Baughman Joshua M, Geijsen Niels
Graduate Program of Biological and Biomedical Sciences, Harvard Medical School, Boston, MA 02115, USA.
Ann N Y Acad Sci. 2005 Dec;1061:33-40. doi: 10.1196/annals.1336.005.
Primordial germ cells comprise a privileged cellular class within the embryo charged with the elite task of maintaining species longevity. While in lower organisms germ-cell fate is determined by the allocation of germ plasm, mammalian germ-line differentiation requires extracellular signals that converge upon the proximal epiblast. Studies using mutant mice or explanted embryos have identified some of the factors controlling primordial germ-cell specification, such as members of the BMP family, but considerable gaps still exist in our understanding of the complete signaling network. Comprehensive investigations of mammalian germ-line specification have been hampered by the inaccessibility of this cell population in the early embryo. Recently, however, several labs including our own have derived primordial germ cells from embryonic stem cells in vitro, thus providing a powerful new technique for the study of germ cells. In this review the different methods used for the in vitro generation of germ cells and how these techniques may be improved and applied to further advance our knowledge of germ-cell biology are discussed.
原始生殖细胞是胚胎内一类特殊的细胞，肩负着维持物种延续的重要使命。在低等生物中，生殖细胞命运由种质分配决定，而哺乳动物生殖系的分化则需要细胞外信号汇聚到近上胚层。利用突变小鼠或体外培养胚胎进行的研究已确定了一些控制原始生殖细胞特化的因子，如骨形态发生蛋白（BMP）家族成员，但我们对完整信号网络的理解仍存在相当大的差距。早期胚胎中该细胞群体难以获取，阻碍了对哺乳动物生殖系特化的全面研究。然而，最近包括我们实验室在内的几个实验室已在体外从胚胎干细胞中获得了原始生殖细胞，从而为生殖细胞研究提供了一项强大的新技术。本文综述了用于体外生成生殖细胞的不同方法，以及如何改进这些技术并应用它们来进一步增进我们对生殖细胞生物学的认识。
