成牙本质细胞中上游刺激因子1的表达、细胞内定位及转位研究

Expression,subcellular localization and nuclear translocation of transcription factor up stream stimulatory fator-1 in odontoblasts

目的检测成牙本质细胞中上游刺激因子1(upstream stimulatory factor-1,USF1)蛋白的表达及细胞内定位,并探讨其能否发生核转位。方法培养成牙本质细胞 MDPC-23,一组作为对照组不给刺激,另一组作为实验组经不同浓度尼古丁硫酸盐(25、50、75及100 mg/L)刺激1 h 后分别制备细胞爬片,用抗 USF1抗体,常规 SABC 法检测,以 Hela 细胞为阳性对照。结果对照组成牙本质细胞质中有较强的黄褐色颗粒,但100 mg/L 尼古丁作用组胞核中有较强的黄褐色着色,胞质着色减弱,其他刺激组仅表现为胞质黄褐色,而阳性对照 Hela 细胞核中有较强的黄褐色着色。结论体外培养的成牙本质细胞中有 USF1蛋白表达,定位于细胞质、在尼古丁的刺激下可发生核转位。

Objective To examine the expression and subceUular localization of transcription factor USF1 in odontoblasts and investigate whether nuclear translocation occurs under stimuli. Methods Odontoblasts MDPC-23 were cultured on eoverslips and divided into 2 groups. Group 1 received no stimuli, and group 2 was stimulated by nicotine with various concentrations respectively for 1 h. Then the mountings of odontoblasts were prepared and immunoeytochemieal staining was performed with specific USF1 antibody via SABC method. Hela cells were used as positive control. Results The staining was positive in the cytoplasm of odontoblasts in group 1, but in the nuclei of Hela cells and in 100 mg,/L nicotine-stimulated edontoblasts in group 2. Conclusions There exists USF1 protein in edontoblasts, which locates in the cytoplasm and could transloeate into nuclei under the stimulation of nicotine.