Fig. 3

Exogenous SCUBE3 promotes odontoblastic differentiation of hDPSCs via the BMP2/Smad pathway. The cells were exposed to exogenous rhSCUBE3 to explore the differentiation and mechanism of exogenous SCUBE3 in hDPSCs. A RT-qPCR was performed to verify the activation of the BMP signalling pathway downstream effectors BMP2, BMP4, BMPR1A, and BMPR1B by SCUBE3. BMP2 and BMPR1A presented the most significant difference relative to the control. B HDPSCs were further treated with exogenous rhSCUBE3 or rhSCUBE3 with the BMP2 pathway inhibitor LDN-193189. Western blot analysis was used to detect the BMP signalling pathway downstream effectors BMP2, BMPR1A, Smad1, and p-Smad1/5 expression. Full-length blots/gels are presented in Additional file 3. C The expression of the odontoblastic differentiation markers DSPP, DMP1, OPN, and OSX in hDPSCs treated with rhSCUBE3 or rhSCUBE3 with LDN-193189 was assessed using RT-qPCR. D The expression of the odontoblastic differentiation markers in hDPSCs treated with rhSCUBE3 or rhSCUBE3 with LDN-193189 was assessed using Western blot analyses. Full-length blots/gels are presented in Additional file 3. E Alizarin R staining. F Alkaline phosphatase activity staining. n = 3 independent biological samples. *P < 0.05, **P < 0.01, ***P < 0.001. LDN, LDN-193189