1
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Zhang T, Wu L, Song Y, Li X, Niu X, Sun Y, Liu J, Feng G, Lei S. Functional Covalent Organic Framework (COF) Nanoparticles for Biomimic Mineralization and Bacteria Inhabitation. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 37919250 DOI: 10.1021/acsami.3c13249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2023]
Abstract
Biomimic mineralization of hard tissues with hierarchical structures is a challenging task, while designing multifunctional materials possessing both the ability of biomimic mineralization and drug delivery is even more difficult. Herein, inspired by the multilevel structure and mineralization ability of amelogenin, a novel carboxyl-functionalized covalent organic framework (COF) nanosphere material was designed and synthesized, which exhibited a significant biomimetic remineralization ability as demonstrated on SiO2 glass, Ti6Al4V, and an acid-etched enamel surface. Furthermore, the nanoporous structure also enables the COF nanospheres to serve as a drug delivery system for the controlled release of antibacterial drugs. This work provides a promising strategy for the design of multifunctional biomimic materials.
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Affiliation(s)
- Tian Zhang
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University & Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Lingli Wu
- Medical College, Northwest Minzu University, Lanzhou 730000, China
| | - Yaru Song
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University & Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Xiaojuan Li
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University & Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Xinxin Niu
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University & Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Yajing Sun
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University & Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Jie Liu
- Tianjin Key Laboratory of Life and Health Detection, Life and Health Intelligent Research Institute, Tianjin University of Technology, Tianjin 300384, China
| | - Guangyuan Feng
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University & Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Shengbin Lei
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University & Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
- School of Chemistry and Chemical Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
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2
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Shao C, Bapat RA, Su J, Moradian-Oldak J. Regulation of Hydroxyapatite Nucleation In Vitro through Ameloblastin-Amelogenin Interactions. ACS Biomater Sci Eng 2023; 9:1834-1842. [PMID: 35068157 PMCID: PMC9308824 DOI: 10.1021/acsbiomaterials.1c01113] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Amelogenin (Amel) and ameloblastin (Ambn) are two primary extracellular enamel matrix proteins that play crucial roles for proper thickness, prismatic structure, and robust mechanical properties. Previous studies have shown that Amel and Ambn bind to each other, but the effect of their coassembly on the nucleation of hydroxyapatite (HAP) is unclear. Here, we systematically investigated the coassembly of recombinant mouse Amel and Ambn in various ratios using in situ atomic force microscopy, dynamic light scattering, and transmission electron microscopy. The size of protein particles decreased as the Ambn:Amel ratio increased. To define the coassembly domain on Ambn, we used Ambn-derived peptides and Ambn variants to examine their effects on the amelogenin particle size distribution. We found that the peptide sequence encoded by exon 5 of Ambn affected Amel self-assembly but the variant lacking this sequence did not have any effect on Amel self-assembly. Furthermore, through monitoring the pH change in bulk mineralization solution, we tracked the nucleation behavior of HAP in the presence of Ambn and Amel and found that their coassemblies at different ratios showed varying abilities to stabilize amorphous calcium phosphate. These results demonstrated that Ambn and Amel coassemble with each other via a motif within the sequence encoded by exon 5 of Ambn and cooperate in regulating the nucleation of HAP crystals, enhancing our understanding of the important role of enamel matrix proteins in amelogenesis.
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Affiliation(s)
- Changyu Shao
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, 2250 Alcazar Street, Los Angeles, California 90033, United States
| | - Rucha Arun Bapat
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, 2250 Alcazar Street, Los Angeles, California 90033, United States
| | - Jingtan Su
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, 2250 Alcazar Street, Los Angeles, California 90033, United States
| | - Janet Moradian-Oldak
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, 2250 Alcazar Street, Los Angeles, California 90033, United States
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3
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Zhang Y, Jin T, Zhu W, Pandya M, Gopinathan G, Allen M, Reed D, Keiderling T, Liao X, Diekwisch TGH. Highly acidic pH facilitates enamel protein self-assembly, apatite crystal growth and enamel protein interactions in the early enamel matrix. Front Physiol 2022; 13:1019364. [PMID: 36569763 PMCID: PMC9772882 DOI: 10.3389/fphys.2022.1019364] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 11/22/2022] [Indexed: 12/13/2022] Open
Abstract
Tooth enamel develops within a pH sensitive amelogenin-rich protein matrix. The purpose of the present study is to shed light on the intimate relationship between enamel matrix pH, enamel protein self-assembly, and enamel crystal growth during early amelogenesis. Universal indicator dye staining revealed highly acidic pH values (pH 3-4) at the exocytosis site of secretory ameloblasts. When increasing the pH of an amelogenin solution from pH 5 to pH 7, there was a gradual increase in subunit compartment size from 2 nm diameter subunits at pH 5 to a stretched configuration at pH6 and to 20 nm subunits at pH 7. HSQC NMR spectra revealed that the formation of the insoluble amelogenin self-assembly structure at pH6 was critically mediated by at least seven of the 11 histidine residues of the amelogenin coil domain (AA 46-117). Comparing calcium crystal growth on polystyrene plates, crystal length was more than 20-fold elevated at pH 4 when compared to crystals grown at pH 6 or pH 7. To illustrate the effect of pH on enamel protein self-assembly at the site of initial enamel formation, molar teeth were immersed in phosphate buffer at pH4 and pH7, resulting in the formation of intricate berry tree-like assemblies surrounding initial enamel crystal assemblies at pH4 that were not evident at pH7 nor in citrate buffer. Amelogenin and ameloblastin enamel proteins interacted at the secretory ameloblast pole and in the initial enamel layer, and co-immunoprecipitation studies revealed that this amelogenin/ameloblastin interaction preferentially takes place at pH 4-pH 4.5. Together, these studies highlight the highly acidic pH of the very early enamel matrix as an essential contributing factor for enamel protein structure and self-assembly, apatite crystal growth, and enamel protein interactions.
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Affiliation(s)
- Youbin Zhang
- Department of Oral Biology, University of Illinois at Chicago, Dallas, Illinois, United States
| | - Tianquan Jin
- Department of Oral Biology, University of Illinois at Chicago, Dallas, Illinois, United States
| | - Weiying Zhu
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois, United States
| | - Mirali Pandya
- Center for Craniofacial Research and Diagnosis, Texas A and M College of Dentistry, Dallas, Texas, United States
| | - Gokul Gopinathan
- Center for Craniofacial Research and Diagnosis, Texas A and M College of Dentistry, Dallas, Texas, United States
| | - Michael Allen
- Department of Medicine, University of Chicago, Chicago, Illinois, United States
| | - David Reed
- Department of Oral Biology, University of Illinois at Chicago, Dallas, Illinois, United States
| | - Timothy Keiderling
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois, United States,*Correspondence: Timothy Keiderling, ; Xiubei Liao, ; Thomas G. H. Diekwisch,
| | - Xiubei Liao
- Department of Biochemistry, University of Illinois at Chicago, Chicago, Illinois, United States,*Correspondence: Timothy Keiderling, ; Xiubei Liao, ; Thomas G. H. Diekwisch,
| | - Thomas G. H. Diekwisch
- Department of Oral Biology, University of Illinois at Chicago, Dallas, Illinois, United States,Center for Craniofacial Research and Diagnosis, Texas A and M College of Dentistry, Dallas, Texas, United States,*Correspondence: Timothy Keiderling, ; Xiubei Liao, ; Thomas G. H. Diekwisch,
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4
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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
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5
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Loss of biological control of enamel mineralization in amelogenin-phosphorylation-deficient mice. J Struct Biol 2022; 214:107844. [DOI: 10.1016/j.jsb.2022.107844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/18/2022] [Accepted: 02/22/2022] [Indexed: 11/23/2022]
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6
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Danesi AL, Athanasiadou D, Mansouri A, Phen A, Neshatian M, Holcroft J, Bonde J, Ganss B, Carneiro KMM. Uniaxial Hydroxyapatite Growth on a Self-Assembled Protein Scaffold. Int J Mol Sci 2021; 22:12343. [PMID: 34830225 PMCID: PMC8620880 DOI: 10.3390/ijms222212343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 11/16/2022] Open
Abstract
Biomineralization is a crucial process whereby organisms produce mineralized tissues such as teeth for mastication, bones for support, and shells for protection. Mineralized tissues are composed of hierarchically organized hydroxyapatite crystals, with a limited capacity to regenerate when demineralized or damaged past a critical size. Thus, the development of protein-based materials that act as artificial scaffolds to guide hydroxyapatite growth is an attractive goal both for the design of ordered nanomaterials and for tissue regeneration. In particular, amelogenin, which is the main protein that scaffolds the hierarchical organization of hydroxyapatite crystals in enamel, amelogenin recombinamers, and amelogenin-derived peptide scaffolds have all been investigated for in vitro mineral growth. Here, we describe uniaxial hydroxyapatite growth on a nanoengineered amelogenin scaffold in combination with amelotin, a mineral promoting protein present during enamel formation. This bio-inspired approach for hydroxyapatite growth may inform the molecular mechanism of hydroxyapatite formation in vitro as well as possible mechanisms at play during mineralized tissue formation.
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Affiliation(s)
- Alexander L. Danesi
- Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1G6, Canada; (A.L.D.); (D.A.); (A.M.); (A.P.); (M.N.); (J.H.); (B.G.)
| | - Dimitra Athanasiadou
- Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1G6, Canada; (A.L.D.); (D.A.); (A.M.); (A.P.); (M.N.); (J.H.); (B.G.)
| | - Ahmad Mansouri
- Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1G6, Canada; (A.L.D.); (D.A.); (A.M.); (A.P.); (M.N.); (J.H.); (B.G.)
| | - Alina Phen
- Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1G6, Canada; (A.L.D.); (D.A.); (A.M.); (A.P.); (M.N.); (J.H.); (B.G.)
| | - Mehrnoosh Neshatian
- Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1G6, Canada; (A.L.D.); (D.A.); (A.M.); (A.P.); (M.N.); (J.H.); (B.G.)
| | - James Holcroft
- Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1G6, Canada; (A.L.D.); (D.A.); (A.M.); (A.P.); (M.N.); (J.H.); (B.G.)
| | - Johan Bonde
- Division of Pure and Applied Biochemistry, Center of Applied Life Sciences, Lund University, 223 62 Lund, Sweden;
| | - Bernhard Ganss
- Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1G6, Canada; (A.L.D.); (D.A.); (A.M.); (A.P.); (M.N.); (J.H.); (B.G.)
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
| | - Karina M. M. Carneiro
- Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1G6, Canada; (A.L.D.); (D.A.); (A.M.); (A.P.); (M.N.); (J.H.); (B.G.)
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
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7
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Cell-Free Biomimetic Mineralization Strategies to Regenerate the Enamel Microstructure. CRYSTALS 2021. [DOI: 10.3390/cryst11111385] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The distinct architecture of native enamel gives it its exquisite appearance and excellent intrinsic-extrinsic fracture toughening properties. However, damage to the enamel is irreversible. At present, the clinical treatment for enamel lesion is an invasive method; besides, its limitations, caused by the chemical and physical difference between restorative materials and dental hard tissue, makes the restorative effects far from ideal. With more investigations on the mechanism of amelogenesis, biomimetic mineralization techniques for enamel regeneration have been well developed, which hold great promise as a non-invasive strategy for enamel restoration. This review disclosed the chemical and physical mechanism of amelogenesis; meanwhile, it overviewed and summarized studies involving the regeneration of enamel microstructure in cell-free biomineralization approaches, which could bring new prospects for resolving the challenges in enamel regeneration.
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8
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Juanes-Gusano D, Santos M, Reboto V, Alonso M, Rodríguez-Cabello JC. Self-assembling systems comprising intrinsically disordered protein polymers like elastin-like recombinamers. J Pept Sci 2021; 28:e3362. [PMID: 34545666 DOI: 10.1002/psc.3362] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 07/02/2021] [Accepted: 07/13/2021] [Indexed: 12/19/2022]
Abstract
Despite lacking cooperatively folded structures under native conditions, numerous intrinsically disordered proteins (IDPs) nevertheless have great functional importance. These IDPs are hybrids containing both ordered and intrinsically disordered protein regions (IDPRs), the structure of which is highly flexible in this unfolded state. The conformational flexibility of these disordered systems favors transitions between disordered and ordered states triggered by intrinsic and extrinsic factors, folding into different dynamic molecular assemblies to enable proper protein functions. Indeed, prokaryotic enzymes present less disorder than eukaryotic enzymes, thus showing that this disorder is related to functional and structural complexity. Protein-based polymers that mimic these IDPs include the so-called elastin-like polypeptides (ELPs), which are inspired by the composition of natural elastin. Elastin-like recombinamers (ELRs) are ELPs produced using recombinant techniques and which can therefore be tailored for a specific application. One of the most widely used and studied characteristic structures in this field is the pentapeptide (VPGXG)n . The structural disorder in ELRs probably arises due to the high content of proline and glycine in the ELR backbone, because both these amino acids help to keep the polypeptide structure of elastomers disordered and hydrated. Moreover, the recombinant nature of these systems means that different sequences can be designed, including bioactive domains, to obtain specific structures for each application. Some of these structures, along with their applications as IDPs that self-assemble into functional vesicles or micelles from diblock copolymer ELRs, will be studied in the following sections. The incorporation of additional order- and disorder-promoting peptide/protein domains, such as α-helical coils or β-strands, in the ELR sequence, and their influence on self-assembly, will also be reviewed. In addition, chemically cross-linked systems with controllable order-disorder balance, and their role in biomineralization, will be discussed. Finally, we will review different multivalent IDPs-based coatings and films for different biomedical applications, such as spatially controlled cell adhesion, osseointegration, or biomaterial-associated infection (BAI).
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Affiliation(s)
- Diana Juanes-Gusano
- BIOFORGE (Group for Advanced Materials and Nanobiotechnology) CIBER-BBN, Edificio Lucía, University of Valladolid, Valladolid, Spain
| | - Mercedes Santos
- BIOFORGE (Group for Advanced Materials and Nanobiotechnology) CIBER-BBN, Edificio Lucía, University of Valladolid, Valladolid, Spain
| | - Virginia Reboto
- BIOFORGE (Group for Advanced Materials and Nanobiotechnology) CIBER-BBN, Edificio Lucía, University of Valladolid, Valladolid, Spain
| | - Matilde Alonso
- BIOFORGE (Group for Advanced Materials and Nanobiotechnology) CIBER-BBN, Edificio Lucía, University of Valladolid, Valladolid, Spain
| | - José Carlos Rodríguez-Cabello
- BIOFORGE (Group for Advanced Materials and Nanobiotechnology) CIBER-BBN, Edificio Lucía, University of Valladolid, Valladolid, Spain
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9
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Radvar E, Griffanti G, Tsolaki E, Bertazzo S, Nazhat SN, Addison O, Mata A, Shanahan CM, Elsharkawy S. Engineered In vitro Models for Pathological Calcification: Routes Toward Mechanistic Understanding. ADVANCED NANOBIOMED RESEARCH 2021. [DOI: 10.1002/anbr.202100042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Elham Radvar
- Centre for Oral, Clinical and Translational Sciences Faculty of Dentistry, Oral and Craniofacial Sciences King's College London London SE1 1UL UK
| | - Gabriele Griffanti
- Department of Mining and Materials Engineering Faculty of Engineering McGill University Montreal QC H3A 0C5 Canada
| | - Elena Tsolaki
- Department of Medical Physics and Biomedical Engineering University College London London WC1E 6BT UK
| | - Sergio Bertazzo
- Department of Medical Physics and Biomedical Engineering University College London London WC1E 6BT UK
| | - Showan N. Nazhat
- Department of Mining and Materials Engineering Faculty of Engineering McGill University Montreal QC H3A 0C5 Canada
| | - Owen Addison
- Centre for Oral, Clinical and Translational Sciences Faculty of Dentistry, Oral and Craniofacial Sciences King's College London London SE1 1UL UK
| | - Alvaro Mata
- School of Pharmacy University of Nottingham Nottingham NG7 2RD UK
| | - Catherine M. Shanahan
- BHF Centre of Research Excellence Cardiovascular Division James Black Centre King's College London London SE1 1UL UK
| | - Sherif Elsharkawy
- Centre for Oral, Clinical and Translational Sciences Faculty of Dentistry, Oral and Craniofacial Sciences King's College London London SE1 1UL UK
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10
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Fang Z, Guo M, Zhou Q, Li Q, Wong HM, Cao CY. Enamel-like tissue regeneration by using biomimetic enamel matrix proteins. Int J Biol Macromol 2021; 183:2131-2141. [PMID: 34111481 DOI: 10.1016/j.ijbiomac.2021.06.028] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 06/04/2021] [Accepted: 06/04/2021] [Indexed: 01/15/2023]
Abstract
Enamel regeneration currently -is limited by our inability to duplicate artificially its complicated and well-aligned hydroxyapatite structure. The initial formation of enamel occurs in enamel organs where the ameloblasts secret enamel extracellular matrix formed a unique gel-like microenvironment. The enamel extracellular matrix is mainly composed by amelogenin and non-amelogenin. In this study, an innovative strategy was proposed to regenerate enamel-like tissue by constructing a microenvironment using biomimetic enamel matrix proteins (biomimetic EMPs) composed of modified leucine-rich amelogenin peptide (mLRAP) and non-amelogenin analog (NAA). Impressively, the regenerated enamel in this biomimetic EMPs on etched enamel surface produced prismatic structures, and showed similar mechanical properties to natural enamel. The results of X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) showed that regenerated crystal was hydroxyapatite. Molecular dynamics simulation analysis showed the binding energy between mLRAP and NAA were electrostatic forces and Van der Walls. These results introduced a promising strategy to induce crystal growth of enamel-like hydroxyapatite for biomimetic reproduction of materials with complicated hierarchical microstructures.
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Affiliation(s)
- Zehui Fang
- Stomatologic Hospital & College, Anhui Medical University, Key Lab.of Oral Diseases Research of Anhui Province, Hefei, 230032, China
| | - Mengxi Guo
- Stomatologic Hospital & College, Anhui Medical University, Key Lab.of Oral Diseases Research of Anhui Province, Hefei, 230032, China
| | - Qingli Zhou
- Stomatologic Hospital & College, Anhui Medical University, Key Lab.of Oral Diseases Research of Anhui Province, Hefei, 230032, China
| | - Quanli Li
- Stomatologic Hospital & College, Anhui Medical University, Key Lab.of Oral Diseases Research of Anhui Province, Hefei, 230032, China
| | - Hai Ming Wong
- Paediatric Dentistry and Orthodontics, Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Hong Kong
| | - Chris Ying Cao
- Stomatologic Hospital & College, Anhui Medical University, Key Lab.of Oral Diseases Research of Anhui Province, Hefei, 230032, China.
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11
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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.
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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.
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12
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Shaw WJ, Tarasevich BJ, Buchko GW, Arachchige RMJ, Burton SD. Controls of nature: Secondary, tertiary, and quaternary structure of the enamel protein amelogenin in solution and on hydroxyapatite. J Struct Biol 2020; 212:107630. [PMID: 32979496 PMCID: PMC7744360 DOI: 10.1016/j.jsb.2020.107630] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 09/12/2020] [Accepted: 09/17/2020] [Indexed: 10/23/2022]
Abstract
Amelogenin, a protein critical to enamel formation, is presented as a model for understanding how the structure of biomineralization proteins orchestrate biomineral formation. Amelogenin is the predominant biomineralization protein in the early stages of enamel formation and contributes to the controlled formation of hydroxyapatite (HAP) enamel crystals. The resulting enamel mineral is one of the hardest tissues in the human body and one of the hardest biominerals in nature. Structural studies have been hindered by the lack of techniques to evaluate surface adsorbed proteins and by amelogenin's disposition to self-assemble. Recent advancements in solution and solid state nuclear magnetic resonance (NMR) spectroscopy, atomic force microscopy (AFM), and recombinant isotope labeling strategies are now enabling detailed structural studies. These recent studies, coupled with insights from techniques such as CD and IR spectroscopy and computational methodologies, are contributing to important advancements in our structural understanding of amelogenesis. In this review we focus on recent advances in solution and solid state NMR spectroscopy and in situ AFM that reveal new insights into the secondary, tertiary, and quaternary structure of amelogenin by itself and in contact with HAP. These studies have increased our understanding of the interface between amelogenin and HAP and how amelogenin controls enamel formation.
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Affiliation(s)
- Wendy J Shaw
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
| | - Barbara J Tarasevich
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Garry W Buchko
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99352, USA; School of Molecular Bioscience, Washington State University, Pullman, WA 99164, USA
| | - Rajith M J Arachchige
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Sarah D Burton
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99352, USA
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13
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Fischer NG, Münchow EA, Tamerler C, Bottino MC, Aparicio C. Harnessing biomolecules for bioinspired dental biomaterials. J Mater Chem B 2020; 8:8713-8747. [PMID: 32747882 PMCID: PMC7544669 DOI: 10.1039/d0tb01456g] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Dental clinicians have relied for centuries on traditional dental materials (polymers, ceramics, metals, and composites) to restore oral health and function to patients. Clinical outcomes for many crucial dental therapies remain poor despite many decades of intense research on these materials. Recent attention has been paid to biomolecules as a chassis for engineered preventive, restorative, and regenerative approaches in dentistry. Indeed, biomolecules represent a uniquely versatile and precise tool to enable the design and development of bioinspired multifunctional dental materials to spur advancements in dentistry. In this review, we survey the range of biomolecules that have been used across dental biomaterials. Our particular focus is on the key biological activity imparted by each biomolecule toward prevention of dental and oral diseases as well as restoration of oral health. Additional emphasis is placed on the structure-function relationships between biomolecules and their biological activity, the unique challenges of each clinical condition, limitations of conventional therapies, and the advantages of each class of biomolecule for said challenge. Biomaterials for bone regeneration are not reviewed as numerous existing reviews on the topic have been recently published. We conclude our narrative review with an outlook on the future of biomolecules in dental biomaterials and potential avenues of innovation for biomaterial-based patient oral care.
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Affiliation(s)
- Nicholas G Fischer
- Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota, 16-250A Moos Tower, 515 Delaware St. SE, Minneapolis, Minnesota 55455, USA.
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14
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Wang D, Deng J, Deng X, Fang C, Zhang X, Yang P. Controlling Enamel Remineralization by Amyloid-Like Amelogenin Mimics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2002080. [PMID: 32583928 DOI: 10.1002/adma.202002080] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/16/2020] [Indexed: 06/11/2023]
Abstract
In situ regeneration of the enamel-like structure of hydroxyapatite (HAp) crystals under oral conditions is significant for dental caries treatment. However, it is still a challenge for dentists to duplicate the elegant and well-aligned apatite structure bonding to the surface of demineralized enamel. A biocompatible amelogenin-inspired matrix, a phase-transited lysozyme (PTL) film mimicking an N-terminal amelogenin with central domain (N-Ame) combined with synthetic peptide (C-AMG) based on the functional domains of C-terminal telopeptide (C-Ame) is shown here, which is formed by amyloid-like lysozyme aggregation at the enamel interface through a rapid one-step aqueous coating process. In the PTL/C-AMG matrix, C-AMG facilitated the oriented arrangement of amorphous calcium phosphate (ACP) nanoparticles and their transformation to ordered enamel-like HAp crystals, while PTL served as a strong interfacial anchor to immobilize the C-AMG peptide and PTL/C-AMG matrix on versatile substrate surfaces. PTL/C-AMG film-coated enamel induced both of the in vivo and in vitro synthesis of HAp crystals, facilitated epitaxial growth of HAp crystals and recovered the highly oriented structure and mechanical properties to levels nearly identical to those of natural enamel. This work underlines the importance of amyloid-like protein aggregates in the biomineralization of enamel, providing a promising strategy for treating dental caries.
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Affiliation(s)
- Dong Wang
- School of Mechanical and Precision Instrument Engineering, Xi'an University of Technology, Xi'an, 710048, China
| | - Jingjing Deng
- School and Hospital of Stomatology, Tianjin Medical University, 12 Observatory Road, Tianjin, 30070, China
| | - Xuliang Deng
- Department of Geriatric Dentistry, School and Hospital of Stomatology, Peking University, 22 Zhongguancun South Street, Beijing, 100081, China
| | - Changqing Fang
- School of Mechanical and Precision Instrument Engineering, Xi'an University of Technology, Xi'an, 710048, China
- The Faculty of Printing, Packaging Engineering and Digital Media Technology, Xi'an University of Technology, Xi'an, 710048, China
| | - Xu Zhang
- School and Hospital of Stomatology, Tianjin Medical University, 12 Observatory Road, Tianjin, 30070, China
| | - Peng Yang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China
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15
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Wijedasa NP, Broas SM, Daso RE, Banerjee IA. Varying fish scale derived hydroxyapatite bound hybrid peptide nanofiber scaffolds for potential applications in periodontal tissue regeneration. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2020; 109:110540. [DOI: 10.1016/j.msec.2019.110540] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 12/09/2019] [Accepted: 12/10/2019] [Indexed: 01/30/2023]
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16
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Affiliation(s)
- Rein V. Ulijn
- Advanced Science Research Center (ASRC) at the Graduate Center City University of New York (CUNY) 10017 New York, NY, USA
- Department of Chemistry Hunter College, CUNY 10065 New York, NY USA
- Biochemistry and Chemistry Ph.D. Programs The Graduate Center of the CUNY 10016 New York, NY USA
| | - Ayala Lampel
- School of Molecular Cell Biology and Biotechnology Tel Aviv University 6997801 Tel Aviv Israel
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17
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Ibáñez-Fonseca A, Flora T, Acosta S, Rodríguez-Cabello JC. Trends in the design and use of elastin-like recombinamers as biomaterials. Matrix Biol 2019; 84:111-126. [PMID: 31288085 DOI: 10.1016/j.matbio.2019.07.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 06/23/2019] [Accepted: 07/05/2019] [Indexed: 12/16/2022]
Abstract
Elastin-like recombinamers (ELRs), which derive from one of the repetitive domains found in natural elastin, have been intensively studied in the last few years from several points of view. In this mini review, we discuss all the recent works related to the investigation of ELRs, starting with those that define these polypeptides as model intrinsically disordered proteins or regions (IDPs or IDRs) and its relevance for some biomedical applications. Furthermore, we summarize the current knowledge on the development of drug, vaccine and gene delivery systems based on ELRs, while also emphasizing the use of ELR-based hydrogels in tissue engineering and regenerative medicine (TERM). Finally, we show different studies that explore applications in other fields, and several examples that describe biomaterial blends in which ELRs have a key role. This review aims to give an overview of the recent advances regarding ELRs and to encourage further investigation of their properties and applications.
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Affiliation(s)
- Arturo Ibáñez-Fonseca
- BIOFORGE Lab, CIBER-BBN, University of Valladolid, Paseo de Belén 19, 47011 Valladolid, Spain
| | - Tatjana Flora
- BIOFORGE Lab, CIBER-BBN, University of Valladolid, Paseo de Belén 19, 47011 Valladolid, Spain
| | - Sergio Acosta
- BIOFORGE Lab, CIBER-BBN, University of Valladolid, Paseo de Belén 19, 47011 Valladolid, Spain
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18
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Shlaferman J, Paige A, Meserve K, Miech JA, Gerdon AE. Selected DNA Aptamers Influence Kinetics and Morphology in Calcium Phosphate Mineralization. ACS Biomater Sci Eng 2019; 5:3228-3236. [DOI: 10.1021/acsbiomaterials.9b00308] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Jacob Shlaferman
- Department of Chemistry and Physics, Emmanuel College, 400 The Fenway, Boston, Massachusetts 02115, United States
| | - Alexander Paige
- Department of Chemistry and Physics, Emmanuel College, 400 The Fenway, Boston, Massachusetts 02115, United States
| | - Krista Meserve
- Department of Chemistry and Physics, Emmanuel College, 400 The Fenway, Boston, Massachusetts 02115, United States
| | - Jason A. Miech
- Department of Chemistry and Physics, Emmanuel College, 400 The Fenway, Boston, Massachusetts 02115, United States
| | - Aren E. Gerdon
- Department of Chemistry and Physics, Emmanuel College, 400 The Fenway, Boston, Massachusetts 02115, United States
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19
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Mechanics of amelogenin TRAP protein in the proximity of hydroxyapatite mineral is altered by interfacial water. Chem Phys 2019. [DOI: 10.1016/j.chemphys.2019.02.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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20
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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.
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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
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21
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Elsharkawy S, Mata A. Hierarchical Biomineralization: from Nature's Designs to Synthetic Materials for Regenerative Medicine and Dentistry. Adv Healthc Mater 2018; 7:e1800178. [PMID: 29943412 DOI: 10.1002/adhm.201800178] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 04/08/2018] [Indexed: 12/28/2022]
Abstract
Biomineralization is a highly dynamic, yet controlled, process that many living creatures employ to develop functional tissues such as tooth enamel, bone, and others. A major goal in materials science is to create bioinspired functional structures based on the precise organization of building blocks across multiple length scales. Therefore, learning how nature has evolved to use biomineralization could inspire new ways to design and develop synthetic hierarchical materials with enhanced functionality. Toward this goal, this review dissects the current understanding of structure-function relationships of dental enamel and bone using a materials science perspective and discusses a wide range of synthetic technologies that aim to recreate their hierarchical organization and functionality. Insights into how these strategies could be applied for regenerative medicine and dentistry are also provided.
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Affiliation(s)
- Sherif Elsharkawy
- Institute of Bioengineering; Queen Mary University of London; London E1 4NS UK
- School of Engineering and Materials Science; Queen Mary University of London; London E1 4NS UK
- Institute of Dentistry; Barts and The London School of Medicine and Dentistry; Queen Mary University of London; London E1 4NS UK
| | - Alvaro Mata
- Institute of Bioengineering; Queen Mary University of London; London E1 4NS UK
- School of Engineering and Materials Science; Queen Mary University of London; London E1 4NS UK
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22
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Protein disorder–order interplay to guide the growth of hierarchical mineralized structures. Nat Commun 2018; 9:2145. [PMID: 29858566 PMCID: PMC5984621 DOI: 10.1038/s41467-018-04319-0] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 04/18/2018] [Indexed: 01/05/2023] Open
Abstract
A major goal in materials science is to develop bioinspired functional materials based on the precise control of molecular building blocks across length scales. Here we report a protein-mediated mineralization process that takes advantage of disorder–order interplay using elastin-like recombinamers to program organic–inorganic interactions into hierarchically ordered mineralized structures. The materials comprise elongated apatite nanocrystals that are aligned and organized into microscopic prisms, which grow together into spherulite-like structures hundreds of micrometers in diameter that come together to fill macroscopic areas. The structures can be grown over large uneven surfaces and native tissues as acid-resistant membranes or coatings with tuneable hierarchy, stiffness, and hardness. Our study represents a potential strategy for complex materials design that may open opportunities for hard tissue repair and provide insights into the role of molecular disorder in human physiology and pathology. There is evidence that disordered proteins play a role in the mineralization process. Here, the authors report on the development of elastin-like recombinant protein membranes using disordered-ordered interplay to investigate and guide mineralization.
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23
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Abstract
Gluten‐related disorders are a complex group of diseases that involve the activation of the immune system triggered by the ingestion of gluten. Among these, celiac disease, with a prevalence of 1 %, is the most investigated, but recently, a new pathology, named nonceliac gluten sensitivity, was reported with a general prevalence of 7 %. Finally, there other less‐prevalent gluten‐related diseases such as wheat allergy, gluten ataxia, and dermatitis herpetiformis (with an overall prevalence of less than 0.1 %). As mentioned, the common molecular trigger is gluten, a complex mixture of storage proteins present in wheat, barley, and a variety of oats that are not fully degraded by humans. The most‐studied protein related to disease is gliadin, present in wheat, which possesses in its sequence many pathological fragments. Despite a lot of effort to treat these disorders, the only effective method is a long‐life gluten‐free diet. This Review summarizes the actual knowledge of gluten‐related disorders from a translational chemistry point of view. We discuss what is currently known from the literature about the interaction of gluten with the gut and the critical host responses it evokes and, finally, connect them to our current and novel molecular understanding of the supramolecular organization of gliadin and the 33‐mer gliadin peptide fragment under physiological conditions.
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Affiliation(s)
- Karen M Lammers
- Laboratory Immunogenetics, Department of Medical Microbiology and Infection Control VU University Medical Center 1081 Amsterdam Netherlands
| | - Maria G Herrera
- Faculty of Pharmacy and Biochemistry Institute of biological chemistry and Physicochemical CONICET-University of Buenos Aires Junín 956 C1113AAD Buenos Aires Argentina
| | - Veronica I Dodero
- Department of Chemistry, Organic Chemistry III Bielefeld University Universitätsstraße 25 33615 Bielefeld Germany
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24
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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.
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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
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25
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Lacruz RS. Enamel: Molecular identity of its transepithelial ion transport system. Cell Calcium 2017; 65:1-7. [PMID: 28389033 PMCID: PMC5944837 DOI: 10.1016/j.ceca.2017.03.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 03/27/2017] [Accepted: 03/27/2017] [Indexed: 12/14/2022]
Abstract
Enamel is the most calcified tissue in vertebrates. It differs from bone in a number of characteristics including its origin from ectodermal epithelium, lack of remodeling capacity by the enamel forming cells, and absence of collagen. The enamel-forming cells known as ameloblasts, choreograph first the synthesis of a unique protein-rich matrix, followed by the mineralization of this matrix into a tissue that is ∼95% mineral. To do this, ameloblasts arrange the coordinated movement of ions across a cell barrier while removing matrix proteins and monitoring extracellular pH using a variety of buffering systems to enable the growth of carbonated apatite crystals. Although our knowledge of these processes and the molecular identity of the proteins involved in transepithelial ion transport has increased in the last decade, it remains limited compared to other cells. Here we present an overview of the evolution and development of enamel, its differences with bone, and describe the ion transport systems associated with ameloblasts.
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Affiliation(s)
- Rodrigo S Lacruz
- Dept. Basic Science and Craniofacial Biology, New York University College of Dentistry, 345 East 24th Street, New York, NY 10010, United States.
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26
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Yamazaki H, Beniash E, Yamakoshi Y, Simmer JP, Margolis HC. Protein Phosphorylation and Mineral Binding Affect the Secondary Structure of the Leucine-Rich Amelogenin Peptide. Front Physiol 2017; 8:450. [PMID: 28706493 PMCID: PMC5489624 DOI: 10.3389/fphys.2017.00450] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 06/14/2017] [Indexed: 12/31/2022] Open
Abstract
Previously, we have shown that serine-16 phosphorylation in native full-length porcine amelogenin (P173) and the Leucine-Rich Amelogenin Peptide (LRAP(+P)), an alternative amelogenin splice product, affects protein assembly and mineralization in vitro. Notably, P173 and LRAP(+P) stabilize amorphous calcium phosphate (ACP) and inhibit hydroxyapatite (HA) formation, while non-phosphorylated counterparts (rP172, LRAP(-P)) guide the growth of ordered bundles of HA crystals. Based on these findings, we hypothesize that the phosphorylation of full-length amelogenin and LRAP induces conformational changes that critically affect its capacity to interact with forming calcium phosphate mineral phases. To test this hypothesis, we have utilized Fourier transform infrared spectroscopy (FTIR) to determine the secondary structure of LRAP(-P) and LRAP(+P) in the absence/presence of calcium and selected mineral phases relevant to amelogenesis; i.e., hydroxyapatite (HA: an enamel crystal prototype) and (ACP: an enamel crystal precursor phase). Aqueous solutions of LRAP(-P) or LRAP(+P) were prepared with or without 7.5 mM of CaCl2 at pH 7.4. FTIR spectra of each solution were obtained using attenuated total reflectance, and amide-I peaks were analyzed to provide secondary structure information. Secondary structures of LRAP(+P) and LRAP(-P) were similarly assessed following incubation with suspensions of HA and pyrophosphate-stabilized ACP. Amide I spectra of LRAP(-P) and LRAP(+P) were found to be distinct from each other in all cases. Spectra analyses showed that LRAP(-P) is comprised mostly of random coil and β-sheet, while LRAP(+P) exhibits more β-sheet and α-helix with little random coil. With added Ca, the random coil content increased in LRAP(-P), while LRAP(+P) exhibited a decrease in α-helix components. Incubation of LRAP(-P) with HA or ACP resulted in comparable increases in β-sheet structure. Notably, however, LRAP(+P) secondary structure was more affected by ACP, primarily showing an increase in β-sheet structure, compared to that observed with added HA. These collective findings indicate that phosphorylation induces unique secondary structural changes that may enhance the functional capacity of native phosphorylated amelogenins like LRAP to stabilize an ACP precursor phase during early stages of enamel mineral formation.
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Affiliation(s)
- Hajime Yamazaki
- Center for Biomineralization, The Forsyth InstituteCambridge, MA, United States.,Department of Developmental Biology, Harvard School of Dental MedicineBoston, MA, United States
| | - Elia Beniash
- Department of Oral Biology, Center for Craniofacial Regeneration, McGowan Institute for Regenerative Medicine, University of PittsburghPittsburgh, PA, United States
| | - Yasuo Yamakoshi
- Department of Biochemistry and Molecular Biology, School of Dental Medicine, Tsurumi UniversityYokohama, Japan
| | - James P Simmer
- Department of Biologic and Materials Sciences, University of Michigan School of DentistryAnn Arbor, MI, United States
| | - Henry C Margolis
- Center for Biomineralization, The Forsyth InstituteCambridge, MA, United States.,Department of Developmental Biology, Harvard School of Dental MedicineBoston, MA, United States
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27
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Albumin conformational change and aggregation induced by nanostructured apatites. Biointerphases 2017; 12:02D403. [DOI: 10.1116/1.4982641] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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28
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Connelly C, Cicuto T, Leavitt J, Petty A, Litman A, Margolis HC, Gerdon AE. Dynamic interactions of amelogenin with hydroxyapatite surfaces are dependent on protein phosphorylation and solution pH. Colloids Surf B Biointerfaces 2016; 148:377-384. [PMID: 27632699 DOI: 10.1016/j.colsurfb.2016.09.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 08/03/2016] [Accepted: 09/07/2016] [Indexed: 10/21/2022]
Abstract
Amelogenin, the predominant extracellular matrix protein secreted by ameloblasts, has been shown to be essential for proper tooth enamel formation. In this study, amelogenin adsorption to hydroxyapatite (HAP) surfaces, a prototype for enamel mineral, has been studied using a quartz crystal microbalance (QCM) to interrogate effects of protein phosphorylation and solution pH. Dynamic flow-based experiments were conducted at pH 7.4 and 8.0 using native phosphorylated porcine amelogenin (P173) and recombinant non-phosphorylated porcine amelogenin (rP172). Loading capacities (μmol/m2) on HAP surfaces were calculated under all conditions and adsorption affinities (Kad) were calculated when Langmuir isotherm conditions appeared to be met. At pH 8.0, binding characteristics were remarkably similar for the two proteins. However, at pH 7.4 a higher affinity and lower surface loading for the phosphorylated P173 was found compared to any other set of conditions. This suggests that phosphorylated P173 adopts a more extended conformation than non-phosphorylated full-length amelogenin, occupying a larger footprint on the HAP surface. This surface-induced structural difference may help explain why P173 is a more effective inhibitor of spontaneous HAP formation in vitro than rP172. Differences in the viscoelastic properties of P173 and rP172 in the adsorbed state were also observed, consistent with noted differences in HAP binding. These collective findings provide new insight into the important role of amelogenin phosphorylation in the mechanism by which amelogenin regulates enamel crystal formation.
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Affiliation(s)
| | - Thomas Cicuto
- Emmanuel College, Department of Chemistry and Physics, Boston, MA 02115, USA
| | - Jason Leavitt
- Emmanuel College, Department of Chemistry and Physics, Boston, MA 02115, USA
| | - Alexander Petty
- Emmanuel College, Department of Chemistry and Physics, Boston, MA 02115, USA
| | - Amy Litman
- The Forsyth Institute, Center for Biomineralization, Department of Applied Oral Sciences, Cambridge, MA 02142, USA
| | - Henry C Margolis
- The Forsyth Institute, Center for Biomineralization, Department of Applied Oral Sciences, Cambridge, MA 02142, USA
| | - Aren E Gerdon
- Emmanuel College, Department of Chemistry and Physics, Boston, MA 02115, USA.
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29
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Apicella A, Marascio M, Colangelo V, Soncini M, Gautieri A, Plummer CJG. Molecular dynamics simulations of the intrinsically disordered protein amelogenin. J Biomol Struct Dyn 2016; 35:1813-1823. [PMID: 27366858 DOI: 10.1080/07391102.2016.1196151] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Amelogenin refers to a class of intrinsically disordered proteins that are the major constituents of enamel matrix derivative (EMD), an extract of porcine fetal teeth used in regenerative periodontal therapy. Modifications in molecular conformation induced by external stresses, such as changes in temperature or pH, are known to reduce the effectiveness of EMD. However, detailed descriptions of the conformational behavior of native amelogenin are lacking in the open literature. In the present work, a molecular model for the secondary and tertiary structure of the full-length major porcine amelogenin P173 was constructed from its primary sequence by replica exchange molecular dynamics (REMD) simulations. The REMD results for isolated amelogenin molecules at different temperatures were shown to be consistent with the available spectroscopic data. They therefore represent an important first step toward the simulation of the intra- and intermolecular interactions that mediate self-organization in amelogenin and its behavior in the presence of other EMD components under conditions representative of its therapeutic application.
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Affiliation(s)
- Alessandra Apicella
- a Laboratoire de Technologie des Composites et Polymères (LTC) , Ecole Polytechnique Fédérale de Lausanne (EPFL) , Station 12, CH-1015 Lausanne , Switzerland
| | - Matteo Marascio
- a Laboratoire de Technologie des Composites et Polymères (LTC) , Ecole Polytechnique Fédérale de Lausanne (EPFL) , Station 12, CH-1015 Lausanne , Switzerland.,b Dipartimento di Elettronica, Informazione e Bioingegneria , Politecnico di Milano , Piazza Leonardo da Vinci 32, 20133 Milan , Italy
| | - Vincenzo Colangelo
- b Dipartimento di Elettronica, Informazione e Bioingegneria , Politecnico di Milano , Piazza Leonardo da Vinci 32, 20133 Milan , Italy
| | - Monica Soncini
- b Dipartimento di Elettronica, Informazione e Bioingegneria , Politecnico di Milano , Piazza Leonardo da Vinci 32, 20133 Milan , Italy
| | - Alfonso Gautieri
- b Dipartimento di Elettronica, Informazione e Bioingegneria , Politecnico di Milano , Piazza Leonardo da Vinci 32, 20133 Milan , Italy
| | - Christopher J G Plummer
- a Laboratoire de Technologie des Composites et Polymères (LTC) , Ecole Polytechnique Fédérale de Lausanne (EPFL) , Station 12, CH-1015 Lausanne , Switzerland
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30
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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.
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Affiliation(s)
- Adele L Boskey
- Musculoskeletal Integrity Program, Hospital for Special Surgery, New York, NY 10021, USA.
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31
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Apicella A, Heunemann P, Bolisetty S, Marascio M, Gemperli Graf A, Garamszegi L, Mezzenga R, Fischer P, Plummer CJ, Månson JA. The Influence of Arginine on the Response of Enamel Matrix Derivative (EMD) Proteins to Thermal Stress: Towards Improving the Stability of EMD-Based Products. PLoS One 2015; 10:e0144641. [PMID: 26670810 PMCID: PMC4699454 DOI: 10.1371/journal.pone.0144641] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 10/07/2015] [Indexed: 11/19/2022] Open
Abstract
In a current procedure for periodontal tissue regeneration, enamel matrix derivative (EMD), which is the active component, is mixed with a propylene glycol alginate (PGA) gel carrier and applied directly to the periodontal defect. Exposure of EMD to physiological conditions then causes it to precipitate. However, environmental changes during manufacture and storage may result in modifications to the conformation of the EMD proteins, and eventually premature phase separation of the gel and a loss in therapeutic effectiveness. The present work relates to efforts to improve the stability of EMD-based formulations such as Emdogain™ through the incorporation of arginine, a well-known protein stabilizer, but one that to our knowledge has not so far been considered for this purpose. Representative EMD-buffer solutions with and without arginine were analyzed by 3D-dynamic light scattering, UV-Vis spectroscopy, transmission electron microscopy and Fourier transform infrared spectroscopy at different acidic pH and temperatures, T, in order to simulate the effect of pH variations and thermal stress during manufacture and storage. The results provided evidence that arginine may indeed stabilize EMD against irreversible aggregation with respect to variations in pH and T under these conditions. Moreover, stopped-flow transmittance measurements indicated arginine addition not to suppress precipitation of EMD from either the buffers or the PGA gel carrier when the pH was raised to 7, a fundamental requirement for dental applications.
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Affiliation(s)
- Alessandra Apicella
- Laboratoire des Technologie des Composites et Polymères (LTC), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Peggy Heunemann
- Food Process Engineering, Institute of Food, Nutrition and Health, ETH Zurich, 8092 Zurich, Switzerland
| | - Sreenath Bolisetty
- Food and Soft Materials Science, Institute of Food, Nutrition and Health, ETH Zurich, 8092 Zurich, Switzerland
| | - Matteo Marascio
- Laboratoire des Technologie des Composites et Polymères (LTC), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | | | | | - Raffaele Mezzenga
- Food and Soft Materials Science, Institute of Food, Nutrition and Health, ETH Zurich, 8092 Zurich, Switzerland
| | - Peter Fischer
- Food Process Engineering, Institute of Food, Nutrition and Health, ETH Zurich, 8092 Zurich, Switzerland
- * E-mail: (PF); (CJP)
| | - Christopher J. Plummer
- Laboratoire des Technologie des Composites et Polymères (LTC), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
- * E-mail: (PF); (CJP)
| | - Jan-Anders Månson
- Laboratoire des Technologie des Composites et Polymères (LTC), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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Abstract
Mature tooth enamel is acellular and does not regenerate itself. Developing technologies that rebuild tooth enamel and preserve tooth structure is therefore of great interest. Considering the importance of amelogenin protein in dental enamel formation, its ability to control apatite mineralization in vitro, and its potential to be applied in fabrication of future bio-inspired dental material this review focuses on two major subjects: amelogenin and enamel biomimetics. We review the most recent findings on amelogenin secondary and tertiary structural properties with a focus on its interactions with different targets including other enamel proteins, apatite mineral, and phospholipids. Following a brief overview of enamel hierarchical structure and its mechanical properties we will present the state-of-the-art strategies in the biomimetic reconstruction of human enamel.
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Affiliation(s)
- Qichao Ruan
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, USA
| | - Janet Moradian-Oldak
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, USA
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Lokappa SB, Chandrababu KB, Dutta K, Perovic I, Evans JS, Moradian-Oldak J. Interactions of amelogenin with phospholipids. Biopolymers 2015; 103:96-108. [PMID: 25298002 PMCID: PMC4415992 DOI: 10.1002/bip.22573] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 08/29/2014] [Accepted: 10/02/2014] [Indexed: 11/08/2022]
Abstract
Amelogenin protein has the potential to interact with other enamel matrix proteins, mineral, and cell surfaces. We investigated the interactions of recombinant amelogenin rP172 with small unilamellar vesicles as model membranes, toward the goal of understanding the mechanisms of amelogenin-cell interactions during amelogenesis. Dynamic light scattering (DLS), fluorescence spectroscopy, circular dichroism (CD), and nuclear magnetic resonance (NMR) were used. In the presence of phospholipid vesicles, a blue shift in the Trp fluorescence emission maxima of rP172 was observed (∼334 nm) and the Trp residues of rP172 were inaccessible to the aqueous quencher acrylamide. DLS studies indicated complexation of rP172 and phospholipids, although the possibility of fusion of phospholipids following amelogenin addition cannot be ruled out. NMR and CD studies revealed a disorder-order transition of rP172 in a model membrane environment. Strong fluorescence resonance energy transfer from Trp in rP172 to DNS-bound-phospholipid was observed, and fluorescence polarization studies indicated that rP172 interacted with the hydrophobic core region of model membranes. Our data suggest that amelogenin has ability to interact with phospholipids and that such interactions may play key roles in enamel biomineralization as well as reported amelogenin signaling activities.
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Affiliation(s)
- Sowmya Bekshe Lokappa
- Center for Craniofacial Molecular Biology, University of Southern California, School of Dentistry, Los Angeles, California 90033
| | - Karthik Balakrishna Chandrababu
- Center for Craniofacial Molecular Biology, University of Southern California, School of Dentistry, Los Angeles, California 90033
| | - Kaushik Dutta
- Laboratory for Chemical Physics, Division of Basic Sciences and Craniofacial Biology, New York University, New York, New York 10010
| | - Iva Perovic
- Laboratory for Chemical Physics, Division of Basic Sciences and Craniofacial Biology, New York University, New York, New York 10010
| | - John Spencer Evans
- Laboratory for Chemical Physics, Division of Basic Sciences and Craniofacial Biology, New York University, New York, New York 10010
| | - Janet Moradian-Oldak
- Center for Craniofacial Molecular Biology, University of Southern California, School of Dentistry, Los Angeles, California 90033
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34
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Ruan Q, Moradian-Oldak J. Amelogenin and enamel biomimetics. J Mater Chem B 2015. [DOI: 10.1039/c5tb00163c and 21=21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mature tooth enamel is acellular and does not regenerate itself.
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Affiliation(s)
- Qichao Ruan
- Center for Craniofacial Molecular Biology
- Herman Ostrow School of Dentistry
- University of Southern California
- Los Angeles
- USA
| | - Janet Moradian-Oldak
- Center for Craniofacial Molecular Biology
- Herman Ostrow School of Dentistry
- University of Southern California
- Los Angeles
- USA
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35
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Bidlack FB, Huynh C, Marshman J, Goetze B. Helium ion microscopy of enamel crystallites and extracellular tooth enamel matrix. Front Physiol 2014; 5:395. [PMID: 25346697 PMCID: PMC4193210 DOI: 10.3389/fphys.2014.00395] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 09/23/2014] [Indexed: 01/21/2023] Open
Abstract
An unresolved problem in tooth enamel studies has been to analyze simultaneously and with sufficient spatial resolution both mineral and organic phases in their three dimensional (3D) organization in a given specimen. This study aims to address this need using high-resolution imaging to analyze the 3D structural organization of the enamel matrix, especially amelogenin, in relation to forming enamel crystals. Chemically fixed hemi-mandibles from wild type mice were embedded in LR White acrylic resin, polished and briefly etched to expose the organic matrix in developing tooth enamel. Full-length amelogenin was labeled with specific antibodies and 10 nm immuno-gold. This allowed us to use and compare two different high-resolution imaging techniques for the analysis of uncoated samples. Helium ion microscopy (HIM) was applied to study the spatial organization of organic and mineral structures, while field emission scanning electron microscopy (FE-SEM) in various modes, including backscattered electron detection, allowed us to discern the gold-labeled proteins. Wild type enamel in late secretory to early maturation stage reveals adjacent to ameloblasts a lengthwise parallel alignment of the enamel matrix proteins, including full-length amelogenin proteins, which then transitions into a more heterogeneous appearance with increasing distance from the mineralization front. The matrix adjacent to crystal bundles forms a smooth and lacey sheath, whereas between enamel prisms it is organized into spherical components that are interspersed with rod-shaped protein. These findings highlight first, that the heterogeneous organization of the enamel matrix can be visualized in mineralized en bloc samples. Second, our results illustrate that the combination of these techniques is a powerful approach to elucidate the 3D structural organization of organic matrix molecules in mineralizing tissue in nanometer resolution.
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Affiliation(s)
- Felicitas B Bidlack
- Department of Mineralized Tissue Biology, Forsyth Institute Cambridge, MA, USA ; Department of Developmental Biology, Harvard School of Dental Medicine Boston, MA, USA
| | - Chuong Huynh
- Carl Zeiss Microscopy LLC, One Corporation Way Peabody, MA, USA
| | | | - Bernhard Goetze
- Carl Zeiss Microscopy LLC, One Corporation Way Peabody, MA, USA
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36
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Sanii B, Martinez-Avila O, Simpliciano C, Zuckermann RN, Habelitz S. Matching 4.7-Å XRD spacing in amelogenin nanoribbons and enamel matrix. J Dent Res 2014; 93:918-22. [PMID: 25048248 PMCID: PMC4213250 DOI: 10.1177/0022034514544216] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 06/21/2014] [Accepted: 06/29/2014] [Indexed: 11/15/2022] Open
Abstract
The recent discovery of conditions that induce nanoribbon structures of amelogenin protein in vitro raises questions about their role in enamel formation. Nanoribbons of recombinant human full-length amelogenin (rH174) are about 17 nm wide and self-align into parallel bundles; thus, they could act as templates for crystallization of nanofibrous apatite comprising dental enamel. Here we analyzed the secondary structures of nanoribbon amelogenin by x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) and tested if the structural motif matches previous data on the organic matrix of enamel. XRD analysis showed that a peak corresponding to 4.7 Å is present in nanoribbons of amelogenin. In addition, FTIR analysis showed that amelogenin in the form of nanoribbons was comprised of β-sheets by up to 75%, while amelogenin nanospheres had predominantly random-coil structure. The observation of a 4.7-Å XRD spacing confirms the presence of β-sheets and illustrates structural parallels between the in vitro assemblies and structural motifs in developing enamel.
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Affiliation(s)
- B Sanii
- Lawrence Berkeley National Laboratory, Molecular Foundry, Berkeley, CA 94720, USA Keck Science Department, Claremont McKenna, Scripps and Pitzer Colleges, Claremont, CA 91711, USA
| | - O Martinez-Avila
- University of California, Department of Preventive and Restorative Dental Sciences, San Francisco, CA 94143, USA
| | - C Simpliciano
- University of California, Department of Preventive and Restorative Dental Sciences, San Francisco, CA 94143, USA
| | - R N Zuckermann
- Lawrence Berkeley National Laboratory, Molecular Foundry, Berkeley, CA 94720, USA
| | - S Habelitz
- University of California, Department of Preventive and Restorative Dental Sciences, San Francisco, CA 94143, USA
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37
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Zhu L, Liu H, Witkowska HE, Huang Y, Tanimoto K, Li W. Preferential and selective degradation and removal of amelogenin adsorbed on hydroxyapatites by MMP20 and KLK4 in vitro. Front Physiol 2014; 5:268. [PMID: 25104939 PMCID: PMC4109566 DOI: 10.3389/fphys.2014.00268] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 06/26/2014] [Indexed: 11/23/2022] Open
Abstract
The hardest tooth enamel tissue develops from a soft layer of protein-rich matrix, predominated by amelogenin that is secreted by epithelial ameloblasts in the secretory stage of tooth enamel development. During enamel formation, a well-controlled progressive removal of matrix proteins by resident proteases, Matrix metalloproteinase 20 (MMP20), and kallikrein 4 (KLK4), will provide space for the apatite crystals to grow. To better understand the role of amelogenin degradation in enamel biomineralization, the present study was conducted to investigate how the adsorption of amelogenin to hydroxyapatite (HAP) crystals affects its degradation by enamel proteinases, MMP20 and KLK4. Equal quantities of amelogenins confirmed by protein assays before digestions, either adsorbed to HAP or in solution, were incubated with MMP20 or KLK4. The digested samples collected at different time points were analyzed by spectrophotometry, SDS-PAGE, high performance liquid chromatography (HPLC), and LC-MALDI MS/MS. We found that majority of amelogenin adsorbed on HAP was released into the surrounding solution by enzymatic processing (88% for MMP20 and 98% for KLK4). The results show that as compared with amelogenin in solution, the HAP-bound amelogenin was hydrolyzed by both MMP20 and KLK4 at significantly higher rates. Using LC-MALDI MS/MS, more accessible cleavage sites and hydrolytic fragments from MMP20/KLK4 digestion were identified for the amelogenin adsorbed on HAP crystals as compared to the amelogenin in solution. These results suggest that the adsorption of amelogenin to HAP results in their preferential and selective degradation and removal from HAP by MMP20 and KLK4 in vitro. Based on these findings, a new degradation model related to enamel crystal growth is proposed.
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Affiliation(s)
- Li Zhu
- Department of Orofacial Sciences, School of Dentistry, University of California, San Francisco San Francisco, CA, USA
| | - Haichuan Liu
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco San Francisco, CA, USA
| | - H Ewa Witkowska
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco San Francisco, CA, USA
| | - Yulei Huang
- Department of Oral Medicine, Guanghua School of Stomatology, Sun Yat-sen University Guangdong, China
| | - Kataro Tanimoto
- Departments of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences Hiroshima, Japan
| | - Wu Li
- Department of Orofacial Sciences, School of Dentistry, University of California, San Francisco San Francisco, CA, USA
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Chandrababu KB, Dutta K, Lokappa SB, Ndao M, Evans JS, Moradian-Oldak J. Structural adaptation of tooth enamel protein amelogenin in the presence of SDS micelles. Biopolymers 2014; 101:525-35. [PMID: 24114119 PMCID: PMC3947416 DOI: 10.1002/bip.22415] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 09/13/2013] [Indexed: 11/10/2022]
Abstract
Amelogenin, the major extracellular matrix protein of developing tooth enamel is intrinsically disordered. Through its interaction with other proteins and mineral, amelogenin assists enamel biomineralization by controlling the formation of highly organized enamel crystal arrays. We used circular dichroism (CD), dynamic light scattering (DLS), fluorescence, and NMR spectroscopy to investigate the folding propensity of recombinant porcine amelogenin rP172 following its interaction with SDS, at levels above critical micelle concentration. The rP172-SDS complex formation was confirmed by DLS, while an increase in the structure moiety of rP172 was noted through CD and fluorescence experiments. Fluorescence quenching analyses performed on several rP172 mutants where all but one Trp was replaced by Tyr at different sequence regions confirmed that the interaction of amelogenin with SDS micelles occurs via the N-terminal region close to Trp25 where helical segments can be detected by NMR. NMR spectroscopy and structural refinement calculations using CS-Rosetta modeling confirm that the highly conserved N-terminal domain is prone to form helical structure when bound to SDS micelles. Our findings reported here reveal interactions leading to significant changes in the secondary structure of rP172 upon treatment with SDS. These interactions may reflect the physiological relevance of the flexible nature of amelogenin and its sequence specific helical propensity that might enable it to structurally adapt with charged and potential targets such as cell surface, mineral, and other proteins during enamel biomineralization.
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Affiliation(s)
- Karthik Balakrishna Chandrababu
- Center for Craniofacial Molecular Biology, University of Southern California, School of Dentistry, Los Angeles, California 90033
| | - Kaushik Dutta
- New York Structural Biology Center, 89 Convent Ave, New York, NY 10027
| | - Sowmya Bekshe Lokappa
- Center for Craniofacial Molecular Biology, University of Southern California, School of Dentistry, Los Angeles, California 90033
| | - Moise Ndao
- Laboratory for Chemical Physics, Division of Basic Sciences and Craniofacial Biology, New York University, New York, New York 10010
| | - John Spencer Evans
- Laboratory for Chemical Physics, Division of Basic Sciences and Craniofacial Biology, New York University, New York, New York 10010
| | - Janet Moradian-Oldak
- Center for Craniofacial Molecular Biology, University of Southern California, School of Dentistry, Los Angeles, California 90033
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39
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New insights into the functions of enamel matrices in calcified tissues. JAPANESE DENTAL SCIENCE REVIEW 2014. [DOI: 10.1016/j.jdsr.2014.01.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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40
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Lu JX, Xu YS, Buchko GW, Shaw WJ. Mineral association changes the secondary structure and dynamics of murine amelogenin. J Dent Res 2013; 92:1000-4. [PMID: 24130249 DOI: 10.1177/0022034513504929] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Amelogenin is one of the key protein constituents responsible for the exquisite organization of the calcium phosphate crystals in enamel. Amelogenin forms into nanospheres in solution, while its association with hydroxyapatite is also essential to enamel development. Structural information of full-length amelogenin in either of these physiologically important forms has the potential to provide mechanistic information; however, these data are limited because of the difficulty of determining the structure of large protein complexes and proteins bound to surfaces. To obtain structural insights into amelogenin during these early stages of enamel development, we used a lysine-specific (13)C-, (15)N-labeled sample of murine amelogenin to provide insight into the structure of the hydroxyapatite (HAP)-binding domains of the protein. A combination of one-and two-dimensional solid-state NMR experiments was used to obtain molecular-level insights into the secondary structure and dynamics of full-length amelogenin within a nanosphere-gel and on the surface of HAP. Regions of amelogenin that appear to be primarily random coil in the nanosphere-gel adopt a β-strand structure and are less mobile with HAP binding, indicative of a structural switch upon binding that may be important in the role of amelogenin in enamel development.
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Affiliation(s)
- J X Lu
- Pacific Northwest National Laboratory, Richland, WA 99352, USA
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41
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Gallon V, Chen L, Yang X, Moradian-Oldak J. Localization and quantitative co-localization of enamelin with amelogenin. J Struct Biol 2013; 183:239-49. [PMID: 23563189 PMCID: PMC3737400 DOI: 10.1016/j.jsb.2013.03.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 03/11/2013] [Accepted: 03/25/2013] [Indexed: 02/07/2023]
Abstract
Enamelin and amelogenin are vital proteins in enamel formation. The cooperative function of these two proteins controls crystal nucleation and morphology in vitro. We quantitatively analyzed the co-localization between enamelin and amelogenin by confocal microscopy and using two antibodies, one raised against a sequence in the porcine 32 kDa enamelin region and the other raised against full-length recombinant mouse amelogenin. We further investigated the interaction of the porcine 32 kDa enamelin and recombinant amelogenin using immuno-gold labeling. This study reports the quantitative co-localization results for postnatal days 1-8 mandibular mouse molars. We show that amelogenin and enamelin are secreted into the extracellular matrix on the cuspal slopes of the molars at day 1 and that secretion continues to at least day 8. Quantitative co-localization analysis (QCA) was performed in several different configurations using large (45 μm height, 33 μm width) and small (7 μm diameter) regions of interest to elucidate any patterns. Co-localization patterns in day 8 samples revealed that enamelin and amelogenin co-localize near the secretory face of the ameloblasts and appear to be secreted approximately in a 1:1 ratio. The degree of co-localization decreases as the enamel matures, both along the secretory face of ameloblasts and throughout the entire thickness of the enamel. Immuno-reactivity against enamelin is concentrated along the secretory face of ameloblasts, supporting the theory that this protein together with amelogenin is intimately involved in mineral induction at the beginning of enamel formation.
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Affiliation(s)
- Victoria Gallon
- Center for Craniofacial Molecular Biology, University of Southern California, Herman Ostrow School of Dentistry, Los Angeles, CA 90033, USA
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42
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CryoTEM study of effects of phosphorylation on the hierarchical assembly of porcine amelogenin and its regulation of mineralization in vitro. J Struct Biol 2013; 183:250-7. [PMID: 23707542 DOI: 10.1016/j.jsb.2013.05.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Revised: 04/22/2013] [Accepted: 05/15/2013] [Indexed: 11/21/2022]
Abstract
Amelogenin, the major extracellular enamel matrix protein, plays a critical role in regulating the growth and organization of enamel. Assembly and mineralization of full-length native (P173) and recombinant (rP172) porcine amelogenins were studied by cryogenic Transmission Electron Microscopy (cryoTEM). The cryoTEM revealed that both native and recombinant porcine amelogenins undergo step-wise self-assembly. Although the overall structural organization of P173 and rP172 oligomers was similar and resembled oligomers of murine recombinant amelogenin rM179, there were subtle differences suggesting that a single phosphorylated serine present in P173 might affect amelogenin self-assembly. Our mineralization studies demonstrated that both P173 and rP172 oligomers stabilize initial mineral clusters. Importantly, however, rP172 regulated the organization of initial mineral clusters into linear chains and guided the formation of parallel arrays of elongated mineral particles, which are the hallmark of enamel structural organization. These results are similar to those obtained previously using full-length recombinant murine amelogenin (Fang et al., 2011a). In contrast to that seen with rP172, phosphorylated P173 strongly inhibits mineralization for extended periods of time. We propose that these differences might be due to the differences in the structural organization and charge distribution between P173 and rP172. Overall our studies indicate that self-assembly of amelogenin and the mechanisms of its control over mineralization might be universal across different mammalian species. Our data also provide new insight into the effect of phosphorylation on amelogenin self-assembly and its regulation of mineralization.
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