小鼠iPS细胞体外自发性分化及神经定向分化中基因表达谱的研究

目的:研究小鼠诱导多能干细胞(i PS细胞)在体外自发性分化和神经定向分化过程中的基因表达谱的特性。方法:在体外将i PS细胞分别进行形成类胚胎小体后自发性分化及成骨蛋白抑制剂Noggin诱导神经定向分化后,通过实时荧光定量PCR(q PCR)测定在分化过程中i PS细胞分化相关基因表达的变化。结果:i PS细胞形成类胚胎小体后胚胎外胚层标志基因(GFAP,Map2和Tu J1)及内胚层标记基因(Foxa2,GATA4和Sox17)的表达随分化而迅速增加,但中胚层标记基因(Bmp4,BRA,FGF5)表达水平变化不明显。在神经定向分化过程中,i PS细胞的神经标志物基因(Map2,Neu N,Tu J1和Sox1)及线粒体相关基因(12s,ND3,ND5,ND6、Cytb和Cox1)的表达都逐渐增加,且两者具有相同的增长趋势。结论:在自发性分化过程中小鼠i PS细胞具有自发向外胚层和内胚层分化的趋势;在神经定向分化过程中,i PS细胞的线粒体相关基因表达随着分化表达逐渐增加,并与神经细胞标记基因具有正相关性,表明线粒体的功能在i PS细胞神经定向分化中发挥重要作用。

Gene expression profiling in mouse iPS cell during spontaneous and neural lineage differentiation

Objective:To study the characteristics of gene expression profiles of mouse induced pluripotent stem cells (iPS cells) in the process of spontaneous and neural lineage differentiation.Methods:In vitro,iPS cells were subjected to spontaneous differentiation or Noggin inducing neural differentiation.Accurate assessment of these differentiation-related gene expression changes by Real-time quantitative PCR (qPCR).Results:The expression of embryonic ectoderm marker genes (GFAP,Map2 and TuJ1) and endoderm marker genes (Foxa2,GATA4 and Sox17) increased rapidly during the spontaneous differentiation of iPS cell,but the changes in expression levels of mesoderm marker gene (Bmp4,BRA,FGF5) was not obvious.The neural marker genes (Map2,NeuN,TuJ1 and Sox1) and mitochondrial genes (12s,ND3 ND5,ND6,Cytb and Cox1) exhibit the same pattern of expression and increased gradually during neural differentiation.Conclusion:The iPS cells have a tendency to spontaneously differentiate into ectoderm and endoderm.During neural differentiation,the increase in neural marker genes expression corresponded to the increase in mitochondrial gene expressions,which indicated that mitochondrial function plays a crucial role in neural differentiation on iPS cells.