Transcriptional regulation of bone sialoprotein gene by CO2 laser irradiation

• Published in: Journal of Oral Science 2011, Vol.53(1), pp.51-59
• Main Authors: Sasaki, Yoko, Wang, Shuang, Ogata, Yorimasa
• Format: Article
• Language: English
• Subjects: bone sialoprotein; CO2 laser irradiation; osteoblast; transcription
• ISSN: 1343-4934; 1880-4926
• DOI: 10.2334/josnusd.53.51

Bone sialoprotein (BSP), an early marker of osteoblast differentiation, has been implicated in the nucleation of hydroxyapatite during de novo bone formation. Low-power laser irradiation has a stimulating effect on cells and tissues. Although the carbon dioxide (CO2) laser is a hard surgical laser, we have attempted to use it at low energy density to achieve biological alterations. To investigate the effects of CO2 laser irradiation on BSP gene transcription, we used rat osteoblast-like ROS17/2.8 cells. BSP mRNA levels were increased at 12 h after irradiation with the CO2 laser (2 W, 20 s). Transient transfection assays using various sizes of the rat BSP gene promoter linked to the luciferase reporter gene showed that CO2 laser irradiation induced luciferase activity of a -116 to +60 BSP promoter construct (pLUC3) at 12 h in the cells. Transcriptional stimulation by CO2 laser irradiation was abrogated in the pLUC3 construct containing a 2-bp mutation in the fibroblast growth factor 2 response element (FRE). Gel shift analyses showed that CO2 laser irradiation increased the binding of nuclear protein to FRE. These studies demonstrate that CO2 laser irradiation increases BSP transcription via FRE in the rat BSP gene promoter. (J Oral Sci 53, 51-59, 2011)