Protein homeostasis in a frontotemporal dementia iPSC model

维持蛋白质稳态对神经元来说是一个特殊的挑战，因为神经元对蛋白质的需求很高， 合成、折叠和运输代表了恒定的应力源。蛋白质处理不当的证据是 在几乎所有神经退行性疾病中观察到，包括AD相关痴呆（ADRD）。AAA- ATP酶Valosin-containing蛋白（VCP）在维持蛋白质的多个方面起着核心作用 体内平衡VCP的突变与几种形式的额颞叶变性有关， 或没有并发的运动功能障碍和肌肉骨骼疾病。然而，人们对 这些突变如何影响神经元中VCP功能的不同方面。VCP-T262 A突变导致 家族性额颞叶痴呆伴失语和帕金森综合征。初级神经元的初步研究 用VCP-T262 A转染显示树突状分支的缺陷，并且携带VCP-T262 A的患者成纤维细胞显示树突状分支的缺陷。 内源性突变表现出分泌功能被破坏。用于产生人类神经元和其他神经元的试剂 携带内源性VCP-T262 A突变的相关细胞类型是迫切需要研究的 疾病的病理生理机制。在这个探索性的项目中，我们将创建iPSC的同基因对， 表达T262 A与野生型VCP的品系。我们将分化为皮层神经元，以研究这一点的影响。 与具有ER应激、自噬和高尔基体标记物突变的iPSC衍生的细胞相比， 不同的VCP功能域。我们的长期目标是了解VCP的改变 有助于突触损失，以便这种机制的理解可以转化为新的治疗方法， 接近。

Maintaining protein homeostasis is a particular challenge for neurons, in which a high demand for protein synthesis, folding and transport represents a constant source of stress. Evidence of protein mishandling is observed in nearly all neurodegenerative diseases including the AD-related dementias (ADRD). The AAA- ATPase valosin-containing protein (VCP) plays a central role in maintaining multiple aspects of protein homeostasis. Mutations in VCP have been linked to several forms of frontotemporal lobar degeneration with or without concurrent motor dysfunction and musculoskeletal disease. Yet there is limited understanding of how these mutations affect different aspects of VCP function in neurons. The VCP-T262A mutation causes familial frontotemporal dementia with aphasia and parkinsonism. Preliminary studies in primary neurons transfected with VCP-T262A reveal deficits in dendritic arborization, and patient fibroblasts bearing the endogenous mutation exhibit disrupted secretory function. Reagents to create human neurons and other relevant cell types bearing the endogenous VCP-T262A mutation are critically needed to study pathophysiological mechanisms of disease. In this exploratory project, we will create isogenic pairs of iPSC lines expressing T262A vs. wild type VCP. We will differentiate to cortical neurons to study the effects of this mutation upon ER stress, autophagy and Golgi markers compared to iPSC-derived cells with a mutation in a different VCP functional domain. Our long-range goals are to understand how alterations in VCP contribute to synaptic loss so that this mechanistic understanding can be translated into new therapeutic approaches.