Modifiers of PINK1 function in Parkinson's disease

帕金森病（PD）与多巴胺能细胞的损失相关，并且与在由蛋白质错误折叠和氧化损伤引起的细胞应激的管理中起作用的蛋白质遗传相关。最近发现的PINK1基因突变导致常染色体隐性PD。该提案的主要目的是确定PINK1的分子途径和突变形式的影响。肌张力障碍和PD的明显重叠促使我们研究PINK1和TorsinA的相互作用。人类扭转蛋白A是一种突变，引起另一种称为早发性扭转肌张力障碍的运动障碍，在多巴胺能神经元中高度表达。以前的工作已经建立了具有分子伴侣活性的torsins。我们推测TorsinA的伴侣活性可能对线粒体驻留蛋白如PINK1有影响。这些研究旨在确定PINK1参与的致病途径，方法是：i）对从PINK1突变携带者获得的RNA血液样本进行基因表达研究，以及ii）酵母双杂交筛选。为了检验扭转蛋白A与PD中涉及的其他蛋白质可能相互作用的假设，我们将进行i）筛选来自PD患者的基因组DNA中的扭转蛋白A多态性，我们已经显示该多态性改变扭转蛋白A行为，和ii）测试扭转蛋白A对PINK1突变体和对照成纤维细胞和其他细胞类型中的PINK1表达水平和功能的直接影响。

Parkinson s disease (PD) is associated with loss of dopaminergic cells and genetically linked to proteins that function in the management of cellular stress resulting from protein misfolding and oxidative damage. Mutations in the recently discovered PINK1 gene cause autosomal recessive PD. The main objective of this proposal is to determine the molecular pathway of PINK1 and impact of mutated forms. The marked overlap of dystonia and PD prompted us to study the interplay of PINK1 and TorsinA. Human TorsinA, a mutation in which causes another movement disorder termed early-onset torsion dystonia, is highly expressed in dopaminergic neurons. Previous work has established torsins as having molecular chaperone activity. We hypothesize that chaperone activity of TorsinA may have an impact on mitochondrial resident proteins such as PINK1. These studies are designed to determine the disease-causing pathway in which PINK1 is involved by i) gene expression studies on RNA blood samples obtained from PINK1 mutation carriers, and ii) a yeast two-hybrid screen. To test the hypothesis of a possible interaction of TorsinA with other proteins implicated in PD, we will conduct i) screening of genomic DNA from PD patients for a polymorphism in TorsinA which we have shown to modify TorsinA behavior, and ii) test a direct impact of TorsinA on PINK1 expression levels and function in PINK1 mutant and control fibroblasts and other cell types.