The expression of transcriptional factors and non-collagenous proteins in the differentiation of bone cells.

我们检测了大鼠下颌骨成骨过程中成骨细胞/骨细胞因子45 (OF45) mRNA的原位定位。在胚胎大鼠颅骨细胞（FRCC）和原代大鼠骨髓基质细胞（SBMC）等大鼠成骨样细胞培养过程中，以及在两种不同分化阶段的克隆大鼠成骨细胞系中，检测了转录因子和成骨相关蛋白如OF45、牙本质基质蛋白1（Dmp1）、骨钙素（OC）、骨涎蛋白（BSP）和骨桥蛋白（OPN）的基因表达。在存在或不存在有效的合成糖皮质激素地塞米松（Dex）或骨形态发生蛋白2（BMP-2）的情况下，robc - c26和ROS 17/2.8细胞。这些实验结果得到了以下结论。1.OF45 mRNA由成熟的成骨细胞短暂表达，随后在骨骼的整个骨化过程中由骨细胞表达，该蛋白代表了骨细胞表型的重要市场，最有可能参与调节骨细胞的功能。2.Dex在FRCC中诱导Runx2和Osterix mrna，可能随后激活成骨细胞标记基因，如OC和BSP mrna，产生骨特异性基质，随后矿化。因此，Dex可能通过诱导Runx2和Osterix基因的体外表达，促进FRCC成骨分化和矿化。3.与Dmp1、OC、BSP和OPN相比，Dex对SBMC中OF45基因的表达有较强的诱导作用。4.ROS 17/2.8细胞中转录因子（AJ18、Osterix和Dlx5）和蛋白（碱性磷酸酶、OC、BSP和OPN）的基因表达受Dex控制，且在Dex存在或不存在的情况下与矿化相关。robo - c26细胞中AJ18和Runx2 mRNA的表达受BMP-2和TGF-β1的控制，两者对AJ18 mRNA表达的影响不同，但在成骨细胞分化过程中是Runx2 mRNA表达的有效刺激物。少

We examined in situ localization of osteoblast/osteocyte factor 45 (OF45) mRNA during bone formation in developing rat mandible. Gene expression of the transcription factors and oseoblast-related proteins such as OF45,dentin matrix protein 1(Dmp1), osteocalcin(OC), bone sialoprotein(BSP) and osteopontin(OPN) was also examined during cell culture not only in primary rat osteoblast-like cells such as differentiating fetal rat calvarial cells(FRCC) and primary rat stromal bone marrow cells(SBMC), but also in two clonal rat osteoblastic cell lines with different stages of differentiation, ROB-C26 and ROS 17/2.8 cells in the presence or absence of a potent, synthetic glucocorticoid dexamethasone(Dex) or bone morphogenetic protein 2(BMP-2). These experimental results obtained the following conclusions. 1.OF45 mRNA is transiently expressed by mature osteoblasts and subsequently expressed by osteocytes throughout ossification in the skeleton and this protein represents to be an important marke … More r of the osteocyte phenotype and most likely participates in regulating osteocyte function. 2.Induction of Runx2 and Osterix mRNAs in FRCC by Dex may be followed by activation of osteoblast marker genes such as OC and BSP mRNAs to produce a bone-specific matrix that subsequently becomes mineralized. Thus, it is likely that Dex may promote osteoblastic differentiation and mineralization of FRCC by inducing the expression of Runx2 and Osterix genes in vitro. 3.Gene expression of OF45 in SBMC is induced strongly by Dex when compared with that of Dmp1,OC, BSP and OPN. 4.The gene expression of the transcription factors (AJ18,Osterix and Dlx5) and the proteins (alkaline phosphatase, OC, BSP and OPN) in ROS 17/2.8 cells is under the control of Dex and is altered associated with mineralization even in the presence or absence of Dex. 5.The expression of AJ18 and Runx2 mRNAs in ROB-C26 cells is under the control of BMP-2 and TGF-β1, both of which exert different effects on AJ18 mRNA expression, but are potent stimulators of Runx2 mRNA expression during osteoblast differentiation. Less