STRUCTURAL BASIS FOR DIFFERENCES BETWEEN ELH AND ECG

马的促性腺激素，ELH和心电，结合相同的受体， 同时显示促黄体生成素和促卵泡刺激素活性，具有相同的氨基酸 它们的糖基化模式有很大的不同。 因此，在体内和体外观察到它们之间的所有功能差异 在体外只是由于糖基化。心电信号与心电的亲和力 马的促黄体生成素受体比促黄体生成素少57-75倍。半衰期 循环中的心电图者大于ELH者。有一种广泛的 心电图学在促进卵泡发育和促进卵泡发育中的应用 超数排卵本身是目的，也是生产的一种手段 大量的动物用于其他研究。 杂交激素是由不同组合的完整 ASN56脱糖基化ELHα或心电α制剂 ELH贝塔和E CG贝塔。其他杂交种由完整的阿尔法- 亚基制剂与截短的DES(121-149)ELH Beta或 DES(121-149)心电β制剂。促黄体生成素和促卵泡刺激素受体检测结果 结合分析表明，α-Asn56寡糖和β-Asn56- O-连接的低聚糖亚单位对 这些激素制剂的受体结合能力。在……里面 相比之下，α-Asn82和β-Asn13寡糖起到了矿物质的作用 在确定ELH和ECG之间的功能差异方面。 使用各种现代酶和化学修饰 ELH和心电α、β的寡糖和多肽链 亚基，一组缺乏特异性的杂交荷尔蒙 低聚糖将被创造出来。这些混血儿的活动将是 在大鼠睾丸黄体生成素放射配基试验中，大鼠睾丸间质细胞 体外和体内类固醇激素生成的心电生物测定。这个 获得的信息将证实Alpha Asn56和Beta O连接 低聚糖对受体结合的影响最大 并将确定最重要的碳水化合物结构 调节类固醇激素的体外和体内生物学活性 这些荷尔蒙。结构研究将确定阿尔法Asn56的特征 和β-O连接的寡糖，它们负责 ELH和ECG的生物活性差异。结果将有助于 了解蛋白质差异糖基化的特性 脑下垂体和胎盘。因为自然环境的独特之处 糖基化这些研究不能用重组DNA进行 技术

The equine gonadotropins, eLH and eCG, bind the same receptors, display both LH and FSH activities, possess identical amino acid sequences, yet differ significantly in their glycosylation patterns. Therefore, all functional differences between them observed in vivo and in vitro are due only to glycosylation. The affinity of eCG for the equine LH receptor is 57- to 75-fold less than that of eLH. The half-life of eCG in circulation is greater than that of eLH. There is widespread use of eCG in biology for promoting follicular development and superovulation either as an end in themselves or as a means to produce large numbers of animals for other studies. Hybrid hormones were prepared from different combinations of intact of ASN56 deglycosylated eLH alpha or eCG alpha preparations with intact eLH beta and e CG beta. Other hybrids consisted of intact alpha- subunit preparations combined with truncated des(121-149)eLH beta or des(121-149)eCG beta preparations. The results of LH and FSH receptor binding assays revealed that alpha Asn56 oligosaccharides and beta- subunit O-linked oligosaccharides exerted a strong negative influence on the receptor binding potency of these hormone preparations. In contrast, alpha Asn82 and beta Asn13 oligosaccharides played a mine role in determining the functional differences between eLH and eCG. Using a variety of modern enzymatic and chemical modifications of oligosaccharides and polypeptide chains of eLH and eCG alpha and beta subunits, a panel of hybrid hormones deficient in specific oligosaccharides will be created. The activities of these hybrids will be tested in a rat testis LH radioligand assay, rat testis Leydig cell steroidogenesis assay in vitro and in an in vivo eCG bioassay. The information obtained will confirm that alpha Asn56 and beta O-linked oligosaccharides have the most significant effect on receptor binding activity and will identify the carbohydrate structures most important for modulating the in vitro steroidogenic and in vivo biological activities of these hormones. Structural studies will identify features of alpha Asn56 and beta O-linked oligosaccharides that are responsible for the differences in bioactivity between eLH and eCG. The results will help to understand the peculiarities of differential glycosylation of proteins in the pituitary and placenta. Because of the unique features of natural glycosylation these studies can not be performed with recombinant DNA technology.