Nanog is a homeodomain transcription factor that plays a prominent role in maintaining the pluripotency and self-renewal capacity of embryonic stem cells (ESCs) in mammals. Medaka Nanog is necessary for S-phase transition and proliferation during embryonic development. However, whether Nanog regulates the proliferation of primordial germ cells (PGCs) during embryonic development has not yet been investigated. In this study, we identified the homologue of the mammalian Nanog gene in zebrafish (zNanog). The expression of both zNanog mRNA and protein was demonstrated in the spermatogonia (male germ stem cells) of the testis and the early oocytes of the ovary. During the embryonic development, zNanog mRNA is expressed in the cytoplasm of PGCs, and its protein is localized to the PGC nuclei. We also found that zNanog depletion using morpholinos resulted in the increases and aberrant localization of PGCs in the zebrafish embryos from the sphere stage to the 50% epiboly stage. These data indicated that zNanog inhibits the PGCs proliferation in early embryonic development of zebrafish.

中文翻译：

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减少斑马鱼Nanog增加早期胚胎发育过程中的原始生殖细胞。

Nanog是一个同源结构域转录因子，在维持哺乳动物胚胎干细胞（ESC）的多能性和自我更新能力方面发挥着重要作用。Medaka Nanog对于胚胎发育过程中的S期过渡和增殖是必不可少的。但是，尚未研究Nanog是否在胚胎发育过程中调节原始生殖细胞（PGCs）的增殖。在这项研究中，我们确定了斑马鱼（zNanog）中的哺乳动物Nanog基因的同源物。在睾丸的精原细胞（雄性生殖干细胞）和卵巢的早期卵母细胞中证实了zNanog mRNA和蛋白的表达。在胚胎发育过程中，zNanog mRNA在PGC的细胞质中表达，其蛋白质定位在PGC核中。我们还发现，使用吗啉代糖耗竭的zNanog导致斑马鱼胚胎中从球形到50％外延期的PGC的增加和异常定位。这些数据表明zNanog在斑马鱼的早期胚胎发育中抑制了PGC的增殖。