Impacting mitochondrial function through altered protease activity

通过改变蛋白酶活性影响线粒体功能

• 批准号: 10741597
• 负责人: Gabriel C Lander
• 金额: $ 3.55万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-04-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10741597
• 关键词: Address; Alzheimer' s Disease; Apoptotic; Award; Binding; Biological; Biological Process; Biology; Catalytic Domain; Cells; Cellular biology; Chronic; Cryoelectron Microscopy; Disease; Endowment; Energy Metabolism; Environmental Risk Factor; Etiology; Genetic Induction; Genomic approach; Genomics; Goals; Guanosine Triphosphate Phosphohydrolases; Hand; Health; Hereditary Spastic Paraplegia; Inner mitochondrial membrane; Membrane; Metalloproteases; Mitochondria; Molecular; Morphology; Mutation; Neurodegenerative Disorders; Nucleotides; OPA1 gene; Parkinson Disease; Pathogenesis; Pathologic; Peptide Hydrolases; Proteolysis; Regulation; Resolution; Signal Transduction; Site; Spinocerebellar Ataxias; Stress; Structure; Structure-Activity Relationship; Therapeutic; Zinc; functional genomics; functional/structural genomics; human disease; insight; mitochondrial dysfunction; mutation screening; pharmacologic; proteostasis; response; therapeutic target

SUMMARY Mitochondrial dysfunction is a pathologic hallmark in the onset and pathogenesis of nearly all neurodegenerative diseases. One of the primary determinants in dictating mitochondrial function is the activity of inner membrane (IM) proteases including the ATP-dependent AAA+ zinc metalloproteases YME1L and AFG3L2 and the ATP- independent zinc metalloprotease OMA1. These proteases regulate many different aspects of mitochondrial biology and function to protect mitochondria from pathologic insults. However, imbalances in the activity of IM proteases induced by genetic or environmental factors are implicated in the pathogenesis of etiologically-diverse diseases including many neurodegenerative disorders. Despite this, the molecular mechanisms by which IM proteases regulate mitochondrial biology remain poorly understood. Here, we are applying a structure-driven approach to determine the molecular mechanisms by which IM proteases regulate mitochondria in the context of health and disease. We previously solved the first high-resolution structures of the IM AAA+ proteases YME1 and AFG3L2. Our structures showed that these two proteases employ a conserved nucleotide-driven, hand- over-hand mechanism to translocate substrates into a privileged proteolytic chamber for proteolysis. Surprisingly, we also identified unique structural features of YME1 and AFG3L2 that integrate into this conserved translocation mechanism to distinctly influence protease activity and stability. Here, we hypothesize that these unique structural differences endow IM proteases with different mechanistic and biologic functions important for their regulation of mitochondria. To address this, we are using a combination of cryo-electron microscopy and cell biology to determine how structural differences in IM AAA+ proteases influence their mechanochemical cycle and enable proteases to perform distinct biological functions. This will reveal new insights into the molecular mechanisms by which IM AAA+ proteases regulate mitochondria in health and disease. Furthermore, we are extending this study utilizing both functional genomic and structural approaches to establish a structure-function relationship that explains the activation and proteolytic activity of the ATP-independent, stress-activated IM protease OMA1 – a protease whose dysregulation is implicated in the pathologic mitochondrial dysfunction associated with many human diseases. Through these efforts, we will define how IM proteases utilize distinct structural features to perform the myriad of biological functions required for the proper regulation of mitochondrial proteostasis and function. Furthermore, we will reveal new insights into the pathologic and potentially therapeutic implications of altered mitochondrial IM protease activity in human disease and identify new opportunities to pharmacologically target IM proteases to mitigate mitochondrial dysfunction associated with many neurodegenerative disorders.

概括 线粒体功能障碍是几乎烯丙基烯丙基苯甲酸的发病机理中的病理标志 疾病。 （IM）包括依赖ATP的AAA+锌金属蛋白酶的蛋白酶YME1L和AFG3L2以及ATP- 独立的金属蛋白酶OMA1。 生物学和功能可保护线粒体免受病理侮辱的影响。 由遗传或环境因素诱导的蛋白酶与病原质多样的发病机理有关 尽管如此 蛋白酶调节线粒体生物学仍然可以理解。 确定IM蛋白酶在上下文中调节线粒体的分子机制的方法 健康和疾病。 和AFG3L2。 过度的机制将基材转移到 我们还确定了YME1和AFG3L2的独特结构特征，这些特征集成到此保守的易位中 分散的机制会影响蛋白酶活性和稳定性。 结构差异赋予具有不同机械和生物学功能的重要性 对于线粒体的调节。 和细胞生物学，以确定IM AAA+蛋白酶中的结构差异如何影响其机械 循环并使蛋白酶执行不同的生物学功能。 IM AAA+蛋白酶在健康和疾病中调节线粒体的机制 扩展这项研究，利用功能性基因组和结构方法来建立结构功能 关系解释了非ATP独立，应力激活的激活和蛋白质活性 蛋白酶OMA1-一种蛋白酶，其失调与病理性线粒体功能障碍有关 与许多人类疾病相关。 结构特征，以执行适当调节米奇氏菌所需的无数生物学功能 蛋白质和功能。 改变了米孔室IM蛋白酶在人类疾病中的影响并确定新机会 药理学靶向IM蛋白酶以减轻许多线粒体功能障碍 神经退行性疾病。