Mechanistic Studies of Ligand-Regulated Nuclear Receptor RXR Activity

配体调节核受体 RXR 活性的机制研究

• 批准号: 7502383
• 负责人: Yong Li
• 金额: $ 22.73万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-17 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7502383
• 关键词: Address; Adverse effects; Affinity; Amino Acid Receptors; Amino Acid Sequence; Binding; Binding Sites; Biochemical; Biological Assay; Biological Process; C-terminal; Cells; Chemicals; Clinical; Complex; Consensus; DNA; DNA Binding; DNA Binding Domain; DNA Structure; DNA-Protein Interaction; Development; Disease; Drug Delivery Systems; Elements; Family member; Foundations; Gene Targeting; Goals; Homeostasis; Human; Indium; Knowledge; Ligand Binding; Ligand Binding Domain; Ligands; Mediating; Metabolic; Metabolic Diseases; Metabolism; Modeling; Molecular; Mutation; N-terminal; Nuclear Receptors; Pathway interactions; Peroxisome Proliferator-Activated Receptors; Pharmaceutical Preparations; Physiological; Physiology; Proteins; Public Health; RXR; Range; Receptor Gene; Regulation; Relative (related person); Reporting; Research; Response Elements; Retinoids; Role; Signal Transduction; Site; Specificity; Structure; Testing; Therapeutic Uses; Thyroid Hormones; Toxic effect; Validation; Vitamin A; Vitamin D; X-Ray Crystallography; alitretinoin; base; cofactor; cross reactivity; design; drug discovery; human disease; improved; insight; intermolecular interaction; multidisciplinary; receptor; receptor binding; response; three dimensional structure

DESCRIPTION (provided by applicant): The goal of our research is to unravel the molecular basis of the nuclear receptor actions using X-ray crystallography in conjunction with multidisciplinary molecular and biochemical approaches. The nuclear receptor retinoid X receptors (RXRs) are key ligand-activated transcriptional regulators involved in a wide range of human physiology, including development and metabolism. RXRs are well-established drug targets. However, the clinical use of RXR ligands is clearly tempered by side effects like toxicity, possibly associated with their low selectivity and affinity and also the cross-reactivity with other functions of RXRs. To understand the molecular basis of ligand-mediated signaling of RXRs in human physiology, we are planning to determine the crystal structures of a RXR multi-domain fragment bound to a DNA response fragment of their target genes. Following structure determination, we will perform mutational studies, biochemical analysis, and cell-based transcriptional assays to confirm functional significance of key structure elements. This study will reveal the molecular basis of the functional specificity of RXRs and its ligands at key regulatory steps: from ligand binding and to target gene recognition. The structural insights will provide a rational template for structure-based drug discovery of highly selective and efficient RXR ligands with reduced side effects for the therapeutic use in human disease. Moreover, the structure generated in this project will serve as a model to study the ligand-dependent regulation of other nuclear receptor family members. PUBLIC HEALTH RELEVANCE: This proposal addresses a critical need in the current nuclear receptor research by providing three-dimensional structures of the multi-domain retinoid X receptor bound to its target genes. The structural and functional studies will reveal detailed insights on how drug specificity and affinity can be further improved, thus providing a foundation for rational drug discovery for effective treatment of human disease like metabolic disease.

描述（由申请人提供）：我们研究的目标是使用X射线晶体学结合多学科分子和生物化学方法来阐明核受体作用的分子基础。核受体类维生素A X受体（RXR）是参与广泛的人类生理学（包括发育和代谢）的关键配体激活的转录调节因子。RXR是公认的药物靶标。然而，RXR配体的临床使用明显受到副作用如毒性的影响，这可能与它们的低选择性和亲和力以及与RXR的其他功能的交叉反应性有关。为了了解RXR在人体生理学中配体介导的信号传导的分子基础，我们计划确定与其靶基因的DNA反应片段结合的RXR多结构域片段的晶体结构。结构确定后，我们将进行突变研究，生化分析和基于细胞的转录测定，以确认关键结构元件的功能意义。这项研究将揭示RXR及其配体在关键调控步骤的功能特异性的分子基础：从配体结合到靶基因识别。结构的见解将提供一个合理的模板，为基于结构的药物发现的高度选择性和有效的RXR配体与减少的副作用，用于人类疾病的治疗用途。此外，在这个项目中产生的结构将作为一个模型，研究其他核受体家族成员的配体依赖性调节。公共卫生相关性：这一提议通过提供与其靶基因结合的多结构域维甲酸X受体的三维结构来解决当前核受体研究中的关键需求。结构和功能研究将揭示如何进一步提高药物特异性和亲和力的详细见解，从而为合理的药物发现提供基础，以有效治疗人类疾病，如代谢疾病。