RNA剪接蛋白PRPF8调控人胚胎干细胞自我更新和分化的作用及机制研究

Human embryonic stem cells (hESC), derived from the inner cell mass of the blastocysts of human embryos have two unique characteristics, unlimited self-renewal in vitro and pluripotency. Despite the extensive studies on the regulatory role of the core transcription factors and the signaling-pathway in hESC, post-transcriptional regulation of RNAs in hESC is largely unknown. Our preliminary data indicate that pre-mRNA processing splicing factor 8 (PRPF8) is essential for the self-renewal of hESC. It is possible that PRPF8 regulates the p53 signaling pathway through the post-transcriptional regulation of RNA splicing processing. In this project, we plan to further verify the function of PRPF8 in the maintenance of hESC self-renewal and regulation of differentiation; identify key downstream targets of PRPF8 and the manner by which it acts; find key genes involved in p53 signaling pathway regulated by PRPF8; elucidate the molecular mechanism by which PRPF8 regulates gene expression. Through completing this study, we hope to reveal a pathway important for hESC self-renewal controlled by PRPF8 for post-transcriptional regulation of p53 signaling pathway. This study will help to understand the underlying mechanism of the regulation network for hESC self-renewal and to guide directed differentiation of hESC.

人胚胎干细胞（hESC）是来源于人囊胚期内细胞团细胞，具有在体外无限自我更新的能力和分化的多能性。目前，关于hESC调控机制的研究主要集中在转录因子与细胞外信号通路。关于RNA转录后调控以及p53信号通路在调控hESC自我更新与分化的研究非常有限。申请人课题组前期研究发现RNA剪接复合体成员PRPF8对维持hESC自我更新具有重要作用，并有可能是通过调控p53信号通路的相关基因表达来行使其功能。本项目拟1）进一步确定PRPF8在hESC自我更新维持与分化调控中的作用；2) 发现PRPF8在hESC调控的关键靶基因及作用方式；3) 找到受PRPF8调控的p53相关基因；4) 揭示PRPF8调控基因表达的分子机制。通过本项目的实施希望揭示以PRPF8为主导，在转录后水平调节p53信号通路活性，对hESC自我更新维持的调控机制, 从而完善hESC自我更新的调控网络和为hESC定向分化提供指导。