Establishment of primary cultures for mouse ameloblasts as a model of their lifetime.
To understand how the properties of ameloblasts are spatiotemporally regulated during amelogenesis, two primary cultures of ameloblasts in different stages of differentiation were established from mouse enamel epithelium. Mouse primary ameloblasts (MPAs) prepared from immature enamel epithelium (MPA-I) could proliferate, whereas those from mature enamel epithelium (MPA-M) could not. MPA-M but not MPA-I caused apoptosis during culture. The mRNA expression of amelogenin, a marker of immature ameloblasts, was down-regulated, and that of enamel matrix serine proteiase-1, a marker of mature ameloblasts, was induced in MPA-I during culture. Using green fluorescence protein as a reporter, a visualized reporter system was established to analyze the promoter activity of the amelogenin gene. The region between -1102bp and -261bp was required for the reporter expression in MPA-I. These results suggest that MPAs are valuable in vitro models for investigation of ameloblast biology, and that the visualized system is useful for promoter analysis in MPAs.
Suzawa
Tetsuo
T
Department of Biochemistry, School of Dentistry, Showa University, Tokyo 142-8555, Japan. suzawa@dent.showa-u.ac.jp
Itoh
Nao
N
Takahashi
Naoyuki
N
Katagiri
Takenobu
T
Morimura
Naoko
N
Kobayashi
Yasuna
Y
Yamamoto
Toshinori
T
Kamijo
Ryutaro
R
D000565:Ameloblasts / Q000166:cytology*; D000818:Animals; D017209:Apoptosis; D001973:Bromodeoxyuridine / Q000494:pharmacology; D018929:Cell Culture Techniques / Q000379:methods*; D002454:Cell Differentiation; D049109:Cell Proliferation; D002478:Cells, Cultured; D003743:Dental Enamel / Q000166:cytology*; D017353:Gene Deletion; D017930:Genes, Reporter; D020287:In Situ Nick-End Labeling; D051379:Mice; D011401:Promoter Regions, Genetic
D001973:Bromodeoxyuridine