Determining the mechanism of mitochondrial outer membrane fusion

确定线粒体外膜融合的机制

基本信息

批准号：
10441835
负责人：
Suzanne C Hoppins
金额：
$ 33.53万
依托单位：
UNIVERSITY OF WASHINGTON
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-02-01 至 2026-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10441835
关键词：
Address Aging Allosteric Regulation Apoptotic Ataxia Automobile Driving Behavior Binding Binding Proteins Biochemical Biochemistry Biological Assay Biology Blood Coagulation Factor VII Cell physiology Cells Cellular biology Collection Complement Complex Cytoplasmic Protein Cytosol Data Defect Development Disease Dynamin Event Family Fluorescence Resonance Energy Transfer Foundations GTP Binding Genes Goals Guanosine Triphosphate Guanosine Triphosphate Phosphohydrolases Health Homology Modeling Hydrolysis Impairment Knowledge Link Maps Mediating Membrane Membrane Fusion Metabolic Microtubules Mitochondria Modeling Molecular Molecular Conformation Movement Muscle Mutation Myopathy Nerve Degeneration Neurodegenerative Disorders Neurons Optic Atrophy Organelles Outer Mitochondrial Membrane Pathway interactions Patients Peripheral Nervous System Diseases Polymers Positioning Attribute Production Property Protein Dynamics Proteins Publishing Regulation Research Shapes Stimulus Stress Structure Techniques Testing Transmembrane Domain Tubulin Variant Work age related base experimental study flexibility insight mitochondrial dysfunction novel novel strategies paralogous gene pro-apoptotic protein programs reconstitution self assembly therapeutic development tool

项目摘要

Project Summary This proposal examines the mitofusin proteins, which catalyze both mitochondrial tethering and outer membrane fusion. Mitochondrial shape is central to mitochondrial function and is closely linked to changes in cellular physiology during development, stress, and aging. Mitochondrial fusion increases metabolic production, protects against excessive degradation of mitochondria, reduces sensitivity of the cell to apoptotic stimuli and allows functional complementation of damaged organelles. Compromised mitochondrial function and decreased organelle connectivity are associated with neurodegeneration and other age-related diseases. Furthermore, mutations in the genes encoding components of the mitochondrial fusion machine cause peripheral neuropathy, optic atrophy, myopathy and ataxia. Both mitochondrial division and mitochondrial fusion are mediated by conserved dynamin superfamily proteins. This diverse family of mechanochemical GTPases couple self-assembly and conformational changes to membrane remodeling events throughout the cell. Mitofusin is the mitochondrial outer membrane fusion machine and must assemble both in cis within a single membrane, and in trans across two mitochondria. The molecular details, including of the composition of these assemblies, the regulation of their formation and how they contribute to membrane tethering and fusion are not known. We address these gaps in knowledge utilizing biochemical analyses of mitofusin function. In Aim 1, we will elucidate mechanisms of allosteric regulation that control assembly of mitofusin into fusion- competent complexes. Our collection of functional variants and novel approaches will provide a powerful tool in dissecting the contribution of each mitofusin functional domain to cis oligomerization and trans complex formation. Our work characterizing CMT2A-associated variants of mitofusin revealed that molecular defects of mitofusin can be compensated for by cytosolic factors in cells. In Aim 2, we use a reductionist approach that combines cell biology, biochemistry, and reconstituted assays developed in my lab to determine how the cytosolic mitofusin effectors Bax and MSTO1 alter mitofusin assembly to regulate mitochondrial fusion. This research program draws on our strengths in cellular and biochemical analysis of mitochondrial biology and will yield fundamental insights not only for mitochondrial dynamics but for the mechanisms through which dynamin superfamily proteins in general operate.

项目摘要该提案检查了线粒体蛋白，该蛋白质催化线粒体束缚和外部膜融合。线粒体形状是线粒体功能的核心，与变化紧密相关发育，压力和衰老期间的细胞生理。线粒体融合增加了代谢产生，防止线粒体过度降解，可降低细胞对凋亡刺激的敏感性允许受损细胞器的功能互补。线粒体功能和细胞器连通性降低与神经变性和其他与年龄有关的疾病有关。此外，在编码线粒体融合机的基因中的突变原因周围神经病，视神经萎缩，肌病和共济失调。线粒体分裂和线粒体都融合是由保守的动力蛋白超家族蛋白介导的。这个多元化的机械化学家族 GTPASE夫妇在整个过程中对膜重塑事件的自组装和构象变化细胞。线粒体是线粒体外膜融合机，必须在顺式中组装单个膜，在两个线粒体跨越跨膜中。分子细节，包括这些组件，其形成的调节以及它们如何贡献膜的束缚和融合不知道。我们利用有丝属素功能的生化分析来解决知识中的这些差距。在 AIM 1，我们将阐明将丝线组装到融合中的变构调节机制合格的复合体。我们的功能变体和新颖方法的集合将提供强大的工具在解剖每个丝线素功能结构域对顺式寡聚和反式复合物的贡献时形成。我们表征了丝线曲霉蛋白的CMT2A相关变体的工作表明，分子缺陷丝属素可以通过细胞中的胞质因子补偿。在AIM 2中，我们使用一种还原主义的方法结合细胞生物学，生物化学和在我的实验室中开发的重构测定法胞质丝线素效应BAX和MSTO1改变丝线素组件以调节线粒体融合。这研究计划借鉴了我们在线粒体生物学的细胞和生化分析方面的优势，并将产生基本见解，不仅是线粒体动力学的基本见解一般操作中的超家族蛋白。