lncRNA HOTAIRM1 promotes osteogenesis of hDFSCs by epigenetically regulating HOXA2 via DNMT1 in vitro
lncRNA HOTAIRM1 promotes osteogenesis of hDFSCs by epigenetically regulating HOXA2 via DNMT1 in vitro
复制标题
lncRNA HOTAIRM1在体外通过DNMT1表观遗传调节HOXA2促进hDFSCs成骨
DOI：
10.1002/jcp.29695
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发表时间：
2020-04-23
影响因子：
5.6
通讯作者：
Wu Liping
中科院分区：
文献类型：
--
作者：
Chen Zhengyuan;Zheng Jinxuan;Wu Liping
牙囊可以发育成牙周组织，包括牙周膜、牙骨质和牙槽骨。牙囊干细胞(DFSCs)具有良好的多能性和成骨能力，是骨再生和牙周工程的一种很有前途的干细胞来源。然而，DFSCs介导的成骨机制仍然不清楚。我们先前的长非编码RNA(LncRNA)芯片显示，与人牙周韧带干细胞(HPDLSCs)相比，lncRNA HOTAIRM1在人牙周干细胞(HDFSCs)中的表达显著高于人牙周韧带干细胞(HPDLSCs)。LncRNA HOTAIRM1是HOXA1/2基因间隔区的反义转录本，可通过组蛋白和DNA甲基化对HOXA基因的近端和远端进行表观遗传调控。HOXA2是HOTAIRM1的靶标，对脑神经脊形核形态发生、颧弓发育和成骨起关键作用。然而，HOTAIRM1和HOXA2在牙源性干细胞中的作用仍不清楚。在这里，我们研究了这两个基因在hDFSCs中的功能和调控机制。与hPDLSCs相比，这两个基因在hDFSCs中高表达，并且在小鼠牙齿形态发生过程中，它们在牙周组织和周围牙周组织中的表达模式相似。HOTAIRM1或HOXA2基因的敲除抑制了hDFSCs的成骨分化，而过表达的HOTAIRM1则抑制了hDFSCs的增殖并促进了成骨。此外，HOTAIRM1通过机械结合HOXA2启动子区域的CpG岛，抑制了HOXA2启动子上DNMT1的整体表达和DNMT1的浓缩，导致了HOXA2的低甲基化和诱导。这些发现提示HOTAIRM1通过DNMT1表观遗传调控HOXA2促进hDFSCs的成骨。综上所述，HOTARIM1和HOXA2在hDFSCs中发挥着关键作用，HOTARIM1在HOXA簇中的调控机制被揭示。
Dental follicle (DF) can develop into periodontal tissues including periodontal ligament, cementum, and alveolar bone. Possessing superior pluripotency and osteogenic capacity, dental follicle stem cells (DFSCs) have become a promising stem cell source for bone regeneration and periodontal engineering. However, the mechanisms underlying DFSCs-mediated osteogenesis remain elusive. Our previous long noncoding RNA (lncRNA) microarray revealed that lncRNA HOTAIRM1 was significantly higher expressed in human DFSCs (hDFSCs) compared with human periodontal ligament stem cells (hPDLSCs). lncRNA HOTAIRM1, an antisense transcript of the HOXA1/2 intergenic region, can epigenetically regulate proximal and distant HOXA genes through histone and DNA methylation. HOXA2, a target of HOTAIRM1, is crucial for cranial neural crest morphogenesis, branchial arches development, and osteogenesis. However, the roles of both HOTAIRM1 and HOXA2 in odontogenic stem cells remain unknown. Here, we investigated the functions and regulatory mechanisms of these two genes in hDFSCs. Both genes were confirmed highly expressed in hDFSCs compared with hPDLSCs, and they displayed similar expression patterns in the DF and surrounding periodontium during mice tooth morphogenesis. Knockdown of either HOTAIRM1 or HOXA2 inhibited osteogenic differentiation of hDFSCs, while overexpressed HOTAIRM1 inhibited hDFSCs proliferation and promoted osteogenesis. Furthermore, HOTAIRM1 inhibited both overall DNMT1 expression and DNMT1 enrichment on HOXA2 promoter, mechanically binding to the CpG islands of the HOXA2 promoter region, leading to hypomethylation and HOXA2 induction. These findings suggested that HOTAIRM1 promoted the osteogenesis of hDFSCs by epigenetically regulating HOXA2 via DNMT1. Taken together, HOTARIM1 and HOXA2 exerted pivotal functions in hDFSCs, and the regulatory mechanism of HOTARIM1 within the HOXA cluster was uncovered.