Press T, Viale-Bouroncle S, Felthaus O, Gosau M, Morsczeck C
Department of Cranio- and Maxillofacial Surgery, University Hospital Regensburg, Regensburg, Germany.
Int Endod J. 2015 Feb;48(2):185-92. doi: 10.1111/iej.12299. Epub 2014 Jun 25.
To evaluate whether and how the transcription factor early growth response gene 1 (EGR1) affects the osteogenic differentiation of dental stem cells.
Dental stem cells from apical papilla (SCAPs) and from the dental follicle (DFCs) were transfected with EGR1-specific siRNA or EGR-1 expression plasmid. Gene regulation was verified at protein level by Western blotting. The expression of the transcription factors distal-less homeobox 3 (DLX3), alkaline phosphatase (ALP) and bone morphogenetic protein 2 (BMP2), which are all regulators and markers of the osteogenic differentiation in dental stem cells, was determined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). To investigate mineralization, SCAP long-term cultures were stained with alizarin red after EGR1 over-expression.
EGR1 was induced in SCAPs during osteogenic differentiation. DLX3 and bone morphogenetic protein 2 (BMP2) were up-regulated after EGR1 over-expression and down-regulated after EGR1 depletion. The expression of ALP was also down-regulated after EGR1 depletion. The over-expression of EGR1 in SCAPs promoted mineralization after osteogenic differentiation.
EGR1 supported the osteogenic differentiation of dental stem cells by potentially regulating the expression of DLX3 and BMP2.
评估转录因子早期生长反应基因1（EGR1）是否以及如何影响牙源性干细胞的成骨分化。
用EGR1特异性小干扰RNA（siRNA）或EGR-1表达质粒转染来自根尖乳头的牙源性干细胞（SCAPs）和来自牙囊的牙源性干细胞（DFCs）。通过蛋白质印迹法在蛋白质水平验证基因调控。通过定量逆转录-聚合酶链反应（qRT-PCR）测定远端缺失同源盒3（DLX3）、碱性磷酸酶（ALP）和骨形态发生蛋白2（BMP2）的表达，这些都是牙源性干细胞成骨分化的调节因子和标志物。为了研究矿化情况，在EGR1过表达后，对SCAP长期培养物进行茜素红染色。
在成骨分化过程中，SCAPs中EGR1被诱导。EGR1过表达后，DLX3和骨形态发生蛋白2（BMP2）上调，EGR1缺失后下调。EGR1缺失后，ALP的表达也下调。SCAPs中EGR1的过表达促进了成骨分化后的矿化。
EGR1可能通过调节DLX3和BMP2的表达来支持牙源性干细胞的成骨分化。
