Structural Biology of Multi-Domain Nuclear Receptor Complexes

多域核受体复合物的结构生物学

• 批准号: 9159659
• 负责人: FRAYDOON RASTINEJAD
• 金额: $ 38.27万
• 依托单位: SANFORD BURNHAM PREBYS MEDICAL DISCOVERY INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-06-01 至 2021-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9159659
• 关键词: Architecture; Binding; Biochemical; Biological Assay; Cells; Communication; Complex; Coupling; Crystallization; DNA; DNA Binding; DNA Binding Domain; Developmental Process; Dietary Fats; Direct Repeats; Drug Prescriptions; Elements; Embryonic Development; Family; Fatty Acids; Fertility; Gene Expression; Genetic Transcription; Heme; Human; Individual; Lead; Learning; Length; Ligand Binding; Ligand Binding Domain; Ligands; Link; Mediating; Metabolism; Molecular; N-terminal; Nuclear Receptors; PPAR gamma; Pathway interactions; Peptides; Physiological; Progesterone Receptors; Property; RXR; Reporting; Reproductive Process; Response Elements; Retinoic Acid Receptor; Retinoic Acid Response Element; Retinoids; Series; Signal Transduction; Site; Steroid Receptors; Steroids; Structure; Surface; X ray diffraction analysis; X-Ray Diffraction; base; lipid metabolism; lipophilicity; monomer; polypeptide; progesterone receptor A; programs; protein complex; receptor; receptor binding; receptor function; response; small molecule; steroid hormone; structural biology; transcription factor

PROJECT SUMMARY Lipophilic molecules including steroid hormones, retinoids, fatty acids, and dietary lipids control reproductive, developmental and metabolic processes by directly binding and modulating the activities of nuclear receptors (NRs). NRs bind to DNA and regulate the expression of gene programs that lead to physiological responses to their small-molecule ligands. Structural studies over the past few decades have focused primarily on just the ligand binding domains (LBDs) or DNA-binding domains (DBDs) of NRs, but were unable to reveal how the multi-domain architectures are integrated in a quaternary structure. To understand the physical and functional coupling of different receptor domains, we have been conducting X-ray diffraction studies involving full-length and multi-domain nuclear receptor complexes in their functionally revealing complexes bound to DNA, ligands, and coregulator peptides. Our previous studies revealed that DBDs and LBDs of the PPARγ-RXRα heterodimer and HNF-4α homodimer are physically linked through a highly interfaced arrangement of domain surfaces, some of which are DNA-dependent. We now propose to considerably broaden our understanding of the domain-domain connections and allosteric communications in the nuclear receptor family. We will obtain the crystal structures of three new NR complexes that include the Retinoic-Acid Receptor (RAR) heterodimer with Retinoid X Receptor (RXR), the progesterone receptor (PR) homodimer, and the monomeric Rev-Erbβ receptor. These differing NRs also discern distinct response elements consisting of direct repeats, inverted repeats, and single half-sites, thus, distinctive domain-domain interfaces are anticipated as compared to previously seen in PPARγ-RXRα or HNF-4α. We further propose to conduct a series of complementary biochemical and cell-based functional studies to probe and quantitate the mechanistic underpinning of inter- domain allosteric signal propagation in these receptor complexes.

项目概要 亲脂性分子包括类固醇激素、类维生素A、脂肪酸和饮食脂质，控制生殖、 通过直接结合和调节核受体的活性来调节发育和代谢过程 （NR）。 NR 与 DNA 结合并调节基因程序的表达，从而导致生理反应 它们的小分子配体。过去几十年的结构研究主要集中在 NR 的配体结合域（LBD）或 DNA 结合域（DBD），但无法揭示如何 多域架构集成在四元结构中。了解物理和功能 不同受体结构域的耦合，我们一直在进行涉及全长的 X 射线衍射研究 和多结构域核受体复合物，其功能揭示了与 DNA、配体结合的复合物， 和共调节肽。我们之前的研究表明 PPARγ-RXRα 的 DBD 和 LBD 异二聚体和 HNF-4α 同二聚体通过结构域的高度界面排列进行物理连接 表面，其中一些是 DNA 依赖性的。我们现在建议大大拓宽我们对 核受体家族中的域-域连接和变构通信。我们将获得 包括视黄酸受体 (RAR) 异二聚体在内的三种新型 NR 复合物的晶体结构 含有类视黄醇 X 受体 (RXR)、孕酮受体 (PR) 同二聚体和单体 Rev-Erbβ 受体。这些不同的 NR 还可以识别不同的响应元素，包括直接重复、反向重复 重复和单个半位点，因此，与 之前曾在 PPARγ-RXRα 或 HNF-4α 中看到过。我们进一步建议开展一系列补充性活动 生化和基于细胞的功能研究，以探测和定量相互作用的机制基础 这些受体复合物中的结构域变构信号传播。