Characterizing Stress-dependent Secretory Protein Mistargeting

表征压力依赖性分泌蛋白误定位

• 批准号: 10660460
• 负责人: Joseph Genereux
• 金额: $ 31.08万
• 依托单位: UNIVERSITY OF CALIFORNIA RIVERSIDE
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2028-02-29
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10660460
• 关键词: ATF6 gene; Affinity; Biochemical; Biological Assay; Biology; Cell Culture Techniques; Cell Death; Cells; Cessation of life; Chemicals; Client; Coupled; Cytosol; Development; Diabetes Mellitus; Disease; Endoplasmic Reticulum; Experimental Designs; Foundations; Functional disorder; Health; Heat shock proteins; Human; Impairment; Individual; Intervention; Investigation; Label; Location; Maintenance; Mass Spectrum Analysis; Measures; Mediating; Membrane Proteins; Methodology; Modeling; Molecular Conformation; Neurodegenerative Disorders; Outcome; Pathway interactions; Physiological; Post-Translational Protein Processing; Predisposition; Process; Protein translocation; Proteins; Proteome; Proteomics; Quality Control; Reporting; Research; Research Personnel; Role; Route; Secretory Cell; Series; Signal Pathway; Stress; System; Triage; Ubiquitin; biological adaptation to stress; cell type; endoplasmic reticulum stress; experience; misfolded protein; multicatalytic endopeptidase complex; new technology; non-Native; novel; prevent; proteostasis; proteotoxicity; response; secretory protein; sensor; stressor

PROJECT SUMMARY The secretory pathway must fold and traffic one third of the proteome, while handling an exceptional dynamic range of client load. Quality control mechanisms prevent proteostasis in the secretory pathway from being overwhelmed by proteins in non-native states. One such mechanism is preemptive quality control (preQC), wherein ER stress inhibits ER translocation of nascent proteins. This process protects the ER from being overwhelmed with nascent protein during misfolded protein stress, a situation associated with diverse disease included diabetes and neurodegenerative diseases. However, this protection leads to secretory protein accumulating in the cytosol, which can be proteotoxic and lead to cell death and dysfunction. Due to methodological limitations, the substrates, causes, mechanism, and consequences of preQC are largely unknown. Hence, the physiological relevance of preQC, while expected to be significant, is not well understood. We propose to apply our recently developed assay for secretory protein mistargeting to systematically characterize preQC. We will identify which stresses induce preQC for a series of protein substrates in secretory cells from diverse human lineages. We will identify what factors govern triaging of mistargeted secretory proteins between aggregation and degradation mechanisms. Because our assay is performed in living cells, we will determine which signaling pathways mediate induction of preQC by ER stress. Finally, we will extend our assay to allow proteome-wide quantification of both basal and stress-dependent ER mistargeting. This extension will allow us to identify the factors that govern susceptibility of proteins to preQC. The outcome of the proposed research will be systematic characterization of how the cell remodels ER translocation in response to stress.

项目摘要 分泌途径必须折叠并交通蛋白质组的三分之一，同时处理 客户负载的非凡动态范围。质量控制机制阻止了蛋白质的 分泌途径是在非本地状态下被蛋白质淹没的途径。一个这样的 机制是先发制人的质量控制（PREQC），其中ER应力抑制ER的易位 新生蛋白。此过程可保护ER免于被新生蛋白淹没 在错误折叠的蛋白质胁迫期间，与多种疾病有关的情况包括糖尿病和 神经退行性疾病。但是，这种保护导致分泌蛋白在 可蛋白毒性并导致细胞死亡和功能障碍的细胞质。由于 PREQC的方法论局限性，基材，原因，机制和后果是 在很大程度上未知。因此，PREQC的生理相关性，虽然预计会很重要，但 不太了解。我们建议将我们最近开发的分泌蛋白应用于分泌蛋白 误导系统地表征preqc。我们将确定哪些应力诱导Preqc 对于来自不同人类谱系的分泌细胞中的一系列蛋白质底物。我们将确定 哪些因素控制着聚集和 退化机制。因为我们的测定是在活细胞中进行的，所以我们将确定哪个 信号通路通过ER应力介导PREQC的诱导。最后，我们将把测定法扩展到 允许对基础和应力依赖性ER误导的全蛋白质组定量。这 扩展将使我们能够确定控制蛋白质对PREQC的敏感性的因素。这 拟议研究的结果将是细胞重塑的系统表征 响应压力的ER易位。