Department of Endodontics, School and Hospital of Stomatology, China Medical University, No. 117, Nanjing North Street, Heping District, Shenyang, 110002, Liaoning Province, China.
Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, 110002, China.
Cell Tissue Res. 2020 Dec;382(3):487-498. doi: 10.1007/s00441-020-03246-1. Epub 2020 Aug 3.
Accumulating research continues to highlight the notable role of microRNAs (miRs) and long non-coding RNAs (lncRNAs) as important regulators in the process of human dental pulp stem cell (hDPSCs) differentiation. The current study aimed to investigate the novel regulatory circuitry of lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)/miR-140-5p/G protein-coupled receptor (GPCR)-kinase 2 interacting protein 2 (GIT2) on the odontogenic differentiation of hDPSCs. In hDPSCs, miR-140-5p was downregulated during the odontogenic differentiation, which was verified to directly target GIT2. RNA crosstalk determined by dual-luciferase reporter and RNA pull-down assays revealed that MALAT1 could bind to miR-140-5p to upregulate the expression of GIT2. After that, the levels of MALAT1, miR-140-5p, and GIT2 in hDPSCs were up- or downregulated by exogenous transfection or lentivirus infection in order to investigate their effects on the differentiation of hDPSCs. It was observed that elevation of miR-140-5p or knockdown of GIT2 resulted in inhibited alkaline phosphatase (ALP) activity, expression of dentin sialophosphoprotein (DSPP), dentin matrix-protein-1 (DMP-1), and distal-less homeobox 3 (DLX3) as well as positive expression of desmoplakin (DSP) protein. The promotive effects of MALAT1 on odontogenic differentiation were diminished by restoration of miR-140-5p or inhibition of GIT2. Taken together, this study provides valuable evidence suggesting MALAT1 as a potential contributor to the odontogenic differentiation of hDPSCs.
越来越多的研究继续强调微小 RNA（miRNA）和长非编码 RNA（lncRNA）作为人类牙髓干细胞（hDPSC）分化过程中重要调节因子的显著作用。本研究旨在探讨 lncRNA 转移相关肺腺癌转录本 1（MALAT1）/miR-140-5p/G 蛋白偶联受体（GPCR）-激酶 2 相互作用蛋白 2（GIT2）在 hDPSC 成牙分化中的新型调控机制。在 hDPSC 中，miR-140-5p 在成牙分化过程中下调，其被证实可直接靶向 GIT2。双荧光素酶报告和 RNA 下拉实验确定的 RNA 串扰表明，MALAT1 可与 miR-140-5p 结合以上调 GIT2 的表达。之后，通过外源性转染或慢病毒感染上调或下调 hDPSC 中的 MALAT1、miR-140-5p 和 GIT2 的水平，以研究它们对 hDPSC 分化的影响。结果观察到 miR-140-5p 的升高或 GIT2 的敲低导致碱性磷酸酶（ALP）活性、牙本质涎磷蛋白（DSPP）、牙本质基质蛋白-1（DMP-1）和远侧同源盒 3（DLX3）的表达以及桥粒蛋白（DSP）蛋白的阳性表达受到抑制。恢复 miR-140-5p 或抑制 GIT2 可减弱 MALAT1 对成牙分化的促进作用。总之，本研究提供了有价值的证据，表明 MALAT1 可能是 hDPSC 成牙分化的潜在贡献者。
