转录因子Nanog对小鼠原始生殖细胞发育的影响机制研究

项目名称： 转录因子Nanog对小鼠原始生殖细胞发育的影响机制研究

项目编号： No.31071055

项目类型： 面上项目

立项/批准年度： 2011

项目学科： 轻工业、手工业

项目作者： 王璐

作者单位： 重庆医科大学

项目金额： 8万元

中文摘要： 课题探讨多能性干细胞核心调控基因Nanog对原始生殖细胞发育的影响机制， Nanog在小鼠原始生殖细胞发育过程中的不同时间和空间上的表达分布，小鼠性腺分化前后原始生殖细胞中Nanog的表达变化；RNA干扰抑制Nanog表达后对原始生殖细胞增殖未分化状态、凋亡以及触发向生殖细胞分化的影响。结果表明：1、Nanog阳性表达于尿囊、后肠及背肠系膜、 生殖嵴的原始生殖细胞中。2、小鼠原始生殖细胞到达生殖腺后，伴随原始生殖细胞向生殖细胞分化，Nanog的表达降低。3、分离原始生殖细胞，成功进行体外胚胎生殖细胞（EG细胞）培养。4、RNA干扰抑制Nanog表达后，EG细胞维持未分化能力降低，增殖抑制，减数分裂相关基因表达上调；同时伴随EG细胞的凋亡增加。研究提示多能干细胞核心调控因子Nanog是胚胎体内维持原始生殖细胞增殖未分化状态、抑制凋亡的关键因子；原始生殖细胞到达生殖腺后开始生殖母细胞化进行减数分裂，可能与Nanog表达下调相关。课题从体内体外两条途径着手，对原始生殖细胞和EG细胞的自我更新、分化机制进行有益的探索，为发育生物学、生殖医学以及干细胞生物学领域相关研究提供实验依据及思路。

中文关键词： 原始生殖细胞；增殖；凋亡；分化；Nanog

英文摘要： This study focused on the effect of the pluripotent stem cell core gene Nanog on the development of primordial germ cells. Three pionts were discussed in the study as followed. The tmporal and spartial expression of Nanog in deveoping primordial germ cells;the variance of Nanog protein expression between primordial germ cells before and after gonads specification; the effct of targeted RNA interference of Nanog in embryonic germ cells on their proliferation, maintainance of undifferentiation, apoptosis,and triggering on differntiation towards gonacytes direction. Results showed positive expression of Nanog located in the primordials germ cells of mouse allantois, hindgut, dorsal mesentory and genital ridge. Nanog protein expression decreased concomitantly with the differentiation of primordial germ cells in vivo towards gonocytes after which arrived at gonads.The isolated mouse primordial germ cells could be successfully cultured according to embryonic germ cells (EG cells) criterion in vitro.Afer RNA interference of Nanog, the capacity of EG cells undifferentiation maintainance declined, proliferation of EG cells was suppressed, and some meiotic relevant gene expression upregulated. The apoptosis of EG cells could also be observed. The results indicate that the pluripotent stem cell core gene Nanog is the key factor of maintaining primordial germ cell undifferentiated and inhibiting its apoptosis during embryonic development. The event that primordial germ cells differentiate towards gonocytes after they arrive at gonods may be correlated with the downregulated Nanog expression.This study will be a good exploration on the self-renewal and differntiation mechanism of primordial germ cells in vivo and EG cells in vitro, thus provide experimental proof and thinking way for biology of development, reproduction and stem cells.

英文关键词： primordial germ cell; proliferation; apoptosis; specification; Nanog