Biogenesis of alpha-helical mitochondrial outer membrane proteins in higher eukaryotes

高等真核生物中α螺旋线粒体外膜蛋白的生物发生

基本信息

批准号：
10723598
负责人：
ALINA-IOANA GUNA
金额：
$ 12.5万
依托单位：
CALIFORNIA INSTITUTE OF TECHNOLOGY
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-08-01 至 2025-07-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10723598
关键词：
Alzheimer&apos s Disease Apoptosis Award Binding Biochemical Biochemistry Biogenesis Bioinformatics Biological Assay CCL21 gene Cell physiology Cells Cellular Stress Cellular biology Collaborations Communication Complex Cytoplasm Data Development Disease Eukaryota Evolution Family Foundations Future Genetic Genome Goals Homeostasis Homologous Gene Human Hydrophobicity In Vitro Innate Immune Response Knowledge Knowledge acquisition Learning Life Lipid Bilayers Lipids Malignant Neoplasms Mammalian Cell Mammals Maps Mediating Membrane Membrane Proteins Mentors Metabolism Mitochondria Mitochondrial Membrane Protein Mitochondrial Proteins Molecular Mutagenesis Neurodegenerative Disorders Nuclear Organelles Organism Orthologous Gene Outcome Outer Mitochondrial Membrane Parkinson Disease Pathway interactions Pharmacologic Substance Phase Physiological Physiology Play Positioning Attribute Postdoctoral Fellow Process Production Proteins Proteome Research Role Route Signal Transduction Site Techniques Testing Time Transmembrane Domain Work alpha helix biochemical tools biophysical properties career crosslink functional genomics genome wide screen genomic tools human disease hydrophilicity in vitro Assay in vivo insight member membrane biogenesis mitochondrial membrane novel peroxisome programs skill acquisition skills solute therapy development

项目摘要

Project Summary/Abstract Mitochondria are essential organelles of endosymbiotic origin which have evolved to play critical roles in eukaryotic physiology. Mitochondrial activity is dependent on proteins embedded in the outer mitochondrial membrane (OMM), which mediate mitochondrial-cytoplasmic communication, and critical aspects of cellular function such as apoptosis and the innate immune response. a-helical proteins are an important subset of OMM proteins. However, how they get inserted into the lipid bilayer of the OMM in mammalian cells has until recently been unclear. Work by myself, in collaboration with Rebecca Voorhees and Jonathan Weissman’s labs, has identified the OMM resident protein MTCH2, a defining member of a novel family of insertases, as both necessary and sufficient for the insertion of a-helical proteins into the OMM. MTCH2 is a diverged member of the solute carrier family 25 (SLC25), and has evolved to exploit the canonical transporter fold for insertion. Bioinformatic analysis reveals that MTCH2 has a homolog in peroxisomes, and orthologs across holozoa, suggesting a common mechanism for a-helical protein insertion across membranes and eukaryotes. Building on this finding, this proposal aims to develop a comprehensive understanding of how a-helical proteins are correctly targeted to the OMM and inserted into the lipid bilayer across eukaryotes. This work will address a fundamental question in cell biology, as the OMM proteome has evolved to support increasingly more complex functions in higher eukaryotes. a-helical proteins are defined by the presence of one or more transmembrane domains (TAs), though their TMs can vary significantly in number and a range of biophysical characteristics such as hydrophobicity. This proposal aims to first develop a deeper understanding of MTCH2 function. First, in vivo and biochemical techniques will be combined to map the route a substrate TM takes through MTCH2 into the lipid bilayer, directly testing whether MTCH2’s conserved hydrophilic groove has a direct role in this process. Second, this work will establish whether structural homologs of MTCH2 have retained their insertase ability across eukaryotes. The biochemical skills and knowledge acquired by defining the molecular basis for MTCH2 will be combined with systematic functional genomics to establish how a-helical proteins get targeted to the OMM, and whether other factors besides MTCH2 are required to support the biogenesis of this diverse class. Cumulatively, this proposal will provide important insights into the mechanisms that have evolved to support eukaryotic life. Further, intimate knowledge of the machinery that governs a-helical OMM protein insertion will be critical for developing new treatments associated with outer mitochondrial membrane protein dysregulation, including neurodegenerative diseases such as Parkinson’s and Alzheimer’s.

项目概要/摘要线粒体是内共生起源的重要细胞器，它已进化到在真核生理学依赖于嵌入线粒体外层的蛋白质。膜（OMM），介导线粒体-细胞质通讯以及细胞的关键方面细胞凋亡和先天免疫反应等功能是重要的子集。然而，OMM 蛋白如何插入哺乳动物细胞中的 OMM 脂质双层中仍然未知。最近不太清楚。我与丽贝卡·沃里斯 (Rebecca Voorhees) 和乔纳森·韦斯曼 (Jonathan Weissman) 的实验室合作，确定了 OMM 驻留蛋白 MTCH2 是新型插入酶家族的定义成员，既是必需的又是足以将α-螺旋蛋白插入OMM中，MTCH2是溶质的分歧成员。载体家族 25 (SLC25)，并已进化为利用经典转运蛋白折叠进行插入。分析表明，MTCH2 在过氧化物酶体中具有同源物，并且在 holozoa 中具有直系同源物，这表明 α-螺旋蛋白跨膜和真核生物插入的常见机制。基于这一发现，该提案旨在全面了解α-螺旋如何这项工作将正确地将蛋白质靶向 OMM 并插入真核生物的脂质双层中。解决细胞生物学中的一个基本问题，因为 OMM 蛋白质组已经发展到支持越来越多的高等真核生物中更复杂的功能是由一个或多个α螺旋蛋白的存在来定义的。跨膜结构域 (TA)，尽管它们的 TM 在数量和生物物理范围上可能存在显着差异该提案旨在首先加深对 MTCH2 的了解。首先，将结合体内和生化技术来绘制底物TM的路径。通过MTCH2进入脂双层，直接测试MTCH2的保守亲水沟是否具有其次，这项工作将确定 MTCH2 的结构同源物是否具有直接作用。它们在真核生物中保留了插入酶能力。通过定义 MTCH2 的分子基础获得的生化技能和知识将是与系统功能基因组学相结合，确定α-螺旋蛋白如何靶向 OMM，以及除了 MTCH2 之外是否还需要其他因素来支持这一多样化类别的生物发生。总的来说，该提案将为支持机制的发展提供重要的见解。此外，对控制α-螺旋 OMM 蛋白插入的机制的深入了解将有助于了解真核生命。开发与线粒体外膜蛋白失调相关的新疗法至关重要，包括帕金森氏症和阿尔茨海默氏症等神经退行性疾病。