Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing 100050, China.
Exp Cell Res. 2013 Nov 1;319(18):2874-82. doi: 10.1016/j.yexcr.2013.07.008. Epub 2013 Jul 18.
Mesenchymal stem cells (MSCs) are a reliable resource for tissue regeneration, but the molecular mechanism underlying directed differentiation remains unclear; this has restricted potential MSC applications. The histone demethylase, lysine (K)-specific demethylase 2A (KDM2A), is evolutionarily conserved and ubiquitously expressed members of the JmjC-domain-containing histone demethylase family. A previous study determined that KDM2A can regulate the cell proliferation and osteo/dentinogenic differentiation of MSCs. It is not known whether KDM2A is involved in the other cell lineages differentiation of MSCs. Here, we show that depletion of KDM2A by short hairpin RNAs can enhance adipogenic and chondrogenic differentiation potentials in human stem cells from apical papilla (SCAPs). We found that the stemness-related genes, SOX2, and the embryonic stem cell master transcription factor, NANOG were significantly increased after silence of KDM2A in SCAPs. Moreover, we found that knock-down of the KDM2A co-factor, BCOR also up-regulated the mRNA levels of SOX2 and NANOG. Furthermore, Chromatin immunoprecipitation assays demonstrate that silence of KDM2A increased the histone H3 Lysine 4 (H3K4) trimethylation in the SOX2 and NANOG locus and regulates its expression. In conclusion, our results suggested that depletion of KDM2A enhanced the adipogenic and chondrogenic differentiation potentials of SCAPs by up-regulated SOX2 and NANOG, BCOR also involved in this regulation as co-factor, and provided useful information to understand the molecular mechanism underlying directed differentiation in MSCs.
间充质干细胞(MSCs)是组织再生的可靠资源,但定向分化的分子机制尚不清楚;这限制了潜在 MSC 应用。组蛋白去甲基酶赖氨酸(K)特异性去甲基酶 2A(KDM2A)是进化上保守的、广泛表达的 JmjC 结构域包含组蛋白去甲基酶家族成员。先前的研究表明,KDM2A 可以调节 MSCs 的细胞增殖和成骨/牙本质分化。目前尚不清楚 KDM2A 是否参与 MSCs 的其他细胞谱系分化。在这里,我们通过短发夹 RNA 敲低实验发现 KDM2A 的缺失可以增强人根尖乳头干细胞(SCAPs)的成脂和成软骨分化潜能。我们发现沉默 KDM2A 后,干细胞相关基因 SOX2 和胚胎干细胞主转录因子 NANOG 的表达显著增加。此外,我们发现 KDM2A 共因子 BCOR 的敲低也上调了 SOX2 和 NANOG 的 mRNA 水平。此外,染色质免疫沉淀实验表明,沉默 KDM2A 增加了 SOX2 和 NANOG 基因座的组蛋白 H3 赖氨酸 4(H3K4)三甲基化,并调节其表达。总之,我们的研究结果表明,通过上调 SOX2 和 NANOG,KDM2A 的缺失增强了 SCAPs 的成脂和成软骨分化潜能,BCOR 作为共因子也参与了这种调节,为理解 MSCs 定向分化的分子机制提供了有用的信息。