Death and Destruction: How the Ubiquitin Proteasome System Executes Linker Cell-type Death

死亡与破坏：泛素蛋白酶体系统如何执行连接细胞型死亡

• 批准号: 10464485
• 负责人: Lauren Bayer Horowitz
• 金额: $ 6.76万
• 依托单位: ROCKEFELLER UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-28 至 2024-09-27
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10464485
• 关键词: Animals; Antibodies; Apoptosis; Apoptotic; Binding; Biological; Caenorhabditis elegans; Caspase; Cell Death; Cell Death Process; Cell Survival; Cells; Cessation of life; Characteristics; Chromatin; Chromatin Structure; Cullin Proteins; Data; Defect; Development; Disease; Electron Microscopy; Embryo Loss; Enzymes; Epithelial Cells; Etiology; Exhibits; Female; Genes; Genetic; Genetic Epistasis; Genetic Screening; Genetic Transcription; Genetic study; Goals; Heat shock factor; Heterochromatin; Histones; Homeostasis; Huntington Disease; Hybrids; Light; Link; Maintenance; Malignant Neoplasms; Methods; Minor; Molecular; Morphology; Mutation; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Nuclear; Pathway interactions; Patients; Process; Production; Proteins; RNA interference screen; Research; Role; S-Adenosylmethionine; Site; Spinal; Spinal Cord; Stains; Structure; Structure of paramesonephric duct; System; Testing; Time; Tissues; Transferase; UBE2D2 gene; Ubiquitin; Ubiquitin-Conjugating Enzymes; Vertebrates; Yeasts; cell killing; cell type; chromatin remodeling; histone methylation; human disease; innovation; insight; live cell imaging; male; methionine adenosyltransferase; multicatalytic endopeptidase complex; mutant; new therapeutic target; novel; polyglutamine; programs; protein degradation; reproductive; tool; tumorigenesis; ubiquitin-protein ligase; yeast two hybrid system

Project Summary The long-term goal of the proposed research is to understand the cell biological mechanisms that execute non-apoptotic cell death. Programmed cell death is essential for organismal development and homeostasis, and its disruption is associated with many human diseases including cancer and neurodegeneration. Apoptosis is a prominent cell death form, however mutations in key apoptotic regulators only cause minor developmental defects. Non-apoptotic programs, therefore, also exist, but their molecular basis is poorly understood. Linker Cell-type Death (LCD) is a non-apoptotic and caspase-independent cell death process operating in C. elegans development, and its morphological hallmarks have also been observed in vertebrate development and disease. The Ubiquitin Proteasome System (UPS) is a key effector of LCD in C. elegans, but how it executes cell death is unknown. Here I will use powerful genetic and molecular tools in C. elegans to identify and characterize the proteolytic targets of the UPS during LCD and determine how their degradation trigger cell demise. In contrast to apoptosis, which uses caspases that transiently bind their substrates and, remarkably, remain poorly understood, the UPS stably interacts with its substrates. Therefore, the proteins I discover that precipitate cell death may unearth general mechanisms of cellular destruction that also function during apoptosis and disease. Indeed, our preliminary data suggest that one candidate substrate degraded by the UPS is an enzyme required for the maintenance of heterochromatin, which is in line with our previous observations that dying linker cells exhibit an open chromatin state. Therefore, this proposal will investigate the exciting hypothesis that chromatin remodeling, precipitated by the UPS, triggers cellular destruction. I will also discover additional proteolytic targets and mechanisms that execute non-apoptotic cell death with yeast 2-hybrid and RNAi screens. Because dysregulation of the UPS and chromatin state are also linked to tumorigenesis and neurodegenerative diseases, my studies can provide greater understanding of cell death programs disrupted in disease that can point towards new therapeutic targets.

项目摘要 拟议研究的长期目标是了解细胞生物学机制 执行非凋亡细胞死亡。程序性细胞死亡对于生物体发育至关重要 稳态及其中断与许多人类疾病有关，包括癌症和 神经变性。凋亡是一种突出的细胞死亡形式，但是关键凋亡调节剂中的突变 导致较小的发育缺陷。因此，非凋亡程序也存在，但它们的分子基础是 理解不佳。接头细胞型死亡（LCD）是一种非凋亡和caspase独立的细胞死亡过程 在秀丽隐杆线虫开发中运行及其形态学标志也已在脊椎动物中观察到 发展与疾病。泛素蛋白酶体系统（UPS）是秀丽隐杆线虫中LCD的关键效应子，但 它如何执行细胞死亡是未知的。在这里，我将在秀丽隐杆线虫中使用强大的遗传和分子工具 识别和表征LCD期间UPS的蛋白水解靶标的 降解触发细胞灭亡。与凋亡相反，凋亡使用caspase瞬时结合其 底物和显着的理解水平仍然很少，UPS与其底物稳定相互作用。所以， 我发现的蛋白质会沉淀细胞死亡可能会发现细胞破坏的一般机制， 在凋亡和疾病期间也起作用。确实，我们的初步数据表明一个候选底物 UPS降解是维持异染色质所需的酶，与我们的 先前的观察结果表明，垂死的接头细胞表现出开放的染色质状态。因此，该提议将 研究令人兴奋的假设，即染色质重塑，UPS沉淀，触发细胞 破坏。我还将发现执行非凋亡细胞的其他蛋白水解靶和机制 用酵母2杂交和RNAi筛选死亡。因为UPS和染色质状态的失调也是 与肿瘤发生和神经退行性疾病有关，我的研究可以提供对细胞的更多了解 疾病中断的死亡计划可能指向新的治疗靶标。