Expression of circadian clock genes during differentiation of rat dental papilla cells in vitro

ABSTRACT

The circadian clock is involved in many physiological processes including teeth development. The expression of circadian core clock genes was observed in various tissues, but their role in odontoblasts is unclear. The aim of this study was to investigate the circadian core clock gene expressions of dental papilla cells (DPCs) during the odontogenic differentiation. Primary DPCs were obtained from the first molar dental papilla of neonatal rats and cultured in osteogenic (OS) medium for differentiation in vitro. Reverse transcription and quantitative PCR was performed to assess the mRNA levels of the circadian core clock genes Bmal1, Per2, Cry1, Clock, Rev-erb α and Ror α. Western blotting was performed to assess the protein levels of BMAL1 and PER2. The results showed that apparent oscillatory expression patterns of Per2, Cry1, Rev-erb α could be observed in DPCs, whether differentiated or not. The protein level of BMAL1 was significantly increased and PER2 was decreased during odontogenic differentiation. Taken together, these findings demonstrate that circadian rhythmicity of known core clock genes exist in cultured DPCs in vitro, and the expression of genes change during differentiation process.

KEYWORDS:

• Circadian clock
• dental papilla cell
• differentiation

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported in part by grants from the National Natural Science Foundation of China (Grant No. 81870737, 81371107 and 81470760).