1
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Shin M, Yin HM, Shih YH, Nozaki T, Portman D, Toles B, Kolb A, Luk K, Isogai S, Ishida K, Hanasaka T, Parsons MJ, Wolfe SA, Burns CE, Burns CG, Lawson ND. Generation and application of endogenously floxed alleles for cell-specific knockout in zebrafish. Dev Cell 2023; 58:2614-2626.e7. [PMID: 37633272 PMCID: PMC10840978 DOI: 10.1016/j.devcel.2023.07.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 05/30/2023] [Accepted: 07/28/2023] [Indexed: 08/28/2023]
Abstract
The zebrafish is amenable to a variety of genetic approaches. However, lack of conditional deletion alleles limits stage- or cell-specific gene knockout. Here, we applied an existing protocol to establish a floxed allele for gata2a but failed to do so due to off-target integration and incomplete knockin. To address these problems, we applied simultaneous co-targeting with Cas12a to insert loxP sites in cis, together with transgenic counterscreening and comprehensive molecular analysis, to identify off-target insertions and confirm targeted knockins. We subsequently used our approach to establish endogenously floxed alleles of foxc1a, rasa1a, and ruvbl1, each in a single generation. We demonstrate the utility of these alleles by verifying Cre-dependent deletion, which yielded expected phenotypes in each case. Finally, we used the floxed gata2a allele to demonstrate an endothelial autonomous requirement in lymphatic valve development. Together, our results provide a framework for routine generation and application of endogenously floxed alleles in zebrafish.
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Affiliation(s)
- Masahiro Shin
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Hui-Min Yin
- Division of Basic and Translational Cardiovascular Research, Department of Cardiology, Boston Children's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Yu-Huan Shih
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Takayuki Nozaki
- Technical Support Center for Life Science Research, Iwate Medical University, Shiwa, Iwate 028-3694, Japan
| | - Daneal Portman
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Benjamin Toles
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Amy Kolb
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Kevin Luk
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Sumio Isogai
- Department of Medical Education, Iwate Medical University, Shiwa, Iwate 028-3694, Japan
| | - Kinji Ishida
- Technical Support Center for Life Science Research, Iwate Medical University, Shiwa, Iwate 028-3694, Japan
| | - Tomohito Hanasaka
- Technical Support Center for Life Science Research, Iwate Medical University, Shiwa, Iwate 028-3694, Japan
| | - Michael J Parsons
- Department of Developmental and Cell Biology, School of Biological Sciences, University of California, Irvine, Irvine, CA 92697, USA
| | - Scot A Wolfe
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Caroline E Burns
- Division of Basic and Translational Cardiovascular Research, Department of Cardiology, Boston Children's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - C Geoffrey Burns
- Division of Basic and Translational Cardiovascular Research, Department of Cardiology, Boston Children's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Nathan D Lawson
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA.
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2
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Ma RC, Kocha KM, Méndez-Olivos EE, Ruel TD, Huang P. Origin and diversification of fibroblasts from the sclerotome in zebrafish. Dev Biol 2023; 498:35-48. [PMID: 36933633 DOI: 10.1016/j.ydbio.2023.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 02/13/2023] [Accepted: 03/14/2023] [Indexed: 03/18/2023]
Abstract
Fibroblasts play an important role in maintaining tissue integrity by secreting components of the extracellular matrix and initiating response to injury. Although the function of fibroblasts has been extensively studied in adults, the embryonic origin and diversification of different fibroblast subtypes during development remain largely unexplored. Using zebrafish as a model, we show that the sclerotome, a sub-compartment of the somite, is the embryonic source of multiple fibroblast subtypes including tenocytes (tendon fibroblasts), blood vessel associated fibroblasts, fin mesenchymal cells, and interstitial fibroblasts. High-resolution imaging shows that different fibroblast subtypes occupy unique anatomical locations with distinct morphologies. Long-term Cre-mediated lineage tracing reveals that the sclerotome also contributes to cells closely associated with the axial skeleton. Ablation of sclerotome progenitors results in extensive skeletal defects. Using photoconversion-based cell lineage analysis, we find that sclerotome progenitors at different dorsal-ventral and anterior-posterior positions display distinct differentiation potentials. Single-cell clonal analysis combined with in vivo imaging suggests that the sclerotome mostly contains unipotent and bipotent progenitors prior to cell migration, and the fate of their daughter cells is biased by their migration paths and relative positions. Together, our work demonstrates that the sclerotome is the embryonic source of trunk fibroblasts as well as the axial skeleton, and local signals likely contribute to the diversification of distinct fibroblast subtypes.
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Affiliation(s)
- Roger C Ma
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, Alberta Children's Hospital Research Institute, University of Calgary, 3330 Hospital Drive, Calgary, Alberta, T2N 4N1, Canada
| | - Katrinka M Kocha
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, Alberta Children's Hospital Research Institute, University of Calgary, 3330 Hospital Drive, Calgary, Alberta, T2N 4N1, Canada
| | - Emilio E Méndez-Olivos
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, Alberta Children's Hospital Research Institute, University of Calgary, 3330 Hospital Drive, Calgary, Alberta, T2N 4N1, Canada
| | - Tyler D Ruel
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, Alberta Children's Hospital Research Institute, University of Calgary, 3330 Hospital Drive, Calgary, Alberta, T2N 4N1, Canada
| | - Peng Huang
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, Alberta Children's Hospital Research Institute, University of Calgary, 3330 Hospital Drive, Calgary, Alberta, T2N 4N1, Canada.
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3
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Ferre-Fernández JJ, Muheisen S, Thompson S, Semina EV. CRISPR-Cas9-mediated functional dissection of the foxc1 genomic region in zebrafish identifies critical conserved cis-regulatory elements. Hum Genomics 2022; 16:49. [PMID: 36284357 PMCID: PMC9597995 DOI: 10.1186/s40246-022-00423-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 10/19/2022] [Indexed: 11/10/2022] Open
Abstract
FOXC1 encodes a forkhead-domain transcription factor associated with several ocular disorders. Correct FOXC1 dosage is critical to normal development, yet the mechanisms controlling its expression remain unknown. Together with FOXQ1 and FOXF2, FOXC1 is part of a cluster of FOX genes conserved in vertebrates. CRISPR-Cas9-mediated dissection of genomic sequences surrounding two zebrafish orthologs of FOXC1 was performed. This included five zebrafish-human conserved regions, three downstream of foxc1a and two remotely upstream of foxf2a/foxc1a or foxf2b/foxc1b clusters, as well as two intergenic regions between foxc1a/b and foxf2a/b lacking sequence conservation but positionally corresponding to the area encompassing a previously reported glaucoma-associated SNP in humans. Removal of downstream sequences altered foxc1a expression; moreover, zebrafish carrying deletions of two or three downstream elements demonstrated abnormal phenotypes including enlargement of the anterior chamber of the eye reminiscent of human congenital glaucoma. Deletions of distant upstream conserved elements influenced the expression of foxf2a/b or foxq1a/b but not foxc1a/b within each cluster. Removal of either intergenic sequence reduced foxc1a or foxc1b expression during late development, suggesting a role in transcriptional regulation despite the lack of conservation at the nucleotide level. Further studies of the identified regions in human patients may explain additional individuals with developmental ocular disorders.
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Affiliation(s)
- Jesús-José Ferre-Fernández
- Department of Pediatrics and Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI, 53226, USA
| | - Sanaa Muheisen
- Department of Pediatrics and Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI, 53226, USA
| | - Samuel Thompson
- Department of Pediatrics and Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI, 53226, USA
| | - Elena V Semina
- Department of Pediatrics and Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI, 53226, USA.
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, 53226, USA.
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, 53226, USA.
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4
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McGarvey AC, Kopp W, Vučićević D, Mattonet K, Kempfer R, Hirsekorn A, Bilić I, Gil M, Trinks A, Merks AM, Panáková D, Pombo A, Akalin A, Junker JP, Stainier DY, Garfield D, Ohler U, Lacadie SA. Single-cell-resolved dynamics of chromatin architecture delineate cell and regulatory states in zebrafish embryos. CELL GENOMICS 2022; 2:100083. [PMID: 36777038 PMCID: PMC9903790 DOI: 10.1016/j.xgen.2021.100083] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 09/24/2021] [Accepted: 12/10/2021] [Indexed: 11/16/2022]
Abstract
DNA accessibility of cis-regulatory elements (CREs) dictates transcriptional activity and drives cell differentiation during development. While many genes regulating embryonic development have been identified, the underlying CRE dynamics controlling their expression remain largely uncharacterized. To address this, we produced a multimodal resource and genomic regulatory map for the zebrafish community, which integrates single-cell combinatorial indexing assay for transposase-accessible chromatin with high-throughput sequencing (sci-ATAC-seq) with bulk histone PTMs and Hi-C data to achieve a genome-wide classification of the regulatory architecture determining transcriptional activity in the 24-h post-fertilization (hpf) embryo. We characterized the genome-wide chromatin architecture at bulk and single-cell resolution, applying sci-ATAC-seq on whole 24-hpf stage zebrafish embryos, generating accessibility profiles for ∼23,000 single nuclei. We developed a genome segmentation method, ScregSeg (single-cell regulatory landscape segmentation), for defining regulatory programs, and candidate CREs, specific to one or more cell types. We integrated the ScregSeg output with bulk measurements for histone post-translational modifications and 3D genome organization and identified new regulatory principles between chromatin modalities prevalent during zebrafish development. Sci-ATAC-seq profiling of npas4l/cloche mutant embryos identified novel cellular roles for this hematovascular transcriptional master regulator and suggests an intricate mechanism regulating its expression. Our work defines regulatory architecture and principles in the zebrafish embryo and establishes a resource of cell-type-specific genome-wide regulatory annotations and candidate CREs, providing a valuable open resource for genomics, developmental, molecular, and computational biology.
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Affiliation(s)
- Alison C. McGarvey
- Computational Regulatory Genomics, Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine, Berlin 10115, Germany,Quantitative Developmental Biology, Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin 10115, Germany
| | - Wolfgang Kopp
- Computational Regulatory Genomics, Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine, Berlin 10115, Germany,Bioinformatics and Omics Data Science Platform, Berlin Institute for Medical Systems Biology, Max Delbrück Centre for Molecular Medicine, Berlin 10115, Germany
| | - Dubravka Vučićević
- Computational Regulatory Genomics, Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine, Berlin 10115, Germany
| | - Kenny Mattonet
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim 61231, Germany
| | - Rieke Kempfer
- Epigenetic Regulation and Chromatin Architecture, Berlin Institute for Medical Systems Biology, Max Delbrück Centre for Molecular Medicine, Berlin, Germany,Institute for Biology, Humboldt Universität Berlin, Berlin 10115, Germany
| | - Antje Hirsekorn
- Computational Regulatory Genomics, Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine, Berlin 10115, Germany
| | - Ilija Bilić
- Computational Regulatory Genomics, Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine, Berlin 10115, Germany
| | - Marine Gil
- Computational Regulatory Genomics, Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine, Berlin 10115, Germany
| | - Alexandra Trinks
- IRI Life Sciences, Humboldt Universität Berlin, Berlin 10115, Germany
| | - Anne Margarete Merks
- Electrochemical Signaling in Development and Disease, Max Delbrück Centre for Molecular Medicine, Berlin, Germany,DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin 13125, Germany
| | - Daniela Panáková
- Electrochemical Signaling in Development and Disease, Max Delbrück Centre for Molecular Medicine, Berlin, Germany,DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin 13125, Germany
| | - Ana Pombo
- Epigenetic Regulation and Chromatin Architecture, Berlin Institute for Medical Systems Biology, Max Delbrück Centre for Molecular Medicine, Berlin, Germany,Institute for Biology, Humboldt Universität Berlin, Berlin 10115, Germany
| | - Altuna Akalin
- Bioinformatics and Omics Data Science Platform, Berlin Institute for Medical Systems Biology, Max Delbrück Centre for Molecular Medicine, Berlin 10115, Germany
| | - Jan Philipp Junker
- Quantitative Developmental Biology, Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin 10115, Germany
| | - Didier Y.R. Stainier
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim 61231, Germany
| | - David Garfield
- IRI Life Sciences, Humboldt Universität Berlin, Berlin 10115, Germany
| | - Uwe Ohler
- Computational Regulatory Genomics, Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine, Berlin 10115, Germany,Institute for Biology, Humboldt Universität Berlin, Berlin 10115, Germany,Corresponding author
| | - Scott Allen Lacadie
- Computational Regulatory Genomics, Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine, Berlin 10115, Germany,Berlin Institute of Health, Berlin 10178, Germany,Corresponding author
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5
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Zebrafish foxc1a controls ventricular chamber maturation by directly regulating wwtr1 and nkx2.5 expression. J Genet Genomics 2021; 49:559-568. [PMID: 34923164 DOI: 10.1016/j.jgg.2021.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 12/06/2021] [Accepted: 12/06/2021] [Indexed: 11/22/2022]
Abstract
Chamber maturation is a significant process in cardiac development. Disorders of this crucial process lead to a range of congenital heart defects. Foxc1a is a critical transcription factor reported to regulate the specification of cardiac progenitor cells. However, little is known about the role of Foxc1a in modulating chamber maturation. Previously, we reported that foxc1a-null zebrafish embryos exhibit disrupted heart structures and functions. In this study, we observed that ventricle structure and cardiomyocyte proliferation were abolished during chamber maturation in foxc1a-null zebrafish embryos. To observe the endogenous localization of Foxc1a in the hearts of living embryos, we inserted eyfp at the foxc1a genomic locus using TALEN. Analysis of the knockin zebrafish showed that foxc1a was widely expressed in ventricular cardiomyocytes during chamber development. Cardiac RNA sequencing analysis revealed downregulated expression of the Hippo signaling effector wwtr1. Dual-luciferase and chromatin immunoprecipitation assays revealed that Foxc1a could bind directly to three sites in the wwtr1 promoter region. Furthermore, wwtr1 mRNA overexpression was sufficient to reverse the ventricle defects during chamber maturation. Conditional overexpression of nkx2.5 also partially rescued the ventricular defects during chamber development. These findings demonstrate that wwtr1 and nkx2.5 are direct targets of Foxc1a during ventricular chamber maturation.
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6
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Shin M, Lawson ND. Back and forth: History of and new insights on the vertebrate lymphatic valve. Dev Growth Differ 2021; 63:523-535. [PMID: 34716915 PMCID: PMC9299638 DOI: 10.1111/dgd.12757] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 10/12/2021] [Accepted: 10/18/2021] [Indexed: 12/26/2022]
Abstract
Lymphatic valves develop from pre‐existing endothelial cells through a step‐wise process involving complex changes in cell shape and orientation, along with extracellular matrix interactions, to form two intraluminal leaflets. Once formed, valves prevent back‐flow within the lymphatic system to ensure drainage of interstitial fluid back into the circulatory system, thereby serving a critical role in maintaining fluid homeostasis. Despite the extensive anatomical characterization of lymphatic systems across numerous genus and species dating back several hundred years, valves were largely thought to be phylogenetically restricted to mammals. Accordingly, most insights into molecular and genetic mechanisms involved in lymphatic valve development have derived from mouse knockouts, as well as rare diseases in humans. However, we have recently used a combination of imaging and genetic analysis in the zebrafish to demonstrate that valves are a conserved feature of the teleost lymphatic system. Here, we provide a historical overview of comparative lymphatic valve anatomy together with recent efforts to define molecular pathways that contribute to lymphatic valve morphogenesis. Finally, we integrate our findings in zebrafish with previous work and highlight the benefits that this model provides for investigating lymphatic valve development.
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Affiliation(s)
- Masahiro Shin
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Nathan D Lawson
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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7
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French CR. Mechanistic Insights into Axenfeld-Rieger Syndrome from Zebrafish foxc1 and pitx2 Mutants. Int J Mol Sci 2021; 22:ijms221810001. [PMID: 34576164 PMCID: PMC8472202 DOI: 10.3390/ijms221810001] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 09/03/2021] [Accepted: 09/05/2021] [Indexed: 12/11/2022] Open
Abstract
Axenfeld-Rieger syndrome (ARS) encompasses a group of developmental disorders that affect the anterior segment of the eye, as well as systemic developmental defects in some patients. Malformation of the ocular anterior segment often leads to secondary glaucoma, while some patients also present with cardiovascular malformations, craniofacial and dental abnormalities and additional periumbilical skin. Genes that encode two transcription factors, FOXC1 and PITX2, account for almost half of known cases, while the genetic lesions in the remaining cases remain unresolved. Given the genetic similarity between zebrafish and humans, as well as robust antisense inhibition and gene editing technologies available for use in these animals, loss of function zebrafish models for ARS have been created and shed light on the mechanism(s) whereby mutations in these two transcription factors cause such a wide array of developmental phenotypes. This review summarizes the published phenotypes in zebrafish foxc1 and pitx2 loss of function models and discusses possible mechanisms that may be used to target pharmaceutical development and therapeutic interventions.
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Affiliation(s)
- Curtis R French
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland and Labrador, St. John's, NL A1B 3V6, Canada
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8
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Ferre-Fernández JJ, Sorokina EA, Thompson S, Collery RF, Nordquist E, Lincoln J, Semina EV. Disruption of foxc1 genes in zebrafish results in dosage-dependent phenotypes overlapping Axenfeld-Rieger syndrome. Hum Mol Genet 2021; 29:2723-2735. [PMID: 32720677 DOI: 10.1093/hmg/ddaa163] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/16/2020] [Accepted: 07/21/2020] [Indexed: 12/14/2022] Open
Abstract
The Forkhead Box C1 (FOXC1) gene encodes a forkhead/winged helix transcription factor involved in embryonic development. Mutations in this gene cause dysgenesis of the anterior segment of the eye, most commonly Axenfeld-Rieger syndrome (ARS), often with other systemic features. The developmental mechanisms and pathways regulated by FOXC1 remain largely unknown. There are two conserved orthologs of FOXC1 in zebrafish, foxc1a and foxc1b. To further examine the role of FOXC1 in vertebrates, we generated foxc1a and foxc1b single knockout zebrafish lines and bred them to obtain various allelic combinations. Three genotypes demonstrated visible phenotypes: foxc1a-/- single homozygous and foxc1-/- double knockout homozygous embryos presented with similar characteristics comprised of severe global vascular defects and early lethality, as well as microphthalmia, periocular edema and absence of the anterior chamber of the eye; additionally, fish with heterozygous loss of foxc1a combined with homozygosity for foxc1b (foxc1a+/-;foxc1b-/-) demonstrated craniofacial defects, heart anomalies and scoliosis. All other single and combined genotypes appeared normal. Analysis of foxc1 expression detected a significant increase in foxc1a levels in homozygous and heterozygous mutant eyes, suggesting a mechanism for foxc1a upregulation when its function is compromised; interestingly, the expression of another ARS-associated gene, pitx2, was responsive to the estimated level of wild-type Foxc1a, indicating a possible role for this protein in the regulation of pitx2 expression. Altogether, our results support a conserved role for foxc1 in the formation of many organs, consistent with the features observed in human patients, and highlight the importance of correct FOXC1/foxc1 dosage for vertebrate development.
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Affiliation(s)
- Jesús-José Ferre-Fernández
- Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Elena A Sorokina
- Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Samuel Thompson
- Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Ross F Collery
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Emily Nordquist
- Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Joy Lincoln
- Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA.,Division of Pediatric Cardiology, Herma Heart Institute, Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Elena V Semina
- Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA.,Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI 53226, USA.,Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
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9
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The Axenfeld-Rieger Syndrome Gene FOXC1 Contributes to Left-Right Patterning. Genes (Basel) 2021; 12:genes12020170. [PMID: 33530637 PMCID: PMC7912076 DOI: 10.3390/genes12020170] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/14/2021] [Accepted: 01/21/2021] [Indexed: 02/06/2023] Open
Abstract
Precise spatiotemporal expression of the Nodal-Lefty-Pitx2 cascade in the lateral plate mesoderm establishes the left–right axis, which provides vital cues for correct organ formation and function. Mutations of one cascade constituent PITX2 and, separately, the Forkhead transcription factor FOXC1 independently cause a multi-system disorder known as Axenfeld–Rieger syndrome (ARS). Since cardiac involvement is an established ARS phenotype and because disrupted left–right patterning can cause congenital heart defects, we investigated in zebrafish whether foxc1 contributes to organ laterality or situs. We demonstrate that CRISPR/Cas9-generated foxc1a and foxc1b mutants exhibit abnormal cardiac looping and that the prevalence of cardiac situs defects is increased in foxc1a−/−; foxc1b−/− homozygotes. Similarly, double homozygotes exhibit isomerism of the liver and pancreas, which are key features of abnormal gut situs. Placement of the asymmetric visceral organs relative to the midline was also perturbed by mRNA overexpression of foxc1a and foxc1b. In addition, an analysis of the left–right patterning components, identified in the lateral plate mesoderm of foxc1 mutants, reduced or abolished the expression of the NODAL antagonist lefty2. Together, these data reveal a novel contribution from foxc1 to left–right patterning, demonstrating that this role is sensitive to foxc1 gene dosage, and provide a plausible mechanism for the incidence of congenital heart defects in Axenfeld–Rieger syndrome patients.
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10
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Hung IC, Chen TM, Lin JP, Tai YL, Shen TL, Lee SJ. Wnt5b integrates Fak1a to mediate gastrulation cell movements via Rac1 and Cdc42. Open Biol 2020; 10:190273. [PMID: 32097584 PMCID: PMC7058935 DOI: 10.1098/rsob.190273] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Focal adhesion kinase (FAK) mediates vital cellular pathways during development. Despite its necessity, how FAK regulates and integrates with other signals during early embryogenesis remains poorly understood. We found that the loss of Fak1a impaired epiboly, convergent extension and hypoblast cell migration in zebrafish embryos. We also observed a clear disturbance in cortical actin at the blastoderm margin and distribution of yolk syncytial nuclei. In addition, we investigated a possible link between Fak1a and a well-known gastrulation regulator, Wnt5b, and revealed that the overexpression of fak1a or wnt5b could cross-rescue convergence defects induced by a wnt5b or fak1a antisense morpholino (MO), respectively. Wnt5b and Fak1a were shown to converge in regulating Rac1 and Cdc42, which could synergistically rescue wnt5b and fak1a morphant phenotypes. Furthermore, we generated several alleles of fak1a mutants using CRISPR/Cas9, but those mutants only revealed mild gastrulation defects. However, injection of a subthreshold level of the wnt5b MO induced severe gastrulation defects in fak1a mutants, which suggested that the upregulated expression of wnt5b might complement the loss of Fak1a. Collectively, we demonstrated that a functional interaction between Wnt and FAK signalling mediates gastrulation cell movements via the possible regulation of Rac1 and Cdc42 and subsequent actin dynamics.
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Affiliation(s)
- I-Chen Hung
- Department of Life Science, National Taiwan University, No. 1, Roosevelt Road, Section 4, Taipei 10617, Taiwan
| | - Tsung-Ming Chen
- Department of Life Science, National Taiwan University, No. 1, Roosevelt Road, Section 4, Taipei 10617, Taiwan.,Department of Plant Pathology and Microbiology, National Taiwan University, No. 1, Roosevelt Road, Section 4, Taipei 10617, Taiwan.,Department and Graduate Institute of Aquaculture, National Kaohsiung Marine University, Kaohsiung, Taiwan
| | - Jing-Ping Lin
- Department of Plant Pathology and Microbiology, National Taiwan University, No. 1, Roosevelt Road, Section 4, Taipei 10617, Taiwan
| | - Yu-Ling Tai
- Department of Plant Pathology and Microbiology, National Taiwan University, No. 1, Roosevelt Road, Section 4, Taipei 10617, Taiwan
| | - Tang-Long Shen
- Department of Plant Pathology and Microbiology, National Taiwan University, No. 1, Roosevelt Road, Section 4, Taipei 10617, Taiwan.,Center for Biotechnology, National Taiwan University, Taipei, Taiwan
| | - Shyh-Jye Lee
- Department of Life Science, National Taiwan University, No. 1, Roosevelt Road, Section 4, Taipei 10617, Taiwan.,Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan.,Center for Biotechnology, National Taiwan University, Taipei, Taiwan.,Center for Systems Biology, National Taiwan University, Taipei, Taiwan
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11
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Wang H, Holland PWH, Takahashi T. Gene profiling of head mesoderm in early zebrafish development: insights into the evolution of cranial mesoderm. EvoDevo 2019; 10:14. [PMID: 31312422 PMCID: PMC6612195 DOI: 10.1186/s13227-019-0128-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 06/26/2019] [Indexed: 11/10/2022] Open
Abstract
Background The evolution of the head was one of the key events that marked the transition from invertebrates to vertebrates. With the emergence of structures such as eyes and jaws, vertebrates evolved an active and predatory life style and radiated into diversity of large-bodied animals. These organs are moved by cranial muscles that derive embryologically from head mesoderm. Compared with other embryonic components of the head, such as placodes and cranial neural crest cells, our understanding of cranial mesoderm is limited and is restricted to few species. Results Here, we report the expression patterns of key genes in zebrafish head mesoderm at very early developmental stages. Apart from a basic anterior–posterior axis marked by a combination of pitx2 and tbx1 expression, we find that most gene expression patterns are poorly conserved between zebrafish and chick, suggesting fewer developmental constraints imposed than in trunk mesoderm. Interestingly, the gene expression patterns clearly show the early establishment of medial–lateral compartmentalisation in zebrafish head mesoderm, comprising a wide medial zone flanked by two narrower strips. Conclusions In zebrafish head mesoderm, there is no clear molecular regionalisation along the anteroposterior axis as previously reported in chick embryos. In contrast, the medial–lateral regionalisation is formed at early developmental stages. These patterns correspond to the distinction between paraxial mesoderm and lateral plate mesoderm in the trunk, suggesting a common groundplan for patterning head and trunk mesoderm. By comparison of these expression patterns to that of amphioxus homologues, we argue for an evolutionary link between zebrafish head mesoderm and amphioxus anteriormost somites. Electronic supplementary material The online version of this article (10.1186/s13227-019-0128-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Huijia Wang
- 1Faculty of Biology, Medicine and Health, The University of Manchester, Oxford Road, Manchester, M13 9PT UK
| | - Peter W H Holland
- 2Department of Zoology, University of Oxford, Zoology Research and Administration Building, 11a Mansfield Road, Oxford, OX1 3SZ UK
| | - Tokiharu Takahashi
- 1Faculty of Biology, Medicine and Health, The University of Manchester, Oxford Road, Manchester, M13 9PT UK
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12
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Whitesell TR, Chrystal PW, Ryu JR, Munsie N, Grosse A, French CR, Workentine ML, Li R, Zhu LJ, Waskiewicz A, Lehmann OJ, Lawson ND, Childs SJ. foxc1 is required for embryonic head vascular smooth muscle differentiation in zebrafish. Dev Biol 2019; 453:34-47. [PMID: 31199900 DOI: 10.1016/j.ydbio.2019.06.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/29/2019] [Accepted: 06/09/2019] [Indexed: 11/15/2022]
Abstract
Vascular smooth muscle of the head derives from neural crest, but developmental mechanisms and early transcriptional drivers of the vSMC lineage are not well characterized. We find that in early development, the transcription factor foxc1b is expressed in mesenchymal cells that associate with the vascular endothelium. Using timelapse imaging, we observe that foxc1b expressing mesenchymal cells differentiate into acta2 expressing vascular mural cells. We show that in zebrafish, while foxc1b is co-expressed in acta2 positive smooth muscle cells that associate with large diameter vessels, it is not co-expressed in capillaries where pdgfrβ positive pericytes are located. In addition to being an early marker of the lineage, foxc1 is essential for vSMC differentiation; we find that foxc1 loss of function mutants have defective vSMC differentiation and that early genetic ablation of foxc1b or acta2 expressing populations blocks vSMC differentiation. Furthermore, foxc1 is expressed upstream of acta2 and is required for acta2 expression in vSMCs. Using RNA-Seq we determine an enriched intersectional gene expression profile using dual expression of foxc1b and acta2 to identify novel vSMC markers. Taken together, our data suggests that foxc1 is a marker of vSMCs and plays a critical functional role in promoting their differentiation.
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Affiliation(s)
- Thomas R Whitesell
- Alberta Children's Hospital Research Institute, University of Calgary, Canada; Department of Biochemistry and Molecular Biology, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, Canada, T2N 4N1
| | - Paul W Chrystal
- Departments of Ophthalmology, and Medical Genetics, University of Alberta, Edmonton, Alberta, Canada; Department of Biological Sciences, CW405, Biological Sciences Bldg., 11455, Saskatchewan Dr., University of Alberta, Edmonton, AB, T6G 2E9, Canada; Women & Children's Health Research Institute, ECHA 4-081, 11405 87, Ave NW, University of Alberta, Edmonton, AB, T6G 1C9, Canada; Neurosciences and Mental Health Institute, 4-120 Katz Group Centre, University of Alberta, Edmonton, AB, T6G 2E1, Canada
| | - Jae-Ryeon Ryu
- Alberta Children's Hospital Research Institute, University of Calgary, Canada; Department of Biochemistry and Molecular Biology, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, Canada, T2N 4N1
| | - Nicole Munsie
- Alberta Children's Hospital Research Institute, University of Calgary, Canada; Department of Biochemistry and Molecular Biology, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, Canada, T2N 4N1
| | - Ann Grosse
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA, USA, 01605
| | - Curtis R French
- Department of Biological Sciences, CW405, Biological Sciences Bldg., 11455, Saskatchewan Dr., University of Alberta, Edmonton, AB, T6G 2E9, Canada; Women & Children's Health Research Institute, ECHA 4-081, 11405 87, Ave NW, University of Alberta, Edmonton, AB, T6G 1C9, Canada; Neurosciences and Mental Health Institute, 4-120 Katz Group Centre, University of Alberta, Edmonton, AB, T6G 2E1, Canada
| | - Matthew L Workentine
- Faculty of Veterinary Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, Canada, T2N 4N1
| | - Rui Li
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA, USA, 01605
| | - Lihua Julie Zhu
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA, USA, 01605; Program in Bioinformatics and Integrative Biology, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA, 01605
| | - Andrew Waskiewicz
- Department of Biological Sciences, CW405, Biological Sciences Bldg., 11455, Saskatchewan Dr., University of Alberta, Edmonton, AB, T6G 2E9, Canada; Women & Children's Health Research Institute, ECHA 4-081, 11405 87, Ave NW, University of Alberta, Edmonton, AB, T6G 1C9, Canada; Neurosciences and Mental Health Institute, 4-120 Katz Group Centre, University of Alberta, Edmonton, AB, T6G 2E1, Canada
| | - Ordan J Lehmann
- Departments of Ophthalmology, and Medical Genetics, University of Alberta, Edmonton, Alberta, Canada
| | - Nathan D Lawson
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA, USA, 01605
| | - Sarah J Childs
- Alberta Children's Hospital Research Institute, University of Calgary, Canada; Department of Biochemistry and Molecular Biology, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, Canada, T2N 4N1.
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13
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Li J, Yue Y, Dong X, Jia W, Li K, Liang D, Dong Z, Wang X, Nan X, Zhang Q, Zhao Q. Zebrafish foxc1a plays a crucial role in early somitogenesis by restricting the expression of aldh1a2 directly. J Biol Chem 2015; 290:10216-28. [PMID: 25724646 DOI: 10.1074/jbc.m114.612572] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Indexed: 11/06/2022] Open
Abstract
Foxc1a is a member of the forkhead transcription factors. It plays an essential role in zebrafish somitogenesis. However, little is known about the molecular mechanisms underlying its controlling somitogenesis. To uncover how foxc1a regulates zebrafish somitogenesis, we generated foxc1a knock-out zebrafish using TALEN (transcription activator-like effector nuclease) technology. The foxc1a null embryos exhibited defective somites at early development. Analyses on the expressions of the key genes that control processes of somitogenesis revealed that foxc1a controlled early somitogenesis by regulating the expression of myod1. In the somites of foxc1a knock-out embryos, expressions of fgf8a and deltaC were abolished, whereas the expression of aldh1a2 (responsible for providing retinoic acid signaling) was significantly increased. Once the increased retinoic acid level in the foxc1a null embryos was reduced by knocking down aldh1a2, the reduced expression of myod1 was partially rescued by resuming expressions of fgf8a and deltaC in the somites of the mutant embryos. Moreover, a chromatin immunoprecipitation assay on zebrafish embryos revealed that Foxc1a bound aldh1a2 promoter directly. On the other hand, neither knocking down fgf8a nor inhibiting Notch signaling affected the expression of aldh1a2, although knocking down fgf8a reduced expression of deltaC in the somites of zebrafish embryos at early somitogenesis and vice versa. Taken together, our results demonstrate that foxc1a plays an essential role in early somitogenesis by controlling Fgf and Notch signaling through restricting the expression of aldh1a2 in paraxial mesoderm directly.
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Affiliation(s)
- Jingyun Li
- From the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing 210061, China and the Maternal and Child Health Medical Institute, Nanjing Maternal and Child Health Care Hospital Affiliated with Nanjing Medical University, Nanjing 210004, China
| | - Yunyun Yue
- From the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing 210061, China and
| | - Xiaohua Dong
- From the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing 210061, China and
| | - Wenshuang Jia
- From the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing 210061, China and
| | - Kui Li
- From the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing 210061, China and
| | - Dong Liang
- From the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing 210061, China and
| | - Zhangji Dong
- From the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing 210061, China and
| | - Xiaoxiao Wang
- From the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing 210061, China and
| | - Xiaoxi Nan
- From the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing 210061, China and
| | - Qinxin Zhang
- From the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing 210061, China and
| | - Qingshun Zhao
- From the MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing 210061, China and
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14
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Kroeger PT, Wingert RA. Using zebrafish to study podocyte genesis during kidney development and regeneration. Genesis 2014; 52:771-92. [PMID: 24920186 DOI: 10.1002/dvg.22798] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 06/08/2014] [Accepted: 06/09/2014] [Indexed: 12/21/2022]
Abstract
During development, vertebrates form a progression of up to three different kidneys that are comprised of functional units termed nephrons. Nephron composition is highly conserved across species, and an increasing appreciation of the similarities between zebrafish and mammalian nephron cell types has positioned the zebrafish as a relevant genetic system for nephrogenesis studies. A key component of the nephron blood filter is a specialized epithelial cell known as the podocyte. Podocyte research is of the utmost importance as a vast majority of renal diseases initiate with the dysfunction or loss of podocytes, resulting in a condition known as proteinuria that causes nephron degeneration and eventually leads to kidney failure. Understanding how podocytes develop during organogenesis may elucidate new ways to promote nephron health by stimulating podocyte replacement in kidney disease patients. In this review, we discuss how the zebrafish model can be used to study kidney development, and how zebrafish research has provided new insights into podocyte lineage specification and differentiation. Further, we discuss the recent discovery of podocyte regeneration in adult zebrafish, and explore how continued basic research using zebrafish can provide important knowledge about podocyte genesis in embryonic and adult environments. genesis 52:771-792, 2014. © 2014 Wiley Periodicals, Inc.
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Affiliation(s)
- Paul T Kroeger
- Department of Biological Sciences and Center for Zebrafish Research, University of Notre Dame, Notre Dame, Indiana, 46556
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15
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Gerlach GF, Wingert RA. Kidney organogenesis in the zebrafish: insights into vertebrate nephrogenesis and regeneration. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2012; 2:559-85. [PMID: 24014448 DOI: 10.1002/wdev.92] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Vertebrates form a progressive series of up to three kidney organs during development-the pronephros, mesonephros, and metanephros. Each kidney derives from the intermediate mesoderm and is comprised of conserved excretory units called nephrons. The zebrafish is a powerful model for vertebrate developmental genetics, and recent studies have illustrated that zebrafish and mammals share numerous similarities in nephron composition and physiology. The zebrafish embryo forms an architecturally simple pronephros that has two nephrons, and these eventually become a scaffold onto which a mesonephros of several hundred nephrons is constructed during larval stages. In adult zebrafish, the mesonephros exhibits ongoing nephrogenesis, generating new nephrons from a local pool of renal progenitors during periods of growth or following kidney injury. The characteristics of the zebrafish pronephros and mesonephros make them genetically tractable kidney systems in which to study the functions of renal genes and address outstanding questions about the mechanisms of nephrogenesis. Here, we provide an overview of the formation and composition of these zebrafish kidney organs, and discuss how various zebrafish mutants, gene knockdowns, and transgenic models have created frameworks in which to further delineate nephrogenesis pathways.
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Affiliation(s)
- Gary F Gerlach
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
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16
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Abstract
The pathophysiology of congenital and neonatal hydrocephalus is not well understood although the prognosis for patients with this disorder is far from optimal. A major obstacle to advancing our knowledge of the causes of this disorder and the cellular responses that accompany it is the multifactorial nature of hydrocephalus. Not only is the epidemiology varied and complex, but the injury mechanisms are numerous and overlapping. Nevertheless, several conclusions can be made with certainty: the age of onset strongly influences the degree of impairment; injury severity is dependent on the magnitude and duration of ventriculomegaly; the primary targets are periventricular axons, myelin, and microvessels; cerebrovascular injury mechanisms are prominent; gliosis and neuroinflammation play major roles; some but not all changes are preventable by draining cerebrospinal fluid with shunts and third ventriculostomies; cellular plasticity and physiological compensation probably occur but this is a major under-studied area; and pharmacologic interventions are promising. Rat and mouse models have provided important insights into the pathogenesis of congenital and neonatal hydrocephalus. Ependymal denudation of the ventricular lining appears to affect the development of neural progenitors exposed to cerebrospinal fluid, and alterations of the subcommissural organ influence the patency of the cerebral aqueduct. Recently these impairments have been observed in patients with fetal-onset hydrocephalus, so experimental findings are beginning to be corroborated in humans. These correlations, coupled with advanced genetic manipulations in animals and successful pharmacologic interventions, support the view that improved treatments for congenital and neonatal hydrocephalus are on the horizon.
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Affiliation(s)
- James P McAllister
- Department of Neurosurgery, Division of Pediatric Neurosurgery, University of Utah and Primary Children's Medical Center, Salt Lake City, UT 84132, USA.
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17
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Abstract
RATIONALE Endothelial cells are developmentally derived from angioblasts specified in the mesodermal germ cell layer. The transcription factor etsrp/etv2 is at the top of the known genetic hierarchy for angioblast development. The transcriptional events that induce etsrp expression and angioblast specification are not well understood. OBJECTIVE We generated etsrp:gfp transgenic zebrafish and used them to identify regulatory regions and transcription factors critical for etsrp expression and angioblast specification from mesoderm. METHODS AND RESULTS To investigate the mechanisms that initiate angioblast cell transcription during embryogenesis, we have performed promoter analysis of the etsrp locus in zebrafish. We describe three enhancer elements sufficient for endothelial gene expression when place in front of a heterologous promoter. The deletion of all 3 regulatory regions led to a near complete loss of endothelial expression from the etsrp promoter. One of the enhancers, located 2.3 kb upstream of etsrp contains a consensus FOX binding site that binds Foxc1a and Foxc1b in vitro by EMSA and in vivo using ChIP. Combined knockdown of foxc1a/b, using morpholinos, led to a significant decrease in etsrp expression at early developmental stages as measured by quantitative reverse transcriptase-polymerase chain reaction and in situ hybridization. Decreased expression of primitive erythrocyte genes scl and gata1 was also observed, whereas pronephric gene pax2a was relatively normal in expression level and pattern. CONCLUSIONS These findings identify mesodermal foxc1a/b as a direct upstream regulator of etsrp in angioblasts. This establishes a new molecular link in the process of mesoderm specification into angioblast.
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Affiliation(s)
- Matthew B Veldman
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, 621 Charles E Young Dr South, Los Angeles, CA 90095-1606, USA
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18
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Wotton KR, Shimeld SM. Analysis of lamprey clustered Fox genes: insight into Fox gene evolution and expression in vertebrates. Gene 2011; 489:30-40. [PMID: 21907770 DOI: 10.1016/j.gene.2011.08.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2011] [Revised: 08/02/2011] [Accepted: 08/18/2011] [Indexed: 10/17/2022]
Abstract
In the human genome, members of the FoxC, FoxF, FoxL1, and FoxQ1 gene families are found in two paralagous clusters. One cluster contains the genes FOXQ1, FOXF2, FOXC1 and the second consists of FOXF1, FOXC2, and FOXL1. In jawed vertebrates these genes are known to be expressed in different pharyngeal tissues and all, except FoxQ1, are involved in patterning the early embryonic mesoderm. We have previously traced the evolution of this cluster in the bony vertebrates, and the gene content is identical in the dogfish, a member of the most basally branching lineage of the jawed vertebrates. Here we extend these analyses to jawless vertebrates. Using genomic searches and molecular approaches we have identified homologues of these genes from lampreys. We identify two FoxC genes, two FoxF genes, two FoxQ1 genes and single FoxL1 gene. We examine the embryonic expression of one predominantly mesodermally expressed gene family, FoxC, and the endodermally expressed member of the cluster, FoxQ1. We identified FoxQ1 transcripts in the pharyngeal endoderm, while the two FoxC genes are differentially expressed in the pharyngeal mesenchyme and ectoderm. Furthermore we identify conserved expression of lamprey FoxC genes in the paraxial and intermediate mesoderms. We interpret our results through a chordate-wide comparison of expression patterns and discuss gene content in the context of theories on the evolution of the vertebrate genome.
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Affiliation(s)
- Karl R Wotton
- Department of Zoology, University of Oxford, The Tinbergen Building, South Parks Road, Oxford, OX1 3PS, UK.
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19
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O'Brien LL, Grimaldi M, Kostun Z, Wingert RA, Selleck R, Davidson AJ. Wt1a, Foxc1a, and the Notch mediator Rbpj physically interact and regulate the formation of podocytes in zebrafish. Dev Biol 2011; 358:318-30. [PMID: 21871448 DOI: 10.1016/j.ydbio.2011.08.005] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2010] [Revised: 08/05/2011] [Accepted: 08/08/2011] [Indexed: 01/02/2023]
Abstract
Podocytes help form the glomerular blood filtration barrier in the kidney and their injury or loss leads to renal disease. The Wilms' tumor suppressor-1 (Wt1) and the FoxC1/2 transcription factors, as well as Notch signaling, have been implicated as important regulators of podocyte fate. It is not known whether these factors work in parallel or sequentially on different gene targets, or as higher-order transcriptional complexes on common genes. Here, we use the zebrafish to demonstrate that embryos treated with morpholinos against wt1a, foxc1a, or the Notch transcriptional mediator rbpj develop fewer podocytes, as determined by wt1b, hey1 and nephrin expression, while embryos deficient in any two of these factors completely lack podocytes. From GST-pull-downs and co-immunoprecipitation experiments we show that Wt1a, Foxc1a, and Rbpj can physically interact with each other, whereas only Rbpj binds to the Notch intracellular domain (NICD). In transactivation assays, combinations of Wt1, FoxC1/2, and NICD synergistically induce the Hey1 promoter, and have additive or repressive effects on the Podocalyxin promoter, depending on dosage. Taken together, these data suggest that Wt1, FoxC1/2, and Notch signaling converge on common target genes where they physically interact to regulate a podocyte-specific gene program. These findings further our understanding of the transcriptional circuitry responsible for podocyte formation and differentiation during kidney development.
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Affiliation(s)
- Lori L O'Brien
- Center for Regenerative Medicine and Department of Medicine, Massachusetts General Hospital, Harvard Medical School and Harvard Stem Cell Institute, Boston, MA 02114, USA
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20
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Zhang G. An evo-devo view on the origin of the backbone: evolutionary development of the vertebrae. Integr Comp Biol 2009; 49:178-86. [PMID: 21669856 DOI: 10.1093/icb/icp061] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Vertebral columns are a group of diverse axial structures that define the vertebrates and provide supportive, locomotive, protective, and other important functions. The embryonic origin of the first vertebral element in this subphylum, the lamprey arcualia, has remained a puzzle for more than a century although much developmental and genetic progress has been made. The comparative approach is a very powerful tool for studying vertebrate morphological variation and understanding how the novel structures were generated during evolution. Here, I first briefly describe the vertebral structures and their developmental processes in major taxa, and then analyze the most recently published data on the basal vertebrates. Finally, an ontogenetic and phylogenetic origin is proposed. The lamprey may have already evolved a sclerotome, which gave rise to arcualia ontogenetically; whole genome duplications likely promoted the establishment of sclerotomal core genetic program by gene co-options.
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Affiliation(s)
- Guangjun Zhang
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, E17-336, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
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21
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Skarie JM, Link BA. FoxC1 is essential for vascular basement membrane integrity and hyaloid vessel morphogenesis. Invest Ophthalmol Vis Sci 2009; 50:5026-34. [PMID: 19458328 DOI: 10.1167/iovs.09-3447] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
PURPOSE Alterations in FOXC1 dosage lead to a spectrum of highly penetrant, ocular anterior segment dysgenesis phenotypes. The most serious outcome is the development of glaucoma, which occurs in 50% to 75% of patients. Therefore, the need to identify specific pathways and genes that interact with FOXC1 to promote glaucoma is great. In this study, the authors investigated the loss of foxC1 in the zebrafish to characterize phenotypes and gene interactions that may impact glaucoma pathogenesis. METHODS Morpholino knockdown in zebrafish, RNA and protein marker analyses, transgenic reporter lines, and angiography, along with histology and transmission electron microscopy, were used to study foxC1 function and gene interactions. RESULTS Zebrafish foxC1 genes were expressed dynamically in the developing vasculature and periocular mesenchyme during development. Multiple ocular and vascular defects were found after the knockdown of foxC1. Defects in the hyaloid vasculature, arteriovenous malformations, and coarctation of the aorta were observed with maximal depletion of foxC1. Partial loss of foxC1 resulted in CNS and ocular hemorrhages, defects in intersegmental vessel patterning, and increased vascular permeability. To investigate the basis for these disruptions, the ultrastructure of foxC1-depleted hyaloid vascular cells was studied. These experiments, along with laminin-111 immunoreactivity, revealed disruptions in basement membrane integrity. Finally, codepletion of laminin alpha-1 and foxC1 uncovered a genetic interaction between these genes during development. CONCLUSIONS Genetic interactions between FOXC1 and basement membrane components influence vascular stability and may impact glaucoma development and increase stroke risk in FOXC1 patients.
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Affiliation(s)
- Jonathan M Skarie
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
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Ogura E, Okuda Y, Kondoh H, Kamachi Y. Adaptation of GAL4 activators for GAL4 enhancer trapping in zebrafish. Dev Dyn 2009; 238:641-55. [PMID: 19191223 DOI: 10.1002/dvdy.21863] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
An enhancer trap-based GAL4-UAS system in zebrafish requires strong GAL4 activators with minimal adverse effects. However, the activity of yeast GAL4 is too low in zebrafish, while a fusion protein of the GAL4 DNA-binding domain and the VP16 activation domain is toxic to embryonic development, even when expressed at low levels. To alleviate this toxicity, we developed variant GAL4 activators by fusing either multimeric forms of the VP16 minimal activation domain or the NF-kappaB activation domain to the GAL4 DNA-binding domain. These variant GAL4 activators are sufficiently innocuous and yet highly effective transactivators in developing zebrafish. Enhancer-trap vectors containing these GAL4 activators downstream of an appropriate weak promoter were randomly inserted into the zebrafish genome using the Sleeping Beauty transposon system. By the combination of these genetic elements, we have successfully developed enhancer trap lines that activate UAS-dependent reporter genes in a tissue-specific fashion that reflects trapped enhancer activities.
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Affiliation(s)
- Eri Ogura
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
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Chong SW, Korzh V, Jiang YJ. Myogenesis and molecules - insights from zebrafish Danio rerio. JOURNAL OF FISH BIOLOGY 2009; 74:1693-1755. [PMID: 20735668 DOI: 10.1111/j.1095-8649.2009.02174.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Myogenesis is a fundamental process governing the formation of muscle in multicellular organisms. Recent studies in zebrafish Danio rerio have described the molecular events occurring during embryonic morphogenesis and have thus greatly clarified this process, helping to distinguish between the events that give rise to fast v. slow muscle. Coupled with the well-known Hedgehog signalling cascade and a wide variety of cellular processes during early development, the continual research on D. rerio slow muscle precursors has provided novel insights into their cellular behaviours in this organism. Similarly, analyses on fast muscle precursors have provided knowledge of the behaviour of a sub-set of epitheloid cells residing in the anterior domain of somites. Additionally, the findings by various groups on the roles of several molecules in somitic myogenesis have been clarified in the past year. In this study, the authors briefly review the current trends in the field of research of D. rerio trunk myogenesis.
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Affiliation(s)
- S-W Chong
- Laboratory of Developmental Signalling and Patterning, Genes and Development Division, A STAR (Agency for Science, Technology and Research), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore.
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The Cooperative Roles of Foxc1 and Foxc2 in Cardiovascular Development. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 665:63-77. [DOI: 10.1007/978-1-4419-1599-3_5] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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25
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De Val S, Chi NC, Meadows SM, Minovitsky S, Anderson JP, Harris IS, Ehlers ML, Agarwal P, Visel A, Xu SM, Pennacchio LA, Dubchak I, Krieg PA, Stainier DYR, Black BL. Combinatorial regulation of endothelial gene expression by ets and forkhead transcription factors. Cell 2008; 135:1053-64. [PMID: 19070576 DOI: 10.1016/j.cell.2008.10.049] [Citation(s) in RCA: 257] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Revised: 08/20/2008] [Accepted: 10/20/2008] [Indexed: 11/30/2022]
Abstract
Vascular development begins when mesodermal cells differentiate into endothelial cells, which then form primitive vessels. It has been hypothesized that endothelial-specific gene expression may be regulated combinatorially, but the transcriptional mechanisms governing specificity in vascular gene expression remain incompletely understood. Here, we identify a 44 bp transcriptional enhancer that is sufficient to direct expression specifically and exclusively to the developing vascular endothelium. This enhancer is regulated by a composite cis-acting element, the FOX:ETS motif, which is bound and synergistically activated by Forkhead and Ets transcription factors. We demonstrate that coexpression of the Forkhead protein FoxC2 and the Ets protein Etv2 induces ectopic expression of vascular genes in Xenopus embryos, and that combinatorial knockdown of the orthologous genes in zebrafish embryos disrupts vascular development. Finally, we show that FOX:ETS motifs are present in many known endothelial-specific enhancers and that this motif is an efficient predictor of endothelial enhancers in the human genome.
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Affiliation(s)
- Sarah De Val
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94158-2517, USA
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Wotton KR, Mazet F, Shimeld SM. Expression of FoxC, FoxF, FoxL1, and FoxQ1 genes in the dogfish Scyliorhinus canicula defines ancient and derived roles for Fox genes in vertebrate development. Dev Dyn 2008; 237:1590-603. [PMID: 18498098 DOI: 10.1002/dvdy.21553] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
In the human genome, members of the FoxC, FoxF, FoxL1, and FoxQ1 gene families are found in two paralagous clusters. Here we characterize all four gene families in the dogfish Scyliorhinus canicula, a member of the cartilaginous fish lineage that diverged before the radiation of osteichthyan vertebrates. We identify two FoxC genes, two FoxF genes, and single FoxQ1 and FoxL1 genes, demonstrating cluster duplication preceded the radiation of gnathostomes. The expression of all six genes was analyzed by in situ hybridization. The results show conserved expression of FoxL1, FoxF, and FoxC genes in different compartments of the mesoderm and of FoxQ1 in pharyngeal endoderm and its derivatives, confirming these as ancient sites of Fox gene expression, and also illustrate multiple cases of lineage-specific expression domains. Comparison to invertebrate chordates shows that the majority of conserved vertebrate expression domains mark tissues that are part of the primitive chordate body plan.
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Affiliation(s)
- Karl R Wotton
- Department of Zoology, University of Oxford, The Tinbergen Building, South Parks Road, Oxford, United Kingdom
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27
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Abstract
Somites are the most obvious metameric structures in the vertebrate embryo. They are mesodermal segments that form in bilateral pairs flanking the notochord and are created sequentially in an anterior to posterior sequence concomitant with the posterior growth of the trunk and tail. Zebrafish somitogenesis is regulated by a clock that causes cells in the presomitic mesoderm (PSM) to undergo cyclical activation and repression of several notch pathway genes. Coordinated oscillation among neighboring cells manifests as stripes of gene expression that pass through the cells of the PSM in a posterior to anterior direction. As axial growth continually adds new cells to the posterior tail bud, cells of the PSM become relatively less posterior. This gradual assumption of a more anterior position occurs over developmental time and constitutes part of a maturation process that governs morphological segmentation in conjunction with the clock. Segment morphogenesis involves a mesenchymal to epithelial transition as prospective border cells at the anterior end of the mesenchymal PSM adopt a polarized, columnar morphology and surround a mesenchymal core of cells. The segmental pattern influences the development of the somite derivatives such as the myotome, and the myotome reciprocates to affect the formation of segment boundaries. While somites appear to be serially homologous, there may be variation in the segmentation mechanism along the body axis. Moreover, whereas the genetic architecture of the zebrafish, mouse, and chick segmentation clocks shares many common elements, there is evidence that the gene networks have undergone independent modification during evolution.
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Affiliation(s)
- Scott A Holley
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut 06520, USA.
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28
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Affiliation(s)
- Iain A Drummond
- Department of Medicine, Harvard Medical School and Renal Unit, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA
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29
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Abstract
Since the first forkhead (Fox) gene was identified, the importance of this family of transcription factors has increased steadily with the discoveries of the diverse range of developmental processes that they regulate in eukaryotes. Among other processes, the Fox factors are important in the establishment of the body axis and the development of tissues from all three germ layers. In this article, we present some of the recent data on this gene family with reference to selected phenotypes observed in patients and model organisms, and the sensitivity of developmental processes to alterations in forkhead gene dosage.
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Affiliation(s)
- Ordan J Lehmann
- Department of Molecular Genetics, Institute of Ophthalmology, London EC1V 9EL, UK.
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30
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Solomon KS, Kudoh T, Dawid IB, Fritz A. Zebrafish foxi1 mediates otic placode formation and jaw development. Development 2003; 130:929-40. [PMID: 12538519 DOI: 10.1242/dev.00308] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The otic placode is a transient embryonic structure that gives rise to the inner ear. Although inductive signals for otic placode formation have been characterized, less is known about the molecules that respond to these signals within otic primordia. Here, we identify a mutation in zebrafish, hearsay, which disrupts the initiation of placode formation. We show that hearsay disrupts foxi1, a forkhead domain-containing gene, which is expressed in otic precursor cells before placodes become visible; foxi1 appears to be the earliest marker known for the otic anlage. We provide evidence that foxi1 regulates expression of pax8, indicating a very early role for this gene in placode formation. In addition, foxi1 is expressed in the developing branchial arches, and jaw formation is disrupted in hearsay mutant embryos.
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Affiliation(s)
- Keely S Solomon
- Department of Biology, Emory University, Atlanta, GA 30322, USA
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31
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Berry FB, Saleem RA, Walter MA. FOXC1 transcriptional regulation is mediated by N- and C-terminal activation domains and contains a phosphorylated transcriptional inhibitory domain. J Biol Chem 2002; 277:10292-7. [PMID: 11782474 DOI: 10.1074/jbc.m110266200] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Mutations in the FOXC1 gene result in Axenfeld-Rieger malformations of the anterior segment of the eye and lead to an increased susceptibility of glaucoma. To understand how the FOXC1 protein may function in contributing to these malformations, we identified functional regions in FOXC1 required for nuclear localization and transcriptional regulation. Two regions in the FOXC1 forkhead domain, one rich in basic amino acid residues, and a second, highly conserved among all FOX proteins, were necessary for nuclear localization of the FOXC1 protein. However, only the basic region was sufficient for nuclear localization. Two transcriptional activation domains were identified in the extreme N- and C-terminal regions of FOXC1. A transcription inhibitory domain was located at the central region of the protein. This region was able to reduce the trans-activation potential of the C-terminal activation domain, as well as the GAL4 activation domain. Lastly, we demonstrate that FOXC1 is a phosphoprotein, and a number of residues predicted to be phosphorylated were localized to the FOXC1 inhibitory domain. Removal of residues 215-366 resulted in a transcriptionally hyperactive FOXC1 protein, which displayed a reduced level of phosphorylation. These results indicate that FOXC1 is under complex regulatory control with multiple functional domains modulating FOXC1 transcriptional regulation.
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Affiliation(s)
- Fred B Berry
- Department of Ophthalmology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada.
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32
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Topczewska JM, Topczewski J, Shostak A, Kume T, Solnica-Krezel L, Hogan BL. The winged helix transcription factor Foxc1a is essential for somitogenesis in zebrafish. Genes Dev 2001; 15:2483-93. [PMID: 11562356 PMCID: PMC312789 DOI: 10.1101/gad.907401] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Previous studies identified zebrafish foxc1a and foxc1b as homologs of the mouse forkhead gene, Foxc1. Both genes are transcribed in the unsegmented presomitic mesoderm (PSM), newly formed somites, adaxial cells, and head mesoderm. Here, we show that inhibiting synthesis of Foxc1a (but not Foxc1b) protein with two different morpholino antisense oligonucleotides blocks formation of morphological somites, segment boundaries, and segmented expression of genes normally transcribed in anterior and posterior somites and expression of paraxis implicated in somite epithelialization. Patterning of the anterior PSM is also affected, as judged by the absence of mesp-b, ephrinB2, and ephA4 expression, and the down-regulation of notch5 and notch6. In contrast, the expression of other genes, including mesp-a and papc, in the anterior of somite primordia, and the oscillating expression of deltaC and deltaD in the PSM appear normal. Nevertheless, this expression is apparently insufficient for the maturation of the presumptive somites to proceed to the stage when boundary formation occurs or for the maintenance of anterior/posterior patterning. Mouse embryos that are compound null mutants for Foxc1 and the closely related Foxc2 have no morphological somites and show abnormal expression of Notch signaling pathway genes in the anterior PSM. Therefore, zebrafish foxc1a plays an essential and conserved role in somite formation, regulating both the expression of paraxis and the A/P patterning of somite primordia.
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Affiliation(s)
- J M Topczewska
- Department of Cell Biology and Howard Hughes Medical Institute, Vanderbilt Medical Center, Nashville, Tennessee 37232-2175, USA
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