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Jourdeuil K, Neilson KM, Cousin H, Tavares ALP, Majumdar HD, Alfandari D, Moody SA. Zmym4 is required for early cranial gene expression and craniofacial cartilage formation. Front Cell Dev Biol 2023; 11:1274788. [PMID: 37854072 PMCID: PMC10579616 DOI: 10.3389/fcell.2023.1274788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 09/18/2023] [Indexed: 10/20/2023] Open
Abstract
Introduction: The Six1 transcription factor plays important roles in the development of cranial sensory organs, and point mutations underlie craniofacial birth defects. Because Six1's transcriptional activity can be modulated by interacting proteins, we previously screened for candidate interactors and identified zinc-finger MYM-containing protein 4 (Zmym4) by its inclusion of a few domains with a bona fide cofactor, Sine oculis binding protein (Sobp). Although Zmym4 has been implicated in regulating early brain development and certain cancers, its role in craniofacial development has not previously been described. Methods: We used co-immunoprecipitation and luciferase-reporter assays in cultured cells to test interactions between Zmym4 and Six1. We used knock-down and overexpression of Zmym4 in embryos to test for its effects on early ectodermal gene expression, neural crest migration and craniofacial cartilage formation. Results: We found no evidence that Zmym4 physically or transcriptionally interacts with Six1 in cultured cells. Nonetheless, knockdown of endogenous Zmym4 in embryos resulted in altered early cranial gene expression, including those expressed in the neural border, neural plate, neural crest and preplacodal ectoderm. Experimentally increasing Zmym4 levels had minor effects on neural border or neural plate genes, but altered the expression of neural crest and preplacodal genes. At larval stages, genes expressed in the otic vesicle and branchial arches showed reduced expression in Zmym4 morphants. Although we did not detect defects in neural crest migration into the branchial arches, loss of Zmym4 resulted in aberrant morphology of several craniofacial cartilages. Discussion: Although Zmym4 does not appear to function as a Six1 transcriptional cofactor, it plays an important role in regulating the expression of embryonic cranial genes in tissues critical for normal craniofacial development.
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Affiliation(s)
- Karyn Jourdeuil
- Department of Anatomy and Cell Biology, George Washington University, School of Medicine and Health Sciences, Washington, DC, United States
| | - Karen M. Neilson
- Department of Anatomy and Cell Biology, George Washington University, School of Medicine and Health Sciences, Washington, DC, United States
| | - Helene Cousin
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, MA, United States
| | - Andre L. P. Tavares
- Department of Anatomy and Cell Biology, George Washington University, School of Medicine and Health Sciences, Washington, DC, United States
| | - Himani D. Majumdar
- Department of Anatomy and Cell Biology, George Washington University, School of Medicine and Health Sciences, Washington, DC, United States
| | - Dominique Alfandari
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, MA, United States
| | - Sally A. Moody
- Department of Anatomy and Cell Biology, George Washington University, School of Medicine and Health Sciences, Washington, DC, United States
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Baxi A, Jourdeuil K, Cox TC, Clouthier DE, Tavares ALP. Transcriptomic analysis reveals the role of SIX1 in mouse cranial neural crest patterning and bone development. Dev Dyn 2023; 252:1303-1315. [PMID: 37183792 PMCID: PMC10592572 DOI: 10.1002/dvdy.597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/19/2023] [Accepted: 04/24/2023] [Indexed: 05/16/2023] Open
Abstract
BACKGROUND Genetic variants of the transcription factor SIX1 and its co-factor EYA1 underlie 50% of Branchio-oto-renal syndrome (BOR) cases. BOR is characterized by craniofacial defects, including malformed middle ear ossicles leading to conductive hearing loss. In this work, we expand our knowledge of the Six1 gene regulatory network by using a Six1-null mouse line to assess gene expression profiles of E10.5 mandibular arches, which give rise to the neural crest (NC)-derived middle ear ossicles and lower jaw, via bulk RNA sequencing. RESULTS Our transcriptomic analysis led to the identification of 808 differentially expressed genes that are related to translation, NC cell differentiation, osteogenesis, and chondrogenesis including components of the WNT signaling pathway. As WNT signaling is a known contributor to bone development, we demonstrated that SIX1 is required for expression of the WNT antagonist Frzb in the mandibular arch, and determined that SIX1 expression results in repression of WNT signaling. CONCLUSION Our results clarify the mechanisms by which SIX1 regulates the development of NC-derived craniofacial elements that are altered in SIX1-associated disorders. In addition, this work identifies novel genes that could be causative to this birth defect and establishes a link between SIX1 and WNT signaling during patterning of NC cells.
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Affiliation(s)
- Aparna Baxi
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington DC, DC 20037, USA
| | - Karyn Jourdeuil
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington DC, DC 20037, USA
| | - Timothy C. Cox
- Departments of Oral and Craniofacial Sciences and Pediatrics, University of Missouri-Kansas City, Kansas City, MO 64108, USA
| | - David E. Clouthier
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Andre L. P. Tavares
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington DC, DC 20037, USA
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Keer S, Cousin H, Jourdeuil K, Neilson KM, Tavares ALP, Alfandari D, Moody SA. Mcrs1 is required for branchial arch and cranial cartilage development. Dev Biol 2022; 489:62-75. [PMID: 35697116 PMCID: PMC10426812 DOI: 10.1016/j.ydbio.2022.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 06/06/2022] [Accepted: 06/08/2022] [Indexed: 11/22/2022]
Abstract
Mcrs1 is a multifunctional protein that is critical for many cellular processes in a wide range of cell types. Previously, we showed that Mcrs1 binds to the Six1 transcription factor and reduces the ability of the Six1-Eya1 complex to upregulate transcription, and that Mcrs1 loss-of-function leads to the expansion of several neural plate genes, reduction of neural border and pre-placodal ectoderm (PPR) genes, and pleiotropic effects on various neural crest (NC) genes. Because the affected embryonic structures give rise to several of the cranial tissues affected in Branchio-otic/Branchio-oto-renal (BOR) syndrome, herein we tested whether these gene expression changes subsequently alter the development of the proximate precursors of BOR affected structures - the otic vesicles (OV) and branchial arches (BA). We found that Mcrs1 is required for the expression of several OV genes involved in inner ear formation, patterning and otic capsule cartilage formation. Mcrs1 knockdown also reduced the expression domains of many genes expressed in the larval BA, derived from either NC or PPR, except for emx2, which was expanded. Reduced Mcrs1 also diminished the length of the expression domain of tbx1 in BA1 and BA2 and interfered with cranial NC migration from the dorsal neural tube; this subsequently resulted in defects in the morphology of lower jaw cartilages derived from BA1 and BA2, including the infrarostral, Meckel's, and ceratohyal as well as the otic capsule. These results demonstrate that Mcrs1 plays an important role in processes that lead to the formation of craniofacial cartilages and its loss results in phenotypes consistent with reduced Six1 activity associated with BOR.
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Affiliation(s)
- Stephanie Keer
- Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, 2300 I (eye) Street, NW, Washington, DC, 20037, USA
| | - Helene Cousin
- Department of Animal Science, University of Massachusetts Amherst, Integrated Science Building, 661 N. Pleasant Street, Amherst, MA, 01003, USA
| | - Karyn Jourdeuil
- Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, 2300 I (eye) Street, NW, Washington, DC, 20037, USA
| | - Karen M Neilson
- Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, 2300 I (eye) Street, NW, Washington, DC, 20037, USA
| | - Andre L P Tavares
- Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, 2300 I (eye) Street, NW, Washington, DC, 20037, USA
| | - Dominique Alfandari
- Department of Animal Science, University of Massachusetts Amherst, Integrated Science Building, 661 N. Pleasant Street, Amherst, MA, 01003, USA
| | - Sally A Moody
- Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, 2300 I (eye) Street, NW, Washington, DC, 20037, USA.
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Klein SL, Tavares ALP, Peterson M, Sullivan CH, Moody SA. Repressive Interactions Between Transcription Factors Separate Different Embryonic Ectodermal Domains. Front Cell Dev Biol 2022; 10:786052. [PMID: 35198557 PMCID: PMC8859430 DOI: 10.3389/fcell.2022.786052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 01/10/2022] [Indexed: 11/13/2022] Open
Abstract
The embryonic ectoderm is composed of four domains: neural plate, neural crest, pre-placodal region (PPR) and epidermis. Their formation is initiated during early gastrulation by dorsal-ventral and anterior-posterior gradients of signaling factors that first divide the embryonic ectoderm into neural and non-neural domains. Next, the neural crest and PPR domains arise, either via differential competence of the neural and non-neural ectoderm (binary competence model) or via interactions between the neural and non-neural ectoderm tissues to produce an intermediate neural border zone (NB) (border state model) that subsequently separates into neural crest and PPR. Many previous gain- and loss-of-function experiments demonstrate that numerous TFs are expressed in initially overlapping zones that gradually resolve into patterns that by late neurula stages are characteristic of each of the four domains. Several of these studies suggested that this is accomplished by a combination of repressive TF interactions and competence to respond to local signals. In this study, we ectopically expressed TFs that at neural plate stages are characteristic of one domain in a different domain to test whether they act cell autonomously as repressors. We found that almost all tested TFs caused reduced expression of the other TFs. At gastrulation these effects were strictly within the lineage-labeled cells, indicating that the effects were cell autonomous, i.e., due to TF interactions within individual cells. Analysis of previously published single cell RNAseq datasets showed that at the end of gastrulation, and continuing to neural tube closure stages, many ectodermal cells express TFs characteristic of more than one neural plate stage domain, indicating that different TFs have the opportunity to interact within the same cell. At neurula stages repression was observed both in the lineage-labeled cells and in adjacent cells not bearing detectable lineage label, suggesting that cell-to-cell signaling has begun to contribute to the separation of the domains. Together, these observations directly demonstrate previous suggestions in the literature that the segregation of embryonic ectodermal domains initially involves cell autonomous, repressive TF interactions within an individual cell followed by the subsequent advent of non-cell autonomous signaling to neighbors.
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Affiliation(s)
- Steven L Klein
- Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, Washington, D.C., DC, United States
| | - Andre L P Tavares
- Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, Washington, D.C., DC, United States
| | - Meredith Peterson
- Department of Biology, State College, Penn State University, University Park, PA, United States
| | | | - Sally A Moody
- Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, Washington, D.C., DC, United States
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Coppenrath K, Tavares ALP, Shaidani NI, Wlizla M, Moody SA, Horb M. Generation of a new six1-null line in Xenopus tropicalis for study of development and congenital disease. Genesis 2021; 59:e23453. [PMID: 34664392 DOI: 10.1002/dvg.23453] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 09/02/2021] [Accepted: 09/04/2021] [Indexed: 12/15/2022]
Abstract
The vertebrate Six (Sine oculis homeobox) family of homeodomain transcription factors plays critical roles in the development of several organs. Six1 plays a central role in cranial placode development, including the precursor tissues of the inner ear, as well as other cranial sensory organs and the kidney. In humans, mutations in SIX1 underlie some cases of Branchio-oto-renal (BOR) syndrome, which is characterized by moderate-to-severe hearing loss. We utilized CRISPR/Cas9 technology to establish a six1 mutant line in Xenopus tropicalis that is available to the research community. We demonstrate that at larval stages, the six1-null animals show severe disruptions in gene expression of putative Six1 target genes in the otic vesicle, cranial ganglia, branchial arch, and neural tube. At tadpole stages, six1-null animals display dysmorphic Meckel's, ceratohyal, and otic capsule cartilage morphology. This mutant line will be of value for the study of the development of several organs as well as congenital syndromes that involve these tissues.
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Affiliation(s)
- Kelsey Coppenrath
- Eugene Bell Center for Regenerative Biology and Tissue Engineering and National Xenopus Resource, Marine Biological Laboratory, Woods Hole, Massachusetts, USA
| | - Andre L P Tavares
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, District of Columbia, USA
| | - Nikko-Ideen Shaidani
- Eugene Bell Center for Regenerative Biology and Tissue Engineering and National Xenopus Resource, Marine Biological Laboratory, Woods Hole, Massachusetts, USA
| | - Marcin Wlizla
- Eugene Bell Center for Regenerative Biology and Tissue Engineering and National Xenopus Resource, Marine Biological Laboratory, Woods Hole, Massachusetts, USA.,Embryology Department, Charles River Laboratories, Wilmington, Massachusetts, USA
| | - Sally A Moody
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, District of Columbia, USA
| | - Marko Horb
- Eugene Bell Center for Regenerative Biology and Tissue Engineering and National Xenopus Resource, Marine Biological Laboratory, Woods Hole, Massachusetts, USA
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Tavares ALP, Jourdeuil K, Neilson KM, Majumdar HD, Moody SA. Sobp modulates the transcriptional activation of Six1 target genes and is required during craniofacial development. Development 2021; 148:272053. [PMID: 34414417 DOI: 10.1242/dev.199684] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 08/10/2021] [Indexed: 12/26/2022]
Abstract
Branchio-oto-renal syndrome (BOR) is a disorder characterized by hearing loss, and craniofacial and/or renal defects. Variants in the transcription factor Six1 and its co-factor Eya1, both of which are required for otic development, are linked to BOR. We previously identified Sobp as a potential Six1 co-factor, and SOBP variants in mouse and humans cause otic phenotypes; therefore, we asked whether Sobp interacts with Six1 and thereby may contribute to BOR. Co-immunoprecipitation and immunofluorescence experiments demonstrate that Sobp binds to and colocalizes with Six1 in the cell nucleus. Luciferase assays show that Sobp interferes with the transcriptional activation of Six1+Eya1 target genes. Experiments in Xenopus embryos that either knock down or increase expression of Sobp show that it is required for formation of ectodermal domains at neural plate stages. In addition, altering Sobp levels disrupts otic vesicle development and causes craniofacial cartilage defects. Expression of Xenopus Sobp containing the human variant disrupts the pre-placodal ectoderm similar to full-length Sobp, but other changes are distinct. These results indicate that Sobp modifies Six1 function and is required for vertebrate craniofacial development, and identify Sobp as a potential candidate gene for BOR.
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Affiliation(s)
- Andre L P Tavares
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington DC, DC 20037, USA
| | - Karyn Jourdeuil
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington DC, DC 20037, USA
| | - Karen M Neilson
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington DC, DC 20037, USA
| | - Himani D Majumdar
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington DC, DC 20037, USA
| | - Sally A Moody
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington DC, DC 20037, USA
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Maynard TM, Horvath A, Bernot JP, Karpinski BA, Tavares ALP, Shah A, Zheng Q, Spurr L, Olender J, Moody SA, Fraser CM, LaMantia AS, Lee NH. Transcriptional dysregulation in developing trigeminal sensory neurons in the LgDel mouse model of DiGeorge 22q11.2 deletion syndrome. Hum Mol Genet 2021; 29:1002-1017. [PMID: 32047912 PMCID: PMC7158380 DOI: 10.1093/hmg/ddaa024] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 01/12/2020] [Accepted: 02/04/2020] [Indexed: 12/13/2022] Open
Abstract
LgDel mice, which model the heterozygous deletion of genes at human chromosome 22q11.2 associated with DiGeorge/22q11.2 deletion syndrome (22q11DS), have cranial nerve and craniofacial dysfunction as well as disrupted suckling, feeding and swallowing, similar to key 22q11DS phenotypes. Divergent trigeminal nerve (CN V) differentiation and altered trigeminal ganglion (CNgV) cellular composition prefigure these disruptions in LgDel embryos. We therefore asked whether a distinct transcriptional state in a specific population of early differentiating LgDel cranial sensory neurons, those in CNgV, a major source of innervation for appropriate oropharyngeal function, underlies this departure from typical development. LgDel versus wild-type (WT) CNgV transcriptomes differ significantly at E10.5 just after the ganglion has coalesced. Some changes parallel altered proportions of cranial placode versus cranial neural crest-derived CNgV cells. Others are consistent with a shift in anterior-posterior patterning associated with divergent LgDel cranial nerve differentiation. The most robust quantitative distinction, however, is statistically verifiable increased variability of expression levels for most of the over 17 000 genes expressed in common in LgDel versus WT CNgV. Thus, quantitative expression changes of functionally relevant genes and increased stochastic variation across the entire CNgV transcriptome at the onset of CN V differentiation prefigure subsequent disruption of cranial nerve differentiation and oropharyngeal function in LgDel mice.
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Affiliation(s)
- Thomas M Maynard
- Fralin Biomedical Research Institute, Virginia Tech-Carilion School of Medicine, Roanoke, VA, 24016 USA.,Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Anelia Horvath
- Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA.,McCormick Genomics and Proteomics Center, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - James P Bernot
- Department of Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Beverly A Karpinski
- Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Andre L P Tavares
- Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Ankita Shah
- Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Qianqian Zheng
- Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Liam Spurr
- Department of Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Jacqueline Olender
- Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Sally A Moody
- Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Claire M Fraser
- Institute for Genome Sciences, University of Maryland, Baltimore, Baltimore, MD, USA
| | - Anthony-S LaMantia
- Fralin Biomedical Research Institute, Virginia Tech-Carilion School of Medicine, Roanoke, VA, 24016 USA.,Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA.,Department of Biological Sciences, College of Science, Virginia Tech, Blacksburg VA, 24061, USA.,Department of Pediatrics, Virginia Tech Carilion School of Medicine, Roanoke, VA, 24016, USA
| | - Norman H Lee
- Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
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Maynard TM, Horvath A, Bernot JP, Karpinski BA, Tavares ALP, Shah A, Zheng Q, Spurr L, Olender J, Moody SA, Fraser CM, LaMantia AS, Lee NH. Transcriptional dysregulation in developing trigeminal sensory neurons in the LgDel mouse model of DiGeorge 22q11.2 deletion syndrome. Hum Mol Genet 2020; 29:1580. [PMID: 32358605 PMCID: PMC7268547 DOI: 10.1093/hmg/ddaa067] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- Thomas M Maynard
- Fralin Biomedical Research Institute, Virginia Tech-Carilion School of Medicine, Roanoke, VA, 24016 USA.,Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Anelia Horvath
- Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA.,McCormick Genomics and Proteomics Center, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - James P Bernot
- Department of Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Beverly A Karpinski
- Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Andre L P Tavares
- Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Ankita Shah
- Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Qianqian Zheng
- Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Liam Spurr
- Department of Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Jacqueline Olender
- Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Sally A Moody
- Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Claire M Fraser
- Institute for Genome Sciences, University of Maryland, Baltimore, Baltimore, MD, USA
| | - Anthony-S LaMantia
- Fralin Biomedical Research Institute, Virginia Tech-Carilion School of Medicine, Roanoke, VA, 24016 USA.,Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA.,Department of Biological Sciences, College of Science, Virginia Tech, Blacksburg VA, 24061, USA.,Department of Pediatrics, Virginia Tech Carilion School of Medicine, Roanoke, VA, 24016, USA
| | - Norman H Lee
- Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA.,Department of Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
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Pritchard AB, Kanai SM, Krock B, Schindewolf E, Oliver-Krasinski J, Khalek N, Okashah N, Lambert NA, Tavares ALP, Zackai E, Clouthier DE. Loss-of-function of Endothelin receptor type A results in Oro-Oto-Cardiac syndrome. Am J Med Genet A 2020; 182:1104-1116. [PMID: 32133772 DOI: 10.1002/ajmg.a.61531] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 02/06/2020] [Accepted: 02/06/2020] [Indexed: 01/14/2023]
Abstract
Craniofacial morphogenesis is regulated in part by signaling from the Endothelin receptor type A (EDNRA). Pathogenic variants in EDNRA signaling pathway components EDNRA, GNAI3, PCLB4, and EDN1 cause Mandibulofacial Dysostosis with Alopecia (MFDA), Auriculocondylar syndrome (ARCND) 1, 2, and 3, respectively. However, cardiovascular development is normal in MFDA and ARCND individuals, unlike Ednra knockout mice. One explanation may be that partial EDNRA signaling remains in MFDA and ARCND, as mice with reduced, but not absent, EDNRA signaling also lack a cardiovascular phenotype. Here we report an individual with craniofacial and cardiovascular malformations mimicking the Ednra -/- mouse phenotype, including a distinctive micrognathia with microstomia and a hypoplastic aortic arch. Exome sequencing found a novel homozygous missense variant in EDNRA (c.1142A>C; p.Q381P). Bioluminescence resonance energy transfer assays revealed that this amino acid substitution in helix 8 of EDNRA prevents recruitment of G proteins to the receptor, abrogating subsequent receptor activation by its ligand, Endothelin-1. This homozygous variant is thus the first reported loss-of-function EDNRA allele, resulting in a syndrome we have named Oro-Oto-Cardiac Syndrome. Further, our results illustrate that EDNRA signaling is required for both normal human craniofacial and cardiovascular development, and that limited EDNRA signaling is likely retained in ARCND and MFDA individuals. This work illustrates a straightforward approach to identifying the functional consequence of novel genetic variants in signaling molecules associated with malformation syndromes.
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Affiliation(s)
- Amanda Barone Pritchard
- Division of Human Genetics, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Stanley M Kanai
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Bryan Krock
- Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Erica Schindewolf
- Center for Fetal Diagnosis and Treatment, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | | | - Nahla Khalek
- Center for Fetal Diagnosis and Treatment, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Najeah Okashah
- Department of Pharmacology and Toxicology, Medical College of Georgia-Augusta University, Augusta, Georgia, USA
| | - Nevin A Lambert
- Department of Pharmacology and Toxicology, Medical College of Georgia-Augusta University, Augusta, Georgia, USA
| | - Andre L P Tavares
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Elaine Zackai
- Division of Human Genetics, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - David E Clouthier
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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Shah AM, Krohn P, Baxi AB, Tavares ALP, Sullivan CH, Chillakuru YR, Majumdar HD, Neilson KM, Moody SA. Six1 proteins with human branchio-oto-renal mutations differentially affect cranial gene expression and otic development. Dis Model Mech 2020; 13:dmm043489. [PMID: 31980437 PMCID: PMC7063838 DOI: 10.1242/dmm.043489] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 01/14/2020] [Indexed: 12/15/2022] Open
Abstract
Single-nucleotide mutations in human SIX1 result in amino acid substitutions in either the protein-protein interaction domain or the homeodomain, and cause ∼4% of branchio-otic (BOS) and branchio-oto-renal (BOR) cases. The phenotypic variation between patients with the same mutation, even within affected members of the same family, make it difficult to functionally distinguish between the different SIX1 mutations. We made four of the BOS/BOR substitutions in the Xenopus Six1 protein (V17E, R110W, W122R, Y129C), which is 100% identical to human in both the protein-protein interaction domain and the homeodomain, and expressed them in embryos to determine whether they cause differential changes in early craniofacial gene expression, otic gene expression or otic morphology. We confirmed that, similar to the human mutants, all four mutant Xenopus Six1 proteins access the nucleus but are transcriptionally deficient. Analysis of craniofacial gene expression showed that each mutant causes specific, often different and highly variable disruptions in the size of the domains of neural border zone, neural crest and pre-placodal ectoderm genes. Each mutant also had differential effects on genes that pattern the otic vesicle. Assessment of the tadpole inner ear demonstrated that while the auditory and vestibular structures formed, the volume of the otic cartilaginous capsule, otoliths, lumen and a subset of the hair cell-containing sensory patches were reduced. This detailed description of the effects of BOS/BOR-associated SIX1 mutations in the embryo indicates that each causes subtle changes in gene expression in the embryonic ectoderm and otocyst, leading to inner ear morphological anomalies.
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Affiliation(s)
- Ankita M Shah
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
| | - Patrick Krohn
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
- Institute of Zoology, University of Hohenheim, Stuttgart 70599, Germany
| | - Aparna B Baxi
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
| | - Andre L P Tavares
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
| | - Charles H Sullivan
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
- Department of Biology, Grinnell College, Grinnell, IA 50112, USA
| | - Yeshwant R Chillakuru
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
| | - Himani D Majumdar
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
| | - Karen M Neilson
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
| | - Sally A Moody
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
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Abstract
BACKGROUND Although normally linked to bone and cartilage development, the Runt-related transcription factor, RUNX2, was reported in the mouse heart during development of the valves. We examined RUNX2 expression and function in the developing avian heart as it related to the epithelial-mesenchymal transition (EMT) in the atrioventricular canal. EMT can be separated into an activation stage involving hypertrophy and cell separation and an invasion stage where cells invade the extracellular matrix. The localization and activity of RUNX2 was explored in relation to these steps in the heart. As RUNX2 was also reported in cancer tissues, we examined its expression in the progression of esophageal cancer in staged tissues. RESULTS A specific isoform, RUNX2-I, is present and required for EMT by endothelia of the atrioventricular canal. Knockdown of RUNX2-I inhibits the cell-cell separation that is characteristic of initial activation of EMT. Loss of RUNX2-I altered expression of EMT markers to a greater extent during activation than during subsequent cell invasion. Transforming growth factor beta 2 (TGFβ2) mediates activation during cardiac endothelial EMT. Consistent with a role in activation, RUNX2-I is regulated by TGFβ2 and its activity is independent of similarly expressed Snai2 in regulation of EMT. Examination of RUNX2 expression in esophageal cancer showed its upregulation concomitant with the development of dysplasia and continued expression in adenocarcinoma. CONCLUSIONS These data introduce the RUNX2-I isoform as a critical early transcription factor mediating EMT in the developing heart after induction by TGFβ2. Its expression in tumor tissue suggests a similar role for RUNX2 in the EMT of metastasis. Developmental Dynamics 247:542-554, 2018. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Andre L P Tavares
- Department of Craniofacial Biology, School of Dentistry, University of Colorado Anschutz Medical Campus, Denver, Colorado.,Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona
| | - Jessie A Brown
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona
| | - Emily C Ulrich
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona
| | - Katerina Dvorak
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona
| | - Raymond B Runyan
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona
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Tavares ALP, Cox TC, Maxson RM, Ford HL, Clouthier DE. Negative regulation of endothelin signaling by SIX1 is required for proper maxillary development. Development 2017; 144:2021-2031. [PMID: 28455376 DOI: 10.1242/dev.145144] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 04/18/2017] [Indexed: 12/20/2022]
Abstract
Jaw morphogenesis is a complex event mediated by inductive signals that establish and maintain the distinct developmental domains required for formation of hinged jaws, the defining feature of gnathostomes. The mandibular portion of pharyngeal arch 1 is patterned dorsally by Jagged-Notch signaling and ventrally by endothelin receptor A (EDNRA) signaling. Loss of EDNRA signaling disrupts normal ventral gene expression, the result of which is homeotic transformation of the mandible into a maxilla-like structure. However, loss of Jagged-Notch signaling does not result in significant changes in maxillary development. Here we show in mouse that the transcription factor SIX1 regulates dorsal arch development not only by inducing dorsal Jag1 expression but also by inhibiting endothelin 1 (Edn1) expression in the pharyngeal endoderm of the dorsal arch, thus preventing dorsal EDNRA signaling. In the absence of SIX1, but not JAG1, aberrant EDNRA signaling in the dorsal domain results in partial duplication of the mandible. Together, our results illustrate that SIX1 is the central mediator of dorsal mandibular arch identity, thus ensuring separation of bone development between the upper and lower jaws.
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Affiliation(s)
- Andre L P Tavares
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Timothy C Cox
- Department of Pediatrics (Craniofacial Medicine), University of Washington, and Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Robert M Maxson
- Department of Biochemistry and Molecular Biology and Norris Cancer Center, University of Southern California, Los Angeles, CA 87654, USA
| | - Heide L Ford
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - David E Clouthier
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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13
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Iklé JM, Tavares ALP, King M, Ding H, Colombo S, Firulli BA, Firulli AB, Targoff KL, Yelon D, Clouthier DE. Nkx2.5 regulates endothelin converting enzyme-1 during pharyngeal arch patterning. Genesis 2017; 55. [PMID: 28109039 DOI: 10.1002/dvg.23021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 01/16/2017] [Accepted: 01/17/2017] [Indexed: 12/11/2022]
Abstract
In gnathostomes, dorsoventral (D-V) patterning of neural crest cells (NCC) within the pharyngeal arches is crucial for the development of hinged jaws. One of the key signals that mediate this process is Endothelin-1 (EDN1). Loss of EDN1 binding to the Endothelin-A receptor (EDNRA) results in loss of EDNRA signaling and subsequent facial birth defects in humans, mice and zebrafish. A rate-limiting step in this crucial signaling pathway is the conversion of immature EDN1 into a mature active form by Endothelin converting enzyme-1 (ECE1). However, surprisingly little is known about how Ece1 transcription is induced or regulated. We show here that Nkx2.5 is required for proper craniofacial development in zebrafish and acts in part by upregulating ece1 expression. Disruption of nkx2.5 in zebrafish embryos results in defects in both ventral and dorsal pharyngeal arch-derived elements, with changes in ventral arch gene expression consistent with a disruption in Ednra signaling. ece1 mRNA rescues the nkx2.5 morphant phenotype, indicating that Nkx2.5 functions through modulating Ece1 expression or function. These studies illustrate a new function for Nkx2.5 in embryonic development and provide new avenues with which to pursue potential mechanisms underlying human facial disorders.
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Affiliation(s)
- Jennifer M Iklé
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, 80045
| | - Andre L P Tavares
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, 80045
| | - Marisol King
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, 80045
| | - Hailei Ding
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, 80045
| | - Sophie Colombo
- Division of Cardiology, Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, 10032
| | - Beth A Firulli
- Departments of Anatomy and Medical, Biochemistry, and Molecular Genetics, Indiana Medical School, Riley Heart Research Center, Herman B Wells Center for Pediatric Research, Division of Pediatric Cardiology, Indianapolis, 46202
| | - Anthony B Firulli
- Departments of Anatomy and Medical, Biochemistry, and Molecular Genetics, Indiana Medical School, Riley Heart Research Center, Herman B Wells Center for Pediatric Research, Division of Pediatric Cardiology, Indianapolis, 46202
| | - Kimara L Targoff
- Division of Cardiology, Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, 10032
| | - Deborah Yelon
- Division of Biological Sciences, University of California, San Diego, La Jolla, California, 92093
| | - David E Clouthier
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, 80045
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Tavares ALP, Artinger KB, Clouthier DE. Regulating Craniofacial Development at the 3' End: MicroRNAs and Their Function in Facial Morphogenesis. Curr Top Dev Biol 2015; 115:335-75. [PMID: 26589932 DOI: 10.1016/bs.ctdb.2015.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Defects in craniofacial development represent a majority of observed human birth defects, occurring at a rate as high as 1:800 live births. These defects often occur due to changes in neural crest cell (NCC) patterning and development and can affect non-NCC-derived structures due to interactions between NCCs and the surrounding cell types. Proper craniofacial development requires an intricate array of gene expression networks that are tightly controlled spatiotemporally by a number of regulatory mechanisms. One of these mechanisms involves the action of microRNAs (miRNAs), a class of noncoding RNAs that repress gene expression by binding to miRNA recognition sequences typically located in the 3' UTR of target mRNAs. Recent evidence illustrates that miRNAs are crucial for vertebrate facial morphogenesis, with changes in miRNA expression leading to facial birth defects, including some in complex human syndromes such as 22q11 (DiGeorge Syndrome). In this review, we highlight the current understanding of miRNA biogenesis, the roles of miRNAs in overall craniofacial development, the impact that loss of miRNAs has on normal development and the requirement for miRNAs in the development of specific craniofacial structures, including teeth. From these studies, it is clear that miRNAs are essential for normal facial development and morphogenesis, and a potential key in establishing new paradigms for repair and regeneration of facial defects.
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Affiliation(s)
- Andre L P Tavares
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Kristin B Artinger
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - David E Clouthier
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
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Clouthier DE, Passos-Bueno MR, Tavares ALP, Lyonnet S, Amiel J, Gordon CT. Understanding the basis of auriculocondylar syndrome: Insights from human, mouse and zebrafish genetic studies. Am J Med Genet C Semin Med Genet 2013; 163C:306-17. [PMID: 24123988 DOI: 10.1002/ajmg.c.31376] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Among human birth defect syndromes, malformations affecting the face are perhaps the most striking due to cultural and psychological expectations of facial shape. One such syndrome is auriculocondylar syndrome (ACS), in which patients present with defects in ear and mandible development. Affected structures arise from cranial neural crest cells, a population of cells in the embryo that reside in the pharyngeal arches and give rise to most of the bone, cartilage and connective tissue of the face. Recent studies have found that most cases of ACS arise from defects in signaling molecules associated with the endothelin signaling pathway. Disruption of this signaling pathway in both mouse and zebrafish results in loss of identity of neural crest cells of the mandibular portion of the first pharyngeal arch and the subsequent repatterning of these cells, leading to homeosis of lower jaw structures into more maxillary-like structures. These findings illustrate the importance of endothelin signaling in normal human craniofacial development and illustrate how clinical and basic science approaches can coalesce to improve our understanding of the genetic basis of human birth defect syndromes. Further, understanding the genetic basis for ACS that lies outside of known endothelin signaling components may help elucidate unknown aspects critical to the establishment of neural crest cell patterning during facial morphogenesis.
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Tavares ALP, Garcia EL, Kuhn K, Woods CM, Williams T, Clouthier DE. Ectodermal-derived Endothelin1 is required for patterning the distal and intermediate domains of the mouse mandibular arch. Dev Biol 2012; 371:47-56. [PMID: 22902530 DOI: 10.1016/j.ydbio.2012.08.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 07/18/2012] [Accepted: 08/04/2012] [Indexed: 10/28/2022]
Abstract
Morphogenesis of the vertebrate head relies on proper dorsal-ventral (D-V) patterning of neural crest cells (NCC) within the pharyngeal arches. Endothelin-1 (Edn1)-induced signaling through the endothelin-A receptor (Ednra) is crucial for cranial NCC patterning within the mandibular portion of the first pharyngeal arch, from which the lower jaw arises. Deletion of Edn1, Ednra or endothelin-converting enzyme in mice causes perinatal lethality due to severe craniofacial birth defects. These include homeotic transformation of mandibular arch-derived structures into more maxillary-like structures, indicating a loss of NCC identity. All cranial NCCs express Ednra whereas Edn1 expression is limited to the overlying ectoderm, core paraxial mesoderm and pharyngeal pouch endoderm of the mandibular arch as well as more caudal arches. To define the developmental significance of Edn1 from each of these layers, we used Cre/loxP technology to inactivate Edn1 in a tissue-specific manner. We show that deletion of Edn1 in either the mesoderm or endoderm alone does not result in cellular or molecular changes in craniofacial development. However, ectodermal deletion of Edn1 results in craniofacial defects with concomitant changes in the expression of early mandibular arch patterning genes. Importantly, our results also both define for the first time in mice an intermediate mandibular arch domain similar to the one defined in zebrafish and show that this region is most sensitive to loss of Edn1. Together, our results illustrate an integral role for ectoderm-derived Edn1 in early arch morphogenesis, particularly in the intermediate domain.
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Affiliation(s)
- Andre L P Tavares
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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