Fig. 1

SCUBE3 is expressed during tooth development and translocated from Epi to Mes via the paracrine pathway. A SCUBE3 expression in mouse mandibular first molar tooth germ was detected using immunohistochemistry during tooth development on embryonic day 12.5 (E12.5), E14.5, E16.5, E18.5, and postnatal days 3 (P3) and P7. Boxed areas in (A6, 8) are shown at higher magnification than those in (A5, 7). B Immunohistochemistry for SCUBE3 in mouse incisors on P14. C, D SCUBE3 transcript level in epithelial and mesenchymal tissues of the tooth germ on E16.5, P1, P5, and P10 was evaluated using RT-qPCR. E Immunofluorescence staining of dental Epi and Mes from mouse mandibular first molar tooth germ, LS-8 cells, co-cultured dental Mes, and co-cultured hDPSCs. F SCUBE3 expression in whole-cell lysates of LS-8 cells on the indicated days of ameloblastic differentiation was evaluated using Western blot analyses. Full-length blots/gels are presented in Additional file 3. G Western blot of secretory SCUBE3 in the conditioned medium of LS-8 during ameloblastic differentiation. Full-length blots/gels are presented in Additional file 3. H Expression of SCUBE3 protein in the untreated mMes and co-cultured mMes was evaluated using Western blot. Full-length blots/gels are presented in Additional file 3. i Expression of SCUBE3 mRNA in the untreated mMes and co-cultured mMes was evaluated using RT-qPCR. n = 3 independent biological samples. *P < 0.05, **P < 0.01, ***P < 0.001. Am, ameloblasts. Dp, dental papilla. De, dentin. En, enamel. Epi, epithelial cells. Iee, inner enamel epithelium. Mes, mesenchymal cells. Si, stratum intermedium. Od, odontoblasts. Oee, outer enamel epithelium. hDPSC, human dental pulp stem cell. ECM, extracellular matrix