STRUCTURE-FUNCTION OF PLASMA SEX STEROID-BINDING PROTEIN

血浆性类固醇结合蛋白的结构-功能

• 批准号: 3312397
• 负责人: PHILIP H PETRA
• 金额: $ 10.93万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 1981
• 资助国家: 美国
• 起止时间: 1981-04-01 至 1988-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3312397
• 关键词: X ray crystallography; androgens; autoradiography; chemical structure function; estradiol; hormone regulation /control mechanism; human tissue; membrane permeability; menstrual cycle; pregnancy; radiotracer; scintillation counter; sex hormones; steroid hormone; testosterone; tissue /cell culture

We are proposing to continue our long term studies towards understanding the biochemistry and physiology of the plasma sex steroid-binding protein, SBP. The project is divided into two parts: The first will comprise biochemical studies describing the chemical environment of steroid-binding sites to explain how steroids are bound to protein surfaces. We will attempt to identify amino acid residues in the steroid binding sites of both human and rabbit SBP by affinity labeling, and to determine the adjacent amino acid sequence. Since human SBP binds both E2 and T whereas rabbit SBP only binds T, a comparison should reveal the structural elements responsible for binding specificity. We will also undertake an x-ray diffraction analysis on SBP crystals and elucidate the entire amino acid sequence of SBP in an attempt to describe the three-dimensional structure of a steroid-binding protein. The second objective is to understand the role of SBP in the mechanism of action of steroid hormones in relation to reproductive biology. We will test a new hypothesis implicating SBP as a specific carrier of sex steroids across membranes. To this end, we will attempt to identify a SBP receptor on the plasma membrane by incubating 125I-hSBP with MCF-7 and HEC-50 cells in culture, and by in vivo infusion of 125I-rSBP into rabbits followed by autoradiographic examination of reproductive tissues in the electron microscope. We will also induce a long-term SBP withdrawal in the rhesus monkey by infusing F(ab)2 fragments of SBP antibodies and study the effects on the menstrual cycle and pregnancy (parturition).

我们建议继续进行长期研究以了解 血浆性类固醇结合蛋白的生物化学和生理学， 收缩压。 该项目分为两部分： 第一个将包括描述化学物质的生化研究 类固醇结合位点的环境来解释类固醇如何结合 蛋白质表面。 我们将尝试鉴定氨基酸残基 通过亲和标记确定人和兔 SBP 的类固醇结合位点， 并确定相邻的氨基酸序列。 由于人类 SBP 结合 E2 和 T 都结合，而兔子 SBP 仅结合 T，比较应该显示 负责结合特异性的结构元件。 我们还将 对 SBP 晶体进行 X 射线衍射分析并阐明 SBP 的完整氨基酸序列，试图描述 类固醇结合蛋白的三维结构。 第二个目标是了解 SBP 在机制中的作用 类固醇激素与生殖生物学的作用。 我们将 测试一项新假设，表明 SBP 是性类固醇的特定载体 跨膜。 为此，我们将尝试鉴定SBP受体 通过将 125I-hSBP 与 MCF-7 和 HEC-50 细胞一起孵育在质膜上 培养物中，并通过将 125I-rSBP 体内输注到兔子体内，然后 电子生殖组织放射自显影检查 显微镜。 我们还将诱导恒河猴长期停止 SBP 通过向猴子输注 SBP 抗体的 F(ab)2 片段并研究效果 关于月经周期和怀孕（分娩）。