The mechanism of nuclear autophagy

核自噬机制

基本信息

批准号：
10688323
负责人：
Charles Patrick Lusk
金额：
$ 34.32万
依托单位：
YALE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-09-30 至 2024-02-29
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10688323
关键词：
Aging Attention Automobile Driving Autophagocytosis Autophagosome Binding Biochemical Biological Models Cell Aging Cell Nucleus Cells Complement Cytoplasm Cytosol Data Degradation Pathway Disease Dynamin Electron Microscopy Elements Engineering Event Fluorescence Functional disorder Goals Homeostasis Human Impairment In Vitro Individual Intermediate Filaments Kinetics Lamins Light Link Lipids Longevity Lysosomes Mechanics Mediating Membrane Membrane Proteins Microscopy Mitochondria Mitotic Modeling Molecular Mutation Neurodegenerative Disorders Nuclear Nuclear Envelope Nuclear Inner Membrane Nuclear Lamina Nuclear Outer Membrane Nuclear Protein Organelles Pathogenicity Pathway interactions Phenotype Physical condensation Physiological Process Proteins Publishing Quality Control Role Saccharomyces cerevisiae Signal Transduction Site Structural defect System Testing TimeLine Yeasts age related biological adaptation to stress insight light microscopy membrane assembly novel nucleocytoplasmic transport protein aggregation proteostasis receptor reconstitution recruit scaffold

项目摘要

Project Summary Over the last 10 years, the lysosome-mediated degradation pathway macroautophagy has gained prominence in the study of aging-related disorders and extension of lifespan. Macroautophagy is an essential cellular pathway responsible for the elimination of cytosolic proteins, lipids and organelles, and as such, the field has focused upon the role of macroautophagy in clearing protein aggregates or dysfunctional organelles (such as mitochondria) that specifically accumulate in the cytoplasm. Increasingly however, protein accumulation and organelle dysfunction are observed to occur within the nucleus, apparently shielded from cytoplasmic processes by the double-membraned nuclear envelope. Furthermore, links between aging and nuclear envelope structural defects are emerging, including nuclear envelopathies caused by mutations in the envelope scaffolding lamins and associated integral inner nuclear membrane proteins. How the cell responds to these nuclear insults is not well understood, but there is emerging evidence that components of the nuclear envelope and the nucleus are subject to macroautophagy-dependent turnover. Thus, it is clear that we must refocus our attention on how nuclear quality control is executed and specifically on the mechanism(s) that governs nuclear content turnover in cytoplasmic autophagosomes. Thus, in this proposal, we focus on the fundamental question of how cytoplasmic autophagy machinery and nuclear envelope remodeling are coordinated. Using S. cerevisiae, where discovery of the molecular machinery driving nuclear autophagy is the most mature and where we have generated substantial preliminary and recently published data, we will test an exciting “outside-in” model of nucleophagy. This model invokes a novel translumenal bridge that spans the nuclear envelope membranes and connects the cytosol to the nucleus. This proposal will thus fully define the molecular components that make up this nucleophagy pathway and place these factors within an ultrastructural timeline. Elements of this pathway will then be reconstituted using fully engineered in vitro systems in order to collectively provide critical molecular insight into the key membrane remodeling events necessary to remove nuclear contents while maintaining nuclear integrity. With the completion of this project, we will further our mechanistic understanding of a key underappreciated macroautophagic process and open doors to define how nuclear autophagy can impact aging-impaired proteostasis.

项目概要在过去的十年中，溶酶体介导的降解途径巨自噬引起了人们的关注在衰老相关疾病和延长寿命的研究中，巨自噬是一种重要的细胞。负责消除胞浆蛋白、脂质和细胞器的途径，因此，该领域已重点关注巨自噬在清除蛋白质聚集物或功能失调的细胞器（例如然而，蛋白质积累和细胞质中的特异性积累越来越多。观察到细胞器功能障碍发生在细胞核内，显然不受细胞质的影响此外，衰老与核之间的联系。包膜结构缺陷正在出现，包括由基因突变引起的核包膜病。包膜支架核纤层蛋白和相关的完整内核膜蛋白细胞如何反应。人们对这些核侮辱的了解还不是很清楚，但有新的证据表明，核攻击的组成部分包膜和细胞核受到巨自噬依赖性周转的影响，因此，很明显我们必须这样做。我们将注意力重新集中在核质量控制的执行方式上，特别是关注核质量控制的机制。控制细胞质自噬体中的核内容物周转因此，在本提案中，我们重点关注细胞质自噬机制和核膜重塑如何发生的基本问题使用酿酒酵母进行协调，其中驱动核自噬的分子机制的发现是关键。最成熟并且我们已生成大量初步数据和最近发布的数据的地方，我们将测试令人兴奋的“从外到内”的核吞噬模型，该模型调用了一种跨越腔的新型桥。因此，该提案将充分定义核膜和细胞质与细胞核的连接。构成这种核吞噬途径的分子成分并将这些因子置于超微结构中然后将使用完全工程化的体外系统重建该途径的元素，以便共同提供对去除所需的关键膜重塑事件的关键分子洞察随着该项目的完成，我们将进一步推进我们的核内容维护核完整性。对一个被低估的关键巨自噬过程的机制理解，并为定义如何进行打开大门核自噬可以影响衰老受损的蛋白质稳态。