OBJECTIVETo examine the distributions of beta-catenin and adenomatous polyposis coli (APC) protein in the tooth germ, and obtain the messages of function of the two factors and the relationship between them.

METHODSMice were selected and cohabited with the ratio of female mice to male ones being 2:1, and Embryo day 0.5 was confirmed based on the finding of vaginal plug. The distributions of beta-catenin and APC protein in the Embryos on day 13.5, 14.5, 15.5, 16.5, 17.5 were examined in the paraffin-embedded sections by immunohistochemistry methods.

RESULTSDuring E13.5 d to E17.5 d, positive expression of beta-catenin was found in the oral epithelium and the dental lamina, and became more and more strong. The staining were whole cell. During the bud stage, strong positive expression of APC protein was found in the oral epithelium and the dental lamina, but the expression displayed a down-regulation tendency. The staining was the cytomembrane and cytoplasm. There was negative correlation between beta-catenin and APC protein (P<0.01).

CONCLUSIONThe result of beta-catenin suggests its contribution in the early development of enamel organ and the proliferation of cell. Coincidance of the two factors staining site was found, according to the statistics.