Tissue regeneration mediated by mesenchymal stem cells (MSCs) is deemed a desirable way to repair teeth and craniomaxillofacial tissue defects. Nevertheless, the molecular mechanisms about cell proliferation and committed differentiation of MSCs remain obscure. Previous researches have proved that lysine demethylase 2A (KDM2A) performed significant function in the regulation of MSC proliferation and differentiation. SNRNP200, as a co-binding factor of KDM2A, its potential effect in regulating MSCs’ function is still unclear. Therefore, stem cells from the apical papilla (SCAPs) were used to investigate the function of SNRNP200 in this research. The alkaline phosphatase (ALP) activity assay, Alizarin Red staining, and osteogenesis-related gene expressions were used to examine osteo−/dentinogenic differentiation potential. Carboxyfluorescein diacetate, succinimidyl ester (CFSE) and cell cycle analysis were applied to detect the cell proliferation. Western blot analysis was used to evaluate the expressions of cell cycle-related proteins. Depletion of SNRNP200 caused an obvious decrease of ALP activity, mineralization formation and the expressions of osteo−/dentinogenic genes including RUNX2, DSPP, DMP1 and BSP. Meanwhile, CFSE and cell cycle assays revealed that knock-down of SNRNP200 inhibited the cell proliferation and blocked cell cycle at the G2/M and S phase in SCAPs. In addition, it was found that depletion of SNRNP200 up-regulated p21 and p53, and down-regulated the CDK1, CyclinB, CyclinE and CDK2. Depletion of SNRNP200 repressed osteo−/dentinogenic differentiation potentials and restrained cell proliferation through blocking cell cycle progression at the G2/M and S phase, further revealing that SNRNP200 has crucial effects on preserving the proliferation and differentiation potentials of dental tissue-derived MSCs.

中文翻译：

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SNRNP200 的消耗会抑制根尖乳头干细胞的骨/牙本质分化和细胞增殖潜力


由间充质干细胞（MSC）介导的组织再生被认为是修复牙齿和颅颌面组织缺陷的理想方法。然而，关于细胞增殖和间充质干细胞定向分化的分子机制仍然不清楚。前期研究证明赖氨酸去甲基酶2A（KDM2A）在MSC增殖和分化的调控中发挥着重要作用。 SNRNP200作为KDM2A的共结合因子，其调节MSCs功能的潜在作用尚不清楚。因此，本研究使用来自顶乳头（SCAP）的干细胞来研究SNRNP200的功能。碱性磷酸酶（ALP）活性测定、茜素红染色和成骨相关基因表达用于检查骨/牙本质分化潜力。应用羧基荧光素二乙酸酯、琥珀酰亚胺酯(CFSE)和细胞周期分析来检测细胞增殖。 Western blot分析用于评估细胞周期相关蛋白的表达。 SNRNP200 的消耗导致 ALP 活性、矿化形成以及骨/牙本质基因（包括 RUNX2、DSPP、DMP1 和 BSP）的表达明显降低。同时，CFSE和细胞周期测定表明，SNRNP200的敲除抑制了SCAP中的细胞增殖并阻断了细胞周期在G2/M和S期。此外，发现SNRNP200的缺失上调p21和p53，下调CDK1、CyclinB、CyclinE和CDK2。 SNRNP200的耗竭抑制了骨/牙本质分化潜能，并通过阻断G2/M和S期的细胞周期进展来抑制细胞增殖，进一步揭示SNRNP200对于保持牙组织来源的MSC的增殖和分化潜能具有至关重要的作用。