GENE-EXPRESSION OF GROWTH AND DIFFERENTIATION FACTOR-5, FACTOR-6, ANDFACTOR-7 IN DEVELOPING BOVINE TOOTH AT THE ROOT FORMING STAGE

Growth and differentiation factors (GDF)-5, -6, and -7 are members of the bone morphogenetic protein (BMP) family. Previous studies suggest their importance in bone development and in tendon/ligament morphogene sis. The cells of the dental attachment apparatus, cementum, periodont al ligament, and alveolar bone proper are derived from the dental foll icle proper. In this study, we investigated the expression of GDF-5, - 6, and -7 genes in tissues of the bovine incisor tooth germ at the roo t forming stage. The results demonstrate distinct expression of GDFs i n both the dental follicle and the odontoblast layer. While GDF-5 and -6 mRNAs were expressed in both the dental follicle and the odontoblas t layer, GDF-7 mRNA expression was detected only in the dental follicl e. These results indicate that GDFs, expressed in the bovine tooth ger m including the dental follicle, may be potent regulatory molecules in the development of the dental attachment apparatus. (C) 1998 Academic Press.