Reprogramming towards a germline stem cell fate

项目摘要 生殖系细胞永生是所有有性繁殖物种延续的基础。 最近的研究发现了生殖系和体细胞之间相互转换的常见例子 命运，暗示着生殖系和胞体之间的可塑性，而不是严格的二分法。在……里面 成年后，雄配子的产生是由生殖系干细胞(GSC)分裂驱动的。在我的 博士后工作，我建议使用果蝇强大的易驯服系统 确定雄性黑猩猩生殖系不朽命运的必要因素。此外 到经历正常的自我更新和分化，GSCs可以通过 精原细胞的去分化，并可通过强迫分化为生殖细胞而丧失 细胞和转分化为胞体。首先，在中国的睾丸细胞上使用单细胞RNA测序 哪个生殖系正在经历去分化，我将重建血统过渡到 从分化的细胞中识别形成GSC的潜在基因，包括生殖细胞- 自主因素和非自主信号因素。我将使用这两个工具验证这些数据 基因在体内的表达特征和功能分析。接下来，我将描述一下 GSCs向体细胞转分化所需的转录变化，鉴定 维持生殖系同一性的成分。最后，我将利用因素的发现 参与a)分化细胞产生GSC，b)GSC的丧失 导致体细胞形成的特性，以便开发一种新的诱导模型 体细胞重新编程到生殖系的命运。这项工作将极大地加深我们对 使细胞永生的因素，并将有助于开发治疗 多样的人类疾病。

Project Summary Germline cellular immortality underlies the continuation of all sexually reproducing species. Recent work has identified frequent examples of interconversion between germline and somatic fates, suggesting plasticity, rather than a strict dichotomy, between germline and soma. In adults, production of male gametes is driven by germline stem cell (GSC) division. In my postdoctoral work, I propose to use the powerfully tractable system of the Drosophila melanogaster male germline to identify necessary factors of immortal germline fate. In addition to undergoing normal self-renewal and differentiation, GSCs can be generated through dedifferentiation of spermatogonia, and can be lost through both forced differentiation to germ cells and transdifferentiation to soma. First, using single-cell RNA sequencing on testes cells in which the germline is undergoing dedifferentiation, I will reconstruct lineage transitions to identify genes underlying GSC formation from a differentiated cell, including both germline cell- autonomous factors and non-autonomous signaling factors. I will validate these data using both in vivo expression characterization and assays of gene function. Next, I will describe the transcriptional changes necessary for transdifferentiation of GSCs to somatic cells, identifying the components that maintain germline identity. Finally, I will leverage discovery of factors involved in both a) the creation of GSCs from differentiating cells, and b) the loss of GSC identity that results in somatic cell formation, in order to develop a novel model for inducible somatic reprogramming to a germline fate. This work will significantly further our understanding of the factors that confer cellular immortality, and will aid in the development of therapies for diverse human diseases.