COUP-TFII Stimulates Dentin Sialophosphoprotein Expression and Mineralization in Odontoblasts

Abstract

Chicken ovalbumin upstream promoter transcription factor 2 (COUP-TFII), an orphan nuclear receptor belonging to the steroid-thyroid hormone receptor superfamily, plays an important role in cell fate determination of various tissues. However, the specific role of COUP-TFII in tooth development has not yet been elucidated. In the present study, we aimed to explore the role of COUP-TFII in dentin sialophosphoprotein (DSPP) expression and matrix mineralization in odontoblast-lineage cells. In primary human dental pulp cells (HDPCs) and murine dental papilla-derived cells (MDPC-23) cultured in a mineralizing medium, the expression of COUP-TFII was induced along with the increased odontoblast-specific dentin matrix protein-1 (DMP-1) and DSPP expression. Endogenous expression of COUP-TFII in maxillary second molar germs of rats showed an increasing tendency as development of the tooth progressed. Also, COUP-TFII protein was detected in greater quantity in the odontoblastic layer of second molar germs than in that of third molar germs of rats. Overexpression of COUP-TFII using an adenoviral system upregulated the expression of odontoblast-specific genes with increased alkaline phosphatase activity and matrix mineralization in odontoblast-lineage cells. In contrast, knockdown of COUP-TFII using small interfering RNA decreased the expression of odontoblast-specific genes, which reduced matrix mineralization. Mechanistic studies revealed that COUP-TFII increased DSPP transcription by direct binding on the DSPP promoter. In addition, COUP-TFII physically interacted with the homeodomain transcription factor Msx2 and antagonistically regulated the Msx2 effect on DSPP promoter activity. Taken together, these results suggest that COUP-TFII has a stimulatory role in DSPP expression and matrix mineralization in odontoblast-lineage cells.

FGF2 Stimulates COUP-TFII Expression via the MEK1/2 Pathway to Inhibit Osteoblast Differentiation in C3H10T1/2 Cells

“…After 4 h of incubation with the siRNAs–liposome complex, the cells were changed with 2% FBS-containing media and cultured for 24 h. The cells were then treated with FGF2 with or without the indicated chemical inhibitors for 24 h. Pre-designed and validated siRNAs were used as follows: COUP-TFII Silencer Pre-designed siRNA (ID#139842, CAT# AM16708; Ambion/Thermo Fisher Scientific). The specificity and efficacy of this siRNA was validated in a previous study [ 17 ]. Knockdown of MEK2 was accomplished using two distinct non-overlapping siRNAs against MEK2, si-MEK2 #1 (AccuTarget siRNA, #1383748 Duplex; Bioneer, Daejeon, South Korea) and si-MEK2 #2 (AccuTarget siRNA, #1383749, Duplex; Bioneer).…”

mTORC1 promotes mineralization via p53 pathway

“…Previous studies have shown that dentin sialophosphoprotein (DSPP), dentin matrix protein 1 (DMP1), type 1 collagen (COL1), and alkaline phosphatase (ALP) are markers of odontoblast mineralization. 3,4 Klf10 and testicular acid phosphatase have been reported to play important roles in promoting odontoblast mineralization, [5][6][7] but the regulatory mechanism of odontoblast mineralization is still undefined. Thus, identifying factors that effectively promote odontoblast mineralization and determining the regulatory mechanism of odontoblast mineralization were major goals of this study.…”

An NKX-COUP-TFII genomic code for mucosal vascular addressins and organ morphogenesis

“…We show that an evolutionarily conserved NCCE in the Nrp2 promoter supports NKX2-1/COUP-TFII interaction and reporter activation (Figure S12A, F and G). NCCE are also enriched among genes implicated in inner ear morphogenesis; in odontogenesis (which involves COUP-TFII and NKX2-3 (Han et al, 2018; Hur et al, 2015); and pancreatic beta cell fate specification (regulated by COUP-TFII and NKX2-2 (Boutant et al, 2012; Gutierrez et al, 2017; Papizan et al, 2011). In contrast, genes in which NKX and COUP-TFII sites are all separated by 30-60 bp show significantly less enrichment in NCCE-associated GO terms for morphogenesis or organogenesis, and/or are enriched in distinct embryonic and developmental processes.…”