The role of Miro at endoplasmic reticulum-mitochondria contacts in health and disease

Miro 在内质网-线粒体接触中对健康和疾病的作用

• 批准号: 2397875
• 金额: --
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2397875
• 关键词: role; Miro; endoplasmic; reticulum; mitochondria

Endoplasmic reticulum-mitochondria contacts (ERMCs) play a key role in a range of physiological processes including calcium homeostasis, autophagy, apoptosis, and lipid metabolism (Shirokova et al., 2020). The dysregulation of both the function and ultrastructure of these inter-organellar contacts has been observed in diseases such as Amyotrophic lateral sclerosis, Alzheimer's, and Parkinson's disease (PD) (De Mario et al., 2017). Indeed, it is postulated that the malfunction of ERMCs is a major early contributor to the pathogenic end-point in neurodegenerative disease. Despite these observations, our understanding of the mechanisms underpinning the regulation of ERMCs is still limited, particularly in neurons. This knowledge could provide clarity to dysfunction in disease and help identify new targets for therapeutics. The Mitochondrial Rho GTPase (Miro) family are outer mitochondrial membrane proteins that localize at ERMCs. Miro is known to interact with several proteins which accumulate at ERMCs, such as the Mitofusins (Misko et al.,2010), and both the Drosophila and Yeast homologs are associated with regulatory roles at ERMCs (Lee et al., 2016; Kornmann et al., 2011). Moreover, Miro knock-out and PD-related Miro1-mutants altered ERMC ultrastructure whilst simultaneously dysregulating calcium homeostasis in human cell lines (Modi et al., 2019; Berenguer-Escuder et al., 2019). While there is growing evidence of a regulatory mechanism controlling the number of contacts and their components, potentially underpinned by Miro, the types of contacts targeted and the mechanism by which Miro regulates them remains unclear. Thus, we aim to utilise confocal, super resolution, and electron microscopy to explore the role of Miro in ERMC regulation in primary cultured neurons and ex vivo brain tissue. Moreover, we will apply molecular and cell biology techniques to explore the functional and structural implications of Miro dysfunction on specific protein contacts. Our investigation will utilise pre-existing in-lab mouse Miro1/2 knock-out lines (López-Doménech et al., 2018) and Miro1-constructs, including PD-related mutants and signaling mutants. We hope to provide further insight into the regulatory processes at ERMCs and their dysregulation in the neurodegenerative process.

内质网-线粒体接触（ERMC）在一系列生理过程中起关键作用，包括钙稳态、自噬、凋亡和脂质代谢（Shirokova等人，2020年）。已经在诸如肌萎缩侧索硬化症、阿尔茨海默病和帕金森病（PD）的疾病中观察到这些细胞器间接触的功能和超微结构两者的失调（De Mario等人，2017年）。事实上，据推测，ERMC的功能障碍是神经退行性疾病中致病终点的主要早期因素。尽管有这些观察结果，我们对ERMCs调节机制的理解仍然有限，特别是在神经元中。这些知识可以澄清疾病中的功能障碍，并帮助确定新的治疗靶点。线粒体Rho GT3（Miro）家族是定位于ERMC的线粒体外膜蛋白。已知Miro与在ERMC处积累的几种蛋白质相互作用，例如Mitofusins（Misko等人，2010），并且果蝇和酵母同源物都与ERMC的调节作用相关（Lee et al.，2016; Kornmann等人，2011年）。此外，Miro敲除和PD相关的Miro 1突变体改变了ERMC超微结构，同时在人细胞系中失调钙稳态（Modi et al.，2019; Berenguer-Escuder等人，2019年）。虽然越来越多的证据表明，有一种控制联系人数量及其组成部分的监管机制，可能以米罗为基础，但目标联系人的类型以及米罗对其进行监管的机制仍不清楚。因此，我们的目标是利用共聚焦，超分辨率和电子显微镜，探讨米罗在ERMC调节原代培养的神经元和离体脑组织中的作用。此外，我们将应用分子和细胞生物学技术来探索Miro功能障碍对特定蛋白质接触的功能和结构影响。我们的研究将利用预先存在的实验室小鼠Miro 1/2敲除系（López-Doménech et al.，2018）和Miro 1构建体，包括PD相关突变体和信号转导突变体。我们希望提供进一步的洞察ERMCs的调节过程及其在神经退行性过程中的失调。