EUKARYOTIC CHAPERONIN

真核伴侣蛋白

• 批准号: 8168533
• 负责人: JUDITH FRYDMAN
• 金额: $ 4.3万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-01-15 至 2010-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8168533
• 关键词: ATP Hydrolysis; Actins; Adopted; Alzheimer' s Disease; Binding; Biochemical; Cell division; Cells; Collaborations; Complement; Complex; Computer Retrieval of Information on Scientific Projects Database; Cryoelectron Microscopy; Cyclin E; Disease; Funding; Grant; Hydrolysis; Institution; Knowledge; Light; Malignant Neoplasms; Mediating; Mediator of activation protein; Methods; Molecular; Molecular Chaperones; Molecular Conformation; Prion Diseases; Proteins; Reaction; Research; Research Personnel; Resources; Roentgen Rays; Shapes; Source; Staging; Stress; Structure; Tubulin; United States National Institutes of Health; Von Hippel-Lindau Tumor Suppressor Protein; analog; base; chaperonin; protein folding; protein function

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Molecular chaperones are key mediators of cellular folding. The eukaryotic chaperonin TRiC/CCT is essential to fold a wide array of cellular proteins. Its substrates include key proteins essential for cell division, such as actin, tubulin, cyclin E and the tumor suppressor protein VHL. TRiC is a 1 MDa ring-shaped hetero-oligomeric complex that uses ATP-binding and hydrolysis to drive the folding cycle. It is composed of 2 rings containing 8 different but highly similar subunits in each ring. Little is known about the conformational changes that accompany ATP-binding and hydrolysis. We have recently carried out biochemical and biophysical studies to characterize its conformational cycle. The structural analysis by cryoEM will provide a critical complement to the biochemical analysis. Biomedical relevance of the study: Recent findings indicating that misfolding and accumulation of incorrectly folded proteins is the molecular basis of many diseases, including cancer, Alzheimer's and Prion Diseases, underscore the importance of understanding the mechanisms of chaperone-mediated folding. Thus, knowledge of how chaperones function to promote folding in the cell should eventually provide the basis for controlling protein function under normal conditions, and during abnormal conditions of environmental stress and disease. TRiC is a ATP-dependent chaperonin with a built-in lid. Our preliminary results using biochemical methods and Small Angle X-ray Scattering indicate changes in ATP during the hydrolysis cycle drive the closing and opening of the lid. The collaboration with NCMI will shed light on the conformation adopted by TRiC during the ATP hydrolysis cycle. Using analogues of ATP that mimic distinct stages of the ATP hydrolysis reaction, we will detect the conformational changes that drive chaperonin-mediated folding. In a separate suite of studies, we will also investigate the structure of the TRiC-bound substrate. These studies will be an ideal complement to our mechanistic biochemical and biophysical studies.

该副本是利用众多研究子项目之一 由NIH/NCRR资助的中心赠款提供的资源。子弹和 调查员（PI）可能已经从其他NIH来源获得了主要资金， 因此可以在其他清晰的条目中代表。列出的机构是 对于中心，这不一定是调查员的机构。 分子伴侣是细胞折叠的关键介体。真核生物伴侣蛋白Tric/CCT对于折叠多种细胞蛋白是必不可少的。它的底物包括对细胞分裂必不可少的关键蛋白，例如肌动蛋白，微管蛋白，细胞周期蛋白E和肿瘤抑制蛋白VHL。 TRIC是一种1 MDA环形杂极复合物，它使用ATP结合和水解来驱动折叠周期。它由2个环组成，其中包含每个环中的8个不同但高度相似的亚基。关于ATP结合和水解伴随的构象变化知之甚少。 我们最近进行了生化和生物物理研究，以表征其构象周期。 Cryoem的结构分析将为生化分析提供关键补充。 研究的生物医学相关性：最近的发现表明，错误折叠蛋白的错误折叠和积累是许多疾病的分子基础，包括癌症，阿尔茨海默氏症和prion疾病，强调了了解伴侣介导的折叠机制的重要性。因此，了解伴侣如何促进细胞折叠的知识最终应为在正常条件下以及在环境压力和疾病的异常条件下控制蛋白质功能提供基础。 Tric是带有内置盖的ATP依赖性伴侣蛋白。我们使用生化方法和小角度X射线散射的初步结果表明，在水解周期期间，ATP的变化驱动了盖子的关闭和打开。与NCMI的合作将阐明Tric在ATP水解周期中采用的构象。使用ATP的类似物，模仿ATP水解反应的不同阶段，我们将检测到构象变化，从而驱动伴侣蛋白介导的折叠。在另一套研究中，我们还将研究三合会结合底物的结构。这些研究将是我们机械生化和生物物理研究的理想补充。