Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA.
Mol Reprod Dev. 2010 Jan;77(1):3-18. doi: 10.1002/mrd.21091.
Germ cells occupy a unique position in animal reproduction, development, and evolution. In sexually reproducing animals, only they can produce gametes and contribute genetically to subsequent generations. Nonetheless, germ line specification during embryogenesis is conceptually the same as the specification of any somatic cell type: germ cells must activate a specific gene regulatory network in order to differentiate and go through gametogenesis. While many genes with critical roles in the germ line have been characterized with respect to expression pattern and genetic interactions, it is the molecular interactions of the relevant gene products that are ultimately responsible for germ cell differentiation. This review summarizes the current state of knowledge on the molecular functions and biochemical connections between germ line gene products. We find that homologous genes often interact physically with the same conserved molecular partners across the metazoans. We also point out cases of nonhomologous genes from different species whose gene products play analogous biological roles in the germ line. We suggest a preliminary molecular definition of an ancestral "pluripotency module" that could have been modified during metazoan evolution to become specific to the germ line.
生殖细胞在动物生殖、发育和进化中占据独特的地位。在有性繁殖的动物中，只有它们能够产生配子，并为后代遗传做出贡献。然而，胚胎发生过程中的生殖系特化在概念上与任何体细胞类型的特化相同：生殖细胞必须激活特定的基因调控网络，才能进行分化并经历配子发生。虽然许多在生殖系中具有关键作用的基因在表达模式和遗传相互作用方面已经得到了描述，但最终负责生殖细胞分化的是相关基因产物的分子相互作用。这篇综述总结了目前关于生殖系基因产物的分子功能和生化联系的知识状态。我们发现，同源基因通常与后生动物中相同的保守分子伴侣发生物理相互作用。我们还指出了来自不同物种的非同源基因的情况，它们的基因产物在生殖系中发挥类似的生物学作用。我们提出了一个初步的分子定义，即祖先的“多能性模块”，它可能在后生动物进化过程中被修饰，成为生殖系特有的。
