The role of the PGC master regulators Blimp1, Prdm14 and Tfap2c on the licensing of germ cells - control of pluripotency and channeling into unipotency

生殖细胞在该物种中繁殖。在哺乳动物中，生殖细胞被指定为早期胚胎中的原始生殖细胞(PGC)。它们迁移到性腺，在那里进一步分化形成卵子和精子。在这个过程中，上胚层的多能细胞产生潜伏的多能细胞(PGC)，这些细胞被引导成单能细胞(卵子和精子)。对潜在的多能性的控制和向单能性的转化是一个鲜为人知的过程。事实上，分子级联的扰动会导致不育和/或生殖细胞肿瘤，这表明需要对这一过程有更多的了解。我们建议分析过表达生殖细胞特异性基因Tfap2c、Blimp1和PRDM14的功能性转基因小鼠的生殖细胞特异性获得。我们将分析发育过程中不同时期的性腺，并将PGCs带入培养中，以获得胚胎生殖细胞。我们设想转基因可以延长EG细胞的衍生时间(野生型直到E10.5天)，这将表明导管转化为单能的过程中发生了扰动。这种缺陷可能会导致生殖细胞肿瘤的发展，在人类情况下，生殖细胞肿瘤的特点是Tfap2c和BLIMP1的持续表达。最近的一项研究表明，PRDM14与生殖细胞肿瘤有关。我们假设，每一种转基因都会引起基因表达的特定变化，从而导致不同类型的肿瘤。此外，我们将把EG细胞移植到皮肤下，并监测肿瘤的形成。这将与睾丸中的肿瘤发生进行比较，并将允许对肿瘤微环境(躯体与睾丸)进行比较。这份申请是基于最近一次休假的印象。这些实验可能看起来雄心勃勃，但申请者将与D.Page(麻省理工学院)教授的前休假实验室在生殖细胞开发方面进行合作，并与D.DeRooij教授(此时也是Page实验室的客座科学家)合作，以实现所述的所有目标。

Germ cells propagate the species. In mammals, germ cells are specified as primpordial germ cells (PGCs) in the early embryo. They migrate to the gonads where they differentiate further to form egg and sperm. In this process, pluripotent cells of the epiblast give rise to latent pluripotent cells (PGCs), which are channeled, into unipotency (egg and sperm). The control of the latent pluripotency and the channeling into unipotency is a poorly understood process. The fact that perturbations of the molecular cascades lead to sterility and/or germ cell tumors demonstrates that more knowledge about this process is mandatory.We propose to analyze germ cell specific gain of function transgenic mice overexpressing the germ cell specifiying genes Tfap2c, Blimp1 and Prdm14. We will analyze the gonads at various times during development and will bring PGCs in culture to derive embryonic germ cells. We envision that the transgenes allow for prolonged derivation of EG cells (in wildtype only up to day E 10.5), which will indicate a perturbation in canalization into unipotency. This defect might lead to the development of germ cell tumors, which, in the human situation are hallmarked by persistent expression of TFAP2C and BLIMP1. PRDM14 has been implicated in germ cell tumors by a GWAS study recently. We hypothesize, that each transgene will elicit a rather specific change in gene expression leading to a different type of tumor. In addition, we will transplant the EG-cells under the skin and monitor tumor formation. This will be compared to the tumorigenesis in the testes and will allow a comparison of the tumor-microenvironment (somatic vs. testes). The application is based on the impression of a recent sabbatical. The experiments might appear ambitious, but the applicant will cooperate with the ex-sabbatical lab of Prof. Dr. D. Page (MIT) in terms of germ cell development, and with Prof. Dr. D. deRooij (who was also visiting scientist at the Page lab at this time) to achieve all goals described.