线虫(Caenorhabditis elegans)受精卵中细胞极性的建立

The establishment of cell polarity in Caenorhabditis elegans zygotes

早期线虫胚胎提供了一个研究发育过程的极佳模型。线虫胚胎的第一次分裂是不对称的,产生的两个子细胞在尺度的大小和发育命运上均有不同,而这些不同是由第一次有丝分裂周期中胞质决定子的不均匀分布造成的。通常相信,在受精过程中,精子所携带的中心体介导了对极性建成至关重要的胞质流动的产生。同时,细胞骨架成分被认为参与了胞质成分的定位事件。关于par基因的研究目前进展迅速,大多数par基因的突变都导致了线虫早期胚胎分裂不对称性的丧失。

Early Caenorhabditis elegans embryos provide an excellent model for the study of developmental processes. The first division of the C, elegans embryo is asymmetric, generating two daughter cells unequal in size and developmental fate. And the differences are determined by asymmetric localization of cytoplasmic determinants during the first mitotic cell cycle.It was thought that during the fertilization, the centrosome of sperm directed the process of cytoplasmic flow ,which is crucial to the establishment of polarity in C. elegans. Cytoskeletal compenents are also required to the localization of cytoplasmic components. Studies on par gene progressed at a rapid rate. Mutations of most par gene result in the loss of asymmetry of the C.elegans early embryos.