Tet1诱导猪皮肤干细胞转分化原始生殖细胞及减数分裂进入的机制

The differentiation of germ cells from stem cell became one of the hotspot in rencent years. Deriving adult stem cells, such as skin-derived stem cells (SDSCs), into germ cells will be an ideal way. Tet1 is expressed in embryonic stem cells and preimplantation embryos; it played an important role in PGC reprogramming and/or the maintenance of pluripotency of the ESC. Although several epigenetic regulators have been reported to be crucial for meiosis, the mechanisms by which Tet1 regulates the initiation of meiosis in the SDSCs through gene demethylation and how Tet1 expression contributes to primordial germ cell like cells (PGCLCs) meiosis remain poorly understood. In recent years, some articles analysis of the DNA methylation dynamics in reprogramming PGC indicates that Tet1 functions to wipe out remaining methylation, including imprinted genes, at the reprogramming stage. Stem cell derived from fetal porcine skin is a kind of stem cell that easy obtained. In the present study, applied with the technologies of RNA-Seq、microRNA、RNAi、DNA methylation and CHIP et al., investigated the influence of demethylation on dynamic changes of gene/protein expression during the period of pig SDSCs meiosis differentiate into gametes, then the role of Tet1 for meiotic initiation during PGC development should be determined. Briefly, we address function of Tet1 signal pathway for meiotic in SDSCs. We further focus on the relationship between Tet1 and gene methylation, and hope found the key upstream/downstream gene in porcine SDSCs differentiation to SLCs.

成体干细胞向生殖细胞分化是目前研究热点和难点之一，皮肤来源干细胞（SDSCs）是一种易获得且具有向生殖细胞分化潜能的成体干细胞。Tet1基因参与生殖细胞发生过程的重编程和减数分裂进入的调控，但尚无关于Tet1基因调控猪SDSCs体外分化生殖细胞及减数分裂发生的报道。本项目拟在已结题基金基础上进一步借助RNA-seq、RNAi等技术，分析Tet1基因通过调节去甲基化途径对猪SDSCs分化形成配子过程实现有效诱导，并深入研究Tet1基因通过对早期生殖细胞进行表观重编程，进而调控猪SDSCs体外向PGC分化及诱导早期生殖细胞进入减数分裂形成配子的作用途径和分子机制。本研究有望明确阐述Tet1基因通过调节生殖细胞的表观重编程，参与诱导猪SDSCs分化生殖细胞的调节机制。该项目在实践中为实现SDSCs体外诱导分化为配子搭建技术平台，在理论上可借助干细胞分化生殖细胞探索生殖细胞发生和发育的调节机制

成体干细胞向生殖细胞分化是目前研究热点和难点之一，皮肤来源干细胞（SDSCs）是一种易获得且具有向生殖细胞分化潜能的成体干细胞。Tet1基因参与生殖细胞发生过程的重编程和减数分裂进入的调控，但尚无关于Tet1基因调控猪SDSCs体外分化生殖细胞及减数分裂发生的报道。本项目在已结题基金基础上首先建立了稳定的胎猪皮肤来源干细胞(pSDSCs)向原始生殖细胞样细胞( PGCLCs)分化的体系并完善了pSDSCs向PGCLCs体外诱导分化的技术方法。明确了Tet1通过表观修饰途径调控pSDSCs 的self-renewal状态；阐明了RA通过ERK信号通路，调控转分化的PGCLCs细胞周期进而促进PGCLCs的增殖；发现YAP抑制Wnt信号通路进而保持pSDSCs的self-renewal状态；LH通过LncRNA, miRNA调控Hippo信号通路影响PGCLCs的增殖；褪黑素（MLT）通过MAPK信号通路促进SDSC向PGCLCs转分化；相关成果获2项国家发明专利授权，发表论文5篇，培养研究生5名、青年教师3名，获省级科研成果奖2项。综上，本项目在积极克服非洲猪瘟及新冠疫情等因素基础上，完成部分既定任务，明确了Tet1能通过调控表观遗传重编程进而影响pSDSCs多能性，并阐述了LPC、RA、MLT、LH等多种小分子化合物在pSDSCs形成及向PGCLCs特化过程中的调节机制，丰富了我们对pSDSCs形成过程以及pSDSCs转分化PGCLCs过程发生机制的认识。