Nuclear receptors: action, functions, and roles in disease

核受体：在疾病中的作用、功能和作用

• 批准号: 8734135
• 负责人: Anton M Jetten
• 金额: $ 119.77万
• 依托单位: NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH SCIENCES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8734135
• 关键词: AF2; Adipose tissue; Adult; Affect; Agonist; Antibodies; Asthma; Ataxia-Telangiectasia-Mutated protein kinase; Autoimmune Diseases; Behavior; Bile Acids; CD44 gene; Cell Differentiation process; Cell physiology; Cerebellum; Circadian Rhythms; Cystic Kidney Diseases; Cytochrome P450; Cytoplasmic Granules; DNA Damage; DNA Maintenance; DNA Repair; Data; Development; Diabetes Mellitus; Diet; Disease; Down-Regulation; Embryonic Development; Environment; Enzymes; Estrogen Receptor 1; Estrogen Receptor alpha; Exhibits; Experimental Autoimmune Encephalomyelitis; Fatty Liver; Fibrosis; Gene Expression; Gene Expression Regulation; Gene Targeting; Generations; Genes; Genetic Transcription; Genome; Genome Stability; Genomic Instability; Glucose Intolerance; Homeostasis; Human Pathology; Hydroxysteroid Dehydrogenases; Immune system; Immunity; In Vitro; Infiltration; Inflammation; Insulin Resistance; Knockout Mice; Laboratories; Ligand Binding Domain; Ligands; Link; Lipids; Liver; Liver diseases; Lobule; Lymphoma; MAP3K7 gene; MDM2 gene; Malignant Neoplasms; Mammary gland; Mediating; Metabolic; Metabolic Control; Metabolic Pathway; Metabolic syndrome; Metabolism; Microarray Analysis; Modeling; Molecular Profiling; Multiple Sclerosis; Mus; Neuroglia; Neurons; Non-Insulin-Dependent Diabetes Mellitus; Nuclear Orphan Receptor; Nuclear Protein; Nuclear Receptors; Obesity; Organogenesis; Orphan; Pathology; Pattern; Phase; Phenotype; Phosphorylation; Physiological; Physiological Processes; Play; Polyubiquitination; Predisposition; Protein p53; Proteins; Purkinje Cells; Radial; Regulation; Reporting; Repression; Resistance; Response Elements; Retinoids; Role; Signal Pathway; Signal Transduction; Site; Staggerer Mouse; Therapeutic; Tissues; Transcriptional Activation; Transcriptional Regulation; Tumor Suppressor Proteins; UV induced; Ubiquitin; Xenobiotics; Yeasts; allergic airway disease; cancer risk; circadian pacemaker; dimethylbenzanthracene; fibrogenesis; functional genomics; gene environment interaction; lymph nodes; macrophage; malignant breast neoplasm; member; neurobehavioral; novel; novel therapeutics; obesity management; promoter; protein complex; receptor; receptor function; response; steroid metabolism; sulfotransferase; therapeutic target; thymocyte; transcription factor; tumor; tumorigenesis; ubiquitin-protein ligase; ultraviolet irradiation; yeast two hybrid system

I. RORalpha and gamma: The retinoid-related orphan receptor a and g (RORa and RORg) are members of the nuclear receptor superfamily. To identify the physiological functions of RORa and g, mice deficient in RORa and g function were analyzed. RORg exhibit several functions in the immune system. RORg expression is indispensable for lymph node organogenesis and plays a critical role in thymocyte homeostasis. Recently a role for RORg in Th17 cell differentiation was identified. We demonstrated that both RORa and RORg are induced during Th17 cells differentiation and double knockouts mice are resistant to experimental autoimmune encephalomyelitis, a model for multiple sclerosis. In addition, RORg-deficient mice are less susceptible to aovalbumin (OVA)-induced inflammation in mice, a model for allergic airway disease. Retinoid-related orphan receptors alpha (RORa) and gamma (RORg) are both expressed in liver; however, their physiological functions in this tissue have not yet been clearly defined. RORa1 and RORg1 show an oscillatory pattern of expression during circadian rhythm. Comparison of gene expression profiles of livers from WT, RORa-deficient staggerer mice (RORasg/sg), RORg-/-, and RORasg/sgRORg-/- double knockout (DKO) mice by microarray analysis demonstrated that RORa and RORg are particularly important in the regulation of genes encoding several Phase I and Phase II metabolic enzymes, including several 3b-hydroxysteroid dehydrogenases (Hsd3b), cytochrome P450 (Cyp) enzymes, and sulfotransferases. In addition, our results indicate that RORa and RORg each affect the expression of a specific set of genes but also exhibit functional redundancy. Our study shows that RORa and RORg receptors influence the regulation of several metabolic pathways, including those involved in the metabolism of steroids, bile acids, and xenobiotics, suggesting that RORs are important in the control of metabolic homeostasis. RORa plays an important role in the regulation of energy homeostasis. Mice deficient in RORa are resistant to diet-induced obesity and reduced inflammation in adipose tissue. A number of lipogenic genes were identified that are positively regulated by RORa. Because RORs function as ligand-dependent transcription factors, RORa might be a therapeutic target for the management of obesity. RORg was found to play an important role in the circadian regulation of several genes downstream of the circadian clock. Our studies further demonstrated that Prox1 interacts with ROR nuclear receptors and represses the transcriptional activity of RORγ and expression of RORγ, thereby contributing to the down-regulation of several ROR target genes. The AF2 in the LBD of RORs and the homeo/propero-like domain of Prox1 are required for the interaction as well as repression. Our study identifies Prox1 as a novel modulator of ROR transcriptional regulation and as such is an integral part of the circadian clock and metabolic regulatory networks. II. TAK1: The nuclear orphan receptor TAK1 functions as a positive as well as a negative regulator of transcription; however little is know about factors mediating its activity. Yeast two-hybrid analysis using the ligand binding domain of TAK1 as bait identified a novel TAK1-interacting protein, referred to as TIP27. Our studies indicate that TIP27 is an effective repressor of transcriptional activation by TAK1 and, therefore, may play a critical role in the regulation of several physiological functions by TAK1. Generation of TAK1 knockout mice revealed several phenotypes that are currently being investigated. TAK1-deficient (TAK1-/-) mice and report that these mice exhibit a smaller cerebellum and deficit in foliation of lobules VI-VII. The absence of TAK1 results in a coordinated deficit in cerebellar granule neurons, Purkinje cells, and radial glia during development altering long-term neurobehavioral functioning. These data indicate that TAK1 is an important transcriptional modulator of neurodevelopmentally-regulated behavior. In addition, we found that TAK1 plays a role in the regulation of energy homeostasis. Mice deficient in TAK1 are protected against the development of obesity,hepatic steatosis,and insulin resistance. A number of lipogenic genes were identified that are positively regulated by TAK1. III. Receptor associated protein (RAP80), a nuclear protein containing two ubiquitin-interacting motifs (UIMs), interacts with the esstrogen receptor alpha (ERa) in an agonist dependent manner. In addition, RAP80 is implicated in DNA repair and is associated with the tumor suppressor Breast cancer-1 (BRCA1) protein complex and mediates BRCA1 translocation to sites of DNA damage. We showed that this translocation is dependent on the UIMs of RAP80. We demonstrated that the ataxia-telangiectasia mutated protein kinase (ATM) can phosphorylate RAP80 in vitro at Ser205. Using an anti-RAP80Ser205P antibody that specifically recognizes RAP80 phosphorylated at Ser205 we demonstrated that RAP80Ser205P translocates to sites of DNA damage. We show that this phosphorylation is mediated by ATM and does not require a functional BRCA1. Ultraviolet (UV) irradiation also induces translocation of RAP80 to DNA damage foci that co-localize with γ-H2AX. We further show that this translocation is also dependent on the UIMs of RAP80 and that the UV-induced phosphorylation of RAP80 at Ser205 is mediated by ATR, not ATM. Our findings suggest that RAP80 has a more general role in different types of DNA damage response signaling pathways. Using genomic and functional analysis we established that the expression of the RAP80 gene is regulated in a DNA damage-responsive manner by the master regulator p53. This regulation occurs at the transcriptional level through a noncanonical p53 response element in the RAP80 promoter. While it is inducible by p53, RAP80 is also able to regulate p53 through an association with both p53 and the E3 ubiquitin ligase HDM2, providing HDM2-dependent enhancement of p53 polyubiquitination. Thus, we provide evidence that RAP80 can function in an autoregulatory loop consisting of RAP80, HDM2 and the p53 master regulatory network, implying an important role for this loop in genome stability and oncogenesis. RAP80 knockout mice were generated to determine the effect of loss of RAP80 on DNA stability and susceptibility to cancer. . RAP80-/- mice were more susceptible to spontaneous lymphoma development and the development of DMBA-induced mammary gland tumors. Moreover, the loss of RAP80 accelerated tumor formation in both p53-/- and p53+/- mice. Our data indicate that RAP80-deficiency promotes genomic instability and causes an increase in cancer risk consistent with the concept that RAP80 exhibits a tumor suppressor function. III. Our studies further demonstrate that mice deficient in CD44 are considerably resistant to diet-induced hepatic steatosis, fibrogenesis, and inflammation, adipose-associated infiltration of M1 macrophages, glucose intolerance, and insulin resistance. These observations suggest that CD44 provides a critical link between metabolic changes and the development of inflammation and insulin resistance. Because CD44 functions as a receptor, it may provide a convenient therapeutic target in the management of lipid dysregulation in diet-induced liver disease and type 2 diabetes.

I. RORα 和γ：类维生素A 相关孤儿受体a 和g（RORa 和RORg）是核受体超家族的成员。为了确定 RORa 和 g 的生理功能，对 RORa 和 g 功能缺陷的小鼠进行了分析。 RORg 在免疫系统中表现出多种功能。 RORg 表达对于淋巴结器官发生是不可或缺的，并且在胸腺细胞稳态中发挥关键作用。 最近确定了 RORg 在 Th17 细胞分化中的作用。我们证明了 RORa 和 RORg 在 Th17 细胞分化过程中被诱导，并且双基因敲除小鼠对实验性自身免疫性脑脊髓炎（多发性硬化症模型）具有抵抗力。此外，RORg 缺陷小鼠对卵清蛋白 (OVA) 诱导的小鼠炎症不太敏感，小鼠是过敏性气道疾病的模型。 类维生素A相关孤儿受体α（RORa）和γ（RORg）均在肝脏中表达；然而，它们在该组织中的生理功能尚未明确定义。 RORa1 和 RORg1 在昼夜节律期间表现出振荡表达模式。通过微阵列分析比较 WT、RORa 缺陷交错小鼠 (RORasg/sg)、RORg-/- 和 RORasg/sgRORg-/- 双敲除 (DKO) 小鼠肝脏的基因表达谱，结果表明 RORa 和 RORg 在编码多种 I 期和 II 期代谢酶的基因调节中特别重要，包括几种 3b-羟基类固醇脱氢酶 (Hsd3b)、细胞色素 P450 (Cyp) 酶和磺基转移酶。此外，我们的结果表明，RORa 和 RORg 各自影响一组特定基因的表达，但也表现出功能冗余。我们的研究表明，RORa 和 RORg 受体影响多种代谢途径的调节，包括参与类固醇、胆汁酸和异生物质代谢的途径，表明 ROR 在代谢稳态的控制中很重要。 RORa 在能量稳态调节中发挥着重要作用。 RORa 缺陷的小鼠能够抵抗饮食引起的肥胖并减少脂肪组织的炎症。鉴定出许多脂肪生成基因受 RORa 正向调节。由于 ROR 作为配体依赖性转录因子发挥作用，因此 RORa 可能成为肥胖管理的治疗靶点。研究发现 RORg 在生物钟下游几个基因的昼夜节律调节中发挥着重要作用。 我们的研究进一步表明，Prox1 与 ROR 核受体相互作用，抑制 RORγ 的转录活性和 RORγ 的表达，从而导致多个 ROR 靶基因的下调。 ROR 的 LBD 中的 AF2 和 Prox1 的同源/原体样结构域是相互作用和抑制所必需的。我们的研究将 Prox1 确定为 ROR 转录调控的新型调节剂，因此是生物钟和代谢调控网络的组成部分。 二. TAK1：核孤儿受体 TAK1 充当转录的正调节因子和负调节因子；然而，人们对调节其活动的因素知之甚少。使用 TAK1 的配体结合域作为诱饵进行酵母双杂交分析，鉴定出一种新型 TAK1 相互作用蛋白，称为 TIP27。我们的研究表明，TIP27 是 TAK1 转录激活的有效抑制因子，因此可能在 TAK1 多种生理功能的调节中发挥关键作用。 TAK1 敲除小鼠的产生揭示了目前正在研究的几种表型。 TAK1 缺陷 (TAK1-/-) 小鼠并报告这些小鼠表现出较小的小脑和 VI-VII 小叶叶状结构缺陷。 TAK1 的缺失会导致发育过程中小脑颗粒神经元、浦肯野细胞和放射状胶质细胞的协调缺陷，从而改变长期神经行为功能。这些数据表明 TAK1 是神经发育调节行为的重要转录调节剂。此外，我们发现TAK1在能量稳态调节中发挥作用。缺乏 TAK1 的小鼠可以免受肥胖、肝脂肪变性和胰岛素抵抗的影响。鉴定出许多受 TAK1 正向调节的脂肪生成基因。 三．受体相关蛋白 (RAP80) 是一种含有两个泛素相互作用基序 (UIM) 的核蛋白，以激动剂依赖性方式与雌激素受体 α (ERa) 相互作用。此外，RAP80 参与 DNA 修复，并与肿瘤抑制乳腺癌 1 (BRCA1) 蛋白复合物相关，并介导 BRCA1 易位至 DNA 损伤位点。我们表明这种易位依赖于 RAP80 的 UIM。我们证明共济失调毛细血管扩张突变蛋白激酶 (ATM) 可以在体外磷酸化 RAP80 Ser205。使用特异性识别 Ser205 磷酸化 RAP80 的抗 RAP80Ser205P 抗体，我们证明 RAP80Ser205P 易位至 DNA 损伤位点。我们证明这种磷酸化是由 ATM 介导的，不需要功能性 BRCA1。紫外线 (UV) 照射还会诱导 RAP80 易位至与 γ-H2AX 共定位的 DNA 损伤灶。我们进一步表明，这种易位还依赖于 RAP80 的 UIM，并且 UV 诱导的 RAP80 Ser205 磷酸化是由 ATR 介导的，而不是 ATM。我们的研究结果表明 RAP80 在不同类型的 DNA 损伤反应信号通路中具有更普遍的作用。通过基因组和功能分析，我们确定 RAP80 基因的表达受到主调节器 p53 以 DNA 损伤响应方式的调节。这种调节通过 RAP80 启动子中的非规范 p53 响应元件发生在转录水平。 虽然它可由 p53 诱导，但 RAP80 还能够通过与 p53 和 E3 泛素连接酶 HDM2 的关联来调节 p53，从而提供 HDM2 依赖性的 p53 多泛素化增强。因此，我们提供的证据表明 RAP80 可以在由 RAP80、HDM2 和 p53 主调控网络组成的自动调节环中发挥作用，这意味着该环在基因组稳定性和肿瘤发生中发挥重要作用。培育 RAP80 敲除小鼠以确定 RAP80 缺失对 DNA 稳定性和癌症易感性的影响。 。 RAP80-/- 小鼠更容易发生自发性淋巴瘤和 DMBA 诱导的乳腺肿瘤。此外，RAP80 的缺失加速了 p53-/- 和 p53+/- 小鼠肿瘤的形成。我们的数据表明，RAP80 缺陷会促进基因组不稳定并导致癌症风险增加，这与 RAP80 表现出肿瘤抑制功能的概念一致。 三．我们的研究进一步表明，缺乏 CD44 的小鼠对饮食诱导的肝脂肪变性、纤维形成和炎症、脂肪相关的 M1 巨噬细胞浸润、葡萄糖不耐受和胰岛素抵抗有相当大的抵抗力。这些观察结果表明，CD44 在代谢变化与炎症和胰岛素抵抗的发展之间提供了关键的联系。由于 CD44 作为受体发挥作用，因此它可能为饮食诱发的肝病和 2 型糖尿病中脂质失调的治疗提供方便的治疗靶点。