INTERACTIONS OF ANDROGEN RECEPTOR POLYGLUTAMINE TRACT

描述：（申请人摘要）脊髓和延髓肌萎缩症是 一种以肌肉无力为特征的成人发病的神经变性疾病， 萎缩和肌束震颤 它是一个不断壮大的家庭的一员， 由CAG重复扩增引起的神经退行性疾病， 在相关的蛋白质编码内编码多聚谷氨酰胺区 顺序 我们的假设是，在这些细胞中观察到的神经变性 疾病是由编码蛋白质中毒性功能的获得引起的 由于多聚谷氨酰胺束的存在， 是由特定的蛋白质间相互作用介导的。 该项目提出识别和分离蛋白质（及其相关的 与雄激素受体相互作用的不同长度的 多聚谷氨酰胺束。 这将通过两种方式实现。 首先，我们将使用 酵母双杂交系统来鉴定与氨基酸相互作用的蛋白质 雄激素受体的末端区域，含有24、45或66个谷氨酰胺 重复。 我们还将使用该系统来表征 相互作用的长度上的聚谷氨酰胺道。 我们预计， 在致病过程中发挥作用的相互作用，它应该是 受到谷氨酰胺重复序列长度的影响。 二是 使用放射性标记的噬菌体筛选λ噬菌体表达文库 从纯化的不同重复长度的雄激素受体蛋白， 细菌 这种方法将允许我们差异筛选文库 使用含有不同长度的全长雄激素受体 多聚谷氨酰胺束。 该系统还将被用于 通过以下方法鉴定蛋白质的结合特性： approach. 最后，我们将描述蛋白质的生理相关性， 通过使用细胞培养的这些筛选鉴定的相互作用， 我们开发的转基因模型系统 这些实验的结果应该提供对分子生物学的深入了解。 扩大的多聚谷氨酰胺束对神经元有毒的机制， 因此可以提供治疗干预的靶点。 在 此外，了解神经元中雄激素受体蛋白的相互作用 将增加我们对类固醇激素受体在 这些细胞。

DESCRIPTION: (Applicant's abstract) Spinal and bulbar muscular atrophy is an adult-onset neurodegenerative disease characterized by muscle weakness, atrophy, and fasciculations. It is a member of a growing family of neurodegenerative diseases caused by the expansion of a CAG repeat that encodes a poly-glutamine tract within the associated protein coding sequence. Our hypothesis is that the neurodegeneration seen in these diseases results from the gain of a toxic function in the encoded protein due to the presence of the poly-glutamine tract, and that this toxic effect is mediated by specific protein-protein interactions. This project proposes to identify and isolate proteins (and their associated cDNAs) that interact with androgen receptor containing different length poly-glutamine tracts. This will be done in two ways. First, we will use a yeast two-hybrid system to identify proteins that interact with the amino terminal region of the androgen receptor containing 24, 45, or 66 glutamine repeats. We will also use this system to characterize the dependence of interactions on the length of the poly-glutamine tract. We expect that for an interaction to play a role in the pathogenic process, it should be affected in some way by the length of the glutamine repeat. Second, we will screen a lambda phage expression library using radioactively-labeled androgen receptor proteins of different repeat lengths purified from bacteria. This method will allow us to differentially screen libraries using full-length androgen receptor containing different length poly-glutamine tracts. This system will also be exploited for characterization of binding properties of proteins identified through either approach. Lastly, we will characterize the physiologic relevance of protein interactions identified through these screens using cell culture and transgenic model systems that we have developed. The results of these experiments should provide insights into the molecular mechanism by which expanded poly-glutamine tracts become toxic to neurons, and may consequently provide targets for therapeutic intervention. In addition, understanding androgen receptor protein interactions in neurons will increase our understanding of the role of steroid hormone receptors in these cells.