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Reynolds S, Pierce C, Powell B, Kite A, Hall-Ruiz N, Schilling T, Le Pabic P. A show of Hands: Novel and conserved expression patterns of teleost hand paralogs during craniofacial, heart, fin, peripheral nervous system and gut development. Dev Dyn 2021; 250:1796-1809. [PMID: 34091971 PMCID: PMC8639631 DOI: 10.1002/dvdy.380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Revised: 05/14/2021] [Accepted: 06/03/2021] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Hand genes are required for the development of the vertebrate jaw, heart, peripheral nervous system, limb, gut, placenta, and decidua. Two Hand paralogues, Hand1 and Hand2, are present in most vertebrates, where they mediate different functions yet overlap in expression. In ray-finned fishes, Hand gene expression and function is only known for the zebrafish, which represents the rare condition of having a single Hand gene, hand2. Here we describe the developmental expression of hand1 and hand2 in the cichlid Copadichromis azureus. RESULTS hand1 and hand2 are expressed in the cichlid heart, paired fins, pharyngeal arches, peripheral nervous system, gut, and lateral plate mesoderm with different degrees of overlap. CONCLUSIONS Hand gene expression in the gut, peripheral nervous system, and pharyngeal arches may have already been fixed in the lobe- and ray-finned fish common ancestor. In other embryonic regions, such as paired appendages, hand2 expression was fixed, while hand1 expression diverged in lobe- and ray-finned fish lineages. In the lateral plate mesoderm and arch associated catecholaminergic cells, hand1 and hand2 swapped expression between divergent lineages. Distinct expression of cichlid hand1 and hand2 in the epicardium and myocardium of the developing heart may represent the ancestral pattern for bony fishes.
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Affiliation(s)
- Samantha Reynolds
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina
| | - Christian Pierce
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina
| | - Benjamin Powell
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina
| | - Alexandra Kite
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina
| | - Nicholas Hall-Ruiz
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina
| | - Thomas Schilling
- Department of Developmental and Cell Biology, University of California Irvine, Irvine, California
| | - Pierre Le Pabic
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina
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Berio F, Debiais-Thibaud M. Evolutionary developmental genetics of teeth and odontodes in jawed vertebrates: a perspective from the study of elasmobranchs. J Fish Biol 2021; 98:906-918. [PMID: 31820456 DOI: 10.1111/jfb.14225] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 12/09/2019] [Indexed: 06/10/2023]
Abstract
Most extant vertebrates display a high variety of tooth and tooth-like organs (odontodes) that vary in shape, position over the body and nature of composing tissues. The development of these structures is known to involve similar genetic cascades and teeth and odontodes are believed to share a common evolutionary history. Gene expression patterns have previously been compared between mammalian and teleost tooth development but we highlight how the comparative framework was not always properly defined to deal with different tooth types or tooth developmental stages. Larger-scale comparative analyses also included cartilaginous fishes: sharks display oral teeth and dermal scales for which the gene expression during development started to be investigated in the small-spotted catshark Scyliorhinus canicula during the past decade. We report several descriptive approaches to analyse the embryonic tooth and caudal scale gene expressions in S. canicula. We compare these expressions wih the ones reported in mouse molars and teleost oral and pharyngeal teeth and highlight contributions and biases that arise from these interspecific comparisons. We finally discuss the evolutionary processes that can explain the observed intra and interspecific similarities and divergences in the genetic cascades involved in tooth and odontode development in jawed vertebrates.
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Affiliation(s)
- Fidji Berio
- Institut des Sciences de l'Evolution de Montpellier, ISEM, Univ Montpellier, CNRS, IRD, EPHE, Montpellier, France
- University of Lyon, Ecole Normale Supérieure de Lyon, Centre National de la Recherche Scientifique, Université Claude Bernard Lyon 1, Institut de Génomique Fonctionnelle de Lyon, UMR5242, 46 Allée d'Italie, Lyon, France
| | - Mélanie Debiais-Thibaud
- Institut des Sciences de l'Evolution de Montpellier, ISEM, Univ Montpellier, CNRS, IRD, EPHE, Montpellier, France
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3
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Neupane S, Aryal YP, Kim TY, Yeon CY, An CH, Kim JY, Yamamoto H, Lee Y, Sohn WJ, Kim JY. Signaling Modulations of miR-206-3p in Tooth Morphogenesis. Int J Mol Sci 2020; 21:E5251. [PMID: 32722078 PMCID: PMC7432545 DOI: 10.3390/ijms21155251] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/22/2020] [Accepted: 07/22/2020] [Indexed: 01/06/2023] Open
Abstract
MicroRNAs (miRNAs) are a class of naturally occurring small non-coding RNAs that post-transcriptionally regulate gene expression in organisms. Most mammalian miRNAs influence biological processes, including developmental changes, tissue morphogenesis and the maintenance of tissue identity, cell growth, differentiation, apoptosis, and metabolism. The miR-206-3p has been correlated with cancer; however, developmental roles of this miRNA are unclear. In this study, we examined the expression pattern and evaluated the developmental regulation of miR-206-3p during tooth morphogenesis using ex-vivo culture method. The expression pattern of miR-206-3p was examined in the epithelium and mesenchyme of developing tooth germ with stage-specific manners. Perturbation of the expression of miR-206-3p clearly altered expression patterns of dental-development-related signaling molecules, including Axin2, Bmp2, Fgf4, Lef1 and Shh. The gene expression complemented with change in cellular events including, apoptosis and proliferation which caused altered crown and pulp morphogenesis in renal-capsule-calcified teeth. Especially, mislocalization of β-Catenin and SMAD1/5/8 were observed alongside dramatic alterations in the expression patterns of Fgf4 and Shh. Overall, our data suggest that the miR-206-3p regulate the cellular physiology during tooth morphogenesis through modulation of the Wnt, Bmp, Fgf, and Shh signaling pathways to form proper tooth pulp and crown.
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Affiliation(s)
- Sanjiv Neupane
- Department of Biochemistry, School of Dentistry, Kyungpook National University, Daegu 41940, Korea; (Y.P.A.); (T.-Y.K.); (C.-Y.Y.); (Y.L.)
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
| | - Yam Prasad Aryal
- Department of Biochemistry, School of Dentistry, Kyungpook National University, Daegu 41940, Korea; (Y.P.A.); (T.-Y.K.); (C.-Y.Y.); (Y.L.)
| | - Tae-Young Kim
- Department of Biochemistry, School of Dentistry, Kyungpook National University, Daegu 41940, Korea; (Y.P.A.); (T.-Y.K.); (C.-Y.Y.); (Y.L.)
| | - Chang-Yeol Yeon
- Department of Biochemistry, School of Dentistry, Kyungpook National University, Daegu 41940, Korea; (Y.P.A.); (T.-Y.K.); (C.-Y.Y.); (Y.L.)
| | - Chang-Hyeon An
- Department of Oral and Maxillofacial Radiology, School of Dentistry, Kyungpook National University, Daegu 41940, Korea;
| | - Ji-Youn Kim
- Department of Dental Hygiene, College of Health Science, Gachon University, Incheon 21936, Korea;
| | - Hitoshi Yamamoto
- Department of Histology and Developmental Biology, Tokyo Dental College, Tokyo 101-0061, Japan;
| | - Youngkyun Lee
- Department of Biochemistry, School of Dentistry, Kyungpook National University, Daegu 41940, Korea; (Y.P.A.); (T.-Y.K.); (C.-Y.Y.); (Y.L.)
| | - Wern-Joo Sohn
- Pre-Major of Cosmetics and Pharmaceutics, Daegu Haany University, Gyeongsan 38610, Korea;
| | - Jae-Young Kim
- Department of Biochemistry, School of Dentistry, Kyungpook National University, Daegu 41940, Korea; (Y.P.A.); (T.-Y.K.); (C.-Y.Y.); (Y.L.)
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Wu J, Li H, Han L, Sun T, Tian Y, Wang X. The spatiotemporal expression pattern of Syndecans in murine embryonic teeth. Gene Expr Patterns 2020; 36:119109. [PMID: 32220631 DOI: 10.1016/j.gep.2020.119109] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 03/13/2020] [Accepted: 03/16/2020] [Indexed: 02/05/2023]
Abstract
The hierarchical interactions between the dental epithelium and dental mesenchyme represent a common paradigm for organogenesis. During tooth development, various morphogens interact with extracellular components in the extracellular matrix and on the cell surfaces to transmit regulatory signaling into cells. We recently found pivotal roles of FAM20B-catalyzed proteoglycans in the control of murine tooth number at embryonic stages. However, the expression pattern of proteoglycans in embryonic teeth has not been well understood. We extracted total RNA from E14.5 murine tooth germs for semi-quantitative RT-PCR analysis of 29 proteoglycans, and identified 23 of them in the embryonic teeth. As a major subfamily of FAM20B-catalyzed proteoglycans, Syndecans are important candidates being potentially involved in the tooth development of mice. We examined the expression pattern of Syndecans in embryonic teeth using in situ hybridization (ISH) and immunohistochemistry (IHC) approaches. Syndecan-1 is mainly present in the dental mesenchyme at early embryonic stages. Subsequently, its expression expands to both dental epithelium and dental mesenchyme. Syndecan-2 is strongly expressed in the dental mesenchyme at early embryonic stages, then shifts to the stratum intermedium and inner dental epithelium at cap stages. Syndecan-3 shows a gradually increased expression that initially in the dental epithelium of both incisors and molars and then in the inner dental epithelium and stratum intermedium in molars alone. Syndecan-4 is localized in the dental epithelium in incisors and the dental follicle mesenchyme in molars at early cap stage. The spatiotemporal expression pattern of Syndecans in murine embryonic teeth suggest potential roles of these proteoglycans in murine tooth morphogenesis.
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Affiliation(s)
- Jingyi Wu
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA, 75246; Stomatological Hospital, Southern Medical University, Guangzhou, Guangdong, 510280, China
| | - Hong Li
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA, 75246; Beijing Stomatological Hospital, Capital Medical University, Beijing, 100050, China
| | - Lu Han
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA, 75246; West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, 610000, China
| | - Tianyu Sun
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA, 75246; Stomatological Hospital, Southern Medical University, Guangzhou, Guangdong, 510280, China
| | - Ye Tian
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA, 75246; West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, 610000, China
| | - Xiaofang Wang
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA, 75246.
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Abstract
Explaining how the extensive diversity in form of vertebrate teeth arose in evolution and the mechanisms by which teeth are made during embryogenesis are intertwined questions that can merit from a better understanding of the roles of retinoic acid (RA) in tooth development. Pioneering studies in rodents showed that dietary vitamin A (VA), and eventually RA (one of the major active metabolites of VA), are required for proper tooth formation and that dentin-forming odontoblast cells seem to be especially sensitive to changes in RA levels. Later, rodent studies further indicated that RA signaling interactions with other cell-signaling pathways are an important part of RA's actions in odontogenesis. Recent investigations employing zebrafish and other teleost fish continued this work in an evolutionary context, and specifically demonstrated that RA is required for the initiation of tooth development. RA is also sufficient in certain circumstances to induce de novo tooth formation. Both effects appear to involve cranial-neural crest cells, again suggesting that RA signaling has a particular influence on odontoblast development. These teleost studies have also highlighted both evolutionary conservation and change in how RA is employed during odontogenesis in different vertebrate lineages, and thus raises the possibility that developmental changes to RA signaling has led to some of the diversity of form seen across vertebrate dentitions. Future progress in this area will come at least in part from expanding the species examined to get a better picture of how often RA signaling has changed in evolution and how this relates to the evolution of dental form.
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Affiliation(s)
| | - Yann Gibert
- University of Mississippi Medical Center, Jackson, MS, 39216, USA
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The people behind the papers - Elena Popa and Abigail Tucker. Development 2019; 146:dev176313. [PMID: 30737241 DOI: 10.1242/dev.176313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
While many vertebrates have multiple sets of teeth over their lifetime, some, like humans, have just a single set of replacement teeth (diphydonty), while others, like mice, manage with a single set (monophydonty). This diversity raises both evolutionary questions - how did different tooth replacement strategies evolve? - and developmental ones - what mechanisms prevent replacement teeth in animals that have lost them? A new paper in this issue of Development tackles these questions with a molecular analysis of mouse tooth development. We caught up with first author Elena Popa and her supervisor Abigail Tucker, Professor of Development and Evolution at King's College London, to find out more about the work.
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Vaida LL, Moca AE, Todor L, Ţenţ A, Todor BI, Negruţiu BM, Moraru AI. Correlations between morphology of cervical vertebrae and dental eruption. Rom J Morphol Embryol 2019; 60:175-180. [PMID: 31263842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The process of dental eruption is submitted to physiological and pathological variables. A series of discrepancies may occur, one of these being a disturbance between dental age and bone age. The assessment of bone age is best made with the cervical vertebral maturation (CVM) method, simplified by Baccetti et al. (2005). The sample studied consisted of 215 orthodontic patients. The dental age was assessed on the orthopantomograph radiographies and the bone age on the lateral cephalograms. For determining the bone age, CVM method was used. Considering dental age, most of the patients (50.2%) have a premature dental age compared to bone age, while patients with normal dental age (27.9%) and patients with late dental age (21.9%) have a lower frequency. The correlation between the dental age and the bone age of the patients shows that patients who have higher values of dental age also have higher values of bone age (p<0.001). The correlation between genders shows that female patients tend to have a higher average value of bone age in comparison to male patients (p<0.001). The authors conclude that assessing bone age based on the morphology of cervical vertebrae and correlating it with the dental age could be of great use in opting for a certain orthodontic treatment plan.
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Affiliation(s)
- Luminiţa Ligia Vaida
- Department of Dental Medicine, Faculty of Medicine and Pharmacy, University of Oradea, Romania; ,
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Calamari ZT, Kuang-Hsien Hu J, Klein OD. Tissue Mechanical Forces and Evolutionary Developmental Changes Act Through Space and Time to Shape Tooth Morphology and Function. Bioessays 2018; 40:e1800140. [PMID: 30387177 PMCID: PMC6516060 DOI: 10.1002/bies.201800140] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 10/06/2018] [Indexed: 12/24/2022]
Abstract
Efforts from diverse disciplines, including evolutionary studies and biomechanical experiments, have yielded new insights into the genetic, signaling, and mechanical control of tooth formation and functions. Evidence from fossils and non-model organisms has revealed that a common set of genes underlie tooth-forming potential of epithelia, and changes in signaling environments subsequently result in specialized dentitions, maintenance of dental stem cells, and other phenotypic adaptations. In addition to chemical signaling, tissue forces generated through epithelial contraction, differential growth, and skeletal constraints act in parallel to shape the tooth throughout development. Here recent advances in understanding dental development from these studies are reviewed and important gaps that can be filled through continued application of evolutionary and biomechanical approaches are discussed.
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Affiliation(s)
- Zachary T. Calamari
- Department of Natural Sciences, Baruch College, City University of New York, New York City, New York, 10010, USA
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco, California, 94143, USA
| | - Jimmy Kuang-Hsien Hu
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco, California, 94143, USA
| | - Ophir D. Klein
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco, California, 94143, USA
- Department of Pediatrics and Institute for Human Genetics, University of California, San Francisco, San Francisco, California, 94143, USA
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9
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Enault S, Muñoz D, Simion P, Ventéo S, Sire JY, Marcellini S, Debiais-Thibaud M. Evolution of dental tissue mineralization: an analysis of the jawed vertebrate SPARC and SPARC-L families. BMC Evol Biol 2018; 18:127. [PMID: 30165817 PMCID: PMC6117938 DOI: 10.1186/s12862-018-1241-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 08/15/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The molecular bases explaining the diversity of dental tissue mineralization across gnathostomes are still poorly understood. Odontodes, such as teeth and body denticles, are serial structures that develop through deployment of a gene regulatory network shared between all gnathostomes. Dentin, the inner odontode mineralized tissue, is produced by odontoblasts and appears well-conserved through evolution. In contrast, the odontode hypermineralized external layer (enamel or enameloid) produced by ameloblasts of epithelial origin, shows extensive structural variations. As EMP (Enamel Matrix Protein) genes are as yet only found in osteichthyans where they play a major role in the mineralization of teeth and others skeletal organs, our understanding of the molecular mechanisms leading to the mineralized odontode matrices in chondrichthyans remains virtually unknown. RESULTS We undertook a phylogenetic analysis of the SPARC/SPARC-L gene family, from which the EMPs are supposed to have arisen, and examined the expression patterns of its members and of major fibrillar collagens in the spotted catshark Scyliorhinus canicula, the thornback ray Raja clavata, and the clawed frog Xenopus tropicalis. Our phylogenetic analyses reveal that the single chondrichthyan SPARC-L gene is co-orthologous to the osteichthyan SPARC-L1 and SPARC-L2 paralogues. In all three species, odontoblasts co-express SPARC and collagens. In contrast, ameloblasts do not strongly express collagen genes but exhibit strikingly similar SPARC-L and EMP expression patterns at their maturation stage, in the examined chondrichthyan and osteichthyan species, respectively. CONCLUSIONS A well-conserved odontoblastic collagen/SPARC module across gnathostomes further confirms dentin homology. Members of the SPARC-L clade evolved faster than their SPARC paralogues, both in terms of protein sequence and gene duplication. We uncover an osteichthyan-specific duplication that produced SPARC-L1 (subsequently lost in pipidae frogs) and SPARC-L2 (independently lost in teleosts and tetrapods).Our results suggest the ameloblastic expression of the single chondrichthyan SPARC-L gene at the maturation stage reflects the ancestral gnathostome situation, and provide new evidence in favor of the homology of enamel and enameloids in all gnathostomes.
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Affiliation(s)
- Sébastien Enault
- Institut des Sciences de l’Evolution de Montpellier, ISEM, Univ Montpellier, CNRS, IRD, EPHE, Université Montpellier, UMR5554 Montpellier, France
| | - David Muñoz
- Laboratory of Development and Evolution, Department of Cell Biology, Faculty of Biological Sciences, University of Concepción, Concepción, Chile
| | - Paul Simion
- Institut des Sciences de l’Evolution de Montpellier, ISEM, Univ Montpellier, CNRS, IRD, EPHE, Université Montpellier, UMR5554 Montpellier, France
| | - Stéphanie Ventéo
- Institute for Neurosciences of Montpellier, Institut National de la Santé et de la Recherche Médicale, U1051 Montpellier, France
| | - Jean-Yves Sire
- Institut de Biologie Paris-Seine, Université Pierre et Marie Curie, UMR7138 Evolution Paris-Seine, Paris, France
| | - Sylvain Marcellini
- Laboratory of Development and Evolution, Department of Cell Biology, Faculty of Biological Sciences, University of Concepción, Concepción, Chile
| | - Mélanie Debiais-Thibaud
- Institut des Sciences de l’Evolution de Montpellier, ISEM, Univ Montpellier, CNRS, IRD, EPHE, Université Montpellier, UMR5554 Montpellier, France
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10
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Abstract
In this review, classical data on the early steps in human odontogenesis are summarized and updated with specific insights into the development of the upper and lower embryonic jaws to help in understanding some oral pathologies. The initial step of human odontogenesis is classically characterized by two parallel horseshoe-shaped epithelial laminae. These originate from the oral epithelium and an ingrowth into the jaw mesenchyme: the internal dental lamina gives rise to deciduous tooth primordia, while the external vestibular lamina represents the developmental base of the oral vestibule. However, a more complex situation was revealed by recent studies combining analyses of the dental and adjacent oral epithelia on histological sections and computer-aided three-dimensional (3D) reconstructions during the 2nd month of human embryonic development. The dental epithelium forms a mound, where swellings appear later, corresponding to the individual primordia of deciduous teeth. External to the developing deciduous dentition, the 3D reconstructions do not show any continuous vestibular lamina but instead a complex of discontinuous epithelial bulges and ridges. The patterns of these epithelial structures and their relationship to the dental epithelium differ not only between the upper and lower jaws but also between the lip and cheek segments in each jaw. Knowledge of early odontogenesis may help in understanding some oral pathologies. For example, the human lateral incisor has a dual origin: it arises in the area of fusion between the medial nasal and maxillary facial processes and involves material from these two regions. Such a dual origin at the site of fusion of facial processes represents a predisposition to developmental vulnerability for the upper lateral incisor, resulting in its frequent anomalies (absence, hypoplasia, duplication), especially in patients with a cleft lip and/or jaw. Other pathologies, such as a minute supernumerary tooth, desmoplastic ameloblastoma or extraosseous odontogenic cysts are located external to the upper or lower dentition, and might be derived from structures that transiently appear during early development of the oral vestibule in humans.
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Affiliation(s)
- Maria Hovorakova
- Institute of Experimental Medicinethe Czech Academy of SciencesPragueCzech Republic
| | - Herve Lesot
- Institute of Animal Physiology and Geneticsthe Czech Academy of SciencesBrnoCzech Republic
| | - Miroslav Peterka
- Institute of Experimental Medicinethe Czech Academy of SciencesPragueCzech Republic
- Institute of AnatomyFirst Faculty of MedicineCharles UniversityPragueCzech Republic
| | - Renata Peterkova
- Institute of Experimental Medicinethe Czech Academy of SciencesPragueCzech Republic
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Cleves PA, Hart JC, Agoglia RM, Jimenez MT, Erickson PA, Gai L, Miller CT. An intronic enhancer of Bmp6 underlies evolved tooth gain in sticklebacks. PLoS Genet 2018; 14:e1007449. [PMID: 29902209 PMCID: PMC6019817 DOI: 10.1371/journal.pgen.1007449] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 06/26/2018] [Accepted: 05/25/2018] [Indexed: 12/30/2022] Open
Abstract
Threespine stickleback fish offer a powerful system to dissect the genetic basis of morphological evolution in nature. Marine sticklebacks have repeatedly invaded and adapted to numerous freshwater environments throughout the Northern hemisphere. In response to new diets in freshwater habitats, changes in craniofacial morphology, including heritable increases in tooth number, have evolved in derived freshwater populations. Using a combination of quantitative genetics and genome resequencing, here we fine-mapped a quantitative trait locus (QTL) regulating evolved tooth gain to a cluster of ten QTL-associated single nucleotide variants, all within intron four of Bone Morphogenetic Protein 6 (Bmp6). Transgenic reporter assays revealed this intronic region contains a tooth enhancer. We induced mutations in Bmp6, revealing required roles for survival, growth, and tooth patterning. Transcriptional profiling of Bmp6 mutant dental tissues identified significant downregulation of a set of genes whose orthologs were previously shown to be expressed in quiescent mouse hair stem cells. Collectively these data support a model where mutations within a Bmp6 intronic tooth enhancer contribute to evolved tooth gain, and suggest that ancient shared genetic circuitry regulates the regeneration of diverse vertebrate epithelial appendages including mammalian hair and fish teeth.
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Affiliation(s)
- Phillip A. Cleves
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley CA, United States of America
| | - James C. Hart
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley CA, United States of America
| | - Rachel M. Agoglia
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley CA, United States of America
| | - Monica T. Jimenez
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley CA, United States of America
| | - Priscilla A. Erickson
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley CA, United States of America
| | - Linda Gai
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley CA, United States of America
| | - Craig T. Miller
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley CA, United States of America
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12
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Liu H, Jiang J, Gong Q, Tian H, Wang S, Zhang J, Pan Z, Liu X. [Knockdown of MSX2 gene inhibits the expression of enamel matrix proteins and the enamel mineralization in mouse ameloblasts]. Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi 2018; 34:230-236. [PMID: 29773104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Objective To study the effect of muscle segment homeodomain homeobox 2 (MSX2) on the expression of enamel matrix protein and the formation of enamel. Methods Immunohistochemical staining was used to detect the expression of MSX2 in mouse tooth embryos and its localization in ameloblasts. The short hairpin RNA (shRNA) of the MSX2 gene was designed and synthesized, and then the annealed double stranded DNA was constructed into the pGMLV-SC5 RNAi lentivirus vector, and finally it was packaged with lentivirus. The lentivirus was used to infect ameloblasts. Real-time fluorescent quantitative PCR was performed to screen the best interference fragment, and detect the mRNAs of amelogenin (Amelx), ameloblastin (Ambn), enamelin (Enam), amelotin (Amtn) and kallikrein 4 (Klk4). The embryos were isolated for 18.5 days and then infected with RNAi recombinant lentivirus targeting MSX2. The tooth germ was implanted under the renal capsule of the mouse. Ten weeks later, the tissue was harvested to separate and observe the tooth form and contour. Results MSX2 was expressed in the secretory phase and maturation phase of mouse ameloblasts, but the expression signal was weaker in the secretory phase and was stronger in the mature stage. The lentivirus of MSX2-shRNA targeting MSX2 gene we constructed inhibited the expression of Amelx and Klk4 mRNAs. The RNAi lentivirus targeting MSX2 gene infected the tooth enamel and led to a decrease in the degree of enamel mineralization. Conclusion The MSX2 gene is expressed in ameloblasts. The knockdown of MSX2 can inhibit the expression of enamel matrix proteins and the enamel mineralization.
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Affiliation(s)
- Hao Liu
- College of Biological Sciences and Technology, Weifang Medical University, Weifang 261053, China
| | - Jianping Jiang
- Department of Rehabilitation, Weifang Hospital of Traditional Chinese Medicine, Weifang 261041, China
| | - Qi Gong
- College of Biological Sciences and Technology, Weifang Medical University, Weifang 261053, China
| | - Huanbing Tian
- College of Biological Sciences and Technology, Weifang Medical University, Weifang 261053, China
| | - Sheng Wang
- College of Clinical Medicine, Weifang Medical University, Weifang 261053, China
| | - Juanjuan Zhang
- College of Stomatology, Weifang Medical University, Weifang 261053, China
| | - Zhifang Pan
- College of Biological Sciences and Technology, Weifang Medical University, Weifang 261053, China
| | - Xiaoying Liu
- College of Biological Sciences and Technology, Weifang Medical University, Weifang 261053, China. *Corresponding author, E-mail:
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13
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Abstract
We performed a test of how function impacts a genetically programmed process that continues into postnatal life. Using the dentition of the polyphyodont gecko as our model, tooth shedding was recorded longitudinally across the jaw. We compared two time periods: one in which teeth were patterned symmetrically in ovo and a later period when teeth were initiated post-hatching. By pairing shedding events on the right and left sides, we found the patterns of tooth loss are symmetrical and stable between periods, with only subtle deviations. Contralateral tooth positions shed within 3-4 days of each other in most animals (7/10). A minority of animals (3/10) had systematic tooth position shifts between right and left sides, likely due to changes in functional tooth number. Our results suggest that in addition to reproducible organogenesis of individual teeth, there is also a neotenic retention of jaw-wide dental patterning in reptiles. Finer analysis of regional asymmetries revealed changes to which contralateral position shed first, affecting up to one quarter of the jaw (10 tooth positions). Once established, these patterns were retained longitudinally. Taken together, the data support regional and global mechanisms of coordinating tooth cycling post-hatching.
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Affiliation(s)
- Theresa M Grieco
- Department of Oral Health Sciences, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Joy M Richman
- Department of Oral Health Sciences, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
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14
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Marin-Riera M, Moustakas-Verho J, Savriama Y, Jernvall J, Salazar-Ciudad I. Differential tissue growth and cell adhesion alone drive early tooth morphogenesis: An ex vivo and in silico study. PLoS Comput Biol 2018; 14:e1005981. [PMID: 29481561 PMCID: PMC5843354 DOI: 10.1371/journal.pcbi.1005981] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 03/08/2018] [Accepted: 01/15/2018] [Indexed: 11/19/2022] Open
Abstract
From gastrulation to late organogenesis animal development involves many genetic and bio-mechanical interactions between epithelial and mesenchymal tissues. Ectodermal organs, such as hairs, feathers and teeth are well studied examples of organs whose development is based on epithelial-mesenchymal interactions. These develop from a similar primordium through an epithelial folding and its interaction with the mesenchyme. Despite extensive knowledge on the molecular pathways involved, little is known about the role of bio-mechanical processes in the morphogenesis of these organs. We propose a simple computational model for the biomechanics of one such organ, the tooth, and contrast its predictions against cell-tracking experiments, mechanical relaxation experiments and the observed tooth shape changes over developmental time. We found that two biomechanical processes, differential tissue growth and differential cell adhesion, were enough, in the model, for the development of the 3D morphology of the early tooth germ. This was largely determined by the length and direction of growth of the cervical loops, lateral folds of the enamel epithelium. The formation of these cervical loops was found to require accelerated epithelial growth relative to other tissues and their direction of growth depended on specific differential adhesion between the three tooth tissues. These two processes and geometrical constraints in early tooth bud also explained the shape asymmetry between the lateral cervical loops and those forming in the anterior and posterior of the tooth. By performing mechanical perturbations ex vivo and in silico we inferred the distribution and direction of tensile stresses in the mesenchyme that restricted cervical loop lateral growth and forced them to grow downwards. Overall our study suggests detailed quantitative explanations for how bio-mechanical processes lead to specific morphological 3D changes over developmental time.
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Affiliation(s)
- Miquel Marin-Riera
- Department of Genetics and Microbiology, Universitat Autònoma de Barcelona, Barcelona, Spain
- Centre of Excellence in Experimental and Computational Developmental Biology, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- * E-mail:
| | - Jacqueline Moustakas-Verho
- Centre of Excellence in Experimental and Computational Developmental Biology, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Yoland Savriama
- Centre of Excellence in Experimental and Computational Developmental Biology, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Jukka Jernvall
- Centre of Excellence in Experimental and Computational Developmental Biology, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Isaac Salazar-Ciudad
- Department of Genetics and Microbiology, Universitat Autònoma de Barcelona, Barcelona, Spain
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
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15
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Duverger O, Ohara T, Bible PW, Zah A, Morasso MI. DLX3-Dependent Regulation of Ion Transporters and Carbonic Anhydrases is Crucial for Enamel Mineralization. J Bone Miner Res 2017; 32:641-653. [PMID: 27760456 PMCID: PMC11025043 DOI: 10.1002/jbmr.3022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 10/10/2016] [Accepted: 10/14/2016] [Indexed: 12/11/2022]
Abstract
Patients with tricho-dento-osseous (TDO) syndrome, an ectodermal dysplasia caused by mutations in the homeodomain transcription factor DLX3, exhibit enamel hypoplasia and hypomineralization. Here we used a conditional knockout mouse model to investigate the developmental and molecular consequences of Dlx3 deletion in the dental epithelium in vivo. Dlx3 deletion in the dental epithelium resulted in the formation of chalky hypomineralized enamel in all teeth. Interestingly, transcriptomic analysis revealed that major enamel matrix proteins and proteases known to be involved in enamel secretion and maturation were not affected significantly by Dlx3 deletion in the enamel organ. In contrast, expression of several ion transporters and carbonic anhydrases known to play an important role in enamel pH regulation during maturation was significantly affected in enamel organs lacking DLX3. Most of these affected genes showed binding of DLX3 to their proximal promoter as evidenced by chromatin immunoprecipitation sequencing (ChIP-seq) analysis on rat enamel organ. These molecular findings were consistent with altered pH staining evidenced by disruption of characteristic pH oscillations in the enamel. Taken together, these results show that DLX3 is indispensable for the regulation of ion transporters and carbonic anhydrases during the maturation stage of amelogenesis, exerting a crucial regulatory function on pH oscillations during enamel mineralization. © 2016 American Society for Bone and Mineral Research.
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Affiliation(s)
- Olivier Duverger
- Laboratory of Skin Biology, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Takahiro Ohara
- Laboratory of Skin Biology, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Paul W Bible
- Laboratory of Skin Biology, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Angela Zah
- Laboratory of Skin Biology, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Maria I Morasso
- Laboratory of Skin Biology, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health (NIH), Bethesda, MD, USA
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16
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Erickson GM, Zelenitsky DK, Kay DI, Norell MA. Dinosaur incubation periods directly determined from growth-line counts in embryonic teeth show reptilian-grade development. Proc Natl Acad Sci U S A 2017; 114:540-545. [PMID: 28049837 PMCID: PMC5255600 DOI: 10.1073/pnas.1613716114] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Birds stand out from other egg-laying amniotes by producing relatively small numbers of large eggs with very short incubation periods (average 11-85 d). This aspect promotes high survivorship by limiting exposure to predation and environmental perturbation, allows for larger more fit young, and facilitates rapid attainment of adult size. Birds are living dinosaurs; their rapid development has been considered to reflect the primitive dinosaurian condition. Here, nonavian dinosaurian incubation periods in both small and large ornithischian taxa are empirically determined through growth-line counts in embryonic teeth. Our results show unexpectedly slow incubation (2.8 and 5.8 mo) like those of outgroup reptiles. Developmental and physiological constraints would have rendered tooth formation and incubation inherently slow in other dinosaur lineages and basal birds. The capacity to determine incubation periods in extinct egg-laying amniotes has implications for dinosaurian embryology, life history strategies, and survivorship across the Cretaceous-Paleogene mass extinction event.
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Affiliation(s)
- Gregory M Erickson
- Department of Biological Science, Florida State University, Tallahassee, FL 32306-4295;
| | - Darla K Zelenitsky
- Department of Geoscience, University of Calgary, Calgary, AB, Canada T2N 1N4
| | - David Ian Kay
- Department of Biological Science, Florida State University, Tallahassee, FL 32306-4295
| | - Mark A Norell
- Division of Paleontology, American Museum of Natural History, New York, NY 10024
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17
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Couly G, Nicot R, Kverneland B, Ferri J, Levaillant JM. Fetal dental panorama on three-dimensional ultrasound imaging. Ultrasound Obstet Gynecol 2016; 48:541-543. [PMID: 27153297 DOI: 10.1002/uog.15957] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 04/10/2016] [Accepted: 04/29/2016] [Indexed: 06/05/2023]
Affiliation(s)
- G Couly
- Center for Woman and Fetal Imaging, Créteil, France
| | - R Nicot
- Center for Woman and Fetal Imaging, Créteil, France.
- University of Lille, Department of Oral and Maxillofacial Surgery, CHU Lille, Lille, France.
| | - B Kverneland
- Department of Maxillofacial Surgery, Necker Enfants Malades University Hospital, Paris, France
| | - J Ferri
- University of Lille, Department of Oral and Maxillofacial Surgery, CHU Lille, Lille, France
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18
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Dental Growth and Development. Pediatr Dent 2016; 38:413. [PMID: 27931485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
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19
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Ellis NA, Donde NN, Miller CT. Early development and replacement of the stickleback dentition. J Morphol 2016; 277:1072-83. [PMID: 27145214 PMCID: PMC5298556 DOI: 10.1002/jmor.20557] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 04/12/2016] [Accepted: 04/17/2016] [Indexed: 11/09/2022]
Abstract
Teeth have long served as a model system to study basic questions about vertebrate organogenesis, morphogenesis, and evolution. In nonmammalian vertebrates, teeth typically regenerate throughout adult life. Fish have evolved a tremendous diversity in dental patterning in both their oral and pharyngeal dentitions, offering numerous opportunities to study how morphology develops, regenerates, and evolves in different lineages. Threespine stickleback fish (Gasterosteus aculeatus) have emerged as a new system to study how morphology evolves, and provide a particularly powerful system to study the development and evolution of dental morphology. Here, we describe the oral and pharyngeal dentitions of stickleback fish, providing additional morphological, histological, and molecular evidence for homology of oral and pharyngeal teeth. Focusing on the ventral pharyngeal dentition in a dense developmental time course of lab-reared fish, we describe the temporal and spatial consensus sequence of early tooth formation. Early in development, this sequence is highly stereotypical and consists of seventeen primary teeth forming the early tooth field, followed by the first tooth replacement event. Comparing this detailed morphological and ontogenetic sequence to that described in other fish reveals that major changes to how dental morphology arises and regenerates have evolved across different fish lineages. J. Morphol. 277:1072-1083, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Nicholas A. Ellis
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley CA, 94720, USA
| | - Nikunj N. Donde
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley CA, 94720, USA
| | - Craig T. Miller
- Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley CA, 94720, USA
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20
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Trubiani O, Orsini G, Caputi S, Piatelli A. Adult Mesenchymal Stem Cells in Dental Research: A New Approach for Tissue Engineering. Int J Immunopathol Pharmacol 2016; 19:451-60. [PMID: 17026831 DOI: 10.1177/039463200601900301] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Many adult tissues contain a population of stem cells that have the ability to regenerate after trauma, disease or aging. Recently, there has been great interest in mesenchymal stem cells and their roles in maintaining the physiological structure of tissues. The studies on stem cells are thought to be very important and, in fact, it has been shown that this cell population can be expanded ex vivo to regenerate tissues not only of the mesenchymal lineage, such as intervertebral disc cartilage, bone and tooth-associated tissues, but also other types of tissues. Several studies have focused on the identification of odontogenic progenitors from oral tissues, and it has been shown that the mesenchymal stem cells obtained from periodontal ligament and dental pulp could have similar morphological and phenotypical features of the bone marrow mesenchymal cells. In fact a population of homogeneous human mesenchymal stem cells derived from periodontal ligament and dental pulp, and proliferating in culture with a well-spread morphology, can be recovered and characterized. Since these cells are considered as candidates for regenerative medicine, the knowledge of the cell differentiation mechanisms is imperative for the development of predictable techniques in implant dentistry, oral surgery and maxillo-facial reconstruction. Thus, future research efforts might be focused on the potential use of this cell population in tissue engineering. Further studies will be carried out to elucidate the molecular mechanisms involved in their maintenance and differentiation in vitro and in vivo.
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Affiliation(s)
- O Trubiani
- Department of Stomatology and Oral Science, Ce.SI. Foundation G. d'Annunzio, Chieti, Italy
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21
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Shi L, Li L, Wang D, Li S, Chen Z, An Z. Spatiotemporal expression of caveolin-1 and EMMPRIN during mouse tooth development. J Mol Histol 2016; 47:337-44. [PMID: 27075451 DOI: 10.1007/s10735-016-9675-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Accepted: 04/06/2016] [Indexed: 12/31/2022]
Abstract
Caveolin-1 is a scaffolding protein involved in the formation of cholesterol-rich caveolae lipid rafts within the plasma membrane and is capable of collecting signaling molecules into the caveolae and regulating their activity, including extracellular matrix metalloproteinase inducer (EMMPRIN). However, detailed expression patterns of caveolin-1 and EMMPRIN in the developing dental germ are largely unknown. The present study investigated the expression patterns of caveolin-1 and EMMPRIN in the developing mouse tooth germ by immunohistochemistry and real-time polymerase chain reaction. At the bud stage, caveolin-1 expression was initiated in the epithelium bud and mesenchymal cells, while EMMPRIN was weakly expressed at this stage. At the cap stage, caveolin-1 protein was located in the lingual part of the tooth germ; however, EMMPRIN protein was located in the labial part. From the bell stage to 2 days postnatal, caveolin-1 expression was detected in the ameloblasts and cervical loop area; with EMMPRIN expression in the ameloblasts and odontoblasts. Real-time polymerase chain reaction results showed that both caveolin-1 and EMMPRIN mRNA levels increased gradually with progression of developmental stages, and peaked at day two postnatal. The current finding suggests that both caveolin-1 and EMMPRIN take part in mouse tooth development, especially in the differentiation and organization of odontogenic tissues.
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Affiliation(s)
- Lu Shi
- Henan Provincial Key Laboratory of Oral Biomedicine, School of Stomatology, Zhengzhou University, 79 Zhongyuandong Road, Zhengzhou, 450000, Henan, People's Republic of China.
| | - Lingyun Li
- Henan Provincial Key Laboratory of Oral Biomedicine, School of Stomatology, Zhengzhou University, 79 Zhongyuandong Road, Zhengzhou, 450000, Henan, People's Republic of China
| | - Ding Wang
- Henan Provincial Key Laboratory of Oral Biomedicine, School of Stomatology, Zhengzhou University, 79 Zhongyuandong Road, Zhengzhou, 450000, Henan, People's Republic of China
| | - Shu Li
- Shandong Provincial Key Laboratory of Oral Biomedicine, School and Hospital of Stomatology, Shandong University, 44-1 Wenhuaxi Road, Jinan, 250012, Shandong, People's Republic of China
| | - Zhi Chen
- Key Lab for Oral Biomedical Engineering, Ministry of Education, School of Stomatology, Wuhan University, Wuhan, People's Republic of China
| | - Zhengwen An
- Craniofacial Development and Stem Cell Biology, Floor 27 Guy's Hospital Dental Institute, King's College London, London, SE1 9RT, UK
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22
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Debiais-Thibaud M, Chiori R, Enault S, Oulion S, Germon I, Martinand-Mari C, Casane D, Borday-Birraux V. Tooth and scale morphogenesis in shark: an alternative process to the mammalian enamel knot system. BMC Evol Biol 2015; 15:292. [PMID: 26704180 PMCID: PMC4690397 DOI: 10.1186/s12862-015-0557-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 12/06/2015] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND The gene regulatory network involved in tooth morphogenesis has been extremely well described in mammals and its modeling has allowed predictions of variations in regulatory pathway that may have led to evolution of tooth shapes. However, very little is known outside of mammals to understand how this regulatory framework may also account for tooth shape evolution at the level of gnathostomes. In this work, we describe expression patterns and proliferation/apoptosis assays to uncover homologous regulatory pathways in the catshark Scyliorhinus canicula. RESULTS Because of their similar structural and developmental features, gene expression patterns were described over the four developmental stages of both tooth and scale buds in the catshark. These gene expression patterns differ from mouse tooth development, and discrepancies are also observed between tooth and scale development within the catshark. However, a similar nested expression of Shh and Fgf suggests similar signaling involved in morphogenesis of all structures, although apoptosis assays do not support a strictly equivalent enamel knot system in sharks. Similarities in the topology of gene expression pattern, including Bmp signaling pathway, suggest that mouse molar development is more similar to scale bud development in the catshark. CONCLUSIONS These results support the fact that no enamel knot, as described in mammalian teeth, can be described in the morphogenesis of shark teeth or scales. However, homologous signaling pathways are involved in growth and morphogenesis with variations in their respective expression patterns. We speculate that variations in this topology of expression are also a substrate for tooth shape evolution, notably in regulating the growth axis and symmetry of the developing structure.
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Affiliation(s)
- Mélanie Debiais-Thibaud
- Institut des Sciences de l'Evolution de Montpellier, UMR5554, Université Montpellier, CNRS, IRD, EPHE, Montpellier, France.
| | - Roxane Chiori
- Evolution, Génomes, Comportement & Ecologie, CNRS, IRD, Univ.Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette, France.
- Université Paris Diderot, Sorbonne Paris Cité, Paris, France.
| | - Sébastien Enault
- Institut des Sciences de l'Evolution de Montpellier, UMR5554, Université Montpellier, CNRS, IRD, EPHE, Montpellier, France.
| | - Silvan Oulion
- Institut des Sciences de l'Evolution de Montpellier, UMR5554, Université Montpellier, CNRS, IRD, EPHE, Montpellier, France.
| | - Isabelle Germon
- Evolution, Génomes, Comportement & Ecologie, CNRS, IRD, Univ.Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette, France.
| | - Camille Martinand-Mari
- Institut des Sciences de l'Evolution de Montpellier, UMR5554, Université Montpellier, CNRS, IRD, EPHE, Montpellier, France.
| | - Didier Casane
- Evolution, Génomes, Comportement & Ecologie, CNRS, IRD, Univ.Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette, France.
- Université Paris Diderot, Sorbonne Paris Cité, Paris, France.
| | - Véronique Borday-Birraux
- Evolution, Génomes, Comportement & Ecologie, CNRS, IRD, Univ.Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette, France.
- Université Paris Diderot, Sorbonne Paris Cité, Paris, France.
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23
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Abstract
In many aquatic vertebrates, including bony and cartilaginous fishes, teeth and taste buds colocalize on jaw elements. In these animals, taste buds are renewed continuously throughout life, whereas teeth undergo cycled whole-organ replacement by various means. Recently, studies of cichlid fishes have yielded new insights into the development and regeneration of these dental and sensory oral organs. Tooth and taste bud densities covary positively across species with different feeding strategies, controlled by common regions of the genome and integrated molecular signals. Developing teeth and taste buds share a bipotent epithelium during early patterning stages, from which dental and taste fields are specified. Moreover, these organs share a common epithelial ribbon that supports label-retaining cells during later stages of regeneration. During both patterning and regeneration stages, dental organs can be converted to taste bud fate by manipulation of BMP signaling. These observations highlight a surprising long-term plasticity between dental and sensory organ types. Here, we review these findings and discuss the implications of developmental plasticity that spans the continuum of craniofacial organ patterning and regeneration.
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Affiliation(s)
- J Todd Streelman
- School of Biology, Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia, USA.
| | - Ryan F Bloomquist
- School of Biology, Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Teresa E Fowler
- School of Biology, Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia, USA
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24
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Zhou C, Yang G, Chen M, He L, Xiang L, Ricupero C, Mao JJ, Ling J. Lhx6 and Lhx8: cell fate regulators and beyond. FASEB J 2015; 29:4083-91. [PMID: 26148970 PMCID: PMC4566936 DOI: 10.1096/fj.14-267500] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Accepted: 06/22/2015] [Indexed: 12/11/2022]
Abstract
As transcription factors of the lines (LIN)-11/Islet (Isl)-1/mitosis entry checkpoint (MEC)-3 (LIM)-homeobox subfamily, LIM homeobox (Lhx)6 and -8 are remarkably conserved and involved in the morphogenesis of multiple organ systems. Lhx6 and -8 play overlapping and distinctive roles, but in general act as cell fate mediators and in turn are regulated by several transcriptional factors, such as sonic hedgehog, fibroblast growth factors, and wingless-int (Wnt)/β-catenin. In this review, we first summarize Lhx6 and -8 distributions in development and then explore how Lhx6 and -8 act as transcription factors and coregulators of cell lineage specification. Known Lhx6 and -8 functions and targets are outlined in neurogenesis, craniofacial development, and germ cell differentiation. The underlying mechanisms of Lhx6 and -8 in regulating cell fate remain elusive. Whether Lhx6 and -8 affect functions in tissues and organs other than neural, craniofacial, oocytes, and germ cells is largely unexplored. Taken together, Lhx6 and -8 are important regulators of cell lineage specification and may act as one of the pivotal mediators of stem cell fate. Undoubtedly, future investigations of Lhx6 and -8 biology will continue to yield fascinating insights into tissue development and homeostasis, in addition to their putative roles in tissue regeneration and ageing.
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Affiliation(s)
- Chen Zhou
- *Center for Craniofacial Regeneration, Columbia University Medical Center, New York, New York, USA; Guanghua School of Stomatology, Hospital of Stomatology, and Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Guodong Yang
- *Center for Craniofacial Regeneration, Columbia University Medical Center, New York, New York, USA; Guanghua School of Stomatology, Hospital of Stomatology, and Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Mo Chen
- *Center for Craniofacial Regeneration, Columbia University Medical Center, New York, New York, USA; Guanghua School of Stomatology, Hospital of Stomatology, and Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Ling He
- *Center for Craniofacial Regeneration, Columbia University Medical Center, New York, New York, USA; Guanghua School of Stomatology, Hospital of Stomatology, and Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Lusai Xiang
- *Center for Craniofacial Regeneration, Columbia University Medical Center, New York, New York, USA; Guanghua School of Stomatology, Hospital of Stomatology, and Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Christopher Ricupero
- *Center for Craniofacial Regeneration, Columbia University Medical Center, New York, New York, USA; Guanghua School of Stomatology, Hospital of Stomatology, and Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Jeremy J Mao
- *Center for Craniofacial Regeneration, Columbia University Medical Center, New York, New York, USA; Guanghua School of Stomatology, Hospital of Stomatology, and Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Junqi Ling
- *Center for Craniofacial Regeneration, Columbia University Medical Center, New York, New York, USA; Guanghua School of Stomatology, Hospital of Stomatology, and Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
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25
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Underwood CJ, Johanson Z, Welten M, Metscher B, Rasch LJ, Fraser GJ, Smith MM. Development and evolution of dentition pattern and tooth order in the skates and rays (batoidea; chondrichthyes). PLoS One 2015; 10:e0122553. [PMID: 25874547 PMCID: PMC4398376 DOI: 10.1371/journal.pone.0122553] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 02/23/2015] [Indexed: 11/20/2022] Open
Abstract
Shark and ray (elasmobranch) dentitions are well known for their multiple generations of teeth, with isolated teeth being common in the fossil record. However, how the diverse dentitions characteristic of elasmobranchs form is still poorly understood. Data on the development and maintenance of the dental patterning in this major vertebrate group will allow comparisons to other morphologically diverse taxa, including the bony fishes, in order to identify shared pattern characters for the vertebrate dentition as a whole. Data is especially lacking from the Batoidea (skates and rays), hence our objective is to compile data on embryonic and adult batoid tooth development contributing to ordering of the dentition, from cleared and stained specimens and micro-CT scans, with 3D rendered models. We selected species (adult and embryonic) spanning phylogenetically significant batoid clades, such that our observations may raise questions about relationships within the batoids, particularly with respect to current molecular-based analyses. We include developmental data from embryos of recent model organisms Leucoraja erinacea and Raja clavata to evaluate the earliest establishment of the dentition. Characters of the batoid dentition investigated include alternate addition of teeth as offset successional tooth rows (versus single separate files), presence of a symphyseal initiator region (symphyseal tooth present, or absent, but with two parasymphyseal teeth) and a restriction to tooth addition along each jaw reducing the number of tooth families, relative to addition of successor teeth within each family. Our ultimate aim is to understand the shared characters of the batoids, and whether or not these dental characters are shared more broadly within elasmobranchs, by comparing these to dentitions in shark outgroups. These developmental morphological analyses will provide a solid basis to better understand dental evolution in these important vertebrate groups as well as the general plesiomorphic vertebrate dental condition.
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Affiliation(s)
- Charlie J. Underwood
- Department of Earth and Planetary Sciences, Birkbeck, University of London, Malet Street, London WC1E 7HX, United Kingdom
- * E-mail:
| | - Zerina Johanson
- Department of Earth Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, United Kingdom
| | - Monique Welten
- Department of Earth Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, United Kingdom
| | - Brian Metscher
- Department of Theoretical Biology, University of Vienna, Althanstrasse 14, 1090 Wien, Austria
| | - Liam J. Rasch
- Department of Animal and Plant Sciences, The University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Gareth J. Fraser
- Department of Animal and Plant Sciences, The University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Moya Meredith Smith
- Department of Earth Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, United Kingdom
- King's College London, Dental Institute, Craniofacial Development, London SE1 9RT, United Kingdom
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Jeong JO, Wang G, Jeong SJ, Choi BD, Lee HY, Jeong MJ. Function of Secretory Leukocyte Protease Inhibitor (SLPI) in Odontoblast During Mouse Tooth Development. J Nanosci Nanotechnol 2015; 15:120-124. [PMID: 26328314 DOI: 10.1166/jnn.2015.8384] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Secretory leuckocyte protease inhibitor (SLPI) is thought as a regulating protein on the synthesis and degradation of matrix proteins. But there was no report of expression and function of SLPI on the tooth development, especially on the odontoblasts. As observed by in-situ hybridization and immunohistochemical analysis, SLPI was expressed in odontoblasts and predentin on post-natal day 4 (PN4). On PN10, SLPI was observed under the dentin and apical region including odontoblasts processes. Further, on PN15, expression of SLPI was the same pattern compared to PN10. SLPI was expressed under layer of the odontoblasts and in odontoblasts on PN20. Matrix metalloproteinase-2 (MMP-2) and -9 levels in SLPI/MDPC-23 cells were higher than that of the MDPC-23 cells. The gene expression of SLPI, bone sialoprotein (BSP), osteocalcin (OCN), osteonectin (ON), and collagen type I (Col I) was higher in SLPI/MDPC-23 than that of MDPC-23 cells and the expression of dentin sialophosphoprotein (DSPP) was lower in SLPI/MDPC-23. Taken together, our results suggest that SLPI may be a MMP-2 and -9 regulating molecule in odontoblasts during dentin matrix formation and acts as a signaling molecule for dentin matrix related proteins during odontoblasts differentiation and mineralization.
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Yuan G, Yang G, Zheng Y, Zhu X, Chen Z, Zhang Z, Chen Y. The non-canonical BMP and Wnt/β-catenin signaling pathways orchestrate early tooth development. Development 2015; 142:128-39. [PMID: 25428587 PMCID: PMC4299140 DOI: 10.1242/dev.117887] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 10/24/2014] [Indexed: 12/31/2022]
Abstract
BMP and Wnt signaling pathways play a crucial role in organogenesis, including tooth development. Despite extensive studies, the exact functions, as well as if and how these two pathways act coordinately in regulating early tooth development, remain elusive. In this study, we dissected regulatory functions of BMP and Wnt pathways in early tooth development using a transgenic noggin (Nog) overexpression model (K14Cre;pNog). It exhibits early arrested tooth development, accompanied by reduced cell proliferation and loss of odontogenic fate marker Pitx2 expression in the dental epithelium. We demonstrated that overexpression of Nog disrupted BMP non-canonical activity, which led to a dramatic reduction of cell proliferation rate but did not affect Pitx2 expression. We further identified a novel function of Nog by inhibiting Wnt/β-catenin signaling, causing loss of Pitx2 expression. Co-immunoprecipitation and TOPflash assays revealed direct binding of Nog to Wnts to functionally prevent Wnt/β-catenin signaling. In situ PLA and immunohistochemistry on Nog mutants confirmed in vivo interaction between endogenous Nog and Wnts and modulation of Wnt signaling by Nog in tooth germs. Genetic rescue experiments presented evidence that both BMP and Wnt signaling pathways contribute to cell proliferation regulation in the dental epithelium, with Wnt signaling also controlling the odontogenic fate. Reactivation of both BMP and Wnt signaling pathways, but not of only one of them, rescued tooth developmental defects in K14Cre;pNog mice, in which Wnt signaling can be substituted by transgenic activation of Pitx2. Our results reveal the orchestration of non-canonical BMP and Wnt/β-catenin signaling pathways in the regulation of early tooth development.
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Affiliation(s)
- Guohua Yuan
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079, China Department of Cell and Molecular Biology, Tulane University, New Orleans, LA 70118, USA
| | - Guobin Yang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079, China Department of Cell and Molecular Biology, Tulane University, New Orleans, LA 70118, USA
| | - Yuqian Zheng
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA 70118, USA Department of Periodontology, College of Stomatology, Fujian Medical University, Fuzhou 350002, China
| | - Xiaojing Zhu
- Institute of Developmental and Regenerative Biology, College of Life and Environmental Science, Hangzhou Normal University, Hangzhou 311121, China
| | - Zhi Chen
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079, China
| | - Zunyi Zhang
- Institute of Developmental and Regenerative Biology, College of Life and Environmental Science, Hangzhou Normal University, Hangzhou 311121, China
| | - YiPing Chen
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA 70118, USA
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Djordjevic D, Yang A, Zadoorian A, Rungrugeecharoen K, Ho JWK. How difficult is inference of mammalian causal gene regulatory networks? PLoS One 2014; 9:e111661. [PMID: 25369032 PMCID: PMC4219746 DOI: 10.1371/journal.pone.0111661] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Accepted: 09/29/2014] [Indexed: 01/20/2023] Open
Abstract
Gene regulatory networks (GRNs) play a central role in systems biology, especially in the study of mammalian organ development. One key question remains largely unanswered: Is it possible to infer mammalian causal GRNs using observable gene co-expression patterns alone? We assembled two mouse GRN datasets (embryonic tooth and heart) and matching microarray gene expression profiles to systematically investigate the difficulties of mammalian causal GRN inference. The GRNs were assembled based on pieces of experimental genetic perturbation evidence from manually reading primary research articles. Each piece of perturbation evidence records the qualitative change of the expression of one gene following knock-down or over-expression of another gene. Our data have thorough annotation of tissue types and embryonic stages, as well as the type of regulation (activation, inhibition and no effect), which uniquely allows us to estimate both sensitivity and specificity of the inference of tissue specific causal GRN edges. Using these unprecedented datasets, we found that gene co-expression does not reliably distinguish true positive from false positive interactions, making inference of GRN in mammalian development very difficult. Nonetheless, if we have expression profiling data from genetic or molecular perturbation experiments, such as gene knock-out or signalling stimulation, it is possible to use the set of differentially expressed genes to recover causal regulatory relationships with good sensitivity and specificity. Our result supports the importance of using perturbation experimental data in causal network reconstruction. Furthermore, we showed that causal gene regulatory relationship can be highly cell type or developmental stage specific, suggesting the importance of employing expression profiles from homogeneous cell populations. This study provides essential datasets and empirical evidence to guide the development of new GRN inference methods for mammalian organ development.
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Affiliation(s)
- Djordje Djordjevic
- Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia
- The University of New South Wales, Sydney, New South Wales, Australia
| | - Andrian Yang
- Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia
| | - Armella Zadoorian
- Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia
- The University of New South Wales, Sydney, New South Wales, Australia
| | - Kevin Rungrugeecharoen
- Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia
- The University of New South Wales, Sydney, New South Wales, Australia
| | - Joshua W. K. Ho
- Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia
- The University of New South Wales, Sydney, New South Wales, Australia
- * E-mail:
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Reibring CG, El Shahawy M, Hallberg K, Kannius-Janson M, Nilsson J, Parkkila S, Sly WS, Waheed A, Linde A, Gritli-Linde A. Expression patterns and subcellular localization of carbonic anhydrases are developmentally regulated during tooth formation. PLoS One 2014; 9:e96007. [PMID: 24789143 PMCID: PMC4006843 DOI: 10.1371/journal.pone.0096007] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Accepted: 04/01/2014] [Indexed: 02/06/2023] Open
Abstract
Carbonic anhydrases (CAs) play fundamental roles in several physiological events, and emerging evidence points at their involvement in an array of disorders, including cancer. The expression of CAs in the different cells of teeth is unknown, let alone their expression patterns during odontogenesis. As a first step towards understanding the role of CAs during odontogenesis, we used immunohistochemistry, histochemistry and in situ hybridization to reveal hitherto unknown dynamic distribution patterns of eight CAs in mice. The most salient findings include expression of CAII/Car2 not only in maturation-stage ameloblasts (MA) but also in the papillary layer, dental papilla mesenchyme, odontoblasts and the epithelial rests of Malassez. We uncovered that the latter form lace-like networks around incisors; hitherto these have been known to occur only in molars. All CAs studied were produced by MA, however CAIV, CAIX and CARPXI proteins were distinctly enriched in the ruffled membrane of the ruffled MA but exhibited a homogeneous distribution in smooth-ended MA. While CAIV, CAVI/Car6, CAIX, CARPXI and CAXIV were produced by all odontoblasts, CAIII distribution displayed a striking asymmetry, in that it was virtually confined to odontoblasts in the root of molars and root analog of incisors. Remarkably, from initiation until near completion of odontogenesis and in several other tissues, CAXIII localized mainly in intracellular punctae/vesicles that we show to overlap with LAMP-1- and LAMP-2-positive vesicles, suggesting that CAXIII localizes within lysosomes. We showed that expression of CAs in developing teeth is not confined to cells involved in biomineralization, pointing at their participation in other biological events. Finally, we uncovered novel sites of CA expression, including the developing brain and eye, the olfactory epithelium, melanoblasts, tongue, notochord, nucleus pulposus and sebaceous glands. Our study provides important information for future single or multiple gene targeting strategies aiming at deciphering the function of CAs during odontogenesis.
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Affiliation(s)
- Claes-Göran Reibring
- Department of Oral Biochemistry, Sahlgrenska Academy at the University of Gothenburg, Göteborg, Sweden
| | - Maha El Shahawy
- Department of Oral Biochemistry, Sahlgrenska Academy at the University of Gothenburg, Göteborg, Sweden
- Department of Oral Biology, Minia University, Minia, Egypt
| | - Kristina Hallberg
- Department of Oral Biochemistry, Sahlgrenska Academy at the University of Gothenburg, Göteborg, Sweden
| | - Marie Kannius-Janson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Göteborg, Sweden
| | - Jeanette Nilsson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Göteborg, Sweden
| | - Seppo Parkkila
- School of Medicine and BioMediTech, University of Tampere and Fimlab, Tampere University Hospital, Tampere, Finland
| | - William S. Sly
- Saint Louis University School of Medicine, Saint Louis, Missouri, United States of America
| | - Abdul Waheed
- Saint Louis University School of Medicine, Saint Louis, Missouri, United States of America
| | - Anders Linde
- Department of Oral Biochemistry, Sahlgrenska Academy at the University of Gothenburg, Göteborg, Sweden
| | - Amel Gritli-Linde
- Department of Oral Biochemistry, Sahlgrenska Academy at the University of Gothenburg, Göteborg, Sweden
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Didilescu AC, Pop F, Rusu MC. c-kit positive cells and networks in tooth germs of human midterm fetuses. Ann Anat 2013; 195:581-5. [PMID: 23932767 DOI: 10.1016/j.aanat.2013.06.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 04/02/2013] [Accepted: 06/04/2013] [Indexed: 12/15/2022]
Abstract
Numerous studies have attempted to characterize the dental pulp stem cells. However, studies performed on prenatal human tissues have not been performed to evaluate the in situ characterization and topography of progenitor cells. We aimed to perform such a study using of antibodies for CD117/c-kit and multiplex antibody for Ki67+ caspase 3. Antibodies were applied on samples dissected from five human midterm fetuses. Positive CD117/c-kit labeling was found in mesenchymal derived tissues, such as the dental follicle and the dental papilla. The epithelial tissues, that is, dental lamina, enamel organ and oral epithelia, also displayed isolated progenitor cells which were CD117/c-kit positive. Interestingly, CD117/c-kit positive cells of mesenchymal derived tissues extended multiple prolongations building networks; the most consistent of such networks were those of the dental follicle and the perivascular networks of the dental papilla. However, the mantle of the dental papilla was also positive for CD117/c-kit positive stromal networks. The CD117/c-kit cell populations building networks appeared mostly with a Ki67 negative phenotype. The results suggest that CD117/c-kit progenitor cells of the prenatal tooth germ tissues might be involved in intercellular signaling.
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Affiliation(s)
- Andreea Cristiana Didilescu
- Division of Embryology, Faculty of Dental Medicine, "Carol Davila" University of Medicine and Pharmacy, 8, Boulevard Eroilor Sanitari, 050474 Bucharest, Romania.
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Li L, Wang Y, Lin M, Yuan G, Yang G, Zheng Y, Chen Y. Augmented BMPRIA-mediated BMP signaling in cranial neural crest lineage leads to cleft palate formation and delayed tooth differentiation. PLoS One 2013; 8:e66107. [PMID: 23776616 PMCID: PMC3680418 DOI: 10.1371/journal.pone.0066107] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 05/01/2013] [Indexed: 01/11/2023] Open
Abstract
The importance of BMP receptor Ia (BMPRIa) mediated signaling in the development of craniofacial organs, including the tooth and palate, has been well illuminated in several mouse models of loss of function, and by its mutations associated with juvenile polyposis syndrome and facial defects in humans. In this study, we took a gain-of-function approach to further address the role of BMPR-IA-mediated signaling in the mesenchymal compartment during tooth and palate development. We generated transgenic mice expressing a constitutively active form of BmprIa (caBmprIa) in cranial neural crest (CNC) cells that contributes to the dental and palatal mesenchyme. Mice bearing enhanced BMPRIa-mediated signaling in CNC cells exhibit complete cleft palate and delayed odontogenic differentiation. We showed that the cleft palate defect in the transgenic animals is attributed to an altered cell proliferation rate in the anterior palatal mesenchyme and to the delayed palatal elevation in the posterior portion associated with ectopic cartilage formation. Despite enhanced activity of BMP signaling in the dental mesenchyme, tooth development and patterning in transgenic mice appeared normal except delayed odontogenic differentiation. These data support the hypothesis that a finely tuned level of BMPRIa-mediated signaling is essential for normal palate and tooth development.
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Affiliation(s)
- Lu Li
- Department of Cell and Molecular Biology, Tulane University, New Orleans, Louisiana, United States of America
| | - Ying Wang
- Department of Cell and Molecular Biology, Tulane University, New Orleans, Louisiana, United States of America
- Department of Operative Dentistry and Endodontics, College of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi Province, P.R. China
| | - Minkui Lin
- Department of Cell and Molecular Biology, Tulane University, New Orleans, Louisiana, United States of America
- Department of Periodontology, College of Stomatology, Fujian Medical University, Fuzhou, Fujian Province, P.R. China
| | - Guohua Yuan
- Department of Cell and Molecular Biology, Tulane University, New Orleans, Louisiana, United States of America
- Department of Pediatric Dentistry, College of Stomatology, Wuhan University, Wuhan, Hubei Province, P.R. China
| | - Guobin Yang
- Department of Cell and Molecular Biology, Tulane University, New Orleans, Louisiana, United States of America
- Department of Pediatric Dentistry, College of Stomatology, Wuhan University, Wuhan, Hubei Province, P.R. China
| | - Yuqian Zheng
- Department of Cell and Molecular Biology, Tulane University, New Orleans, Louisiana, United States of America
- Department of Periodontology, College of Stomatology, Fujian Medical University, Fuzhou, Fujian Province, P.R. China
| | - YiPing Chen
- Department of Cell and Molecular Biology, Tulane University, New Orleans, Louisiana, United States of America
- * E-mail:
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Liu H, Lin H, Zhang L, Sun Q, Yuan G, Zhang L, Chen S, Chen Z. miR-145 and miR-143 regulate odontoblast differentiation through targeting Klf4 and Osx genes in a feedback loop. J Biol Chem 2013; 288:9261-71. [PMID: 23430263 PMCID: PMC3610997 DOI: 10.1074/jbc.m112.433730] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 01/17/2013] [Indexed: 01/01/2023] Open
Abstract
Dentin tissue is derived from mesenchymal cells induced into the odontoblast lineage. The differentiation of odontoblasts is a complex process regulated by several transcriptional factor signaling transduction pathways. However, post-translational regulation of these factors during dentinogenesis remains unclear. To further explore the mechanisms, we investigated the role of microRNA (miRNA) during odontoblast differentiation. We profiled the miRNA expression pattern during mouse odontoblast differentiation using a microarray assay and identified that miR-145 and miR-143 were down-regulated during this process. In situ hybridization verified that the two miRNAs were gradually decreased during mouse odontoblast differentiation. Loss-of-function and gain-of-function experiments revealed that down-regulation of miR-145 and miR-143 could promote odontoblast differentiation and increased Dspp and Dmp1 expression in mouse primary dental pulp cells and vice versa. We found that miR-145 and miR-143 controlled odontoblast differentiation through several mechanisms. First, KLF4 and OSX bind to their motifs in Dspp and Dmp1 gene promoters and up-regulate their transcription thereby inducing odontoblast differentiation. The miR-145 binds to the 3'-UTRs of Klf4 and Osx genes, inhibiting their expression. Second, KLF4 repressed miR-143 transcription by binding to its motifs in miR-143 regulatory regions as detected by ChIP assay and dual luciferase reporter assay. Third, miR-143 regulates odontoblast differentiation in part through miR-145 pathway. Taken together, we for the first time showed that the miR-143 and miR-145 controlled odontoblast differentiation and dentin formation through KLF4 and OSX transcriptional factor signaling pathways.
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Affiliation(s)
- Huan Liu
- From the State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079, China and
| | - Heng Lin
- From the State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079, China and
| | - Li Zhang
- From the State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079, China and
| | - Qin Sun
- From the State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079, China and
| | - Guohua Yuan
- From the State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079, China and
| | - Lu Zhang
- From the State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079, China and
| | - Shuo Chen
- Department of Developmental Dentistry, The University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Zhi Chen
- From the State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079, China and
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Zhang Z, Gutierrez D, Li X, Bidlack F, Cao H, Wang J, Andrade K, Margolis HC, Amendt BA. The LIM homeodomain transcription factor LHX6: a transcriptional repressor that interacts with pituitary homeobox 2 (PITX2) to regulate odontogenesis. J Biol Chem 2013; 288:2485-500. [PMID: 23229549 PMCID: PMC3554917 DOI: 10.1074/jbc.m112.402933] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 11/29/2012] [Indexed: 11/06/2022] Open
Abstract
LHX6 is a LIM-homeobox transcription factor expressed during embryogenesis; however, the molecular mechanisms regulating LHX6 transcriptional activities are unknown. LHX6 and the PITX2 homeodomain transcription factor have overlapping expression patterns during tooth and craniofacial development, and in this report, we demonstrate new transcriptional mechanisms for these factors. PITX2 and LHX6 are co-expressed in the oral and dental epithelium and epithelial cell lines. Lhx6 expression is increased in Pitx2c transgenic mice and decreased in Pitx2 null mice. PITX2 activates endogenous Lhx6 expression and the Lhx6 promoter, whereas LHX6 represses its promoter activity. Chromatin immunoprecipitation experiments reveal endogenous PITX2 binding to the Lhx6 promoter. LHX6 directly interacts with PITX2 to inhibit PITX2 transcriptional activities and activation of multiple promoters. Bimolecular fluorescence complementation assays reveal an LHX6·PITX2 nuclear interaction in living cells. LHX6 has a dominant repressive effect on the PITX2 synergistic activation with LEF-1 and β-catenin co-factors. Thus, LHX6 acts as a transcriptional repressor and represses the expression of several genes involved in odontogenesis. We have identified specific defects in incisor, molar, mandible, bone, and root development and late stage enamel formation in Lhx6 null mice. Amelogenin and ameloblastin expression is reduced and/or delayed in the Lhx6 null mice, potentially resulting from defects in dentin deposition and ameloblast differentiation. Our results demonstrate that LHX6 regulates cell proliferation in the cervical loop and promotes cell differentiation in the anterior region of the incisor. We demonstrate new molecular mechanisms for LHX6 and an interaction with PITX2 for normal craniofacial and tooth development.
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Affiliation(s)
- Zichao Zhang
- From the Center for Environmental and Genetic Medicine, Institute of Biosciences and Technology, Texas A & M University Health Science Center, Houston, Texas 77030 and
| | - Diana Gutierrez
- From the Center for Environmental and Genetic Medicine, Institute of Biosciences and Technology, Texas A & M University Health Science Center, Houston, Texas 77030 and
| | - Xiao Li
- From the Center for Environmental and Genetic Medicine, Institute of Biosciences and Technology, Texas A & M University Health Science Center, Houston, Texas 77030 and
| | - Felicitas Bidlack
- the Department of Biomineralization, The Forsyth Institute, Boston, Massachusetts 02142
| | - Huojun Cao
- From the Center for Environmental and Genetic Medicine, Institute of Biosciences and Technology, Texas A & M University Health Science Center, Houston, Texas 77030 and
| | - Jianbo Wang
- From the Center for Environmental and Genetic Medicine, Institute of Biosciences and Technology, Texas A & M University Health Science Center, Houston, Texas 77030 and
| | - Kelsey Andrade
- From the Center for Environmental and Genetic Medicine, Institute of Biosciences and Technology, Texas A & M University Health Science Center, Houston, Texas 77030 and
| | - Henry C. Margolis
- the Department of Biomineralization, The Forsyth Institute, Boston, Massachusetts 02142
| | - Brad A. Amendt
- From the Center for Environmental and Genetic Medicine, Institute of Biosciences and Technology, Texas A & M University Health Science Center, Houston, Texas 77030 and
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Zahradnicek O, Horacek I, Tucker AS. Tooth development in a model reptile: functional and null generation teeth in the gecko Paroedura picta. J Anat 2012; 221:195-208. [PMID: 22780101 PMCID: PMC3458625 DOI: 10.1111/j.1469-7580.2012.01531.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2012] [Indexed: 11/29/2022] Open
Abstract
This paper describes tooth development in a basal squamate, Paroedura picta. Due to its reproductive strategy, mode of development and position within the reptiles, this gecko represents an excellent model organism for the study of reptile development. Here we document the dental pattern and development of non-functional (null generation) and functional generations of teeth during embryonic development. Tooth development is followed from initiation to cytodifferentiation and ankylosis, as the tooth germs develop from bud, through cap to bell stages. The fate of the single generation of non-functional (null generation) teeth is shown to be variable, with some teeth being expelled from the oral cavity, while others are incorporated into the functional bone and teeth, or are absorbed. Fate appears to depend on the initiation site within the oral cavity, with the first null generation teeth forming before formation of the dental lamina. We show evidence for a stratum intermedium layer in the enamel epithelium of functional teeth and show that the bicuspid shape of the teeth is created by asymmetrical deposition of enamel, and not by folding of the inner dental epithelium as observed in mammals.
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Affiliation(s)
- Oldrich Zahradnicek
- Department of Zoology, Faculty of Science, Charles University, Prague, Czech Republic.
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Juuri E, Saito K, Ahtiainen L, Seidel K, Tummers M, Hochedlinger K, Klein OD, Thesleff I, Michon F. Sox2+ stem cells contribute to all epithelial lineages of the tooth via Sfrp5+ progenitors. Dev Cell 2012; 23:317-28. [PMID: 22819339 DOI: 10.1016/j.devcel.2012.05.012] [Citation(s) in RCA: 180] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 02/22/2012] [Accepted: 05/18/2012] [Indexed: 12/21/2022]
Abstract
The continuously growing mouse incisor serves as a valuable model to study stem cell regulation during organ renewal. Epithelial stem cells are localized in the proximal end of the incisor in the labial cervical loop. Here, we show that the transcription factor Sox2 is a specific marker for these stem cells. Sox2+ cells became restricted to the labial cervical loop during tooth morphogenesis, and they contributed to the renewal of enamel-producing ameloblasts as well as all other epithelial cell lineages of the tooth. The early progeny of Sox2-positive stem cells transiently expressed the Wnt inhibitor Sfrp5. Sox2 expression was regulated by the tooth initiation marker FGF8 and specific miRNAs, suggesting a fine-tuning to maintain homeostasis of the dental epithelium. The identification of Sox2 as a marker for the dental epithelial stem cells will facilitate further studies on their lineage segregation and differentiation during tooth renewal.
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Affiliation(s)
- Emma Juuri
- Developmental Biology Program, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
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36
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Abstract
Teleost fishes comprise approximately half of all living vertebrates. The extreme range of diversity in teleosts is remarkable, especially, extensive morphological variation in their jaws and dentition. Some of the most unusual dentitions are found among members of the highly derived teleost order Tetraodontiformes, which includes triggerfishes, boxfishes, ocean sunfishes, and pufferfishes. Adult pufferfishes (Tetraodontidae) exhibit a distinctive parrot-like beaked jaw, forming a cutting edge, unlike in any other group of teleosts. Here we show that despite novelty in the structure and development of this "beak," it is initiated by formation of separate first-generation teeth that line the embryonic pufferfish jaw, with timing of development and gene expression patterns conserved from the last common ancestor of osteichthyans. Most of these first-generation larval teeth are lost in development. Continuous tooth replacement proceeds in only four parasymphyseal teeth, as sequentially stacked, multigenerational, jaw-length dentine bands, before development of the functional beak. These data suggest that dental novelties, such as the pufferfish beak, can develop later in ontogeny through modified continuous tooth addition and replacement. We conclude that even highly derived morphological structures like the pufferfish beak form via a conserved developmental bauplan capable of modification during ontogeny by subtle respecification of the developmental module.
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Affiliation(s)
- Gareth J Fraser
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, United Kingdom.
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Rothová M, Peterková R, Tucker AS. Fate map of the dental mesenchyme: dynamic development of the dental papilla and follicle. Dev Biol 2012; 366:244-54. [PMID: 22542602 DOI: 10.1016/j.ydbio.2012.03.018] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 03/01/2012] [Accepted: 03/30/2012] [Indexed: 11/18/2022]
Abstract
At the bud stage of tooth development the neural crest derived mesenchyme condenses around the dental epithelium. As the tooth germ develops and proceeds to the cap stage, the epithelial cervical loops grow and appear to wrap around the condensed mesenchyme, enclosing the cells of the forming dental papilla. We have fate mapped the dental mesenchyme, using in vitro tissue culture combined with vital cell labelling and tissue grafting, and show that the dental mesenchyme is a much more dynamic population then previously suggested. At the bud stage the mesenchymal cells adjacent to the tip of the bud form both the dental papilla and dental follicle. At the early cap stage a small population of highly proliferative mesenchymal cells in close proximity to the inner dental epithelium and primary enamel knot provide the major contribution to the dental papilla. These cells are located between the cervical loops, within a region we have called the body of the enamel organ, and proliferate in concert with the epithelium to create the dental papilla. The condensed dental mesenchymal cells that are not located between the body of the enamel organ, and therefore are at a distance from the primary enamel knot, contribute to the dental follicle, and also the apical part of the papilla, where the roots will ultimately develop. Some cells in the presumptive dental papilla at the cap stage contribute to the follicle at the bell stage, indicating that the dental papilla and dental follicle are still not defined populations at this stage. These lineage-tracing experiments highlight the difficulty of targeting the papilla and presumptive odontoblasts at early stages of tooth development. We show that at the cap stage, cells destined to form the follicle are still competent to form dental papilla specific cell types, such as odontoblasts, and produce dentin, if placed in contact with the inner dental epithelium. Cell fate of the dental mesenchyme at this stage is therefore determined by the epithelium.
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Affiliation(s)
- Michaela Rothová
- Department of Craniofacial Development, King's College London, Floor 27 Guy's Tower, Guy's Hospital, London Bridge, SE1 9RT, London, UK.
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Shin JO, Kim EJ, Cho KW, Nakagawa E, Kwon HJ, Cho SW, Jung HS. BMP4 signaling mediates Zeb family in developing mouse tooth. Histochem Cell Biol 2012; 137:791-800. [PMID: 22350174 DOI: 10.1007/s00418-012-0930-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/01/2012] [Indexed: 11/27/2022]
Abstract
Tooth morphogenesis is regulated by sequential and reciprocal interaction between oral epithelium and neural-crest-derived ectomesenchyme. The interaction is controlled by various signal molecules such as bone morphogenetic protein (BMP), Hedgehog, fibroblast growth factor (FGF), and Wnt. Zeb family is known as a transcription factor, which is essential for neural development and neural-crest-derived tissues, whereas the role of the Zeb family in tooth development remains unclear. Therefore, this study aimed to investigate the expression profiles of Zeb1 and Zeb2 during craniofacial development focusing on mesenchyme of palate, hair follicle, and tooth germ from E12.5 to E16.5. In addition, we examined the interaction between Zeb family and BMP4 during tooth development. Both Zeb1 and Zeb2 were expressed at mesenchyme of the palate, hair follicle, and tooth germ throughout the stages. In the case of tooth germ at the cap stage, the expression of Zeb1 and Zeb2 was lost in epithelium-separated dental mesenchyme. However, the expression of Zeb1 and Zeb2 in the dental mesenchyme was recovered by Bmp4 signaling via BMP4-soaked bead and tissue recombination. Our results suggest that Zeb1 and Zeb2, which were mediated by BMP4, play an important role in neural-crest-derived craniofacial organ morphogenesis, such as tooth development.
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Affiliation(s)
- Jeong-Oh Shin
- Division in Anatomy and Developmental Biology, Department of Oral Biology, Research Center for Orofacial Hard Tissue Regeneration, Brain Korea 21 Project, Oral Science Research Center, College of Dentistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, Korea
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Nikdin H, Olsson ML, Hultenby K, Sugars RV. Osteoadherin accumulates in the predentin towards the mineralization front in the developing tooth. PLoS One 2012; 7:e31525. [PMID: 22355375 PMCID: PMC3280325 DOI: 10.1371/journal.pone.0031525] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 01/09/2012] [Indexed: 11/18/2022] Open
Abstract
Background Proteoglycans (PG) are known to be involved in the organization and assembly of the extracellular matrix (ECM) prior to mineral deposition. Osteoadherin (OSAD), a keratan sulphate PG is a member of the small leucine-rich (SLRP) family of PGs and unlike other SLRPs, OSAD expression is restricted to mineralized tissues. It is proposed to have a high affinity for hydroxyapatite and has been shown to be expressed by mature osteoblasts but its exact role remains to be elucidated. Methodology/Principal Findings We investigated the protein distribution of OSAD in the developing mouse tooth using immunohistochemistry and compared its expression with other SLRPs, biglycan (BGN), decorin (DCN) and fibromodulin (FMD). OSAD was found to be specifically localized in the predentin layer of the tooth and focused at the mineralization front. These studies were confirmed at the ultrastructural level using electron microscopy (iEM), where the distribution of immunogold labeled OSAD particles were quantified and significant amounts were found in the predentin, forming a gradient towards the mineralization front. In addition, iEM results revealed OSAD to lie in close association with collagen fibers, further suggesting an important role for OSAD in the organization of the ECM. The expression profile of mineralization-related SLRP genes by rat dental pulp cells exposed to mineralization inducing factors, showed an increase in all SLRP genes. Indeed, OSAD expression was significantly increased during the mineralization process, specifically following, matrix maturation, and finally mineral deposition. Alizarin Red S staining for calcium deposition showed clear bone-like nodules, which support matrix maturation and mineralization. Conclusions These studies provide new evidence for the role of OSAD in the mineralization process and its specific localization in the predentin layer accumulating at the mineralization front highlighting its role in tooth development.
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Affiliation(s)
- Hero Nikdin
- Oral Biology, Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Marie-Louise Olsson
- Oral Biology, Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Kjell Hultenby
- Department of Laboratory Medicine, Clinical Research Centre, Karolinska Institutet, Huddinge University Hospital, Stockholm, Sweden
| | - Rachael V. Sugars
- Oral Biology, Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden
- * E-mail:
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Abstract
Immunohistochemistry is a classic technique used for the localization of antigenic target molecules in -tissue. The method exploits the principle that the target antigen is recognized by specific antibody and is visualized using different detection systems. The subject of this chapter is simultaneous immunohistochemical detection of protein antigens and proliferation marker BrdU in the developing tooth.
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Affiliation(s)
- Sergiy Kyryachenko
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, OR, USA
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Ida-Yonemochi H, Satokata I, Ohshima H, Sato T, Yokoyama M, Yamada Y, Saku T. Morphogenetic roles of perlecan in the tooth enamel organ: an analysis of overexpression using transgenic mice. Matrix Biol 2011; 30:379-88. [PMID: 21933708 DOI: 10.1016/j.matbio.2011.08.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Revised: 07/29/2011] [Accepted: 08/31/2011] [Indexed: 11/18/2022]
Abstract
Perlecan, a heparan sulfate proteoglycan, is enriched in the intercellular space of the enamel organ. To understand the role of perlecan in tooth morphogenesis, we used a keratin 5 promoter to generate transgenic (Tg) mice that over-express perlecan in epithelial cells, and examined their tooth germs at tissue and cellular levels. Immunohistochemistry showed that perlecan was more strongly expressed in the enamel organ cells of Tg mice than in wild-type mice. Histopathology showed wider intercellular spaces in the stellate reticulum of the Tg molars and loss of cellular polarity in the enamel organ, especially in its cervical region. Hertwig's epithelial root sheath (HERS) cells in Tg mice were irregularly aligned due to excessive deposits of perlecan along the inner, as well as on the outer sides of the HERS. Tg molars had dull-ended crowns and outward-curved tooth roots and their enamel was poorly crystallized, resulting in pronounced attrition of molar cusp areas. In Tg mice, expression of integrin β1 mRNA was remarkably higher at E18, while expression of bFGF, TGF-β1, DSPP and Shh was more elevated at P1. The overexpression of perlecan in the enamel organ resulted in irregular morphology of teeth, suggesting that the expression of perlecan regulates growth factor signaling in a stage-dependent manner during each step of the interaction between ameloblast-lineage cells and mesenchymal cells.
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Affiliation(s)
- Hiroko Ida-Yonemochi
- Division of Oral Pathology, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Sciences, 2-5274 Gakkocho-dori, Chuo-ku, Niigata 951-8514, Japan
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42
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Venugopalan SR, Li X, Amen MA, Florez S, Gutierrez D, Cao H, Wang J, Amendt BA. Hierarchical interactions of homeodomain and forkhead transcription factors in regulating odontogenic gene expression. J Biol Chem 2011; 286:21372-83. [PMID: 21504905 PMCID: PMC3122197 DOI: 10.1074/jbc.m111.252031] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Indexed: 11/06/2022] Open
Abstract
FoxJ1 is a forkhead transcription factor expressed in multiple tissues during development and a major regulator of cilia development. FoxJ1(-/-) mice present with defects in odontogenesis, and we correlate these defects to hierarchical interactions between homeodomain factors Pitx2 and Dlx2 with FoxJ1 in regulating their expression through direct physical interactions. Chromatin immunoprecipitation assays reveal endogenous Pitx2 and Dlx2 binding to the Dlx2 promoter and Dlx2 binding to the FoxJ1 promoter as well as Dlx2 and FoxJ1 binding to the amelogenin promoter. PITX2 activation of the Dlx2 promoter is attenuated by a direct Dlx2 physical interaction with PITX2. Dlx2 autoregulates its promoter, and Dlx2 transcriptionally activates the downstream gene FoxJ1. Dlx2 and FoxJ1 physically interact and synergistically regulate both Dlx2 and FoxJ1 promoters. Dlx2 and FoxJ1 also activate the amelogenin promoter, and amelogenin is required for enamel formation and late stage tooth development. FoxJ1(-/-) mice maxillary and mandibular incisors are reduced in length and width and have reduced amelogenin expression. FoxJ1(-/-) mice show a reduced and defective ameloblast layer, revealing a biological effect of these transcription factor hierarchies during tooth morphogenesis. These transcriptional mechanisms may contribute to other developmental processes such as neuronal, pituitary, and heart development.
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Affiliation(s)
- Shankar R. Venugopalan
- From the Texas A&M University Health Science Center, Institute of Biosciences and Technology, Houston, Texas 77030
| | - Xiao Li
- From the Texas A&M University Health Science Center, Institute of Biosciences and Technology, Houston, Texas 77030
| | - Melanie A. Amen
- From the Texas A&M University Health Science Center, Institute of Biosciences and Technology, Houston, Texas 77030
| | - Sergio Florez
- From the Texas A&M University Health Science Center, Institute of Biosciences and Technology, Houston, Texas 77030
| | - Diana Gutierrez
- From the Texas A&M University Health Science Center, Institute of Biosciences and Technology, Houston, Texas 77030
| | - Huojun Cao
- From the Texas A&M University Health Science Center, Institute of Biosciences and Technology, Houston, Texas 77030
| | - Jianbo Wang
- From the Texas A&M University Health Science Center, Institute of Biosciences and Technology, Houston, Texas 77030
| | - Brad A. Amendt
- From the Texas A&M University Health Science Center, Institute of Biosciences and Technology, Houston, Texas 77030
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43
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Bolotovskii AA, Levin BA. [Influence of development pace on pharyngeal teeth formula in Abramis brama (L.) bream: experimental data]. Ontogenez 2011; 42:172-177. [PMID: 21786649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
An experiment on acceleration and retardation of ontogenesis with thyroid manipulation has revealed direct changes in definitive dentition of pharyngeal bones in Abramis brama bream. As development pace accelerates, the number of teeth reduces to the formula 5-4. When development pace slows down, this number increases to the formula 6-5. Moreover, an additional minor row of teeth (1.6-5.1, 2.6-5.2) is formed. The observed changes transcend typical changes happening in nature. It is assumed that heterochronies provoke changes in the number of teeth.
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44
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Radlansky RJ. 10th TMD: Tooth Morphogenesis and Development Meeting, Berlin, 2010. Bull Group Int Rech Sci Stomatol Odontol 2011; 49:1-3. [PMID: 22750363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Accepted: 04/06/2011] [Indexed: 06/01/2023]
Affiliation(s)
- Ralph J Radlansky
- Charité -Campus Benjamin Franklin at Freie Universität Berlin, Center for Dental and Craniofacial Sciences, Dept. of Craniofacial Developmental Biology, Assmannshauser Str. 4-6, 14197 Berlin, Germany. .
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Ida-Yonemochi H, Nakatomi M, Harada H, Ohshima H. O5-differential expression and functional significance of glucose transporters during murine tooth development. Bull Group Int Rech Sci Stomatol Odontol 2011; 49:86. [PMID: 22750369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Accepted: 04/06/2011] [Indexed: 06/01/2023]
Affiliation(s)
- Hiroko Ida-Yonemochi
- Division of Anatomy and Cell Biology of Hard Tissue, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Sciences, 2-5274 Gakkocho-dori, Chuoku, Niigata, Japan
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Cao H, Florez S, Amen M, Huynh T, Skobe Z, Baldini A, Amendt BA. Tbx1 regulates progenitor cell proliferation in the dental epithelium by modulating Pitx2 activation of p21. Dev Biol 2010; 347:289-300. [PMID: 20816801 PMCID: PMC3334818 DOI: 10.1016/j.ydbio.2010.08.031] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2010] [Revised: 08/23/2010] [Accepted: 08/25/2010] [Indexed: 11/19/2022]
Abstract
Tbx1(-/-) mice present with phenotypic effects observed in DiGeorge syndrome patients however, the molecular mechanisms of Tbx1 regulating craniofacial and tooth development are unclear. Analyses of the Tbx1 null mice reveal incisor microdontia, small cervical loops and BrdU labeling reveals a defect in epithelial cell proliferation. Furthermore, Tbx1 null mice molars are lacking normal cusp morphology. Interestingly, p21 (associated with cell cycle arrest) is up regulated in the dental epithelium of Tbx1(-/-) embryos. These data suggest that Tbx1 inhibits p21 expression to allow for cell proliferation in the dental epithelial cervical loop, however Tbx1 does not directly regulate p21 expression. A new molecular mechanism has been identified where Tbx1 inhibits Pitx2 transcriptional activity and decreases the expression of Pitx2 target genes, p21, Lef-1 and Pitx2c. p21 protein is increased in PITX2C transgenic mouse embryo fibroblasts (MEF) and chromatin immunoprecipitation assays demonstrate endogenous Pitx2 binding to the p21 promoter. Tbx1 attenuates PITX2 activation of endogenous p21 expression and Tbx1 null MEFs reveal increased Pitx2a and activation of Pitx2c isoform expression. Tbx1 physically interacts with the PITX2 C-terminus and represses PITX2 transcriptional activation of the p21, LEF-1, and Pitx2c promoters. Tbx1(-/+)/Pitx2(-/+) double heterozygous mice present with an extra premolar-like tooth revealing a genetic interaction between these factors. The ability of Tbx1 to repress PITX2 activation of p21 may promote cell proliferation. In addition, PITX2 regulation of p21 reveals a new role for PITX2 in repressing cell proliferation. These data demonstrate new functional mechanisms for Tbx1 in tooth morphogenesis and provide a molecular basis for craniofacial defects in DiGeorge syndrome patients.
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Affiliation(s)
- Huojun Cao
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX
| | - Sergio Florez
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX
| | - Melanie Amen
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX
| | - Tuong Huynh
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX
| | - Ziedonis Skobe
- Department of Biomineralization, The Forsyth Institute, Boston, MA
| | - Antonio Baldini
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX
- Institute of Genetics and Biophysics CNR, Naples, Italy
| | - Brad A. Amendt
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX
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Paiva KBS, Silva-Valenzuela MDG, Massironi SMG, Ko GM, Siqueira FM, Nunes FD. Differential Shh, Bmp and Wnt gene expressions during craniofacial development in mice. Acta Histochem 2010; 112:508-17. [PMID: 19608221 DOI: 10.1016/j.acthis.2009.05.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Revised: 05/05/2009] [Accepted: 05/19/2009] [Indexed: 01/22/2023]
Abstract
In this study, Bmp-4, Wnt-5a and Shh gene expressions were compared during early craniofacial development in mice by comparative non-isotopic in situ hybridization. Wild-type C57BL/6J mice were studied at various stages of embryonic development (from 8.5- to 13.5-day-old embryos--E8.5-13.5). During early odontogenesis, transcripts for Bmp-4, Shh and Wnt-5a were co-localised at the tooth initiation stage. At E8.5, Shh mRNA expression was restricted to diencephalon and pharyngeal endoderm. Before maxillae and mandible ossification, Bmp-4 and Wnt-5a signals were detected in the mesenchymal cells and around Meckel's cartilage. During palatogenesis, Shh was expressed only in the epithelium and Wnt-5a only in the mesenchyme of the elevating palatal shelves. During tongue development, Shh expression was found in mesenchyme, probably contributing to tongue miogenesis, while Wnt-5a signal was in the epithelium, possibly during placode development and papillae formation. Taken together, these findings suggest that Bmp-4, Shh and Wnt-5a gene expressions may act together on the epithelial-mesenchymal interactions occurring in several aspects of the early mouse craniofacial development, such as odontogenesis, neuronal development, maxillae and mandible ossification, palatogenesis and tongue formation.
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Abstract
During amelogenesis, extracellular matrix proteins interact with growing hydroxyapatite crystals to create one of the most architecturally complex biological tissues. The process of enamel formation is a unique biomineralizing system characterized first by an increase in crystallite length during the secretory phase of amelogenesis, followed by a vast increase in crystallite width and thickness in the later maturation phase when organic complexes are enzymatically removed. Crystal growth is modulated by changes in the pH of the enamel microenvironment that is critical for proper enamel biomineralization. Whereas the genetic bases for most abnormal enamel phenotypes (amelogenesis imperfecta) are generally associated with mutations to enamel matrix specific genes, mutations to genes involved in pH regulation may result in severely affected enamel structure, highlighting the importance of pH regulation for normal enamel development. This review summarizes the intra- and extracellular mechanisms employed by the enamel-forming cells, ameloblasts, to maintain pH homeostasis and, also, discusses the enamel phenotypes associated with disruptions to genes involved in pH regulation.
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Affiliation(s)
- Rodrigo S. Lacruz
- School of Dentistry, Center for Craniofacial Molecular Biology, University of Southern California, 2250 Alcazar Street, CSA Room 103, Los Angeles, CA 90033 USA
| | - Antonio Nanci
- Faculty of Dentistry, Université de Montréal, P.O. Box 6128, Station Centre-Ville, Montreal, QC H3C 3J7 Canada
| | - Ira Kurtz
- David Geffen School Medicine at the University of California at Los Angeles, Los Angeles, 10833 Le Conte Ave., Los Angeles, CA 90095 USA
| | - J. Timothy Wright
- Department of Pediatric Dentistry, School of Dentistry, University of North Carolina at Chapel Hill, CB No. 7450 Brauer Hall, Chapel Hill, NC 27599 USA
| | - Michael L. Paine
- School of Dentistry, Center for Craniofacial Molecular Biology, University of Southern California, 2250 Alcazar Street, CSA Room 103, Los Angeles, CA 90033 USA
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49
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Powers J, Zhao Y, Lin S, McCabe ERB. The expression of nr0b1, the earliest gene in zebrafish tooth development, is a marker for human tooth and ameloblastoma formation. Dev Genes Evol 2009; 219:419-25. [PMID: 19826837 PMCID: PMC2773114 DOI: 10.1007/s00427-009-0300-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Accepted: 08/12/2009] [Indexed: 11/26/2022]
Abstract
Zebrafish teeth develop on pharyngeal jaws in the 5th branchial arch, but early tooth development is remarkably similar to mammals (Borday-Birraux et al., Evol Dev 8:130, 2006). Recently, eve1 has been shown to be associated with the primary tooth (4V1) and early ameloblast development, the enamel organ precursor (Laurenti et al., Dev Dyn 230:727, 2004). dax1 is initially expressed in the 5th branchial arch in zebrafish at approximately 26 h postfertilization (hpf) and colocalizes with eve1 expression at ~48 hpf. Embryos injected with dax1 morpholino show downregulation of eve1 expression. Based on the zebrafish observations, we demonstrated novel DAX1 expression in normal human dental, benign ameloblastoma, and malignant ameloblastoma tissues. The association of NR0B1 and its protein product DAX1 with primary tooth development and ameloblastoma tumorigenesis is an association not previously described.
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Affiliation(s)
- Jamie Powers
- Department of Pediatrics, David Geffen School of Medicine, UCLA, 10833 Le Conte Ave., MDCC B2-375, Los Angeles, 90095 CA USA
- Mattel Children’s Hospital, UCLA, Los Angeles, 90095 CA USA
| | - Yan Zhao
- Molecular, Cell and Developmental Biology, UCLA, P.O. Box 951606, 4325 Life Science Bldg, Los Angeles, 90095-1606 CA USA
| | - Shuo Lin
- Molecular, Cell and Developmental Biology, UCLA, P.O. Box 951606, 4325 Life Science Bldg, Los Angeles, 90095-1606 CA USA
| | - Edward R. B. McCabe
- Mattel Children’s Hospital, UCLA, Los Angeles, 90095 CA USA
- Department of Human Genetics, David Geffen School of Medicine, UCLA, Los Angeles, CA USA
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Science, UCLA, Los Angeles, CA USA
- Department of Pediatrics, David Geffen School of Medicine, UCLA, P.O. Box 951752, 22-412 MDCC, Los Angeles, 90095-1752 CA USA
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Denaxa M, Sharpe PT, Pachnis V. The LIM homeodomain transcription factors Lhx6 and Lhx7 are key regulators of mammalian dentition. Dev Biol 2009; 333:324-36. [PMID: 19591819 PMCID: PMC2738952 DOI: 10.1016/j.ydbio.2009.07.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 07/01/2009] [Accepted: 07/01/2009] [Indexed: 12/30/2022]
Abstract
Genes encoding LIM homeodomain transcription factors are implicated in cell type specification and differentiation during embryogenesis. Two closely related members of this family, Lhx6 and Lhx7, are expressed in the ectomesenchyme of the maxillary and mandibular processes and have been suggested to control patterning of the first branchial arch (BA1) and odontogenesis. However, mice homozygous for single mutations either have no cranial defects (Lhx6) or show only cleft palate (Lhx7). To reveal the potential redundant activities of Lhx6 and Lhx7 in cranial morphogenesis, we generated mice with all combinations of wild-type and mutant alleles. Double homozygous mice have characteristic defects of the cranial skeleton and die shortly after birth, most likely because of cleft palate. In addition, Lhx6/7 deficient embryos lack molar teeth. The absence of molars in double mutants is not due to patterning defects of BA1 but results from failure of specification of the molar mesenchyme. Despite molar agenesis, Lhx6/7-deficient animals have normal incisors which, in the maxilla, are flanked by a supernumerary pair of incisor-like teeth. Our experiments demonstrate that the redundant activities of the LIM homeodomain proteins Lhx6 and Lhx7 are critical for craniofacial development and patterning of mammalian dentition.
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Affiliation(s)
- Myrto Denaxa
- Division of Molecular Neurobiology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK.
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