Swann K
MRC Experimental Embryology and Teratology Unit, St George's Hospital Medical School, London, UK.
Development. 1990 Dec;110(4):1295-302. doi: 10.1242/dev.110.4.1295.
Microinjection of cytosolic sperm extracts into unfertilized golden hamster eggs caused a series of increases in cytoplasmic free calcium, Ca2+i, and membrane hyperpolarizing responses, HRs. These HRs and Ca2+i transients are similar to those seen during in vitro fertilization of hamster eggs. The sperm factor that is responsible for causing these effects appears to be of high molecular weight and protein based. Injection of sperm factor activated eggs and mimicked fertilization in causing repetitive HRs in the presence of phorbol esters and in sensitizing the egg to calcium-induced calcium release. Since these effects cannot be mimicked by injecting G-protein agonists or calcium-containing solutions, it seems unlikely that a receptor-G-protein signalling system is involved at fertilization. These data instead suggest a novel signal transduction system operates during mammalian fertilization in which a protein factor is transferred from the sperm into the egg cytoplasm after gamete membrane fusion.
将胞质精子提取物显微注射到未受精的金黄地鼠卵中会引起一系列细胞质游离钙（Ca2+i）增加以及膜超极化反应（HRs）。这些HRs和Ca2+i瞬变与在仓鼠卵体外受精过程中观察到的相似。负责引起这些效应的精子因子似乎是高分子量且基于蛋白质的。注射精子因子可激活卵子，并在佛波酯存在的情况下模拟受精引起重复性HRs，还能使卵子对钙诱导的钙释放敏感。由于注射G蛋白激动剂或含钙溶液无法模拟这些效应，受精过程似乎不太可能涉及受体 - G蛋白信号系统。这些数据反而表明，在哺乳动物受精过程中存在一种新的信号转导系统，其中一种蛋白质因子在配子膜融合后从精子转移到卵细胞质中。
