COPPER BINDING TO ALPHA-SYNUCLEIN, THE PARKINSON'S PROTEIN

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 α-突触核蛋白(α-syn)与许多神经退行性疾病的发病机制有关，其中最著名的是帕金森-S病(PD)。散发性帕金森病与促进氧化应激和异常氧化还原活性金属代谢的环境因素有关，在体外观察到了金属增强的α-SYN寡聚作用。我们实验室最近的工作集中在了解铜离子在α-SYN聚集中的作用。我们的初步研究表明，铜(II)离子加速了聚集，并且铜离子被结合到α-SYN中，在N-末端附近亲和力最强(基于电感耦合等离子体质谱和荧光猝灭)。我们建议用CuK-EDGE和EXAFS研究WT蛋白和相关突变体中铜结合部位的局部结构。我们将利用XAS对合成的N-末端片段进行补充研究，以确定铜结合位点的配体。我们的研究将检查铜(II)和铜(I)与蛋白质的结合，因为这些结果可能为氧化还原化学在α-SYN病理中的作用提供见解。一旦可溶的铜-蛋白质复合体被表征，我们就可以检测在铜离子存在下产生的α-突触原纤维。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. alpha-Synuclein (alpha-syn) has been implicated in the pathogenesis of a number of neurodegenerative diseases, the best known of which is Parkinson?s disease (PD). The sporadic form of PD has been linked to environmental factors that promote oxidative stress and aberrant redox-active metal metabolism, and metal-enhanced oligomerization of alpha-syn has been observed in vitro. Recent work in our laboratory has focused on the understanding the role of copper ions in the aggregation of alpha-syn. Our initial studies have shown that Cu(II) ions accelerate aggregation and that the copper ions are incorporated into alpha-syn, with the tightest affinity binding near the N-terminus (based on ICP-MS and fluorescence quenching). We propose Cu K-edge and EXAFS studies to examine the local structure of the Cu binding site in the WT protein and in related mutants. We will compliment these studies with XAS on synthetic N-terminal fragments in order to identify the Cu binding site ligands. Our studies will examine both Cu(II) and Cu(I) binding to the protein, as these results could potentially provide insights into the role of redox chemistry in alpha-syn pathology. Once the soluble Cu-protein complexes have been characterized, we are poised to examine alpha-syn fibrils generated in the presence of copper ions.