miRNA expression profiling identifies DSPP regulators in cultured dental pulp cells

Dentin sialophosphoprotein (DSPP), an important marker of odontoblast differentiation, is a prerequisite for tooth development and mineralization; however, the molecular mechanisms of both temporal and spatial regulation remain unknown. MicroRNAs (miRNAs) provide an additional level of control beyond that of transcription factors, which regulate post-transcriptional control of gene expression. The present study was designed to provide a first attempt at an in-depth analysis of dental pulp cells at various odontoblastic differentiation stages to obtain miRNA differential expression patterns, and to determine the contribution of miRNAs in the expression of DSPP during odontoblast differentiation. Dual luciferase reporter assays and qRT-PCR were used to validate miRNAs identified from bioinformatic analyses to determine whether they were able to regulate the DSPP gene in dental pulp cells cultured in a mineralizing medium. The results presented here suggest that DSPP is regulated post-transcriptionally by mir32, mir885-5p and mir586 during odontoblast differentiation.