STRUCTURE-FUNCTION RELATIONSHIPS OF THE IGE RECEPTOR

IGE 受体的结构与功能关系

• 批准号: 3127827
• 负责人: Barbara A Baird
• 金额: $ 14.94万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1981
• 资助国家: 美国
• 起止时间: 1981-08-01 至 1992-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3127827
• 关键词: affinity chromatography; antibody receptor; cell fusion; cell membrane; chemical structure function; cytoskeleton; fluorescent dye /probe; genetic mapping; immunochemistry; immunogenetics; immunoglobulin E; laboratory rat; mast cell; membrane activity; monoclonal antibody; protein engineering; protein structure; protein structure function; receptor; tissue /cell culture

The work proposed continues the systematic analysis of the three- dimensional structure of the immunoglobulin E (IgE) -receptor complex, its interactions with other cellular components, and the mechanism by which it transmits a signal across the plasma membrane of mast cells and basophils to trigger degranulation in allergic responses. The structural map will be extended by measurements of resonance energy transfer between well defined sites on receptor-bound IgE and cytoplasmically exposed portions of the receptor that are labeled by monoclonal antibodies. Regions of IgE that are critical for its interaction with receptor will be examined by genetic manipulation of the polypeptide chains. Genetic methods will also be used to introduce specific cysteine residues for fluorescent labeling such that energy transfer measurements may be carried out to test the model that IgE undergoes a conformation change upon binding. In addition to providing basic information knowledge of the IgE-receptor interaction may be valuable in clinical treatments of allergies. The interactions between receptors and other cellular components that occur after lgE-receptor complexes have clustered in a triggering configuration will be investigated by fluorescence photobleaching recovery and electrodiffusion measurements of the lateral mobility of fluorescently labeled monoclonal antibodies that dimerize the receptors or are specific for a partially characterized component that appears to associate with receptors. A procedure for measuring rotational mobility by steady-state phosphorescence anisotropy will be developed such that time-dependent changes in the receptor interactions may be monitored under conditions where cell triggering occurs. The particular components that interact with the clustered receptors will be characterized with the use of differential chemical crosslinking, radioactive labeling and purification schemes. The participation of the cytoplasmically exposed parts of the receptor in interactions with other cellular components during signal transduction will be investigated by testing the competence of lgE-receptor complexes with proteolyzed cytoplasmic portions after reconstitution into intact cells and also by microinjection into cells of the monoclonal antibodies specific for cytoplasmic portions. These studies should contribute new insights to understanding the chain-of-events between antigen bridging of lgE-receptor complexes on the cell surface and the degranulation signal.

提出的工作继续对三个的系统分析 免疫球蛋白E（IgE） - 受体的尺寸结构 复合物，其与其他细胞成分的相互作用，以及 它在等离子体上传输信号的机制 肥大细胞和嗜碱性的膜以触发脱粒 过敏反应。 结构图将扩展 定义良好的共振能量转移的测量 受体结合的IgE和细胞质暴露部分的位置 由单克隆抗体标记的受体的。 IgE的区域对于与受体相互作用至关重要 将通过多肽的遗传操作来检查 链。 遗传方法也将用于引入特定 荧光标记的半胱氨酸残基，使能量 可以进行转移测量，以测试模型 IgE在结合时会发生构象变化。 此外 提供IGE受体的基本信息知识 相互作用可能在过敏的临床治疗中很有价值。 受体与其他细胞成分之间的相互作用 在LGE受体复合物聚集在A中之后发生的 触发配置将通过荧光研究 光漂白的恢复和电泄漏测量 荧光标记的单克隆的横向迁移率 二聚体或特定于A的抗体 部分表征的组件似乎与 受体。 测量旋转迁移率的程序 稳态磷光各向异性将开发 受体相互作用的时间依赖性变化可能是 在发生细胞触发的条件下监测。 这 与聚类受体相互作用的特定成分 使用差分化学的特征 交联，放射性标记和纯化方案。 这 受体的细胞质暴露部分的参与 在信号期间与其他细胞成分的相互作用中 通过测试的能力来调查转导 LGE受体复合物与蛋白水解细胞质部分 重组成完整的细胞后，也通过显微注射 进入对细胞质特异的单克隆抗体的细胞 部分。 这些研究应该为 了解抗原桥接之间的事件链 细胞表面上的LGE受体复合物和脱粒 信号。