Tooth development is a complex schedule of cell division, differentiation, morphogenesis and tissue-specific extracellular matrix biomineralization. The major objective of this research project is to determine if locally produced growth factors, acting as autocrine and/or paracrine mediators, regulate dentine and enamel biomineralization. We propose to test the hypothesis that time and position-restricted growth factor expression regulates dentine and enamel biomineralization. A recently developed simple organ culture system devoid of exogenous serum or plasma supplementation provides a controlled model to test our hypothesis. The following specific aims are designed to test our hypothesis: (i) to identify and quantitate locally produced growth factor mRNAs and translation products during dental tissue biomineralization; (ii) to determine the timing and position of selected growth factor expression; (iii) to determine if selected exogenous growth factors down-regulate local transcription of growth factors; (iv) to determine if endocrine hormones (e.g. growth hormone) up-regulate locally produced growth factors and stimulate biomineralization; and (v) to determine the function(s) of selected growth factors in dentine and enamel biomineralization. Methods employed include microdissection of embryonic mouse molar tooth organs, organ culture using serumless and chemically-defined medium, mRNA phenotyping using RT-PCT, in situ hybridization, immunocytochemistry, microinjection, immunoperturbation and antisense assays, light and electron microscopy, electron diffraction assays, and computer-assisted three- dimensional reconstruction. These studies use embryonic, fetal and neonatal Swiss Webster strain mouse molar tooth organs.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Research Project (R01)
Project #
5R01DE006425-08
Application #
3219997
Study Section
Oral Biology and Medicine Subcommittee 1 (OBM)
Project Start
1984-03-01
Project End
1993-02-28
Budget Start
1991-03-01
Budget End
1992-02-29
Support Year
8
Fiscal Year
1991
Total Cost
Indirect Cost
Name
University of Southern California
Department
Type
Schools of Dentistry
DUNS #
041544081
City
Los Angeles
State
CA
Country
United States
Zip Code
90089
Caton, Javier; Bringas Jr, Pablo; Zeichner-David, Margarita (2005) IGFs increase enamel formation by inducing expression of enamel mineralizing specific genes. Arch Oral Biol 50:123-9
Takahashi, K; Yamane, A; Bringas, P et al. (1998) Induction of amelogenin and ameloblastin by insulin and insulin-like growth factors (IGF-I and IGF-II) during embryonic mouse tooth development in vitro. Connect Tissue Res 38:269-78;discussion 295-303
Slavkin, H C; Diekwisch, T G (1997) Molecular strategies of tooth enamel formation are highly conserved during vertebrate evolution. Ciba Found Symp 205:73-80; discussion 81-4
Slavkin, H C; Diekwisch, T (1996) Evolution in tooth developmental biology: of morphology and molecules. Anat Rec 245:131-50
Hu, J C; Zhang, C; Slavkin, H C (1995) The role of platelet-derived growth factor in the development of mouse molars. Int J Dev Biol 39:939-45
Diekwisch, T G; Berman, B J; Gentner, S et al. (1995) Initial enamel crystals are not spatially associated with mineralized dentine. Cell Tissue Res 279:149-67
Nakamura, M; Bringas Jr, P; Nanci, A et al. (1994) Translocation of enamel proteins from inner enamel epithelia to odontoblasts during mouse tooth development. Anat Rec 238:383-96
Diekwisch, T; David, S; Bringas Jr, P et al. (1993) Antisense inhibition of AMEL translation demonstrates supramolecular controls for enamel HAP crystal growth during embryonic mouse molar development. Development 117:471-82
Slavkin, H C (1993) Rieger syndrome revisited: experimental approaches using pharmacologic and antisense strategies to abrogate EGF and TGF-alpha functions resulting in dysmorphogenesis during embryonic mouse craniofacial morphogenesis. Am J Med Genet 47:689-97;discussion 687-8
Shum, L; Sakakura, Y; Bringas Jr, P et al. (1993) EGF abrogation-induced fusilli-form dysmorphogenesis of Meckel's cartilage during embryonic mouse mandibular morphogenesis in vitro. Development 118:903-17

Showing the most recent 10 out of 23 publications