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Abu Nahia K, Sulej A, Migdał M, Ochocka N, Ho R, Kamińska B, Zagorski M, Winata CL. scRNA-seq reveals the diversity of the developing cardiac cell lineage and molecular players in heart rhythm regulation. iScience 2024; 27:110083. [PMID: 38872974 PMCID: PMC11170199 DOI: 10.1016/j.isci.2024.110083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 01/26/2024] [Accepted: 05/20/2024] [Indexed: 06/15/2024] Open
Abstract
We utilized scRNA-seq to delineate the diversity of cell types in the zebrafish heart. Transcriptome profiling of over 50,000 cells at 48 and 72 hpf defined at least 18 discrete cell lineages of the developing heart. Utilizing well-established gene signatures, we identified a population of cells likely to be the primary pacemaker and characterized the transcriptome profile defining this critical cell type. Two previously uncharacterized genes, atp1b3b and colec10, were found to be enriched in the sinoatrial cardiomyocytes. CRISPR/Cas9-mediated knockout of these two genes significantly reduced heart rate, implicating their role in cardiac development and conduction. Additionally, we describe other cardiac cell lineages, including the endothelial and neural cells, providing their expression profiles as a resource. Our results established a detailed atlas of the developing heart, providing valuable insights into cellular and molecular mechanisms, and pinpointed potential new players in heart rhythm regulation.
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Affiliation(s)
- Karim Abu Nahia
- International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Agata Sulej
- International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Maciej Migdał
- International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Natalia Ochocka
- Laboratory of Molecular Neurobiology, Nencki Institute of Experimental Biology, Warsaw, Poland
| | - Richard Ho
- Institute of Theoretical Physics and Mark Kac Center for Complex Systems Research, Jagiellonian University, Cracow, Poland
- The Njord Centre, Department of Physics, University of Oslo, Oslo, Norway
| | - Bożena Kamińska
- Laboratory of Molecular Neurobiology, Nencki Institute of Experimental Biology, Warsaw, Poland
| | - Marcin Zagorski
- Institute of Theoretical Physics and Mark Kac Center for Complex Systems Research, Jagiellonian University, Cracow, Poland
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2
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Rossmann MP, Palis J. Developmental regulation of primitive erythropoiesis. Curr Opin Hematol 2024; 31:71-81. [PMID: 38415349 DOI: 10.1097/moh.0000000000000806] [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] [Indexed: 02/29/2024]
Abstract
PURPOSE OF REVIEW In this review, we present an overview of recent studies of primitive erythropoiesis, focusing on advances in deciphering its embryonic origin, defining species-specific differences in its developmental regulation, and better understanding the molecular and metabolic pathways involved in terminal differentiation. RECENT FINDINGS Single-cell transcriptomics combined with state-of-the-art lineage tracing approaches in unperturbed murine embryos have yielded new insights concerning the origin of the first (primitive) erythroid cells that arise from mesoderm-derived progenitors. Moreover, studies examining primitive erythropoiesis in rare early human embryo samples reveal an overall conservation of primitive erythroid ontogeny in mammals, albeit with some interesting differences such as localization of erythropoietin (EPO) production in the early embryo. Mechanistically, the repertoire of transcription factors that critically regulate primitive erythropoiesis has been expanded to include regulators of transcription elongation, as well as epigenetic modifiers such as the histone methyltransferase DOT1L. For the latter, noncanonical roles aside from enzymatic activity are being uncovered. Lastly, detailed surveys of the metabolic and proteomic landscape of primitive erythroid precursors reveal the activation of key metabolic pathways such as pentose phosphate pathway that are paralleled by a striking loss of mRNA translation machinery. SUMMARY The ability to interrogate single cells in vivo continues to yield new insights into the birth of the first essential organ system of the developing embryo. A comparison of the regulation of primitive and definitive erythropoiesis, as well as the interplay of the different layers of regulation - transcriptional, epigenetic, and metabolic - will be critical in achieving the goal of faithfully generating erythroid cells in vitro for therapeutic purposes.
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Affiliation(s)
- Marlies P Rossmann
- Department of Biomedical Genetics and Wilmot Cancer Institute, University of Rochester Medical Center
| | - James Palis
- Department of Pediatrics, University of Rochester Medical Center, Rochester, New York, USA
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3
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Zhang X, Yang Y, Wei Y, Zhao Q, Lou X. blf and the drl cluster synergistically regulate cell fate commitment during zebrafish primitive hematopoiesis. Development 2022; 149:285945. [PMID: 36420817 DOI: 10.1242/dev.200919] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 11/14/2022] [Indexed: 11/25/2022]
Abstract
Hematopoiesis is a highly coordinated process that generates all the body's blood cells, and perturbations in embryonic hematopoiesis may result in illnesses ranging from fetal anemia to various leukemias. Correct establishment of hematopoietic progenitor cell fate is essential for the development of adequate blood cell subpopulations, although regulators of cell fate commitment have not been fully defined. Here, we show that primary erythropoiesis and myelopoiesis in zebrafish embryos are synergistically regulated by blf and the drl cluster, as simultaneous depletion led to severe erythrocyte aplasia and excessive macrophage formation at the expense of neutrophil development. Integrative analysis of transcriptome- and genome-wide binding data revealed that blf and drl cluster genes are responsible for constraining the expression of vasculogenesis-promoting genes in the intermediate cell mass and monocytopoiesis-promoting genes in the rostral blood island. This indicates that blf and drl cluster genes act as determinants of the fate commitment of erythroid and myeloid progenitor cells. Furthermore, a rescue screen demonstrated that Zfp932 is a potential mammalian functional equivalent to zebrafish blf and drl cluster genes. Our data provide insight into conserved cell fate commitment mechanisms of primitive hematopoiesis.
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Affiliation(s)
- Xue Zhang
- Medical School, Nanjing University, Nanjing, 210093, China
| | - Yuxi Yang
- Medical School, Nanjing University, Nanjing, 210093, China
| | - Yuxuan Wei
- Medical School, Nanjing University, Nanjing, 210093, China
| | - Qingshun Zhao
- Medical School, Nanjing University, Nanjing, 210093, China
| | - Xin Lou
- Research Institute of Intelligent Computing, Zhejiang Lab, Hangzhou, 311100, China
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4
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Murat El Houdigui S, Adam-Guillermin C, Armant O. Ionising Radiation Induces Promoter DNA Hypomethylation and Perturbs Transcriptional Activity of Genes Involved in Morphogenesis during Gastrulation in Zebrafish. Int J Mol Sci 2020; 21:ijms21114014. [PMID: 32512748 PMCID: PMC7312202 DOI: 10.3390/ijms21114014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 05/28/2020] [Accepted: 06/01/2020] [Indexed: 12/22/2022] Open
Abstract
Embryonic development is particularly vulnerable to stress and DNA damage, as mutations can accumulate through cell proliferation in a wide number of cells and organs. However, the biological effects of chronic exposure to ionising radiation (IR) at low and moderate dose rates (< 6 mGy/h) remain largely controversial, raising concerns for environmental protection. The present study focuses on the molecular effects of IR (0.005 to 50 mGy/h) on zebrafish embryos at the gastrula stage (6 hpf), at both the transcriptomics and epigenetics levels. Our results show that exposure to IR modifies the expression of genes involved in mitochondrial activity from 0.5 to 50 mGy/h. In addition, important developmental pathways, namely, the Notch, retinoic acid, BMP and Wnt signalling pathways, were altered at 5 and 50 mGy/h. Transcriptional changes of genes involved in the morphogenesis of the ectoderm and mesoderm were detected at all dose rates, but were prominent from 0.5 to 50 mGy/h. At the epigenetic level, exposure to IR induced a hypomethylation of DNA in the promoter of genes that colocalised with both H3K27me3 and H3Kme4 histone marks and correlated with changes in transcriptional activity. Finally, pathway enrichment analysis demonstrated that the DNA methylation changes occurred in the promoter of important developmental genes, including morphogenesis of the ectoderm and mesoderm. Together, these results show that the transcriptional program regulating morphogenesis in gastrulating embryos was modified at dose rates greater than or equal to 0.5 mGy/h, which might predict potential neurogenesis and somitogenesis defects observed at similar dose rates later in development.
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Affiliation(s)
- Sophia Murat El Houdigui
- PSE-ENV/SRTE/LECO, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Cadarache, 13115 Saint-Paul-Lez-Durance, France;
| | - Christelle Adam-Guillermin
- PSE-SANTE/SDOS/LMDN, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Cadarache, 13115 Saint-Paul-Lez-Durance, France;
| | - Olivier Armant
- PSE-ENV/SRTE/LECO, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Cadarache, 13115 Saint-Paul-Lez-Durance, France;
- Correspondence:
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5
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Prummel KD, Hess C, Nieuwenhuize S, Parker HJ, Rogers KW, Kozmikova I, Racioppi C, Brombacher EC, Czarkwiani A, Knapp D, Burger S, Chiavacci E, Shah G, Burger A, Huisken J, Yun MH, Christiaen L, Kozmik Z, Müller P, Bronner M, Krumlauf R, Mosimann C. A conserved regulatory program initiates lateral plate mesoderm emergence across chordates. Nat Commun 2019; 10:3857. [PMID: 31451684 PMCID: PMC6710290 DOI: 10.1038/s41467-019-11561-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/22/2019] [Indexed: 01/06/2023] Open
Abstract
Cardiovascular lineages develop together with kidney, smooth muscle, and limb connective tissue progenitors from the lateral plate mesoderm (LPM). How the LPM initially emerges and how its downstream fates are molecularly interconnected remain unknown. Here, we isolate a pan-LPM enhancer in the zebrafish-specific draculin (drl) gene that provides specific LPM reporter activity from early gastrulation. In toto live imaging and lineage tracing of drl-based reporters captures the dynamic LPM emergence as lineage-restricted mesendoderm field. The drl pan-LPM enhancer responds to the transcription factors EomesoderminA, FoxH1, and MixL1 that combined with Smad activity drive LPM emergence. We uncover specific activity of zebrafish-derived drl reporters in LPM-corresponding territories of several chordates including chicken, axolotl, lamprey, Ciona, and amphioxus, revealing a universal upstream LPM program. Altogether, our work provides a mechanistic framework for LPM emergence as defined progenitor field, possibly representing an ancient mesodermal cell state that predates the primordial vertebrate embryo. Numerous tissues are derived from the lateral plate mesoderm (LPM) but how this is specified is unclear. Here, the authors identify a pan-LPM reporter activity found in the zebrafish draculin (drl) gene that also shows transgenic activity in LPM-corresponding territories of several chordates, including chicken, axolotl, lamprey, Ciona, and amphioxus.
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Affiliation(s)
- Karin D Prummel
- Institute of Molecular Life Sciences, University of Zurich, Zürich, 8057, Switzerland
| | - Christopher Hess
- Institute of Molecular Life Sciences, University of Zurich, Zürich, 8057, Switzerland
| | - Susan Nieuwenhuize
- Institute of Molecular Life Sciences, University of Zurich, Zürich, 8057, Switzerland
| | - Hugo J Parker
- Department of Anatomy and Cell Biology, Kansas University Medical Center, Kansas City, KS, 66160, USA.,Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
| | - Katherine W Rogers
- Friedrich Miescher Laboratory of the Max Planck Society, Tübingen, 72076, Germany
| | - Iryna Kozmikova
- Institute of Molecular Genetics of the ASCR, Prague, 142 20, Czech Republic
| | - Claudia Racioppi
- Center for Developmental Genetics, Department of Biology, New York University, New York, NY, 10003, USA
| | - Eline C Brombacher
- Institute of Molecular Life Sciences, University of Zurich, Zürich, 8057, Switzerland
| | - Anna Czarkwiani
- TUD-CRTD Center for Regenerative Therapies Dresden, Dresden, 01307, Germany
| | - Dunja Knapp
- TUD-CRTD Center for Regenerative Therapies Dresden, Dresden, 01307, Germany
| | - Sibylle Burger
- Institute of Molecular Life Sciences, University of Zurich, Zürich, 8057, Switzerland
| | - Elena Chiavacci
- Institute of Molecular Life Sciences, University of Zurich, Zürich, 8057, Switzerland
| | - Gopi Shah
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, 01307, Germany
| | - Alexa Burger
- Institute of Molecular Life Sciences, University of Zurich, Zürich, 8057, Switzerland
| | - Jan Huisken
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, 01307, Germany.,Morgridge Institute for Research, Madison, WI, 53715, USA
| | - Maximina H Yun
- TUD-CRTD Center for Regenerative Therapies Dresden, Dresden, 01307, Germany.,Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, 01307, Germany
| | - Lionel Christiaen
- Center for Developmental Genetics, Department of Biology, New York University, New York, NY, 10003, USA
| | - Zbynek Kozmik
- Institute of Molecular Genetics of the ASCR, Prague, 142 20, Czech Republic
| | - Patrick Müller
- Friedrich Miescher Laboratory of the Max Planck Society, Tübingen, 72076, Germany
| | - Marianne Bronner
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Robb Krumlauf
- Department of Anatomy and Cell Biology, Kansas University Medical Center, Kansas City, KS, 66160, USA.,Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
| | - Christian Mosimann
- Institute of Molecular Life Sciences, University of Zurich, Zürich, 8057, Switzerland.
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6
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Miles LB, Darido C, Kaslin J, Heath JK, Jane SM, Dworkin S. Mis-expression of grainyhead-like transcription factors in zebrafish leads to defects in enveloping layer (EVL) integrity, cellular morphogenesis and axial extension. Sci Rep 2017; 7:17607. [PMID: 29242584 PMCID: PMC5730563 DOI: 10.1038/s41598-017-17898-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 12/01/2017] [Indexed: 02/07/2023] Open
Abstract
The grainyhead-like (grhl) transcription factors play crucial roles in craniofacial development, epithelial morphogenesis, neural tube closure, and dorso-ventral patterning. By utilising the zebrafish to differentially regulate expression of family members grhl2b and grhl3, we show that both genes regulate epithelial migration, particularly convergence-extension (CE) type movements, during embryogenesis. Genetic deletion of grhl3 via CRISPR/Cas9 results in failure to complete epiboly and pre-gastrulation embryonic rupture, whereas morpholino (MO)-mediated knockdown of grhl3 signalling leads to aberrant neural tube morphogenesis at the midbrain-hindbrain boundary (MHB), a phenotype likely due to a compromised overlying enveloping layer (EVL). Further disruptions of grhl3-dependent pathways (through co-knockdown of grhl3 with target genes spec1 and arhgef19) confirm significant MHB morphogenesis and neural tube closure defects. Concomitant MO-mediated disruption of both grhl2b and grhl3 results in further extensive CE-like defects in body patterning, notochord and somite morphogenesis. Interestingly, over-expression of either grhl2b or grhl3 also leads to numerous phenotypes consistent with disrupted cellular migration during gastrulation, including embryo dorsalisation, axial duplication and impaired neural tube migration leading to cyclopia. Taken together, our study ascribes novel roles to the Grhl family in the context of embryonic development and morphogenesis.
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Affiliation(s)
- Lee B Miles
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Bundoora, VIC, 3086, Australia
| | - Charbel Darido
- The Victorian Comprehensive Cancer Centre, Peter MacCallum Cancer Centre, Parkville, VIC, 3050, Australia
| | - Jan Kaslin
- The Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, 3168, Australia
| | - Joan K Heath
- Department of Chemical Biology, The Walter and Eliza Hall Institute, Parkville, VIC, 3050, Australia
| | - Stephen M Jane
- Department of Medicine, Monash University Central Clinical School, Prahran, VIC 3181, Australia.,Department of Hematology, Alfred Hospital, Prahran, VIC 3181, Australia
| | - Sebastian Dworkin
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Bundoora, VIC, 3086, Australia.
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7
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Lim FT, Ogawa S, Smith AI, Parhar IS. Proteomics Identification of Potential Candidates Involved in Cell Proliferation for Early Stage of Brain Regeneration in the Adult Zebrafish. Zebrafish 2017; 14:10-22. [DOI: 10.1089/zeb.2016.1319] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Affiliation(s)
- Fei Tieng Lim
- Brain Research Institute, Jeffrey Cheah School of Medicine and Health Science, Monash University Malaysia, Bandar Sunway, Malaysia
| | - Satoshi Ogawa
- Brain Research Institute, Jeffrey Cheah School of Medicine and Health Science, Monash University Malaysia, Bandar Sunway, Malaysia
| | - A. Ian Smith
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Australia
| | - Ishwar S. Parhar
- Brain Research Institute, Jeffrey Cheah School of Medicine and Health Science, Monash University Malaysia, Bandar Sunway, Malaysia
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8
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Pimtong W, Datta M, Ulrich AM, Rhodes J. Drl.3 governs primitive hematopoiesis in zebrafish. Sci Rep 2014; 4:5791. [PMID: 25051985 PMCID: PMC4107348 DOI: 10.1038/srep05791] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 06/19/2014] [Indexed: 12/16/2022] Open
Abstract
The molecular program controlling hematopoietic differentiation is not fully understood. Here, we describe a family of zebrafish genes that includes a novel hematopoietic regulator, draculin-like 3 (drl.3). We found that drl.3 is expressed in mesoderm-derived hematopoietic cells and is retained during erythroid maturation. Moreover, drl.3 expression correlated with erythroid development in gata1a- and spi1b-depleted embryos. Loss-of-function analysis indicated that drl.3 plays an essential role in primitive erythropoiesis and, to a lesser extent, myelopoiesis that is independent of effects on vasculature, emergence of primitive and definitive progenitor cells and cell viability. While drl.3 depletion reduced gata1a expression and inhibited erythroid development, enforced expression of gata1a was not sufficient to rescue erythropoiesis, indicating that the regulation of hematopoiesis by drl.3 extends beyond control of gata1a expression. Knockdown of drl.3 increased the proportion of less differentiated, primitive hematopoietic cells without affecting proliferation, establishing drl.3 as an important regulator of primitive hematopoietic cell differentiation.
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Affiliation(s)
- Wittaya Pimtong
- 1] Immune Cell Development and Host Defense Program, Fox Chase Cancer Center, Temple University Health System, Philadelphia, PA, 19111, USA [2]
| | - Madhusmita Datta
- 1] Immune Cell Development and Host Defense Program, Fox Chase Cancer Center, Temple University Health System, Philadelphia, PA, 19111, USA [2]
| | - Allison M Ulrich
- Immune Cell Development and Host Defense Program, Fox Chase Cancer Center, Temple University Health System, Philadelphia, PA, 19111, USA
| | - Jennifer Rhodes
- Immune Cell Development and Host Defense Program, Fox Chase Cancer Center, Temple University Health System, Philadelphia, PA, 19111, USA
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9
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Palencia-Desai S, Kohli V, Kang J, Chi NC, Black BL, Sumanas S. Vascular endothelial and endocardial progenitors differentiate as cardiomyocytes in the absence of Etsrp/Etv2 function. Development 2011; 138:4721-32. [PMID: 21989916 DOI: 10.1242/dev.064998] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Previous studies have suggested that embryonic vascular endothelial, endocardial and myocardial lineages originate from multipotential cardiovascular progenitors. However, their existence in vivo has been debated and molecular mechanisms that regulate specification of different cardiovascular lineages are poorly understood. An ETS domain transcription factor Etv2/Etsrp/ER71 has been recently established as a crucial regulator of vascular endothelial differentiation in zebrafish and mouse embryos. In this study, we show that etsrp-expressing vascular endothelial/endocardial progenitors differentiate as cardiomyocytes in the absence of Etsrp function during zebrafish embryonic development. Expression of multiple endocardial specific markers is absent or greatly reduced in Etsrp knockdown or mutant embryos. We show that Etsrp regulates endocardial differentiation by directly inducing endocardial nfatc1 expression. In addition, Etsrp function is required to inhibit myocardial differentiation. In the absence of Etsrp function, etsrp-expressing endothelial and endocardial progenitors initiate myocardial marker hand2 and cmlc2 expression. Furthermore, Foxc1a function and interaction between Foxc1a and Etsrp is required to initiate endocardial development, but is dispensable for the inhibition of myocardial differentiation. These results argue that Etsrp initiates endothelial and endocardial, and inhibits myocardial, differentiation by two distinct mechanisms. Our findings are important for the understanding of genetic pathways that control cardiovascular differentiation during normal vertebrate development and will also greatly contribute to the stem cell research aimed at regenerating heart tissues.
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Affiliation(s)
- Sharina Palencia-Desai
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
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10
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Pei W, Feldman B. Identification of common and unique modifiers of zebrafish midline bifurcation and cyclopia. Dev Biol 2008; 326:201-11. [PMID: 19046963 DOI: 10.1016/j.ydbio.2008.11.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Revised: 11/10/2008] [Accepted: 11/10/2008] [Indexed: 01/26/2023]
Abstract
Loss of the zebrafish Nodal-related protein Squint causes a spectrum of phenotypes including cyclopia and midline bifurcations (MB). Here we examine MBs and their relation to cyclopia in maternal-zygotic squint (MZsqt) mutants. There is a concordance of MB with cyclopia in MZsqt embryos. Heat treatment and depletion of Hsp90a are "common" risk factors, each of which increases the incidence of both phenotypes. Midline identity is specified on both sides of MBs, and deep-layer cells are initially lacking within bifurcations, whereas enveloping layer cells are intact. Bifurcations do not appear until the completion of gastrulation and are preceded by gaps in the expression of wnt5b, an essential regulator of dorsal convergence. The incidence of early MBs and wnt5b expression defects in heated MZsqt embryos is high, but there is also substantial recovery. Wnt5b depletion increases the incidence of MB, but not cyclopia, and as such Wnt5b is a "unique" risk factor for MB. Reciprocally, depletion of Wnt11 or Hsp90b increases cyclopia only. In summary, we find that MB arises after gastrulation in regions that fail to express wnt5b, and we show that two complex dysmorphologies - MB and cyclopia - can be promoted by either common or unique risk factors.
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Affiliation(s)
- Wuhong Pei
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, 9000 Rockville Pike, Building 35, Room 1B 205, Bethesda, MD 20892, USA
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11
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García-García MJ, Shibata M, Anderson KV. Chato, a KRAB zinc-finger protein, regulates convergent extension in the mouse embryo. Development 2008; 135:3053-62. [PMID: 18701545 DOI: 10.1242/dev.022897] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In Xenopus and zebrafish embryos, elongation of the anterior-posterior body axis depends on convergent extension, a process that involves polarized cell movements and is regulated by non-canonical Wnt signaling. The mechanisms that control axis elongation of the mouse embryo are much less well understood. Here, we characterize the ENU-induced mouse mutation chato, which causes arrest at midgestation and defects characteristic of convergent extension mutants, including a shortened body axis, mediolaterally extended somites and an open neural tube. The chato mutation disrupts Zfp568, a Krüppel-associated box (KRAB) domain zinc-finger protein. Morphometric analysis revealed that the definitive endoderm of mouse wild-type embryos undergoes cell rearrangements that lead to convergent extension during early somite stages, and that these cell rearrangements fail in chato embryos. Although non-canonical Wnt signaling is important for convergent extension in the mouse notochord and neural plate, the results indicate that chato regulates body axis elongation in all embryonic tissues through a process independent of non-canonical Wnt signaling.
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Affiliation(s)
- María J García-García
- Molecular Biology and Genetics Department, Cornell University, Ithaca, NY 14853, USA.
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12
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Recent papers on zebrafish and other aquarium fish models. Zebrafish 2008; 2:125-37. [PMID: 18248172 DOI: 10.1089/zeb.2005.2.125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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