DESIGN OF MULTIMERIC INTERLEUKIN-2 RECEPTOR ECTODOMAINS

白细胞介素-2：白细胞介素-2受体的相互作用一直是研究白细胞介素-2相互作用的热点之一。 最深入研究的配体受体系统 造血/淋巴因子家族。 最近的研究结果表明， 这一制度在许多方面仍然是个谜。 不仅是生物化学 信号转导机制未知，但在过去的一年里， IL-2的长期三维结构已被证明是 不正确的和第三个细胞表面受体亚基已被确定。 三种细胞表面亚基（p55、p64和p75）的存在使得 受体系统在造血干细胞的不断扩大的家族中是独一无二的， 受体。 了解每个亚单位如何与 配体捕获、信号传递和内在化是必不可少的 用于开发基于配体的IL-2激动剂和拮抗剂。 我们 和其他人已经证明，这些亚单位必须发挥作用， 异二聚体在细胞表面。 只有一个亚基（p55）是 能够与溶液中的配体以类似于 细胞表面结合 该项目的长期目标是设计 可溶性IL-2受体胞外域以定向多聚体形式缔合 时尚的解决方案，利用丰富的知识， 卷曲螺旋（Leu Zipper）分子特异性和稳定性 识别. 该项目的具体目标是： A.设计并表达融合蛋白，使之联合收割机 具有卷曲螺旋识别序列的胞外域， 在溶液中特异性指导亚基相互作用。 B。 使用生物物理学方法表征受体亚基复合 方法. C. 为了定量可溶性受体的配体结合特性， 复合物，并将它们与等效的细胞表面结构进行比较。 D.为了优化可溶性复合物的设计， 将极大地促进这种配体受体的表征 系统 此外，这些结果将证明 这种方法用于研究造血系统的其他成员， 受体家族

The interleukin-2: Interleukin-2 receptor interaction has been one of the most intensely investigated ligand receptor system of the hematopoietic/lymphokine family. Recent findings demonstrate that is system remains an enigma in many respects. Not only is the biochemical mechanism of signal transduction unknown, but within the last year the longstanding 3 dimensional structure for IL-2 has been shown to be incorrect and a third cell surface receptor subunit has been identified. The presence of three cell surface subunits (p55, p64 and p75) makes this receptor system unique among the expanding family of hematopoietic receptors. The knowledge of how each subunit functions with respect to ligand capture, signal transmission and in internalization is essential for the development of ligand based IL-2 agonists and antagonists. We and others have demonstrated that these subunits must function as heterodimers on the cell surface. Only one of the subunits (p55) is capable of interacting with ligand in solution in a manner that resembles cell surface binding. The long term goal of this project is to engineer soluble IL-2 receptor ectodomains that associate in a directed multimeric fashion in solution by exploiting the wealth of knowledge concerning the specificity and stability of coiled - coil (Leu Zipper) molecular recognition. The Specific Aims of this project are: A. To engineer and express fusion proteins that combine each receptor ectodomain with coiled- coil recognition sequences designed to specifically direct subunit interaction in solution. B. To characterize receptor subunit complexation using biophysical methods. C. To quantitate the ligand binding properties of the soluble receptor complexes and compare them to the equivalent cell surface structures. D. To optimize the designs of the soluble complexes such that bind ligand will greatly facilitate the characterization of this ligand receptor system. In addition, these results will demonstrate the feasibility of this approach for the study of other members of the hematopoietic receptor family.