Engagement and Communication Between Proteasomal Subcomplexes

蛋白酶体亚复合物之间的参与和通讯

• 批准号: 10659372
• 负责人: ROBERT JOSEPH TOMKO
• 金额: $ 30.16万
• 依托单位: FLORIDA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-01 至 2027-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10659372
• 关键词: 26S proteasome; ATP phosphohydrolase; Animals; Architecture; Area; Autoimmune Diseases; Autophagocytosis; Binding; Biogenesis; Biological Assay; Biology; Budgets; Catalysis; Cells; Communicable Diseases; Communication; Complement; Complex; Conserved Sequence; Coupled; Cytoprotection; Dedications; Diabetes Mellitus; Disease; Dissociation; Distant; Drug Targeting; Elements; Equilibrium; Eukaryota; Event; Excision; Family; Fluorescence Resonance Energy Transfer; Goals; Health; Hot Spot; Human; Infection; Kinetics; Knowledge; Ligand Binding; Ligands; Link; Malignant Neoplasms; Mediating; Microsporidia; Modeling; Molecular; Molecular Chaperones; Molecular Conformation; Movement; Mutation; Nerve Degeneration; Neurodegenerative Disorders; Nucleosome Core Particle; Parasites; Parasitic infection; Pharmaceutical Preparations; Process; Proteins; Proteolysis; Quality Control; Reagent; Recycling; Role; Route; Signal Transduction; Site; Structure; Testing; Tyrosine; United States National Institutes of Health; Work; Yeasts; anti-cancer; base; combat; conformational conversion; design; drug discovery; effective therapy; flexibility; guided inquiry; human disease; human pathogen; in vivo; inhibitor; insight; interest; multicatalytic endopeptidase complex; novel; novel therapeutics; priority pathogen; protein degradation; tool; transmission process

Project Summary Abstract The 26S proteasome conducts most regulated protein degradation and eliminates toxic proteins from cells. The proteasome is a validated anti-cancer target, and holds substantial promise as a target for treatment of neurodegenerative disorders and some infectious diseases. Our long-term goal is to understand how the three major complexes of the proteasome—the lid, base, and core particle—engage and communicate within and between one another. We have thus far made significant progress toward this goal and have developed a number of novel tools and reagents that have furthered our understanding of intra- and inter-complex communication. Conceptual advances have included: i) discovery of additional conformational states of the yeast proteasome relevant to substrate catalysis; ii) demonstration that six highly similar ATP-hydrolyzing subunits differentially influence the activation state of the proteasome; iii) discovery of a link between the conformational state of the proteasome and release of a dedicated proteasome assembly chaperone; and iv) and the finding that proteasomal subcomplexes disengage one another prior to their destruction by autophagy. A paradigm emerging from this initial budget period is that rather small binding events or molecular movements are transmitted, often over long distances, to enact largescale conformational changes. Understanding how such local events are amplified and transmitted to distant areas of the proteasome to coordinate assembly and catalysis is thus a critical knowledge gap. In this first renewal, we propose three Aims that explore examples of this paradigm newly discovered by us during the initial budget period. Together, they will push our knowledge of proteasome dynamics and inter-complex communication into new arenas. In the first, we will use newly developed FRET-based kinetic assays to decipher how local changes to the lid-base interface regulate the timely binding and release of dedicated assembly chaperones from nascent proteasomes. In the second, we will explore a surprising allosteric conduit originating from the substrate unfolding center of the proteasome that regulates the stability between two key subcomplexes. In the third Aim, we will investigate an unusual eukaryotic proteasome from a poorly studied human parasite from the phylum of Microsporidia. Microsporidia lack several proteasome subunits that normally span a key inter-complex interface. The missing subunits contain several small sequence elements with essential roles in assembly and catalysis in other eukaryotes, so exploring these unusual proteasomes will thus reveal both conserved and unique elements of inter-complex communication. These studies are anticipated to produce important insights into the engagement and communication between the proteasomal subcomplexes, significantly advancing several aspects of proteasome biology and drug discovery. Further, microsporidia are NIH priority pathogens of interest for which no broadly effective treatments exist. Insights into microsporidial proteasomes thus may reveal new targets to combat certain parasitic infections.

项目概要摘要 26S 蛋白酶体进行最受调节的蛋白质降解并消除细胞中的有毒蛋白质。 蛋白酶体是一种经过验证的抗癌靶标，并具有作为治疗癌症的靶标的巨大前景 我们的长期目标是了解这三者之间的关系。 蛋白酶体的主要复合物——盖子、基底和核心颗粒——在内部参与和交流 迄今为止，我们已在实现这一目标方面取得了重大进展，并制定了多项计划。 一系列新的工具和试剂进一步加深了我们对复合体内部和复合体间通讯的理解。 概念性进展包括：i) 发现酵母蛋白酶体的其他构象状态 与底物催化相关；ii) 证明六个高度相似的 ATP 水解亚基存在差异 影响蛋白酶体的激活状态；iii) 发现蛋白酶体的构象状态之间的联系。 蛋白酶体和专用蛋白酶体组装伴侣的释放；以及 iv) 以及以下发现： 蛋白酶体亚复合物在被自噬破坏之前彼此脱离。 从这个初始预算期出现的一个范式是相当小的结合事件或分子运动 通常是长距离传输，以实现大规模的构象变化。 局部事件被放大并传输到蛋白酶体的远处区域以协调组装和 因此，催化是一个关键的知识差距，在第一次更新中，我们提出了三个目标来探索示例。 我们在最初的预算期间新发现的这一范式将共同推动我们的知识。 首先，我们将使用新的蛋白酶体动力学和复合物间通讯。 开发了基于 FRET 的动力学测定，以破译盖基界面的局部变化如何及时调节 在第二步中，我们将结合和释放新生蛋白酶体中的专用组装伴侣。 探索源自蛋白酶体底物展开中心的令人惊讶的变构导管， 调节两个关键子复合体之间的稳定性在第三个目标中，我们将研究一种不寻常的真核生物。 来自微孢子虫门的一种未经充分研究的人类寄生虫的蛋白酶体缺乏几种。 通常跨越关键复合物间界面的蛋白酶体亚基包含几个缺失的亚基。 在其他真核生物的组装和催化中具有重要作用的小序列元件，因此探索这些 因此，不寻常的蛋白酶体将揭示复合物间通讯的保守且独特的元素。 预计这些研究将对人与人之间的参与和沟通产生重要的见解。 蛋白酶体亚复合物，显着推进了蛋白酶体生物学和药物的多个方面 此外，微孢子虫是 NIH 重点关注的病原体，目前尚无广泛有效的治疗方法。 因此，对微孢子蛋白酶体的深入了解可能会揭示对抗某些寄生虫感染的新靶标。