101
|
Lewis SL, Tam PPL. Definitive endoderm of the mouse embryo: formation, cell fates, and morphogenetic function. Dev Dyn 2006; 235:2315-29. [PMID: 16752393 DOI: 10.1002/dvdy.20846] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The endoderm is one of the primary germ layers but, in comparison to ectoderm and mesoderm, has received less attention. The definitive endoderm forms during gastrulation and replaces the extraembryonic visceral endoderm. It participates in the complex morphogenesis of the gut tube and contributes to the associated visceral organs. This review highlights the role of the definitive endoderm as a source of patterning cues for the morphogenesis of other germ-layer tissues, such as the anterior neurectoderm and the pharyngeal region, and also emphasizes the intricate patterning that the endoderm itself undergoes enabling the acquisition of regionalized cell fates.
Collapse
Affiliation(s)
- Samara L Lewis
- Embryology Unit, Children's Medical Research Institute, University of Sydney, Sydney, NSW, Australia
| | | |
Collapse
|
102
|
Wang J, Nagy A, Larsson J, Dudas M, Sucov HM, Kaartinen V. Defective ALK5 signaling in the neural crest leads to increased postmigratory neural crest cell apoptosis and severe outflow tract defects. BMC DEVELOPMENTAL BIOLOGY 2006; 6:51. [PMID: 17078885 PMCID: PMC1635039 DOI: 10.1186/1471-213x-6-51] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Accepted: 11/01/2006] [Indexed: 01/05/2023]
Abstract
Background Congenital cardiovascular diseases are the most common form of birth defects in humans. A substantial portion of these defects has been associated with inappropriate induction, migration, differentiation and patterning of pluripotent cardiac neural crest stem cells. While TGF-β-superfamily signaling has been strongly implicated in neural crest cell development, the detailed molecular signaling mechanisms in vivo are still poorly understood. Results We deleted the TGF-β type I receptor Alk5 specifically in the mouse neural crest cell lineage. Failure in signaling via ALK5 leads to severe cardiovascular and pharyngeal defects, including inappropriate remodeling of pharyngeal arch arteries, abnormal aortic sac development, failure in pharyngeal organ migration and persistent truncus arteriosus. While ALK5 is not required for neural crest cell migration, our results demonstrate that it plays an important role in the survival of post-migratory cardiac neural crest cells. Conclusion Our results demonstrate that ALK5-mediated signaling in neural crest cells plays an essential cell-autonomous role in the pharyngeal and cardiac outflow tract development.
Collapse
MESH Headings
- Activin Receptors, Type I/deficiency
- Activin Receptors, Type I/genetics
- Activin Receptors, Type I/physiology
- Animals
- Aorta/abnormalities
- Aorta/embryology
- Apoptosis/genetics
- Branchial Region/abnormalities
- Branchial Region/embryology
- Cell Movement/genetics
- Female
- Heart Defects, Congenital/embryology
- Heart Defects, Congenital/genetics
- Mice
- Mice, Knockout
- Mice, Transgenic
- Neural Crest/embryology
- Neural Crest/pathology
- Protein Serine-Threonine Kinases
- Receptor, Transforming Growth Factor-beta Type I
- Receptors, Transforming Growth Factor beta/deficiency
- Receptors, Transforming Growth Factor beta/genetics
- Receptors, Transforming Growth Factor beta/physiology
- Signal Transduction/genetics
Collapse
Affiliation(s)
- Jikui Wang
- Developmental Biology Program, The Saban Research Institute of Childrens Hospital Los Angeles, Departments of Pathology and Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA 90027, USA
| | - Andre Nagy
- Developmental Biology Program, The Saban Research Institute of Childrens Hospital Los Angeles, Departments of Pathology and Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA 90027, USA
| | - Jonas Larsson
- Molecular Medicine and Gene Therapy, Institute of Laboratory Medicine and Department of Medicine, Lund University Hospital, 221 00 Lund, Sweden
| | - Marek Dudas
- Developmental Biology Program, The Saban Research Institute of Childrens Hospital Los Angeles, Departments of Pathology and Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA 90027, USA
| | - Henry M Sucov
- Institute for Genetic Medicine, Keck School of Medicine University of Southern California, Los Angeles, CA 90033, USA
| | - Vesa Kaartinen
- Developmental Biology Program, The Saban Research Institute of Childrens Hospital Los Angeles, Departments of Pathology and Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA 90027, USA
| |
Collapse
|
103
|
Abstract
The development of the parathyroid glands involves complex embryonic processes of cell-specific differentiation and migration of the glands from their sites of origin in the pharynx and pharyngeal pouches to their final positions along the ventral midline of the pharyngeal and upper thoracic region. The recognition of several distinct genetic forms of isolated and syndromic hypoparathyroidism led us to review the recent findings on the molecular mechanisms of the development of the parathyroid glands. Although far from being understood, a special emphasis was given to the possible role of tubulin chaperone E (TBCE), which was implicated in the pathogenesis of the hypopathyroidism, retardation and dysmorphism (HRD) syndrome. The novel finding that TBCE plays a critical role in the formation of the parathyroid opens a novel domain of research, not anticipated previously, into the complex process of parathyroid development.
Collapse
Affiliation(s)
- Ruti Parvari
- Department of Developmental Genetics and Virology, Faculty of Health Sciences and National Institute for Biotechnology, Ben Gurion University of the Negev, Beer Sheva, Israel.
| | | | | |
Collapse
|
104
|
Park EJ, Ogden LA, Talbot A, Evans S, Cai CL, Black BL, Frank DU, Moon AM. Required, tissue-specific roles for Fgf8 in outflow tract formation and remodeling. Development 2006; 133:2419-33. [PMID: 16720879 PMCID: PMC1780034 DOI: 10.1242/dev.02367] [Citation(s) in RCA: 216] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Fibroblast growth factor 8 (Fgf8) is a secreted signaling protein expressed in numerous temporospatial domains that are potentially relevant to cardiovascular development. However, the pathogenesis of complex cardiac and outflow tract defects observed in Fgf8-deficient mice, and the specific source(s) of Fgf8 required for outflow tract formation and subsequent remodeling are unknown. A detailed examination of the timing and location of Fgf8 production revealed previously unappreciated expression in a subset of primary heart field cells; Fgf8 is also expressed throughout the anterior heart field (AHF) mesoderm and in pharyngeal endoderm at the crescent and early somite stages. We used conditional mutagenesis to examine the requirements for Fgf8 function in these different expression domains during heart and outflow tract morphogenesis. Formation of the primary heart tube and the addition of right ventricular and outflow tract myocardium depend on autocrine Fgf8 signaling in cardiac crescent mesoderm. Loss of Fgf8 in this domain resulted in decreased expression of the Fgf8 target gene Erm, and aberrant production of Isl1 and its target Mef2c in the anterior heart field, thus linking Fgf8 signaling with transcription factor networks that regulate survival and proliferation of the anterior heart field. We further found that mesodermal- and endodermal-derived Fgf8 perform specific functions during outflow tract remodeling: mesodermal Fgf8 is required for correct alignment of the outflow tract and ventricles, whereas activity of Fgf8 emanating from pharyngeal endoderm regulates outflow tract septation. These findings provide a novel insight into how the formation and remodeling of primary and anterior heart field-derived structures rely on Fgf8 signals from discrete temporospatial domains.
Collapse
Affiliation(s)
- Eon Joo Park
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | | | | | | | | | | | | | | |
Collapse
|
105
|
Maynard TM, Meechan DW, Heindel CC, Peters AZ, Hamer RM, Lieberman JA, LaMantia AS. No evidence for parental imprinting of mouse 22q11 gene orthologs. Mamm Genome 2006; 17:822-32. [PMID: 16897343 PMCID: PMC2663429 DOI: 10.1007/s00335-006-0011-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Accepted: 03/27/2006] [Indexed: 10/24/2022]
Abstract
Non-Mendelian factors may influence central nervous system (CNS) phenotypes in patients with 22q11 Deletion Syndrome (22q11DS, also known as DiGeorge or Velocardiofacial Syndrome), and similar mechanisms may operate in mice carrying a deletion of one or more 22q11 gene orthologs. Accordingly, we examined the influence of parent of origin on expression of 25 murine 22q11 orthologs in the developing and mature CNS using single nucleotide polymorphism (SNP)-based analysis in interspecific crosses and quantification of mRNA in a murine model of 22q11DS. We found no evidence for absolute genomic imprinting or silencing. All 25 genes are biallelically expressed in the developing and adult brains. Furthermore, if more subtle forms of allelic biasing are present, they are very small in magnitude and most likely beyond the resolution of currently available quantitative approaches. Given the high degree of similarity of human 22q11 and the orthologous region of mmChr16, genomic imprinting most likely cannot explain apparent parent-of-origin effects in 22q11DS.
Collapse
Affiliation(s)
- Thomas M Maynard
- UNC Silvio O. Conte Center for the Neuroscience of Mental Disorders, University of North Carolina, Chapel Hill, North Carolina, 27599, USA
| | | | | | | | | | | | | |
Collapse
|
106
|
Zhang X, Ibrahimi OA, Olsen SK, Umemori H, Mohammadi M, Ornitz DM. Receptor specificity of the fibroblast growth factor family. The complete mammalian FGF family. J Biol Chem 2006; 281:15694-700. [PMID: 16597617 PMCID: PMC2080618 DOI: 10.1074/jbc.m601252200] [Citation(s) in RCA: 874] [Impact Index Per Article: 48.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
In mammals, fibroblast growth factors (FGFs) are encoded by 22 genes. FGFs bind and activate alternatively spliced forms of four tyrosine kinase FGF receptors (FGFRs 1-4). The spatial and temporal expression patterns of FGFs and FGFRs and the ability of specific ligand-receptor pairs to actively signal are important factors regulating FGF activity in a variety of biological processes. FGF signaling activity is regulated by the binding specificity of ligands and receptors and is modulated by extrinsic cofactors such as heparan sulfate proteoglycans. In previous studies, we have engineered BaF3 cell lines to express the seven principal FGFRs and used these cell lines to determine the receptor binding specificity of FGFs 1-9 by using relative mitogenic activity as the readout. Here we have extended these semiquantitative studies to assess the receptor binding specificity of the remaining FGFs 10-23. This study completes the mitogenesis-based comparison of receptor specificity of the entire FGF family under standard conditions and should help in interpreting and predicting in vivo biological activity.
Collapse
Affiliation(s)
- Xiuqin Zhang
- Department of Molecular Biology and Pharmacology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Omar A. Ibrahimi
- Department of Pharmacology, New York University School of Medicine, New York, New York 10016
| | - Shaun K. Olsen
- Department of Pharmacology, New York University School of Medicine, New York, New York 10016
| | - Hisashi Umemori
- Department of Biological Chemistry, Molecular & Behavioral Neuroscience Institute, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Moosa Mohammadi
- Department of Pharmacology, New York University School of Medicine, New York, New York 10016
| | - David M. Ornitz
- Department of Molecular Biology and Pharmacology, Washington University School of Medicine, St. Louis, Missouri 63110
| |
Collapse
|
107
|
Abstract
Clinicians and basic scientists share an interest in discovering how genetic or environmental factors interact to perturb normal development and cause birth defects and human disease. Given the complexity of such interactions, it is not surprising that 4% of human infants are born with a congenital malformation, and cardiovascular defects occur in nearly 1%. Our research is based on the fundamental hypothesis that an understanding of normal and abnormal development will permit us to generate effective strategies for both prevention and treatment of human birth defects. Animal models are invaluable in these efforts because they allow one to interrogate the genetic, molecular and cellular events that distinguish normal from abnormal development. Several features of the mouse make it a particularly powerful experimental model: it is a mammalian system with similar embryology, anatomy and physiology to humans; genes, proteins and regulatory programs are largely conserved between human and mouse; and finally, gene targeting in murine embryonic stem cells has made the mouse genome amenable to sophisticated genetic manipulation currently unavailable in any other model organism.
Collapse
Affiliation(s)
- Anne M Moon
- Department of Neurobiology, and Program in Human Molecular Biology and Genetics, University of Utah, School of Medicine, Salt Lake City, UT 84112, USA.
| |
Collapse
|
108
|
Vitelli F, Zhang Z, Huynh T, Sobotka A, Mupo A, Baldini A. Fgf8 expression in the Tbx1 domain causes skeletal abnormalities and modifies the aortic arch but not the outflow tract phenotype of Tbx1 mutants. Dev Biol 2006; 295:559-70. [PMID: 16696966 PMCID: PMC1850621 DOI: 10.1016/j.ydbio.2006.03.044] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2006] [Revised: 03/22/2006] [Accepted: 03/28/2006] [Indexed: 11/17/2022]
Abstract
Fgf8 and Tbx1 have been shown to interact in patterning the aortic arch, and both genes are required in formation and growth of the outflow tract of the heart. However, the nature of the interaction of the two genes is unclear. We have utilized a novel Tbx1(Fgf8) allele which drives Fgf8 expression in Tbx1-positive cells and an inducible Cre-LoxP recombination system to address the role of Fgf8 in Tbx1 positive cells in modulating cardiovascular development. Results support a requirement of Fgf8 in Tbx1 expressing cells to finely control patterning of the aortic arch and great arteries specifically during the pharyngeal arch artery remodeling process and indicate that the endoderm is the most likely site of this interaction. Furthermore, our data suggest that Fgf8 and Tbx1 play independent roles in regulating outflow tract development. This finding is clinically relevant since TBX1 is the candidate for DGS/VCFS, characterized clinically by variable expressivity and reduced penetrance of cardiovascular defects; Fgf8 gene variants may provide molecular clues to this variability.
Collapse
Affiliation(s)
- Francesca Vitelli
- Department of Pediatrics, Cardiology, Baylor College of Medicine, 1102 Bates St, RM FC450.03, Houston, TX 77030, USA.
| | | | | | | | | | | |
Collapse
|
109
|
Guris DL, Duester G, Papaioannou VE, Imamoto A. Dose-dependent interaction of Tbx1 and Crkl and locally aberrant RA signaling in a model of del22q11 syndrome. Dev Cell 2006; 10:81-92. [PMID: 16399080 DOI: 10.1016/j.devcel.2005.12.002] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2005] [Revised: 11/17/2005] [Accepted: 12/06/2005] [Indexed: 10/25/2022]
Abstract
22q11 deletion (del22q11) syndrome is characterized genetically by heterozygous deletions within chromosome 22q11 and clinically by a constellation of congenital malformations of the aortic arch, heart, thymus, and parathyroid glands described as DiGeorge syndrome (DGS). Here, we report that compound heterozygosity of mouse homologs of two 22q11 genes, CRKL and TBX1, results in a striking increase in the penetrance and expressivity of a DGS-like phenotype compared to heterozygosity at either locus. Furthermore, we show that these two genes have critical dose-dependent functions in pharyngeal segmentation, patterning of the pharyngeal apparatus along the anteroposterior axis, and local regulation of retinoic acid (RA) metabolism and signaling. We can partially rescue one salient feature of DGS in Crkl+/-;Tbx1+/- embryos by genetically reducing the amount of RA produced in the embryo. Thus, we suggest that del22q11 is a contiguous gene syndrome involving dose-sensitive interaction of CRKL and TBX1 and locally aberrant RA signaling.
Collapse
Affiliation(s)
- Deborah L Guris
- The Ben May Institute for Cancer Research and Center for Molecular Oncology, The University of Chicago, Chicago, Illinois 60637, USA
| | | | | | | |
Collapse
|
110
|
Abstract
DiGeorge syndrome is the most frequent microdeletion syndrome in humans, and is characterized by cardiovascular, thymic and parathyroid, and craniofacial anomalies. The underlying cause is disturbed formation of the pharyngeal apparatus, a transient structure present during vertebrate development that gives rise to endocrine glands, craniofacial tissue, and the cardiac outflow tract. The pharyngeal apparatus is composed of derivatives of ectoderm, endoderm, mesoderm and the neural crest. Thus, complex interactions between cell types from different origins have to be orchestrated in the correct spatiotemporal manner to establish proper formation of the pharyngeal system. The analysis of engineered mouse mutants developing a phenotype resembling DiGeorge syndrome has revealed genes and signalling pathways crucial for this process. Intriguingly, these mouse models reveal that interference with either of two distinct phases of pharyngeal apparatus development can contribute to the aetiology of DiGeorge syndrome.
Collapse
Affiliation(s)
- Heiko Wurdak
- Institute of Cell Biology, Department of Biology, ETH Zurich, ETH-Hönggerberg, Zurich, Switzerland
| | | | | |
Collapse
|