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Kocere A, Lalonde RL, Mosimann C, Burger A. Lateral thinking in syndromic congenital cardiovascular disease. Dis Model Mech 2023; 16:dmm049735. [PMID: 37125615 PMCID: PMC10184679 DOI: 10.1242/dmm.049735] [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] [Indexed: 05/02/2023] Open
Abstract
Syndromic birth defects are rare diseases that can present with seemingly pleiotropic comorbidities. Prime examples are rare congenital heart and cardiovascular anomalies that can be accompanied by forelimb defects, kidney disorders and more. Whether such multi-organ defects share a developmental link remains a key question with relevance to the diagnosis, therapeutic intervention and long-term care of affected patients. The heart, endothelial and blood lineages develop together from the lateral plate mesoderm (LPM), which also harbors the progenitor cells for limb connective tissue, kidneys, mesothelia and smooth muscle. This developmental plasticity of the LPM, which founds on multi-lineage progenitor cells and shared transcription factor expression across different descendant lineages, has the potential to explain the seemingly disparate syndromic defects in rare congenital diseases. Combining patient genome-sequencing data with model organism studies has already provided a wealth of insights into complex LPM-associated birth defects, such as heart-hand syndromes. Here, we summarize developmental and known disease-causing mechanisms in early LPM patterning, address how defects in these processes drive multi-organ comorbidities, and outline how several cardiovascular and hematopoietic birth defects with complex comorbidities may be LPM-associated diseases. We also discuss strategies to integrate patient sequencing, data-aggregating resources and model organism studies to mechanistically decode congenital defects, including potentially LPM-associated orphan diseases. Eventually, linking complex congenital phenotypes to a common LPM origin provides a framework to discover developmental mechanisms and to anticipate comorbidities in congenital diseases affecting the cardiovascular system and beyond.
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Affiliation(s)
- Agnese Kocere
- University of Colorado School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, Aurora, CO 80045, USA
- Department of Molecular Life Science, University of Zurich, 8057 Zurich, Switzerland
| | - Robert L. Lalonde
- University of Colorado School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, Aurora, CO 80045, USA
| | - Christian Mosimann
- University of Colorado School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, Aurora, CO 80045, USA
| | - Alexa Burger
- University of Colorado School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, Aurora, CO 80045, USA
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2
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Persistent Ventricle Partitioning in the Adult Zebrafish Heart. J Cardiovasc Dev Dis 2021; 8:jcdd8040041. [PMID: 33918756 PMCID: PMC8070482 DOI: 10.3390/jcdd8040041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/02/2021] [Accepted: 04/07/2021] [Indexed: 02/07/2023] Open
Abstract
The vertebrate heart integrates cells from the early-differentiating first heart field (FHF) and the later-differentiating second heart field (SHF), both emerging from the lateral plate mesoderm. In mammals, this process forms the basis for the development of the left and right ventricle chambers and subsequent chamber septation. The single ventricle-forming zebrafish heart also integrates FHF and SHF lineages during embryogenesis, yet the contributions of these two myocardial lineages to the adult zebrafish heart remain incompletely understood. Here, we characterize the myocardial labeling of FHF descendants in both the developing and adult zebrafish ventricle. Expanding previous findings, late gastrulation-stage labeling using drl-driven CreERT2 recombinase with a myocardium-specific, myl7-controlled, loxP reporter results in the predominant labeling of FHF-derived outer curvature and the right side of the embryonic ventricle. Raised to adulthood, such lineage-labeled hearts retain broad areas of FHF cardiomyocytes in a region of the ventricle that is positioned at the opposite side to the atrium and encompasses the apex. Our data add to the increasing evidence for a persisting cell-based compartmentalization of the adult zebrafish ventricle even in the absence of any physical boundary.
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3
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Yuan X, Scott IC, Wilson MD. Heart Enhancers: Development and Disease Control at a Distance. Front Genet 2021; 12:642975. [PMID: 33777110 PMCID: PMC7987942 DOI: 10.3389/fgene.2021.642975] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 01/29/2021] [Indexed: 12/14/2022] Open
Abstract
Bound by lineage-determining transcription factors and signaling effectors, enhancers play essential roles in controlling spatiotemporal gene expression profiles during development, homeostasis and disease. Recent synergistic advances in functional genomic technologies, combined with the developmental biology toolbox, have resulted in unprecedented genome-wide annotation of heart enhancers and their target genes. Starting with early studies of vertebrate heart enhancers and ending with state-of-the-art genome-wide enhancer discovery and testing, we will review how studying heart enhancers in metazoan species has helped inform our understanding of cardiac development and disease.
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Affiliation(s)
- Xuefei Yuan
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Ian C. Scott
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Michael D. Wilson
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
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4
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Kemmler CL, Riemslagh FW, Moran HR, Mosimann C. From Stripes to a Beating Heart: Early Cardiac Development in Zebrafish. J Cardiovasc Dev Dis 2021; 8:17. [PMID: 33578943 PMCID: PMC7916704 DOI: 10.3390/jcdd8020017] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/05/2021] [Accepted: 02/07/2021] [Indexed: 12/18/2022] Open
Abstract
The heart is the first functional organ to form during vertebrate development. Congenital heart defects are the most common type of human birth defect, many originating as anomalies in early heart development. The zebrafish model provides an accessible vertebrate system to study early heart morphogenesis and to gain new insights into the mechanisms of congenital disease. Although composed of only two chambers compared with the four-chambered mammalian heart, the zebrafish heart integrates the core processes and cellular lineages central to cardiac development across vertebrates. The rapid, translucent development of zebrafish is amenable to in vivo imaging and genetic lineage tracing techniques, providing versatile tools to study heart field migration and myocardial progenitor addition and differentiation. Combining transgenic reporters with rapid genome engineering via CRISPR-Cas9 allows for functional testing of candidate genes associated with congenital heart defects and the discovery of molecular causes leading to observed phenotypes. Here, we summarize key insights gained through zebrafish studies into the early patterning of uncommitted lateral plate mesoderm into cardiac progenitors and their regulation. We review the central genetic mechanisms, available tools, and approaches for modeling congenital heart anomalies in the zebrafish as a representative vertebrate model.
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Affiliation(s)
| | | | | | - Christian Mosimann
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine and Children’s Hospital Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA; (C.L.K.); (F.W.R.); (H.R.M.)
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5
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Transcription Factors of the bHLH Family Delineate Vertebrate Landmarks in the Nervous System of a Simple Chordate. Genes (Basel) 2020; 11:genes11111262. [PMID: 33114624 PMCID: PMC7693978 DOI: 10.3390/genes11111262] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Accepted: 10/12/2020] [Indexed: 02/07/2023] Open
Abstract
Tunicates are marine invertebrates whose tadpole-like larvae feature a highly simplified version of the chordate body plan. Similar to their distant vertebrate relatives, tunicate larvae develop a regionalized central nervous system and form distinct neural structures, which include a rostral sensory vesicle, a motor ganglion, and a caudal nerve cord. The sensory vesicle contains a photoreceptive complex and a statocyst, and based on the comparable expression patterns of evolutionarily conserved marker genes, it is believed to include proto-hypothalamic and proto-retinal territories. The evolutionarily conserved molecular fingerprints of these landmarks of the vertebrate brain consist of genes encoding for different transcription factors, and of the gene batteries that they control, and include several members of the bHLH family. Here we review the complement of bHLH genes present in the streamlined genome of the tunicate Ciona robusta and their current classification, and summarize recent studies on proneural bHLH transcription factors and their expression territories. We discuss the possible roles of bHLH genes in establishing the molecular compartmentalization of the enticing nervous system of this unassuming chordate.
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Kim K, Gibboney S, Razy-Krajka F, Lowe EK, Wang W, Stolfi A. Regulation of Neurogenesis by FGF Signaling and Neurogenin in the Invertebrate Chordate Ciona. Front Cell Dev Biol 2020; 8:477. [PMID: 32656209 PMCID: PMC7324659 DOI: 10.3389/fcell.2020.00477] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 05/21/2020] [Indexed: 12/22/2022] Open
Abstract
Neurogenesis is a complex sequence of cellular processes and behaviors driven by the coordinated expression of conserved effectors. The bipolar tail neurons (BTNs) of Ciona develop according to a highly dynamic, yet highly stereotyped developmental program and thus could serve as an accessible model system for neurogenesis, including underlying cell behaviors like neuronal delamination, migration, and polarized axon outgrowth. Here we investigate both the upstream events that shape BTN neurogenesis through spatiotemporal regulation of the conserved proneural factor Neurog, spatiotemporal, and the gene expression profile of differentiating BTNs downstream of Neurog activity. We show that, although early FGF signaling is required for Neurog expression and BTN specification, Fgf8/17/18 is expressed in tail tip cells at later stages and suppresses sustained Neurog expression in the anterior BTN (aBTN) lineage, such that only one cell (the one furthest from the source of Fgf8/17/18) maintains Neurog expression and becomes a neuron. Curiously, Fgf8/17/18 might not affect neurogenesis of the posterior BTNs (pBTNs), which are in direct contact with the Fgf8/17/18-expressing cells. Finally, to profile gene expression associated with BTN neurogenesis we performed RNAseq of isolated BTN lineage cells in which BTN neurogenesis was enhanced or suppressed by perturbing Neurog function. This allowed us to identify several candidate genes that might play conserved roles in neurogenesis and neuronal migration in other animals, including mammals.
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Affiliation(s)
- Kwantae Kim
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
| | - Susanne Gibboney
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
| | - Florian Razy-Krajka
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
| | - Elijah K. Lowe
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
| | - Wei Wang
- Department of Biology, New York University, New York, NY, United States
| | - Alberto Stolfi
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
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7
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Razy-Krajka F, Stolfi A. Regulation and evolution of muscle development in tunicates. EvoDevo 2019; 10:13. [PMID: 31249657 PMCID: PMC6589888 DOI: 10.1186/s13227-019-0125-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 06/08/2019] [Indexed: 12/16/2022] Open
Abstract
For more than a century, studies on tunicate muscle formation have revealed many principles of cell fate specification, gene regulation, morphogenesis, and evolution. Here, we review the key studies that have probed the development of all the various muscle cell types in a wide variety of tunicate species. We seize this occasion to explore the implications and questions raised by these findings in the broader context of muscle evolution in chordates.
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Affiliation(s)
- Florian Razy-Krajka
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, USA
| | - Alberto Stolfi
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, USA
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8
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Poelmann RE, Gittenberger-de Groot AC. Development and evolution of the metazoan heart. Dev Dyn 2019; 248:634-656. [PMID: 31063648 PMCID: PMC6767493 DOI: 10.1002/dvdy.45] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 04/25/2019] [Accepted: 04/29/2019] [Indexed: 12/19/2022] Open
Abstract
The mechanisms of the evolution and development of the heart in metazoans are highlighted, starting with the evolutionary origin of the contractile cell, supposedly the precursor of cardiomyocytes. The last eukaryotic common ancestor is likely a combination of several cellular organisms containing their specific metabolic pathways and genetic signaling networks. During evolution, these tool kits diversified. Shared parts of these conserved tool kits act in the development and functioning of pumping hearts and open or closed circulations in such diverse species as arthropods, mollusks, and chordates. The genetic tool kits became more complex by gene duplications, addition of epigenetic modifications, influence of environmental factors, incorporation of viral genomes, cardiac changes necessitated by air‐breathing, and many others. We evaluate mechanisms involved in mollusks in the formation of three separate hearts and in arthropods in the formation of a tubular heart. A tubular heart is also present in embryonic stages of chordates, providing the septated four‐chambered heart, in birds and mammals passing through stages with first and second heart fields. The four‐chambered heart permits the formation of high‐pressure systemic and low‐pressure pulmonary circulation in birds and mammals, allowing for high metabolic rates and maintenance of body temperature. Crocodiles also have a (nearly) separated circulation, but their resting temperature conforms with the environment. We argue that endothermic ancestors lost the capacity to elevate their body temperature during evolution, resulting in ectothermic modern crocodilians. Finally, a clinically relevant paragraph reviews the occurrence of congenital cardiac malformations in humans as derailments of signaling pathways during embryonic development. The cardiac regulatory toolkit contains many factors including epigenetic, genetic, viral, hemodynamic, and environmental factors, but also transcriptional activators, repressors, duplicated genes, redundancies and dose‐dependancies. Numerous toolkits regulate mechanisms including cell‐cell interactions, EMT, mitosis patterns, cell migration and differentiation and left/right sidedness involved in the development of endocardial cushions, looping, septum complexes, pharyngeal arch arteries, chamber and valve formation and conduction system. Evolutionary development of the yolk sac circulation likely preceded the advent of endothermy in amniotes. Parallel evolutionary traits regulate the development of contractile pumps in various taxa often in conjunction with the gut, lungs and excretory organs.
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Affiliation(s)
- Robert E Poelmann
- Institute of Biology, Department of Animal Sciences and Health, Leiden University, Leiden, The Netherlands.,Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands
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9
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Prünster MM, Ricci L, Brown FD, Tiozzo S. Modular co-option of cardiopharyngeal genes during non-embryonic myogenesis. EvoDevo 2019; 10:3. [PMID: 30867897 PMCID: PMC6399929 DOI: 10.1186/s13227-019-0116-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 02/15/2019] [Indexed: 01/03/2023] Open
Abstract
Background In chordates, cardiac and body muscles arise from different embryonic origins. In addition, myogenesis can be triggered in adult organisms, during asexual development or regeneration. In non-vertebrate chordates like ascidians, muscles originate from embryonic precursors regulated by a conserved set of genes that orchestrate cell behavior and dynamics during development. In colonial ascidians, besides embryogenesis and metamorphosis, an adult can propagate asexually via blastogenesis, skipping embryo and larval stages, and form anew the adult body, including the complete body musculature. Results To investigate the cellular origin and mechanisms that trigger non-embryonic myogenesis, we followed the expression of ascidian myogenic genes during Botryllus schlosseri blastogenesis and reconstructed the dynamics of muscle precursors. Based on the expression dynamics of Tbx1/10, Ebf, Mrf, Myh3 for body wall and of FoxF, Tbx1/10, Nk4, Myh2 for heart development, we show that the embryonic factors regulating myogenesis are only partially co-opted in blastogenesis, and that markers for muscle precursors are expressed in two separate domains: the dorsal tube and the ventral mesenchyma. Conclusions Regardless of the developmental pathway, non-embryonic myogenesis shares a similar molecular and anatomical setup as embryonic myogenesis, but implements a co-option and loss of molecular modules. We then propose that the cellular precursors contributing to heart and body muscles may have different origins and may be coordinated by different developmental pathways. Electronic supplementary material The online version of this article (10.1186/s13227-019-0116-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Maria Mandela Prünster
- 1Laboratoire de Biologie du Développement de Villefranche-sur-mer (LBDV), CNRS, Sorbonne Université, 06230 Villefranche sur Mer, France
| | - Lorenzo Ricci
- 1Laboratoire de Biologie du Développement de Villefranche-sur-mer (LBDV), CNRS, Sorbonne Université, 06230 Villefranche sur Mer, France.,2Department of Organismic and Evolutionary Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138 USA
| | - Federico D Brown
- 3Departamento de Zoologia, Instituto Biociências, Universidade de São Paulo, São Paulo, SP CEP 05508-090 Brazil.,4Centro de Biologia Marinha (CEBIMar), Universidade de São Paulo, São Sebastião, SP CEP 11612-109 Brazil
| | - Stefano Tiozzo
- 1Laboratoire de Biologie du Développement de Villefranche-sur-mer (LBDV), CNRS, Sorbonne Université, 06230 Villefranche sur Mer, France
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10
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Scimone ML, Wurtzel O, Malecek K, Fincher CT, Oderberg IM, Kravarik KM, Reddien PW. foxF-1 Controls Specification of Non-body Wall Muscle and Phagocytic Cells in Planarians. Curr Biol 2018; 28:3787-3801.e6. [PMID: 30471994 DOI: 10.1016/j.cub.2018.10.030] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 08/17/2018] [Accepted: 10/10/2018] [Indexed: 12/31/2022]
Abstract
Planarians are flatworms capable of regenerating any missing body part in a process requiring stem cells and positional information. Muscle is a major source of planarian positional information and consists of several types of fibers with distinct regulatory roles in regeneration. The transcriptional regulatory programs used to specify different muscle fibers are poorly characterized. Using single-cell RNA sequencing, we define the transcriptomes of planarian dorsal-ventral muscle (DVM), intestinal muscle (IM), and pharynx muscle. This analysis identifies foxF-1, which encodes a broadly conserved Fox-family transcription factor, as a master transcriptional regulator of all non-body wall muscle. The transcription factors encoded by nk4 and gata4/5/6-2 specify two different subsets of DVM, lateral and medial, respectively, whereas gata4/5/6-3 specifies IM. These muscle types all express planarian patterning genes. Both lateral and medial DVM are required for medial-lateral patterning in regeneration, whereas medial DVM and IM have a role in maintaining and regenerating intestine morphology. In addition to the role in muscle, foxF-1 is required for the specification of multiple cell types with transcriptome similarities, including high expression levels of cathepsin genes. These cells include pigment cells, glia, and several other cells with unknown function. cathepsin+ cells phagocytose E. coli, suggesting these are phagocytic cells. In conclusion, we describe a regulatory program for planarian muscle cell subsets and phagocytic cells, both driven by foxF-1. FoxF proteins specify different mesoderm-derived tissues in other organisms, suggesting that FoxF regulates formation of an ancient and broadly conserved subset of mesoderm derivatives in the Bilateria.
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Affiliation(s)
- M Lucila Scimone
- Howard Hughes Medical Institute, Whitehead Institute, and Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - Omri Wurtzel
- Howard Hughes Medical Institute, Whitehead Institute, and Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - Kathryn Malecek
- Howard Hughes Medical Institute, Whitehead Institute, and Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - Christopher T Fincher
- Howard Hughes Medical Institute, Whitehead Institute, and Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - Isaac M Oderberg
- Howard Hughes Medical Institute, Whitehead Institute, and Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - Kellie M Kravarik
- Howard Hughes Medical Institute, Whitehead Institute, and Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - Peter W Reddien
- Howard Hughes Medical Institute, Whitehead Institute, and Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA.
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11
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Sasakura Y, Hozumi A. Formation of adult organs through metamorphosis in ascidians. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2017; 7. [PMID: 29105358 DOI: 10.1002/wdev.304] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 08/28/2017] [Accepted: 09/11/2017] [Indexed: 02/05/2023]
Abstract
The representative characteristic of ascidians is their vertebrate-like, tadpole shape at the larval stage. Ascidians lose the tadpole shape through metamorphosis to become adults with a nonmotile, sessile body and a shape generally considered distinct from that of vertebrates. Solitary ascidians including Ciona species are extensively studied to understand the developmental mechanisms of ascidians, and to compare these mechanisms with their counterparts in vertebrates. In these ascidian species, the digestive and circulatory systems are not well developed in the larval trunk and the larvae do not take food. This is in contrast with the inner conditions of vertebrate tadpoles, which have functional organs comparable to those of adults. The adult organs and tissues of these ascidians become functional during metamorphosis that is completed quickly, suggesting that the ascidian larvae of solitary species are a transient stage of development. We here discuss how the cells and tissues in the ascidian larval body are converted into those of adults. The hearts of ascidians and vertebrates use closely related cellular and molecular mechanisms that suggest their shared origin. Hox genes of ascidians are essential for forming adult endodermal structures. To fully understand the development and evolution of chordates, a complete elucidation of the mechanisms underlying the adult tissue/organ formation of ascidians will be needed. WIREs Dev Biol 2018, 7:e304. doi: 10.1002/wdev.304 This article is categorized under: Comparative Development and Evolution > Body Plan Evolution Early Embryonic Development > Development to the Basic Body Plan.
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Affiliation(s)
- Yasunori Sasakura
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
| | - Akiko Hozumi
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
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12
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Abstract
Cardiac cell specification and the genetic determinants that govern this process are highly conserved among Chordates. Recent studies have established the importance of evolutionarily-conserved mechanisms in the study of congenital heart defects and disease, as well as cardiac regeneration. As a basal Chordate, the Ciona model system presents a simple scaffold that recapitulates the basic blueprint of cardiac development in Chordates. Here we will focus on the development and cellular structure of the heart of the ascidian Ciona as compared to other Chordates, principally vertebrates. Comparison of the Ciona model system to heart development in other Chordates presents great potential for dissecting the genetic mechanisms that underlie congenital heart defects and disease at the cellular level and might provide additional insight into potential pathways for therapeutic cardiac regeneration.
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13
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Dubois L, Frendo JL, Chanut-Delalande H, Crozatier M, Vincent A. Genetic dissection of the Transcription Factor code controlling serial specification of muscle identities in Drosophila. eLife 2016; 5. [PMID: 27438571 PMCID: PMC4954755 DOI: 10.7554/elife.14979] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 07/11/2016] [Indexed: 12/30/2022] Open
Abstract
Each Drosophila muscle is seeded by one Founder Cell issued from terminal division of a Progenitor Cell (PC). Muscle identity reflects the expression by each PC of a specific combination of identity Transcription Factors (iTFs). Sequential emergence of several PCs at the same position raised the question of how developmental time controlled muscle identity. Here, we identified roles of Anterior Open and ETS domain lacking in controlling PC birth time and Eyes absent, No Ocelli, and Sine oculis in specifying PC identity. The windows of transcription of these and other TFs in wild type and mutant embryos, revealed a cascade of regulation integrating time and space, feed-forward loops and use of alternative transcription start sites. These data provide a dynamic view of the transcriptional control of muscle identity in Drosophila and an extended framework for studying interactions between general myogenic factors and iTFs in evolutionary diversification of muscle shapes. DOI:http://dx.doi.org/10.7554/eLife.14979.001 Animals have many different muscles of various shapes and sizes that are suited to specific tasks and behaviors. The fruit fly known as Drosophila has a fairly simple musculature, which makes it an ideal model animal to investigate how different muscles form. In fruit fly embryos, cells called progenitor cells divide to produce the cells that will go on to form the different muscles. Proteins called identity Transcription Factors are present in progenitor cells. Different combinations of identity Transcription Factors can switch certain genes on or off to control the muscle shapes in specific areas of an embryo. However, progenitor cells born in the same area but at different times display different patterns of identity Transcription Factors; this suggests that timing also influences the orientation, shape and size of a developing muscle, also known as muscle identity. Dubois et al. used a genetic screen to look for identity Transcription Factors and the roles these proteins play in muscle formation in fruit flies. Tracking the activity of these proteins revealed a precise timeline for specifying muscle identity. This timeline involves cascades of different identity Transcription Factors accumulating in the cells, which act to make sure that distinct muscle shapes are made. In flies with specific mutations, the timing of these events is disrupted, which results in muscles forming with different shapes to those seen in normal flies. The findings of Dubois et al. suggest that the timing of when particular progenitor cells form, as well as their location in the embryo, contribute to determine the shapes of muscles. The next step following on from this work is to use video-microscopy to track identity Transcription Factors when the final muscle shapes emerge. Further experiments will investigate how identity Transcription Factors work together with proteins that are directly involved in muscle development. DOI:http://dx.doi.org/10.7554/eLife.14979.002
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Affiliation(s)
- Laurence Dubois
- Centre de Biologie du Développement (CBD), CNRS and Université de Toulouse, Toulouse, France.,Centre de Biologie Intégrative (CBI), CNRS and Université de Toulouse, Toulouse, France
| | - Jean-Louis Frendo
- Centre de Biologie du Développement (CBD), CNRS and Université de Toulouse, Toulouse, France.,Centre de Biologie Intégrative (CBI), CNRS and Université de Toulouse, Toulouse, France
| | - Hélène Chanut-Delalande
- Centre de Biologie du Développement (CBD), CNRS and Université de Toulouse, Toulouse, France.,Centre de Biologie Intégrative (CBI), CNRS and Université de Toulouse, Toulouse, France
| | - Michèle Crozatier
- Centre de Biologie du Développement (CBD), CNRS and Université de Toulouse, Toulouse, France.,Centre de Biologie Intégrative (CBI), CNRS and Université de Toulouse, Toulouse, France
| | - Alain Vincent
- Centre de Biologie du Développement (CBD), CNRS and Université de Toulouse, Toulouse, France.,Centre de Biologie Intégrative (CBI), CNRS and Université de Toulouse, Toulouse, France
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14
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Trivedi S, Aloufi AA, Ansari AA, Ghosh SK. Role of DNA barcoding in marine biodiversity assessment and conservation: An update. Saudi J Biol Sci 2016; 23:161-71. [PMID: 26980996 PMCID: PMC4778524 DOI: 10.1016/j.sjbs.2015.01.001] [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: 09/18/2014] [Revised: 12/09/2014] [Accepted: 01/05/2015] [Indexed: 12/18/2022] Open
Abstract
More than two third area of our planet is covered by oceans and assessment of marine biodiversity is a challenging task. With the increasing global population, there is a tendency to exploit marine resources for food, energy and other requirements. This puts pressure on the fragile marine environment and necessitates sustainable conservation efforts. Marine species identification using traditional taxonomical methods is often burdened with taxonomic controversies. Here we discuss the comparatively new concept of DNA barcoding and its significance in marine perspective. This molecular technique can be useful in the assessment of cryptic species which is widespread in marine environment and linking the different life cycle stages to the adult which is difficult to accomplish in the marine ecosystem. Other advantages of DNA barcoding include authentication and safety assessment of seafood, wildlife forensics, conservation genetics and detection of invasive alien species (IAS). Global DNA barcoding efforts in the marine habitat include MarBOL, CeDAMar, CMarZ, SHARK-BOL, etc. An overview on DNA barcoding of different marine groups ranging from the microbes to mammals is revealed. In conjugation with newer and faster techniques like high-throughput sequencing, DNA barcoding can serve as an effective modern tool in marine biodiversity assessment and conservation.
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Affiliation(s)
- Subrata Trivedi
- Department of Biology, Faculty of Science, University of Tabuk, Tabuk 71491, Saudi Arabia
| | - Abdulhadi A. Aloufi
- Department of Biology, Faculty of Science, University of Tabuk, Tabuk 71491, Saudi Arabia
| | - Abid A. Ansari
- Department of Biology, Faculty of Science, University of Tabuk, Tabuk 71491, Saudi Arabia
| | - Sankar K. Ghosh
- Department of Biotechnology, Assam University, Silchar 788011, Assam, India
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15
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A new heart for a new head in vertebrate cardiopharyngeal evolution. Nature 2015; 520:466-73. [PMID: 25903628 DOI: 10.1038/nature14435] [Citation(s) in RCA: 157] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Accepted: 11/25/2014] [Indexed: 12/22/2022]
Abstract
It has been more than 30 years since the publication of the new head hypothesis, which proposed that the vertebrate head is an evolutionary novelty resulting from the emergence of neural crest and cranial placodes. Neural crest generates the skull and associated connective tissues, whereas placodes produce sensory organs. However, neither crest nor placodes produce head muscles, which are a crucial component of the complex vertebrate head. We discuss emerging evidence for a surprising link between the evolution of head muscles and chambered hearts - both systems arise from a common pool of mesoderm progenitor cells within the cardiopharyngeal field of vertebrate embryos. We consider the origin of this field in non-vertebrate chordates and its evolution in vertebrates.
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16
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Regulation and evolution of cardiopharyngeal cell identity and behavior: insights from simple chordates. Curr Opin Genet Dev 2015; 32:119-28. [PMID: 25819888 DOI: 10.1016/j.gde.2015.02.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 02/16/2015] [Accepted: 02/23/2015] [Indexed: 01/08/2023]
Abstract
The vertebrate heart arises from distinct first and second heart fields. The latter also share a common origin with branchiomeric muscles in the pharyngeal mesoderm and transcription regulators, such as Nkx2-5, Tbx1 and Islet1. Despite significant progress, the complexity of vertebrate embryos has hindered the identification of multipotent cardiopharyngeal progenitors. Here, we summarize recent insights in cardiopharyngeal development gained from ascidian models, among the closest relatives to vertebrates. In a simplified cellular context, progressive fate specification of the ascidian cardiopharyngeal precursors presents striking similarities with their vertebrate counterparts. Multipotent cardiopharyngeal progenitors are primed to activate both the early cardiac and pharyngeal muscles programs, which segregate following asymmetric cells divisions as a result of regulatory cross-antagonisms involving Tbx1 and Nkx2-5 homologs. Activation of Ebf in pharyngeal muscle founder cells triggers both Myogenic Regulatory Factor-associated differentiation and Notch-mediated maintenance of an undifferentiated state in distinct precursors. Cross-species comparisons revealed the deep conservation of the cardiopharyngeal developmental sequence in spite of extreme genome sequence divergence, gene network rewiring and specific morphogenetic differences. Finally, analyses are beginning to uncover the influence of surrounding tissues in determining cardiopharyngeal cell identity and behavior. Thus, ascidian embryos offer a unique opportunity to study gene regulation and cell behaviors at the cellular level throughout cardiopharyngeal morphogenesis and evolution.
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17
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Abstract
The developmental paths that lead to the formation of skeletal muscles in the head are distinct from those operating in the trunk. Craniofacial muscles are associated with head and neck structures. In the embryo, these structures derive from distinct mesoderm populations. Distinct genetic programs regulate different groups of muscles within the head to generate diverse muscle specifications. Developmental and lineage studies in vertebrates and invertebrates demonstrated an overlap in progenitor populations derived from the pharyngeal mesoderm that contribute to certain head muscles and the heart. These studies reveal that the genetic program controlling pharyngeal muscles overlaps with that of the heart. Indeed cardiac and craniofacial birth defects are often linked. Recent studies suggest that early chordates, the last common ancestor of tunicates and vertebrates, had an ancestral pharyngeal mesoderm lineage that later during evolution gave rise to both heart and craniofacial structures. This chapter summarizes studies related to the origins, signaling, genetics, and evolution of the head musculature, highlighting its heterogeneous characteristics in all these aspects.
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Affiliation(s)
- Eldad Tzahor
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, 76100, Israel,
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18
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Gline S, Kaplan N, Bernadskaya Y, Abdu Y, Christiaen L. Surrounding tissues canalize motile cardiopharyngeal progenitors towards collective polarity and directed migration. Development 2015; 142:544-54. [PMID: 25564651 DOI: 10.1242/dev.115444] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Collectively migrating cells maintain group polarity and interpret external cues to reach their destination. The cardiogenic progenitors (also known as trunk ventral cells, TVCs) of the ascidian Ciona intestinalis provide a simple chordate model with which to study collective migration. Bilateral pairs of associated TVCs undergo a stereotyped polarized migration away from the tail towards the ventral trunk, arguably constituting the simplest possible example of directed collective migration. To identify tissues contributing to TVC polarity and migration, we quantified the contact between TVCs and surrounding tissues, and blocked the secretory pathway in a tissue-specific manner. Even though TVCs normally migrate as an invariably determined leader-trailer polarized pair of adherent cells, they are capable of migrating individually, albeit a shorter distance and with altered morphology. The mesenchyme contacts newborn TVCs and contributes to robust specification of the trailer but appears to have only minor effects on directed migration. The notochord does not contact the TVCs but contributes to the onset of migration. The trunk endoderm first contacts the leader TVC, then 'encases' both migrating cells and provides the inputs maintaining leader-trailer polarity. Migrating TVCs adhere to the epidermis and need this contact for their cohesion. These phenomenological studies reveal that inherently motile cardiopharyngeal progenitors are channeled into stereotyped behaviors by interactions with surrounding tissues.
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Affiliation(s)
- Stephanie Gline
- Center for Developmental Genetics, Department of Biology, New York University, NY 10003, USA
| | - Nicole Kaplan
- Center for Developmental Genetics, Department of Biology, New York University, NY 10003, USA
| | - Yelena Bernadskaya
- Center for Developmental Genetics, Department of Biology, New York University, NY 10003, USA
| | - Yusuff Abdu
- Center for Developmental Genetics, Department of Biology, New York University, NY 10003, USA
| | - Lionel Christiaen
- Center for Developmental Genetics, Department of Biology, New York University, NY 10003, USA
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19
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Veeman M, Reeves W. Quantitative and in toto imaging in ascidians: working toward an image-centric systems biology of chordate morphogenesis. Genesis 2015; 53:143-59. [PMID: 25262824 PMCID: PMC4378666 DOI: 10.1002/dvg.22828] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 08/20/2014] [Accepted: 09/25/2014] [Indexed: 12/16/2022]
Abstract
Developmental biology relies heavily on microscopy to image the finely controlled cell behaviors that drive embryonic development. Most embryos are large enough that a field of view with the resolution and magnification needed to resolve single cells will not span more than a small region of the embryo. Ascidian embryos, however, are sufficiently small that they can be imaged in toto with fine subcellular detail using conventional microscopes and objectives. Unlike other model organisms with particularly small embryos, ascidians have a chordate embryonic body plan that includes a notochord, hollow dorsal neural tube, heart primordium and numerous other anatomical details conserved with the vertebrates. Here we compare the size and anatomy of ascidian embryos with those of more traditional model organisms, and relate these features to the capabilities of both conventional and exotic imaging methods. We review the emergence of Ciona and related ascidian species as model organisms for a new era of image-based developmental systems biology. We conclude by discussing some important challenges in ascidian imaging and image analysis that remain to be solved.
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Affiliation(s)
- Michael Veeman
- Division of Biology, Kansas State University, Manhattan KS, USA
| | - Wendy Reeves
- Division of Biology, Kansas State University, Manhattan KS, USA
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20
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Griggio F, Voskoboynik A, Iannelli F, Justy F, Tilak MK, Turon X, Xavier T, Pesole G, Douzery EJP, Mastrototaro F, Gissi C. Ascidian mitogenomics: comparison of evolutionary rates in closely related taxa provides evidence of ongoing speciation events. Genome Biol Evol 2014; 6:591-605. [PMID: 24572017 PMCID: PMC3971592 DOI: 10.1093/gbe/evu041] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Ascidians are a fascinating group of filter-feeding marine chordates characterized by rapid evolution of both sequences and structure of their nuclear and mitochondrial genomes. Moreover, they include several model organisms used to investigate complex biological processes in chordates. To study the evolutionary dynamics of ascidians at short phylogenetic distances, we sequenced 13 new mitogenomes and analyzed them, together with 15 other available mitogenomes, using a novel approach involving detailed whole-mitogenome comparisons of conspecific and congeneric pairs. The evolutionary rate was quite homogeneous at both intraspecific and congeneric level, and the lowest congeneric rates were found in cryptic (morphologically undistinguishable) and in morphologically very similar species pairs. Moreover, congeneric nonsynonymous rates (dN) were up to two orders of magnitude higher than in intraspecies pairs. Overall, a clear-cut gap sets apart conspecific from congeneric pairs. These evolutionary peculiarities allowed easily identifying an extraordinary intraspecific variability in the model ascidian Botryllus schlosseri, where most pairs show a dN value between that observed at intraspecies and congeneric level, yet consistently lower than that of the Ciona intestinalis cryptic species pair. These data suggest ongoing speciation events producing genetically distinct B. schlosseri entities. Remarkably, these ongoing speciation events were undetectable by the cox1 barcode fragment, demonstrating that, at low phylogenetic distances, the whole mitogenome has a higher resolving power than cox1. Our study shows that whole-mitogenome comparative analyses, performed on a suitable sample of congeneric and intraspecies pairs, may allow detecting not only cryptic species but also ongoing speciation events.
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Affiliation(s)
- Francesca Griggio
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy
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21
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Devine WP, Wythe JD, George M, Koshiba-Takeuchi K, Bruneau BG. Early patterning and specification of cardiac progenitors in gastrulating mesoderm. eLife 2014; 3:e03848. [PMID: 25296024 PMCID: PMC4356145 DOI: 10.7554/elife.03848] [Citation(s) in RCA: 160] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 10/07/2014] [Indexed: 12/20/2022] Open
Abstract
Mammalian heart development requires precise allocation of cardiac progenitors. The existence of a multipotent progenitor for all anatomic and cellular components of the heart has been predicted but its identity and contribution to the two cardiac progenitor 'fields' has remained undefined. Here we show, using clonal genetic fate mapping, that Mesp1+ cells in gastrulating mesoderm are rapidly specified into committed cardiac precursors fated for distinct anatomic regions of the heart. We identify Smarcd3 as a marker of early specified cardiac precursors and identify within these precursors a compartment boundary at the future junction of the left and right ventricles that arises prior to morphogenesis. Our studies define the timing and hierarchy of cardiac progenitor specification and demonstrate that the cellular and anatomical fate of mesoderm-derived cardiac cells is specified very early. These findings will be important to understand the basis of congenital heart defects and to derive cardiac regeneration strategies.
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Affiliation(s)
- W Patrick Devine
- Gladstone Institute of Cardiovascular Disease, San Francisco, United States
- Roddenberry Center for Stem Cell Biology and Medicine at Gladstone, San Francisco, United States
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, United States
- Department of Pathology, University of California, San Francisco, San Francisco, United States
| | - Joshua D Wythe
- Gladstone Institute of Cardiovascular Disease, San Francisco, United States
- Roddenberry Center for Stem Cell Biology and Medicine at Gladstone, San Francisco, United States
| | - Matthew George
- Gladstone Institute of Cardiovascular Disease, San Francisco, United States
- Roddenberry Center for Stem Cell Biology and Medicine at Gladstone, San Francisco, United States
- Developmental and Stem Cell Biology Program, University of San Francisco, San Francisco, United States
| | - Kazuko Koshiba-Takeuchi
- Gladstone Institute of Cardiovascular Disease, San Francisco, United States
- Roddenberry Center for Stem Cell Biology and Medicine at Gladstone, San Francisco, United States
| | - Benoit G Bruneau
- Gladstone Institute of Cardiovascular Disease, San Francisco, United States
- Roddenberry Center for Stem Cell Biology and Medicine at Gladstone, San Francisco, United States
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, United States
- Developmental and Stem Cell Biology Program, University of San Francisco, San Francisco, United States
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22
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Stolfi A, Lowe EK, Racioppi C, Ristoratore F, Brown CT, Swalla BJ, Christiaen L. Divergent mechanisms regulate conserved cardiopharyngeal development and gene expression in distantly related ascidians. eLife 2014; 3:e03728. [PMID: 25209999 PMCID: PMC4356046 DOI: 10.7554/elife.03728] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 09/05/2014] [Indexed: 12/13/2022] Open
Abstract
Ascidians present a striking dichotomy between conserved phenotypes and divergent genomes: embryonic cell lineages and gene expression patterns are conserved between distantly related species. Much research has focused on Ciona or Halocynthia spp. but development in other ascidians remains poorly characterized. In this study, we surveyed the multipotent myogenic B7.5 lineage in Molgula spp. Comparisons to the homologous lineage in Ciona revealed identical cell division and fate specification events that result in segregation of larval, cardiac, and pharyngeal muscle progenitors. Moreover, the expression patterns of key regulators are conserved, but cross-species transgenic assays uncovered incompatibility, or ‘unintelligibility’, of orthologous cis-regulatory sequences between Molgula and Ciona. These sequences drive identical expression patterns that are not recapitulated in cross-species assays. We show that this unintelligibility is likely due to changes in both cis- and trans-acting elements, hinting at widespread and frequent turnover of regulatory mechanisms underlying otherwise conserved aspects of ascidian embryogenesis. DOI:http://dx.doi.org/10.7554/eLife.03728.001 When two species have features that look similar, this may be because the features arise by the same processes during development. Other features may look similar yet develop by different mechanisms. ‘Developmental system drift’ refers to the process where a physical feature remains unaltered during evolution, but the underlying pathway that controls its development is changed. However, to date, there have been only a few experimental studies that support this idea. Ascidians—also commonly known as sea squirts—are vase-like marine creatures, which start off as tadpole-like larvae that swim around until they find a place to settle down and attach themselves. Once attached, the sea squirts lose the ability to swim and start feeding, typically by filtering material out of the seawater. Sea squirts and their close relatives are the invertebrates (animals without backbones) that are most closely related to all vertebrates (animals with backbones), including humans. Furthermore, although different species of sea squirt have almost identical embryos, their genomes are very different. Stolfi et al. have now studied whether developmental system drift may have occurred during the evolution of ascidians, by analyzing different species of sea squirt named Molgula and Ciona. Stolfi et al. compared the genomes of Molgula and Ciona and studied the expression of genes in the cells that give rise to the heart and the muscles of the head. As an embryo develops, specific genes are switched on or off, and these patterns of gene activation were broadly identical in the two species of sea squirt examined. Enhancers are sequences of DNA that control when and how a gene is switched on. Given the similarities between the development of heart and head muscle cells in the different sea squirts, Stolfi et al. looked to see if the mechanisms of gene expression, and therefore the enhancers, were also conserved. Unexpectedly, this was not the case. When enhancers from Molgula were introduced into Ciona (and vice versa), these sequences were unable to switch on gene expression—thus enhancers from one sea squirt species could not function in the other. Stolfi et al. conclude that the developmental systems may have drifted considerably during evolution of the sea squirts, in spite of their nearly identical embryos. This reinforces the view that different paths can lead to the formation of similar physical features. DOI:http://dx.doi.org/10.7554/eLife.03728.002
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Affiliation(s)
- Alberto Stolfi
- Center for Developmental Genetics, Department of Biology, New York University, New York, United States
| | - Elijah K Lowe
- Department of Computer Science and Engineering, Michigan State University, East Lansing, United States
| | - Claudia Racioppi
- Cellular and Developmental Biology Laboratory, Stazione Zoologica Anton Dohrn, Napoli, Italy
| | - Filomena Ristoratore
- Cellular and Developmental Biology Laboratory, Stazione Zoologica Anton Dohrn, Napoli, Italy
| | - C Titus Brown
- Department of Computer Science and Engineering, Michigan State University, East Lansing, United States
| | - Billie J Swalla
- Department of Biology, University of Washington, Seattle, United States
| | - Lionel Christiaen
- Center for Developmental Genetics, Department of Biology, New York University, New York, United States
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23
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Razy-Krajka F, Lam K, Wang W, Stolfi A, Joly M, Bonneau R, Christiaen L. Collier/OLF/EBF-dependent transcriptional dynamics control pharyngeal muscle specification from primed cardiopharyngeal progenitors. Dev Cell 2014; 29:263-76. [PMID: 24794633 DOI: 10.1016/j.devcel.2014.04.001] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 01/26/2014] [Accepted: 04/01/2014] [Indexed: 01/09/2023]
Abstract
In vertebrates, pluripotent pharyngeal mesoderm progenitors produce the cardiac precursors of the second heart field as well as the branchiomeric head muscles and associated stem cells. However, the mechanisms underlying the transition from multipotent progenitors to distinct muscle precursors remain obscured by the complexity of vertebrate embryos. Using Ciona intestinalis as a simple chordate model, we show that bipotent cardiopharyngeal progenitors are primed to activate both heart and pharyngeal muscle transcriptional programs, which progressively become restricted to corresponding precursors. The transcription factor COE (Collier/OLF/EBF) orchestrates the transition to pharyngeal muscle fate both by promoting an MRF-associated myogenic program in myoblasts and by maintaining an undifferentiated state in their sister cells through Notch-mediated lateral inhibition. The latter are stem cell-like muscle precursors that form most of the juvenile pharyngeal muscles. We discuss the implications of our findings for the development and evolution of the chordate cardiopharyngeal mesoderm.
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Affiliation(s)
- Florian Razy-Krajka
- Center for Developmental Genetics, Department of Biology, New York University, New York, NY 10003, USA
| | - Karen Lam
- Center for Developmental Genetics, Department of Biology, New York University, New York, NY 10003, USA; Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY 10003, USA; Courant Institute of Mathematical Sciences, New York University, New York, NY 10012, USA
| | - Wei Wang
- Center for Developmental Genetics, Department of Biology, New York University, New York, NY 10003, USA
| | - Alberto Stolfi
- Center for Developmental Genetics, Department of Biology, New York University, New York, NY 10003, USA
| | - Marine Joly
- Center for Developmental Genetics, Department of Biology, New York University, New York, NY 10003, USA
| | - Richard Bonneau
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY 10003, USA; Courant Institute of Mathematical Sciences, New York University, New York, NY 10012, USA
| | - Lionel Christiaen
- Center for Developmental Genetics, Department of Biology, New York University, New York, NY 10003, USA.
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24
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Wang W, Razy-Krajka F, Siu E, Ketcham A, Christiaen L. NK4 antagonizes Tbx1/10 to promote cardiac versus pharyngeal muscle fate in the ascidian second heart field. PLoS Biol 2013; 11:e1001725. [PMID: 24311985 PMCID: PMC3849182 DOI: 10.1371/journal.pbio.1001725] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 10/23/2013] [Indexed: 12/27/2022] Open
Abstract
Cross inhibition between NK4 and TBX1 transcription factors specifies heart versus pharyngeal muscle fates by promoting the activation of tissue-specific regulators in distinct precursors within the cardiopharyngeal lineage of the ascidian, Ciona intestinalis. The heart and head muscles share common developmental origins and genetic underpinnings in vertebrates, including humans. Parts of the heart and cranio-facial musculature derive from common mesodermal progenitors that express NKX2-5, ISL1, and TBX1. This ontogenetic kinship is dramatically reflected in the DiGeorge/Cardio-Velo-Facial syndrome (DGS/CVFS), where mutations of TBX1 cause malformations in the pharyngeal apparatus and cardiac outflow tract. Cardiac progenitors of the first heart field (FHF) do not require TBX1 and segregate precociously from common progenitors of the second heart field (SHF) and pharyngeal muscles. However, the cellular and molecular mechanisms that govern heart versus pharyngeal muscle specification within this lineage remain elusive. Here, we harness the simplicity of the ascidian larva to show that, following asymmetric cell division of common progenitors, NK4/NKX2-5 promotes GATAa/GATA4/5/6 expression and cardiac specification in the second heart precursors by antagonizing Tbx1/10-mediated inhibition of GATAa and activation of Collier/Olf/EBF (COE), the determinant of atrial siphon muscle (ASM) specification. Our results uncover essential regulatory connections between the conserved cardio-pharyngeal factor Tbx1/10 and muscle determinant COE, as well as a mutual antagonism between NK4 and Tbx1/10 activities upstream of GATAa and COE. The latter cross-antagonism underlies a fundamental heart versus pharyngeal muscle fate choice that occurs in a conserved lineage of cardio-pharyngeal progenitors. We propose that this basic ontogenetic motif underlies cardiac and pharyngeal muscle development and evolution in chordates. Mutations in the regulatory genes encoding the transcription factors NKX2-5 and TBX1, which govern heart and head muscle development, cause prevalent congenital defects. Recent studies using vertebrate models have shown that the heart and pharyngeal head muscle cells derive from common progenitors in the early embryo. To better understand the genetic mechanisms by which these progenitors select one of the two developmental trajectories, we studied the activity of these transcription factors in a simple invertebrate chordate model, the sea squirt Ciona intestinalis. We show that the sea squirt homolog of NKX2-5 promotes early heart specification by inhibiting the formation of pharyngeal muscles. Conversely, the TBX1 homolog determines pharyngeal muscle fate by inhibiting GATAa and thereby the heart program it instructs, as well as promoting the pharyngeal muscle program through activation of COE (Collier/Olf-1/EBF), a recently identified regulator of skeletal muscle differentiation. Finally, we show that the NKX2-5 homolog protein directly binds to the COE gene to repress its activity. Notably, these antagonistic interactions occur in heart and pharyngeal precursors immediately following the division of their pluripotent mother cells, thus contributing to their respective fate choice. These mechanistic insights into the process of early heart versus head muscle specification in this simple chordate provide the grounds for establishing the etiology of human congenital cardio-craniofacial defects.
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Affiliation(s)
- Wei Wang
- Department of Biology, New York University, New York, New York, United States of America
| | - Florian Razy-Krajka
- Department of Biology, New York University, New York, New York, United States of America
| | - Eric Siu
- Department of Biology, New York University, New York, New York, United States of America
| | - Alexandra Ketcham
- Department of Biology, New York University, New York, New York, United States of America
| | - Lionel Christiaen
- Department of Biology, New York University, New York, New York, United States of America
- * E-mail:
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25
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Boukhatmi H, Frendo JL, Enriquez J, Crozatier M, Dubois L, Vincent A. Tup/Islet1 integrates time and position to specify muscle identity in Drosophila. Development 2012; 139:3572-82. [DOI: 10.1242/dev.083410] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The LIM-homeodomain transcription factor Tailup/Islet1 (Tup) is a key component of cardiogenesis in Drosophila and vertebrates. We report here an additional major role for Drosophila Tup in specifying dorsal muscles. Tup is expressed in the four dorsal muscle progenitors (PCs) and tup-null embryos display a severely disorganized dorsal musculature, including a transformation of the dorsal DA2 into dorsolateral DA3 muscle. This transformation is reciprocal to the DA3 to DA2 transformation observed in collier (col) mutants. The DA2 PC, which gives rise to the DA2 muscle and to an adult muscle precursor, is selected from a cluster of myoblasts transiently expressing both Tinman (Tin) and Col. The activation of tup by Tin in the DA2 PC is required to repress col transcription and establish DA2 identity. The transient, partial overlap between Tin and Col expression provides a window of opportunity to distinguish between DA2 and DA3 muscle identities. The function of Tup in the DA2 PC illustrates how single cell precision can be reached in cell specification when temporal dynamics are combined with positional information. The contributions of Tin, Tup and Col to patterning Drosophila dorsal muscles bring novel parallels with chordate pharyngeal muscle development.
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Affiliation(s)
- Hadi Boukhatmi
- Université de Toulouse 3, Centre de Biologie du Développement, UMR 5547 CNRS and FRBT, 118 route de Narbonne, F-31062 Toulouse cedex 09, France
| | - Jean Louis Frendo
- Université de Toulouse 3, Centre de Biologie du Développement, UMR 5547 CNRS and FRBT, 118 route de Narbonne, F-31062 Toulouse cedex 09, France
| | - Jonathan Enriquez
- Université de Toulouse 3, Centre de Biologie du Développement, UMR 5547 CNRS and FRBT, 118 route de Narbonne, F-31062 Toulouse cedex 09, France
| | - Michèle Crozatier
- Université de Toulouse 3, Centre de Biologie du Développement, UMR 5547 CNRS and FRBT, 118 route de Narbonne, F-31062 Toulouse cedex 09, France
| | - Laurence Dubois
- Université de Toulouse 3, Centre de Biologie du Développement, UMR 5547 CNRS and FRBT, 118 route de Narbonne, F-31062 Toulouse cedex 09, France
| | - Alain Vincent
- Université de Toulouse 3, Centre de Biologie du Développement, UMR 5547 CNRS and FRBT, 118 route de Narbonne, F-31062 Toulouse cedex 09, France
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