-autonomous manner. On the basis of these observations, it has been proposed that Ntla/Spt-dependent mesoderm-derived signals are required for the induction of posterior but not anterior MFP cells. To investigate the mechanisms by which Ntla and Spt regulate MFP development, we have used photoactivatable caged morpholinos (cMOs) to silence these T-box genes with spatiotemporal control. We find that posterior MFP formation requires Ntla or Spt activity during early gastrulation, specifically in lateral margin-derived cells that converge toward the midline during epiboly and somitogenesis. Nodal signaling-dependent MFP specification is maintained in the absence of Ntla and Spt function; however, midline cells in ntla;spt morphants exhibit aberrant morphogenetic movements, resulting in their anterior mislocalization. Our findings indicate that Ntla and Spt do not differentially regulate MFP induction along the anterior-posterior axis; rather, the T-box genes act redundantly within margin-derived cells to promote the posterior extension of MFP progenitors.
Collapse
Affiliation(s)
- Alexander Y. Payumo
- Department of Chemical and Systems Biology, ‡Department of Developmental
Biology, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Whitney J. Walker
- Department of Chemical and Systems Biology, ‡Department of Developmental
Biology, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Lindsey E. McQuade
- Department of Chemical and Systems Biology, ‡Department of Developmental
Biology, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Sayumi Yamazoe
- Department of Chemical and Systems Biology, ‡Department of Developmental
Biology, Stanford University School of Medicine, Stanford, California 94305, United States
| | - James K. Chen
- Department of Chemical and Systems Biology, ‡Department of Developmental
Biology, Stanford University School of Medicine, Stanford, California 94305, United States
| |
Collapse
|
42
|
Tuazon FB, Mullins MC. Temporally coordinated signals progressively pattern the anteroposterior and dorsoventral body axes. Semin Cell Dev Biol 2015; 42:118-33. [PMID: 26123688 PMCID: PMC4562868 DOI: 10.1016/j.semcdb.2015.06.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 06/16/2015] [Indexed: 10/23/2022]
Abstract
The vertebrate body plan is established through the precise spatiotemporal coordination of morphogen signaling pathways that pattern the anteroposterior (AP) and dorsoventral (DV) axes. Patterning along the AP axis is directed by posteriorizing signals Wnt, fibroblast growth factor (FGF), Nodal, and retinoic acid (RA), while patterning along the DV axis is directed by bone morphogenetic proteins (BMP) ventralizing signals. This review addresses the current understanding of how Wnt, FGF, RA and BMP pattern distinct AP and DV cell fates during early development and how their signaling mechanisms are coordinated to concomitantly pattern AP and DV tissues.
Collapse
Affiliation(s)
- Francesca B Tuazon
- Department of Cell and Developmental Biology, University of Pennsylvania, Perelman School of Medicine, 1152 BRBII/III, 421 Curie Boulevard, Philadelphia, PA 19104-6058, United States
| | - Mary C Mullins
- Department of Cell and Developmental Biology, University of Pennsylvania, Perelman School of Medicine, 1152 BRBII/III, 421 Curie Boulevard, Philadelphia, PA 19104-6058, United States.
| |
Collapse
|
43
|
Jayakody SA, Gonzalez-Cordero A, Ali RR, Pearson RA. Cellular strategies for retinal repair by photoreceptor replacement. Prog Retin Eye Res 2015; 46:31-66. [PMID: 25660226 DOI: 10.1016/j.preteyeres.2015.01.003] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 01/13/2015] [Accepted: 01/19/2015] [Indexed: 02/08/2023]
Abstract
Loss of photoreceptors due to retinal degeneration is a major cause of blindness in the developed world. While no effective treatment is currently available, cell replacement therapy, using pluripotent stem cell-derived photoreceptor precursor cells, may be a feasible future treatment. Recent reports have demonstrated rescue of visual function following the transplantation of immature photoreceptors and we have seen major advances in our ability to generate transplantation-competent donor cells from stem cell sources. Moreover, we are beginning to realise the possibilities of using endogenous populations of cells from within the retina itself to mediate retinal repair. Here, we present a review of our current understanding of endogenous repair mechanisms together with recent progress in the use of both ocular and pluripotent stem cells for the treatment of photoreceptor loss. We consider how our understanding of retinal development has underpinned many of the recent major advances in translation and moved us closer to the goal of restoring vision by cellular means.
Collapse
Affiliation(s)
- Sujatha A Jayakody
- Gene and Cell Therapy Group, Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath St, London EC1V 9EL, UK
| | - Anai Gonzalez-Cordero
- Gene and Cell Therapy Group, Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath St, London EC1V 9EL, UK
| | - Robin R Ali
- Gene and Cell Therapy Group, Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath St, London EC1V 9EL, UK; NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, City Road, London EC1V 2PD, UK
| | - Rachael A Pearson
- Gene and Cell Therapy Group, Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath St, London EC1V 9EL, UK.
| |
Collapse
|
44
|
Zebrafish Rnf111 is encoded by multiple transcripts and is required for epiboly progression and prechordal plate development. Differentiation 2015; 89:22-30. [PMID: 25619648 DOI: 10.1016/j.diff.2014.12.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 12/04/2014] [Accepted: 12/22/2014] [Indexed: 12/12/2022]
Abstract
Arkadia (also known as RING finger 111) encodes a nuclear E3 ubiquitin ligase that targets intracellular effectors and modulators of TGFβ/Nodal-related signaling for polyubiquitination and proteasome-dependent degradation. In the mouse, loss of Arkadia results in early embryonic lethality, with defects attributed to compromised Nodal signaling. Here, we report the isolation of zebrafish arkadia/rnf111, which is represented by 5 transcript variants. arkadia/rnf111 is broadly expressed during the blastula and gastrula stages, with eventual enrichment in the anterior mesendoderm, including the prechordal plate. Morpholino knockdown experiments reveal an unexpected role for Arkadia/Rnf111 in both early blastula organization and epiboly progression. Using a splice junction morpholino, we present additional evidence that arkadia/rnf111 transcript variants containing a 3' alternative exon are specifically required for epiboly progression in the late gastrula. This result suggests that arkadia/rnf111 transcript variants encode functionally relevant protein isoforms that provide additional intracellular flexibility and regulation to the Nodal signaling pathway.
Collapse
|
45
|
Kang N, Won M, Rhee M, Ro H. Siah ubiquitin ligases modulate nodal signaling during zebrafish embryonic development. Mol Cells 2014; 37:389-98. [PMID: 24823357 PMCID: PMC4044310 DOI: 10.14348/molcells.2014.0032] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 03/27/2014] [Accepted: 03/31/2014] [Indexed: 01/15/2023] Open
Abstract
Siah2 is a zebrafish homologue of mammalian Siah family. Siah acts as an E3 ubiquitin ligase that binds proteins destined for degradation. Extensive homology between siah and Drosophila Siah homologue (sina) suggests their important physiological roles during embryonic development. However, detailed functional studies of Siah in vertebrate development have not been carried out. Here we report that Siah2 specifically augments nodal related gene expression in marginal blastomeres at late blastula through early gastrula stages of zebrafish embryos. Siah2 dependent Nodal signaling augmentation is confirmed by cell-based reporter gene assays using 293T cells and 3TPluciferase reporter plasmid. We also established a molecular hierarchy of Siah as a upstream regulator of FoxH1/Fast1 transcriptional factor in Nodal signaling. Elevated expression of nodal related genes by overexpression of Siah2 was enough to override the inhibitory effects of atv and lft2 on the Nodal signaling. In particular, E3 ubiquitin ligase activity of Siah2 is critical to limit the duration and/or magnitude of Nodal signaling. Additionally, since the embryos injected with Siah morpholinos mimicked the atv overexpression phenotype at least in part, our data support a model in which Siah is involved in mesendoderm patterning via modulating Nodal signaling.
Collapse
Affiliation(s)
- Nami Kang
- Department of Biological Sciences, College of Bioscience and Biotechnology, Chungnam National University, Daejeon 305-764,
Korea
| | - Minho Won
- Program in Genomics of Differentiation, Eunice Kennedy Shiver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland,
USA
| | - Myungchull Rhee
- Department of Biological Sciences, College of Bioscience and Biotechnology, Chungnam National University, Daejeon 305-764,
Korea
| | - Hyunju Ro
- Department of Biological Sciences, College of Bioscience and Biotechnology, Chungnam National University, Daejeon 305-764,
Korea
| |
Collapse
|
46
|
Neugebauer JM, Yost HJ. FGF signaling is required for brain left-right asymmetry and brain midline formation. Dev Biol 2014; 386:123-34. [PMID: 24333178 PMCID: PMC3970204 DOI: 10.1016/j.ydbio.2013.11.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 11/15/2013] [Accepted: 11/18/2013] [Indexed: 02/03/2023]
Abstract
Early disruption of FGF signaling alters left-right (LR) asymmetry throughout the embryo. Here we uncover a role for FGF signaling that specifically disrupts brain asymmetry, independent of normal lateral plate mesoderm (LPM) asymmetry. When FGF signaling is inhibited during mid-somitogenesis, asymmetrically expressed LPM markers southpaw and lefty2 are not affected. However, asymmetrically expressed brain markers lefty1 and cyclops become bilateral. We show that FGF signaling controls expression of six3b and six7, two transcription factors required for repression of asymmetric lefty1 in the brain. We found that Z0-1, atypical PKC (aPKC) and β-catenin protein distribution revealed a midline structure in the forebrain that is dependent on a balance of FGF signaling. Ectopic activation of FGF signaling leads to overexpression of six3b, loss of organized midline adherins junctions and bilateral loss of lefty1 expression. Reducing FGF signaling leads to a reduction in six3b and six7 expression, an increase in cell boundary formation in the brain midline, and bilateral expression of lefty1. Together, these results suggest a novel role for FGF signaling in the brain to control LR asymmetry, six transcription factor expressions, and a midline barrier structure.
Collapse
Affiliation(s)
- Judith M Neugebauer
- Department of Neurobiology & Anatomy, University of Utah School of Medicine, Eccles Institute of Human Genetics, Building 533, Room 3160, 15 North 2030 East, Salt Lake City, UT 84112-5330, United States
| | - H Joseph Yost
- Department of Neurobiology & Anatomy, University of Utah School of Medicine, Eccles Institute of Human Genetics, Building 533, Room 3160, 15 North 2030 East, Salt Lake City, UT 84112-5330, United States.
| |
Collapse
|
47
|
Lin CY, Lee HC, Chen HC, Hsieh CC, Tsai HJ. Normal function of Myf5 during gastrulation is required for pharyngeal arch cartilage development in zebrafish embryos. Zebrafish 2013; 10:486-99. [PMID: 23992145 DOI: 10.1089/zeb.2013.0903] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Myf5, a myogenic regulatory factor, plays a key role in regulating muscle differentiation. However, it is not known if Myf5 has a regulatory role during early embryogenesis. Here, we used myf5-morpholino oligonucleotides [MO] to knock down myf5 expression and demonstrated a series of results pointing to the functional roles of Myf5 during early embryogenesis: (1) reduced head size resulting from abnormal morphology in the cranial skeleton; (2) decreased expressions of the cranial neural crest (CNC) markers foxd3, sox9a, dlx2, and col2a1; (3) defect in the chondrogenic neural crest similar to that of fgf3 morphants; (4) reduced fgf3/fgf8 transcripts in the cephalic mesoderm rescued by co-injection of myf5 wobble-mismatched mRNA together with myf5-MO1 during 12 h postfertilization; (5) abnormal patterns of axial and non-axial mesoderm causing expansion of the dorsal organizer, and (6) increased bmp4 gradient, but reduced fgf3/fgf8 marginal gradient, during gastrulation. Interestingly, overexpression of fgf3 could rescue the cranial cartilage defects caused by myf5-MO1, suggesting that Myf5 modulates craniofacial cartilage development through the fgf3 signaling pathway. Together, the loss of Myf5 function results in a cascade effect that begins with abnormal formation of the dorsal organizer during gastrulation, causing, in turn, defects in the CNC and cranial cartilage of myf5-knockdown embryos.
Collapse
Affiliation(s)
- Cheng-Yung Lin
- Institute of Molecular and Cellular Biology, National Taiwan University , Taipei, Taiwan
| | | | | | | | | |
Collapse
|
48
|
Lim S, Wang Y, Yu X, Huang Y, Featherstone MS, Sampath K. A simple strategy for heritable chromosomal deletions in zebrafish via the combinatorial action of targeting nucleases. Genome Biol 2013; 14:R69. [PMID: 23815890 PMCID: PMC4054832 DOI: 10.1186/gb-2013-14-7-r69] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 07/01/2013] [Indexed: 12/21/2022] Open
Abstract
Precise and effective genome-editing tools are essential for functional genomics and gene therapy. Targeting nucleases have been successfully used to edit genomes. However, whole-locus or element-specific deletions abolishing transcript expression have not previously been reported. Here, we show heritable targeting of locus-specific deletions in the zebrafish nodal-related genes squint (sqt) and cyclops (cyc). Our strategy of heritable chromosomal editing can be used for disease modeling, analyzing gene clusters, regulatory regions, and determining the functions of non-coding RNAs in genomes.
Collapse
|
49
|
Sinn R, Wittbrodt J. An eye on eye development. Mech Dev 2013; 130:347-58. [PMID: 23684892 DOI: 10.1016/j.mod.2013.05.001] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 05/04/2013] [Accepted: 05/07/2013] [Indexed: 12/29/2022]
Abstract
The vertebrate eye is composed of both surface ectodermal and neuroectodermal derivatives that evaginate laterally from an epithelial anlage of the forming diencephalon. The retina is composed of a limited number of neuronal and non-neuronal cell types and is seen as a model for the brain with reduced complexity. The eye develops in a stereotypic manner building on evolutionarily conserved molecular networks. Eye formation is initiated at the onset of gastrulation by the determination of the eye field in the anterior neuroectoderm. Homeobox transcription factors, in particular Six3 are crucially involved in the establishment and maintenance of retinal identity. The eye field expands by proliferation as gastrulation proceeds and is initially confined to a single retinal primordium by the differential activity of specifying transcription factors. This central field is subsequently split in response to secreted factors emanating from the ventral midline. Concomitant with medio-lateral patterning at the onset of neurulation, morphogenesis sets in and laterally evaginates the optic vesicle. Strikingly during this process the neuroectoderm in the eye field transiently loses epithelial features and cells migrate individually. In a second morphogenetic event, the vesicle is transformed into the optic cup, concomitant with onset and progression of retinal differentiation. Accompanying optic cup morphogenesis, neural differentiation is initiated from a retinal signalling centre in a stereotypic and species specific manner by secreted signalling factors. Here we will give an overview of key events during vertebrate eye formation and highlight key players in the respective processes.
Collapse
Affiliation(s)
- Rebecca Sinn
- Centre for Organismal Studies, COS Heidelberg, University of Heidelberg, Im Neuenheimer Feld 230, 69120 Heidelberg, Germany
| | | |
Collapse
|
50
|
Hashiguchi M, Mullins MC. Anteroposterior and dorsoventral patterning are coordinated by an identical patterning clock. Development 2013; 140:1970-80. [PMID: 23536566 DOI: 10.1242/dev.088104] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Establishment of the body plan in vertebrates depends on the temporally coordinated patterning of tissues along the body axes. We have previously shown that dorsoventral (DV) tissues are temporally patterned progressively from anterior to posterior by a BMP signaling pathway. Here we report that DV patterning along the zebrafish anteroposterior (AP) axis is temporally coordinated with AP patterning by an identical patterning clock. We altered AP patterning by inhibiting or activating FGF, Wnt or retinoic acid signaling combined with inhibition of BMP signaling at a series of developmental time points, which revealed that the temporal progression of DV patterning is directly coordinated with AP patterning. We investigated how these signaling pathways are integrated and suggest a model for how DV and AP patterning are temporally coordinated. It has been shown that in Xenopus dorsal tissues FGF and Wnt signaling quell BMP signaling by degrading phosphorylated (P) Smad1/5, the BMP pathway signal transducer, via phosphorylation of the Smad1/5 linker region. We show that in zebrafish FGF/MAPK, but not Wnt/GSK3, phosphorylation of the Smad1/5 linker region localizes to a ventral vegetal gastrula region that could coordinate DV patterning with AP patterning ventrally without degrading P-Smad1/5. Furthermore, we demonstrate that alteration of the MAPK phosphorylation sites in the Smad5 linker causes precocious patterning of DV tissues along the AP axis during gastrulation. Thus, DV and AP patterning are intimately coordinated to allow cells to acquire both positional and temporal information simultaneously.
Collapse
Affiliation(s)
- Megumi Hashiguchi
- Department of Cell and Developmental Biology, University of Pennsylvania, Perelman School of Medicine, 421 Curie Blvd., Philadelphia, PA 19104-6058, USA
| | | |
Collapse
|