Ikenishi K, Okuda T, Nakazato S
Dev Biol. 1984 May;103(1):258-62. doi: 10.1016/0012-1606(84)90027-7.
A single blastomere containing the "germ plasm" of 32-cell stage Xenopus embryos was cultured with [3H]thymidine until the control embryos developed to the neurula stage. The explants, showing a spherical mass in which the nuclei of all cells were labeled, were implanted into the prospective place of presumptive primordial germ cells (pPGCs) in the endodermal cell mass of unlabeled host embryos of the neurula stage. Labeled PGCs as well as unlabeled, host PGCs were found in the genital ridges of experimental tadpoles. This indicates that the precursor of germ cells, corresponding to pPGCs in normal embryos of the neurula stage, in the explants migrated to genital ridges just at the right moment to become PGCs, and suggests that the developmental process progressed normally, even in the explants, as far as the differentiation of pPGCs is concerned.
将含有32细胞期非洲爪蟾胚胎“生殖质”的单个卵裂球与[3H]胸腺嘧啶核苷一起培养，直到对照胚胎发育到神经胚阶段。这些外植体呈现出一个球形团块，其中所有细胞的细胞核都被标记，然后将其植入神经胚阶段未标记宿主胚胎内胚层细胞团中预定原始生殖细胞（pPGC）的预期位置。在实验蝌蚪的生殖嵴中发现了标记的PGC以及未标记的宿主PGC。这表明外植体中生殖细胞的前体，相当于神经胚阶段正常胚胎中的pPGC，在恰当的时候迁移到生殖嵴并成为PGC，这表明就pPGC的分化而言，即使在外植体中，发育过程也正常进行。
