PATHOLOG-OMICS - ESSENTIAL TREMOR IN THE BROADER CONTEXT OF NEURODEGENERATION

 描述（由申请人提供）：在过去的5 - 8年中，我们已经确定了特发性震颤（ET）小脑的一组形态学变化，主要集中在浦肯野细胞（PC）内/周围。ET相关病理学的发现引起了极大的兴趣，但也提出了一些难题。在原发性小脑神经退行性疾病如脊髓小脑共济失调（SCA）和多系统萎缩（MSA）中也观察到了其中的几种病理，但这些变化发生的程度尚未正式研究或与ET进行比较。有趣的是，小脑现在越来越多地涉及其他疾病如帕金森病（PD）和肌张力障碍的震颤产生，但他们的小脑病理目前尚未探索。因此，存在很大的形态学数据缺口。在更初级的水平上，我们最近进行了激光捕获显微切割（LCM），以特异性靶向PC，从而促进了细胞的精确评估。 ET的特定分子变化。我们通过直接测序从ET与对照脑的PC分离的RNA（RNA-seq）获得了高度新颖的差异基因表达谱。我们确定了47个差异表达的转录本，它们编码调节神经元功能的蛋白质。然而，尚未进行一组平行的LCM-RNA-seq研究，探索PD、肌张力障碍、MSA和SCA中PC的分子生物学。这代表了第二个大的分子数据缺口。这项为期五年的提案，使用了来自ET患者以及其他一系列小脑疾病患者的死后组织，有两个目的。具体目标1：对小脑进行详细的尸检研究，比较ET患者小脑的形态学变化与原发性小脑退行性疾病（SCA和MSA）患者以及伴有震颤和小脑受累（PD和肌张力障碍）的神经系统疾病患者的形态学变化。我们将收集160个大脑的初始发现样本（50个ET，25个SCA，15个MSA，30个PD，15个肌张力障碍，25个对照）以及160个大脑的重复样本，评估几个小脑隔室的病理变化。将使用量化变量的分层聚类分析来确定是否存在可定义的“ET聚类”以及其他四种疾病中的每一种的可定义聚类。具体目标2：探索以小脑受累和/或震颤为特征的神经退行性疾病中PC的分子生物学。使用一种新的LCM-RNA-seq方法，我们将确定PC中的分子表达变化在这些疾病中是否相同或不同。对于这些新的分子研究，我们建议使用60个大脑（ET、SCA、MSA、PD、肌张力障碍、对照各10个）。

 DESCRIPTION (provided by applicant): Over the past 5 - 8 years, we have identified a cluster of morphological changes in the essential tremor (ET) cerebellum, predominantly centered in/around the Purkinje cell (PC). The discovery of ET-related pathology has generated great interest but it has also raised difficult questions. Several of these pathologies have also been observed in primary cerebellar neurodegenerative diseases such as spinocerebellar ataxias (SCAs) and multiple system atrophy (MSA), but the degree to which these changes occur has not been formally studied or compared with that in ET. Interestingly, the cerebellum is now increasingly being implicated in tremor generation in other diseases such as Parkinson's disease (PD) and dystonia, yet their cerebellar pathology is presently unexplored. Hence, there is a large morphologic data gap. On a more primary level, we recently performed laser-capture microdissection (LCM) to specifically target PCs, thereby facilitating a precise evaluation of cell specific molecular changes in ET. We obtained a highly novel differential gene expression profile by direct sequencing of RNA (RNA-seq) isolated from PCs of ET vs. control brains. We identified 47 differentially expressed transcripts, which code for proteins that regulate neuronal function. However, a parallel set of LCM-RNA-seq studies, exploring the molecular biology of PCs in PD, dystonia, MSA and SCA, have yet to be performed. This represents a second, large molecular, data gap. This five-year proposal, which uses postmortem tissue from patients with ET well as from patients with a range of other cerebellar disorders, has two aims. Specific Aim 1: To undertake detailed postmortem studies of the cerebellum, comparing morphological changes in the cerebellum of ET patients to those of patients with primary cerebellar degenerative diseases (SCA and MSA) as well as those of patients with neurological diseases with tremor and cerebellar involvement (PD and dystonia). We will assemble an initial discovery sample of 160 brains (50 ET, 25 SCA, 15 MSA, 30 PD, 15 dystonia, 25 controls) as well as a replicate sample of 160 brains, assessing pathological changes across several cerebellar compartments. Hierarchical cluster analysis of quantified variables will be used to determine whether there is a definable "ET cluster" as well as definable clusters for each of these other four diseases. Specific Aim 2: To explore the molecular biology of PCs across neurodegenerative diseases characterized by cerebellar involvement and/or tremor. Using a novel LCM-RNA-seq approach, we will determine whether molecular expression changes in PCs are the same or differ across these diseases. For these novel molecular studies, we propose to use 60 brains (10 each of ET, SCA, MSA, PD, dystonia, controls).