Rubinstein Eric, Ziyyat Ahmed, Wolf Jean-Philippe, Le Naour François, Boucheix Claude
Inserm, U602, Villejuif, France.
Semin Cell Dev Biol. 2006 Apr;17(2):254-63. doi: 10.1016/j.semcdb.2006.02.012. Epub 2006 Mar 2.
Fertilization includes a series of cellular interactions culminating with the fusion of gamete membranes, creating a zygote. Two ADAM proteins present on sperm, fertilin beta and cyritestin, drew much attention. However, gene deletion in mice showed that fusion can happen in their absence. The presence of the integrin alpha6beta1 on egg, a putative fertilin beta receptor, is also dispensable. In contrast, sperm lacking Izumo, a molecule with a single Ig domain, are unable to fuse. On the egg side, a role for GPI-anchored molecules has been shown, and in mice lacking both tetraspanins CD9 and CD81 fertilization is completely blocked.
受精过程包括一系列细胞间相互作用，最终以配子膜融合形成受精卵而告终。精子上存在的两种ADAM蛋白，受精素β和cyritestin，备受关注。然而，小鼠基因敲除实验表明，即便没有它们，融合仍可发生。卵子上存在的整合素α6β1，一种假定的受精素β受体，也并非不可或缺。相比之下，缺乏Izumo（一种具有单个Ig结构域的分子）的精子无法发生融合。在卵子方面，已证明糖基磷脂酰肌醇锚定分子发挥了作用，而且在同时缺乏四跨膜蛋白CD9和CD81的小鼠中，受精完全受阻。
