Global Intracellular Responses to Mitophagy

项目总结 阿尔茨海默病(AD)和帕金森病(PD)是最常见的与年龄相关的神经退行性变 痴呆症患者表现出认知功能丧失的疾病。AD和PD都有 广泛存在于大脑各处的神经病理特征，蛋白聚集体由淀粉样β蛋白组成 (AB)和α-突触核蛋白。虽然AD与抗体和tau沉积有关，但聚集的刘易斯 帕金森病的小体由α-突触核蛋白组成，也在AD的尸检组织中发现。另一个共性 在这些疾病之间，为神经元提供能量的功能障碍的线粒体是其中的一部分 在蛋白质过度聚集和神经变性之前最早可检测到的生化变化。 选择性自噬途径专门针对磨损或损坏的细胞器或蛋白质聚集体 溶酶体的降解。然而，为什么选择性的自噬途径，如有丝分裂吞噬(移除 线粒体受损)和吞噬(去除蛋白质聚集体)能够循环利用或跟上 神经退行性疾病中线粒体受损和错误折叠聚集蛋白的数量？R35 家长奖致力于了解两个生物学过程：有丝分裂和细胞分裂是如何密切相关的 已链接。对细胞器间的连接和协调不同细胞行为的机制的理解是 缺乏。为了更好地了解线粒体在细胞分裂过程中的遗传模式，父母的资助旨在 询问受损线粒体和中心体之间的通讯机制 在有丝分裂期间。在这种情况下，有丝分裂吞噬和聚集吞噬机制不能 保护细胞的关键是它们的调控与这两个过程所需的共同接头蛋白负相关。 此外，尽管已知的神经退行性疾病聚集体，如TDP-43和亨廷顿蛋白 通过吞噬清除，痴呆症相关的吞噬清除机制研究不足。这是一年制 修订申请建议理解吞噬有丝分裂和吞噬集聚是如何联系在一起的，或者是被增强了 或在受到神经变性之前的事件刺激时被抑制。使用暴露于 α-突触核蛋白预成纤维(PFF)，会导致α-突触核蛋白聚集和线粒体功能障碍。这 补充建议：刻画PFF中吞噬有丝分裂和凝集之间的动态通量 暴露的神经元，以确定它们对共享适配器蛋白的依赖。执行定量蛋白质组学以 发现pff在神经元中诱导吞噬的其他关键成分。在整个大脑中使用光学清除， 通过基因操作量化PFF诱导的啮齿动物的聚集物形成和聚集清除 自噬途径。这份为期一年的建议书将为未来的建议书奠定基础，使其易于理解 操纵有丝分裂和吞噬的机制，以确保这两个过程都像 有可能延缓痴呆症相关神经退行性疾病的进展。

PROJECT SUMMARY Alzheimer’s disease (AD) and Parkinson’s disease (PD) are the most common age-related neurodegenerative diseases where patients display a loss of cognitive function with dementia. AD and PD both have neuropathological features widespread throughout the brain with protein aggregates made up of amyloid beta (Ab ) and a-synuclein, respectively. Although AD is associated with Ab and tau deposits, aggregated Lewy bodies in PD are comprised of a-synuclein and are also found in AD post-mortem tissue. Another commonality between these diseases is that dysfunctional mitochondria, which provide energy to neurons, are some of earliest detectable biochemical changes prior to excessive protein aggregation and neurodegeneration. Selective autophagy pathways specifically target worn out or damaged organelles or protein aggregates for degradation at the lysosome. However, why aren’t selective autophagy pathways such as mitophagy (removal of damaged mitochondria) and aggrephagy (removal of protein aggregates) able to recycle or keep up with the number damaged mitochondria and misfolded aggregated proteins in neurodegenerative diseases? The R35 parent award is working to understand how two biological processes: mitophagy and cell division are intimately linked. The understanding of interorganelle connectivity and mechanisms to coordinate diverse cell behaviors is lacking. To better understand the inheritance patterns of mitochondria during cell division, the parent grant aims to interrogate the mechanisms enabling communication between damaged mitochondria and centrosomes during mitosis. In this vein, one possible reason that mitophagy and aggrephagy mechanisms are not able to protect the cell is that their regulation is negatively linked by shared adaptor proteins required for both processes. Also, even though neurodegenerative disease aggregates such as TDP-43 and huntingtin are known to be cleared by aggrephagy, dementia related aggrephagy clearance mechanisms are understudied. This 1-year amendment application proposes to understand how mitophagy and aggrephagy are linked and either enhanced or inhibited when stimulated by the events that precede neurodegeneration. Using primary neurons exposed to a-synuclein preformed fibrils (PFF), we will induce a-synuclein aggregation and mitochondrial dysfunction. This supplement proposes to: Characterize the dynamic flux temporal between mitophagy and aggrephagy in PFF exposed neurons to determine their reliance on shared adaptor proteins. Perform quantitative proteomics to discover other key components to aggrephagy induced by PFFs in neurons. Use optical clearing in whole brains, to quantify aggregate formation and clearance by aggrephagy in PFF induced rodents genetically manipulating autophagy pathways. This 1-year proposal will build the foundational work for future proposals to understand mechanisms to manipulate mitophagy and aggrephagy to ensure both processes are working as efficiently as possible to delay the progression of dementia related neurodegenerative diseases.