This continuation project further explores the mechanisms of enamel development and mineralization in the human tooth. It is concerned with the ultrastructural localization and distribution of major enamel proteins, amelogenins and enamelins, in enamel organ cells and in extracellular matrix throughout human amelogenesis from early formation to maturation. These quantitative ultrastructural localization studies will be carried out using the high resolution protein-A gold immunocytochemical method and employing specific polyclonal and monoclonal antibodies against human amelogenin and against enamelin proteins which have recently been produced in our laboratory. These will reveal the mechanisms of synthesis secretion, degradation and resorption of each of these different enamel proteins and their structural relationship with the growing crystallite across the different stages of development. In addition, the primary structure of the major amelogenin and enamelin proteins will be further elucidated and their corresponding genes identified and localized using molecular biology techniques. A tooth enamel (ameloblast) cDNA library will be constructed using our human mRNA which we have now isolated and showed in Northern hybridization experiments to hybridize with a specifically synthesized amelogenin oligonucleotide and in cell-free translation to code for enamel proteins. The cDNA human amelogenin and enamelin clones will in turn be screened by our polyclonal and monoclonal antibodies as well as our specifically synthesized amelogenin oligonucleotide. Corresponding cDNA probes of amelogenin and enamelin will be isolated an sequenced to decipher the primary structures of amelogenin and enamelin. The corresponding cDNA probes will in turn be used t identify and localize the corresponding gene, as well as to prepare specific RNA probes for in situ hybridization studies to determine gene expression of these proteins throughout human amelogenesis. The final mineralization and maturation of surface mature enamel prior to, during, and after tooth eruption will be studied chemically, biochemically and immunologically by determining the changes in composition, concentration and distribution of both mineral and protein components using microsampling, microchemical and immunological methods developed and already used in our laboratory. Such information, together with our past studies, will further contribute to the detailed understanding of the basic mechanisms by which enamel develops and mineralizes in human teeth, and will provide an important baseline for studying normal and abnormal human amelogenesis.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Research Project (R01)
Project #
5R01DE005780-09
Application #
2129263
Study Section
Oral Biology and Medicine Subcommittee 1 (OBM)
Project Start
1982-07-01
Project End
1994-11-01
Budget Start
1992-01-12
Budget End
1994-11-01
Support Year
9
Fiscal Year
1992
Total Cost
Indirect Cost
Name
Hebrew University of Jerusalem
Department
Type
DUNS #
600044978
City
Jerusalem
State
Country
Israel
Zip Code
91904
Catalano-Sherman, J; Laskov, R; Palmon, A et al. (1994) Production of a monoclonal antibody against human amelogenin. Calcif Tissue Int 54:76-80
Deutsch, D; Palmon, A; Young, M F et al. (1994) Mapping of the human tuftelin (TUFT1) gene to chromosome 1 by fluorescence in situ hybridization. Mamm Genome 5:461-2
Catalano-Sherman, J; Palmon, A; Burstein, Y et al. (1993) Amino acid sequence of a major human amelogenin protein employing Edman degradation and cDNA sequencing. J Dent Res 72:1566-72
Deutsch, D; Palmon, A; Fisher, L W et al. (1991) Sequencing of bovine enamelin (""tuftelin"") a novel acidic enamel protein. J Biol Chem 266:16021-8
Sydney-Zax, M; Mayer, I; Deutsch, D (1991) Carbonate content in developing human and bovine enamel. J Dent Res 70:913-6
Deutsch, D (1989) Structure and function of enamel gene products. Anat Rec 224:189-210
Deutsch, D; Shapira, L (1987) Pattern of mineral uptake in the developing human deciduous enamel. J Craniofac Genet Dev Biol 7:137-43
Deutsch, D; Tam, O; Stack, M V (1985) Postnatal changes in size, morphology and weight of developing postnatal deciduous anterior teeth. Growth 49:207-17