STRUCTURE & FUNCTION OF THE EPIDIDYMIS AND VAS DEFERENS

需要资金来开展蛋白质功能方面的项目 属于雄性生殖道中的Crisp超家族。三根脆皮 基因以器官特有的方式编码蛋白质：CRISP-2是睾丸- Crisp-3是颌下腺特异的，而Crisp-1是 主要在附睾部表达。在哺乳动物身上发现了脆性基因 像大鼠、豚鼠、小鼠和人类一样多种多样，所以必须有一个 在表达它们的器官中的重要功能。 CRISP-1蛋白是由附睾合成和分泌的 上皮细胞，然后以区域特异性的方式与精子结合 在老鼠身上。既松散又紧密结合的蛋白D定位于 顶体和顶体上的质膜上的精子的头部 已经被证明在受精过程中起到了作用。蛋白E结合在一起 特别是尾部的质膜，也参与了 受精。蛋白质D和E与 贺尔托明(一种唾液腺毒素，可阻断兰尼定受体) 以及一些昆虫和蛇毒蛋白，这些蛋白能够 调节离子通道。我们假设蛋白质D和E的功能 调节精子离子流量，尤其是钙离子。在第一个 具体目的：探讨Crisp-1在精卵融合中的作用。 在第二个目标中，我们探索它们在获能中的作用和 顶体反应，这两个过程都需要大量的离子通量。 最后，在最后一个具体目标中，我们解决了 蛋白D和E与精子结合的机制(S) 附睾症。我们假设结构域局部化的信号 驻留在分子的NH2末端和羧基末端， 在发现16种半胱氨酸中的14种时，提供质膜 结合结构域。这些研究将对以下方面提供重要的知识 一组潜在的重要蛋白质在 附睾的生理学和受精过程。

Funds are requested to carry out projects on the function of proteins of the Crisp superfamily in the male reproductive tract. Three Crisp genes encode proteins in an organ-specific manner: Crisp-2 is testis- specific, Crisp-3 is submandibular gland-specific and Crisp-1 is expressed primarily in the epididymis. Crisp genes are found in mammals as diverse as rats, guinea pigs, mice and humans and so must have an important function in the organs within which they are expressed. Crisp-1 proteins are synthesized and secreted by the epididymal epithelium and subsequently bind to sperm in a domain-specific manner in rats. Protein D, which binds both loosely and tightly, localizes to the head of the sperm on the plasma membrane overlying the acrosome and has been shown to play a role in fertilization. Protein E binds specifically to plasma membrane of the tail, and also participates in fertilization. Proteins D and E have significant homology to helothermine (a salivary gland toxin that blocks ryanodine receptors) and to a number of insect and snake venom proteins that are capable of regulating ion channels. We hypothesize that proteins D and E function to regulate sperm ion fluxes, particularly calcium. In the first specific aim we explore the roles of Crisp-1 during sperm-egg fusion. In the second aim, we explore their role in capacitation and the acrosome reaction, both processes that require large ion fluxes. Finally, in the last specific aim we address the question of mechanism(s) that mediate binding of protein D and E to sperm in the epididymis. We hypothesize that the signal for domain localization resides in the NH2 terminus of the molecule and the carboxyl terminus, where 14 of the 16 cysteines are found, provides the plasma membrane binding domain. These studies will contribute significant knowledge on the role of a potentially important group of proteins both in the physiology of the epididymis and in fertilization.