Effects of transforming growth factor-131 on odontoblastic differentiation in dental papilla cells is determined by IPO7 expression level

Transforming growth factor 131 (TGF-131) is one of the broad-spectrum growth-promoting factors that participate in tooth development. The influence of TGF-131 on the odontoblastic differentiation is still controvercy. Mouse primary dental papilla cells (mDPCs) as well as an immortalized mouse dental papilla cell line (mDPC6Ts) were treated with exogenous TGF-131 during odontoblastic differentiation. RTqPCR, Western blot, alizarin red staining and ALP staining were carried out to investigate the influence of TGF-131 on odontoblastic differentiation. IPO7, important for SMAD complex translocation was also detected in mDPCs and mDPC6Ts in response to TGF-131. After silencing IPO7 by transfection, the translocation process of P-SMAD2 was investigated by nuclear and cytoplasmic extraction as well as coimmunoprecipitation assay. The odontogenic markers, mineralization and IPO7 expression were significantly up-regulated in TGF-131-treated mDPCs while down-regulated in mDPC6Ts. The total level of PSMAD2 was not influenced by IPO7 in mDPCs, however, IPO7 could bind to P-SMAD2 and affect the nuclear-cytoplasm-shuttling of P-SMAD2. Our data demonstrated that TGF-131 plays opposite roles in odontoblast differentiation in mDPCs and immortalized mouse dental papilla cell line (mDPC6Ts), which is determined by IPO7. (c) 2021 Published by Elsevier Inc. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).

Automated summary

TGF-131 plays dual roles in odontoblast differentiation in mouse dental papilla cells, which is determined by IPO7.