Molecular mechanism of natural pluripotency establishment in the early mouse embryo based on single-cell gene expression profile

了解导致体内自然多能性建立的分子机制对于干细胞生物学在再生医学中的有效应用至关重要。本项目的主要目的是了解小鼠囊胚多能性内细胞团形成的分子程序，这也将阐明胚胎干细胞的分子特性。本项目旨在将单细胞基因表达谱应用于小鼠着床前胚胎，以全面表征导致多能谱系分离的分子特征。在过去的两年中，我们成功地建立了内细胞群细胞的方法和分子特征。这导致我们i)鉴定了内细胞群中两个不同群体的分子特征，外胚层和原始内胚层；Ii)识别最早可能的标记，从而确定谱系分离的潜在关键因素；Iii)表征在早期发育阶段突出的随机基因表达。在这个提议中，我们将采用同样的成功策略来表征内细胞群和滋养外胚层细胞系之间的分离，这种分离可能发生在早期发育阶段，桑葚胚。总之，这将允许全面表征关键分子和导致体内基态初始多能性形成的潜在机制。

Understanding of the molecular mechanism leading to establishment of natural pluripotency in vivo is crucial for the efficient application of stem cell biology to regenerative medicine. The principal aim of this project is to understand the molecular program underlying formation of the pluripotent inner cell mass in the mouse blastocyst, which will also elucidate molecular properties of embryonic stem cells. This project focuses on applying single-cell gene expression profiling to the mouse pre-implantation embryo, in order to comprehensively characterize molecular signature leading to the pluripotent lineage segregation. In the last two years, we have successfully established the methodologies and characterized molecular signatures within the inner cell mass cells. This led us to i) identify the molecular signature characteristic to two distinct populations in the inner cell mass, epiblast and primitive endoderm; ii) identify the earliest possible markers, thus potential key players, for the lineage segregation; iii) characterize stochastic gene expression prominent in the early developmental stages. In this proposal, we will apply the same successful strategy to characterize the segregation between the inner cell mass and trophectoderm cell lineages, likely taking place in the earlier developmental stage, morula. Altogether this will allow comprehensive characterization of key molecules and the underlying mechanism leading to the formation of ground state naive pluripotency in vivo.