Structural and functional characterization of ATP synthase c-subunit leak channel and its role in AD pathogenesis

ATP合酶c亚基泄漏通道的结构和功能特征及其在AD发病机制中的作用

• 批准号: 10553483
• 负责人: Nelli Mnatsakanyan
• 金额: $ 183.13万
• 依托单位: PENNSYLVANIA STATE UNIV HERSHEY MED CTR
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-05-15 至 2024-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10553483
• 关键词: Structural; functional; characterization; ATP; synthase

Abstract Mitochondrial and synaptic dysfunction are early pathological features and a driving force of Alzheimer's disease (AD) pathology. Aβ is found to accumulate abnormally in the brains of AD individuals and in an AD mouse models leading to mitochondrial Ca2+ overload and activation of mitochondrial permeability transition pore (mPTP). Prolonged opening of mPTP triggers outer mitochondrial membrane rupture, release of cytochrome c and activation of downstream cell death pathways. The mPTP has been at the center of extensive scientific research for the last several decades but it still remains as one of the most mysterious phenomena in biology today due to its controversial molecular composition and the lack of structural information of its pore. We have recently demonstrated the novel role of ATP synthase c-subunit ring in forming the channel of mPTP. Nevertheless, the gating mechanism of the ATP synthase c-subunit leak channel and conformational changes initiating its opening are yet to be discovered. In this proposal, we will use single-particle cryo-electron microscopy (cryo-EM) to identify the high- resolution structure and the open conformation of ATP synthase leak channel in the presence of channel modulators. We will also perform in situ structural analysis of ATP synthase in its functional environment within the Aβ-exposed primary hippocampal neurons and in mitochondria isolated from the mouse models of AD by using cryo-electron tomography (cryo-ET). In this project we will also investigate the direct role of ATP synthase leak channel as a novel cell death pathway in AD pathogenesis; we will test whether the pharmacological inhibition of this channel will rescue neurons from Aβ-induced cell death. Successful completion of this proposal will reveal the molecular mechanism(s) of mitochondrial permeability transition, the atomic structure of ATP synthase leak channel, and will aid in the development of new treatments for AD, targeting ATP synthase.

抽象的 线粒体和突触功能障碍是早期病理特征，是 阿尔茨海默氏病（AD）病理学。发现Aβ在AD的大脑中异常积累 个体和AD鼠标模型，导致线粒体Ca2+过载和激活 线粒体通透性过渡孔（MPTP）。 MPTP的长时间开放触发了外部 线粒体膜破裂，细胞色素C的释放和下游细胞的激活 死亡道路。 MPTP一直是最后一次科学研究的中心 几十年，但仍然是当今生物学中最神秘的现象之一 由于其有争议的分子组成以及缺乏孔的结构信息。 最近，我们证明了ATP合酶C-亚基环在形成该ATP的新作用 MPTP渠道。然而，ATP合酶C-亚基叶的门控机制 渠道和构象变化启动其开口尚未发现。 在此提案中，我们将使用单粒子冷冻电子显微镜（Cryo-EM）来识别高 - 在存在的情况下，分辨率结构和ATP合酶泄漏通道的开放构象 通道调节器。我们还将在其ATP合酶中进行原位结构分析 暴露于Aβ的原发性海马神经元和线粒体中的功能环境 通过使用冷冻电子断层扫描（Cryo-ET）从AD的小鼠模型中分离出来。在这个项目中 我们还将研究ATP合酶泄漏通道作为新的细胞死亡途径的直接作用 在AD发病机理中；我们将测试该通道的药理学抑制是否会营救 来自Aβ诱导的细胞死亡的神经元。该提案的成功完成将揭示 线粒体通透性跃迁的分子机制，ATP的原子结构 合成酶泄漏通道，并将有助于开发AD的新疗法，以ATP为目标 合酶。