MicroRNAs靶向DLX-5调控Osterix在成牙骨质细胞分化中的机制研究

Transcription factor osteorix(Osx) have a vital role in modulating dental follicle cell differentiation toward cementoblast and subsequent cementogenesis during root formation. MicroRNA (miRNA）are nucleotide non-coding RNAs that bind to mRNAs through an imperfect match to repress their translation. miRNAs play an important role in cell fate determination and differentiation. DLX-5 is involved in cementogensis and is a target gene of miRNA. In this study, dental follicle cell is induced with recombinant bmp-2, an established model for studying cementoblast differentiation. Expression of miRNAs before and after BMP-2 treatment will be analyzed using qRT-PCR. Target prediction is to be carried out and miRNAs target DLX-5 will be chosen and verified using gain-of-function technology. Luciferase assay for miRNA mediated mRNA reduction will also be performed. This study will revealed mechanism of differentiation of dental follicle cell toward cementoblast via miRNA pathway, and is helpful to provide new direction for the research of periodontal reconstruction.

牙根形成过程中牙囊细胞分化成为成牙骨质细胞进而生成牙骨质，转录因子Osx起至关重要的作用，此分化过程中Osx的调控机制尚未明确。非编码小分子RNA（miRNA）参与调控几乎所有干细胞的分化及细胞命运决定，可靶向结合并降解mRNA实现对基因表达的调控。目前已知同源盒基因DLX-5参与了牙骨质细胞分化的调控，miRNA可直接靶向DLX-5参与转录后水平调控，申请人在前期研究中发现，牙骨质细胞分化过程中miRNA随Osx基因的上调发生表达变化。本课题拟以BMP-2诱导牙囊细胞向成牙骨质细胞分化为模型，采用定量PCR等筛选参与调控Osx的miRNAs。通过miRNA靶基因预测及靶标的荧光素酶检测，特定分析miRNA靶向DLX-5在转录后水平调控Osx在成牙骨质细胞分化。本课题将验证牙骨质细胞分化中Osx起的关键作用及阐明miRNA对Osx调控机制，可为牙骨质再生提供理论依据。

牙根形成过程中牙囊细胞分化成为成牙骨质细胞进而生成牙骨质,转录因子Osx起至关重要的作用，此分化过程中Osx的调控机制尚未明确。非编码小分子RNA（miRNA）参与调控几乎所有干细胞的分化及细胞命运决定，可靶向结合并降解mRNA实现对基因表达的调控。本课题以骨诱导培养液诱导牙囊干细胞及骨髓间充质细胞向成牙骨质/成骨细胞分化为模型，采用定量PCR等研究miR-124参与调控Osx的情况。我们证实了miR-124靶向Osterix在调控成牙骨质/成骨细胞向分化的关键作用。此外，课题组探讨了一种含纳米载体的新型骨矿化诱导液体对成骨细胞向分化中的作用，研究了一种促进I型胶原的功能性矿化—胶原内矿化（intrafibrillar）的方法，研究结果将为牙骨质再生提供重要的理论依据。