On the Migration of the Primordial Germ Cells
On the Migration of the Primordial Germ Cells
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关于原始生殖细胞的迁移
DOI：
10.1007/978-3-642-65812-9_20
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发表时间：
1974
期刊：
影响因子：
--
通讯作者：
E. Hadorn
中科院分区：
文献类型：
--
作者：
E. Hadorn
令人惊讶的是，我们发现在许多脊椎动物和无脊椎动物中，原始生殖细胞最初并不位于中胚层性腺原基，而卵子和精子后来通过分裂和分化而产生。在许多脊椎动物中，它们首先在内胚层内可见。这意味着原始生殖细胞通常必须从它们的卵形外起源处迁移很远的距离，才能到达胚胎正在形成睾丸或卵巢的区域。因此，功能性性腺由两部分组成：一个是由个体体细胞形成的“性腺体”，另一个是注定要形成配子并开始下一代的生殖系细胞。性腺体细胞就像一个花坛，花坛的土壤滋养着生长的植物；性腺体细胞的血管为胚芽提供养分。细胞，而其他部分形成精管或成为卵泡细胞，卵子被嵌入其中。此外，在脊椎动物中，性腺细胞提供性成熟和繁殖所必需的激素。
Rather surprisingly, we find in many vertebrates and invertebrates that the primordial germ cells, from which eggs and sperm are later derived by division and differentiation, are initially not located in the mesodermal gonad primordium. In many vertebrates they are first visible within the endoderm. This means that the primordial germ cells often must migrate great distances from their extragonadal place of origin in order to reach the region where the embryo is constructing its testes or ovaries. The functional gonad, then, consists of two parts: a “gonadal soma”, formed from the somatic cells of the individual, and thegerm line cells, destined to form the gametes which will initiate the following generation. The gonadal soma resembles a flower bed, the soil of which nourishes the growing plants: the blood vessels of the gonadal soma furnish nutrients to the germ.cells, while other parts form seminiferous tubules or become the follicle cells in which the egg is embedded. In vertebrates, moreover, the cells of the gonadal soma deliver hormones necessary for sexual maturation and reproduction.