Structural Studies of cullin-based ubiquitin ligases

基于 cullin 的泛素连接酶的结构研究

• 批准号: 8235075
• 负责人: NING ZHENG
• 金额: $ 29.44万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-05-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8235075
• 关键词: Adaptor Signaling Protein; Address; Agonist; Antineoplastic Agents; Auxins; BTB/POZ Domain; Biochemical; Biology; Cell Nucleus; Cell physiology; Complex; Cullin Proteins; Cytosol; DNA Repair; DNA biosynthesis; Disease; Docking; Drug Delivery Systems; Enzymes; Eukaryotic Cell; F-Box Proteins; Family; Foundations; Funding; Future; Genome; Health; Hormone Receptor; Hormones; Human; Human Genome; IL27RA gene; JUN gene; Length; Ligase; Link; Malignant Neoplasms; Mediating; Molecular; Organism; Oxidative Stress; Perception; Physiological; Plant Growth Regulators; Plant Physiology; Plants; Polyubiquitin; Polyubiquitination; Proteins; Proteomics; Publishing; Recruitment Activity; Regulation; Role; Signal Transduction; Structure; System; Ubiquitin; Ubiquitination; Variant; Virus Diseases; base; biological adaptation to stress; cell growth regulation; dimer; human disease; inhibitor/antagonist; jasmonate; nervous system disorder; novel; protein function; receptor; response; scaffold; sensor; small molecule; structural biology; transcription factor; tumorigenesis; ubiquitin ligase; ubiquitin-protein ligase

DESCRIPTION (provided by applicant): The cullin-RING ligases (CRLs) represent the largest super-family of multi-subunit E3 ubiquitin ligase complexes in eukaryotic cells. Organized in a modular form with a cullin-RING catalytic scaffold, an adaptor, and an interchangeable substrate-receptor subunit, the CRL1-5 complexes regulate a wide variety of cellular processes by promoting ubiquitination of a large number of protein substrates. Dysregulation and malfunction of CRLs are implicated in tumorigenesis, cancers, and a variety of other human diseases. This project focuses on structure-function studies of several CLR complexes in the regulation of cell growth, DNA replication, DNA repair, oxidative stress response, and hormone perception. In Aim1, a structural biology approach will be used to investigate how the substrate receptor subunits (DCAFs) of a newly identified family of CLRs, the CRL4 E3 complexes, are recruited to the ubiquitin ligase machinery. This study is aimed at resolving the current controversy over the identity of the CRL4 substrate receptors among all WD40-repeat proteins in the human genome. In Aim 2, a combination of biochemical and structural biology approaches will be employed to analyze the structural and functional roles of a novel functional ubiquitin E3 variant protein in the CRL4-Det1 E3 complex, which ubiquitinates the bZIP family of transcription factors such as c-Jun. In Aim 3, the crystal structure of the full length Keap1 dimer will be determined to elucidate how the BTB-domain protein functions as an oxidative stress sensor as well as a dimeric substrate receptor subunit of the CRL3 E3 complex. In Aim 4, the structural mechanism by which the plant COI1 F-box protein functions as the jasmonate plant hormone receptor will be investigated. Together with the recently published results of how another plant F-box protein TIR1 recognizes the plant hormone auxin, this study is aimed at establishing the structural principles of how these naturally occurring small molecules regulate the CRL E3s as agonists and laying the foundation of ongoing and future efforts of developing anti-cancer drugs targeting human CRLs. PUBLIC HEALTH RELEVANCE Tumorigenesis, cancer, and a variety of other human diseases including neurological disorders and viral infections are associated with the abnormal functions of a newly identified family of enzymatic complexes, known as the cullin-RING ubiquitin ligases. This proposal is aimed at studying the structural basis of how these enzyme machineries assemble and function in human and other organisms so that new strategies can be derived to develop novel drugs targeting this disease-associated enzymes.

描述（由申请人提供）：cullin-RING 连接酶（CRL）代表真核细胞中最大的多亚基 E3 泛素连接酶复合物超家族。 CRL1-5 复合物以模块化形式组织，具有 cullin-RING 催化支架、接头和可互换的底物受体亚基，通过促进大量蛋白质底物的泛素化来调节多种细胞过程。 CRL 的失调和功能障碍与肿瘤发生、癌症和多种其他人类疾病有关。该项目重点研究几种 CLR 复合物在细胞生长、DNA 复制、DNA 修复、氧化应激反应和激素感知调节中的结构功能研究。在 Aim1 中，结构生物学方法将用于研究新鉴定的 CLR 家族（CRL4 E3 复合物）的底物受体亚基 (DCAF) 如何被招募到泛素连接酶机制中。本研究旨在解决目前关于人类基因组中所有 WD40 重复蛋白中 CRL4 底物受体身份的争议。在目标 2 中，将采用生化和结构生物学方法相结合来分析 CRL4-Det1 E3 复合物中新型功能性泛素 E3 变体蛋白的结构和功能作用，该复合物泛素化 bZIP 转录因子家族（例如 c-Jun）。在目标 3 中，将确定全长 Keap1 二聚体的晶体结构，以阐明 BTB 结构域蛋白如何充当氧化应激传感器以及 CRL3 E3 复合物的二聚体底物受体亚基。在目标4中，将研究植物COI1 F-box蛋白作为茉莉酸植物激素受体的结构机制。结合最近发表的另一种植物 F-box 蛋白 TIR1 如何识别植物激素生长素的结果，本研究旨在建立这些天然存在的小分子如何作为激动剂调节 CRL E3 的结构原理，并为当前和未来开发针对人类 CRL 的抗癌药物奠定基础。公共健康相关性肿瘤发生、癌症和各种其他人类疾病（包括神经系统疾病和病毒感染）与新发现的酶复合物家族（称为 cullin-RING 泛素连接酶）的异常功能有关。该提案旨在研究这些酶机器在人类和其他生物体中如何组装和发挥作用的结构基础，以便得出新的策略来开发针对这种与疾病相关的酶的新药物。