Bentley J K, Shimomura H, Garbers D L
Cell. 1986 Apr 25;45(2):281-8. doi: 10.1016/0092-8674(86)90392-2.
Resact, a peptide obtained from eggs, causes a change in the Mr, and a loss of 32P from a plasma membrane protein identified as guanylate cyclase. Here, a resact analog (125I-[Tyr1, Ser8] resact) was synthesized and shown to bind to isolated sperm membranes. Resact, but not speract, competed with the radiolabeled ligand for binding. When membranes were prepared under appropriate conditions, guanylate cyclase remained at Mr 160,000; the incubation of membranes with gamma-32P-ATP resulted in the formation of 32P-labeled guanylate cyclase. The addition of resact to the membranes caused a shift in the Mr, a complete loss of 32P, and a 70% reduction in guanylate cyclase activity within 1 min; resact had an ED 50 at 100 nM concentration. Speract failed to cause any of these effects. This represents the first demonstration of receptor-mediated responses of isolated sperm membranes identical to those seen in the intact cell.
从卵中获得的肽类物质Resact会导致Mr发生变化，并使一种被鉴定为鸟苷酸环化酶的质膜蛋白丢失32P。在此，合成了一种Resact类似物（125I-[酪氨酸1，丝氨酸8]Resact），并证明它能与分离的精子膜结合。Resact而非speract能与放射性标记配体竞争结合。在适当条件下制备膜时，鸟苷酸环化酶的Mr保持在160,000；用γ-32P-ATP孵育膜会导致形成32P标记的鸟苷酸环化酶。向膜中添加Resact会导致Mr发生变化、32P完全丢失，且在1分钟内鸟苷酸环化酶活性降低70%；Resact在100 nM浓度下的半数有效剂量（ED50）为该值。Speract未能引起这些效应中的任何一种。这是首次证明分离的精子膜的受体介导反应与完整细胞中所见的反应相同。
