1
|
Afouda BA. Towards Understanding the Gene-Specific Roles of GATA Factors in Heart Development: Does GATA4 Lead the Way? Int J Mol Sci 2022; 23:5255. [PMID: 35563646 PMCID: PMC9099915 DOI: 10.3390/ijms23095255] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 04/29/2022] [Accepted: 05/03/2022] [Indexed: 02/04/2023] Open
Abstract
Transcription factors play crucial roles in the regulation of heart induction, formation, growth and morphogenesis. Zinc finger GATA transcription factors are among the critical regulators of these processes. GATA4, 5 and 6 genes are expressed in a partially overlapping manner in developing hearts, and GATA4 and 6 continue their expression in adult cardiac myocytes. Using different experimental models, GATA4, 5 and 6 were shown to work together not only to ensure specification of cardiac cells but also during subsequent heart development. The complex involvement of these related gene family members in those processes is demonstrated through the redundancy among them and crossregulation of each other. Our recent identification at the genome-wide level of genes specifically regulated by each of the three family members and our earlier discovery that gata4 and gata6 function upstream, while gata5 functions downstream of noncanonical Wnt signalling during cardiac differentiation, clearly demonstrate the functional differences among the cardiogenic GATA factors. Such suspected functional differences are worth exploring more widely. It appears that in the past few years, significant advances have indeed been made in providing a deeper understanding of the mechanisms by which each of these molecules function during heart development. In this review, I will therefore discuss current evidence of the role of individual cardiogenic GATA factors in the process of heart development and emphasize the emerging central role of GATA4.
Collapse
Affiliation(s)
- Boni A Afouda
- Institute of Medical Sciences, Foresterhill Health Campus, University of Aberdeen, Aberdeen AB25 2ZD, Scotland, UK
| |
Collapse
|
2
|
Jansen C, Paraiso KD, Zhou JJ, Blitz IL, Fish MB, Charney RM, Cho JS, Yasuoka Y, Sudou N, Bright AR, Wlizla M, Veenstra GJC, Taira M, Zorn AM, Mortazavi A, Cho KWY. Uncovering the mesendoderm gene regulatory network through multi-omic data integration. Cell Rep 2022; 38:110364. [PMID: 35172134 PMCID: PMC8917868 DOI: 10.1016/j.celrep.2022.110364] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 10/30/2021] [Accepted: 01/19/2022] [Indexed: 01/01/2023] Open
Abstract
Mesendodermal specification is one of the earliest events in embryogenesis, where cells first acquire distinct identities. Cell differentiation is a highly regulated process that involves the function of numerous transcription factors (TFs) and signaling molecules, which can be described with gene regulatory networks (GRNs). Cell differentiation GRNs are difficult to build because existing mechanistic methods are low throughput, and high-throughput methods tend to be non-mechanistic. Additionally, integrating highly dimensional data composed of more than two data types is challenging. Here, we use linked self-organizing maps to combine chromatin immunoprecipitation sequencing (ChIP-seq)/ATAC-seq with temporal, spatial, and perturbation RNA sequencing (RNA-seq) data from Xenopus tropicalis mesendoderm development to build a high-resolution genome scale mechanistic GRN. We recover both known and previously unsuspected TF-DNA/TF-TF interactions validated through reporter assays. Our analysis provides insights into transcriptional regulation of early cell fate decisions and provides a general approach to building GRNs using highly dimensional multi-omic datasets.
Collapse
Affiliation(s)
- Camden Jansen
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA; Center for Complex Biological Systems, University of California, Irvine, CA, USA
| | - Kitt D Paraiso
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA; Center for Complex Biological Systems, University of California, Irvine, CA, USA
| | - Jeff J Zhou
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Ira L Blitz
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Margaret B Fish
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Rebekah M Charney
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Jin Sun Cho
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Yuuri Yasuoka
- Laboratory for Comprehensive Genomic Analysis, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Norihiro Sudou
- Department of Anatomy, School of Medicine, Toho University, Tokyo, Japan
| | - Ann Rose Bright
- Department of Molecular Developmental Biology, Radboud University, Nijmegen, the Netherlands
| | - Marcin Wlizla
- Division of Developmental Biology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Gert Jan C Veenstra
- Department of Molecular Developmental Biology, Radboud University, Nijmegen, the Netherlands
| | - Masanori Taira
- Department of Biological Sciences, Chuo University, Tokyo, Japan
| | - Aaron M Zorn
- Division of Developmental Biology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Ali Mortazavi
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA; Center for Complex Biological Systems, University of California, Irvine, CA, USA.
| | - Ken W Y Cho
- Department of Developmental and Cell Biology, University of California, Irvine, CA, USA; Center for Complex Biological Systems, University of California, Irvine, CA, USA.
| |
Collapse
|
3
|
Miyakawa M, Katada T, Numa Y, Kinoshita T. Transcriptional regulatory elements of hif1α in a distal locus of islet1 in Xenopus laevis. Comp Biochem Physiol B Biochem Mol Biol 2021; 255:110598. [PMID: 33785414 DOI: 10.1016/j.cbpb.2021.110598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 03/12/2021] [Accepted: 03/24/2021] [Indexed: 11/28/2022]
Abstract
Adult mammalian hearts are not regenerative. However, recent studies have evidenced that hypoxia enhances their regeneration. Islet1 (isl1) is known as a cardiac progenitor marker, which is quiescent in adult mammal hearts. In Xenopus hearts, transcriptional activation of isl1 was shown during cardiac regeneration of froglets at 3 months after metamorphosis. In this study, we examined transcriptional regulation of isl1 focusing on hypoxia-inducible factor 1α (hif1α) in Xenopus heart. We found that hif1α expression was increased in response to cardiac injury and overexpression of hif1α upregulated mRNA expression of isl1. Multiple conservation analysis including 9 species revealed that 8 multiple conserved regions (MCRs) were present upstream of isl1. DNA sequence analysis using JASPAR showed hif1α binding motifs in MCRs. By luciferase reporter assay and chromatin immunoprecipitation analysis, we found that hif1α directly bound to hif1α motifs in the most distant MCR8 and showed a specific transcriptional activity on the MCR8. In the luciferase assay using constructs carrying MCR8 without a responsive motif of hif1α, the reporter activity was lost. Pharmacologically inhibition of hif1α affected isl1 transcription and downstream events including cardiac phenotypes, suggesting functional defects of islet1. Contrarily in murine hearts, transcription of isl1 was unresponsive even after cryoinjury to adult hearts while hif1α mRNA was induced. In comparative analysis of multiple alignment, hif1α elements present in MCR8 of Xenopus or zebrafish were found to be disrupted as species are evolutionarily distant from Xenopus and zebrafish. Our results suggested an altered switch of isl1 transcription between mammals and Xenopus laevis.
Collapse
Affiliation(s)
- Miho Miyakawa
- Department of Life Science, Faculty of Science, Rikkyo University, Tokyo 171-8501, Japan
| | - Tomohisa Katada
- Department of Pharmacology and Toxicology, Kyorin University School of Medicine, Tokyo 181-8611, Japan
| | - Yunosuke Numa
- Department of Life Science, Faculty of Science, Rikkyo University, Tokyo 171-8501, Japan
| | - Tsutomu Kinoshita
- Department of Life Science, Faculty of Science, Rikkyo University, Tokyo 171-8501, Japan.
| |
Collapse
|
4
|
Wei W, Pan S, Ma Y, Xiao Y, Yang Y, He S, Bravo A, Soberón M, Liu K. GATAe transcription factor is involved in Bacillus thuringiensis Cry1Ac toxin receptor gene expression inducing toxin susceptibility. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2020; 118:103306. [PMID: 31843687 DOI: 10.1016/j.ibmb.2019.103306] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 12/09/2019] [Accepted: 12/10/2019] [Indexed: 06/10/2023]
Abstract
The insecticidal Cry toxins produced by Bacillus thuringiensis (Bt) are powerful tools for insect control. Cry toxin receptors such as cadherin (CAD), ABCC2 transporter and alkaline phosphatase (ALP), located on insect midgut cells, are needed for Cry toxicity. Although insect cell lines are useful experimental models for elucidating toxin action mechanism, most of them show low expression of Cry-receptors genes. The GATA transcription factor family plays important roles in regulating development and differentiation of intestine stem cells. Here, we investigated whether GATAs transcription factors are involved in the expression of Cry1Ac-receptors genes, using multiple insect cell lines. Four GATA genes were identified in the transcriptome of the midgut tissue from the lepidopteran larvae Helicoverpa armigera. These HaGATA genes were transiently expressed in three lepidopteran cell lines, Spodoptera frugiperda Sf9, H. armigera QB-Ha-E5 and Trichoplusia ni Hi5. Analysis of transcription activity using transcriptional gene-fusions showed that only H. armigera GATAe (HaGATAe) significantly increased the transcription of CAD, ABCC2 and ALP receptors genes in all insect cell lines. Key DNA regions for HaGATAe regulation were identified in the promoter sequence of these Cry-receptors genes by using promoter deletion mapping. The transient expression of HaGATAe in these cell lines, conferred sensitivity to Cry1Ac toxin, although in Hi5 cells the susceptibility to Cry1Ac was lower than in other two cell lines. High sensitivity to Cry1Ac correlated with simultaneous transcription of ABCC2 and CAD genes in Sf9 and QB-Ha-E5 cells. Our results reveal that HaGATAe enhances transcription of several lepidopteran Cry1Ac receptor genes in cultured insect cells.
Collapse
Affiliation(s)
- Wei Wei
- School of Life Sciences, Central China Normal University, Wuhan, 430070, China
| | - Shuang Pan
- School of Life Sciences, Central China Normal University, Wuhan, 430070, China
| | - Yuemin Ma
- School of Life Sciences, Central China Normal University, Wuhan, 430070, China
| | - Yutao Xiao
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Yongbo Yang
- School of Life Sciences, Central China Normal University, Wuhan, 430070, China
| | - Sijia He
- School of Life Sciences, Central China Normal University, Wuhan, 430070, China
| | - Alejandra Bravo
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, 62250, Morelos, Mexico
| | - Mario Soberón
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, 62250, Morelos, Mexico.
| | - Kaiyu Liu
- School of Life Sciences, Central China Normal University, Wuhan, 430070, China.
| |
Collapse
|
5
|
Afouda BA, Lynch AT, de Paiva Alves E, Hoppler S. Genome-wide transcriptomics analysis of genes regulated by GATA4, 5 and 6 during cardiomyogenesis in Xenopus laevis. Data Brief 2018; 17:559-563. [PMID: 29876429 PMCID: PMC5988223 DOI: 10.1016/j.dib.2018.01.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 12/18/2017] [Accepted: 01/04/2018] [Indexed: 11/26/2022] Open
Abstract
The transcription factors GATA4, GATA5 and GATA6 play important roles in heart muscle differentiation. The data presented in this article are related to the research article entitled “Genome-wide transcriptomics analysis identifies sox7 and sox18 as specifically regulated by gata4 in cardiomyogenesis” (Afouda et al., 2017) [1]. The present study identifies genes regulated by these individual cardiogenic GATA factors using genome-wide transcriptomics analysis. We have presented genes that are specifically regulated by each of them, as well those regulated by either of them. The gene ontology terms (GO) associated with the genes differentially affected are also presented. The data set will allow further investigations on the gene regulatory network downstream of individual cardiogenic GATA factors during cardiac muscle formation.
Collapse
Affiliation(s)
- Boni A Afouda
- Institute of Medical Sciences, Foresterhill Health Campus, University of Aberdeen, Scotland, UK
| | - Adam T Lynch
- Institute of Medical Sciences, Foresterhill Health Campus, University of Aberdeen, Scotland, UK
| | - Eduardo de Paiva Alves
- Centre for Genome-Enabled Biology and Medicine, King's College Campus, University of Aberdeen, Scotland, UK
| | - Stefan Hoppler
- Institute of Medical Sciences, Foresterhill Health Campus, University of Aberdeen, Scotland, UK
| |
Collapse
|
6
|
Afouda BA, Lynch AT, de Paiva Alves E, Hoppler S. Genome-wide transcriptomics analysis identifies sox7 and sox18 as specifically regulated by gata4 in cardiomyogenesis. Dev Biol 2017; 434:108-120. [PMID: 29229250 PMCID: PMC5814753 DOI: 10.1016/j.ydbio.2017.11.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 11/29/2017] [Accepted: 11/29/2017] [Indexed: 01/12/2023]
Abstract
The transcription factors GATA4, GATA5 and GATA6 are important regulators of heart muscle differentiation (cardiomyogenesis), which function in a partially redundant manner. We identified genes specifically regulated by individual cardiogenic GATA factors in a genome-wide transcriptomics analysis. The genes regulated by gata4 are particularly interesting because GATA4 is able to induce differentiation of beating cardiomyocytes in Xenopus and in mammalian systems. Among the specifically gata4-regulated transcripts we identified two SoxF family members, sox7 and sox18. Experimental reinstatement of gata4 restores sox7 and sox18 expression, and loss of cardiomyocyte differentiation due to gata4 knockdown is partially restored by reinstating sox7 or sox18 expression, while (as previously reported) knockdown of sox7 or sox18 interferes with heart muscle formation. In order to test for conservation in mammalian cardiomyogenesis, we confirmed in mouse embryonic stem cells (ESCs) undergoing cardiomyogenesis that knockdown of Gata4 leads to reduced Sox7 (and Sox18) expression and that Gata4 is also uniquely capable of promptly inducing Sox7 expression. Taken together, we identify an important and conserved gene regulatory axis from gata4 to the SoxF paralogs sox7 and sox18 and further to heart muscle cell differentiation. Gata 4, 5 and 6 have redundant and non-redundant functions in heart development. RNA-seq analysis of Gata4, 5 and 6 knockdown experiments was carried out. Genes specifically regulated by Gata4, 5 and 6 were identified. The SoxF genes sox7 and sox18 were identified as specifically regulated by Gata4. Epistasis demonstrates a regulatory axis from Gata4 to Sox7/18 to cardiomyogenesis.
Collapse
Affiliation(s)
- Boni A Afouda
- Institute of Medical Sciences, Foresterhill Health Campus, University of Aberdeen, Scotland, UK
| | - Adam T Lynch
- Institute of Medical Sciences, Foresterhill Health Campus, University of Aberdeen, Scotland, UK
| | - Eduardo de Paiva Alves
- Centre for Genome-Enabled Biology and Medicine, King's College Campus, University of Aberdeen, Scotland, UK
| | - Stefan Hoppler
- Institute of Medical Sciences, Foresterhill Health Campus, University of Aberdeen, Scotland, UK.
| |
Collapse
|
7
|
Fisher JB, Pulakanti K, Rao S, Duncan SA. GATA6 is essential for endoderm formation from human pluripotent stem cells. Biol Open 2017; 6:1084-1095. [PMID: 28606935 PMCID: PMC5550920 DOI: 10.1242/bio.026120] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Protocols have been established that direct differentiation of human pluripotent stem cells into a variety of cell types, including the endoderm and its derivatives. This model of differentiation has been useful for investigating the molecular mechanisms that guide human developmental processes. Using a directed differentiation protocol combined with shRNA depletion we sought to understand the role of GATA6 in regulating the earliest switch from pluripotency to definitive endoderm. We reveal that GATA6 depletion during endoderm formation results in apoptosis of nascent endoderm cells, concomitant with a loss of endoderm gene expression. We show by chromatin immunoprecipitation followed by DNA sequencing that GATA6 directly binds to several genes encoding transcription factors that are necessary for endoderm differentiation. Our data support the view that GATA6 is a central regulator of the formation of human definitive endoderm from pluripotent stem cells by directly controlling endoderm gene expression. Summary: Using the differentiation of huESCs as a model for endoderm formation, we reveal that the transcription factor GATA6 regulates the onset of endoderm gene expression and is required for its viability.
Collapse
Affiliation(s)
- J B Fisher
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA.,Blood Center of Wisconsin, Milwaukee, WI 53226, USA
| | - K Pulakanti
- Blood Center of Wisconsin, Milwaukee, WI 53226, USA
| | - S Rao
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA.,Blood Center of Wisconsin, Milwaukee, WI 53226, USA.,Division of Pediatric Hematology, Oncology, and Blood and Marrow Transplant, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - S A Duncan
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA .,Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC 29425, USA
| |
Collapse
|
8
|
Charney RM, Paraiso KD, Blitz IL, Cho KWY. A gene regulatory program controlling early Xenopus mesendoderm formation: Network conservation and motifs. Semin Cell Dev Biol 2017; 66:12-24. [PMID: 28341363 DOI: 10.1016/j.semcdb.2017.03.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 03/12/2017] [Accepted: 03/20/2017] [Indexed: 02/08/2023]
Abstract
Germ layer formation is among the earliest differentiation events in metazoan embryos. In triploblasts, three germ layers are formed, among which the endoderm gives rise to the epithelial lining of the gut tube and associated organs including the liver, pancreas and lungs. In frogs (Xenopus), where early germ layer formation has been studied extensively, the process of endoderm specification involves the interplay of dozens of transcription factors. Here, we review the interactions between these factors, summarized in a transcriptional gene regulatory network (GRN). We highlight regulatory connections conserved between frog, fish, mouse, and human endodermal lineages. Especially prominent is the conserved role and regulatory targets of the Nodal signaling pathway and the T-box transcription factors, Vegt and Eomes. Additionally, we highlight network topologies and motifs, and speculate on their possible roles in development.
Collapse
Affiliation(s)
- Rebekah M Charney
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, CA 92697, USA
| | - Kitt D Paraiso
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, CA 92697, USA
| | - Ira L Blitz
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, CA 92697, USA
| | - Ken W Y Cho
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, CA 92697, USA.
| |
Collapse
|
9
|
Kiecker C, Bates T, Bell E. Molecular specification of germ layers in vertebrate embryos. Cell Mol Life Sci 2016; 73:923-47. [PMID: 26667903 PMCID: PMC4744249 DOI: 10.1007/s00018-015-2092-y] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 10/11/2015] [Accepted: 11/09/2015] [Indexed: 11/17/2022]
Abstract
In order to generate the tissues and organs of a multicellular organism, different cell types have to be generated during embryonic development. The first step in this process of cellular diversification is the formation of the three germ layers: ectoderm, endoderm and mesoderm. The ectoderm gives rise to the nervous system, epidermis and various neural crest-derived tissues, the endoderm goes on to form the gastrointestinal, respiratory and urinary systems as well as many endocrine glands, and the mesoderm will form the notochord, axial skeleton, cartilage, connective tissue, trunk muscles, kidneys and blood. Classic experiments in amphibian embryos revealed the tissue interactions involved in germ layer formation and provided the groundwork for the identification of secreted and intracellular factors involved in this process. We will begin this review by summarising the key findings of those studies. We will then evaluate them in the light of more recent genetic studies that helped clarify which of the previously identified factors are required for germ layer formation in vivo, and to what extent the mechanisms identified in amphibians are conserved across other vertebrate species. Collectively, these studies have started to reveal the gene regulatory network (GRN) underlying vertebrate germ layer specification and we will conclude our review by providing examples how our understanding of this GRN can be employed to differentiate stem cells in a targeted fashion for therapeutic purposes.
Collapse
Affiliation(s)
- Clemens Kiecker
- MRC Centre for Developmental Neurobiology, King's College London, Guy's Campus, London, UK
| | - Thomas Bates
- MRC Centre for Developmental Neurobiology, King's College London, Guy's Campus, London, UK
- Leibniz Institute on Aging, Fritz Lipmann Institute, Jena, Germany
| | - Esther Bell
- MRC Centre for Developmental Neurobiology, King's College London, Guy's Campus, London, UK.
| |
Collapse
|
10
|
Kofent J, Spagnoli FM. Xenopus as a model system for studying pancreatic development and diabetes. Semin Cell Dev Biol 2016; 51:106-16. [PMID: 26806634 DOI: 10.1016/j.semcdb.2016.01.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 01/06/2016] [Indexed: 02/07/2023]
Abstract
Diabetes is a chronic disease caused by the loss or dysfunction of the insulin-producing β-cells in the pancreas. To date, much of our knowledge about β-cells in humans comes from studying rare monogenic forms of diabetes. Importantly, the majority of mutations so far associated to monogenic diabetes are in genes that exert a regulatory role in pancreatic development and/or β-cell function. Thus, the identification and study of novel mutations open an unprecedented window into human pancreatic development. In this review, we summarize major advances in the genetic dissection of different types of monogenic diabetes and the insights gained from a developmental perspective. We highlight future challenges to bridge the gap between the fast accumulation of genetic data through next-generation sequencing and the need of functional insights into disease mechanisms. Lastly, we discuss the relevance and advantages of studying candidate gene variants in vivo using the Xenopus as model system.
Collapse
Affiliation(s)
- Julia Kofent
- Max Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Str. 10, D-13125 Berlin, Germany
| | - Francesca M Spagnoli
- Max Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Str. 10, D-13125 Berlin, Germany.
| |
Collapse
|
11
|
Caporilli S, Latinkic BV. Ventricular cell fate can be specified until the onset of myocardial differentiation. Mech Dev 2016; 139:31-41. [PMID: 26776863 PMCID: PMC4798847 DOI: 10.1016/j.mod.2016.01.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 12/24/2015] [Accepted: 01/07/2016] [Indexed: 02/03/2023]
Abstract
The mechanisms that govern specification of various cell types that constitute vertebrate heart are not fully understood. Whilst most studies of heart development have utilised the mouse embryo, we have used an alternative model, embryos of the frog Xenopus laevis, which permits direct experimental manipulation of a non-essential heart. We show that in this model pluripotent animal cap explants injected with cardiogenic factor GATA4 mRNA express pan-myocardial as well as ventricular and proepicardial markers. We found that cardiac cell fate diversification, as assessed by ventricular and proepicardial markers, critically depends on tissue integrity, as it is disrupted by dissociation but can be fully restored by inhibition of the BMP pathway and partially by Dkk-1. Ventricular and proepicardial cell fates can also be restored in reaggregated GATA4-expressing cells upon transplantation into a host embryo. The competence of the host embryo to induce ventricular and proepicardial markers gradually decreases with the age of the transplant and is lost by the onset of myocardial differentiation at the late tailbud stage (st. 28). The influence of the host on the transplant was not limited to diversification of cardiac cell fates, but also included induction of growth and rhythmic beating, resulting in generation of a secondary heart-like structure. Our results additionally show that efficient generation of secondary heart requires normal axial patterning of the host embryo. Furthermore, secondary hearts can be induced in a wide range of locations within the host, arguing that the host embryo provides a permissive environment for development of cardiac patterning, growth and physiological maturation. Our results have implications for a major goal of cardiac regenerative medicine, differentiation of ventricular myocardium. Ventricular and proepicardial fate can be induced by cardiogenic factor GATA4. This process requires tissue integrity. Ventricular and proepicardial cell fate can be restored by BMP inhibition. A secondary heart-like structure can be induced from GATA4-expressing cells.
Collapse
Affiliation(s)
- Simona Caporilli
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, Wales, UK
| | - Branko V Latinkic
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, Wales, UK.
| |
Collapse
|
12
|
Aronson BE, Stapleton KA, Krasinski SD. Role of GATA factors in development, differentiation, and homeostasis of the small intestinal epithelium. Am J Physiol Gastrointest Liver Physiol 2014; 306:G474-90. [PMID: 24436352 PMCID: PMC3949026 DOI: 10.1152/ajpgi.00119.2013] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The small intestinal epithelium develops from embryonic endoderm into a highly specialized layer of cells perfectly suited for the digestion and absorption of nutrients. The development, differentiation, and regeneration of the small intestinal epithelium require complex gene regulatory networks involving multiple context-specific transcription factors. The evolutionarily conserved GATA family of transcription factors, well known for its role in hematopoiesis, is essential for the development of endoderm during embryogenesis and the renewal of the differentiated epithelium in the mature gut. We review the role of GATA factors in the evolution and development of endoderm and summarize our current understanding of the function of GATA factors in the mature small intestine. We offer perspective on the application of epigenetics approaches to define the mechanisms underlying context-specific GATA gene regulation during intestinal development.
Collapse
Affiliation(s)
- Boaz E. Aronson
- 1Division of Gastroenterology and Nutrition, Department of Medicine, Children's Hospital Boston, and Harvard Medical School, Boston, Massachusetts; ,2Department of Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; and
| | - Kelly A. Stapleton
- 1Division of Gastroenterology and Nutrition, Department of Medicine, Children's Hospital Boston, and Harvard Medical School, Boston, Massachusetts;
| | - Stephen D. Krasinski
- 1Division of Gastroenterology and Nutrition, Department of Medicine, Children's Hospital Boston, and Harvard Medical School, Boston, Massachusetts; ,3Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachusetts
| |
Collapse
|
13
|
Ciau-Uitz A, Pinheiro P, Kirmizitas A, Zuo J, Patient R. VEGFA-dependent and -independent pathways synergise to drive Scl expression and initiate programming of the blood stem cell lineage in Xenopus. Development 2013; 140:2632-42. [PMID: 23637333 PMCID: PMC3666388 DOI: 10.1242/dev.090829] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/03/2013] [Indexed: 01/23/2023]
Abstract
The first haematopoietic stem cells share a common origin with the dorsal aorta and derive from putative adult haemangioblasts in the dorsal lateral plate (DLP) mesoderm. Here we show that the transcription factor (TF) stem cell leukaemia (Scl/Tal1) is crucial for development of these adult haemangioblasts in Xenopus and establish the regulatory cascade controlling its expression. We show that VEGFA produced in the somites is required to initiate adult haemangioblast programming in the adjacent DLP by establishing endogenous VEGFA signalling. This response depends on expression of the VEGF receptor Flk1, driven by Fli1 and Gata2. Scl activation requires synergy between this VEGFA-controlled pathway and a VEGFA-independent pathway controlled by Fli1, Gata2 and Etv2/Etsrp/ER71, which also drives expression of the Scl partner Lmo2. Thus, the two ETS factors Fli1 and Etv6, which drives the VEGFA expression in both somites and the DLP, sit at the top of the adult haemangioblast gene regulatory network (GRN). Furthermore, Gata2 is initially activated by Fli1 but later maintained by another ETS factor, Etv2. We also establish that Flk1 and Etv2 act independently in the two pathways to Scl activation. Thus, detailed temporal, epistatic measurements of key TFs and VEGFA plus its receptor have enabled us to build a Xenopus adult haemangioblast GRN.
Collapse
Affiliation(s)
- Aldo Ciau-Uitz
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DS, UK
| | - Philip Pinheiro
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DS, UK
| | - Arif Kirmizitas
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DS, UK
| | - Jie Zuo
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DS, UK
| | - Roger Patient
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DS, UK
| |
Collapse
|
14
|
Serrano F, Calatayud CF, Blazquez M, Torres J, Castell JV, Bort R. Gata4 Blocks Somatic Cell Reprogramming By Directly Repressing Nanog. Stem Cells 2012; 31:71-82. [DOI: 10.1002/stem.1272] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Accepted: 10/04/2012] [Indexed: 12/31/2022]
|
15
|
Liu C, Goswami M, Talley J, Chesser-Martinez PL, Lou CH, Sater AK. TAK1 promotes BMP4/Smad1 signaling via inhibition of erk MAPK: a new link in the FGF/BMP regulatory network. Differentiation 2012; 83:210-9. [PMID: 22387344 DOI: 10.1016/j.diff.2011.12.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 12/05/2011] [Accepted: 12/31/2011] [Indexed: 01/22/2023]
Abstract
FGFs and BMPs act in concert to regulate a wide range of processes in vertebrate development. In most cases, FGFs and BMPs have opposing effects, and specific developmental outcomes arise out of a balance between the two growth factors. We and others have previously demonstrated that signaling pathways activated by FGFs and BMPs interact via inhibitory crosstalk. Here we demonstrate a role for the BMP effector TGF-β Activated Kinase 1 (TAK1) in the maintenance of Smad1 activity in Xenopus embryos, via the inhibition of erk MAPK. Up- or downregulation of TAK1 levels produces an inverse alteration in the amount of activated erk MAPK. The inhibition of erk MAPK by TAK1 is mediated by p38 and a corresponding decrease in phosphorylation of MEK. TAK1 morphant embryos show a decrease in the nuclear accumulation of Smad1. Conversely, reduction of erk MAPK activity via overexpression of MAP Kinase Phosphatase1 (MKP1) leads to an increase in nuclear Smad1. Both TAK1 morphant ectoderm and ectoderm treated with FGF show a decrease in the expression of several Smad1-inducible genes. Neural-specific gene expression is inhibited in isolated ectoderm coexpressing noggin and TAK1, suggesting that TAK1 is sufficient to inhibit neural specification. Introduction of TAK1 morpholino oligonucleotide expands the expression of organizer genes, disrupts formation of the boundary between organizer and non-organizer mesoderm, and increases the spatial range of MAPK activation in response to localized FGF. Our results indicate that inhibitory interactions between FGF and BMP4 effector pathways increase the robustness of BMP signaling via a feed-forward mechanism.
Collapse
Affiliation(s)
- Chen Liu
- Department of Biology and Biochemistry, University of Houston, Houston, TX 77204-5001, USA
| | | | | | | | | | | |
Collapse
|
16
|
Abstract
Cells from the animal pole of Xenopus blastula embryo possess pluripotency that can be used to generate various tissues and even functional organs ex vivo. This finding has sparkled development of a variety of experimental protocols to study mechanisms that underlie formation of various organs and explore strategies for organ engineering for clinical applications. In this chapter, key methods are described for using Xenopus stem-cell-like embryonic explants as an assay system for studying organ development, with a focus on cardiogenesis. This assay allows investigation of cardiogenesis in isolation from neighboring tissues, minimizes interference with other developmental processes, and presents the further advantage of a heterologous system to study cardiogenesis in isolation of endogenous development of the heart. The cardiogenic assays can be exploited to investigate molecular mechanisms and cellular processes that underlie function of different molecules involved in cardiogenesis.
Collapse
Affiliation(s)
- Boni A Afouda
- Institute of Medical Sciences, University of Aberdeen, Scotland, UK.
| |
Collapse
|
17
|
Taubenschmid J, Weitzer G. Mechanisms of cardiogenesis in cardiovascular progenitor cells. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2012; 293:195-267. [PMID: 22251563 PMCID: PMC7615846 DOI: 10.1016/b978-0-12-394304-0.00012-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Self-renewing cells of the vertebrate heart have become a major subject of interest in the past decade. However, many researchers had a hard time to argue against the orthodox textbook view that defines the heart as a postmitotic organ. Once the scientific community agreed on the existence of self-renewing cells in the vertebrate heart, their origin was again put on trial when transdifferentiation, dedifferentiation, and reprogramming could no longer be excluded as potential sources of self-renewal in the adult organ. Additionally, the presence of self-renewing pluripotent cells in the peripheral blood challenges the concept of tissue-specific stem and progenitor cells. Leaving these unsolved problems aside, it seems very desirable to learn about the basic biology of this unique cell type. Thus, we shall here paint a picture of cardiovascular progenitor cells including the current knowledge about their origin, basic nature, and the molecular mechanisms guiding proliferation and differentiation into somatic cells of the heart.
Collapse
Affiliation(s)
- Jasmin Taubenschmid
- Max F. Perutz Laboratories, Department of Medical Biochemistry, Medical University of Vienna, Vienna, Austria
| | | |
Collapse
|
18
|
Chen H, Fang Y, Tevebaugh W, Orlando RC, Shaheen NJ, Chen X. Molecular mechanisms of Barrett's esophagus. Dig Dis Sci 2011; 56:3405-20. [PMID: 21984436 PMCID: PMC3750118 DOI: 10.1007/s10620-011-1885-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Accepted: 08/16/2011] [Indexed: 12/11/2022]
Abstract
Barrett's esophagus (BE) is defined as the metaplastic conversion of esophageal squamous epithelium to intestinalized columnar epithelium. As a premalignant lesion of esophageal adenocarcinoma (EAC), BE develops as a result of chronic gastroesophageal reflux disease (GERD). Many studies have been conducted to understand the molecular mechanisms of this disease. This review summarizes recent results involving squamous and intestinal transcription factors, signaling pathways, stromal factors, microRNAs, and other factors in the development of BE. A conceptual framework is proposed to guide future studies. We expect elucidation of the molecular mechanisms of BE to help in the development of improved management of GERD, BE, and EAC.
Collapse
Affiliation(s)
- Hao Chen
- Cancer Research Program, JLC-BBRI, North Carolina Central University, Durham, NC 27707, USA
| | - Yu Fang
- Cancer Research Program, JLC-BBRI, North Carolina Central University, Durham, NC 27707, USA
| | - Whitney Tevebaugh
- Cancer Research Program, JLC-BBRI, North Carolina Central University, Durham, NC 27707, USA
| | - Roy C. Orlando
- Center for Esophageal Diseases and Swallowing, University of North Carolina School of Medicine, Chapel Hill, NC 27599-7080, USA
| | - Nicholas J. Shaheen
- Center for Esophageal Diseases and Swallowing, University of North Carolina School of Medicine, Chapel Hill, NC 27599-7080, USA
| | - Xiaoxin Chen
- Cancer Research Program, JLC-BBRI, North Carolina Central University, Durham, NC 27707, USA,Center for Esophageal Diseases and Swallowing, University of North Carolina School of Medicine, Chapel Hill, NC 27599-7080, USA,Corresponding authors: Xiaoxin Luke Chen, MD, PhD, Cancer Research Program, Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, 700 George Street, Durham, NC 27707, USA. Tel: 919-530-6425; Fax: 919-530-7780;
| |
Collapse
|
19
|
Schuff M, Siegel D, Philipp M, Bundschu K, Heymann N, Donow C, Knöchel W. Characterization of Danio rerio Nanog and functional comparison to Xenopus Vents. Stem Cells Dev 2011; 21:1225-38. [PMID: 21967637 DOI: 10.1089/scd.2011.0285] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Nanog is a homeodomain transcription factor associated with the acquisition of pluripotency. Genome analyses of lower and higher vertebrates revealed that the existence of Nanog is restricted to gnathostomata but absent from agnatha and invertebrates. To elucidate the function of Nanog in nonmammalia, we identified the Danio rerio ortholog of Nanog and characterized its role in gain and loss of function experiments. We found Nanog to be crucial for survival of early zebrafish embryos, because depletion of Nanog led to gastrulation defects with subsequent lethality. Mouse Nanog overexpression could rescue these defects. Vice versa, zebrafish Nanog was found to promote proliferation and to inhibit differentiation of mouse embryonic stem cells in the absence of leukemia inhibitory factor. These findings indicate functional conservation of Nanog from teleost fishes to mammals. However, Nanog was lost in the genome of the anurans Xenopus laevis and Xenopus tropicalis. Phylogenetic analysis revealed that deletion probably occurred in a common anuran ancestor along with chromosomal translocations. The closest homologs of Nanog in Xenopus are the Vent proteins. We, therefore, investigated whether the Xvent genes might substitute for Nanog function in Xenopus. Although we found some similarities in phenotypes after overexpression and in the regulation of several marker genes, Xvent1/2 and Nanog cannot substitute each other. Depletion of Nanog in zebrafish cannot be rescued by ectopic expression of Xvent, and Xvent depletion in Xenopus cannot be overcome by ectopic expression of zebrafish Nanog.
Collapse
|
20
|
Dynamic chromatin states in human ES cells reveal potential regulatory sequences and genes involved in pluripotency. Cell Res 2011; 21:1393-409. [PMID: 21876557 DOI: 10.1038/cr.2011.146] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Pluripotency, the ability of a cell to differentiate and give rise to all embryonic lineages, defines a small number of mammalian cell types such as embryonic stem (ES) cells. While it has been generally held that pluripotency is the product of a transcriptional regulatory network that activates and maintains the expression of key stem cell genes, accumulating evidence is pointing to a critical role for epigenetic processes in establishing and safeguarding the pluripotency of ES cells, as well as maintaining the identity of differentiated cell types. In order to better understand the role of epigenetic mechanisms in pluripotency, we have examined the dynamics of chromatin modifications genome-wide in human ES cells (hESCs) undergoing differentiation into a mesendodermal lineage. We found that chromatin modifications at promoters remain largely invariant during differentiation, except at a small number of promoters where a dynamic switch between acetylation and methylation at H3K27 marks the transition between activation and silencing of gene expression, suggesting a hierarchy in cell fate commitment over most differentially expressed genes. We also mapped over 50 000 potential enhancers, and observed much greater dynamics in chromatin modifications, especially H3K4me1 and H3K27ac, which correlate with expression of their potential target genes. Further analysis of these enhancers revealed potentially key transcriptional regulators of pluripotency and a chromatin signature indicative of a poised state that may confer developmental competence in hESCs. Our results provide new evidence supporting the role of chromatin modifications in defining enhancers and pluripotency.
Collapse
|
21
|
Tseng WF, Jang TH, Huang CB, Yuh CH. An evolutionarily conserved kernel of gata5, gata6, otx2 and prdm1a operates in the formation of endoderm in zebrafish. Dev Biol 2011; 357:541-57. [PMID: 21756893 DOI: 10.1016/j.ydbio.2011.06.040] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 06/09/2011] [Accepted: 06/23/2011] [Indexed: 10/18/2022]
Abstract
An evolutionarily conserved subcircuit (kernel) dedicated to a specific developmental function is found at the top of the gene regulatory networks (GRNs) hierarchy. Here we comprehensively demonstrate that a pan-deuterostome endoderm specification kernel exists in zebrafish. We analyzed interactions among gata5, gata6, otx2 and prdm1a using specific morpholino knockdowns and measured the gene expression profiles by quantitative real-time RT-PCR and in situ hybridization. The mRNA rescue experiment validated the specificity of the morpholino knockdown. We found that the interactions among gata5, gata6, otx2 and prdm1a determine the initial specification of the zebrafish endoderm. Although otx2 can activate both gata5 and gata6, and the prdm1a/krox homologue also activates some endoderm transcription factors, a feedback loop from Gata to otx2 and prdm1a is missing. Furthermore, we found the positive regulation between gata5 and gata6 to further lock-on the mesendoderm specification by the Gata family. Chromatin immunoprecipitation was used to further validate the recruitment of Otx2 to the gata5 and gata6 loci. Functional assays revealed that module B of gata6 and the basal promoter of gata5 drive the gene at the mesendoderm, and mutational analysis demonstrated that Otx2 and Gata5/6 contribute to reporter gene activation. This is the first direct evidence for evolutionarily conserved endoderm specification across echinoderms and vertebrates.
Collapse
Affiliation(s)
- Wen-Fang Tseng
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Zhunan Town, Miaoli County 350, Taiwan, ROC
| | | | | | | |
Collapse
|
22
|
Pan Y, Ouyang Z, Wong WH, Baker JC. A new FACS approach isolates hESC derived endoderm using transcription factors. PLoS One 2011; 6:e17536. [PMID: 21408072 PMCID: PMC3052315 DOI: 10.1371/journal.pone.0017536] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Accepted: 02/08/2011] [Indexed: 01/18/2023] Open
Abstract
We show that high quality microarray gene expression profiles can be obtained following FACS sorting of cells using combinations of transcription factors. We use this transcription factor FACS (tfFACS) methodology to perform a genomic analysis of hESC-derived endodermal lineages marked by combinations of SOX17, GATA4, and CXCR4, and find that triple positive cells have a much stronger definitive endoderm signature than other combinations of these markers. Additionally, SOX17(+) GATA4(+) cells can be obtained at a much earlier stage of differentiation, prior to expression of CXCR4(+) cells, providing an important new tool to isolate this earlier definitive endoderm subtype. Overall, tfFACS represents an advancement in FACS technology which broadly crosses multiple disciplines, most notably in regenerative medicine to redefine cellular populations.
Collapse
Affiliation(s)
- Yuqiong Pan
- Departments of Statistics, Genetics, and Developmental Biology, Stanford University, Stanford, California, United States of America
| | - Zhengqing Ouyang
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Wing Hung Wong
- Departments of Statistics, Health Research and Policy, and Biology, Stanford University, Stanford, California, United States of America
- * E-mail: (WHW); (JCB)
| | - Julie C. Baker
- Department of Genetics, Stanford University, Stanford, California, United States of America
- * E-mail: (WHW); (JCB)
| |
Collapse
|
23
|
Afouda BA, Hoppler S. Different requirements for GATA factors in cardiogenesis are mediated by non-canonical Wnt signaling. Dev Dyn 2011; 240:649-62. [DOI: 10.1002/dvdy.22570] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/30/2010] [Indexed: 01/21/2023] Open
|
24
|
Wen L, Yang Y, Wang Y, Xu A, Wu D, Chen Y. Appl1 is essential for the survival of Xenopus pancreas, duodenum, and stomach progenitor cells. Dev Dyn 2010; 239:2198-207. [PMID: 20568240 DOI: 10.1002/dvdy.22356] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
An understanding of the molecular mechanisms governing the survival of organ progenitor cells in vivo is crucial for in vitro tissue regeneration. Here, we have found that Xenopus appl1 and akt2 share a similar embryonic expression pattern, showing characteristic expression in the central nervous system as well as in the pancreas and part of the stomach/duodenum (SD) at tadpole stages of development. Specific knockdown of appl1 in endoderm or inhibition of akt activity did not affect the formation of endodermal organ primordia at tail bud stages of development, but led to a gut-coiling defect, strong apoptosis in endodermal organs, and pancreas and SD hypoplasia or even aplasia at tadpole stages of development. Furthermore, appl1 is required for akt phosphorylation and akt2 in turn can rescue appl1 knockdown phenotypes. Together, our data suggest that appl1-akt signaling is specifically required for the survival of pancreas and SD progenitor cells in Xenopus laevis embryos.
Collapse
Affiliation(s)
- Luan Wen
- Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, 510663 Guangzhou, China
| | | | | | | | | | | |
Collapse
|
25
|
Abstract
Abstract The establishment of efficient methods for promoting stem cell differentiation into target cells is important not only in regenerative medicine, but also in drug discovery. In addition to embryonic stem (ES) cells and various somatic stem cells, such as mesenchymal stem cells derived from bone marrow, adipose tissue, and umbilical cord blood, a novel dedifferentiation technology that allows the generation of induced pluripotent stem (iPS) cells has been recently developed. Although an increasing number of stem cell populations are being described, there remains a lack of protocols for driving the differentiation of these cells. Regeneration of organs from stem cells in vitro requires precise blueprints for each differentiation step. To date, studies using various model organisms, such as zebrafish, Xenopus laevis, and gene-targeted mice, have uncovered several factors that are critical for the development of organs. We have been using X. laevis, the African clawed frog, which has developmental patterns similar to those seen in humans. Moreover, Xenopus embryos are excellent research tools for the development of differentiation protocols, since they are available in high numbers and are sufficiently large and robust for culturing after simple microsurgery. In addition, Xenopus eggs are fertilized externally, and all stages of the embryo are easily accessible, making it relatively easy to study the functions of individual gene products during organogenesis using microinjection into embryonic cells. In the present review, we provide examples of methods for in vitro organ formation that use undifferentiated Xenopus cells. We also describe the application of amphibian differentiation protocols to mammalian stem cells, so as to facilitate the development of efficient methodologies for in vitro differentiation.
Collapse
Affiliation(s)
- Akira Kurisaki
- Organ Development Research Laboratory, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan
| | | | | | | | | |
Collapse
|
26
|
Abstract
OBJECTIVES To identify gene expression alterations associated with insulinoma formation and progression in 2 mouse models of multiple endocrine neoplasia type 1. METHODS Mice were killed at 12 or 16 months, and pancreatic islets were isolated by enzymatic and physical disruption. Islets were separated by size representing control, normal, hyperplastic, and adenomous islets. RNA was isolated from these islets and profiled on Sentrix Mouse-6 Expression version 1 BeadChips. Array data were analyzed in GeneSpring. RESULTS One hundred and one genes that were significantly (P ≤ 0.05) altered in hyperplastic islets and insulinomas compared with normal islets were identified. Of these, 64 gene elements showed reduced messenger RNA levels and 37 gene elements had increased gene expression compared with control islets. Altered expression of 3 genes, namely, Gata6, Tspan8, and s100a8, was confirmed by quantitative reverse transcription-polymerase chain reaction, and aberrant levels of Tspan8 and Lmo2 protein measured by Western blot correlated with the changes in messenger RNA levels. CONCLUSIONS These results suggest that alterations in gene expression of Gata6, Tspan8, S100a8, and Lmo2 may act via novel pathways that play functionally important roles in Men1-associated tumor progression.
Collapse
|
27
|
Martin J, Afouda BA, Hoppler S. Wnt/beta-catenin signalling regulates cardiomyogenesis via GATA transcription factors. J Anat 2010; 216:92-107. [PMID: 20402826 DOI: 10.1111/j.1469-7580.2009.01171.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
A functioning heart muscle is required continuously throughout life. During embryonic development the heart muscle tissue differentiates from mesoderm that has heart-forming potential. Heart-forming potential in the embryonic mesoderm is regulated by pro-cardiogenic transcription factors, such as members of the GATA and NK-2 transcription factor families. Subsequent heart muscle differentiation involves the expression of cytoskeletal proteins, including myosins and troponins. Different Wnt signalling pathways have various functions in heart development. So-called 'canonical' (Wnt/beta-catenin-mediated) signalling has a conserved role in vertebrate heart development, regulating and restricting heart development and subsequent heart muscle differentiation. Here we investigated the way in which Wnt/beta-catenin signalling functionally interacts with the GATA family of pro-cardiogenic transcription factors to regulate subsequent heart muscle differentiation. We used whole Xenopus embryos as an accessible experimental model system for vertebrate heart development. Our experiments confirmed that activation of Wnt signalling results in reduced gata gene expression, as well as reduced gene expression of other pro-cardiogenic transcription factors and heart muscle differentiation markers. Remarkably, we discovered that when GATA function is experimentally restored, the expression of other pro-cardiogenic transcription factors and heart muscle differentiation markers is rescued. These findings, obtained from whole-embryo experiments, show that Wnt signalling regulates heart development at the level of GATA factors, confirming earlier results from tissue-culture experiments. Furthermore, our rescue experiments in Xenopus embryos revealed differences in functional activity between the various GATA transcription factors involved in heart development. We discovered that GATA4 is more efficient at reinstating the gene expression of other pro-cardiogenic transcription factors, whereas GATA6 is more potent at promoting the expression of genes associated with terminal heart muscle differentiation. In conclusion, our findings show that the inhibition of heart development by Wnt/beta-catenin signalling during organogenesis is mediated by the loss of expression of GATA pro-cardiogenic transcription factors and reveal functional differences between those GATA factors in heart development.
Collapse
Affiliation(s)
- Jennifer Martin
- Cell and Developmental Biology Research Programme, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, UK
| | | | | |
Collapse
|
28
|
Abstract
Many developmental processes are highly conserved in all vertebrate organisms. This conservation has allowed developmental biologists to use numerous animal models to further our understanding of the molecular mechanisms that govern heart development and congenital heart disease. Amphibian embryos represent a useful model for such studies because their relatively large embryos are available in large numbers and survive simple microsurgery. In addition, until swimming tadpole stages, an amphibian embryo develops using nutrients stored in each of its many cells. This feature has the advantage that explants isolated from embryonic tissue will continue to survive in isolation and differentiate in culture. Furthermore, cells from the ectodermal layer of the blastula or gastrula embryos are stem cell like in that they are pluripotent and can be induced to form various tissues in vitro. Here, we will review work from recent studies in which explants from the amphibian embryos were used to further our understanding of vertebrate heart development. We will bring together the key facts needed for using Xenopus explants as experimental approaches for studying molecular pathways and gene regulatory networks in vertebrate cardiogenesis. The knowledge generated with these approaches supports the usefulness of amphibian explants, and the relevance of the findings strongly validates the conservation of molecular pathways that underlie heart development in all vertebrates.
Collapse
|
29
|
Rojas A, Schachterle W, Xu SM, Black BL. An endoderm-specific transcriptional enhancer from the mouse Gata4 gene requires GATA and homeodomain protein-binding sites for function in vivo. Dev Dyn 2010; 238:2588-98. [PMID: 19777593 DOI: 10.1002/dvdy.22091] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Several transcription factors function in the specification and differentiation of the endoderm, including the zinc finger transcription factor GATA4. Despite its essential role in endoderm development, the transcriptional control of the Gata4 gene in the developing endoderm and its derivatives remains incompletely understood. Here, we identify a distal enhancer from the Gata4 gene, which directs expression exclusively to the visceral and definitive endoderm of transgenic mouse embryos. The activity of this enhancer is initially broad within the definitive endoderm but later restricts to developing endoderm-derived tissues, including pancreas, glandular stomach, and duodenum. The activity of this enhancer in vivo is dependent on evolutionarily-conserved HOX- and GATA-binding sites, which are bound by PDX-1 and GATA4, respectively. These studies establish Gata4 as a direct transcriptional target of homeodomain and GATA transcription factors in the endoderm and support a model in which GATA4 functions in the transcriptional network for pancreas formation.
Collapse
Affiliation(s)
- Anabel Rojas
- Cardiovascular Research Institute, University of California, San Francisco, California, USA
| | | | | | | |
Collapse
|
30
|
Stk40 links the pluripotency factor Oct4 to the Erk/MAPK pathway and controls extraembryonic endoderm differentiation. Proc Natl Acad Sci U S A 2010; 107:1402-7. [PMID: 20080709 DOI: 10.1073/pnas.0905657107] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Self-renewal and differentiation of embryonic stem cells (ESCs) are controlled by intracellular transcriptional factors and extracellular factor-activated signaling pathways. Transcription factor Oct4 is a key player maintaining ESCs in an undifferentiated state, whereas the Erk/MAPK pathway is known to be important for ESC differentiation. However, the manner in which intracellular pluripotency factors modulate extracellular factor-activated signaling pathways in ESCs is not well understood. Here, we report identification of a target gene of Oct4, serine/threonine kinase 40 (Stk40), which is able to activate the Erk/MAPK pathway and induce extraembryonic-endoderm (ExEn) differentiation in mouse ESCs. Interestingly, cells overexpressing Stk40 exclusively contribute to the ExEn layer of chimeric embryos when injected into host blastocysts. In contrast, deletion of Stk40 in ESCs markedly reduces ExEn differentiation in vitro. Mechanistically, Stk40 interacts with Rcn2, which also activates Erk1/2 to induce ExEn specification in mouse ESCs. Moreover, Rcn2 proteins are specifically located in the cytoplasm of the ExEn layer of early mouse embryos. Importantly, knockdown of Rcn2 blocks Stk40-activated Erk1/2 and ESC differentiation. Therefore, our study establishes a link between the pluripotency factor Oct4 and the Erk/MAPK signaling pathway, and it uncovers cooperating signals in the Erk/MAPK activation that control ExEn differentiation.
Collapse
|
31
|
Tremblay KD. Formation of the murine endoderm: lessons from the mouse, frog, fish, and chick. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2010; 96:1-34. [PMID: 21075338 DOI: 10.1016/b978-0-12-381280-3.00001-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The mammalian definitive endoderm arises as a simple epithelial sheet. This sheet of cells will eventually produce the innermost tube that comprises the entire digestive tract from the esophagus to the colon as well as the epithelial component of the digestive and respiratory organs including the thymus, thyroid, lung, liver, gallbladder, and pancreas. Thus a wide array of tissue types are derived from the early endodermal sheet, and understanding the morphological and molecular mechanisms used to produce this tissue is integral to understanding the development of all these organs. The goal of this chapter is to summarize what is known about the morphological and molecular mechanisms used to produce this embryonic germ layer. Although this chapter mainly focuses on the mechanisms used to generate the murine endoderm, supportive or suggestive data from other species, including chick, frog (Xenopus laevis), and the Zebrafish (Danio rerio) are also examined.
Collapse
Affiliation(s)
- Kimberly D Tremblay
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, Massachusetts, USA
| |
Collapse
|
32
|
Holtzinger A, Rosenfeld GE, Evans T. Gata4 directs development of cardiac-inducing endoderm from ES cells. Dev Biol 2009; 337:63-73. [PMID: 19850025 DOI: 10.1016/j.ydbio.2009.10.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2009] [Revised: 10/05/2009] [Accepted: 10/06/2009] [Indexed: 01/06/2023]
Abstract
The transcription factor Gata4 is essential for normal heart morphogenesis and regulates the survival, growth, and proliferation of cardiomyocytes. We tested if Gata4 can specify cardiomyocyte fate from an uncommitted stem or progenitor cell population, by developing a system for conditional expression of Gata4 in embryonic stem cells. We find that in embryoid body cultures containing even a low ratio of these cells, expression of Gata4 is sufficient to enhance significantly the generation of cardiomyocytes, via a non-cell-autonomous mechanism. The Gata4-expressing cells do not generate cardiac or other mesoderm derivatives. Rather, Gata4 expression directs the development of two types of Sox17+ endoderm. This includes an epCam+Dpp4+ subtype of visceral endoderm. In addition, Gata4 generates similar amounts of epCam+Dpp4- definitive endoderm enriched for Cxcr4, FoxA2, FoxA3, Dlx5 and other characteristic transcripts. Both types of endoderm express cardiac-inducing factors, including WNT antagonists Dkk1 and Sfrp5, although the visceral endoderm subtype has much higher cardiac-inducing activity correlating with relatively enhanced levels of transcripts encoding BMPs. The Gata4-expressing cells eventually express differentiation markers showing commitment to liver development, even under conditions that normally support mesoderm development. The results suggest that Gata4 is capable of specifying endoderm fates that facilitate, with temporal and spatial specificity, the generation of cardiomyocyte progenitors from associated mesoderm.
Collapse
Affiliation(s)
- Audrey Holtzinger
- Department of Surgery, Weill Cornell Medical School, New York, NY 10021, USA
| | | | | |
Collapse
|
33
|
Kwek J, De Iongh R, Nicholas K, Familari M. Molecular insights into evolution of the vertebrate gut: focus on stomach and parietal cells in the marsupial,Macropus eugenii. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2009; 312:613-24. [DOI: 10.1002/jez.b.21227] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
34
|
Pearl EJ, Bilogan CK, Mukhi S, Brown DD, Horb ME. Xenopus pancreas development. Dev Dyn 2009; 238:1271-86. [PMID: 19334283 DOI: 10.1002/dvdy.21935] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Understanding how the pancreas develops is vital to finding new treatments for a range of pancreatic diseases, including diabetes and pancreatic cancer. Xenopus is a relatively new model organism for the elucidation of pancreas development, and has already made contributions to the field. Recent studies have shown benefits of using Xenopus for understanding both early patterning and lineage specification aspects of pancreas organogenesis. This review focuses specifically on Xenopus pancreas development, and covers events from the end of gastrulation, when regional specification of the endoderm is occurring, right through metamorphosis, when the mature pancreas is fully formed. We have attempted to cover pancreas development in Xenopus comprehensively enough to assist newcomers to the field and also to enable those studying pancreas development in other model organisms to better place the results from Xenopus research into the context of the field in general and their studies specifically. Developmental Dynamics 238:1271-1286, 2009. (c) 2009 Wiley-Liss, Inc.
Collapse
Affiliation(s)
- Esther J Pearl
- Laboratory of Molecular Organogenesis, Institut de Recherches Cliniques de Montréal, Montréal, QC Canada
| | | | | | | | | |
Collapse
|
35
|
Whole genome duplications and expansion of the vertebrate GATA transcription factor gene family. BMC Evol Biol 2009; 9:207. [PMID: 19695090 PMCID: PMC2857956 DOI: 10.1186/1471-2148-9-207] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Accepted: 08/20/2009] [Indexed: 01/12/2023] Open
Abstract
Background GATA transcription factors influence many developmental processes, including the specification of embryonic germ layers. The GATA gene family has significantly expanded in many animal lineages: whereas diverse cnidarians have only one GATA transcription factor, six GATA genes have been identified in many vertebrates, five in many insects, and eleven to thirteen in Caenorhabditis nematodes. All bilaterian animal genomes have at least one member each of two classes, GATA123 and GATA456. Results We have identified one GATA123 gene and one GATA456 gene from the genomic sequence of two invertebrate deuterostomes, a cephalochordate (Branchiostoma floridae) and a hemichordate (Saccoglossus kowalevskii). We also have confirmed the presence of six GATA genes in all vertebrate genomes, as well as additional GATA genes in teleost fish. Analyses of conserved sequence motifs and of changes to the exon-intron structure, and molecular phylogenetic analyses of these deuterostome GATA genes support their origin from two ancestral deuterostome genes, one GATA 123 and one GATA456. Comparison of the conserved genomic organization across vertebrates identified eighteen paralogous gene families linked to multiple vertebrate GATA genes (GATA paralogons), providing the strongest evidence yet for expansion of vertebrate GATA gene families via genome duplication events. Conclusion From our analysis, we infer the evolutionary birth order and relationships among vertebrate GATA transcription factors, and define their expansion via multiple rounds of whole genome duplication events. As the genomes of four independent invertebrate deuterostome lineages contain single copy GATA123 and GATA456 genes, we infer that the 0R (pre-genome duplication) invertebrate deuterostome ancestor also had two GATA genes, one of each class. Synteny analyses identify duplications of paralogous chromosomal regions (paralogons), from single ancestral vertebrate GATA123 and GATA456 chromosomes to four paralogons after the first round of vertebrate genome duplication, to seven paralogons after the second round of vertebrate genome duplication, and to fourteen paralogons after the fish-specific 3R genome duplication. The evolutionary analysis of GATA gene origins and relationships may inform understanding vertebrate GATA factor redundancies and specializations.
Collapse
|
36
|
GATA4 is a regulator of astrocyte cell proliferation and apoptosis in the human and murine central nervous system. Oncogene 2009; 28:3033-46. [PMID: 19543315 DOI: 10.1038/onc.2009.159] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The GATA transcription factors consist of six family members, which bind to the consensus DNA-binding element, W-GATA-R, and are poorly characterized in the central nervous system (CNS). Using retroviral gene trapping on transgenic mouse glioma models, we identified GATA6 to be a novel tumor suppressor gene in glioblastoma multiforme. We now show GATA4, a family member of GATA6, to be expressed in the neurons and glia of normal murine and human embryonic and adult CNS. Silencing GATA4 in normal astrocytes did not alter their growth properties. In contrast, knockdown of Gata4 in p53 null non-transformed murine astrocytes induced transformation, with increased proliferation and resistance to chemotherapy or radiation-induced apoptosis. Furthermore, GATA4 expression was lost in a panel of human malignant astrocytoma cell lines. GATA4 overexpression in normal human and murine astrocytes resulted in a cell cycle block in G1 phase, with increased apoptosis. Mechanistically, GATA4 was a transcriptional inducer of the cyclin-dependent kinase inhibitor, p15INK4B, leading to the attenuation of cyclin D1. GATA4 expression was also induced by transforming growth factor-beta, leading to the inhibition of astrocyte proliferation. Collectively, we show that GATA4 is expressed in the embryonic and adult CNS and acts as a negative regulator of astrocyte proliferation and growth.
Collapse
|
37
|
Asashima M, Ito Y, Chan T, Michiue T, Nakanishi M, Suzuki K, Hitachi K, Okabayashi K, Kondow A, Ariizumi T. In vitro organogenesis from undifferentiated cells inXenopus. Dev Dyn 2009; 238:1309-20. [DOI: 10.1002/dvdy.21979] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
|
38
|
Mould AW, Duncan R, Serewko-Auret M, Loffler KA, Biondi C, Gartside M, Kay GF, Hayward NK. Global expression profiling of sex cord stromal tumors fromMen1heterozygous mice identifies altered TGF-β signaling, decreased Gata6 and increased Csf1r expression. Int J Cancer 2009; 124:1122-32. [DOI: 10.1002/ijc.24057] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
39
|
Yagi Y, Ito Y, Kuhara S, Tashiro K. Cephalic hedgehog expression is regulated directly by Sox17 in endoderm development of Xenopus laevis. Cytotechnology 2008; 57:151-9. [PMID: 19003160 DOI: 10.1007/s10616-008-9127-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2007] [Accepted: 01/18/2008] [Indexed: 11/28/2022] Open
Abstract
In early development of animals, hedgehog (Hh) genes function as morphogen in the axis determination and the organ formation. In Xenopus, three hedgehog genes, sonic (shh), banded (bhh), and cephalic (chh), were identified and might organize various tissues and organs in embryogenesis. Here, we report the spatial and temporal regulation of Xchh which is expressed in endoderm cells differentiating to digestive organs. Xchh expression in endoderm was inhibited by ectopic expression of the dominant-negative activin receptor, tAR. Moreover, a maternally inherited transcription factor VegT and its downstream regulators activated Xchh expression. These indicates that Xchh is regulated by the factor involved in the cascade originated from VegT via activin/nodal signals. Using the Sox17alpha-VP16-GR construct, we showed that Xchh expression might be induced directly by transcription factor Sox17.
Collapse
Affiliation(s)
- Yumihiko Yagi
- Graduate School of Systems Life Sciences, Kyushu University, Hakozaki, Higashi-ku, Fukuoka, 812-8581, Japan
| | | | | | | |
Collapse
|
40
|
Smith J, Wardle F, Loose M, Stanley E, Patient R. Germ layer induction in ESC--following the vertebrate roadmap. ACTA ACUST UNITED AC 2008; Chapter 1:Unit 1D.1. [PMID: 18785165 DOI: 10.1002/9780470151808.sc01d01s1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Controlled differentiation of pluripotential cells takes place routinely and with great success in developing vertebrate embryos. It therefore makes sense to take note of how this is achieved and use this knowledge to control the differentiation of embryonic stem cells (ESCs). An added advantage is that the differentiated cells resulting from this process in embryos have proven functionality and longevity. This unit reviews what is known about the embryonic signals that drive differentiation in one of the most informative of the vertebrate animal models of development, the amphibian Xenopus laevis. It summarizes their identities and the extent to which their activities are dose-dependent. The unit details what is known about the transcription factor responses to these signals, describing the networks of interactions that they generate. It then discusses the target genes of these transcription factors, the effectors of the differentiated state. Finally, how these same developmental programs operate during germ layer formation in the context of ESC differentiation is summarized.
Collapse
Affiliation(s)
- Jim Smith
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, United Kingdom
| | | | | | | | | |
Collapse
|
41
|
Lavery DL, Martin J, Turnbull YD, Hoppler S. Wnt6 signaling regulates heart muscle development during organogenesis. Dev Biol 2008; 323:177-88. [PMID: 18804460 PMCID: PMC2593796 DOI: 10.1016/j.ydbio.2008.08.032] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2008] [Revised: 08/15/2008] [Accepted: 08/20/2008] [Indexed: 11/07/2022]
Abstract
Mesodermal tissue with heart forming potential (cardiogenic mesoderm) is induced during gastrulation. This cardiogenic mesoderm later differentiates into heart muscle tissue (myocardium) and non-muscular heart tissue. Inhibition of Wnt/β-catenin signaling is known to be required early for induction of cardiogenic mesoderm; however, the identity of the inhibiting Wnt signal itself is still elusive. We have identified Wnt6 in Xenopus as an endogenous Wnt signal, which is expressed in tissues close to and later inside the developing heart. Our loss-of-function experiments show that Wnt6 function is required in the embryo to prevent development of an abnormally large heart muscle. We find, however, that Wnt6 is not required as expected during gastrulation stages, but later during organogenesis stages just before cells of the cardiogenic mesoderm begin to differentiate into heart muscle (myocardium). Our gain-of-function experiments show that Wnt6 and also activated canonical Wnt/β-catenin signaling are capable of restricting heart muscle development at these relatively late stages of development. This repressive role of Wnt signaling is mediated initially via repression of cardiogenic transcription factors, since reinstatement of GATA function can rescue expression of other cardiogenic transcription factors and downstream cardiomyogenic differentiation genes.
Collapse
Affiliation(s)
- Danielle L Lavery
- Institute of Medical Sciences, Cell and Developmental Biology Research Programme, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, Scotland, UK
| | | | | | | |
Collapse
|
42
|
Woodland HR, Zorn AM. The core endodermal gene network of vertebrates: combining developmental precision with evolutionary flexibility. Bioessays 2008; 30:757-65. [DOI: 10.1002/bies.20785] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
43
|
zhang Y, Zhang FK, Wang BE. Advances in the relationship between canonical Wnt pathway and liver. Shijie Huaren Xiaohua Zazhi 2008; 16:975-981. [DOI: 10.11569/wcjd.v16.i9.975] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
A number of studies have demonstrated the important roles of canonical Wnt pathway in the essential physiologic processes in liver, such as development, growth, regeneration, zonation, metabolism, and oxidative stress. Likewise, there have been advances have been made in understanding the role of β-catenin in the development of various liver diseases. Studies of pathological specimens and rodent models of liver diseases have demonstrated aberrations in the canonical Wnt pathway in conditions ranging from hepatitis to hepatocellular carcinoma (HCC). In this article, we review the above roles of canonical Wnt pathway in liver health and diseases.
Collapse
|
44
|
van den Brink GR. Hedgehog signaling in development and homeostasis of the gastrointestinal tract. Physiol Rev 2007; 87:1343-75. [PMID: 17928586 DOI: 10.1152/physrev.00054.2006] [Citation(s) in RCA: 219] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The Hedgehog family of secreted morphogenetic proteins acts through a complex evolutionary conserved signaling pathway to regulate patterning events during development and in the adult organism. In this review I discuss the role of Hedgehog signaling in the development, postnatal maintenance, and carcinogenesis of the gastrointestinal tract. Three mammalian hedgehog genes, sonic hedgehog (Shh), indian hedgehog (Ihh), and desert hedgehog (Dhh) have been identified. Shh and Ihh are important endodermal signals in the endodermal-mesodermal cross-talk that patterns the developing gut tube along different axes. Mutations in Shh, Ihh, and downstream signaling molecules lead to a variety of gross malformations of the murine gastrointestinal tract including esophageal atresia, tracheoesophageal fistula, annular pancreas, midgut malrotation, and duodenal and anal atresia. These congenital malformations are also found in varying constellations in humans, suggesting a possible role for defective Hedgehog signaling in these patients. In the adult, Hedgehog signaling regulates homeostasis in several endoderm-derived epithelia, for example, the stomach, intestine, and pancreas. Finally, growth of carcinomas of the proximal gastrointestinal tract such as esophageal, gastric, biliary duct, and pancreatic cancers may depend on Hedgehog signaling offering a potential avenue for novel therapy for these aggressive cancers.
Collapse
Affiliation(s)
- Gijs R van den Brink
- Center for Experimental and Molecular Medicine, Academic Medical Center, Amsterdam, The Netherlands.
| |
Collapse
|
45
|
Dalgin G, Goldman DC, Donley N, Ahmed R, Eide CA, Christian JL. GATA-2 functions downstream of BMPs and CaM KIV in ectodermal cells during primitive hematopoiesis. Dev Biol 2007; 310:454-69. [PMID: 17850784 PMCID: PMC2049090 DOI: 10.1016/j.ydbio.2007.08.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2006] [Revised: 07/26/2007] [Accepted: 08/06/2007] [Indexed: 01/12/2023]
Abstract
In Xenopus, primitive blood originates from the mesoderm, but extrinsic signals from the ectoderm are required during gastrulation to enable these cells to differentiate as erythrocytes. The nature of these signals, and how they are transcriptionally regulated, is not well understood. We have previously shown that bone morphogenetic proteins (BMPs) are required to signal to ectodermal cells to generate secondary non-cell-autonomous signal(s) necessary for primitive erythropoiesis, and that calmodulin-dependent protein kinase IV (CaM KIV) antagonizes BMP signaling. The current studies demonstrate that Gata-2 functions downstream of BMP receptor activation in these same cells, and is a direct target for antagonism by CaM KIV. We show, using loss of function analysis in whole embryos and in explants, that ectodermal Gata-2 is required for primitive erythropoiesis, and that BMP signals cannot rescue blood defects caused by ectoderm removal or loss of ectodermal GATA-2. Furthermore, we provide evidence that acetylation of GATA-2 is required for its function in primitive blood formation in vivo. Our data support a model in which Gata-2 is a transcriptional target downstream of BMPs within ectodermal cells, while activation of the CaM KIV signaling pathway alters GATA-2 function posttranslationally, by inhibiting its acetylation.
Collapse
Affiliation(s)
- Gokhan Dalgin
- Department of Cell and Developmental Biology Oregon Health and Science University, School of Medicine 3181 SW Sam Jackson Park Road Portland, OR 97239-3098
| | - Devorah C. Goldman
- Department of Cell and Developmental Biology Oregon Health and Science University, School of Medicine 3181 SW Sam Jackson Park Road Portland, OR 97239-3098
| | - Nathan Donley
- Department of Cell and Developmental Biology Oregon Health and Science University, School of Medicine 3181 SW Sam Jackson Park Road Portland, OR 97239-3098
| | - Riffat Ahmed
- Department of Cell and Developmental Biology Oregon Health and Science University, School of Medicine 3181 SW Sam Jackson Park Road Portland, OR 97239-3098
| | - Christopher A. Eide
- Department of Cell and Developmental Biology Oregon Health and Science University, School of Medicine 3181 SW Sam Jackson Park Road Portland, OR 97239-3098
| | - Jan L. Christian
- Department of Cell and Developmental Biology Oregon Health and Science University, School of Medicine 3181 SW Sam Jackson Park Road Portland, OR 97239-3098
| |
Collapse
|
46
|
Morris SA, Almeida AD, Tanaka H, Ohta K, Ohnuma SI. Tsukushi modulates Xnr2, FGF and BMP signaling: regulation of Xenopus germ layer formation. PLoS One 2007; 2:e1004. [PMID: 17925852 PMCID: PMC1994590 DOI: 10.1371/journal.pone.0001004] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Accepted: 09/11/2007] [Indexed: 11/28/2022] Open
Abstract
Background Cell-cell communication is essential in tissue patterning. In early amphibian development, mesoderm is formed in the blastula-stage embryo through inductive interactions in which vegetal cells act on overlying equatorial cells. Members of the TGF-β family such as activin B, Vg1, derrière and Xenopus nodal-related proteins (Xnrs) are candidate mesoderm inducing factors, with further activity to induce endoderm of the vegetal region. TGF-β-like ligands, including BMP, are also responsible for patterning of germ layers. In addition, FGF signaling is essential for mesoderm formation whereas FGF signal inhibition has been implicated in endoderm induction. Clearly, several signaling pathways are coordinated to produce an appropriate developmental output; although intracellular crosstalk is known to integrate multiple pathways, relatively little is known about extracellular coordination. Methodology/Principal Findings Here, we show that Xenopus Tsukushi (X-TSK), a member of the secreted small leucine rich repeat proteoglycan (SLRP) family, is expressed in ectoderm, endoderm, and the organizer during early development. We have previously reported that X-TSK binds to and inhibits BMP signaling in cooperation with chordin. We now demonstrate two novel interactions: X-TSK binds to and inhibits signaling by FGF8b, in addition to binding to and enhancement of Xnr2 signaling. This signal integration by X-TSK at the extracellular level has an important role in germ layer formation and patterning. Vegetally localized X-TSK potentiates endoderm formation through coordination of BMP, FGF and Xnr2 signaling. In contrast, X-TSK inhibition of FGF-MAPK signaling blocks ventrolateral mesoderm formation, while BMP inhibition enhances organizer formation. These actions of X-TSK are reliant upon its expression in endoderm and dorsal mesoderm, with relative exclusion from ventrolateral mesoderm, in a pattern shaped by FGF signals. Conclusions/Significance Based on our observations, we propose a novel mechanism by which X-TSK refines the field of positional information by integration of multiple pathways in the extracellular space.
Collapse
Affiliation(s)
- Samantha A. Morris
- Department of Oncology, The Hutchison/Medical Research Council Research Centre, University of Cambridge, Cambridge, United Kingdom
- * To whom correspondence should be addressed. E-mail: (SM); (SO)
| | - Alexandra D. Almeida
- Department of Oncology, The Hutchison/Medical Research Council Research Centre, University of Cambridge, Cambridge, United Kingdom
| | - Hideaki Tanaka
- Department of Developmental Neurobiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Kunimasa Ohta
- Department of Developmental Neurobiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Shin-ichi Ohnuma
- Department of Oncology, The Hutchison/Medical Research Council Research Centre, University of Cambridge, Cambridge, United Kingdom
- * To whom correspondence should be addressed. E-mail: (SM); (SO)
| |
Collapse
|
47
|
Peterkin T, Gibson A, Patient R. Redundancy and evolution of GATA factor requirements in development of the myocardium. Dev Biol 2007; 311:623-35. [PMID: 17869240 PMCID: PMC2279743 DOI: 10.1016/j.ydbio.2007.08.018] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2007] [Revised: 08/01/2007] [Accepted: 08/07/2007] [Indexed: 11/26/2022]
Abstract
The transcription factors, GATA4, 5 and 6, recognize the same DNA sequence and are all expressed in the developing myocardium. However, knockout studies in the mouse have indicated that none of them are absolutely required for the specification of the myocardium. Here we present evidence for redundancy in this family for the first time. Using morpholinos in both Xenopus and zebrafish embryos, we show that GATA4 knockdown, for example, only affects cardiac marker expression in the absence of either GATA5 or GATA6. A similar situation pertains for GATA5 in Xenopus whereas, in zebrafish, GATA5 (faust) plays a major role in driving the myocardial programme. This requirement for GATA5 in zebrafish is for induction of the myocardium, in contrast to the GATA6 requirement in both species, which is for differentiation. This early role for GATA5 in zebrafish correlates with its earlier expression and with an earlier requirement for BMP signalling, suggesting that a mutual maintenance loop for GATA, BMP and Nkx expression is the evolutionarily conserved entity.
Collapse
Affiliation(s)
- Tessa Peterkin
- Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK
| | - Abigail Gibson
- The Victor Chang Cardiac Research Institute, Level 6, 384 Victoria Street, Darlinghurst, NSW 2010, Sydney, Australia
| | - Roger Patient
- Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK
- Corresponding author. Fax: +441865222501.
| |
Collapse
|
48
|
Howard L, Rex M, Clements D, Woodland HR. Regulation of the Xenopus Xsox17alpha(1) promoter by co-operating VegT and Sox17 sites. Dev Biol 2007; 310:402-15. [PMID: 17719026 PMCID: PMC2098691 DOI: 10.1016/j.ydbio.2007.07.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2007] [Revised: 07/03/2007] [Accepted: 07/23/2007] [Indexed: 11/23/2022]
Abstract
The gene encoding the Sox F-group transcription factor Xsox17α1 is specifically expressed throughout the entire region of the Xenopus blastula fated to become endoderm, and is important in controlling endodermal development. Xsox17α1 is a direct target of the maternal endodermal determinant VegT and of Sox17 itself. We have analysed the promoter of the Xenopus laevis Xsox17α1 gene by transgenesis, and have identified two important control elements which reside about 9 kb upstream at the start of transcription. These elements individually drive transgenic endodermal expression in the blastula and gastrula. One contains functional, cooperating VegT and Sox-binding consensus sites. The Sox sites in this region are occupied in vivo. The other responds to TGF-β signals like Activin or Nodals that act through Smad2/3. We propose that these two regions co-operate in regulating the early endodermal expression of the Xsox17α1 gene.
Collapse
|
49
|
Belaguli NS, Zhang M, Rigi M, Aftab M, Berger DH. Cooperation between GATA4 and TGF-beta signaling regulates intestinal epithelial gene expression. Am J Physiol Gastrointest Liver Physiol 2007; 292:G1520-33. [PMID: 17290010 DOI: 10.1152/ajpgi.00236.2006] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Members of the transforming growth factor-beta (TGF-beta) family have been shown to play an important role in the regulation of gut epithelial gene expression. We have used the intestinal alkaline phosphatase (IAP) and intestinal fatty acid binding protein (IFABP) promoters to dissect the mechanisms by which TGF-beta1 signaling regulates gut epithelial gene expression. TGF-beta signaling alone was not sufficient for activation of IAP and IFABP promoters. However, TGF-beta signaling cooperated with the gut epithelial transcription factor GATA4 to synergistically activate IAP and IFABP promoters. Coexpression of GATA4 along with the TGF-beta1 signal transducing downstream effectors such as Smad2, 3, and 4 resulted in synergistic activation of both IAP and IFABP promoters. This synergistic activation was reduced by simultaneous expression of dominant-negative Smad4. -40 and -89 GATA binding sites in the IFABP promoter were required for the synergistic activation by Smad2, 3, and 4 and GATA4. GATA4 and Smad2, 3, and 4 physically associated with each other and this interaction was mediated through the MH2 domain of Smad2, 3, and 4 and the second zinc finger and the COOH-terminal basic domain of GATA4. The COOH-terminal activation domain and the Smad-interacting second zinc finger domain of GATA4 were required for the synergistic activation of the IFABP promoter. Naturally occurring oncogenic mutations within the GATA4-interacting MH2 domain of Smad2 reduced the coactivation of IFABP promoter by Smad2 and GATA4. Our results suggest that the TGF-beta signaling regulates gut epithelial gene expression by targeting GATA4.
Collapse
MESH Headings
- Activin Receptors, Type I/metabolism
- Alkaline Phosphatase
- Animals
- Antigens, Neoplasm/genetics
- Antigens, Neoplasm/metabolism
- Epithelial Cells/metabolism
- Epithelial Cells/pathology
- Fatty Acid-Binding Proteins/genetics
- Fatty Acid-Binding Proteins/metabolism
- GATA4 Transcription Factor/chemistry
- GATA4 Transcription Factor/genetics
- GATA4 Transcription Factor/metabolism
- GPI-Linked Proteins
- Gene Expression
- Genes, Reporter
- HCT116 Cells
- Haplorhini
- Humans
- Intestinal Mucosa/metabolism
- Intestinal Mucosa/pathology
- Luciferases
- Mutation
- Promoter Regions, Genetic
- Protein Binding
- Protein Serine-Threonine Kinases
- Protein Structure, Tertiary
- RNA Interference
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- Receptor, Transforming Growth Factor-beta Type I
- Receptors, Transforming Growth Factor beta/metabolism
- Signal Transduction/genetics
- Smad2 Protein/metabolism
- Smad3 Protein/metabolism
- Smad4 Protein/metabolism
- Transfection
- Transforming Growth Factor beta1/genetics
- Transforming Growth Factor beta1/metabolism
- Zinc Fingers
Collapse
Affiliation(s)
- Narasimhaswamy S Belaguli
- Michael E. DeBakey Dept. of Surgery, Michael E. DeBakey VA Medical Center, Baylor College of Medicine, 2002 Holcombe Blvd., Houston, Texas 77030, USA.
| | | | | | | | | |
Collapse
|
50
|
Evolution of the mechanisms and molecular control of endoderm formation. Mech Dev 2007; 124:253-78. [PMID: 17307341 DOI: 10.1016/j.mod.2007.01.001] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2006] [Revised: 12/24/2006] [Accepted: 01/03/2007] [Indexed: 01/13/2023]
Abstract
Endoderm differentiation and movements are of fundamental importance not only for subsequent morphogenesis of the digestive tract but also to enable normal patterning and differentiation of mesoderm- and ectoderm-derived organs. This review defines the tissues that have been called endoderm in different species, their cellular origin and their movements. We take a comparative approach to ask how signaling pathways leading to embryonic and extraembryonic endoderm differentiation have emerged in different organisms, how they became integrated and point to specific gaps in our knowledge that would be worth filling. Lastly, we address whether the gastrulation movements that lead to endoderm internalization are coupled with its differentiation.
Collapse
|