Pepling M E, Spradling A C
Howard Hughes Medical Institute Research Laboratories, Department of Embryology, Carnegie Institution of Washington, Baltimore, MD 21210, USA.
Development. 1998 Sep;125(17):3323-8. doi: 10.1242/dev.125.17.3323.
Oocytes from many invertebrates initiate development within distinctive cysts of interconnected cells, which are formed through synchronous divisions of a progenitor cell. Recently, processes underlying cyst formation have been extensively characterized at the molecular level in Drosophila. Defects in this process cause sterility in female flies. Early female mouse germ cells are organized as cell clusters as well, but it is uncertain whether these groups are similar to the cysts of invertebrates. We find that mouse germ cells are connected by intercellular bridges in the ovaries of 11.5 to 17.5 days postcoitum embryos; microtubules and organelles have been observed within these bridges. Confocal microscopy shows that cells within mouse clusters divide synchronously and frequently correspond in number to powers of two. Thus, female mouse germ cell clusters exhibit key characteristics of invertebrate germline cysts indicating that the process of germline cyst formation is conserved in the mouse.
许多无脊椎动物的卵母细胞在由相互连接的细胞组成的独特囊肿内开始发育，这些囊肿是通过祖细胞的同步分裂形成的。最近，果蝇中囊肿形成的潜在过程在分子水平上得到了广泛的表征。这一过程中的缺陷会导致雌性果蝇不育。早期雌性小鼠生殖细胞也被组织成细胞簇，但尚不确定这些细胞簇是否类似于无脊椎动物的囊肿。我们发现，在妊娠11.5至17.5天的胚胎卵巢中，小鼠生殖细胞通过细胞间桥相连；在这些桥内观察到了微管和细胞器。共聚焦显微镜显示，小鼠细胞簇内的细胞同步分裂，且数量常常与2的幂次方相对应。因此，雌性小鼠生殖细胞簇表现出无脊椎动物种系囊肿的关键特征，表明种系囊肿形成过程在小鼠中是保守的。
