EGF antisense oligodeoxynucleotides block murine odontogenesis in vitro

The initiation of odontogenesis depends on the site-specific proliferation of mandibular epithelium beginning at Day 11 in embryonic mice. We have previously reported that the local expression of epidermal growth factor mRNA in the murine mandible is developmentally regulated, expressed at Days 9 and 10 immediately prior to the initiation of tooth bud formation at Day 11. Exposure of Day 9 mandibular explants to antisense oligomers of epidermal growth factor blocks the initiation of odontogenesis. These results are the first demonstration of the involvement of epidermal growth factor in the inductive specification of a complex epithelial derivative.