BIOLOGICAL AND BIOCHEMICAL PROPERTIES OF GLYCOSYLATED HUMAN GROWTH HORMONE

我们的长期目标是阐明结构和了解个人的人生长激素（hGH）变异体在健康和疾病状态下的人体生理调节中的作用。作为我们追求这一目标的下一个目标，我们建议在本申请中研究一种新鉴定的hGH变体：巯基乙醇抗性（MER）45 kDa hGH的结构和生物学作用。由于其新奇，我们对其结构和生物学作用的认识存在空白。本申请的中心假设是，使MER 45 kDa hGH不同于22 kDa hGH的结构组分也使其生物活性不同于22 kDa hGH。拟议研究背后的基本原理是，最近研究的GH和催乳素的结构变体具有与其各自主要亚型不同的生物活性。为了验证这一假设，本研究计划将侧重于确定MER 45 kDa HGH的结构和生物活性。将在一组代表性体外和体内生物测定中评估MER 45 kDa hGH的催乳素样和GH样特性。具体目标是：1）确定MER 45 kDa hGH的结构; 2）确定MER 45 kDa hGH在一系列生物测定中的生物效价，所述生物测定是GH作用的量度; 3）将MER 45 kDa hGH的结构与其生物功能相关联; 4）为了产生抗MER 45 kDa hGH单克隆抗体用于开发同种型-特异性免疫测定将是识别其生理调节的重要工具。本研究的目的是确定MER 45 kDa hGH的结构，阐明其生理意义，确定其构效关系，并建立一种亚型特异性免疫分析方法。本研究所获得的新信息将填补我们目前对MER 45 kDa hGH构效关系认识上的差距。新的治疗策略可能会从这些研究中产生。

Our long range goal is to elucidate the structures and understand the roles of individual human growth hormone (hGH) variant sin the regulation of human physiology in health and disease states. As our next objective in pursuit of this goal, we propose in this application to investigate the structure and biological roles of a newly identified hGH variant: mercaptoethanol-resistant (MER) 45 kDa hGH. Due to its novelty, there exists a gap in our knowledge regarding its structure and biological actions. The central hypothesis of the application is that structural components that make MER 45 kDa hGH different from the 22 kDa hGH also make its biological activities different from that of 22 kDa HGH. The rationale behind the proposed research centers on the fact that structural variants of GH and prolactin that have recently been studied possess biological activities that differ from those of their respective major isoforms. To test the hypothesis, this research plan will focus on ascertaining the structure and biological activities of MER 45 kDa HGH. Both the prolactin-like and GH-like properties of MER 45 kDa hGH will be assessed in a set of representative in vitro and in vivo bioassays. The specific objectives are: 1) To determine the structure of MER 45 kDa hGH; 2) To determine the biological potencies of MER 45 kDa hGH in a range of biological assays that are measures of GH action; 3) To correlate the structure of MER 45 kDa hGH to its biological functions; 4) To generate anti-MER 45 kDa hGH monoclonal antibodies for use in development of an isoform-specific immunoassay that will be an important tool in discerning its physiological regulation. At the conclusion of this research, we expect to have determined the structure of MER 45 kDa hGH, elucidate its physiological significance, ascertained it structure-activity relationships and developed an isoform- specific immunoassay The new information gained from the research of the present proposal will fill the gap in our current understanding of the structure-function relationships of MER 45 kDa hGH. New therapeutic strategies could result from these investigations.