Our purpose was to determine how enamel matrix derivative (EMD) affects the expression of osteogenesis-and chondrogenesis-related transcription factors in undifferentiated mesenchymal cells.C3H10T1/2 cell line, a typical pluripotential mesenchymal cell line, was cultured with or without EMD for up to 7 d. Expression of mRNAs encoding osteogenesis-and chondrogenesis-related transcription factors(Runx2, Osterix, AJ18, Dlx5, Msx2, Sox5, Sox9 and Zfp60) was measured using real-time polymerase chain reaction. Runx2 and Sox9 protein expression and the presence of bone morphogenetic protein (BMP)-6-like molecules in EMD were determined by Weste blotting. EMD substantially increased mRNA levels of osteogenesis-and chondrogenesis-related transcription factors. EMD also induced Runx2 and Sox9 protein expression. Weste blotting analysis of EMD using anti-BMP-6 antibody revealed immunoreactive bands corresponding to about 14 kDa and 60 kDa. These results suggest that EMD stimulates osteogenesis-and chondrogenesis-related transcription factors, and these activities may be mediated, at least in part, by BMP-6in EMD.