STRUCTURE-FUNCTION RELATIONSHIPS OF THE IGE RECEPTOR

建议的工作继续对三个方面进行系统分析-- 免疫球蛋白E(IgE)受体的空间结构 复合体，它与其他细胞组件的相互作用，以及 它通过等离子体传输信号的机制 肥大细胞膜和嗜碱性粒细胞触发脱颗粒 过敏反应。结构图将扩展为 明确定义之间的共振能量传递的测量 受体结合的IgE和细胞质暴露部分上的位点 由单抗标记的受体。 免疫球蛋白E与受体相互作用的关键区域 将通过对多肽的遗传操作进行检查 锁链。遗传方法也将被用来引入特定的 半胱氨酸残基用于荧光标记，使能量 可以执行传输测量以测试该模型 免疫球蛋白在结合后发生构象变化。除了……之外 提供有关IgE受体的基本信息知识 相互作用在过敏的临床治疗中可能是有价值的。 受体与其他细胞成分之间的相互作用 在LGE-受体复合体聚集在一个 触发配置将通过荧光法进行研究 光漂白回收率和电扩散测量 荧光标记单抗的侧向迁移率 使受体二聚化或特异性的抗体 部分特征化的组件，看起来与 感受器。通过以下方法测量旋转迁移率的程序 稳态磷光各向异性将发展为 受体相互作用的时间依赖性变化可能是 在发生小区触发的条件下进行监控。这个 与簇状受体相互作用的特定成分 将通过使用不同的化学物质来表征 交联剂、放射性标记和纯化方案。这个 受体胞质暴露部分的参与 在信号过程中与其他细胞组件的相互作用 转导的调查将通过测试的能力 含蛋白降解胞浆部分的IgE受体复合体 在重建成完整的细胞之后，也可以通过显微注射 进入细胞内的胞浆特异性单抗 一份。这些研究应该会为以下方面提供新的见解 了解抗原桥接之间的事件链 细胞表面IgE受体复合体与脱颗粒 信号。

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.