长链非编码RNA Gm15055在小鼠胚胎干细胞向神经元分化过程中的功能和机制研究

The self-renewal and totipotent of embryonic stem cells(ESCs) raise great potential for cell-replacement therapies of neurodegenerative diseases.In order to enhance the efficiency and security of neuronal differentiation from ESCs, the mechanisms are still to be uncovered. We have found that in mouse ESCs long noncoding RNA(lncRNA) Gm15055’s transcript and potential enhancer within its gene locus could cooperatively regulate Hoxa genes which are essential for cell fate determinaton during development, moreover, during neuronal differentiation of Gm15055 knockout mESCs the neuronal marker gene’s expression level and the general proportion of oligodendrocyte cells are all increased. However, it’s still unknown which and how Gm15055 could affect specific types of neurons’ formation and at which stages during neuronal differentiation. In this study we will investigate lncRNA Gm15055’s role in neuronal differentiation by using Gm15055 knockout mice and ESCs. We will find out which types of neurons could be affected by Gm15055 and we will also investigate the molecular mechanism that Gm15055 regulates neuronal differentiation. Our study will find new mechanism of neuronal differentiation regulation and will help to optimize the differentiation procedure of in vitro neuronal differentiation of ESCs.

通过胚胎干细胞自我更新能力和分化全能性形成无限特定的神经元为治疗神经退行性疾病提供了巨大潜力。为了提高胚胎干细胞向特定神经元分化的效率和安全性，其分化机制还有待进一步研究。我们发现长链非编码RNA Gm15055转录产物与其基因座内的增强子元件协同调控小鼠胚胎干细胞中的Hoxa基因簇表达，另外Gm15055敲除的小鼠胚胎干细胞向神经元非定向诱导分化过程中神经元标志基因表达水平和少突细胞比例都出现上调。但是在胚胎干细胞向神经元分化过程中Gm15055在哪个阶段、通过何种方式、影响哪种神经元发生还并不清楚。本研究拟应用Gm15055基因敲除小鼠和胚胎干细胞，明确Gm15055对特定神经元发生的影响，并通过分子生物学方法确定Gm15055调控神经元分化的下游靶基因从而阐明其机制。本研究将帮助弄清胚胎干细胞向神经元分化的调控机制并为体外胚胎干细胞向特定神经元分化方法的优化提供帮助。

胚胎干细胞的自我更新能力和分化全能性为使用体外分化神经元治疗神经退行性疾病提供了巨大潜能。为提高胚胎干细胞向特定神经元分化的效率和安全性，其分化机制还有待进一步研究。本项目研究了长链非编码RNA Gm15055在小鼠胚胎干细胞向神经元分化过程中的功能。本项目使用Gm15055基因敲除胚胎干细胞和小鼠，使用多种分化模型研究敲除Gm15055对多巴胺神经元分化和非定向神经元分化的影响。我们的研究结果显示敲除Gm15055能显著降低多巴胺神经元分化过程中的神经元标志分子基因表达。在拟胚体和维甲酸诱导的非定向神经元分化过程中，敲除Gm15055能促进胚胎干细胞的分化，促进神经外胚层分化和神经元前体细胞的形成。我们的结果提示长链非编码RNA Gm15055可能在神经元分化的早期通过维持细胞多能性调节细胞分化能力，敲除Gm15055基因将会促进神经元前体的形成。