Project 3: Structural Basis for grp94 Drug Development and Chaperone Function

项目3：grp94药物开发和伴侣功能的结构基础

• 批准号: 8934515
• 负责人: DANIEL T GEWIRTH
• 金额: $ 34.71万
• 依托单位: MEDICAL UNIVERSITY OF SOUTH CAROLINA
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8934515
• 关键词: ATP Hydrolysis; Address; Adverse effects; Affinity; Amino Acids; Binding; Biochemical; Cancer Biology; Cells; Chemicals; Cleaved cell; Client; Collaborations; Complex; Data; Development; Drug Design; Elements; Endoplasmic Reticulum; Exhibits; Family; Fostering; Generations; Goals; Heat-Shock Proteins 90; In Vitro; Individual; Knowledge; Lead; Ligands; Malignant Neoplasms; Metabolic; Modification; Molecular Chaperones; Molecular Conformation; N Domain; N-terminal; Oncogenic; Play; Post-Translational Modification Site; Post-Translational Protein Processing; Property; Proteins; Purines; Role; Route; Site; Structure; Testing; Therapeutic; Thermodynamics; Work; anti-cancer therapeutic; base; cancer therapy; design; drug development; glycosylation; improved; in vivo; inhibitor/antagonist; mutant; next generation; novel; novel therapeutics; paralogous gene; purine; research study; response; three dimensional structure

PROJECT SUMMARY Grp94 is an ER HSP90 chaperone whose broad oncogenic roles have only recently been established. However, understanding of grp94 structure and mechanism has lagged behind that of other HSP90s. grp94 exhibits high sequence and structural homology to the other cellular HSP90 paralogs. Nevertheless, attempts to demonstrate complementation between the cytosolic and ER paralogs have consistently failed in both directions, suggesting that the enormous metabolic burden of maintaining high levels of a specialized ER- specific HSP90 has a distinct mechanistic purpose. We propose that this distinct mechanism is reflected in its structure. The goal of this project is to understand what makes grp94 unique in the HSP90 family and to exploit these features in the design of new inhibitors as cancer therapeutics. We will address this question in four specific aims. The first is to characterize and develop next-generation grp94-selective inhibitors. Together with Dr. Gabriela Chiosis, leader of Project 2, we have characterized a set of purine-based (PU) compounds that bind selectively to grp94 and exhibit anti-cancer activity. Higher affinity and more selective compounds are needed to improve their therapeutic potential and to serve as chemical probes of grp94 function. The second is to determine the structural basis for selective binding of PU ligands to grp94. We will investigate how the conformational changes in grp94 that foster selective inhibitor binding manage to occur in one paralog and not another – what specific sequence and structural elements make the grp94 response distinct? Third, we aim to determine how individual structural domains contribute to the unique biochemical and functional properties of grp94. In collaboration with Dr. Zihai Li, leader of Project 1, we will examine how individual grp94 domains contribute to the overall specialization and function of this paralog as it matures its client proteins such as GARP. Fourth, we will probe the role of post-translational modifications (PTMs) on grp94 client binding and activity. Together these experiments should pave the way for the development of new anti-cancer therapeutics and illuminate central mechanistic questions about grp94 action.

项目摘要 GRP94是ER HSP90伴侣，直到最近才建立了广泛的致癌作用。 但是，对GRP94结构和机制的理解落后于其他HSP90。 GRP94 表现出与其他细胞HSP90旁系同源物的高序列和结构同源性。然而，尝试 为了证明胞质和ER旁系同源物之间的完成始终失败 方向，表明维持高水平的专业ER-代谢燃烧 特定的HSP90具有独特的机械目的。我们建议这种独特的机制反映在其 结构。该项目的目的是了解是什么使GRP94在HSP90家族中与众不同并利用 这些特征是设计新抑制剂作为癌症疗法的特征。我们将在四个中解决这个问题 具体目标。首先是表征和发展下一代GRP94选择性抑制剂。一起 项目2的负责人Gabriela Chiosis博士表征了一套基于购买的（PU）化合物 选择性结合GRP94并暴露于抗癌活性。更高的亲和力和更有选择的化合物是 需要提高其治疗潜力并充当GRP94功能的化学问题。第二个是 确定PU配体与GRP94选择性结合的结构基础。我们将调查如何 GRP94中构象变化，促进选择性抑制剂结合的构造是在一个旁系同源物中发生的，而不是发生 另一个 - 哪些特定序列和结构元素使GRP94响应不同？第三，我们的目标是 确定单个结构域如何促进独特的生化和功能特性 GRP94。与项目1的负责人Zihai Li博士合作，我们将研究单个GRP94领域 在该旁系同源物的整体专业化和功能中促进其客户蛋白（例如 加普。第四，我们将探讨翻译后修改（PTM）在GRP94客户端绑定和 活动。这些实验应该为开发新的抗癌疗法铺平道路 并阐明了有关GRP94动作的中心机械问题。