51
|
Stundl J, Pospisilova A, Jandzik D, Fabian P, Dobiasova B, Minarik M, Metscher BD, Soukup V, Cerny R. Bichir external gills arise via heterochronic shift that accelerates hyoid arch development. eLife 2019; 8:43531. [PMID: 30910008 PMCID: PMC6440740 DOI: 10.7554/elife.43531] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 03/15/2019] [Indexed: 12/25/2022] Open
Abstract
In most vertebrates, pharyngeal arches form in a stereotypic anterior-to-posterior progression. To gain insight into the mechanisms underlying evolutionary changes in pharyngeal arch development, here we investigate embryos and larvae of bichirs. Bichirs represent the earliest diverged living group of ray-finned fishes, and possess intriguing traits otherwise typical for lobe-finned fishes such as ventral paired lungs and larval external gills. In bichir embryos, we find that the anteroposterior way of formation of cranial segments is modified by the unique acceleration of the entire hyoid arch segment, with earlier and orchestrated development of the endodermal, mesodermal, and neural crest tissues. This major heterochronic shift in the anteroposterior developmental sequence enables early appearance of the external gills that represent key breathing organs of bichir free-living embryos and early larvae. Bichirs thus stay as unique models for understanding developmental mechanisms facilitating increased breathing capacity.
Collapse
Affiliation(s)
- Jan Stundl
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic.,National Museum, Prague, Czech Republic
| | - Anna Pospisilova
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - David Jandzik
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic.,Department of Zoology, Faculty of Natural Sciences, Comenius University in Bratislava, Bratislava, Slovakia
| | - Peter Fabian
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Barbora Dobiasova
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Martin Minarik
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Brian D Metscher
- Department of Theoretical Biology, University of Vienna, Vienna, Austria
| | - Vladimir Soukup
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Robert Cerny
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| |
Collapse
|
52
|
Li L, Ning G, Yang S, Yan Y, Cao Y, Wang Q. BMP signaling is required for nkx2.3-positive pharyngeal pouch progenitor specification in zebrafish. PLoS Genet 2019; 15:e1007996. [PMID: 30763319 PMCID: PMC6392332 DOI: 10.1371/journal.pgen.1007996] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 02/27/2019] [Accepted: 01/29/2019] [Indexed: 12/13/2022] Open
Abstract
Pharyngeal pouches, a series of outpocketings that bud from the foregut endoderm, are essential to the formation of craniofacial skeleton as well as several important structures like parathyroid and thymus. However, whether pharyngeal pouch progenitors exist in the developing gut tube remains unknown. Here, taking advantage of cell lineage tracing and transgenic ablation technologies, we identified a population of nkx2.3+ pouch progenitors in zebrafish embryos and demonstrated an essential requirement of ectodermal BMP2b for their specification. At early somite stages, nkx2.3+ cells located at lateral region of pharyngeal endoderm give rise to the pouch epithelium except a subpopulation expressing pdgfαa rather than nkx2.3. A small-scale screen of chemical inhibitors reveals that BMP signaling is necessary to specify these progenitors. Loss-of-function analyses show that BMP2b, expressed in the pharyngeal ectoderm, actives Smad effectors in endodermal cells to induce nkx2.3+ progenitors. Collectively, our study provides in vivo evidence for the existence of pouch progenitors and highlights the importance of BMP2b signaling in progenitor specification. Pharyngeal pouches are essential to the formation of craniofacial skeleton as well as several important structures like parathyroid and thymus, but whether their progenitors exist in the developing gut tube remains unknown. Our study provide in vivo evidence that, in the early somite stages, nkx2.3+ cells are present in the lateral pharyngeal endoderm and give rise to the pouch epithelium. We further reveal that ectodermal BMP2b is essential for the activation of Smad effectors in endodermal cells, thereby facilitating pouch progenitor specification. Collectively, our discoveries shed new light on the cellular and molecular mechanisms of pharyngeal pouch development.
Collapse
Affiliation(s)
- Linwei Li
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
| | - Guozhu Ning
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
| | - Shuyan Yang
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
| | - Yifang Yan
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
| | - Yu Cao
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
| | - Qiang Wang
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
- * E-mail:
| |
Collapse
|
53
|
Kindberg AA, Bush JO. Cellular organization and boundary formation in craniofacial development. Genesis 2019; 57:e23271. [PMID: 30548771 PMCID: PMC6503678 DOI: 10.1002/dvg.23271] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 12/07/2018] [Accepted: 12/10/2018] [Indexed: 12/24/2022]
Abstract
Craniofacial morphogenesis is a highly dynamic process that requires changes in the behaviors and physical properties of cells in order to achieve the proper organization of different craniofacial structures. Boundary formation is a critical process in cellular organization, patterning, and ultimately tissue separation. There are several recurring cellular mechanisms through which boundary formation and cellular organization occur including, transcriptional patterning, cell segregation, cell adhesion and migratory guidance. Disruption of normal boundary formation has dramatic morphological consequences, and can result in human craniofacial congenital anomalies. In this review we discuss boundary formation during craniofacial development, specifically focusing on the cellular behaviors and mechanisms underlying the self-organizing properties that are critical for craniofacial morphogenesis.
Collapse
Affiliation(s)
- Abigail A. Kindberg
- Department of Cell and Tissue Biology, Program in Craniofacial Biology, and Institute of Human Genetics, University of California at San Francisco, San Francisco, CA 94143, USA
| | - Jeffrey O. Bush
- Department of Cell and Tissue Biology, Program in Craniofacial Biology, and Institute of Human Genetics, University of California at San Francisco, San Francisco, CA 94143, USA
| |
Collapse
|
54
|
Li L, Mao A, Wang P, Ning G, Cao Y, Wang Q. Endodermal pouch-expressed dmrt2b is important for pharyngeal cartilage formation. Biol Open 2018; 7:bio.035444. [PMID: 30341107 PMCID: PMC6310889 DOI: 10.1242/bio.035444] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Pharyngeal pouches, a series of outpocketings derived from the foregut endoderm, are essential for craniofacial skeleton formation. However, the molecular mechanisms underlying endodermal pouch-regulated head cartilage development are not fully understood. In this study, we find that zebrafish dmrt2b, a gene encoding Doublesex- and Mab-3-related transcription factor, is specifically expressed in endodermal pouches and required for normal pharyngeal cartilage development. Loss of dmrt2b doesn't affect cranial neural crest (CNC) specification and migration, but leads to prechondrogenic condensation defects by reducing cxcl12b expression after CNC cell movement into the pharyngeal arches. Moreover, dmrt2b inactivation results in reduced proliferation and impaired differentiation of CNC cells. We also show that dmrt2b suppresses crossveinless 2 expression in endodermal pouches to maintain BMP/Smad signaling in the arches, thereby facilitating CNC cell proliferation and chondrogenic differentiation. This work provides insight into how transcription factors expressed in endodermal pouches regulate pharyngeal skeleton development through tissue-tissue interactions.
Collapse
Affiliation(s)
- Linwei Li
- State Key Laboratory of Membrane Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Aihua Mao
- State Key Laboratory of Membrane Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Peng Wang
- State Key Laboratory of Membrane Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Guozhu Ning
- State Key Laboratory of Membrane Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Yu Cao
- State Key Laboratory of Membrane Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Qiang Wang
- State Key Laboratory of Membrane Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China .,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China
| |
Collapse
|
55
|
Meinecke L, Sharma PP, Du H, Zhang L, Nie Q, Schilling TF. Modeling craniofacial development reveals spatiotemporal constraints on robust patterning of the mandibular arch. PLoS Comput Biol 2018; 14:e1006569. [PMID: 30481168 PMCID: PMC6258504 DOI: 10.1371/journal.pcbi.1006569] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 10/16/2018] [Indexed: 12/11/2022] Open
Abstract
How does pattern formation occur accurately when confronted with tissue growth and stochastic fluctuations (noise) in gene expression? Dorso-ventral (D-V) patterning of the mandibular arch specifies upper versus lower jaw skeletal elements through a combination of Bone morphogenetic protein (Bmp), Endothelin-1 (Edn1), and Notch signaling, and this system is highly robust. We combine NanoString experiments of early D-V gene expression with live imaging of arch development in zebrafish to construct a computational model of the D-V mandibular patterning network. The model recapitulates published genetic perturbations in arch development. Patterning is most sensitive to changes in Bmp signaling, and the temporal order of gene expression modulates the response of the patterning network to noise. Thus, our integrated systems biology approach reveals non-intuitive features of the complex signaling system crucial for craniofacial development, including novel insights into roles of gene expression timing and stochasticity in signaling and gene regulation.
Collapse
Affiliation(s)
- Lina Meinecke
- Department of Mathematics, University of California, Irvine, CA, United States of America
- Center for Complex Biological Systems, University of California, Irvine, CA, United States of America
| | - Praveer P. Sharma
- Center for Complex Biological Systems, University of California, Irvine, CA, United States of America
- Department of Developmental and Cell Biology, University of California, Irvine, CA, United States of America
| | - Huijing Du
- Department of Mathematics, University of Nebraska, Lincoln, NE, United States of America
| | - Lei Zhang
- Beijing International Center for Mathematical Research, Peking University, Beijing, China
- Center for Quantitative Biology, Peking University, Beijing, China
| | - Qing Nie
- Department of Mathematics, University of California, Irvine, CA, United States of America
- Center for Complex Biological Systems, University of California, Irvine, CA, United States of America
- Department of Developmental and Cell Biology, University of California, Irvine, CA, United States of America
| | - Thomas F. Schilling
- Center for Complex Biological Systems, University of California, Irvine, CA, United States of America
- Department of Developmental and Cell Biology, University of California, Irvine, CA, United States of America
| |
Collapse
|
56
|
Jin S, O J, Stellabotte F, Choe CP. Foxi1 promotes late-stage pharyngeal pouch morphogenesis through ectodermal Wnt4a activation. Dev Biol 2018; 441:12-18. [PMID: 29932895 DOI: 10.1016/j.ydbio.2018.06.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 06/08/2018] [Accepted: 06/18/2018] [Indexed: 11/26/2022]
Abstract
The pharyngeal pouches are a series of epithelial outgrowths of the foregut endoderm. Pharyngeal pouches segment precursors of the vertebrate face into pharyngeal arches and pattern the facial skeleton. These pouches fail to develop normally in zebrafish foxi1 mutants, yet the role Foxi1 plays in pouch development remains to be determined. Here we show that ectodermal Foxi1 acts downstream of Fgf8a during the late stage of pouch development to promote rearrangement of pouch-forming cells into bilayers. During this phase, foxi1 and wnt4a are coexpressed in the facial ectoderm and their expression is expanded in fgf8a mutants. foxi1 expression is unaffected in wnt4a mutants; conversely, ectodermal wnt4a expression is abolished in foxi1 mutants. Consistent with this, foxi1 mutant pouch and facial skeletal defects resemble those of wnt4a mutants. These findings suggest that ectodermal Foxi1 mediates late-stage pouch morphogenesis through wnt4a expression. We therefore propose that Fox1 activation of Wnt4a in the ectoderm signals the epithelial stabilization of pouch-forming cells during late-stage of pouch morphogenesis.
Collapse
Affiliation(s)
- Sil Jin
- Division of Applied Life Science (BK21 Plus Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Jiyun O
- Division of Life Science, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Frank Stellabotte
- School of Allied Health, Business, and STEM, Middlesex Community College, Middletown, CT 06457, USA
| | - Chong Pyo Choe
- Division of Applied Life Science (BK21 Plus Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 52828, Republic of Korea; Division of Life Science, Gyeongsang National University, Jinju 52828, Republic of Korea.
| |
Collapse
|
57
|
Schneider RA. Neural crest and the origin of species-specific pattern. Genesis 2018; 56:e23219. [PMID: 30134069 PMCID: PMC6108449 DOI: 10.1002/dvg.23219] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 05/15/2018] [Accepted: 05/16/2018] [Indexed: 12/20/2022]
Abstract
For well over half of the 150 years since the discovery of the neural crest, the special ability of these cells to function as a source of species-specific pattern has been clearly recognized. Initially, this observation arose in association with chimeric transplant experiments among differentially pigmented amphibians, where the neural crest origin for melanocytes had been duly noted. Shortly thereafter, the role of cranial neural crest cells in transmitting species-specific information on size and shape to the pharyngeal arch skeleton as well as in regulating the timing of its differentiation became readily apparent. Since then, what has emerged is a deeper understanding of how the neural crest accomplishes such a presumably difficult mission, and this includes a more complete picture of the molecular and cellular programs whereby neural crest shapes the face of each species. This review covers studies on a broad range of vertebrates and describes neural-crest-mediated mechanisms that endow the craniofacial complex with species-specific pattern. A major focus is on experiments in quail and duck embryos that reveal a hierarchy of cell-autonomous and non-autonomous signaling interactions through which neural crest generates species-specific pattern in the craniofacial integument, skeleton, and musculature. By controlling size and shape throughout the development of these systems, the neural crest underlies the structural and functional integration of the craniofacial complex during evolution.
Collapse
Affiliation(s)
- Richard A. Schneider
- Department of Orthopedic SurgeryUniversity of California at San Francisco, 513 Parnassus AvenueS‐1161San Francisco, California
| |
Collapse
|
58
|
Kameda Y. Morphological and molecular evolution of the ultimobranchial gland of nonmammalian vertebrates, with special reference to the chicken C cells. Dev Dyn 2017; 246:719-739. [PMID: 28608500 DOI: 10.1002/dvdy.24534] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 04/30/2017] [Accepted: 04/30/2017] [Indexed: 12/14/2022] Open
Abstract
This review summarizes the current understanding of the nonmammalian ultimobranchial gland from morphological and molecular perspectives. Ultimobranchial anlage of all animal species develops from the last pharyngeal pouch. The genes involved in the development of pharyngeal pouches are well conserved across vertebrates. The ultimobranchial anlage of nonmammalian vertebrates and monotremes does not merge with the thyroid, remaining as an independent organ throughout adulthood. Although C cells of all animal species secrete calcitonin, the shape, cellular components and location of the ultimobranchial gland vary from species to species. Avian ultimobranchial gland is unique in several phylogenic aspects; the organ is located between the vagus and recurrent laryngeal nerves at the upper thorax and is densely innervated by branches emanating from them. In chick embryos, TuJ1-, HNK-1-, and PGP 9.5-immunoreactive cells that originate from the distal vagal (nodose) ganglion, colonize the ultimobranchial anlage and differentiate into C cells; neuronal cells give rise to C cells. Like C cells of mammals, the cells of fishes, amphibians, reptiles, and also a subset of C cells of birds, appear to be derived from the endodermal epithelium forming ultimobranchial anlage. Thus, the avian ultimobranchial C cells may have dual origins, neural progenitors and endodermal epithelium. Developmental Dynamics 246:719-739, 2017. © 2017 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Yoko Kameda
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| |
Collapse
|
59
|
Square T, Jandzik D, Romášek M, Cerny R, Medeiros DM. The origin and diversification of the developmental mechanisms that pattern the vertebrate head skeleton. Dev Biol 2017; 427:219-229. [DOI: 10.1016/j.ydbio.2016.11.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/06/2016] [Accepted: 11/20/2016] [Indexed: 01/30/2023]
|
60
|
Chen J, Jacox LA, Saldanha F, Sive H. Mouth development. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2017; 6. [PMID: 28514120 PMCID: PMC5574021 DOI: 10.1002/wdev.275] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 03/28/2017] [Accepted: 04/03/2017] [Indexed: 12/12/2022]
Abstract
A mouth is present in all animals, and comprises an opening from the outside into the oral cavity and the beginnings of the digestive tract to allow eating. This review focuses on the earliest steps in mouth formation. In the first half, we conclude that the mouth arose once during evolution. In all animals, the mouth forms from ectoderm and endoderm. A direct association of oral ectoderm and digestive endoderm is present even in triploblastic animals, and in chordates, this region is known as the extreme anterior domain (EAD). Further support for a single origin of the mouth is a conserved set of genes that form a 'mouth gene program' including foxA and otx2. In the second half of this review, we discuss steps involved in vertebrate mouth formation, using the frog Xenopus as a model. The vertebrate mouth derives from oral ectoderm from the anterior neural ridge, pharyngeal endoderm and cranial neural crest (NC). Vertebrates form a mouth by breaking through the body covering in a precise sequence including specification of EAD ectoderm and endoderm as well as NC, formation of a 'pre-mouth array,' basement membrane dissolution, stomodeum formation, and buccopharyngeal membrane perforation. In Xenopus, the EAD is also a craniofacial organizer that guides NC, while reciprocally, the NC signals to the EAD to elicit its morphogenesis into a pre-mouth array. Human mouth anomalies are prevalent and are affected by genetic and environmental factors, with understanding guided in part by use of animal models. WIREs Dev Biol 2017, 6:e275. doi: 10.1002/wdev.275 For further resources related to this article, please visit the WIREs website.
Collapse
Affiliation(s)
- Justin Chen
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA.,Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Laura A Jacox
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA.,Harvard-MIT Health Sciences and Technology Program, Cambridge, MA, USA.,Harvard School of Dental Medicine, Boston, MA, USA
| | | | - Hazel Sive
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA.,Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| |
Collapse
|
61
|
Alvarado E, Yousefelahiyeh M, Alvarado G, Shang R, Whitman T, Martinez A, Yu Y, Pham A, Bhandari A, Wang B, Nissen RM. Wdr68 Mediates Dorsal and Ventral Patterning Events for Craniofacial Development. PLoS One 2016; 11:e0166984. [PMID: 27880803 PMCID: PMC5120840 DOI: 10.1371/journal.pone.0166984] [Citation(s) in RCA: 16] [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: 05/26/2016] [Accepted: 11/07/2016] [Indexed: 12/15/2022] Open
Abstract
Birth defects are among the leading causes of infant mortality and contribute substantially to illness and long-term disability. Defects in Bone Morphogenetic Protein (BMP) signaling are associated with cleft lip/palate. Many craniofacial syndromes are caused by defects in signaling pathways that pattern the cranial neural crest cells (CNCCs) along the dorsal-ventral axis. For example, auriculocondylar syndrome is caused by impaired Endothelin-1 (Edn1) signaling, and Alagille syndrome is caused by defects in Jagged-Notch signaling. The BMP, Edn1, and Jag1b pathways intersect because BMP signaling is required for ventral edn1 expression that, in turn, restricts jag1b to dorsal CNCC territory. In zebrafish, the scaffolding protein Wdr68 is required for edn1 expression and subsequent formation of the ventral Meckel’s cartilage as well as the dorsal Palatoquadrate. Here we report that wdr68 activity is required between the 17-somites and prim-5 stages, that edn1 functions downstream of wdr68, and that wdr68 activity restricts jag1b, hey1, and grem2 expression from ventral CNCC territory. Expression of dlx1a and dlx2a was also severely reduced in anterior dorsal and ventral 1st arch CNCC territory in wdr68 mutants. We also found that the BMP agonist isoliquiritigenin (ISL) can partially rescue lower jaw formation and edn1 expression in wdr68 mutants. However, we found no significant defects in BMP reporter induction or pSmad1/5 accumulation in wdr68 mutant cells or zebrafish. The Transforming Growth Factor Beta (TGF-β) signaling pathway is also known to be important for craniofacial development and can interfere with BMP signaling. Here we further report that TGF-β interference with BMP signaling was greater in wdr68 mutant cells relative to control cells. To determine whether interference might also act in vivo, we treated wdr68 mutant zebrafish embryos with the TGF-β signaling inhibitor SB431542 and found partial rescue of edn1 expression and craniofacial development. While ISL treatment failed, SB431542 partially rescued dlx2a expression in wdr68 mutants. Together these findings reveal an indirect role for Wdr68 in the BMP-Edn1-Jag1b signaling hierarchy and dorso-anterior expression of dlx1a/2a.
Collapse
Affiliation(s)
- Estibaliz Alvarado
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, United States of America
| | - Mina Yousefelahiyeh
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, United States of America
| | - Greg Alvarado
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, United States of America
| | - Robin Shang
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, United States of America
| | - Taryn Whitman
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, United States of America
| | - Andrew Martinez
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, United States of America
| | - Yang Yu
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, United States of America
| | - Annie Pham
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, United States of America
| | - Anish Bhandari
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, United States of America
| | - Bingyan Wang
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, United States of America
| | - Robert M. Nissen
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, United States of America
- * E-mail:
| |
Collapse
|
62
|
Ahi EP. Signalling pathways in trophic skeletal development and morphogenesis: Insights from studies on teleost fish. Dev Biol 2016; 420:11-31. [PMID: 27713057 DOI: 10.1016/j.ydbio.2016.10.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 10/02/2016] [Accepted: 10/03/2016] [Indexed: 12/12/2022]
Abstract
During the development of the vertebrate feeding apparatus, a variety of complicated cellular and molecular processes participate in the formation and integration of individual skeletal elements. The molecular mechanisms regulating the formation of skeletal primordia and their development into specific morphological structures are tightly controlled by a set of interconnected signalling pathways. Some of these pathways, such as Bmp, Hedgehog, Notch and Wnt, are long known for their pivotal roles in craniofacial skeletogenesis. Studies addressing the functional details of their components and downstream targets, the mechanisms of their interactions with other signals as well as their potential roles in adaptive morphological divergence, are currently attracting considerable attention. An increasing number of signalling pathways that had previously been described in different biological contexts have been shown to be important in the regulation of jaw skeletal development and morphogenesis. In this review, I provide an overview of signalling pathways involved in trophic skeletogenesis emphasizing studies of the most species-rich group of vertebrates, the teleost fish, which through their evolutionary history have undergone repeated episodes of spectacular trophic diversification.
Collapse
Affiliation(s)
- Ehsan Pashay Ahi
- Institute of Zoology, University of Graz, Universitätsplatz 2, A-8010 Graz, Austria; Institute of Life and Environmental Sciences, University of Iceland, Sturlugata 7, 101 Reykjavik, Iceland.
| |
Collapse
|
63
|
Talbot JC, Nichols JT, Yan YL, Leonard IF, BreMiller RA, Amacher SL, Postlethwait JH, Kimmel CB. Pharyngeal morphogenesis requires fras1-itga8-dependent epithelial-mesenchymal interaction. Dev Biol 2016; 416:136-148. [PMID: 27265864 PMCID: PMC4967372 DOI: 10.1016/j.ydbio.2016.05.035] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 05/31/2016] [Indexed: 01/08/2023]
Abstract
Both Fras1 and Itga8 connect mesenchymal cells to epithelia by way of an extracellular 'Fraser protein complex' that functions in signaling and adhesion; these proteins are vital to the development of several vertebrate organs. We previously found that zebrafish fras1 mutants have craniofacial defects, specifically, shortened symplectic cartilages and cartilage fusions that spare joint elements. During a forward mutagenesis screen, we identified a new zebrafish mutation, b1161, that we show here disrupts itga8, as confirmed using CRISPR-generated itga8 alleles. fras1 and itga8 single mutants and double mutants have similar craniofacial phenotypes, a result expected if loss of either gene disrupts function of the Fraser protein complex. Unlike fras1 mutants or other Fraser-related mutants, itga8 mutants do not show blistered tail fins. Thus, the function of the Fraser complex differs in the craniofacial skeleton and the tail fin. Focusing on the face, we find that itga8 mutants consistently show defective outpocketing of a late-forming portion of the first pharyngeal pouch, and variably express skeletal defects, matching previously characterized fras1 mutant phenotypes. In itga8 and fras1 mutants, skeletal severity varies markedly between sides, indicating that both mutants have increased developmental instability. Whereas fras1 is expressed in epithelia, we show that itga8 is expressed complementarily in facial mesenchyme. Paired with the observed phenotypic similarity, this expression indicates that the genes function in epithelial-mesenchymal interactions. Similar interactions between Fras1 and Itga8 have previously been found in mouse kidney, where these genes both regulate Nephronectin (Npnt) protein abundance. We find that zebrafish facial tissues express both npnt and the Fraser gene fibrillin2b (fbn2b), but their transcript levels do not depend on fras1 or itga8 function. Using a revertible fras1 allele, we find that the critical window for fras1 function in the craniofacial skeleton is between 1.5 and 3 days post fertilization, which coincides with the onset of fras1-dependent and itga8-dependent morphogenesis. We propose a model wherein Fras1 and Itga8 interact during late pharyngeal pouch morphogenesis to sculpt pharyngeal arches through epithelial-mesenchymal interactions, thereby stabilizing the developing craniofacial skeleton.
Collapse
Affiliation(s)
- Jared Coffin Talbot
- Institute of Neuroscience, 1254 University of Oregon, Eugene, OR 97403, USA; Departments of Molecular Genetics and Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH 43210, USA.
| | - James T Nichols
- Institute of Neuroscience, 1254 University of Oregon, Eugene, OR 97403, USA
| | - Yi-Lin Yan
- Institute of Neuroscience, 1254 University of Oregon, Eugene, OR 97403, USA
| | - Isaac F Leonard
- Institute of Neuroscience, 1254 University of Oregon, Eugene, OR 97403, USA
| | - Ruth A BreMiller
- Institute of Neuroscience, 1254 University of Oregon, Eugene, OR 97403, USA
| | - Sharon L Amacher
- Departments of Molecular Genetics and Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH 43210, USA
| | | | - Charles B Kimmel
- Institute of Neuroscience, 1254 University of Oregon, Eugene, OR 97403, USA.
| |
Collapse
|
64
|
Miyashita T, Diogo R. Evolution of Serial Patterns in the Vertebrate Pharyngeal Apparatus and Paired Appendages via Assimilation of Dissimilar Units. Front Ecol Evol 2016. [DOI: 10.3389/fevo.2016.00071] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
|
65
|
Lovely CB, Swartz ME, McCarthy N, Norrie JL, Eberhart JK. Bmp signaling mediates endoderm pouch morphogenesis by regulating Fgf signaling in zebrafish. Development 2016; 143:2000-11. [PMID: 27122171 DOI: 10.1242/dev.129379] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 04/12/2016] [Indexed: 02/03/2023]
Abstract
The endodermal pouches are a series of reiterated structures that segment the pharyngeal arches and help pattern the vertebrate face. Multiple pathways regulate the complex process of endodermal development, including the Bone morphogenetic protein (Bmp) pathway. However, the role of Bmp signaling in pouch morphogenesis is poorly understood. Using genetic and chemical inhibitor approaches, we show that pouch morphogenesis requires Bmp signaling from 10-18 h post-fertilization, immediately following gastrulation. Blocking Bmp signaling during this window results in morphological defects to the pouches and craniofacial skeleton. Using genetic chimeras we show that Bmp signals directly to the endoderm for proper morphogenesis. Time-lapse imaging and analysis of reporter transgenics show that Bmp signaling is necessary for pouch outpocketing via the Fibroblast growth factor (Fgf) pathway. Double loss-of-function analyses demonstrate that Bmp and Fgf signaling interact synergistically in craniofacial development. Collectively, our analyses shed light on the tissue and signaling interactions that regulate development of the vertebrate face.
Collapse
Affiliation(s)
- C Ben Lovely
- Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Mary E Swartz
- Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Neil McCarthy
- Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | | | - Johann K Eberhart
- Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| |
Collapse
|
66
|
Dye BR, Miller AJ, Spence JR. How to Grow a Lung: Applying Principles of Developmental Biology to Generate Lung Lineages from Human Pluripotent Stem Cells. CURRENT PATHOBIOLOGY REPORTS 2016; 4:47-57. [PMID: 27340610 PMCID: PMC4882378 DOI: 10.1007/s40139-016-0102-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The number and severity of diseases affecting human lung development and adult respiratory function has stimulated great interest in new in vitro models to study the human lung. This review summarizes the most recent breakthroughs deriving lung lineages in a dish by directing the differentiation of human pluripotent stem cells. A variety of culturing platforms have been developed, including two-dimensional and three-dimensional (organoid) culture platforms, to derive specific cell types and structures of the lung. These stem cell-derived lung models will further our understanding of human lung development, disease, and regeneration.
Collapse
Affiliation(s)
- Briana R. Dye
- />Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan 48109 USA
| | - Alyssa J. Miller
- />Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan 48109 USA
- />Department of Cell and Molecular Biology, University of Michigan Medical School, Ann Arbor, Michigan 48109 USA
| | - Jason R. Spence
- />Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan 48109 USA
- />Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan 48109 USA
- />Department of Cell and Molecular Biology, University of Michigan Medical School, Ann Arbor, Michigan 48109 USA
- />Center for Organogenesis, University of Michigan Medical School, Ann Arbor, Michigan 48109 USA
| |
Collapse
|
67
|
Competition between Jagged-Notch and Endothelin1 Signaling Selectively Restricts Cartilage Formation in the Zebrafish Upper Face. PLoS Genet 2016; 12:e1005967. [PMID: 27058748 PMCID: PMC4825933 DOI: 10.1371/journal.pgen.1005967] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 03/09/2016] [Indexed: 11/25/2022] Open
Abstract
The intricate shaping of the facial skeleton is essential for function of the vertebrate jaw and middle ear. While much has been learned about the signaling pathways and transcription factors that control facial patterning, the downstream cellular mechanisms dictating skeletal shapes have remained unclear. Here we present genetic evidence in zebrafish that three major signaling pathways − Jagged-Notch, Endothelin1 (Edn1), and Bmp − regulate the pattern of facial cartilage and bone formation by controlling the timing of cartilage differentiation along the dorsoventral axis of the pharyngeal arches. A genomic analysis of purified facial skeletal precursors in mutant and overexpression embryos revealed a core set of differentiation genes that were commonly repressed by Jagged-Notch and induced by Edn1. Further analysis of the pre-cartilage condensation gene barx1, as well as in vivo imaging of cartilage differentiation, revealed that cartilage forms first in regions of high Edn1 and low Jagged-Notch activity. Consistent with a role of Jagged-Notch signaling in restricting cartilage differentiation, loss of Notch pathway components resulted in expanded barx1 expression in the dorsal arches, with mutation of barx1 rescuing some aspects of dorsal skeletal patterning in jag1b mutants. We also identified prrx1a and prrx1b as negative Edn1 and positive Bmp targets that function in parallel to Jagged-Notch signaling to restrict the formation of dorsal barx1+ pre-cartilage condensations. Simultaneous loss of jag1b and prrx1a/b better rescued lower facial defects of edn1 mutants than loss of either pathway alone, showing that combined overactivation of Jagged-Notch and Bmp/Prrx1 pathways contribute to the absence of cartilage differentiation in the edn1 mutant lower face. These findings support a model in which Notch-mediated restriction of cartilage differentiation, particularly in the second pharyngeal arch, helps to establish a distinct skeletal pattern in the upper face. The exquisite functions of the vertebrate face require the precise formation of its underlying bones. Remarkably, many of the genes required to shape the facial skeleton are the same from fish to man. In this study, we use the powerful zebrafish system to understand how the skeletal components of the face acquire different shapes during development. To do so, we analyze a series of mutants that disrupt patterning of the facial skeleton, and then assess how the genes affected in these mutants control cell fate in skeletal progenitor cells. From these genetic studies, we found that several pathways converge to control when and where progenitor cells commit to a cartilage fate, thus controlling the size and shape of cartilage templates for the later-arising bones. Our work thus reveals how regulating the timing of when progenitor cells make skeleton helps to shape the bones of the zebrafish face. As mutations in many of the genes studied are implicated in human craniofacial defects, differences in the timing of progenitor cell differentiation may also explain the wonderful diversity of human faces.
Collapse
|
68
|
McCarthy N, Sidik A, Bertrand JY, Eberhart JK. An Fgf-Shh signaling hierarchy regulates early specification of the zebrafish skull. Dev Biol 2016; 415:261-277. [PMID: 27060628 PMCID: PMC4967541 DOI: 10.1016/j.ydbio.2016.04.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 03/30/2016] [Accepted: 04/05/2016] [Indexed: 02/03/2023]
Abstract
The neurocranium generates most of the craniofacial skeleton and consists of prechordal and postchordal regions. Although development of the prechordal is well studied, little is known of the postchordal region. Here we characterize a signaling hierarchy necessary for postchordal neurocranial development involving Fibroblast growth factor (Fgf) signaling for early specification of mesodermally-derived progenitor cells. The expression of hyaluron synthetase 2 (has2) in the cephalic mesoderm requires Fgf signaling and Has2 function, in turn, is required for postchordal neurocranial development. While Hedgehog (Hh)-deficient embryos also lack a postchordal neurocranium, this appears primarily due to a later defect in chondrocyte differentiation. Inhibitor studies demonstrate that postchordal neurocranial development requires early Fgf and later Hh signaling. Collectively, our results provide a mechanistic understanding of early postchordal neurocranial development and demonstrate a hierarchy of signaling between Fgf and Hh in the development of this structure.
Collapse
Affiliation(s)
- Neil McCarthy
- Department of Molecular Biosciences; Institute of Cell and Molecular Biology, Waggoner Center for Alcohol and Alcohol Addiction Research, University of Texas, Austin, TX, United States
| | - Alfire Sidik
- Department of Molecular Biosciences; Institute of Cell and Molecular Biology, Waggoner Center for Alcohol and Alcohol Addiction Research, University of Texas, Austin, TX, United States
| | - Julien Y Bertrand
- Department of Pathology and Immunology, University of Geneva Medical School, Geneva, Switzerland
| | - Johann K Eberhart
- Department of Molecular Biosciences; Institute of Cell and Molecular Biology, Waggoner Center for Alcohol and Alcohol Addiction Research, University of Texas, Austin, TX, United States; Department of Molecular Biosciences; Institute of Neurobiology, University of Texas, Austin, TX, United States.
| |
Collapse
|
69
|
Okada K, Inohaya K, Mise T, Kudo A, Takada S, Wada H. Reiterative expression of pax1 directs pharyngeal pouch segmentation in medaka (Oryzias latipes). Development 2016; 143:1800-10. [DOI: 10.1242/dev.130039] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 03/21/2016] [Indexed: 12/27/2022]
Abstract
A striking characteristic of vertebrate development is the pharyngeal arches, which are a series of bulges on the lateral surface of the head of vertebrate embryos. Although each pharyngeal arch is segmented by the reiterative formation of endodermal outpocketings called pharyngeal pouches, the molecular network underlying the reiterative pattern remains unclear. Here, we show that pax1 plays critical roles in pouch segmentation in medaka embryos. Importantly, pax1 expression in the endoderm prefigures the location of the next pouch before the cells bud from the epithelium. TALEN-generated pax1 mutants did not form pharyngeal pouches posterior to the second arch. Segmental expression of tbx1 and fgf3, which play critical roles in pouch development, was almost nonexistent in the pharyngeal endoderm of pax1 mutants, with disturbance of the reiterative pattern of pax1 expression. These results suggest that pax1 plays a critical role in generating the primary pattern for segmentation in the pharyngeal endoderm by regulating tbx1 and fgf3 expression. Our findings illustrate the critical roles of pax1 in vertebrate pharyngeal segmentation and provide insights into the evolutionary origin of the deuterostome gill slit.
Collapse
Affiliation(s)
- Kazunori Okada
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 111 Tennoudai, Tsukuba, 305-8572, Japan
- Okazaki Institute for Integrative Bioscience and National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, 444-8787, Japan
| | - Keiji Inohaya
- Department of Biological Information, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8501, Japan
| | - Takeshi Mise
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 111 Tennoudai, Tsukuba, 305-8572, Japan
| | - Akira Kudo
- Department of Biological Information, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8501, Japan
| | - Shinji Takada
- Okazaki Institute for Integrative Bioscience and National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, 444-8787, Japan
- Department for Basic Biology, SOKENDAI (The Graduate University for Advanced Studies), 5-1 Higashiyama, Myodaiji-cho, Okazaki, 444-8787, Japan
| | - Hiroshi Wada
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 111 Tennoudai, Tsukuba, 305-8572, Japan
| |
Collapse
|
70
|
Square T, Romášek M, Jandzik D, Cattell MV, Klymkowsky M, Medeiros DM. CRISPR/Cas9-mediated mutagenesis in the sea lamprey Petromyzon marinus: a powerful tool for understanding ancestral gene functions in vertebrates. DEVELOPMENT (CAMBRIDGE, ENGLAND) 2015. [PMID: 26511928 DOI: 10.1242/dev.125609.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Lamprey is one of only two living jawless vertebrates, a group that includes the first vertebrates. Comparisons between lamprey and jawed vertebrates have yielded important insights into the origin and evolution of vertebrate physiology, morphology and development. Despite its key phylogenetic position, studies of lamprey have been limited by their complex life history, which makes traditional genetic approaches impossible. The CRISPR/Cas9 system is a bacterial defense mechanism that was recently adapted to achieve high-efficiency targeted mutagenesis in eukaryotes. Here we report CRISPR/Cas9-mediated disruption of the genes Tyrosinase and FGF8/17/18 in the sea lamprey Petromyzon marinus, and detail optimized parameters for producing mutant F0 embryos. Using phenotype and genotype analyses, we show that CRISPR/Cas9 is highly effective in the sea lamprey, with a majority of injected embryos developing into complete or partial mutants. The ability to create large numbers of mutant embryos without inbred lines opens exciting new possibilities for studying development in lamprey and other non-traditional model organisms with life histories that prohibit the generation of mutant lines.
Collapse
Affiliation(s)
- Tyler Square
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO 80309, USA
| | - Marek Romášek
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO 80309, USA
| | - David Jandzik
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO 80309, USA Department of Zoology, Comenius University in Bratislava, Bratislava 84215, Slovakia
| | - Maria V Cattell
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO 80309, USA Department of Pediatrics, University of Colorado, Denver, Aurora, CO 80045, USA
| | - Michael Klymkowsky
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Boulder, CO 80309, USA
| | - Daniel M Medeiros
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO 80309, USA
| |
Collapse
|
71
|
Square T, Romášek M, Jandzik D, Cattell MV, Klymkowsky M, Medeiros DM. CRISPR/Cas9-mediated mutagenesis in the sea lamprey Petromyzon marinus: a powerful tool for understanding ancestral gene functions in vertebrates. Development 2015; 142:4180-7. [PMID: 26511928 DOI: 10.1242/dev.125609] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 10/19/2015] [Indexed: 12/24/2022]
Abstract
Lamprey is one of only two living jawless vertebrates, a group that includes the first vertebrates. Comparisons between lamprey and jawed vertebrates have yielded important insights into the origin and evolution of vertebrate physiology, morphology and development. Despite its key phylogenetic position, studies of lamprey have been limited by their complex life history, which makes traditional genetic approaches impossible. The CRISPR/Cas9 system is a bacterial defense mechanism that was recently adapted to achieve high-efficiency targeted mutagenesis in eukaryotes. Here we report CRISPR/Cas9-mediated disruption of the genes Tyrosinase and FGF8/17/18 in the sea lamprey Petromyzon marinus, and detail optimized parameters for producing mutant F0 embryos. Using phenotype and genotype analyses, we show that CRISPR/Cas9 is highly effective in the sea lamprey, with a majority of injected embryos developing into complete or partial mutants. The ability to create large numbers of mutant embryos without inbred lines opens exciting new possibilities for studying development in lamprey and other non-traditional model organisms with life histories that prohibit the generation of mutant lines.
Collapse
Affiliation(s)
- Tyler Square
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO 80309, USA
| | - Marek Romášek
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO 80309, USA
| | - David Jandzik
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO 80309, USA Department of Zoology, Comenius University in Bratislava, Bratislava 84215, Slovakia
| | - Maria V Cattell
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO 80309, USA Department of Pediatrics, University of Colorado, Denver, Aurora, CO 80045, USA
| | - Michael Klymkowsky
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Boulder, CO 80309, USA
| | - Daniel M Medeiros
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO 80309, USA
| |
Collapse
|
72
|
Abstract
Molecular and cellular mechanisms that control jaw length are becoming better understood. This is significant since the jaws are not only critical for species-specific adaptation and survival, but they are often affected by a variety of size-related anomalies including mandibular hypoplasia, retrognathia, asymmetry, and clefting. This chapter overviews how jaw length is established during the allocation, proliferation, differentiation, and growth of jaw precursor cells, which originate from neural crest mesenchyme (NCM). The focus is mainly on results from experiments transplanting NCM between quail and duck embryos. Quail have short jaws whereas those of duck are relatively long. Quail-duck chimeras reveal that the determinants of jaw length are NCM mediated throughout development and include species-specific differences in jaw progenitor number, differential regulation of various signaling pathways, and the autonomous activation of programs for skeletal matrix deposition and resorption. Such insights help make the goal of devising new therapies for birth defects, diseases, and injuries to the jaw skeleton seem ever more likely.
Collapse
Affiliation(s)
- Richard A Schneider
- Department of Orthopaedic Surgery, University of California at San Francisco, San Francisco, California, USA.
| |
Collapse
|
73
|
Miyashita T. Fishing for jaws in early vertebrate evolution: a new hypothesis of mandibular confinement. Biol Rev Camb Philos Soc 2015; 91:611-57. [DOI: 10.1111/brv.12187] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 03/18/2015] [Accepted: 03/19/2015] [Indexed: 12/21/2022]
Affiliation(s)
- Tetsuto Miyashita
- Department of Biological Sciences; University of Alberta; Edmonton Alberta T6G 2E9 Canada
| |
Collapse
|
74
|
Choe CP, Crump JG. Dynamic epithelia of the developing vertebrate face. Curr Opin Genet Dev 2015; 32:66-72. [PMID: 25748249 DOI: 10.1016/j.gde.2015.02.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 01/29/2015] [Accepted: 02/01/2015] [Indexed: 10/23/2022]
Abstract
A segmental series of endoderm-derived pouch and ectoderm-derived cleft epithelia act as signaling centers in the developing face. Their precise morphogenesis is therefore essential for proper patterning of the vertebrate head. Intercellular adhesion and polarity are highly dynamic within developing facial epithelial cells, with signaling from the adjacent mesenchyme controlling both epithelial character and directional migration. Endodermal and ectodermal epithelia fuse to form the primary mouth and gill slits, which involves basement membrane dissolution, cell intercalations, and apoptosis, as well as undergo further morphogenesis to generate the middle ear cavity and glands of the neck. Recent studies of facial epithelia are revealing both core programs of epithelial morphogenesis and insights into the coordinated assembly of the vertebrate head.
Collapse
Affiliation(s)
- Chong Pyo Choe
- Broad California Institute of Regenerative Medicine Center, Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - J Gage Crump
- Broad California Institute of Regenerative Medicine Center, Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
| |
Collapse
|
75
|
Choe CP, Crump JG. Eph-Pak2a signaling regulates branching of the pharyngeal endoderm by inhibiting late-stage epithelial dynamics. Development 2015; 142:1089-94. [PMID: 25725065 DOI: 10.1242/dev.115774] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Branching morphogenesis depends on the precise temporal and spatial control of epithelial dynamics. In the vertebrate head, endodermal branches, called pharyngeal pouches, form through the transient stratification, collective migration and reorganization of epithelial cells into bilayers. Here, we report novel requirements for the EphrinB ligands B2a and B3b, the Ephb4a receptor and the Pak2a kinase in the development of pouches and the posterior facial skeleton that depends on pouches for its segmentation. Time-lapse imaging in zebrafish shows that EphB-Pak2a signaling is required to stabilize pouch epithelial cells at the end of branching morphogenesis. Transgenic rescue experiments further demonstrate that endodermal Eph-ephrin signaling promotes pouch integrity by targeting Pak2a to the plasma membrane, where subsequent activation by Wnt4a-Cdc42 signaling increases junctional E-cadherin in maturing pouches. Integration of Eph-ephrin and Wnt4a signaling through Pak2a thus signals the end of branching morphogenesis by increasing intercellular adhesion that blocks further epithelial rearrangements.
Collapse
Affiliation(s)
- Chong Pyo Choe
- Broad CIRM Center, Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - J Gage Crump
- Broad CIRM Center, Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| |
Collapse
|
76
|
Frisdal A, Trainor PA. Development and evolution of the pharyngeal apparatus. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2014; 3:403-18. [PMID: 25176500 DOI: 10.1002/wdev.147] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 05/19/2014] [Accepted: 06/10/2014] [Indexed: 01/06/2023]
Abstract
The oral or pharyngeal apparatus facilitates the dual functions of respiration and feeding. It develops during embryogenesis from transient structures called pharyngeal arches (PAs), which comprise a reiterated series of outgrowths on the lateral side of the head. The PAs and their segmental arrangement are highly conserved throughout evolution from invertebrate chordates such as amphioxus, through to vertebrate agnathans including avians, squamates, and mammals. The structural organization of the PAs is also highly conserved and involves contributions from each of the three primary endoderm, mesoderm, and ectoderm germ layers. The endoderm is particularly important for PA formation and segmentation and also plays a critical role in tissue-specific differentiation. The ectoderm gives rise to neural crest cells (NCC) which provide an additional layer of complexity to PA development and differentiation in vertebrates compared to invertebrate chordates that do not possess NCC. Collectively, the PAs give rise to much of the neurovasculature and musculoskeletal systems in the head and neck. The complexity of development renders the pharyngeal apparatus prone to perturbation and subsequently the pathogenesis of birth defects. Hence it is important to understand the signals and mechanisms that govern the development and evolution of the pharyngeal complex.
Collapse
Affiliation(s)
- Aude Frisdal
- Stowers Institute for Medical Research, Kansas City, MO, USA; University Pierre and Marie Curie, Paris, France
| | | |
Collapse
|
77
|
Choe CP, Crump JG. Tbx1 controls the morphogenesis of pharyngeal pouch epithelia through mesodermal Wnt11r and Fgf8a. Development 2014; 141:3583-93. [PMID: 25142463 PMCID: PMC4197720 DOI: 10.1242/dev.111740] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The pharyngeal pouches are a segmental series of epithelial structures that organize the embryonic vertebrate face. In mice and zebrafish that carry mutations in homologs of the DiGeorge syndrome gene TBX1, a lack of pouches correlates with severe craniofacial defects, yet how Tbx1 controls pouch development remains unclear. Using mutant and transgenic rescue experiments in zebrafish, we show that Tbx1 functions in the mesoderm to promote the morphogenesis of pouch-forming endoderm through wnt11r and fgf8a expression. Consistently, compound losses of wnt11r and fgf8a phenocopy tbx1 mutant pouch defects, and mesoderm-specific restoration of Wnt11r and Fgf8a rescues tbx1 mutant pouches. Time-lapse imaging further reveals that Fgf8a acts as a Wnt11r-dependent guidance cue for migrating pouch cells. We therefore propose a two-step model in which Tbx1 coordinates the Wnt-dependent epithelial destabilization of pouch-forming cells with their collective migration towards Fgf8a-expressing mesodermal guideposts.
Collapse
Affiliation(s)
- Chong Pyo Choe
- Broad California Institute of Regenerative Medicine Center, Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - J Gage Crump
- Broad California Institute of Regenerative Medicine Center, Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| |
Collapse
|
78
|
Graham A, Butts T, Lumsden A, Kiecker C. What can vertebrates tell us about segmentation? EvoDevo 2014; 5:24. [PMID: 25009737 PMCID: PMC4088296 DOI: 10.1186/2041-9139-5-24] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 06/11/2014] [Indexed: 12/28/2022] Open
Abstract
Segmentation is a feature of the body plans of a number of diverse animal groupings, including the annelids, arthropods and chordates. However, it has been unclear whether or not these different manifestations of segmentation are independently derived or have a common origin. Central to this issue is whether or not there are common developmental mechanisms that establish segmentation and the evolutionary origins of these processes. A fruitful way to address this issue is to consider how segmentation in vertebrates is directed. During vertebrate development three different segmental systems are established: the somites, the rhombomeres and the pharyngeal arches. In each an iteration of parts along the long axis is established. However, it is clear that the formation of the somites, rhombomeres or pharyngeal arches have little in common, and as such there is no single segmentation process. These different segmental systems also have distinct evolutionary histories, thus highlighting the fact that segmentation can and does evolve independently at multiple points. We conclude that the term segmentation indicates nothing more than a morphological description and that it implies no mechanistic similarity. Thus it is probable that segmentation has arisen repeatedly during animal evolution.
Collapse
Affiliation(s)
- Anthony Graham
- MRC Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK
| | - Thomas Butts
- MRC Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK
| | - Andrew Lumsden
- MRC Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK
| | - Clemens Kiecker
- MRC Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK
| |
Collapse
|
79
|
Jackson A, Kasah S, Mansour SL, Morrow B, Basson MA. Endoderm-specific deletion of Tbx1 reveals an FGF-independent role for Tbx1 in pharyngeal apparatus morphogenesis. Dev Dyn 2014; 243:1143-51. [PMID: 24812002 DOI: 10.1002/dvdy.24147] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2013] [Revised: 04/01/2014] [Accepted: 04/20/2014] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND The T-box transcription factor Tbx1, is essential for the normal development of multiple organ systems in the embryo. One of the most striking phenotypes in Tbx1-/- embryos is the failure of the caudal pharyngeal pouches to evaginate from the foregut endoderm. Despite considerable interest in the role of Tbx1 in development, the mechanisms whereby Tbx1 controls caudal pouch formation have remained elusive. In particular, the question as to how Tbx1 expression in the pharyngeal endoderm regulates pharyngeal pouch morphogenesis in the mouse embryo is not known. RESULTS To address this question, we produced mouse embryos in which Tbx1 was specifically deleted from the pharyngeal endoderm and, as expected, embryos failed to form caudal pharyngeal pouches. To determine the molecular mechanism, we examined expression of Fgf3 and Fgf8 ligands and downstream effectors. Although Fgf8 expression is greatly reduced in Tbx1-deficient endoderm, FGF signaling levels are unaffected. Furthermore, pouch morphogenesis is only partially perturbed by the loss of both Fgf3 and Fgf8 from the endoderm, indicating that neither are required for pouch formation. CONCLUSIONS Tbx1 deletion from the pharyngeal endoderm is sufficient to cause caudal pharyngeal arch segmentation defects by FGF-independent effectors that remain to be identified.
Collapse
Affiliation(s)
- Abigail Jackson
- Department of Craniofacial Development and Stem Cell Biology, King's College, London, United Kingdom
| | | | | | | | | |
Collapse
|
80
|
Jandzik D, Hawkins MB, Cattell MV, Cerny R, Square TA, Medeiros DM. Roles for FGF in lamprey pharyngeal pouch formation and skeletogenesis highlight ancestral functions in the vertebrate head. Development 2014; 141:629-38. [PMID: 24449839 DOI: 10.1242/dev.097261] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A defining feature of vertebrates (craniates) is a pronounced head supported and protected by a cellularized endoskeleton. In jawed vertebrates (gnathostomes), the head skeleton is made of rigid three-dimensional elements connected by joints. By contrast, the head skeleton of modern jawless vertebrates (agnathans) consists of thin rods of flexible cellular cartilage, a condition thought to reflect the ancestral vertebrate state. To better understand the origin and evolution of the gnathostome head skeleton, we have been analyzing head skeleton development in the agnathan, lamprey. The fibroblast growth factors FGF3 and FGF8 have various roles during head development in jawed vertebrates, including pharyngeal pouch morphogenesis, patterning of the oral skeleton and chondrogenesis. We isolated lamprey homologs of FGF3, FGF8 and FGF receptors and asked whether these functions are ancestral features of vertebrate development or gnathostome novelties. Using gene expression and pharmacological agents, we found that proper formation of the lamprey head skeleton requires two phases of FGF signaling: an early phase during which FGFs drive pharyngeal pouch formation, and a later phase when they directly regulate skeletal differentiation and patterning. In the context of gene expression and functional studies in gnathostomes, our results suggest that these roles for FGFs arose in the first vertebrates and that the evolution of the jaw and gnathostome cellular cartilage was driven by changes developmentally downstream from pharyngeal FGF signaling.
Collapse
Affiliation(s)
- David Jandzik
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Boulder, CO 80309, USA
| | | | | | | | | | | |
Collapse
|
81
|
Edlund RK, Ohyama T, Kantarci H, Riley BB, Groves AK. Foxi transcription factors promote pharyngeal arch development by regulating formation of FGF signaling centers. Dev Biol 2014; 390:1-13. [PMID: 24650709 DOI: 10.1016/j.ydbio.2014.03.004] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Accepted: 03/10/2014] [Indexed: 01/12/2023]
Abstract
The bones of the vertebrate face develop from transient embryonic branchial arches that are populated by cranial neural crest cells. We have characterized a mouse mutant for the Forkhead family transcription factor Foxi3, which is expressed in branchial ectoderm and endoderm. Foxi3 mutant mice are not viable and display severe branchial arch-derived facial skeleton defects, including absence of all but the most distal tip of the mandible and complete absence of the inner, middle and external ear structures. Although cranial neural crest cells of Foxi3 mutants are able to migrate, populate the branchial arches, and display some elements of correct proximo-distal patterning, they succumb to apoptosis from embryonic day 9.75 onwards. We show this cell death correlates with a delay in expression of Fgf8 in branchial arch ectoderm and a failure of neural crest cells in the arches to express FGF-responsive genes. Zebrafish foxi1 is also expressed in branchial arch ectoderm and endoderm, and morpholino knock-down of foxi1 also causes apoptosis of neural crest in the branchial arches. We show that heat shock induction of fgf3 in zebrafish arch tissue can rescue cell death in foxi1 morphants. Our results suggest that Foxi3 may play a role in the establishment of signaling centers in the branchial arches that are required for neural crest survival, patterning and the subsequent development of branchial arch derivatives.
Collapse
Affiliation(s)
- Renée K Edlund
- Program in Developmental Biology, Baylor College of Medicine, BCM295, 1 Baylor Plaza, Houston TX 77030
| | - Takahiro Ohyama
- Division of Cell Biology and Genetics, House Research Institute, 2100 W 3rd St., Los Angeles, CA 90057
| | - Husniye Kantarci
- Biology Department, Texas A&M University, College Station, TX 77843-3258
| | - Bruce B Riley
- Biology Department, Texas A&M University, College Station, TX 77843-3258
| | - Andrew K Groves
- Program in Developmental Biology, Baylor College of Medicine, BCM295, 1 Baylor Plaza, Houston TX 77030.,Department of Molecular and Human Genetics, Baylor College of Medicine, BCM295, 1 Baylor Plaza, Houston TX 77030.,Department of Neuroscience, Baylor College of Medicine, BCM295, 1 Baylor Plaza, Houston TX 77030
| |
Collapse
|
82
|
Whitesell TR, Kennedy RM, Carter AD, Rollins EL, Georgijevic S, Santoro MM, Childs SJ. An α-smooth muscle actin (acta2/αsma) zebrafish transgenic line marking vascular mural cells and visceral smooth muscle cells. PLoS One 2014; 9:e90590. [PMID: 24594685 PMCID: PMC3940907 DOI: 10.1371/journal.pone.0090590] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 02/02/2014] [Indexed: 11/18/2022] Open
Abstract
Mural cells of the vascular system include vascular smooth muscle cells (SMCs) and pericytes whose role is to stabilize and/or provide contractility to blood vessels. One of the earliest markers of mural cell development in vertebrates is α smooth muscle actin (acta2; αsma), which is expressed by pericytes and SMCs. In vivo models of vascular mural cell development in zebrafish are currently lacking, therefore we developed two transgenic zebrafish lines driving expression of GFP or mCherry in acta2-expressing cells. These transgenic fish were used to trace the live development of mural cells in embryonic and larval transgenic zebrafish. acta2:EGFP transgenic animals show expression that largely mirrors native acta2 expression, with early pan-muscle expression starting at 24 hpf in the heart muscle, followed by skeletal and visceral muscle. At 3.5 dpf, expression in the bulbus arteriosus and ventral aorta marks the first expression in vascular smooth muscle. Over the next 10 days of development, the number of acta2:EGFP positive cells and the number of types of blood vessels associated with mural cells increases. Interestingly, the mural cells are not motile and remain in the same position once they express the acta2:EGFP transgene. Taken together, our data suggests that zebrafish mural cells develop relatively late, and have little mobility once they associate with vessels.
Collapse
Affiliation(s)
- Thomas R. Whitesell
- Department of Biochemistry and Molecular Biology, and Smooth Muscle Research Group, University of Calgary, Calgary, Alberta, Canada
| | - Regan M. Kennedy
- Department of Biochemistry and Molecular Biology, and Smooth Muscle Research Group, University of Calgary, Calgary, Alberta, Canada
| | - Alyson D. Carter
- Department of Biochemistry and Molecular Biology, and Smooth Muscle Research Group, University of Calgary, Calgary, Alberta, Canada
| | - Evvi-Lynn Rollins
- Department of Biochemistry and Molecular Biology, and Smooth Muscle Research Group, University of Calgary, Calgary, Alberta, Canada
| | - Sonja Georgijevic
- Department of Biochemistry and Molecular Biology, and Smooth Muscle Research Group, University of Calgary, Calgary, Alberta, Canada
| | - Massimo M. Santoro
- VIB Vesalius Research Center, University of Leuven (KU Leuven), Leuven, Belgium
| | - Sarah J. Childs
- Department of Biochemistry and Molecular Biology, and Smooth Muscle Research Group, University of Calgary, Calgary, Alberta, Canada
| |
Collapse
|
83
|
McGurk PD, Lovely CB, Eberhart JK. Analyzing craniofacial morphogenesis in zebrafish using 4D confocal microscopy. J Vis Exp 2014:e51190. [PMID: 24514435 DOI: 10.3791/51190] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Time-lapse imaging is a technique that allows for the direct observation of the process of morphogenesis, or the generation of shape. Due to their optical clarity and amenability to genetic manipulation, the zebrafish embryo has become a popular model organism with which to perform time-lapse analysis of morphogenesis in living embryos. Confocal imaging of a live zebrafish embryo requires that a tissue of interest is persistently labeled with a fluorescent marker, such as a transgene or injected dye. The process demands that the embryo is anesthetized and held in place in such a way that healthy development proceeds normally. Parameters for imaging must be set to account for three-dimensional growth and to balance the demands of resolving individual cells while getting quick snapshots of development. Our results demonstrate the ability to perform long-term in vivo imaging of fluorescence-labeled zebrafish embryos and to detect varied tissue behaviors in the cranial neural crest that cause craniofacial abnormalities. Developmental delays caused by anesthesia and mounting are minimal, and embryos are unharmed by the process. Time-lapse imaged embryos can be returned to liquid medium and subsequently imaged or fixed at later points in development. With an increasing abundance of transgenic zebrafish lines and well-characterized fate mapping and transplantation techniques, imaging any desired tissue is possible. As such, time-lapse in vivo imaging combines powerfully with zebrafish genetic methods, including analyses of mutant and microinjected embryos.
Collapse
Affiliation(s)
- Patrick D McGurk
- Institute for Cell and Molecular Biology, The University of Texas at Austin
| | | | | |
Collapse
|
84
|
McCarroll MN, Nechiporuk AV. Fgf3 and Fgf10a work in concert to promote maturation of the epibranchial placodes in zebrafish. PLoS One 2013; 8:e85087. [PMID: 24358375 PMCID: PMC3866233 DOI: 10.1371/journal.pone.0085087] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 11/22/2013] [Indexed: 01/02/2023] Open
Abstract
Essential cellular components of the paired sensory organs of the vertebrate head are derived from transient thickenings of embryonic ectoderm known as cranial placodes. The epibranchial (EB) placodes give rise to sensory neurons of the EB ganglia that are responsible for relaying visceral sensations form the periphery to the central nervous system. Development of EB placodes and subsequent formation of EB ganglia is a multistep process regulated by various extrinsic factors, including fibroblast growth factors (Fgfs). We discovered that two Fgf ligands, Fgf3 and Fgf10a, cooperate to promote EB placode development. Whereas EB placodes are induced in the absence of Fgf3 and Fgf10a, they fail to express placode specific markers Pax2a and Sox3. Expression analysis and mosaic rescue experiments demonstrate that Fgf3 signal is derived from the endoderm, whereas Fgf10a is emitted from the lateral line system and the otic placode. Further analyses revealed that Fgf3 and Fgf10a activities are not required for cell proliferation or survival, but are required for placodal cells to undergo neurogenesis. Based on these data, we conclude that a combined loss of these Fgf factors results in a failure of the EB placode precursors to initiate a transcriptional program needed for maturation and subsequent neurogenesis. These findings highlight the importance and complexity of reiterated Fgf signaling during cranial placode formation and subsequent sensory organ development.
Collapse
Affiliation(s)
- Matthew N. McCarroll
- Department of Cell and Developmental Biology, Oregon Health and Science University, Portland, Oregon, United States of America
| | - Alex V. Nechiporuk
- Department of Cell and Developmental Biology, Oregon Health and Science University, Portland, Oregon, United States of America
- * E-mail:
| |
Collapse
|
85
|
Larbuisson A, Dalcq J, Martial JA, Muller M. Fgf receptors Fgfr1a and Fgfr2 control the function of pharyngeal endoderm in late cranial cartilage development. Differentiation 2013; 86:192-206. [DOI: 10.1016/j.diff.2013.07.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 07/01/2013] [Accepted: 07/22/2013] [Indexed: 01/28/2023]
|
86
|
McCarthy N, Wetherill L, Lovely CB, Swartz ME, Foroud TM, Eberhart JK. Pdgfra protects against ethanol-induced craniofacial defects in a zebrafish model of FASD. Development 2013; 140:3254-65. [PMID: 23861062 PMCID: PMC3931738 DOI: 10.1242/dev.094938] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Human birth defects are highly variable and this phenotypic variability can be influenced by both the environment and genetics. However, the synergistic interactions between these two variables are not well understood. Fetal alcohol spectrum disorders (FASD) is the umbrella term used to describe the wide range of deleterious outcomes following prenatal alcohol exposure. Although FASD are caused by prenatal ethanol exposure, FASD are thought to be genetically modulated, although the genes regulating sensitivity to ethanol teratogenesis are largely unknown. To identify potential ethanol-sensitive genes, we tested five known craniofacial mutants for ethanol sensitivity: cyp26b1, gata3, pdgfra, smad5 and smoothened. We found that only platelet-derived growth factor receptor alpha (pdgfra) interacted with ethanol during zebrafish craniofacial development. Analysis of the PDGF family in a human FASD genome-wide dataset links PDGFRA to craniofacial phenotypes in FASD, prompting a mechanistic understanding of this interaction. In zebrafish, untreated pdgfra mutants have cleft palate due to defective neural crest cell migration, whereas pdgfra heterozygotes develop normally. Ethanol-exposed pdgfra mutants have profound craniofacial defects that include the loss of the palatal skeleton and hypoplasia of the pharyngeal skeleton. Furthermore, ethanol treatment revealed latent haploinsufficiency, causing palatal defects in ∼62% of pdgfra heterozygotes. Neural crest apoptosis partially underlies these ethanol-induced defects in pdgfra mutants, demonstrating a protective role for Pdgfra. This protective role is mediated by the PI3K/mTOR pathway. Collectively, our results suggest a model where combined genetic and environmental inhibition of PI3K/mTOR signaling leads to variability within FASD.
Collapse
Affiliation(s)
- Neil McCarthy
- Department of Molecular and Cell and Developmental Biology, Institute for Cellular and Molecular Biology and Institute for Neuroscience, University of Texas, Austin, TX 78712, USA
| | | | | | | | | | | |
Collapse
|
87
|
Lin CY, Lee HC, Chen HC, Hsieh CC, Tsai HJ. Normal function of Myf5 during gastrulation is required for pharyngeal arch cartilage development in zebrafish embryos. Zebrafish 2013; 10:486-99. [PMID: 23992145 DOI: 10.1089/zeb.2013.0903] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Myf5, a myogenic regulatory factor, plays a key role in regulating muscle differentiation. However, it is not known if Myf5 has a regulatory role during early embryogenesis. Here, we used myf5-morpholino oligonucleotides [MO] to knock down myf5 expression and demonstrated a series of results pointing to the functional roles of Myf5 during early embryogenesis: (1) reduced head size resulting from abnormal morphology in the cranial skeleton; (2) decreased expressions of the cranial neural crest (CNC) markers foxd3, sox9a, dlx2, and col2a1; (3) defect in the chondrogenic neural crest similar to that of fgf3 morphants; (4) reduced fgf3/fgf8 transcripts in the cephalic mesoderm rescued by co-injection of myf5 wobble-mismatched mRNA together with myf5-MO1 during 12 h postfertilization; (5) abnormal patterns of axial and non-axial mesoderm causing expansion of the dorsal organizer, and (6) increased bmp4 gradient, but reduced fgf3/fgf8 marginal gradient, during gastrulation. Interestingly, overexpression of fgf3 could rescue the cranial cartilage defects caused by myf5-MO1, suggesting that Myf5 modulates craniofacial cartilage development through the fgf3 signaling pathway. Together, the loss of Myf5 function results in a cascade effect that begins with abnormal formation of the dorsal organizer during gastrulation, causing, in turn, defects in the CNC and cranial cartilage of myf5-knockdown embryos.
Collapse
Affiliation(s)
- Cheng-Yung Lin
- Institute of Molecular and Cellular Biology, National Taiwan University , Taipei, Taiwan
| | | | | | | | | |
Collapse
|
88
|
Choe CP, Collazo A, Trinh LA, Pan L, Moens CB, Crump JG. Wnt-dependent epithelial transitions drive pharyngeal pouch formation. Dev Cell 2013; 24:296-309. [PMID: 23375584 DOI: 10.1016/j.devcel.2012.12.003] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 10/18/2012] [Accepted: 12/03/2012] [Indexed: 01/15/2023]
Abstract
The pharyngeal pouches, which form by budding of the foregut endoderm, are essential for segmentation of the vertebrate face. To date, the cellular mechanism and segmental nature of such budding have remained elusive. Here, we find that Wnt11r and Wnt4a from the head mesoderm and ectoderm, respectively, play distinct roles in the segmental formation of pouches in zebrafish. Time-lapse microscopy, combined with mutant and tissue-specific transgenic experiments, reveal requirements of Wnt signaling in two phases of endodermal epithelial transitions. Initially, Wnt11r and Rac1 destabilize the endodermal epithelium to promote the lateral movement of pouch-forming cells. Next, Wnt4a and Cdc42 signaling induce the rearrangement of maturing pouch cells into bilayers through junctional localization of the Alcama immunoglobulin-domain protein, which functions to restabilize adherens junctions. We propose that this dynamic control of epithelial morphology by Wnt signaling may be a common theme for the budding of organ anlagen from the endoderm.
Collapse
Affiliation(s)
- Chong Pyo Choe
- Broad California Institute of Regenerative Medicine Center, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | | | | | | | | | | |
Collapse
|
89
|
Martínez-Abadías N, Motch SM, Pankratz TL, Wang Y, Aldridge K, Jabs EW, Richtsmeier JT. Tissue-specific responses to aberrant FGF signaling in complex head phenotypes. Dev Dyn 2013; 242:80-94. [PMID: 23172727 PMCID: PMC3556393 DOI: 10.1002/dvdy.23903] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 10/30/2012] [Accepted: 11/02/2012] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND The role of fibroblast growth factor and receptor (FGF/FGFR) signaling in bone development is well studied, partly because mutations in FGFRs cause human diseases of achondroplasia and FGFR-related craniosynostosis syndromes including Crouzon syndrome. The FGFR2c C342Y mutation is a frequent cause of Crouzon syndrome, characterized by premature cranial vault suture closure, midfacial deficiency, and neurocranial dysmorphology. Here, using newborn Fgfr2c(C342Y/+) Crouzon syndrome mice, we tested whether the phenotypic effects of this mutation go beyond the skeletal tissues of the skull, altering the development of other non-skeletal head tissues including the brain, the eyes, the nasopharynx, and the inner ears. RESULTS Quantitative analysis of 3D multimodal imaging (high-resolution micro-computed tomography and magnetic resonance microscopy) revealed local differences in skull morphology and coronal suture patency between Fgfr2c(C342Y/+) mice and unaffected littermates, as well as changes in brain shape but not brain size, significant reductions in nasopharyngeal and eye volumes, and no difference in inner ear volume in Fgfr2c(C342Y/+) mice. CONCLUSIONS These findings provide an expanded catalogue of clinical phenotypes in Crouzon syndrome caused by aberrant FGF/FGFR signaling and evidence of the broad role for FGF/FGFR signaling in development and evolution of the vertebrate head.
Collapse
Affiliation(s)
- Neus Martínez-Abadías
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania
| | - Susan M. Motch
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania
| | - Talia L. Pankratz
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania
| | - Yingli Wang
- Department of Genetics and Genomic Sciences, Mount Sinai SOM, New York, New York
| | - Kristina Aldridge
- Department of Pathology and Anatomical Sciences, University of Missouri SOM, Columbia, MO
| | - Ethylin Wang Jabs
- Department of Genetics and Genomic Sciences, Mount Sinai SOM, New York, New York
| | - Joan T. Richtsmeier
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania
| |
Collapse
|
90
|
Abstract
Taste buds are found in a distributed array on the tongue surface, and are innervated by cranial nerves that convey taste information to the brain. For nearly a century, taste buds were thought to be induced by nerves late in embryonic development. However, this view has shifted dramatically. A host of studies now indicate that taste bud development is initiated and proceeds via processes that are nerve-independent, occur long before birth, and governed by cellular and molecular mechanisms intrinsic to the developing tongue. Here we review the state of our understanding of the molecular and cellular regulation of taste bud development, incorporating important new data obtained through the use of two powerful genetic systems, mouse and zebrafish.
Collapse
|
91
|
Jayasena CS, Bronner ME. Rbms3 functions in craniofacial development by posttranscriptionally modulating TGF-β signaling. ACTA ACUST UNITED AC 2012; 199:453-66. [PMID: 23091072 PMCID: PMC3483135 DOI: 10.1083/jcb.201204138] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Rbms3 regulates TGF-βr signaling, a critical pathway for chondrogenesis, by binding and stabilizing Smad2 transcripts. Cranial neural crest cells form much of the facial skeleton, and abnormalities in their development lead to severe birth defects. In a novel zebrafish protein trap screen, we identified an RNA-binding protein, Rbms3, that is transiently expressed in the cytoplasm of condensing neural crest cells within the pharyngeal arches. Morphants for rbms3 displayed reduced proliferation of prechondrogenic crest and significantly altered expression for chondrogenic/osteogenic lineage markers. This phenotype strongly resembles cartilage/crest defects observed in Tgf-βr2:Wnt1-Cre mutants, which suggests a possible link with TGF-β signaling. Consistent with this are the findings that: (a) Rbms3 stabilized a reporter transcript with smad2 3′ untranslated region, (b) RNA immunoprecipitation with full-length Rbms3 showed enrichment for smad2/3, and (c) pSmad2 levels were reduced in rbms3 morphants. Overall, these results suggest that Rbms3 posttranscriptionally regulates one of the major pathways that promotes chondrogenesis, the transforming growth factor β receptor (TGF-βr) pathway.
Collapse
|
92
|
Talbot JC, Walker MB, Carney TJ, Huycke TR, Yan YL, BreMiller RA, Gai L, Delaurier A, Postlethwait JH, Hammerschmidt M, Kimmel CB. fras1 shapes endodermal pouch 1 and stabilizes zebrafish pharyngeal skeletal development. Development 2012; 139:2804-13. [PMID: 22782724 DOI: 10.1242/dev.074906] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Lesions in the epithelially expressed human gene FRAS1 cause Fraser syndrome, a complex disease with variable symptoms, including facial deformities and conductive hearing loss. The developmental basis of facial defects in Fraser syndrome has not been elucidated. Here we show that zebrafish fras1 mutants exhibit defects in facial epithelia and facial skeleton. Specifically, fras1 mutants fail to generate a late-forming portion of pharyngeal pouch 1 (termed late-p1) and skeletal elements adjacent to late-p1 are disrupted. Transplantation studies indicate that fras1 acts in endoderm to ensure normal morphology of both skeleton and endoderm, consistent with well-established epithelial expression of fras1. Late-p1 formation is concurrent with facial skeletal morphogenesis, and some skeletal defects in fras1 mutants arise during late-p1 morphogenesis, indicating a temporal connection between late-p1 and skeletal morphogenesis. Furthermore, fras1 mutants often show prominent second arch skeletal fusions through space occupied by late-p1 in wild type. Whereas every fras1 mutant shows defects in late-p1 formation, skeletal defects are less penetrant and often vary in severity, even between the left and right sides of the same individual. We interpret the fluctuating asymmetry in fras1 mutant skeleton and the changes in fras1 mutant skeletal defects through time as indicators that skeletal formation is destabilized. We propose a model wherein fras1 prompts late-p1 formation and thereby stabilizes skeletal formation during zebrafish facial development. Similar mechanisms of stochastic developmental instability might also account for the high phenotypic variation observed in human FRAS1 patients.
Collapse
|
93
|
Seritrakul P, Samarut E, Lama TTS, Gibert Y, Laudet V, Jackman WR. Retinoic acid expands the evolutionarily reduced dentition of zebrafish. FASEB J 2012; 26:5014-24. [PMID: 22942074 DOI: 10.1096/fj.12-209304] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Zebrafish lost anterior teeth during evolution but retain a posterior pharyngeal dentition that requires retinoic acid (RA) cell-cell signaling for its development. The purposes of this study were to test the sufficiency of RA to induce tooth development and to assess its role in evolution. We found that exposure of embryos to exogenous RA induces a dramatic anterior expansion of the number of pharyngeal teeth that later form and shifts anteriorly the expression patterns of genes normally expressed in the posterior tooth-forming region, such as pitx2 and dlx2b. After RA exposure, we also observed a correlation between cartilage malformations and ectopic tooth induction, as well as abnormal cranial neural crest marker gene expression. Additionally, we observed that the RA-induced zebrafish anterior teeth resemble in pattern and number the dentition of fish species that retain anterior pharyngeal teeth such as medaka but that medaka do not express the aldh1a2 RA-synthesizing enzyme in tooth-forming regions. We conclude that RA is sufficient to induce anterior ectopic tooth development in zebrafish where teeth were lost in evolution, potentially by altering neural crest cell development, and that changes in the location of RA synthesis correlate with evolutionary changes in vertebrate dentitions.
Collapse
Affiliation(s)
- Pawat Seritrakul
- Department of Biology, Bowdoin College, 6500 College Station, Brunswick, ME 04011, USA
| | | | | | | | | | | |
Collapse
|
94
|
Swartz ME, Nguyen V, McCarthy NQ, Eberhart JK. Hh signaling regulates patterning and morphogenesis of the pharyngeal arch-derived skeleton. Dev Biol 2012; 369:65-75. [PMID: 22709972 DOI: 10.1016/j.ydbio.2012.05.032] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 05/24/2012] [Accepted: 05/26/2012] [Indexed: 01/17/2023]
Abstract
The proper function of the craniofacial skeleton requires the proper shaping of many individual skeletal elements. Neural crest cells generate much of the craniofacial skeleton and morphogenesis of skeletal elements occurs in transient, reiterated structures termed pharyngeal arches. The shape of individual elements depends upon intrinsic patterning within the neural crest as well as extrinsic signals to the neural crest from adjacent tissues within the arches. Hedgehog (Hh) signaling is known to play roles in craniofacial development, yet its involvement in intrinsic and extrinsic patterning of the craniofacial skeleton is still not well understood. Here, we show that morphogenetic movements of the pharyngeal arches and patterning of the neural crest require Hh signaling. Loss of Hh signaling, in smoothened (smo) mutants, disrupts the expression of some Dlx genes as well as other markers of dorsal/ventral patterning of the neural crest. Transplantation of wild-type neural crest cells into smo mutants rescues this defect, demonstrating that the neural crest requires reception of Hh signals for proper patterning. Despite the rescue, morphogenesis of the facial skeleton is not fully recovered. Through transplant analyses, we find two additional requirements for Hh signaling. The endoderm requires the reception of Hh signals for proper morphogenetic movements of the pharyngeal arches and the neural crest require the reception of Hh signaling for the activity of a reverse signal that maintains sonic hedgehog expression in the endoderm. Collectively, these results demonstrate that Hh signaling is essential to establish intrinsic and extrinsic patterning information for the craniofacial skeleton.
Collapse
Affiliation(s)
- Mary E Swartz
- Section of Molecular, Cell and Developmental Biology, Institute of Cellular and Molecular Biology, University of Texas at Austin, USA
| | | | | | | |
Collapse
|
95
|
Swartz ME, Sheehan-Rooney K, Dixon MJ, Eberhart JK. Examination of a palatogenic gene program in zebrafish. Dev Dyn 2012; 240:2204-20. [PMID: 22016187 DOI: 10.1002/dvdy.22713] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Human palatal clefting is debilitating and difficult to rectify surgically. Animal models enhance our understanding of palatogenesis and are essential in strategies designed to ameliorate palatal malformations in humans. Recent studies have shown that the zebrafish palate, or anterior neurocranium, is under similar genetic control to the amniote palatal skeleton. We extensively analyzed palatogenesis in zebrafish to determine the similarity of gene expression and function across vertebrates. By 36 hours postfertilization (hpf) palatogenic cranial neural crest cells reside in homologous regions of the developing face compared with amniote species. Transcription factors and signaling molecules regulating mouse palatogenesis are expressed in similar domains during palatogenesis in zebrafish. Functional investigation of a subset of these genes, fgf10a, tgfb2, pax9, and smad5 revealed their necessity in zebrafish palatogenesis. Collectively, these results suggest that the gene regulatory networks regulating palatogenesis may be conserved across vertebrate species, demonstrating the utility of zebrafish as a model for palatogenesis.
Collapse
Affiliation(s)
- Mary E Swartz
- Department of Molecular and Cell and Developmental Biology, Institute for Cellular and Molecular Biology and Institute for Neuroscience, University of Texas, Austin, Texas, USA.
| | | | | | | |
Collapse
|
96
|
Das A, Crump JG. Bmps and id2a act upstream of Twist1 to restrict ectomesenchyme potential of the cranial neural crest. PLoS Genet 2012; 8:e1002710. [PMID: 22589745 PMCID: PMC3349740 DOI: 10.1371/journal.pgen.1002710] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Accepted: 03/28/2012] [Indexed: 11/18/2022] Open
Abstract
Cranial neural crest cells (CNCCs) have the remarkable capacity to generate both the non-ectomesenchyme derivatives of the peripheral nervous system and the ectomesenchyme precursors of the vertebrate head skeleton, yet how these divergent lineages are specified is not well understood. Whereas studies in mouse have indicated that the Twist1 transcription factor is important for ectomesenchyme development, its role and regulation during CNCC lineage decisions have remained unclear. Here we show that two Twist1 genes play an essential role in promoting ectomesenchyme at the expense of non-ectomesenchyme gene expression in zebrafish. Twist1 does so by promoting Fgf signaling, as well as potentially directly activating fli1a expression through a conserved ectomesenchyme-specific enhancer. We also show that Id2a restricts Twist1 activity to the ectomesenchyme lineage, with Bmp activity preferentially inducing id2a expression in non-ectomesenchyme precursors. We therefore propose that the ventral migration of CNCCs away from a source of Bmps in the dorsal ectoderm promotes ectomesenchyme development by relieving Id2a-dependent repression of Twist1 function. Together our model shows how the integration of Bmp inhibition at its origin and Fgf activation along its migratory route would confer temporal and spatial specificity to the generation of ectomesenchyme from the neural crest.
Collapse
Affiliation(s)
| | - J. Gage Crump
- Broad CIRM Center, University of Southern California Keck School of Medicine, Los Angeles, California, United States of America
- * E-mail:
| |
Collapse
|
97
|
Anastasaki C, Rauen KA, Patton EE. Continual low-level MEK inhibition ameliorates cardio-facio-cutaneous phenotypes in zebrafish. Dis Model Mech 2012; 5:546-52. [PMID: 22301711 PMCID: PMC3380717 DOI: 10.1242/dmm.008672] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Cardio-facio-cutaneous (CFC) syndrome is caused by germline mutations in KRAS, BRAF and MEK1/2. The highly selective and potent MEK inhibitors that have been developed as anti-cancer agents hold potential as therapeutics for CFC syndrome. We have previously shown that the effects of CFC mutations on zebrafish gastrulation can be prevented by a 1-hour treatment with MEK inhibitors within a specific developmental time-window. However, MEK activity is essential for normal development and PD0325901 treatment outside this treatment window leads to additional developmental defects in MEK-dependent tissues. We now test ten different doses of PD0325901 at six developmental time points and assess the effects on body axis length, heart development and craniofacial structures in zebrafish embryos. Notably, we find that a continuous low-level dose of PD0325901 that has only minor inhibition of MEK activity can prevent the action of both the common CFC BRAFQ257R kinase-active allele and the BRAFG596V kinase-impaired mutant allele through the first 5 days of development. These results provide a detailed study of the effects of PD0325901 in development and show that, unlike in cancer, which requires robust inhibition of MAPK signalling, a partial reduction in phospho-ERK1/2 activity is sufficient to moderate the developmental effects of BRAFCFC mutations.
Collapse
Affiliation(s)
- Corina Anastasaki
- The Institute for Genetics and Molecular Medicine, Medical Research Council, Human Genetics Unit and Edinburgh University, Crewe Road South, Western General Hospital Campus, EH4 2XR, UK
| | | | | |
Collapse
|
98
|
Chen Y, Moon AM, Gaufo GO. Influence of mesodermal Fgf8 on the differentiation of neural crest-derived postganglionic neurons. Dev Biol 2011; 361:125-36. [PMID: 22040872 DOI: 10.1016/j.ydbio.2011.10.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 09/21/2011] [Accepted: 10/16/2011] [Indexed: 01/06/2023]
Abstract
The interaction between the cranial neural crest (NC) and the epibranchial placode is critical for the formation of parasympathetic and visceral sensory ganglia, respectively. However, the molecular mechanism that controls this intercellular interaction is unknown. Here we show that the spatiotemporal expression of Fibroblast growth factor 8 (Fgf8) is strategically poised to control this cellular relationship. A global reduction of Fgf8 in hypomorph embryos leads to an early loss of placode-derived sensory ganglia and reduced number of NC-derived postganglionic (PG) neurons. The latter finding is associated with the early loss of NC cells by apoptosis. This loss occurs concurrent with the interaction between the NC and placode-derived ganglia. Conditional knockout of Fgf8 in the anterior mesoderm shows that this tissue source of Fgf8 has a specific influence on the formation of PG neurons. Unlike the global reduction of Fgf8, mesodermal loss of Fgf8 leads to a deficiency in PG neurons that is independent of NC apoptosis or defects in placode-derived ganglia. We further examined the differentiation of PG precursors by using a quantitative approach to measure the intensity of Phox2b, a PG neuronal determinant. We found reduced numbers and immature state of PG precursors emerging from the placode-derived ganglia en route to their terminal target areas. Our findings support the view that global expression of Fgf8 is required for early NC survival and differentiation of placode-derived sensory neurons, and reveal a novel role for mesodermal Fgf8 on the early differentiation of the NC along the parasympathetic PG lineage.
Collapse
Affiliation(s)
- Yiju Chen
- Department of Biology, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, USA
| | | | | |
Collapse
|
99
|
Kapsimali M, Kaushik AL, Gibon G, Dirian L, Ernest S, Rosa FM. Fgf signaling controls pharyngeal taste bud formation through miR-200 and Delta-Notch activity. Development 2011; 138:3473-84. [PMID: 21791527 DOI: 10.1242/dev.058669] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Taste buds, the taste sensory organs, are conserved in vertebrates and composed of distinct cell types, including taste receptor, basal/presynaptic and support cells. Here, we characterize zebrafish taste bud development and show that compromised Fgf signaling in the larva results in taste bud reduction and disorganization. We determine that Fgf activity is required within pharyngeal endoderm for formation of Calb2b(+) cells and reveal miR-200 and Delta-Notch signaling as key factors in this process. miR-200 knock down shows that miR-200 activity is required for taste bud formation and in particular for Calb2b(+) cell formation. Compromised delta activity in mib(-/-) dramatically reduces the number of Calb2b(+) cells and increases the number of 5HT(+) cells. Conversely, larvae with increased Notch activity and ascl1a(-/-) mutants are devoid of 5HT(+) cells, but have maintained and increased Calb2b(+) cells, respectively. These results show that Delta-Notch signaling is required for intact taste bud organ formation. Consistent with this, Notch activity restores Calb2b(+) cell formation in pharyngeal endoderm with compromised Fgf signaling, but fails to restore the formation of these cells after miR-200 knock down. Altogether, this study provides genetic evidence that supports a novel model where Fgf regulates Delta-Notch signaling, and subsequently miR-200 activity, in order to promote taste bud cell type differentiation.
Collapse
Affiliation(s)
- Marika Kapsimali
- Ecole Normale Supérieure, Institut de Biologie, 75005 Paris, France.
| | | | | | | | | | | |
Collapse
|
100
|
Simões FC, Peterkin T, Patient R. Fgf differentially controls cross-antagonism between cardiac and haemangioblast regulators. Development 2011; 138:3235-45. [PMID: 21750034 DOI: 10.1242/dev.059634] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Fibroblast growth factor (Fgf) has been implicated in the control of heart size during development, although whether this is by controlling cell fate, survival or proliferation has not been clear. Here, we show that Fgf, without affecting survival or proliferation, acts during gastrulation to drive cardiac fate and restrict anterior haemangioblast fate in zebrafish embryos. The haemangioblast programme was thought to be activated before the cardiac programme and is repressive towards it, suggesting that activation by Fgf of the cardiac programme might be via suppression of the haemangioblast programme. However, we show that the cardiac regulator nkx2.5 can also repress the haemangioblast programme and, furthermore, that cardiac specification still requires Fgf signalling even when haemangioblast regulators are independently suppressed. We further show that nkx2.5 and the cloche candidate gene lycat are expressed during gastrulation and regulated by Fgf, and that nkx2.5 overexpression, together with loss of the lycat targets etsrp and scl can stably induce expansion of the heart. We conclude that Fgf controls cardiac and haemangioblast fates by the simultaneous regulation of haemangioblast and cardiac regulators. We propose that elevation of Fgf signalling in the anterior haemangioblast territory could have led to its recruitment into the heart field during evolution, increasing the size of the heart.
Collapse
Affiliation(s)
- Filipa Costa Simões
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, Oxford University, John Radcliffe Hospital, Headington OX3 9DS, UK
| | | | | |
Collapse
|