1
|
Kegulian NC, Visakan G, Bapat RA, Moradian-Oldak J. Ameloblastin and its multifunctionality in amelogenesis: A review. Matrix Biol 2024; 131:62-76. [PMID: 38815936 DOI: 10.1016/j.matbio.2024.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Revised: 05/16/2024] [Accepted: 05/24/2024] [Indexed: 06/01/2024]
Abstract
Extracellular matrix proteins play crucial roles in the formation of mineralized tissues like bone and teeth via multifunctional mechanisms. In tooth enamel, ameloblastin (Ambn) is one such multifunctional extracellular matrix protein implicated in cell signaling and polarity, cell adhesion to the developing enamel matrix, and stabilization of prismatic enamel morphology. To provide a perspective for Ambn structure and function, we begin this review by describing dental enamel and enamel formation (amelogenesis) followed by a description of enamel extracellular matrix. We then summarize the established domains and motifs in Ambn protein, human amelogenesis imperfecta cases, and genetically engineered mouse models involving mutated or null Ambn. We subsequently delineate in silico, in vitro, and in vivo evidence for the amphipathic helix in Ambn as a proposed cell-matrix adhesive and then more recent in vitro evidence for the multitargeting domain as the basis for dynamic interactions of Ambn with itself, amelogenin, and membranes. The multitargeting domain facilitates tuning between Ambn-membrane interactions and self/co-assembly and supports a likely overall role for Ambn as a matricellular protein. We anticipate that this review will enhance the understanding of multifunctional matrix proteins by consolidating diverse mechanisms through which Ambn contributes to enamel extracellular matrix mineralization.
Collapse
Affiliation(s)
- Natalie C Kegulian
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, 2250 Alcazar St., CSA 148, Los Angeles, CA 90033, USA
| | - Gayathri Visakan
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, 2250 Alcazar St., CSA 148, Los Angeles, CA 90033, USA
| | - Rucha Arun Bapat
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, 2250 Alcazar St., CSA 148, Los Angeles, CA 90033, USA
| | - Janet Moradian-Oldak
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, 2250 Alcazar St., CSA 148, Los Angeles, CA 90033, USA.
| |
Collapse
|
2
|
Chiba Y, Yoshizaki K, Sato H, Ikeuchi T, Rhodes C, Chiba M, Saito K, Nakamura T, Iwamoto T, Yamada A, Yamada Y, Fukumoto S. Deficiency of G protein-coupled receptor Gpr111/Adgrf2 causes enamel hypomineralization in mice by alteration of the expression of kallikrein-related peptidase 4 (Klk4) during pH cycling process. FASEB J 2023; 37:e22861. [PMID: 36929047 DOI: 10.1096/fj.202202053r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 03/18/2023]
Abstract
Enamel is formed by the repetitive secretion of a tooth-specific extracellular matrix and its decomposition. Calcification of the enamel matrix via hydroxyapatite (HAP) maturation requires pH cycling to be tightly regulated through the neutralization of protons released during HAP synthesis. We found that Gpr115, which responds to changes in extracellular pH, plays an important role in enamel formation. Gpr115-deficient mice show partial enamel hypomineralization, suggesting that other pH-responsive molecules may be involved. In this study, we focused on the role of Gpr111/Adgrf2, a duplicate gene of Gpr115, in tooth development. Gpr111 was highly expressed in mature ameloblasts. Gpr111-KO mice showed enamel hypomineralization. Dysplasia of enamel rods and high carbon content seen in Gpr111-deficient mice suggested the presence of residual enamel matrices in enamel. Depletion of Gpr111 in dental epithelial cells induced the expression of ameloblast-specific protease, kallikrein-related peptidase 4 (Klk4), suggesting that Gpr111 may act as a suppressor of Klk4 expression. Moreover, reduction of extracellular pH to 6.8 suppressed the expression of Gpr111, while the converse increased Klk4 expression. Such induction of Klk4 was synergistically enhanced by Gpr111 knockdown, suggesting that proper enamel mineralization may be linked to the modulation of Klk4 expression by Gpr111. Furthermore, our in vitro suppression of Gpr111 and Gpr115 expression indicated that their suppressive effect on calcification was additive. These results suggest that both Gpr111 and Gpr115 respond to extracellular pH, contribute to the expression of proteolytic enzymes, and regulate the pH cycle, thereby playing important roles in enamel formation.
Collapse
Affiliation(s)
- Yuta Chiba
- Section of Pediatric Dentistry, Division of Oral Health, Growth and Development, Kyushu University Faculty of Dental Science, Fukuoka, Japan
- Division of Pediatric Dentistry, Department of Community Social Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Keigo Yoshizaki
- Section of Orthodontics and Dentofacial Orthopedics, Division of Oral Health, Growth, and Development, Kyushu University Faculty of Dental Science, Fukuoka, Japan
| | - Hiroshi Sato
- Section of Pediatric Dentistry, Division of Oral Health, Growth and Development, Kyushu University Faculty of Dental Science, Fukuoka, Japan
| | - Tomoko Ikeuchi
- Division of Pediatric Dentistry, Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, USA
| | - Craig Rhodes
- Division of Pediatric Dentistry, Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, USA
| | - Mitsuki Chiba
- Division of Pediatric Dentistry, Department of Community Social Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Kan Saito
- Division of Pediatric Dentistry, Department of Community Social Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Takashi Nakamura
- Division of Molecular Pharmacology and Cell Biophysics, Department of Disease Management Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Tsutomu Iwamoto
- Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Department of Pediatric Dentistry/Special Needs Dentistry, Tokyo Medical and Dental University, Tokyo, Japan
| | - Aya Yamada
- Division of Pediatric Dentistry, Department of Community Social Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Yoshihiko Yamada
- Section of Orthodontics and Dentofacial Orthopedics, Division of Oral Health, Growth, and Development, Kyushu University Faculty of Dental Science, Fukuoka, Japan
| | - Satoshi Fukumoto
- Section of Pediatric Dentistry, Division of Oral Health, Growth and Development, Kyushu University Faculty of Dental Science, Fukuoka, Japan
- Division of Pediatric Dentistry, Department of Community Social Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan
| |
Collapse
|
3
|
Enamel Phenotypes: Genetic and Environmental Determinants. Genes (Basel) 2023; 14:genes14030545. [PMID: 36980818 PMCID: PMC10048525 DOI: 10.3390/genes14030545] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 02/14/2023] [Accepted: 02/16/2023] [Indexed: 02/24/2023] Open
Abstract
Dental enamel is a specialized tissue that has adapted over millions of years of evolution to enhance the survival of a variety of species. In humans, enamel evolved to form the exterior protective layer for the crown of the exposed tooth crown. Its unique composition, structure, physical properties and attachment to the underlying dentin tissue allow it to be a resilient, although not self-repairing, tissue. The process of enamel formation, known as amelogenesis, involves epithelial-derived cells called ameloblasts that secrete a unique extracellular matrix that influences the structure of the mineralizing enamel crystallites. There are over 115 known genetic conditions affecting amelogenesis that are associated with enamel phenotypes characterized by either a reduction of enamel amount and or mineralization. Amelogenesis involves many processes that are sensitive to perturbation and can be altered by numerous environmental stressors. Genetics, epigenetics, and environment factors can influence enamel formation and play a role in resistance/risk for developmental defects and the complex disease, dental caries. Understanding why and how enamel is affected and the enamel phenotypes seen clinically support diagnostics, prognosis prediction, and the selection of treatment approaches that are appropriate for the specific tissue defects (e.g., deficient amount, decreased mineral, reduced insulation and hypersensitivity). The current level of knowledge regarding the heritable enamel defects is sufficient to develop a new classification system and consensus nosology that effectively communicate the mode of inheritance, molecular defect/pathway, and the functional aberration and resulting enamel phenotype.
Collapse
|
4
|
Kegulian NC, Langen R, Moradian-Oldak J. The Dynamic Interactions of a Multitargeting Domain in Ameloblastin Protein with Amelogenin and Membrane. Int J Mol Sci 2023; 24:3484. [PMID: 36834897 PMCID: PMC9966149 DOI: 10.3390/ijms24043484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/28/2023] [Accepted: 02/06/2023] [Indexed: 02/12/2023] Open
Abstract
The enamel matrix protein Ameloblastin (Ambn) has critical physiological functions, including regulation of mineral formation, cell differentiation, and cell-matrix adhesion. We investigated localized structural changes in Ambn during its interactions with its targets. We performed biophysical assays and used liposomes as a cell membrane model. The xAB2N and AB2 peptides were rationally designed to encompass regions of Ambn that contained self-assembly and helix-containing membrane-binding motifs. Electron paramagnetic resonance (EPR) on spin-labeled peptides showed localized structural gains in the presence of liposomes, amelogenin (Amel), and Ambn. Vesicle clearance and leakage assays indicated that peptide-membrane interactions were independent from peptide self-association. Tryptophan fluorescence and EPR showed competition between Ambn-Amel and Ambn-membrane interactions. We demonstrate localized structural changes in Ambn upon interaction with different targets via a multitargeting domain, spanning residues 57 to 90 of mouse Ambn. Structural changes of Ambn following its interaction with different targets have relevant implications for the multifunctionality of Ambn in enamel formation.
Collapse
Affiliation(s)
- Natalie C. Kegulian
- Center for Craniofacial Molecular Biology, Department of Biomedical Sciences, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, USA
| | - Ralf Langen
- Department of Neuroscience and Physiology, Department of Biochemistry and Molecular Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Janet Moradian-Oldak
- Center for Craniofacial Molecular Biology, Department of Biomedical Sciences, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, USA
| |
Collapse
|
5
|
Visakan G, Bapat RA, Su J, Moradian-Oldak J. Modeling ameloblast-matrix interactions using 3D cell culture. Front Physiol 2022; 13:1069519. [PMID: 36531170 PMCID: PMC9751369 DOI: 10.3389/fphys.2022.1069519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 11/21/2022] [Indexed: 12/02/2022] Open
Abstract
The distinct morphology adopted by ameloblasts during amelogenesis is highly stage specific and involved intimately with the development of a hierarchical enamel microstructure. The molecular mechanisms that govern the development of an elongated and polarized secretory ameloblast morphology and the potential roles played by the enamel matrix proteins in this process are not fully understood. Thus far, the in vitro models that have been developed to mimic these early cell-matrix interactions have either been unable to demonstrate direct morphological change or have failed to adapt across ameloblast cell lines. Here, we use a recently established 3D cell culture model to examine the interactions between HAT-7 cells and the major enamel matrix proteins, amelogenin and ameloblastin. We demonstrate that HAT-7 cells selectively respond to functional EMPs in culture by forming clusters of tall cells. Aspect ratio measurements from three-dimensional reconstructions reveal that cell elongation is 5-times greater in the presence of EMPs when compared with controls. Using confocal laser scanning microscopy, we observe that these clusters are polarized with asymmetrical distributions of Par-3 and claudin-1 proteins. The behavior of HAT-7 cells in 3D culture with EMPs is comparable with that of ALC and LS-8 cells. The fact that the 3D model presented here is tunable with respect to gel substrate composition and ameloblast cell type highlights the overall usefulness of this model in studying ameloblast cell morphology in vitro.
Collapse
|
6
|
Buchko GW, Mergelsberg ST, Tarasevich BJ, Shaw WJ. Residue-Specific Insights into the Intermolecular Protein–Protein Interfaces Driving Amelogenin Self-Assembly in Solution. Biochemistry 2022; 61:2909-2921. [DOI: 10.1021/acs.biochem.2c00522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Affiliation(s)
- Garry W. Buchko
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
- School of Molecular Biosciences, Washington State University, Pullman, Washington 99164, United States
| | - Sebastian T. Mergelsberg
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Barbara J. Tarasevich
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Wendy J. Shaw
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| |
Collapse
|
7
|
Visakan G, Su J, Moradian-Oldak J. Ameloblastin promotes polarization of ameloblast cell lines in a 3-D cell culture system. Matrix Biol 2022; 105:72-86. [PMID: 34813898 PMCID: PMC8955733 DOI: 10.1016/j.matbio.2021.11.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/12/2021] [Accepted: 11/16/2021] [Indexed: 01/03/2023]
Abstract
Studies on animal models with mutations in ameloblastin gene have suggested that the extracellular matrix protein ameloblastin (AMBN) plays important roles in controlling cell-matrix adhesion and ameloblast polarization during amelogenesis. In order to examine the function of AMBN in cell polarization and morphology, we developed an in vitro 3D cell culture model to examine the effect of AMBN and amelogenin (AMEL) addition on ameloblast cell lines. We further used high resolution confocal microscopy to detect expression of polarization markers in response to AMBN addition. Addition of AMBN to the 3D culture matrix resulted in the clustering and elongation (higher aspect ratio) of ALC in a dose dependent manner. The molar concentration of AMEL required to exact this response from ALC was 2.75- times greater than that of AMBN. This polarization effect of ameloblastin was attributable directly to an evolutionary conserved domain within its exon 5-encoded region. The lack of exon 6-encoded region also influenced AMBN-cell interactions but to a lesser extent. The clusters formed with AMBN were polarized with expression of E-cadherin, Par3 and Cldn1 assembly at the nascent cell-cell junctions. The elongation effect was specific to epithelial cells of ameloblastic lineage ALC and LS8 cells. Our data suggest that AMBN may play critical signaling roles in the initiation of cell polarity by acting as a communicator between cell-cell and cell-matrix interactions. Our investigation has important implications for understanding the function of ameloblastin in enamel-cell matrix adhesion and the outcomes may contribute to efforts to develop strategies for enamel tissue regeneration.
Collapse
|
8
|
Huang Y, Bai Y, Chang C, Bacino M, Cheng IC, Li L, Habelitz S, Li W, Zhang Y. A N-Terminus Domain Determines Amelogenin's Stability to Guide the Development of Mouse Enamel Matrix. J Bone Miner Res 2021; 36:1781-1795. [PMID: 33957008 PMCID: PMC9307086 DOI: 10.1002/jbmr.4329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 04/25/2021] [Accepted: 04/29/2021] [Indexed: 12/16/2022]
Abstract
Amelogenins, the principal proteins in the developing enamel microenvironment, self-assemble into supramolecular structures to govern the remodeling of a proteinaceous organic matrix into longitudinally ordered hydroxyapatite nanocrystal arrays. Extensive in vitro studies using purified native or recombinant proteins have revealed the potential of N-terminal amelogenin on protein self-assembly and its ability to guide the mineral deposition. We have previously identified a 14-aa domain (P2) of N-terminal amelogenin that can self-assemble into amyloid-like fibrils in vitro. Here, we investigated how this domain affects the ability of amelogenin self-assembling and stability of enamel matrix protein scaffolding in an in vivo animal model. Mice harboring mutant amelogenin lacking P2 domain had a hypoplastic, hypomineralized, and aprismatic enamel. In vitro, the mutant recombinant amelogenin without P2 had a reduced tendency to self-assemble and was prone to accelerated hydrolysis by MMP20, the prevailing metalloproteinase in early developing enamel matrix. A reduced amount of amelogenins and a lack of elongated fibrous assemblies in the development enamel matrix of mutant mice were evident compared with that in the wild-type mouse enamel matrix. Our study is the first to demonstrate that a subdomain (P2) at the N-terminus of amelogenin controls amelogenin's assembly into a transient protein scaffold that resists rapid proteolysis during enamel development in an animal model. Understanding the building blocks of fibrous scaffold that guides the longitudinal growth of hydroxyapatites in enamel matrix sheds light on protein-mediated enamel bioengineering. © 2021 American Society for Bone and Mineral Research (ASBMR).
Collapse
Affiliation(s)
- Yulei Huang
- Department of Orofacial Sciences, University of California, San Francisco, CA, USA.,Preventive and Restorative Dental Sciences, University of California, San Francisco, CA, USA
| | - Yushi Bai
- Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Sun-Yat-sen University, Guangzhou, China
| | - Chih Chang
- Department of Orofacial Sciences, University of California, San Francisco, CA, USA
| | - Margot Bacino
- Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Sun-Yat-sen University, Guangzhou, China
| | - Ieong Cheng Cheng
- Department of Orofacial Sciences, University of California, San Francisco, CA, USA
| | - Li Li
- Department of Orofacial Sciences, University of California, San Francisco, CA, USA
| | - Stefan Habelitz
- Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Sun-Yat-sen University, Guangzhou, China
| | - Wu Li
- Department of Orofacial Sciences, University of California, San Francisco, CA, USA
| | - Yan Zhang
- Department of Orofacial Sciences, University of California, San Francisco, CA, USA
| |
Collapse
|
9
|
Wang J, Liu Z, Ren B, Wang Q, Wu J, Yang N, Sui X, Li L, Li M, Zhang X, Li X, Wang B. Biomimetic mineralisation systems for in situ enamel restoration inspired by amelogenesis. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2021; 32:115. [PMID: 34455518 PMCID: PMC8403113 DOI: 10.1007/s10856-021-06583-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 07/05/2021] [Indexed: 05/28/2023]
Abstract
Caries and dental erosion are common oral diseases. Traditional treatments involve the mechanical removal of decay and filling but these methods are not suitable for cases involving large-scale enamel erosion, such as hypoplasia. To develop a noninvasive treatment, promoting remineralisation in the early stage of caries is of considerable clinical significance. Therefore, biomimetic mineralisation is an ideal approach for restoring enamel. Biomimetic mineralisation forms a new mineral layer that is tightly attached to the surface of the enamel. This review details the state-of-art achievements on the application of amelogenin and non-amelogenin, amorphous calcium phosphate, ions flow and other techniques in the biomimetic mineralisation of enamel. The ultimate goal of this review was to shed light on the requirements for enamel biomineralisation. Hence, herein, we summarise two strategies of biological minimisation systems for in situ enamel restoration inspired by amelogenesis that have been developed in recent years and compare their advantages and disadvantages.
Collapse
Affiliation(s)
- Jue Wang
- Department of Obsterics and Gynecology, The Second Hospital of Jilin University, Changchun, Jilin, China
- Department of Prosthodontics, Hospital of Stomatology, Jilin University, Changchun, Jilin, China
| | - Zhihui Liu
- Department of Prosthodontics, Hospital of Stomatology, Jilin University, Changchun, Jilin, China
| | - Bingyu Ren
- Department of Thyroid surgery, The Second Hospital of Jilin University, Changchun, Jilin, China
| | - Qian Wang
- Department of Prosthodontics, Hospital of Stomatology, Jilin University, Changchun, Jilin, China
| | - Jia Wu
- Department of Prosthodontics, Hospital of Stomatology, Jilin University, Changchun, Jilin, China
| | - Nan Yang
- Department of Prosthodontics, Hospital of Stomatology, Jilin University, Changchun, Jilin, China
| | - Xin Sui
- Department of Prosthodontics, Hospital of Stomatology, Jilin University, Changchun, Jilin, China
| | - Lingfeng Li
- Department of Prosthodontics, Hospital of Stomatology, Jilin University, Changchun, Jilin, China
| | - Meihui Li
- Department of Prosthodontics, Hospital of Stomatology, Jilin University, Changchun, Jilin, China
| | - Xiao Zhang
- Department of Prosthodontics, Hospital of Stomatology, Jilin University, Changchun, Jilin, China
| | - Xinyue Li
- Department of Prosthodontics, Hospital of Stomatology, Jilin University, Changchun, Jilin, China
| | - Bowei Wang
- Department of Obsterics and Gynecology, The Second Hospital of Jilin University, Changchun, Jilin, China.
| |
Collapse
|
10
|
Ji Y, Li C, Tian Y, Gao Y, Dong Z, Xiang L, Xu Z, Gao Y, Zhang L. Maturation stage enamel defects in Odontogenesis-associated phosphoprotein (Odaph) deficient mice. Dev Dyn 2021; 250:1505-1517. [PMID: 33772937 DOI: 10.1002/dvdy.336] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 02/28/2021] [Accepted: 03/22/2021] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Mutation in Odontogenesis-associated phosphoprotein (ODAPH) has been reported to cause recessive hypomineralized amelogenesis imperfecta (AI) in human. However, the exact role of ODAPH in amelogenesis is still unknown. RESULTS ODAPH was identified as a novel constituent of the atypical basal lamina located at the interface between maturation ameloblasts and the enamel by dual immunofluorescence staining of ODAPH and LAMC2. Odaph knockout mice were generated to explore the function of ODAPH in amelogenesis. Odaph-/- mice teeth showed severely attrition and reduced enamel mineralization. Histological analysis showed from transition or early-maturation stage, ameloblasts were rapidly shortened, lost cell polarity, and exhibited cell pathology. Abundant enamel matrix marked by amelogenin was retained. Temporary cyst-like structures were formed between flattened epithelial cells and the enamel from maturation stage to eruption. The integrity of the atypical basal lamina was impaired indicated by the reduced diffuse expression of LAMC2 and AMTN. The expression of maturation stage related genes of Amtn, Klk4, Integrinβ6 and Slc24a4 were significantly decreased. CONCLUSIONS Our results suggested Odaph played vital roles during amelogenesis by maintaining the integrity of the atypical basal lamina in maturation stage, which may contribute to a better understanding of the pathophysiology of human AI.
Collapse
Affiliation(s)
- Yikang Ji
- Department of Stomatology, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, Shandong, China
| | - Cong Li
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, Shandong, China
| | - Yuan Tian
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, Shandong, China
| | - Yan Gao
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, Shandong, China
| | - Zhiheng Dong
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, Shandong, China
| | - Lili Xiang
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, Shandong, China
| | - Zhenzhen Xu
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, Shandong, China
| | - Yuguang Gao
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, Shandong, China.,Institute of Stomatology, Binzhou Medical University, Yantai, Shandong, China
| | - Li Zhang
- Department of Stomatology, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, Shandong, China.,Institute of Stomatology, Binzhou Medical University, Yantai, Shandong, China
| |
Collapse
|
11
|
Sharma V, Srinivasan A, Nikolajeff F, Kumar S. Biomineralization process in hard tissues: The interaction complexity within protein and inorganic counterparts. Acta Biomater 2021; 120:20-37. [PMID: 32413577 DOI: 10.1016/j.actbio.2020.04.049] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 04/17/2020] [Accepted: 04/26/2020] [Indexed: 02/07/2023]
Abstract
Biomineralization can be considered as nature's strategy to produce and sustain biominerals, primarily via creation of hard tissues for protection and support. This review examines the biomineralization process within the hard tissues of the human body with special emphasis on the mechanisms and principles of bone and teeth mineralization. We describe the detailed role of proteins and inorganic ions in mediating the mineralization process. Furthermore, we highlight the various available models for studying bone physiology and mineralization starting from the historical static cell line-based methods to the most advanced 3D culture systems, elucidating the pros and cons of each one of these methods. With respect to the mineralization process in teeth, enamel and dentin mineralization is discussed in detail. The key role of intrinsically disordered proteins in modulating the process of mineralization in enamel and dentine is given attention. Finally, nanotechnological interventions in the area of bone and teeth mineralization, diseases and tissue regeneration is also discussed. STATEMENT OF SIGNIFICANCE: This article provides an overview of the biomineralization process within hard tissues of the human body, which encompasses the detailed mechanism innvolved in the formation of structures like teeth and bone. Moreover, we have discussed various available models used for studying biomineralization and also explored the nanotechnological applications in the field of bone regeneration and dentistry.
Collapse
Affiliation(s)
- Vaibhav Sharma
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.
| | | | | | - Saroj Kumar
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.
| |
Collapse
|
12
|
Wang X, Chiba Y, Jia L, Yoshizaki K, Saito K, Yamada A, Qin M, Fukumoto S. Expression Patterns of Claudin Family Members During Tooth Development and the Role of Claudin-10 ( Cldn10) in Cytodifferentiation of Stratum Intermedium. Front Cell Dev Biol 2020; 8:595593. [PMID: 33195274 PMCID: PMC7642450 DOI: 10.3389/fcell.2020.595593] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 10/07/2020] [Indexed: 02/05/2023] Open
Abstract
There is growing evidence showing that tight junctions play an important role in developing enamel. Claudins are one of the main components of tight junctions and may have pivotal functions in modulating various cellular events, such as regulating cell differentiation and proliferation. Mutations in CLDN10 of humans are associated with HELIX syndrome and cause enamel defects. However, current knowledge regarding the expression patterns of claudins and the function of Cldn10 during tooth development remains fragmented. In this study, we aimed to analyze the expression patterns of claudin family members during tooth development and to investigate the role of Cldn10 in amelogenesis. Using cap analysis gene expression of developing mouse tooth germs compared with that of the whole body, we found that Cldn1 and Cldn10 were highly expressed in the tooth. Furthermore, single-cell RNA-sequence analysis using 7-day postnatal Krt14-RFP mouse incisors revealed Cldn1 and Cldn10 exhibited distinct expression patterns. Cldn10 has two isoforms, Cldn10a and Cldn10b, but only Cldn10b was expressed in the tooth. Immunostaining of developing tooth germs revealed claudin-10 was highly expressed in the inner enamel epithelium and stratum intermedium. We also found that overexpression of Cldn10 in the dental epithelial cell line, SF2, induced alkaline phosphatase (Alpl) expression, a marker of maturated stratum intermedium. Our findings suggest that Cldn10 may be a novel stratum intermedium marker and might play a role in cytodifferentiation of stratum intermedium.
Collapse
Affiliation(s)
- Xin Wang
- Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology, Beijing, China.,Division of Pediatric Dentistry, Department of Oral Health and Development Sciences, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Yuta Chiba
- Division of Pediatric Dentistry, Department of Oral Health and Development Sciences, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Lingling Jia
- Division of Pediatric Dentistry, Department of Oral Health and Development Sciences, Tohoku University Graduate School of Dentistry, Sendai, Japan.,State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Keigo Yoshizaki
- Section of Orthodontics and Dentofacial Orthopedics, Division of Oral Health, Growth and Development, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| | - Kan Saito
- Division of Pediatric Dentistry, Department of Oral Health and Development Sciences, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Aya Yamada
- Division of Pediatric Dentistry, Department of Oral Health and Development Sciences, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Man Qin
- Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology, Beijing, China
| | - Satoshi Fukumoto
- Division of Pediatric Dentistry, Department of Oral Health and Development Sciences, Tohoku University Graduate School of Dentistry, Sendai, Japan.,Section of Oral Medicine for Children, Division of Oral Health, Growth and Development, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| |
Collapse
|
13
|
Wang SK, Zhang H, Chavez MB, Hu Y, Seymen F, Koruyucu M, Kasimoglu Y, Colvin CD, Kolli TN, Tan MH, Wang YL, Lu PY, Kim JW, Foster BL, Bartlett JD, Simmer JP, Hu JCC. Dental malformations associated with biallelic MMP20 mutations. Mol Genet Genomic Med 2020; 8:e1307. [PMID: 32495503 PMCID: PMC7434610 DOI: 10.1002/mgg3.1307] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/07/2020] [Accepted: 04/08/2020] [Indexed: 12/30/2022] Open
Abstract
Background Matrix metallopeptidase 20 (MMP20) is an evolutionarily conserved protease that is essential for processing enamel matrix proteins during dental enamel formation. MMP20 mutations cause human autosomal recessive pigmented hypomaturation‐type amelogenesis imperfecta (AI2A2; OMIM #612529). MMP20 is expressed in both odontoblasts and ameloblasts, but its function during dentinogenesis is unclear. Methods We characterized 10 AI kindreds with MMP20 defects, characterized human third molars and/or Mmp20−/− mice by histology, Backscattered Scanning Electron Microscopy (bSEM), µCT, and nanohardness testing. Results We identified six novel MMP20 disease‐causing mutations. Four pathogenic variants were associated with exons encoding the MMP20 hemopexin‐like (PEX) domain, suggesting a necessary regulatory function. Mutant human enamel hardness was softest (13% of normal) midway between the dentinoenamel junction (DEJ) and the enamel surface. bSEM and µCT analyses of the third molars revealed reduced mineral density in both enamel and dentin. Dentin close to the DEJ showed an average hardness number 62%–69% of control. Characterization of Mmp20−/− mouse dentin revealed a significant reduction in dentin thickness and mineral density and a transient increase in predentin thickness, indicating disturbances in dentin matrix secretion and mineralization. Conclusion These results expand the spectrum of MMP20 disease‐causing mutations and provide the first evidence for MMP20 function during dentin formation.
Collapse
Affiliation(s)
- Shih-Kai Wang
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI, USA.,Department of Pediatric Dentistry, National Taiwan University School of Dentistry, Taipei City, Taiwan R.O.C
| | - Hong Zhang
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| | - Michael B Chavez
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - Yuanyuan Hu
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| | - Figen Seymen
- Department of Pedodontics, Istanbul University Faculty of Dentistry, Istanbul, Turkey
| | - Mine Koruyucu
- Department of Pedodontics, Istanbul University Faculty of Dentistry, Istanbul, Turkey
| | - Yelda Kasimoglu
- Department of Pedodontics, Istanbul University Faculty of Dentistry, Istanbul, Turkey
| | - Connor D Colvin
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - Tamara N Kolli
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - Michelle H Tan
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - Yin-Lin Wang
- Department of Pediatric Dentistry, National Taiwan University School of Dentistry, Taipei City, Taiwan R.O.C
| | - Pei-Ying Lu
- Department of Pediatric Dentistry, National Taiwan University School of Dentistry, Taipei City, Taiwan R.O.C
| | - Jung-Wook Kim
- Department of Pediatric Dentistry & Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Republic of Korea.,Department of Molecular Genetics & Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Republic of Korea
| | - Brian L Foster
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - John D Bartlett
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - James P Simmer
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| | - Jan C-C Hu
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| |
Collapse
|
14
|
Shin NY, Yamazaki H, Beniash E, Yang X, Margolis SS, Pugach MK, Simmer JP, Margolis HC. Amelogenin phosphorylation regulates tooth enamel formation by stabilizing a transient amorphous mineral precursor. J Biol Chem 2020; 295:1943-1959. [PMID: 31919099 DOI: 10.1074/jbc.ra119.010506] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 12/30/2019] [Indexed: 11/06/2022] Open
Abstract
Dental enamel comprises interwoven arrays of extremely long and narrow crystals of carbonated hydroxyapatite called enamel rods. Amelogenin (AMELX) is the predominant extracellular enamel matrix protein and plays an essential role in enamel formation (amelogenesis). Previously, we have demonstrated that full-length AMELX forms higher-order supramolecular assemblies that regulate ordered mineralization in vitro, as observed in enamel rods. Phosphorylation of the sole AMELX phosphorylation site (Ser-16) in vitro greatly enhances its capacity to stabilize amorphous calcium phosphate (ACP), the first mineral phase formed in developing enamel, and prevents apatitic crystal formation. To test our hypothesis that AMELX phosphorylation is critical for amelogenesis, we generated and characterized a hemizygous knockin (KI) mouse model with a phosphorylation-defective Ser-16 to Ala-16 substitution in AMELX. Using EM analysis, we demonstrate that in the absence of phosphorylated AMELX, KI enamel lacks enamel rods, the hallmark component of mammalian enamel, and, unlike WT enamel, appears to be composed of less organized arrays of shorter crystals oriented normal to the dentinoenamel junction. KI enamel also exhibited hypoplasia and numerous surface defects, whereas heterozygous enamel displayed highly variable mosaic structures with both KI and WT features. Importantly, ACP-to-apatitic crystal transformation occurred significantly faster in KI enamel. Secretory KI ameloblasts also lacked Tomes' processes, consistent with the absence of enamel rods, and underwent progressive cell pathology throughout enamel development. In conclusion, AMELX phosphorylation plays critical mechanistic roles in regulating ACP-phase transformation and enamel crystal growth, and in maintaining ameloblast integrity and function during amelogenesis.
Collapse
Affiliation(s)
- Nah-Young Shin
- The Forsyth Institute, Cambridge, Massachusetts 02142; Department of Developmental Biology, Harvard School of Dental Medicine, Boston, Massachusetts 02115
| | - Hajime Yamazaki
- The Forsyth Institute, Cambridge, Massachusetts 02142; Department of Developmental Biology, Harvard School of Dental Medicine, Boston, Massachusetts 02115; Department of Oral Biology, Center for Craniofacial Regeneration, University of Pittsburgh, School of Dental Medicine, Pittsburgh, Pennsylvania 15213
| | - Elia Beniash
- Department of Oral Biology, Center for Craniofacial Regeneration, University of Pittsburgh, School of Dental Medicine, Pittsburgh, Pennsylvania 15213
| | - Xu Yang
- Department of Oral Biology, Center for Craniofacial Regeneration, University of Pittsburgh, School of Dental Medicine, Pittsburgh, Pennsylvania 15213
| | - Seth S Margolis
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Megan K Pugach
- The Forsyth Institute, Cambridge, Massachusetts 02142; Department of Developmental Biology, Harvard School of Dental Medicine, Boston, Massachusetts 02115
| | - James P Simmer
- Department of Biologic and Material Sciences, University of Michigan School of Dentistry, Ann Arbor, Michigan 48108
| | - Henry C Margolis
- The Forsyth Institute, Cambridge, Massachusetts 02142; Department of Developmental Biology, Harvard School of Dental Medicine, Boston, Massachusetts 02115; Department of Periodontics and Preventive Dentistry, Center for Craniofacial Regeneration, University of Pittsburgh, School of Dental Medicine, Pittsburgh, Pennsylvania 15213.
| |
Collapse
|
15
|
Sukseree S, Schwarze UY, Gruber R, Gruber F, Quiles Del Rey M, Mancias JD, Bartlett JD, Tschachler E, Eckhart L. ATG7 is essential for secretion of iron from ameloblasts and normal growth of murine incisors during aging. Autophagy 2020; 16:1851-1857. [PMID: 31880208 DOI: 10.1080/15548627.2019.1709764] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The incisors of rodents comprise an iron-rich enamel and grow throughout adult life, making them unique models of iron metabolism and tissue homeostasis during aging. Here, we deleted Atg7 (autophagy related 7) in murine ameloblasts, i.e. the epithelial cells that produce enamel. The absence of ATG7 blocked the transport of iron from ameloblasts into the maturing enamel, leading to a white instead of yellow surface of maxillary incisors. In aging mice, lack of ATG7 was associated with the growth of ectopic incisors inside severely deformed primordial incisors. These results suggest that 2 characteristic features of rodent incisors, i.e. deposition of iron on the enamel surface and stable growth during aging, depend on autophagic activity in ameloblasts. Abbreviations: ATG5: autophagy related 5; ATG7: autophagy related 7; CMV: cytomegalovirus; Cre: Cre recombinase; CT: computed tomography; FTH1: ferritin heavy polypeptide 1; GFP: green fluorescent protein; KRT5: keratin 5; KRT14: keratin 14; LGALS3: lectin, galactose binding, soluble 3; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; NCOA4: nuclear receptor coactivator 4; NRF2: nuclear factor, erythroid 2 like 2; SQSTM1: sequestosome 1.
Collapse
Affiliation(s)
- Supawadee Sukseree
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna , Vienna, Austria
| | | | - Reinhard Gruber
- Department of Oral Biology, Medical University of Vienna , Vienna, Austria
| | - Florian Gruber
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna , Vienna, Austria
| | - Maria Quiles Del Rey
- Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Dana-Farber Cancer Institute , Boston, MA, USA
| | - Joseph D Mancias
- Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Dana-Farber Cancer Institute , Boston, MA, USA
| | - John D Bartlett
- Division of Biosciences, College of Dentistry, The Ohio State University , Columbus, OH, USA
| | - Erwin Tschachler
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna , Vienna, Austria
| | - Leopold Eckhart
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna , Vienna, Austria
| |
Collapse
|
16
|
Pang L, Li X, Wang K, Tao Y, Cui T, Xu Q, Lin H. Interactions with the aquaporin 5 gene increase the susceptibility to molar-incisor hypomineralization. Arch Oral Biol 2019; 111:104637. [PMID: 31884335 DOI: 10.1016/j.archoralbio.2019.104637] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 12/14/2019] [Accepted: 12/18/2019] [Indexed: 12/31/2022]
Abstract
OBJECTIVE The aim of this study was to evaluate whether individual genetic factors involved in amelogenesis, the immune response and water channel proteins may increase the susceptibility to Molar-Incisor Hypomineralization (MIH) in Chinese children. DESIGN DNA samples were collected from 86 cases with MIH cases and 344 controls. Sixteen single-nucleotide polymorphisms (SNPs) were investigated. Logistic regression analysis was performed to assess association between SNPs and the risk of MIH. RESULTS Our results showed that the risk of MIH in the rs13115627-AA genotype carriers and the rs1784418-TT genotype carriers were significantly higher than that among those with the rs13115627-GG genotype (OR (95 % CI)) = 4.942 (0.658-37.131) and the rs1784418-CT genotype (OR (95 % CI)) = 2.023 (1.63-3.521). The population with the rs1800972-CC genotype and the rs1800972-C allele had a higher risk to develop MIH, OR (95 % CI) = 2.284 (1.267-4.115), OR (95 % CI) = 2.427 (1.493-3.953) respectively. In the Aquaporin 5(AQP5) gene, we individually analyzed two SNPs, rs1996315 and rs923911. We found no significant associations between them and MIH. However, in the analysis of the gene-gene interactions, we discovered a significant two-locus model (P = 0.023) involving rs1996315 and rs923911. Participants with the rs1996315-AG and rs923911-AC genotypes had the highest MIH risk, compared to participants with the rs1996315-GG and rs923911-CC genotypes, OR (95 % CI) = 3.603 (1.147-11.318). CONCLUSION This study showed that genetic variants in the AMBN, MMP20 and DEFB1 genes may contribute to MIH in the permanent dentition of children. Moreover, interactions among AQP5 gene may also increase the MIH susceptibility.
Collapse
Affiliation(s)
- Liangyue Pang
- Department of Preventive Dentistry, Guanghua School of Stomatology, Sun Yat-sen University, 56 Ling Yuan Road West, 510050 Guangzhou, China; Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, 510080, Guangzhou, China
| | - Xia Li
- Foshan Stomatology Hospital, School of Stomatology and Medicine, Foshan University, Foshan, China
| | - Ketian Wang
- Department of Preventive Dentistry, Guanghua School of Stomatology, Sun Yat-sen University, 56 Ling Yuan Road West, 510050 Guangzhou, China; Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, 510080, Guangzhou, China
| | - Ye Tao
- Department of Preventive Dentistry, Guanghua School of Stomatology, Sun Yat-sen University, 56 Ling Yuan Road West, 510050 Guangzhou, China; Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, 510080, Guangzhou, China
| | - Tianqiang Cui
- Foshan Stomatology Hospital, School of Stomatology and Medicine, Foshan University, Foshan, China
| | - Qiong Xu
- Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, 510080, Guangzhou, China.
| | - Huancai Lin
- Department of Preventive Dentistry, Guanghua School of Stomatology, Sun Yat-sen University, 56 Ling Yuan Road West, 510050 Guangzhou, China; Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, 510080, Guangzhou, China.
| |
Collapse
|
17
|
Zhang Y, Zheng L, Le M, Nakano Y, Chan B, Huang Y, Torbaty PM, Kohwi Y, Marcucio R, Habelitz S, Den Besten PK, Kohwi-Shigematsu T. SATB1 establishes ameloblast cell polarity and regulates directional amelogenin secretion for enamel formation. BMC Biol 2019; 17:104. [PMID: 31830989 PMCID: PMC6909472 DOI: 10.1186/s12915-019-0722-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 11/13/2019] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Polarity is necessary for epithelial cells to perform distinct functions at their apical and basal surfaces. Oral epithelial cell-derived ameloblasts at secretory stage (SABs) synthesize large amounts of enamel matrix proteins (EMPs), largely amelogenins. EMPs are unidirectionally secreted into the enamel space through their apical cytoplasmic protrusions, or Tomes' processes (TPs), to guide the enamel formation. Little is known about the transcriptional regulation underlying the establishment of cell polarity and unidirectional secretion of SABs. RESULTS The higher-order chromatin architecture of eukaryotic genome plays important roles in cell- and stage-specific transcriptional programming. A genome organizer, special AT-rich sequence-binding protein 1 (SATB1), was discovered to be significantly upregulated in ameloblasts compared to oral epithelial cells using a whole-transcript microarray analysis. The Satb1-/- mice possessed deformed ameloblasts and a thin layer of hypomineralized and non-prismatic enamel. Remarkably, Satb1-/- ameloblasts at the secretory stage lost many morphological characteristics found at the apical surface of wild-type (wt) SABs, including the loss of Tomes' processes, defective inter-ameloblastic adhesion, and filamentous actin architecture. As expected, the secretory function of Satb1-/- SABs was compromised as amelogenins were largely retained in cells. We found the expression of epidermal growth factor receptor pathway substrate 8 (Eps8), a known regulator for actin filament assembly and small intestinal epithelial cytoplasmic protrusion formation, to be SATB1 dependent. In contrast to wt SABs, EPS8 could not be detected at the apical surface of Satb1-/- SABs. Eps8 expression was greatly reduced in small intestinal epithelial cells in Satb1-/- mice as well, displaying defective intestinal microvilli. CONCLUSIONS Our data show that SATB1 is essential for establishing secretory ameloblast cell polarity and for EMP secretion. In line with the deformed apical architecture, amelogenin transport to the apical secretory front and secretion into enamel space were impeded in Satb1-/- SABs resulting in a massive cytoplasmic accumulation of amelogenins and a thin layer of hypomineralized enamel. Our studies strongly suggest that SATB1-dependent Eps8 expression plays a critical role in cytoplasmic protrusion formation in both SABs and in small intestines. This study demonstrates the role of SATB1 in the regulation of amelogenesis and the potential application of SATB1 in ameloblast/enamel regeneration.
Collapse
Affiliation(s)
- Yan Zhang
- Department of Orofacial Sciences, University of California, San Francisco, USA.
| | - Liwei Zheng
- Department of Orofacial Sciences, University of California, San Francisco, USA
| | - Michael Le
- Department of Orofacial Sciences, University of California, San Francisco, USA
| | - Yukiko Nakano
- Department of Orofacial Sciences, University of California, San Francisco, USA
| | - Barry Chan
- Department of Orofacial Sciences, University of California, San Francisco, USA
| | - Yulei Huang
- Department of Orofacial Sciences, University of California, San Francisco, USA
| | | | - Yoshinori Kohwi
- Department of Orofacial Sciences, University of California, San Francisco, USA
| | - Ralph Marcucio
- Department of Orthopaedic Surgery, University of California, San Francisco, USA
| | - Stefan Habelitz
- Preventive and Restorative Dental Sciences, University of California, San Francisco, USA
| | - Pamela K Den Besten
- Department of Orofacial Sciences, University of California, San Francisco, USA
| | | |
Collapse
|
18
|
Matrix metalloproteinases and inhibitors in dentistry. Clin Oral Investig 2019; 23:2823-2835. [PMID: 31093743 DOI: 10.1007/s00784-019-02915-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 04/24/2019] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Matrix metalloproteinase (MMP) expression has been associated with tissue development, invasive cancer cell behavior, and inflammation. The associations of increased expression of MMPs with diseases have led to intensive research activities to develop MMP inhibitors. Here, the questions are addressed which associations between increased levels of any MMP with dental diseases may be cause or consequence, whether MMP levels may be of diagnostic value and whether and which MMP inhibitors need further investigations for use in dental diseases. METHODS To study the role of MMPs and to discriminate between cause or consequence, the literature about measurements of MMPs and about the use of inhibitory drugs and genetic knockout animal models in dentistry was compared. RESULTS The only FDA-approved treatment with MMP inhibitors is tetracyclines for periodontitis, whereas a diagnostic test for activated MMP-8 in oral fluids is valued in practical periodontology. The MMP literature in dentistry is artificially skewed to the gelatinases MMP-2 and MMP-9 and to enamelysin, alias MMP-20. The basis for this observation is, respectively, the widely used and sensitive technique of gelatin zymography and enamel proteins as substrates of MMP-20. Studies on additional MMPs are gaining interest in dentistry and MMP inhibitors may provide new applications. In addition, drugs with proven effects for the treatment of dental diseases may be found to act through MMP inhibition. CONCLUSION AND RELEVANCE In conclusion, research on MMPs and inhibitors may provide practical applications beyond diagnosis and treatment of periodontitis and will be, directly or indirectly, beneficial for patients with dental or periodontal diseases.
Collapse
|
19
|
Aseervatham J, Geetu S, Anunobi CC, Koli K, Ogbureke KUE. Survey of dentin sialophosphoprotein and its cognate matrix metalloproteinase-20 in human cancers. Cancer Med 2019; 8:2167-2178. [PMID: 30932369 PMCID: PMC6537041 DOI: 10.1002/cam4.2117] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 03/10/2019] [Indexed: 01/05/2023] Open
Abstract
Background Matrix metalloproteinases‐20 (MMP20) expression is widely regarded as tooth specific, with expression limited to dental hard tissues. Recently, we reported MMP20 expression and interaction with dentin sialophosphoprotein (DSPP), a member of the Small Integrin Binding Ligand N‐linked Glycoproteins (SIBLINGs), in human oral squamous cell carcinoma (OSCC) and dysplastic oral premalignant lesions (OPLs), suggesting a role for MMP20‐DSPP interaction in oral carcinogenesis. Methods This study aimed to survey the expression of MMP20 and its cognate DSPP partner in the breast, colon, prostate, thyroid, and cervical neoplasms. Using commercially available tissue microarrays (TMAs) and cell lines, we performed immunohistochemistry, immunofluorescence, proximity ligation assay, and western blot experiments to determine the expressions of MMP20 and DSPP in the breast, colon, prostate, thyroid, cervical neoplasms, and their normal counterparts. Results Significantly high expression levels of MMP20 and DSPP were observed in the malignant breast, colon, prostate, thyroid, and cervical neoplasms compared with their benign and normal counterparts. Furthermore, MMP20 levels increased with advanced stages of colon and thyroid cancers. DSPP expression increased significantly with tumor stage in all cancers examined. Conclusions The co‐localization and potential MMP20‐DSPP interaction previously reported in oral cancers are present in other cancers. These results suggest MMP20‐DSPP pairing as a potential marker of disease activity in some epithelial cancers with diagnostic and prognostic implications.
Collapse
Affiliation(s)
- Jaya Aseervatham
- Department of Diagnostic and Biomedical Sciences, University of Texas School of Dentistry at Houston, Houston, Texas
| | - Saxena Geetu
- Department of Diagnostic and Biomedical Sciences, University of Texas School of Dentistry at Houston, Houston, Texas
| | - Charles C Anunobi
- Department of Anatomic and Molecular Pathology, College of Medicine, University of Lagos, Lagos, Nigeria
| | - Komal Koli
- Department of Diagnostic and Biomedical Sciences, University of Texas School of Dentistry at Houston, Houston, Texas
| | - Kalu U E Ogbureke
- Department of Diagnostic and Biomedical Sciences, University of Texas School of Dentistry at Houston, Houston, Texas
| |
Collapse
|
20
|
Yamazaki H, Tran B, Beniash E, Kwak SY, Margolis HC. Proteolysis by MMP20 Prevents Aberrant Mineralization in Secretory Enamel. J Dent Res 2019; 98:468-475. [PMID: 30744480 DOI: 10.1177/0022034518823537] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The present study was conducted to investigate the role of proteolysis by matrix metalloproteinase 20 (MMP20) in regulating the initial formation of the enamel mineral structure during the secretory stage of amelogenesis, utilizing Mmp20-null mice that lack this essential protease. Ultrathin sagittal sections of maxillary incisors from 8-wk-old wild-type (WT), Mmp20-null (KO), and heterozygous (HET) littermates were prepared. Secretory-stage enamel ultrastructures from each genotype as a function of development were compared using transmission electron microscopy, selected area electron diffraction, and Raman microspectroscopy. Characteristic rod structures observed in WT enamel exhibited amorphous features in newly deposited enamel, which subsequently transformed into apatite-like crystals in older enamel. Surprisingly, initial mineral formation in KO enamel was found to proceed in the same manner as in the WT. However, soon after a rod structure began to form, large plate-like crystals appeared randomly within the developing KO enamel layer. As development continued, observed plate-like crystals became dominant and obscured the appearance of the enamel rod structure. Upon formation of these plate-like crystals, the KO enamel layer stopped growing in thickness, unlike WT and HET enamel layers that continued to grow at the same rate. Raman results indicated that Mmp20-KO enamel contains a significant portion of octacalcium phosphate, unlike WT enamel. Although normal in all other respects, large, randomly dispersed mineral crystals were observed in secretory HET enamel, although to a lesser extent than that seen in KO enamel, indicating that the level of MMP20 expression has a proportional effect on suppressing aberrant mineral formation. In conclusion, we found that proteolysis of extracellular enamel matrix proteins by MMP20 is not required for the initial development of the enamel rod structure during the early secretory stage of amelogenesis. Proteolysis by MMP20, however, is essential for the prevention of abnormal crystal formation during amelogenesis.
Collapse
Affiliation(s)
- H Yamazaki
- 1 The Forsyth Institute, Cambridge, MA, USA.,2 Department of Developmental Biology, Harvard School of Dental Medicine, Boston, MA, USA
| | - B Tran
- 3 Simmons College, Boston, MA, USA
| | - E Beniash
- 4 Center for Craniofacial Regeneration, Department of Oral Biology, University of Pittsburgh School of Dental Medicine, Pittsburgh, PA, USA
| | - S Y Kwak
- 1 The Forsyth Institute, Cambridge, MA, USA.,2 Department of Developmental Biology, Harvard School of Dental Medicine, Boston, MA, USA
| | - H C Margolis
- 1 The Forsyth Institute, Cambridge, MA, USA.,2 Department of Developmental Biology, Harvard School of Dental Medicine, Boston, MA, USA
| |
Collapse
|
21
|
Manno SH, Manno FA, Ahmed I, Ahmed R, Shu L, Li L, Xu S, Xie F, Li VW, Ho J, Cheng SH, Lau C. Spectroscopic examination of enamel staining by coffee indicates dentin erosion by sequestration of elements. Talanta 2018; 189:550-559. [DOI: 10.1016/j.talanta.2018.07.032] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 07/06/2018] [Accepted: 07/11/2018] [Indexed: 12/14/2022]
|
22
|
Ji M, Xiao L, Xu L, Huang S, Zhang D. How pH is regulated during amelogenesis in dental fluorosis. Exp Ther Med 2018; 16:3759-3765. [PMID: 30402142 DOI: 10.3892/etm.2018.6728] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 12/01/2017] [Indexed: 12/14/2022] Open
Abstract
Amelogenesis is a complicated process that concerns the interaction between growing hydroxyapatite crystals and extracellular proteins, which requires the tight regulation of pH. In dental fluorosis, the balance of pH regulation is broken, leading to abnormal mineralization. The current review focuses on the electrolyte transport processes associated with pH homeostasis, particularly regarding the changes in ion transporters that occur during amelogenesis, following exposure to excessive fluoride. Furthermore, the possible mechanism of fluorosis is discussed on the basis of acid hypothesis. There are two main methods by which F- accelerates crystal formation in ameloblasts. Firstly, it induces the release of protons, lowering the pH of the cell microenvironment. The decreased pH stimulates the upregulation of ion transporters, which attenuates further declines in the pH. Secondly, F- triggers an unknown signaling pathway, causing changes in the transcription of ion transporters and upregulating the expression of bicarbonate transporters. This results in the release of a large amount of bicarbonate from ameloblasts, which may neutralize the pH to form a microenvironment that favors crystal nucleation. The decreased pH stimulates the diffusion of F- into the cytoplasm of amelobalsts along the concentration gradient formed by the release of protons. The retention of F- causes a series of pathological changes, including oxidative and endoplasmic reticulum stress. If the buffering capacity of ameloblasts facing F- toxicity holds, normal mineralization occurs; however, if F- levels are high enough to overwhelm the buffering capacity of ameloblasts, abnormal mineralization occurs, leading to dental fluorosis.
Collapse
Affiliation(s)
- Mei Ji
- Department of Stomatology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Lili Xiao
- Department of Stomatology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Le Xu
- Department of Stomatology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Shengyun Huang
- Department of Stomatology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| | - Dongsheng Zhang
- Department of Stomatology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China
| |
Collapse
|
23
|
Jiang N, Chen L, Ma Q, Ruan J. Nanostructured Ti surfaces and retinoic acid/dexamethasone present a spatial framework for the maturation and amelogenesis of LS-8 cells. Int J Nanomedicine 2018; 13:3949-3964. [PMID: 30022819 PMCID: PMC6042561 DOI: 10.2147/ijn.s167629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To investigate the amelogenesis-inductive effects of surface structures at the nanoscale. For this purpose, variable nanostructured titanium dioxide (TiO2) surfaces were used as a framework to regulate the amelogenic behaviors of ameloblasts with the administration of retinoic acid (RA)/dexamethasone (DEX). MATERIALS AND METHODS TiO2 nanotubular (NT) surfaces were fabricated via anodization. Mouse ameloblast-like LS-8 cells were seeded and cultured on NT surfaces in the presence or absence of RA/DEX for 48 h. The amelogenic behaviors and extracellular matrix (ECM) mineralization of LS-8 cells on nanostructured Ti surfaces were characterized using field emission scanning electron microscope, laser scanning confocal microscope, quantitative polymerase chain reaction, MTT assay, and flow cytometry. RESULTS TiO2 NT surfaces (tube size ~30 and ~80 nm) were constructed via anodization at 5 or 20 V and denoted as NT5 and NT20, respectively. LS-8 cells exhibited significantly increased spread and proliferation, and lower rates of apoptosis and necrosis on NT surfaces. The amelogenic gene expression and ECM mineralization differed significantly on the NT20 and the NT5 and polished Ti sample surfaces in standard medium. The amelogenic behaviors of LS-8 cells were further changed by RA/DEX pretreatment, which directly drove maturation of LS-8 cells. CONCLUSION Controlling the amelogenic behaviors of ameloblast-like LS-8 cells by manipulating the nanostructure of biomaterials surfaces represents an effective tool for the establishment of a systemic framework for supporting enamel regeneration. The administration of RA/DEX is an effective approach for driving the amelogenesis and maturation of ameloblasts.
Collapse
Affiliation(s)
- Nan Jiang
- Department of Preventive Dentistry, College of Stomatology, Xi'an JiaoTong University, Xi'an, People's Republic of China,
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an JiaoTong University, Xi'an, People's Republic of China,
- Clinical Research Center of Shaanxi Province for Dental and Maxillofacial Diseases, College of Stomatology, Xi'an JiaoTong University, Xi'an, People's Republic of China,
| | - Lu Chen
- Department of Preventive Dentistry, College of Stomatology, Xi'an JiaoTong University, Xi'an, People's Republic of China,
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an JiaoTong University, Xi'an, People's Republic of China,
- Clinical Research Center of Shaanxi Province for Dental and Maxillofacial Diseases, College of Stomatology, Xi'an JiaoTong University, Xi'an, People's Republic of China,
| | - Qianli Ma
- Department of Immunology, School of Basic Medicine, Fourth Military Medical University, Xi'an, People's Republic of China,
- Department of Prosthodontics, College of Stomatology, Xi'an JiaoTong University, Xi'an, People's Republic of China,
| | - Jianping Ruan
- Department of Preventive Dentistry, College of Stomatology, Xi'an JiaoTong University, Xi'an, People's Republic of China,
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an JiaoTong University, Xi'an, People's Republic of China,
- Clinical Research Center of Shaanxi Province for Dental and Maxillofacial Diseases, College of Stomatology, Xi'an JiaoTong University, Xi'an, People's Republic of China,
| |
Collapse
|
24
|
Chu Q, Gao Y, Gao X, Dong Z, Song W, Xu Z, Xiang L, Wang Y, Zhang L, Li M, Gao Y. Ablation of Runx2 in Ameloblasts Suppresses Enamel Maturation in Tooth Development. Sci Rep 2018; 8:9594. [PMID: 29941908 PMCID: PMC6018461 DOI: 10.1038/s41598-018-27873-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 06/11/2018] [Indexed: 11/21/2022] Open
Abstract
Runt-related transcription factor 2 (Runx2) is involved in the early stage of tooth development. However, only few studies have reported the role of Runx2 in enamel development, which may be attributed to that Runx2 full knockout mice cannot survive after birth. In the present study, we successfully established a Runx2-deficient mouse model using a conditional knockout (cKO) method. We observed a significant reduction in the degree of mineralization and the decreased size of enamel rods in cKO mice. Histological analysis showed the retained enamel proteins in enamel layer at maturation stage in cKO molars. Further analysis by qRT-PCR revealed that the expressions of genes encoding enamel structure proteins, such as amelogenin (AMELX), ameloblastin (AMBN) and enamelin (ENAM), were increased in cKO enamel organs. On the other hand, the expression of kallikrein-related peptidase-4 (KLK4) at the mRNA and protein levels was dramatically decreased from late secretory stage to maturation stage in cKO enamel organs, while the expression of matrix metalloproteinase-20 (MMP-20) was not significantly altered. Finally, immunohistochemistry indicated that the uptake of amelogenins by ameloblasts was significantly decreased in cKO mice. Taken together, Runx2 played critical roles in controlling enamel maturation by increasing synthesis of KLK4 and decreasing synthesis of AMELX, AMBN and ENAM.
Collapse
Affiliation(s)
- Qing Chu
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Yan Gao
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Xianhua Gao
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Zhiheng Dong
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Wenying Song
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Zhenzhen Xu
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Lili Xiang
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Yumin Wang
- Institute of Stomatology, Binzhou Medical University, Yantai, 255000, Shandong, China
| | - Li Zhang
- Institute of Stomatology, Binzhou Medical University, Yantai, 255000, Shandong, China
| | - Mingyu Li
- Shanghai Key Laboratory of Stomatology, Shanghai Research Institute of Stomatology, Ninth People's Hospital, Faculty of Medicine, Shanghai Jiao Tong University, Shanghai, 200011, China
| | - Yuguang Gao
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China.
| |
Collapse
|
25
|
Buchko GW, Jayasinha Arachchige R, Tao J, Tarasevich BJ, Shaw WJ. Identification of major matrix metalloproteinase-20 proteolytic processing products of murine amelogenin and tyrosine-rich amelogenin peptide using a nuclear magnetic resonance spectroscopy based method. Arch Oral Biol 2018; 93:187-194. [PMID: 29960917 DOI: 10.1016/j.archoralbio.2018.06.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 05/31/2018] [Accepted: 06/01/2018] [Indexed: 01/14/2023]
Abstract
OBJECTIVE The aim of this study was to identify major matrix metalloproteinase-20 (MMP20) proteolytic processing products of amelogenin over time and determine if the tyrosine-rich amelogenin peptide (TRAP) was a substrate of MMP20. DESIGN Recombinant15N-labeled murine amelogenin and 13C,15N-labeled TRAP were incubated with MMP20 under conditions where amelogenin self-assembles into nanospheres. Digestion products were fractionated by reverse-phase high-performance liquid chromatography at various time points. Product identification took advantage of the intrinsic disorder property of amelogenin that results in little change to its fingerprint 1H-15N heteronuclear single-quantum coherence nuclear magnetic resonance spectrum in 2% acetic acid upon removing parts of the protein, allowing cleavage site identification by observing which amide cross peaks disappear. RESULTS The primary product in five out of the six major reverse-phase high-performance liquid chromatography bands generated after a 24 h incubation of murine amelogenin with MMP20 were: S55-L163, P2-L147, P2-E162, P2-A167, and P2-R176. After 72 h these products were replaced with five major reverse-phase high-performance liquid chromatography bands containing: L46-A170, P2-S152, P2-F151, P2-W45, and short N-terminal peptides. TRAP was completely digested by MMP20 into multiple small peptides with the initial primary site of cleavage between S16 and Y17. CONCLUSIONS Identification of the major MMP20 proteolytic products of amelogenin confirm a dynamic process, with sites towards the C-terminus more rapidly attacked than sites near the N-terminus. This observation is consistent with nanosphere models where the C-terminus is exposed and the N-terminus more protected. One previously reported end-product of the MMP20 proteolytic processing of amelogenin, TRAP, is shown to be an in vitro substrate for MMP20.
Collapse
Affiliation(s)
- Garry W Buchko
- Pacific Northwest National Laboratory, Richland, WA 99352, USA; School of Molecular Biosciences, Washington State University, Pullman, WA 99164, USA.
| | | | - Jinhui Tao
- Pacific Northwest National Laboratory, Richland, WA 99352, USA.
| | | | - Wendy J Shaw
- Pacific Northwest National Laboratory, Richland, WA 99352, USA.
| |
Collapse
|
26
|
Smith EE, Zhang W, Schiele NR, Khademhosseini A, Kuo CK, Yelick PC. Developing a biomimetic tooth bud model. J Tissue Eng Regen Med 2017; 11:3326-3336. [PMID: 28066993 PMCID: PMC6687074 DOI: 10.1002/term.2246] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 04/11/2016] [Accepted: 06/20/2016] [Indexed: 12/31/2022]
Abstract
A long-term goal is to bioengineer, fully functional, living teeth for regenerative medicine and dentistry applications. Biologically based replacement teeth would avoid insufficiencies of the currently used dental implants. Using natural tooth development as a guide, a model was fabricated using post-natal porcine dental epithelial (pDE), porcine dental mesenchymal (pDM) progenitor cells, and human umbilical vein endothelial cells (HUVEC) encapsulated within gelatin methacrylate (GelMA) hydrogels. Previous publications have shown that post-natal DE and DM cells seeded onto synthetic scaffolds exhibited mineralized tooth crowns composed of dentin and enamel. However, these tooth structures were small and formed within the pores of the scaffolds. The present study shows that dental cell-encapsulated GelMA constructs can support mineralized dental tissue formation of predictable size and shape. Individually encapsulated pDE or pDM cell GelMA constructs were analysed to identify formulas that supported pDE and pDM cell attachment, spreading, metabolic activity, and neo-vasculature formation with co-seeded endothelial cells (HUVECs). GelMa constructs consisting of pDE-HUVECS in 3% GelMA and pDM-HUVECs within 5% GelMA supported dental cell differentiation and vascular mineralized dental tissue formation in vivo. These studies are the first to demonstrate the use of GelMA hydrogels to support the formation of post-natal dental progenitor cell-derived mineralized and functionally vascularized tissues of specified size and shape. These results introduce a novel three-dimensional biomimetic tooth bud model for eventual bioengineered tooth replacement teeth in humans. Copyright © 2017 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Elizabeth E. Smith
- Department of Cell, Molecular, and Developmental Biology,
Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine
Boston USA
| | - Weibo Zhang
- Department of Orthodontics Tufts University School of
Dental Medicine Boston MA USA
| | - Nathan R. Schiele
- Department of Biomedical Engineering Tufts University
Science and Technology Center Medford MA USA
| | - Ali Khademhosseini
- Division of Health Sciences and Technology Harvard-MIT
Biomaterials Innovations Research Center and Division of Biomedical Engineering,
Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Catherine K. Kuo
- Center for Musculoskeletal Research Genetics, Department of
Biomedical Engineering, University of Rochester, Rochester, NY, USA
| | - Pamela C. Yelick
- Department of Cell, Molecular, and Developmental Biology,
Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine
Boston USA
- Department of Orthodontics Tufts University School of
Dental Medicine Boston MA USA
- Department of Biomedical Engineering Tufts University
Science and Technology Center Medford MA USA
| |
Collapse
|
27
|
Yan WJ, Ma P, Tian Y, Wang JY, Qin CL, Feng JQ, Wang XF. The importance of a potential phosphorylation site in enamelin on enamel formation. Int J Oral Sci 2017; 9:e4. [PMID: 29593332 PMCID: PMC5775333 DOI: 10.1038/ijos.2017.41] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2017] [Indexed: 01/31/2023] Open
Abstract
Enamelin (ENAM) has three putative phosphoserines (pSers) phosphorylated by a Golgi-associated secretory pathway kinase (FAM20C) based on their distinctive Ser-x-Glu (S-x-E) motifs. Fam20C-knockout mice show severe enamel defects similar to those in the Enam-knockout mice, implying an important role of the pSers in ENAM. To determine the role of pSer55 in ENAM, we characterized ENAMRgsc514 mice, in which Ser55 cannot be phosphorylated by FAM20C due to an E57>G57 mutation in the S-x-E motif. The enamel microstructure of 4-week-old mice was examined by scanning electron microscopy. The teeth of 6-day-old mice were characterized by histology and immunohistochemistry. The protein lysates of the first lower molars of 4-day-old mice were analyzed by Western immunoblotting using antibodies against ENAM, ameloblastin and amelogenin. ENAMRgsc514 heterozygotes showed a disorganized enamel microstructure, while the homozygotes had no enamel on the dentin surface. The N-terminal fragments of ENAM in the heterozygotes were detained in the ameloblasts and localized in the mineralization front of enamel matrix, while those in the WT mice were secreted out of ameloblasts and distributed evenly in the outer 1/2 of enamel matrix. Surprisingly, the ~15 kDa C-terminal fragments of ameloblastin were not detected in the molar lysates of the homozygotes. These results suggest that the phosphorylation of Ser55 may be an essential posttranslational modification of ENAM and is required for the interaction with other enamel matrix molecules such as ameloblastin in mediating the structural organization of enamel matrix and protein-mineral interactions during enamel formation.International Journal of Oral Science (2017) 9;e4; doi:10.1038/ijos.2017.41; published online 29 November 2017.
Collapse
Affiliation(s)
- Wen-Juan Yan
- Department of Biomedical Sciences and Center for Craniofacial Research and Diagnosis, Texas A&M University College of Dentistry, Dallas, USA.,Department of Endodontics, Nanfan Hospital, Southern Medical University, Guangzhou, China
| | - Pan Ma
- Department of Biomedical Sciences and Center for Craniofacial Research and Diagnosis, Texas A&M University College of Dentistry, Dallas, USA
| | - Ye Tian
- Department of Biomedical Sciences and Center for Craniofacial Research and Diagnosis, Texas A&M University College of Dentistry, Dallas, USA
| | - Jing-Ya Wang
- Department of Biomedical Sciences and Center for Craniofacial Research and Diagnosis, Texas A&M University College of Dentistry, Dallas, USA
| | - Chun-Lin Qin
- Department of Biomedical Sciences and Center for Craniofacial Research and Diagnosis, Texas A&M University College of Dentistry, Dallas, USA
| | - Jian Q Feng
- Department of Biomedical Sciences and Center for Craniofacial Research and Diagnosis, Texas A&M University College of Dentistry, Dallas, USA
| | - Xiao-Fang Wang
- Department of Biomedical Sciences and Center for Craniofacial Research and Diagnosis, Texas A&M University College of Dentistry, Dallas, USA
| |
Collapse
|
28
|
Pandya M, Liu H, Dangaria SJ, Zhu W, Li LL, Pan S, Abufarwa M, Davis RG, Guggenheim S, Keiderling T, Luan X, Diekwisch TGH. Integrative Temporo-Spatial, Mineralogic, Spectroscopic, and Proteomic Analysis of Postnatal Enamel Development in Teeth with Limited Growth. Front Physiol 2017; 8:793. [PMID: 29114228 PMCID: PMC5660681 DOI: 10.3389/fphys.2017.00793] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 09/27/2017] [Indexed: 12/11/2022] Open
Abstract
Tooth amelogenesis is a complex process beginning with enamel organ cell differentiation and enamel matrix secretion, transitioning through changes in ameloblast polarity, cytoskeletal, and matrix organization, that affects crucial biomineralization events such as mineral nucleation, enamel crystal growth, and enamel prism organization. Here we have harvested the enamel organ including the pliable enamel matrix of postnatal first mandibular mouse molars during the first 8 days of tooth enamel development to conduct a step-wise cross-sectional analysis of the changes in the mineral and protein phase. Mineral phase diffraction pattern analysis using single-crystal, powder sample X-ray diffraction analysis indicated conversion of calcium phosphate precursors to partially fluoride substituted hydroxyapatite from postnatal day 4 (4 dpn) onwards. Attenuated total reflectance spectra (ATR) revealed a substantial elevation in phosphate and carbonate incorporation as well as structural reconfiguration between postnatal days 6 and 8. Nanoscale liquid chromatography coupled with tandem mass spectrometry (nanoLC-MS/MS) demonstrated highest protein counts for ECM/cell surface proteins, stress/heat shock proteins, and alkaline phosphatase on postnatal day 2, high counts for ameloblast cytoskeletal proteins such as tubulin β5, tropomyosin, β-actin, and vimentin on postnatal day 4, and elevated levels of cofilin-1, calmodulin, and peptidyl-prolyl cis-trans isomerase on day 6. Western blot analysis of hydrophobic enamel proteins illustrated continuously increasing amelogenin levels from 1 dpn until 8 dpn, while enamelin peaked on days 1 and 2 dpn, and ameloblastin on days 1-5 dpn. In summary, these data document the substantial changes in the enamel matrix protein and mineral phase that take place during postnatal mouse molar amelogenesis from a systems biological perspective, including (i) relatively high levels of matrix protein expression during the early secretory stage on postnatal day 2, (ii) conversion of calcium phosphates to apatite, peak protein folding and stress protein counts, and increased cytoskeletal protein levels such as actin and tubulin on day 4, as well as (iii) secondary structure changes, isomerase activity, highest amelogenin levels, and peak phosphate/carbonate incorporation between postnatal days 6 and 8. Together, this study provides a baseline for a comprehensive understanding of the mineralogic and proteomic events that contribute to the complexity of mammalian tooth enamel development.
Collapse
Affiliation(s)
- Mirali Pandya
- Texas A&M Center for Craniofacial Research and Diagnosis, Dallas, TX, United States
| | - Hui Liu
- Brodie Laboratory for Craniofacial Genetics, University of Illinois at Chicago, Chicago, IL, United States
| | - Smit J Dangaria
- Brodie Laboratory for Craniofacial Genetics, University of Illinois at Chicago, Chicago, IL, United States
| | - Weiying Zhu
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL, United States
| | - Leo L Li
- Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Shuang Pan
- Brodie Laboratory for Craniofacial Genetics, University of Illinois at Chicago, Chicago, IL, United States
| | - Moufida Abufarwa
- Texas A&M Center for Craniofacial Research and Diagnosis, Dallas, TX, United States
| | - Roderick G Davis
- Proteomics Center of Excellence, Northwestern University, Evanston, IL, United States
| | - Stephen Guggenheim
- Department of Earth and Environmental Sciences, University of Illinois at Chicago, Chicago, IL, United States
| | | | - Xianghong Luan
- Brodie Laboratory for Craniofacial Genetics, University of Illinois at Chicago, Chicago, IL, United States
| | - Thomas G H Diekwisch
- Texas A&M Center for Craniofacial Research and Diagnosis, Dallas, TX, United States
| |
Collapse
|
29
|
Lacruz RS, Habelitz S, Wright JT, Paine ML. DENTAL ENAMEL FORMATION AND IMPLICATIONS FOR ORAL HEALTH AND DISEASE. Physiol Rev 2017; 97:939-993. [PMID: 28468833 DOI: 10.1152/physrev.00030.2016] [Citation(s) in RCA: 223] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 01/10/2017] [Accepted: 01/10/2017] [Indexed: 12/16/2022] Open
Abstract
Dental enamel is the hardest and most mineralized tissue in extinct and extant vertebrate species and provides maximum durability that allows teeth to function as weapons and/or tools as well as for food processing. Enamel development and mineralization is an intricate process tightly regulated by cells of the enamel organ called ameloblasts. These heavily polarized cells form a monolayer around the developing enamel tissue and move as a single forming front in specified directions as they lay down a proteinaceous matrix that serves as a template for crystal growth. Ameloblasts maintain intercellular connections creating a semi-permeable barrier that at one end (basal/proximal) receives nutrients and ions from blood vessels, and at the opposite end (secretory/apical/distal) forms extracellular crystals within specified pH conditions. In this unique environment, ameloblasts orchestrate crystal growth via multiple cellular activities including modulating the transport of minerals and ions, pH regulation, proteolysis, and endocytosis. In many vertebrates, the bulk of the enamel tissue volume is first formed and subsequently mineralized by these same cells as they retransform their morphology and function. Cell death by apoptosis and regression are the fates of many ameloblasts following enamel maturation, and what cells remain of the enamel organ are shed during tooth eruption, or are incorporated into the tooth's epithelial attachment to the oral gingiva. In this review, we examine key aspects of dental enamel formation, from its developmental genesis to the ever-increasing wealth of data on the mechanisms mediating ionic transport, as well as the clinical outcomes resulting from abnormal ameloblast function.
Collapse
Affiliation(s)
- Rodrigo S Lacruz
- Department of Basic Science and Craniofacial Biology, College of Dentistry, New York University, New York, New York; Department of Preventive and Restorative Dental Sciences, University of California, San Francisco, San Francisco, California; Department of Pediatric Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina; Herman Ostrow School of Dentistry, Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, California
| | - Stefan Habelitz
- Department of Basic Science and Craniofacial Biology, College of Dentistry, New York University, New York, New York; Department of Preventive and Restorative Dental Sciences, University of California, San Francisco, San Francisco, California; Department of Pediatric Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina; Herman Ostrow School of Dentistry, Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, California
| | - J Timothy Wright
- Department of Basic Science and Craniofacial Biology, College of Dentistry, New York University, New York, New York; Department of Preventive and Restorative Dental Sciences, University of California, San Francisco, San Francisco, California; Department of Pediatric Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina; Herman Ostrow School of Dentistry, Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, California
| | - Michael L Paine
- Department of Basic Science and Craniofacial Biology, College of Dentistry, New York University, New York, New York; Department of Preventive and Restorative Dental Sciences, University of California, San Francisco, San Francisco, California; Department of Pediatric Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina; Herman Ostrow School of Dentistry, Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, California
| |
Collapse
|
30
|
Prajapati S, Ruan Q, Mukherjee K, Nutt S, Moradian-Oldak J. The Presence of MMP-20 Reinforces Biomimetic Enamel Regrowth. J Dent Res 2017; 97:84-90. [PMID: 28846464 DOI: 10.1177/0022034517728504] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Biomimetic synthesis of artificial enamel is a promising strategy for the prevention and restoration of defective enamel. We have recently reported that a hydrogel system composed of chitosan-amelogenin (CS-AMEL) and calcium phosphate is effective in forming an enamel-like layer that has a seamless interface with natural tooth surfaces. Here, to improve the mechanical system function and to facilitate the biomimetic enamel regrowth, matrix metalloproteinase-20 (MMP-20) was introduced into the CS-AMEL hydrogel. Inspired by our recent finding that MMP-20 prevents protein occlusion inside enamel crystals, we hypothesized that addition of MMP-20 to CS-AMEL hydrogel could reinforce the newly grown layer. Recombinant human MMP-20 was added to the CS-AMEL hydrogel to cleave full-length amelogenin during the growth of enamel-like crystals on an etched enamel surface. The MMP-20 proteolysis of amelogenin was studied, and the morphology, composition, and mechanical properties of the newly grown layer were characterized. We found that amelogenin was gradually degraded by MMP-20 in the presence of chitosan. The newly grown crystals in the sample treated with MMP-20-CS-AMEL hydrogel showed more uniform orientation and greater crystallinity than the samples treated with CS-AMEL hydrogel without MMP-20. Stepwise processing of amelogenin by MMP-20 in the CS-AMEL hydrogel prevented undesirable protein occlusion within the newly formed crystals. As a result, both the modulus and hardness of the repaired enamel were significantly increased (1.8- and 2.4-fold, respectively) by the MMP-20-CS-AMEL hydrogel. Although future work is needed to further incorporate other enamel matrix proteins into the system, this study brings us one step closer to biomimetic enamel regrowth.
Collapse
Affiliation(s)
- S Prajapati
- 1 Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
| | - Q Ruan
- 1 Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
| | - K Mukherjee
- 1 Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
| | - S Nutt
- 2 Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA, USA
| | - J Moradian-Oldak
- 1 Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
| |
Collapse
|
31
|
Mansour A, Mezour MA, Badran Z, Tamimi F. * Extracellular Matrices for Bone Regeneration: A Literature Review. Tissue Eng Part A 2017; 23:1436-1451. [PMID: 28562183 DOI: 10.1089/ten.tea.2017.0026] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The gold standard material for bone regeneration is still autologous bone, a mesenchymal tissue that consists mainly of extracellular matrix (ECM) (90% v/v) and little cellular content (10% v/v). However, the fact that decellularized allogenic bone grafts often present a clinical performance comparable to autologous bone grafts demonstrates the crucial role of ECM in bone regeneration. For long, the mechanism by which bone allografts function was not clear, but recent research has unveiled many unique characteristics of ECM that seem to play a key role in tissue regeneration. This is further confirmed by the fact that synthetic biomaterials with composition and properties resembling bone ECM present excellent bone regeneration properties. In this context, ECM molecules such as glycosaminoglycans (GAGs) and self-assembly peptides (SAPs) can improve the performance of bone regeneration biomaterials. Moreover, decellularized ECM derived either from native tissues such as bone, cartilage, skin, and tooth germs or from cells such as osteoblasts, chondrocytes, and stem cells has shown promising results in bone regeneration applications. Understanding the role of ECM in bone regeneration is crucial for the development of the next generation of biomaterials for bone tissue engineering. In this sense, this review addresses the state-of-the-art on this subject matter.
Collapse
Affiliation(s)
- Alaa Mansour
- 1 Faculty of Dentistry, McGill University , Montreal, Canada
| | | | - Zahi Badran
- 1 Faculty of Dentistry, McGill University , Montreal, Canada .,2 Department of Periodontology (CHU/UIC 11, INSERM UMR 1229-RMeS), Faculty of Dental Surgery, University of Nantes , Nantes, France
| | - Faleh Tamimi
- 1 Faculty of Dentistry, McGill University , Montreal, Canada
| |
Collapse
|
32
|
Smith CEL, Poulter JA, Antanaviciute A, Kirkham J, Brookes SJ, Inglehearn CF, Mighell AJ. Amelogenesis Imperfecta; Genes, Proteins, and Pathways. Front Physiol 2017; 8:435. [PMID: 28694781 PMCID: PMC5483479 DOI: 10.3389/fphys.2017.00435] [Citation(s) in RCA: 153] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 06/08/2017] [Indexed: 01/11/2023] Open
Abstract
Amelogenesis imperfecta (AI) is the name given to a heterogeneous group of conditions characterized by inherited developmental enamel defects. AI enamel is abnormally thin, soft, fragile, pitted and/or badly discolored, with poor function and aesthetics, causing patients problems such as early tooth loss, severe embarrassment, eating difficulties, and pain. It was first described separately from diseases of dentine nearly 80 years ago, but the underlying genetic and mechanistic basis of the condition is only now coming to light. Mutations in the gene AMELX, encoding an extracellular matrix protein secreted by ameloblasts during enamel formation, were first identified as a cause of AI in 1991. Since then, mutations in at least eighteen genes have been shown to cause AI presenting in isolation of other health problems, with many more implicated in syndromic AI. Some of the encoded proteins have well documented roles in amelogenesis, acting as enamel matrix proteins or the proteases that degrade them, cell adhesion molecules or regulators of calcium homeostasis. However, for others, function is less clear and further research is needed to understand the pathways and processes essential for the development of healthy enamel. Here, we review the genes and mutations underlying AI presenting in isolation of other health problems, the proteins they encode and knowledge of their roles in amelogenesis, combining evidence from human phenotypes, inheritance patterns, mouse models, and in vitro studies. An LOVD resource (http://dna2.leeds.ac.uk/LOVD/) containing all published gene mutations for AI presenting in isolation of other health problems is described. We use this resource to identify trends in the genes and mutations reported to cause AI in the 270 families for which molecular diagnoses have been reported by 23rd May 2017. Finally we discuss the potential value of the translation of AI genetics to clinical care with improved patient pathways and speculate on the possibility of novel treatments and prevention strategies for AI.
Collapse
Affiliation(s)
- Claire E L Smith
- Division of Oral Biology, School of Dentistry, St. James's University Hospital, University of LeedsLeeds, United Kingdom.,Section of Ophthalmology and Neuroscience, St. James's University Hospital, University of LeedsLeeds, United Kingdom
| | - James A Poulter
- Section of Ophthalmology and Neuroscience, St. James's University Hospital, University of LeedsLeeds, United Kingdom
| | - Agne Antanaviciute
- Section of Genetics, School of Medicine, St. James's University Hospital, University of LeedsLeeds, United Kingdom
| | - Jennifer Kirkham
- Division of Oral Biology, School of Dentistry, St. James's University Hospital, University of LeedsLeeds, United Kingdom
| | - Steven J Brookes
- Division of Oral Biology, School of Dentistry, St. James's University Hospital, University of LeedsLeeds, United Kingdom
| | - Chris F Inglehearn
- Section of Ophthalmology and Neuroscience, St. James's University Hospital, University of LeedsLeeds, United Kingdom
| | - Alan J Mighell
- Section of Ophthalmology and Neuroscience, St. James's University Hospital, University of LeedsLeeds, United Kingdom.,Oral Medicine, School of Dentistry, University of LeedsLeeds, United Kingdom
| |
Collapse
|
33
|
Ogbureke KUE, Koli K, Saxena G. Matrix Metalloproteinase 20 Co-expression With Dentin Sialophosphoprotein in Human and Monkey Kidneys. J Histochem Cytochem 2017; 64:623-36. [PMID: 27666430 DOI: 10.1369/0022155416665098] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Accepted: 07/26/2016] [Indexed: 11/22/2022] Open
Abstract
We recently reported the expression of matrix metalloproteinase 20 (MMP20), hitherto thought to be tooth specific, in the metabolically active ductal epithelial cells of human salivary glands. Furthermore, our report indicated that MMP20 co-expressed and potentially interacts with dentin sialophosphoprotein (DSPP), a member of the small integrin-binding ligand N-linked glycoproteins (SIBLINGs). Our earlier reports have shown the co-expression of three MMPs, MMP2, MMP3, and MMP9, with specific members of the SIBLING family: bone sialoprotein, osteopontin, and dentin matrix protein 1, respectively. This study investigated the expression of MMP20 and verified its co-expression with DSPP in human and monkey kidney sections and human mixed renal cells by IHC, in situ proximity ligation assay, and immunofluorescence. Our results show that MMP20 is expressed in all segments of the human and monkey nephron with marked intensity in the proximal and distal tubules, and was absent in the glomeruli. Furthermore, MMP20 co-expressed with DSPP in the proximal, distal, and collecting tubules, and in mixed renal cells. Consistent with other SIBLING-MMP pairs, the DSPP-MMP20 pair may play a role in the normal turnover of cell surface proteins and/or repair of pericellular matrix proteins of the basement membranes in the metabolically active duct epithelial system of the nephrons.
Collapse
Affiliation(s)
- Kalu U E Ogbureke
- Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas (KUEO, KK, GS)
| | - Komal Koli
- Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas (KUEO, KK, GS)
| | - Geetu Saxena
- Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas (KUEO, KK, GS)
| |
Collapse
|
34
|
MiR-153 Regulates Amelogenesis by Targeting Endocytotic and Endosomal/lysosomal Pathways-Novel Insight into the Origins of Enamel Pathologies. Sci Rep 2017; 7:44118. [PMID: 28287144 PMCID: PMC5347039 DOI: 10.1038/srep44118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 02/03/2017] [Indexed: 12/15/2022] Open
Abstract
Amelogenesis imperfecta (AI) is group of inherited disorders resulting in enamel pathologies. The involvement of epigenetic regulation in the pathogenesis of AI is yet to be clarified due to a lack of knowledge about amelogenesis. Our previous genome-wide microRNA and mRNA transcriptome analyses suggest a key role for miR-153 in endosome/lysosome-related pathways during amelogenesis. Here we show that miR-153 is significantly downregulated in maturation ameloblasts compared with secretory ameloblasts. Within ameloblast-like cells, upregulation of miR-153 results in the downregulation of its predicted targets including Cltc, Lamp1, Clcn4 and Slc4a4, and a number of miRNAs implicated in endocytotic pathways. Luciferase reporter assays confirmed the predicted interactions between miR-153 and the 3'-UTRs of Cltc, Lamp1 (in a prior study), Clcn4 and Slc4a4. In an enamel protein intake assay, enamel cells transfected with miR-153 show a decreased ability to endocytose enamel proteins. Finally, microinjection of miR-153 in the region of mouse first mandibular molar at postnatal day 8 (PN8) induced AI-like pathologies when the enamel development reached maturity (PN12). In conclusion, miR-153 regulates maturation-stage amelogenesis by targeting key genes involved in the endocytotic and endosomal/lysosomal pathways, and disruption of miR-153 expression is a potential candidate etiologic factor contributing to the occurrence of AI.
Collapse
|
35
|
Jiang T, Liu F, Wang WG, Jiang X, Wen X, Hu KJ, Xue Y. Distribution of Cathepsin K in Late Stage of Tooth Germ Development and Its Function in Degrading Enamel Matrix Proteins in Mouse. PLoS One 2017; 12:e0169857. [PMID: 28095448 PMCID: PMC5240959 DOI: 10.1371/journal.pone.0169857] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 12/25/2016] [Indexed: 01/24/2023] Open
Abstract
Cathepsin K (CTSK) is a member of cysteine proteinase family, and is predominantly expressed in osteoclastsfor degradationof bone matrix proteins. Given the similarity in physical properties of bone and dental mineralized tissues, including enamel, dentin and cementum, CTSK is likely to take part in mineralization process during odontogenesis. On the other hand, patients with pycnodysostosis caused by mutations of the CTSK gene displayedmultipledental abnormalities, such as hypoplasia of the enamel, obliterated pulp chambers, hypercementosis and periodontal disease. Thereforeitis necessary to study the metabolic role of CTSK in tooth matrix proteins. In this study, BALB/c mice at embryonic day 18 (E18), post-natal day 1 (P1), P5, P10 and P20 were used (5 mice at each time point)for systematic analyses of CTSK expression in the late stage of tooth germ development. We found that CTSK was abundantly expressed in the ameloblasts during secretory and maturation stages (P5 and P10) by immunohistochemistry stainings.During dentinogenesis, the staining was also intense in the mineralization stage (P5 and P10),but not detectable in the early stage of dentin formation (P1) and after tooth eruption (P20).Furthermore, through zymography and digestion test in vitro, CTSK was proved to be capable of hydrolyzing Emdogain and also cleaving Amelogenininto multiple products. Our resultsshed lights on revealing new functions of CTSK and pathogenesis of pycnodysostosis in oral tissues.
Collapse
Affiliation(s)
- Tao Jiang
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases &Shaanxi Clinical Research Center for Oral Diseases, Department of Oral and Maxillofacial Surgery, School of Stomatology, the Fourth Military Medical University, Xi’an, P. R. China
| | - Fen Liu
- Department of Periodontology, School of Stomatology, the Fourth Military Medical University, Xi’an, P. R. China
- Department of Stomatology, Northwest Women's and Children's Hospital, Xi’an, P. R. China
| | - Wei-Guang Wang
- Department of Cardiovascular Surgery, Xijing Hospital, the Fourth Military Medical University, Xi’an, P. R. China
- Medical Unit, Troops PLA, Liaocheng, P. R. China
| | - Xin Jiang
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases &Shaanxi Clinical Research Center for Oral Diseases, Department of Oral and Maxillofacial Surgery, School of Stomatology, the Fourth Military Medical University, Xi’an, P. R. China
- Department of Oral and Maxillofacial Surgery, Dongfeng Hospital, Hubei University of Medicine, Shiyan, P. R. China
| | - Xuan Wen
- Department of Prosthodontics, School of Stomatology, the Fourth Military Medical University, Xi’an, P. R. China
| | - Kai-Jin Hu
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases &Shaanxi Clinical Research Center for Oral Diseases, Department of Oral and Maxillofacial Surgery, School of Stomatology, the Fourth Military Medical University, Xi’an, P. R. China
- * E-mail: (YX); (KH)
| | - Yang Xue
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases &Shaanxi Clinical Research Center for Oral Diseases, Department of Oral and Maxillofacial Surgery, School of Stomatology, the Fourth Military Medical University, Xi’an, P. R. China
- * E-mail: (YX); (KH)
| |
Collapse
|
36
|
Margolis HC, Beniash E, Fowler CE. Role of Macromolecular Assembly of Enamel Matrix Proteins in Enamel Formation. J Dent Res 2016; 85:775-93. [PMID: 16931858 DOI: 10.1177/154405910608500902] [Citation(s) in RCA: 205] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Unlike other mineralized tissues, mature dental enamel is primarily (> 95% by weight) composed of apatitic crystals and has a unique hierarchical structure. Due to its high mineral content and organized structure, enamel has exceptional functional properties and is the hardest substance in the human body. Enamel formation (amelogenesis) is the result of highly orchestrated extracellular processes that regulate the nucleation, growth, and organization of forming mineral crystals. However, major aspects of the mechanism of enamel formation are not well-understood, although substantial evidence suggests that protein-protein and protein-mineral interactions play crucial roles in this process. The purpose of this review is a critical evaluation of the present state of knowledge regarding the potential role of the assembly of enamel matrix proteins in the regulation of crystal growth and the structural organization of the resulting enamel tissue. This review primarily focuses on the structure and function of amelogenin, the predominant enamel matrix protein. This review also provides a brief description of novel in vitro approaches that have used synthetic macromolecules ( i.e., surfactants and polymers) to regulate the formation of hierarchical inorganic (composite) structures in a fashion analogous to that believed to take place in biological systems, such as enamel. Accordingly, this review illustrates the potential for developing bio-inspired approaches to mineralized tissue repair and regeneration. In conclusion, the authors present a hypothesis, based on the evidence presented, that the full-length amelogenin uniquely regulates proper enamel formation through a process of cooperative mineralization, and not as a pre-formed matrix.
Collapse
Affiliation(s)
- H C Margolis
- Department of Biomineralization, The Forsyth Institute, 140 The Fenway, Boston, MA 02115, USA.
| | | | | |
Collapse
|
37
|
Yamaguti PM, Neves FDAR, Hotton D, Bardet C, de La Dure-Molla M, Castro LC, Scher MDC, Barbosa ME, Ditsch C, Fricain JC, de La Faille R, Figueres ML, Vargas-Poussou R, Houillier P, Chaussain C, Babajko S, Berdal A, Acevedo AC. Amelogenesis imperfecta in familial hypomagnesaemia and hypercalciuria with nephrocalcinosis caused by CLDN19 gene mutations. J Med Genet 2016; 54:26-37. [PMID: 27530400 DOI: 10.1136/jmedgenet-2016-103956] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 07/15/2016] [Accepted: 07/27/2016] [Indexed: 12/30/2022]
Abstract
BACKGROUND Amelogenesis imperfecta (AI) is a group of genetic diseases characterised by tooth enamel defects. AI was recently described in patients with familial hypercalciuria and hypomagnesaemia with nephrocalcinosis (FHHNC) caused by CLDN16 mutations. In the kidney, claudin-16 interacts with claudin-19 to control the paracellular passage of calcium and magnesium. FHHNC can be linked to mutations in both genes. Claudin-16 was shown to be expressed during amelogenesis; however, no data are available on claudin-19. Moreover, the enamel phenotype of patients with CLDN19 mutations has never been described. In this study, we describe the clinical and genetic features of nine patients with FHHNC carrying CLDN19 mutations and the claudin-19 expression profile in rat ameloblasts. METHODS Six FHHNC Brazilian patients were subjected to mutational analysis. Three additional French patients were recruited for orodental characterisation. The expression profile of claudin-19 was evaluated by RT-qPCR and immunofluorescence using enamel epithelium from rat incisors. RESULTS All patients presented AI at different degrees of severity. Two new likely pathogenic variations in CLDN19 were found: p.Arg200Gln and p.Leu90Arg. RT-qPCR revealed low Cldn19 expression in ameloblasts. Confocal analysis indicated that claudin-19 was immunolocalised at the distal poles of secretory and maturing ameloblasts. CONCLUSIONS For the first time, it was demonstrated that AI is associated with FHHNC in patients carrying CLDN19 mutations. The data suggest claudin-19 as an additional determinant in enamel formation. Indeed, the coexistence of hypoplastic and hypomineralised AI in the patients was consistent with claudin-19 expression in both secretory and maturation stages. Additional indirect systemic effects cannot be excluded.
Collapse
Affiliation(s)
- Paulo Marcio Yamaguti
- Faculty of Health Sciences, Division of Dentistry, Oral Care Center for Inherited Diseases, University Hospital of Brasilia, University of Brasilia, Brasilia, Brazil.,Faculty of Health Sciences, Laboratory of Oral Histopathology, University of Brasilia, Brasilia, Brazil
| | | | - Dominique Hotton
- Centre de Recherche des Cordeliers, University Paris-Diderot, INSERM UMR_S1138, Equipe Physiopathologie Orale Moléculaire, Paris, France
| | - Claire Bardet
- EA 2496, Laboratory Orofacial Pathologies, Imaging and Biotherapies, Dental School, University Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Muriel de La Dure-Molla
- INSERM UMR_S1163, Bases moléculaires et physiopathologiques des ostéochondrodysplasies, Institut Imagine, Necker, Paris, France.,AP-HP, Referral Center for Rare Buccal and Facial Dysmorphologies CRMR MAFACE, Hôpital Rothschild, Paris, France
| | - Luiz Claudio Castro
- Unit of Pediatric Endocrinology, University Hospital of Brasilia, Brasilia, Brazil
| | | | | | | | - Jean-Christophe Fricain
- CHU Bordeaux, Dental school, U1026 Tissue Bioengineering, University of Bordeaux/Inserm, Bordeaux, France
| | - Renaud de La Faille
- Department of Nephrology, Centre Hospitalier Universitaire de Bordeaux, Bordeaux, France
| | - Marie-Lucile Figueres
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138, Centre de Recherche des Cordeliers, CNRS ERL_8228, Paris, France
| | - Rosa Vargas-Poussou
- AP-HP, Department of Genetics, Reference Center of Children and Adult Renal Hereditary Diseases (MARHEA), Hôpital European Georges Pompidou, Paris, France
| | - Pascal Houillier
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138, Centre de Recherche des Cordeliers, CNRS ERL_8228, Paris, France.,AP-HP, Department of Genetics, Reference Center of Children and Adult Renal Hereditary Diseases (MARHEA), Hôpital European Georges Pompidou, Paris, France
| | - Catherine Chaussain
- EA 2496, Laboratory Orofacial Pathologies, Imaging and Biotherapies, Dental School, University Paris Descartes, Sorbonne Paris Cité, Paris, France.,AP-HP, Department of Genetics, Reference Center of Children and Adult Renal Hereditary Diseases (MARHEA), Hôpital European Georges Pompidou, Paris, France
| | - Sylvie Babajko
- Centre de Recherche des Cordeliers, University Paris-Diderot, INSERM UMR_S1138, Equipe Physiopathologie Orale Moléculaire, Paris, France
| | - Ariane Berdal
- Centre de Recherche des Cordeliers, University Paris-Diderot, INSERM UMR_S1138, Equipe Physiopathologie Orale Moléculaire, Paris, France.,AP-HP, Referral Center for Rare Buccal and Facial Dysmorphologies CRMR MAFACE, Hôpital Rothschild, Paris, France
| | - Ana Carolina Acevedo
- Faculty of Health Sciences, Division of Dentistry, Oral Care Center for Inherited Diseases, University Hospital of Brasilia, University of Brasilia, Brasilia, Brazil.,Faculty of Health Sciences, Laboratory of Oral Histopathology, University of Brasilia, Brasilia, Brazil
| |
Collapse
|
38
|
Mazumder P, Prajapati S, Bapat R, Moradian-Oldak J. Amelogenin-Ameloblastin Spatial Interaction around Maturing Enamel Rods. J Dent Res 2016; 95:1042-8. [PMID: 27146703 PMCID: PMC4959624 DOI: 10.1177/0022034516645389] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Amelogenin and ameloblastin are 2 extracellular matrix proteins that are essential for the proper development of enamel. We recently reported that amelogenin and ameloblastin colocalized during the secretory stage of enamel formation when nucleation of enamel crystallites occurs. Direct interactions between the 2 proteins have been also demonstrated in our in vitro studies. Here, we explore interactions between their fragments during enamel maturation. We applied in vivo immunofluorescence imaging, quantitative co-localization analysis, and a new FRET (fluorescence resonance energy transfer) technique to demonstrate ameloblastin and amelogenin interaction in the maturing mouse enamel. Using immunochemical analysis of protein samples extracted from 8-d-old (P8) first molars from mice as a model for maturation-stage enamel, we identified the ~17-kDa ameloblastin (Ambn-N) and the TRAP (tyrosine-rich amelogenin peptide) fragments. We used Ambn-N18 and Ambn-M300 antibodies raised against the N-terminal and C-terminal segments of ameloblastin, as well as Amel-FL and Amel-C19 antibodies against full-length recombinant mouse amelogenin (rM179) and C-terminal amelogenin, respectively. In transverse sections, co-localization images of N-terminal fragments of amelogenin and ameloblastin around the prism boundary revealed the "fish net" pattern of the enamel matrix. Using in vivo FRET microscopy, we further demonstrated spatial interactions between amelogenin and ameloblastin N-terminal fragments. In the maturing mouse enamel, the association of these residual protein fragments created a discontinuity between enamel rods, which we suggest is important for support and maintenance of enamel rods and eventual contribution to unique enamel mechanical properties. We present data that support cooperative functions of enamel matrix proteins in mediating the structural hierarchy of enamel and that contribute to our efforts to design and develop enamel biomimetic material.
Collapse
Affiliation(s)
- P Mazumder
- Center for Craniofacial Molecular Biology, Division of Biomedical Sciences, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
| | - S Prajapati
- Center for Craniofacial Molecular Biology, Division of Biomedical Sciences, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
| | - R Bapat
- Center for Craniofacial Molecular Biology, Division of Biomedical Sciences, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
| | - J Moradian-Oldak
- Center for Craniofacial Molecular Biology, Division of Biomedical Sciences, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
| |
Collapse
|
39
|
Murine matrix metalloproteinase-20 overexpression stimulates cell invasion into the enamel layer via enhanced Wnt signaling. Sci Rep 2016; 6:29492. [PMID: 27403713 PMCID: PMC4941722 DOI: 10.1038/srep29492] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 06/17/2016] [Indexed: 12/18/2022] Open
Abstract
Matrix metalloproteinase-20 (MMP20) is expressed by ameloblasts in developing teeth and MMP20 mutations cause enamel malformation. We established a stably transfected Tet-Off Mmp20-inducible ameloblast-lineage cell line and found that MMP20 expression promoted cell invasion. Previously, we engineered transgenic mice (Tg) that drive Mmp20 expression and showed that Mmp20(+/+)Tg mice had soft enamel. Here we asked if Mmp20 overexpression disrupts ameloblast function. Incisors from Mmp20(+/+) mice expressing the Mmp20 Tg had a striking cell infiltrate which nearly replaced the entire enamel layer. A thin layer of enamel-like material remained over the dentin and at the outer tooth surface, but between these regions were invading fibroblasts and epithelial cells that surrounded ectopic bone-like calcifications. Mmp20(+/+)Tg mice had decreased enamel organ cadherin levels compared to the Mmp20 ablated and WT mice and, instead of predominantly locating adjacent to the ameloblast cell membrane, β-catenin was predominantly present within the nuclei of invading cells. Our data suggest that increased cadherin cleavage by transgenic MMP20 in the WT background releases excess β-catenin, which translocates to ameloblast nuclei to promote cell migration/invasion. Therefore, we conclude that MMP20 plays a role in normal ameloblast migration through tightly controlled Wnt signaling and that MMP20 overexpression disrupts this process.
Collapse
|
40
|
Yoshimi Y, Kunimatsu R, Hirose N, Awada T, Miyauchi M, Takata T, Li W, Zhu L, Denbesten P, Tanne K, Tanimoto K. Effects of C-Terminal Amelogenin Peptide on Proliferation of Human Cementoblast Lineage Cells. J Periodontol 2016; 87:820-7. [DOI: 10.1902/jop.2016.150507] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
41
|
Bourd-Boittin K, Septier D, Hall R, Goldberg M, Menashi S. Immunolocalization of Enamelysin (Matrix Metalloproteinase-20) in the Forming Rat Incisor. J Histochem Cytochem 2016; 52:437-45. [PMID: 15033995 DOI: 10.1177/002215540405200402] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In the rat model, we used the continuously growing incisor to study the expression pattern of matrix metalloproteinase-20 (MMP-20) during the formation of mineralized dental tissues. Casein zymography analysis of extracts of the forming part of the incisor revealed lysis bands corresponding to both the latent form at 57 kD and the active 46- and 41-kD forms, whereas omission of proteinase inhibitors during protein extraction resulted in a single band at 21 kD. A higher molecular weight form of 78 kD was also stained with MMP-20 and TIMP-2 antibodies in Western blotting, and was therefore believed to correspond to an MMP-20/TIMP-2 complex. Immunohistochemical and immunogold electron microscopic results demonstrated strong MMP-20 staining in the forming outer enamel, which diminished near the dentino-enamel junction, but dentin and predentin were unstained. A strong concentration of MMP-20 was seen in the stratum intermedium (SI), particularly at the earlier stages of enamel development. Our results confirm the presence of MMP-20 protein in ameloblasts and odontoblasts of rat incisor and show it to be localized in the same sites of the forming enamel as amelogenin. Their expression is transient in odontoblasts but persists in ameloblasts, and in both cases the expression of amelogenin preceded that of MMP-20 suggesting a developmentally controlled regulation.
Collapse
Affiliation(s)
- Katia Bourd-Boittin
- Matrices Extracellulaires et Biominéralisation, EA 2496, Faculté de Chirurgie Dentaire, Université René Descartes Paris V, Montrouge, France
| | | | | | | | | |
Collapse
|
42
|
Abstract
Interactions between enamel matrix proteins are important
for enamel biomineralization. In recent in situ studies, we
showed that the N-terminal proteolytic product of ameloblastin co-localized with
amelogenin around the prism boundaries. However, the molecular mechanisms of such
interactions are still unclear. Here, in order to determine the interacting domains
between amelogenin and ameloblastin, we designed four ameloblastin peptides derived
from different regions of the full-length protein (AB1, AB2 and AB3 at N-terminus,
and AB6 at C-terminus) and studied their interactions with recombinant amelogenin
(rP172), and the tyrosine-rich amelogenin polypeptide (TRAP). A series of amelogenin
Trp variants (rP172(W25), rP172(W45) and rP172(W161)) were also used for intrinsic
fluorescence spectroscopy. Fluorescence spectra of rP172 titrated with AB3, a peptide
encoded by exon 5 of ameloblastin, showed a shift in λmax in a
dose-dependent manner, indicating molecular interactions in the region encoded by
exon 5 of ameloblastin. Circular dichroism (CD) spectra of amelogenin titrated with
AB3 showed that amelogenin was responsible for forming α-helix in the presence of
ameloblastin. Fluorescence spectra of amelogenin Trp variants as well as the spectra
of TRAP titrated with AB3 showed that the N-terminus of amelogenin is involved in the
interaction between ameloblastin and amelogenin. We suggest that macromolecular
co-assembly between amelogenin and ameloblastin may play important roles in enamel
biomineralization. An in vitro approach to study
ameloblastin-amelogenin interactions is presented. Intrinsic fluorescence of tryptophan and Circular Dichroism
were utilized. We report that amelogenin has ameloblastin-binding ability
via its N-terminal close to Trp 25. We report that ameloblastin has amelogenin-binding ability
via a peptide encoded by exon 5. Macromolecular co-assembly between amelogenin and
ameloblastin may play important roles in enamel biomineralization.
Collapse
|
43
|
Kunimatsu R, Yoshimi Y, Hirose N, Awada T, Miyauchi M, Takata T, Li W, Zhu L, Denbesten P, Tanimoto K. The C-terminus of amelogenin enhances osteogenic differentiation of human cementoblast lineage cells. J Periodontal Res 2016; 52:218-224. [DOI: 10.1111/jre.12384] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/04/2016] [Indexed: 12/28/2022]
Affiliation(s)
- R. Kunimatsu
- Department of Orthodontics; Applied Life Sciences; Hiroshima University; Institute of Biomedical & Health Sciences; Hiroshima Japan
| | - Y. Yoshimi
- Department of Orthodontics; Applied Life Sciences; Hiroshima University; Institute of Biomedical & Health Sciences; Hiroshima Japan
| | - N. Hirose
- Department of Orthodontics; Applied Life Sciences; Hiroshima University; Institute of Biomedical & Health Sciences; Hiroshima Japan
| | - T. Awada
- Department of Orthodontics; Applied Life Sciences; Hiroshima University; Institute of Biomedical & Health Sciences; Hiroshima Japan
| | - M. Miyauchi
- Department of Oral Maxillofacial and Pathobiology; Basic Life Sciences; Hiroshima University; Institute of Biomedical & Health Sciences; Hiroshima Japan
| | - T. Takata
- Department of Oral Maxillofacial and Pathobiology; Basic Life Sciences; Hiroshima University; Institute of Biomedical & Health Sciences; Hiroshima Japan
| | - W. Li
- Department of Orofacial Sciences; University of California; San Francisco CA USA
| | - L. Zhu
- Department of Orofacial Sciences; University of California; San Francisco CA USA
| | - P.K. Denbesten
- Department of Orofacial Sciences; University of California; San Francisco CA USA
| | - K. Tanimoto
- Department of Orthodontics; Applied Life Sciences; Hiroshima University; Institute of Biomedical & Health Sciences; Hiroshima Japan
| |
Collapse
|
44
|
Amyloid-like ribbons of amelogenins in enamel mineralization. Sci Rep 2016; 6:23105. [PMID: 27009419 PMCID: PMC4806362 DOI: 10.1038/srep23105] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 02/29/2016] [Indexed: 12/27/2022] Open
Abstract
Enamel, the outermost layer of teeth, is an acellular mineralized tissue that cannot regenerate; the mature tissue is composed of high aspect ratio apatite nanocrystals organized into rods and inter-rod regions. Amelogenin constitutes 90% of the protein matrix in developing enamel and plays a central role in guiding the hierarchical organization of apatite crystals observed in mature enamel. To date, a convincing link between amelogenin supramolecular structures and mature enamel has yet to be described, in part because the protein matrix is degraded during tissue maturation. Here we show compelling evidence that amelogenin self-assembles into an amyloid-like structure in vitro and in vivo. We show that enamel matrices stain positive for amyloids and we identify a specific region within amelogenin that self-assembles into β-sheets. We propose that amelogenin nanoribbons template the growth of apatite mineral in human enamel. This is a paradigm shift from the current model of enamel development.
Collapse
|
45
|
Bardet C, Courson F, Wu Y, Khaddam M, Salmon B, Ribes S, Thumfart J, Yamaguti PM, Rochefort GY, Figueres ML, Breiderhoff T, Garcia-Castaño A, Vallée B, Le Denmat D, Baroukh B, Guilbert T, Schmitt A, Massé JM, Bazin D, Lorenz G, Morawietz M, Hou J, Carvalho-Lobato P, Manzanares MC, Fricain JC, Talmud D, Demontis R, Neves F, Zenaty D, Berdal A, Kiesow A, Petzold M, Menashi S, Linglart A, Acevedo AC, Vargas-Poussou R, Müller D, Houillier P, Chaussain C. Claudin-16 Deficiency Impairs Tight Junction Function in Ameloblasts, Leading to Abnormal Enamel Formation. J Bone Miner Res 2016; 31:498-513. [PMID: 26426912 DOI: 10.1002/jbmr.2726] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 09/28/2015] [Accepted: 09/29/2015] [Indexed: 12/26/2022]
Abstract
Claudin-16 protein (CLDN16) is a component of tight junctions (TJ) with a restrictive distribution so far demonstrated mainly in the kidney. Here, we demonstrate the expression of CLDN16 also in the tooth germ and show that claudin-16 gene (CLDN16) mutations result in amelogenesis imperfecta (AI) in the 5 studied patients with familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC). To investigate the role of CLDN16 in tooth formation, we studied a murine model of FHHNC and showed that CLDN16 deficiency led to altered secretory ameloblast TJ structure, lowering of extracellular pH in the forming enamel matrix, and abnormal enamel matrix protein processing, resulting in an enamel phenotype closely resembling human AI. This study unravels an association of FHHNC owing to CLDN16 mutations with AI, which is directly related to the loss of function of CLDN16 during amelogenesis. Overall, this study indicates for the first time the importance of a TJ protein in tooth formation and underlines the need to establish a specific dental follow-up for these patients.
Collapse
Affiliation(s)
- Claire Bardet
- EA 2496, Laboratory Orofacial Pathologies, Imaging and Biotherapies, Dental School Paris Descartes University, Sorbonne Paris Cité, France
| | - Frédéric Courson
- Department of Odontology, AP-HP, and Reference Center for Rare Diseases of the Metabolism of Calcium and Phosphorus, Nord Val de Seine Hospital, Bretonneau, France
| | - Yong Wu
- EA 2496, Laboratory Orofacial Pathologies, Imaging and Biotherapies, Dental School Paris Descartes University, Sorbonne Paris Cité, France.,Department of Oral and Cranio-maxillofacial Science, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Mayssam Khaddam
- EA 2496, Laboratory Orofacial Pathologies, Imaging and Biotherapies, Dental School Paris Descartes University, Sorbonne Paris Cité, France
| | - Benjamin Salmon
- EA 2496, Laboratory Orofacial Pathologies, Imaging and Biotherapies, Dental School Paris Descartes University, Sorbonne Paris Cité, France.,Department of Odontology, AP-HP, and Reference Center for Rare Diseases of the Metabolism of Calcium and Phosphorus, Nord Val de Seine Hospital, Bretonneau, France
| | - Sandy Ribes
- EA 2496, Laboratory Orofacial Pathologies, Imaging and Biotherapies, Dental School Paris Descartes University, Sorbonne Paris Cité, France
| | - Julia Thumfart
- Department of Pediatric Nephrology, Charité University School of Medicine, Berlin, Germany
| | - Paulo M Yamaguti
- Division of Dentistry, Oral Care Center for Inherited Diseases, University Hospital of Brasilia, Faculty of Health Sciences, University of Brasilia (UnB), Brasilia, Brazil
| | - Gael Y Rochefort
- EA 2496, Laboratory Orofacial Pathologies, Imaging and Biotherapies, Dental School Paris Descartes University, Sorbonne Paris Cité, France
| | - Marie-Lucile Figueres
- INSERM UMRS 1138, Cordeliers Research Center, Paris-Diderot, Pierre et Marie Curie and Paris Descartes Universities, CNRS ERL 8228, Paris, France
| | - Tilman Breiderhoff
- Department of Pediatric Nephrology, Charité University School of Medicine, Berlin, Germany
| | - Alejandro Garcia-Castaño
- Department of Genetics, AP-HP, and Reference Center of Children and Adult Renal Hereditary Diseases (MARHEA), European Hospital Georges Pompidou, Paris, France
| | - Benoit Vallée
- Laboratory CRRET, Paris-Est University, CNRS, Créteil, France
| | - Dominique Le Denmat
- EA 2496, Laboratory Orofacial Pathologies, Imaging and Biotherapies, Dental School Paris Descartes University, Sorbonne Paris Cité, France
| | - Brigitte Baroukh
- EA 2496, Laboratory Orofacial Pathologies, Imaging and Biotherapies, Dental School Paris Descartes University, Sorbonne Paris Cité, France
| | - Thomas Guilbert
- Cochin Institute, Plate-Forme d'Imagerie Photonique, INSERM U1016, CNRS UMR8104, Paris Descartes University Sorbonne Paris Cité, Paris, France
| | - Alain Schmitt
- Cochin Institute, Transmission Electron Microscopy Platform, INSERM U1016, CNRS UMR8104, Paris Descartes University Sorbonne Paris Cité, Paris, France
| | - Jean-Marc Massé
- Cochin Institute, Transmission Electron Microscopy Platform, INSERM U1016, CNRS UMR8104, Paris Descartes University Sorbonne Paris Cité, Paris, France
| | - Dominique Bazin
- Laboratoire de Physique des Solides, CNRS, Paris Sud University, Orsay, and LCMCP-UPMC, Collège de France, Paris, France
| | - Georg Lorenz
- Fraunhofer Institute for Mechanics of Materials IWM, Halle, Germany
| | - Maria Morawietz
- Fraunhofer Institute for Mechanics of Materials IWM, Halle, Germany
| | - Jianghui Hou
- Division of Renal Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Patricia Carvalho-Lobato
- Human Anatomy and Embryology, Health University of Barcelona Campus-Bellvitge, University of Barcelona, Barcelona, Spain
| | - Maria Cristina Manzanares
- Human Anatomy and Embryology, Health University of Barcelona Campus-Bellvitge, University of Barcelona, Barcelona, Spain
| | - Jean-Christophe Fricain
- CHU Bordeaux, Dental School, U1026 Tissue Bioengineering, University of Bordeaux/Inserm, Bordeaux, France
| | - Deborah Talmud
- Department of Pediatrics, Centre Hospitalier Régional (CHR) d'Orléans, Orleans, France
| | | | - Francisco Neves
- Laboratory of Molecular Pharmacology, Faculty of Health Sciences, University of Brasilia (UNB), Brasilia, Brazil
| | - Delphine Zenaty
- Department of Pediatric Endocrinology, AP-HP, Paris Diderot University, Robert Debré Hospital, Paris, France
| | - Ariane Berdal
- INSERM UMRS 1138, Cordeliers Research Center, Paris-Diderot, Pierre et Marie Curie and Paris Descartes Universities, CNRS ERL 8228, Paris, France
| | - Andreas Kiesow
- Fraunhofer Institute for Mechanics of Materials IWM, Halle, Germany
| | - Matthias Petzold
- Fraunhofer Institute for Mechanics of Materials IWM, Halle, Germany
| | - Suzanne Menashi
- Laboratory CRRET, Paris-Est University, CNRS, Créteil, France
| | - Agnes Linglart
- Department of Pediatric Endocrinology, AP-HP, Paris Sud University, School of Medicine, and Reference Center for Rare Diseases of the Metabolism of Calcium and Phosphorus, Paris, France
| | - Ana Carolina Acevedo
- Division of Dentistry, Oral Care Center for Inherited Diseases, University Hospital of Brasilia, Faculty of Health Sciences, University of Brasilia (UnB), Brasilia, Brazil
| | - Rosa Vargas-Poussou
- Department of Genetics, AP-HP, and Reference Center of Children and Adult Renal Hereditary Diseases (MARHEA), European Hospital Georges Pompidou, Paris, France
| | - Dominik Müller
- Department of Pediatric Nephrology, Charité University School of Medicine, Berlin, Germany
| | - Pascal Houillier
- INSERM UMRS 1138, Cordeliers Research Center, Paris-Diderot, Pierre et Marie Curie and Paris Descartes Universities, CNRS ERL 8228, Paris, France.,Department of Physiology, AP-HP, and Reference Center of Children and Adult Renal Hereditary Diseases (MARHEA), Georges Pompidou European Hospital, Paris, France
| | - Catherine Chaussain
- EA 2496, Laboratory Orofacial Pathologies, Imaging and Biotherapies, Dental School Paris Descartes University, Sorbonne Paris Cité, France.,Department of Odontology, AP-HP, and Reference Center for Rare Diseases of the Metabolism of Calcium and Phosphorus, Nord Val de Seine Hospital, Bretonneau, France
| |
Collapse
|
46
|
Boskey AL, Villarreal-Ramirez E. Intrinsically disordered proteins and biomineralization. Matrix Biol 2016; 52-54:43-59. [PMID: 26807759 DOI: 10.1016/j.matbio.2016.01.007] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 01/19/2016] [Accepted: 01/19/2016] [Indexed: 01/21/2023]
Abstract
In vertebrates and invertebrates, biomineralization is controlled by the cell and the proteins they produce. A large number of these proteins are intrinsically disordered, gaining some secondary structure when they interact with their binding partners. These partners include the component ions of the mineral being deposited, the crystals themselves, the template on which the initial crystals form, and other intrinsically disordered proteins and peptides. This review speculates why intrinsically disordered proteins are so important for biomineralization, providing illustrations from the SIBLING (small integrin binding N-glycosylated) proteins and their peptides. It is concluded that the flexible structure, and the ability of the intrinsically disordered proteins to bind to a multitude of surfaces is crucial, but details on the precise-interactions, energetics and kinetics of binding remain to be determined.
Collapse
Affiliation(s)
- Adele L Boskey
- Musculoskeletal Integrity Program, Hospital for Special Surgery, New York, NY 10021, USA.
| | | |
Collapse
|
47
|
Prajapati S, Tao J, Ruan Q, De Yoreo JJ, Moradian-Oldak J. Matrix metalloproteinase-20 mediates dental enamel biomineralization by preventing protein occlusion inside apatite crystals. Biomaterials 2016; 75:260-270. [PMID: 26513418 PMCID: PMC4654413 DOI: 10.1016/j.biomaterials.2015.10.031] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 10/07/2015] [Accepted: 10/14/2015] [Indexed: 11/25/2022]
Abstract
Reconstruction of enamel-like materials is a central topic of research in dentistry and material sciences. The importance of precise proteolytic mechanisms in amelogenesis to form a hard tissue with more than 95% mineral content has already been reported. A mutation in the Matrix Metalloproteinase-20 (MMP-20) gene results in hypomineralized enamel that is thin, disorganized and breaks from the underlying dentin. We hypothesized that the absence of MMP-20 during amelogenesis results in the occlusion of amelogenin in the enamel hydroxyapatite crystals. We used spectroscopy and electron microscopy techniques to qualitatively and quantitatively analyze occluded proteins within the isolated enamel crystals from MMP-20 null and Wild type (WT) mice. Our results showed that the isolated enamel crystals of MMP-20 null mice had more organic macromolecules occluded inside them than enamel crystals from the WT. The crystal lattice arrangements of MMP-20 null enamel crystals analyzed by High Resolution Transmission Electron Microscopy (HRTEM) were found to be significantly different from those of the WT. Raman studies indicated that the crystallinity of the MMP-20 null enamel crystals was lower than that of the WT. In conclusion, we present a novel functional mechanism of MMP-20, specifically prevention of unwanted organic material entrapped in the forming enamel crystals, which occurs as the result of precise amelogenin cleavage. MMP-20 action guides the growth morphology of the forming hydroxyapatite crystals and enhances their crystallinity. Elucidating such molecular mechanisms can be applied in the design of novel biomaterials for future clinical applications in dental restoration or repair.
Collapse
Affiliation(s)
- Saumya Prajapati
- University of Southern California, Herman Ostrow School of Dentistry, Division of Biomedical Sciences, Center for Craniofacial Molecular Biology, Los Angeles, CA 90033, USA
| | - Jinhui Tao
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Qichao Ruan
- University of Southern California, Herman Ostrow School of Dentistry, Division of Biomedical Sciences, Center for Craniofacial Molecular Biology, Los Angeles, CA 90033, USA
| | - James J De Yoreo
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Janet Moradian-Oldak
- University of Southern California, Herman Ostrow School of Dentistry, Division of Biomedical Sciences, Center for Craniofacial Molecular Biology, Los Angeles, CA 90033, USA.
| |
Collapse
|
48
|
Miller RJ. The Use of Enamel Matrix Derivative in Two-Stage Guided Bone Regeneration Procedures. Clin Adv Periodontics 2015; 5:184-191. [DOI: 10.1902/cap.2014.130098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 01/27/2014] [Indexed: 11/13/2022]
|
49
|
Wyganowska-Świątkowska M, Urbaniak P, Nohawica MM, Kotwicka M, Jankun J. Enamel matrix proteins exhibit growth factor activity: A review of evidence at the cellular and molecular levels. Exp Ther Med 2015; 9:2025-2033. [PMID: 26161150 DOI: 10.3892/etm.2015.2414] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 03/25/2015] [Indexed: 01/23/2023] Open
Abstract
Enamel matrix derivative (EMD) is a commercially available protein extract, mainly comprising amelogenins. A number of other polypeptides have been identified in EMD, mostly growth factors, which promote cementogenesis and osteogenesis during the regeneration processes through the regulation of cell proliferation, differentiation and activity; however, not all of their functions are clear. Enamel extracts have been proposed to have numerous activities such as bone morphogenetic protein- and transforming growth factor β (TGF-β)-like activity, and activities similar to those of insulin-like growth factor, fibroblast growth factor, platelet-derived growth factor, vascular endothelial growth factor and epidermal growth factor. These activities have been observed at the molecular and cellular levels and in numerous animal models. Furthermore, it has been suggested that EMD contains an unidentified biologically active factor that acts in combination with TGF-β1, and several studies have reported functional similarities between growth factors and TGF-β in cellular processes. The effects of enamel extracts on the cell cycle and biology are summarized and discussed in this review.
Collapse
Affiliation(s)
| | - Paulina Urbaniak
- Department of Cell Biology, Poznan University of Medical Sciences, Poznań 60-806, Poland
| | | | - Małgorzata Kotwicka
- Department of Cell Biology, Poznan University of Medical Sciences, Poznań 60-806, Poland
| | - Jerzy Jankun
- Department of Urology, Urology Research Centre, College of Medicine, University of Toledo, Toledo, OH 43614, USA ; Protein Research Chair, Department of Biochemistry, College of Sciences, King Saud University, Riyadh 11451, Kingdom of Saudi Arabia ; Department of Clinical Nutrition, Medical University of Gdańsk, Gdańsk 80-211, Poland
| |
Collapse
|
50
|
Saxena G, Koli K, de la Garza J, Ogbureke K. Matrix Metalloproteinase 20–Dentin Sialophosphoprotein Interaction in Oral Cancer. J Dent Res 2015; 94:584-93. [DOI: 10.1177/0022034515570156] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Matrix metalloproteinase 20 (MMP-20), widely regarded as tooth specific, participates with MMP-2 in processing dentin sialophosphoprotein (DSPP) into dentin sialoprotein, dentin phosphoprotein, and dentin glycoprotein. In biochemical system, MMP-2, MMP-3, and MMP-9 bind with high affinity to, and are activated by, specific small integrin-binding ligand N-linked glycoproteins (SIBLINGs): bone sialoprotein, osteopontin, and dentin matrix protein 1, respectively. Subsequent reports documented possible biological relevance of SIBLING-MMP interaction in vivo by showing that SIBLINGs are always coexpressed with their MMP partners. However, the cognate MMPs for 2 other SIBLINGs—DSPP and matrix extracellular phosphogylcoprotein—are yet to be identified. Our goal was to investigate MMP-20 expression and to explore preliminary evidence of its interaction with DSPP in oral squamous cell carcinomas (OSCCs). Immunohistochemistry analysis of sections from 21 cases of archived human OSCC tissues showed immunoreactivity for MMP-20 in 18 (86%) and coexpression with DSPP in all 15 cases (71%) positive for DSPP. Similarly, 28 (93%) of 30 cases of oral epithelial dysplasia were positive for MMP-20. Western blot and quantitative real-time polymerase chain reaction analysis on OSCC cell lines showed upregulation of MMP-20 protein and mRNA, respectively, while immunofluorescence showed coexpression of MMP-20 and DSPP. Colocalization and potential interaction of MMP-20 with dentin sialoprotein was confirmed by coimmunoprecipitation and mass spectrometry analysis of immunoprecipitation product from OSCC cell lysate, and in situ proximity ligation assays. Significantly, results of chromatin immunoprecipation revealed a 9-fold enrichment of DSPP at MMP-20 promoter–proximal elements. Our data provide evidence that MMP-20 has a wider tissue distribution than previously acknowledged. MMP-20–DSPP specific interaction, excluding other MMP-20–SIBLING pairings, identifies MMP-20 as DSPP cognate MMP. Furthermore, the strong DSPP enrichment at the MMP-20 promoter suggests a regulatory role in MMP-20 transcription. These novel findings provide the foundation to explore the mechanisms and significance of DSPP-MMP-20 interaction in oral carcinogenesis.
Collapse
Affiliation(s)
- G. Saxena
- Department of Diagnostic and Biomedical Sciences, The University of Texas School of Dentistry at Houston, Houston, TX, USA
| | - K. Koli
- Department of Diagnostic and Biomedical Sciences, The University of Texas School of Dentistry at Houston, Houston, TX, USA
| | - J. de la Garza
- Department of Diagnostic and Biomedical Sciences, The University of Texas School of Dentistry at Houston, Houston, TX, USA
| | - K.U.E. Ogbureke
- Department of Diagnostic and Biomedical Sciences, The University of Texas School of Dentistry at Houston, Houston, TX, USA
| |
Collapse
|