Role of the COP9 Signalosome (CSN) in kidney disease and hypertension

COP9 信号体 (CSN) 在肾脏疾病和高血压中的作用

• 批准号: 10359736
• 负责人: Ryan J Cornelius
• 金额: $ 12.97万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-02 至 2025-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10359736
• 关键词: American; Area; Award; Binding; Blood Pressure; COPS5 gene; Catalytic Domain; Cells; Chronic Kidney Failure; Complex; Cullin Proteins; Cultured Cells; DNA Sequence Alteration; Data; Development; Disease; Distal; Distal convoluted renal tubule structure; Environment; Excision; Experimental Designs; Failure; Familial disease; Functional disorder; Future; Genetic; Goals; Heart Diseases; Homeostasis; Human; Hypertension; Impairment; In Vitro; Journals; Kidney; Kidney Diseases; Kidney Failure; Knockout Mice; Lead; Ligase; Lysine; Mediating; Medical; Mendelian disorder; Mentors; Modeling; Molecular; Mus; Mutation; Nephrons; Pathogenesis; Pathway interactions; Pharmacologic Substance; Phenotype; Phosphotransferases; Physiological; Physiology; Play; Positioning Attribute; Potassium; Prevention; Protein Subunits; Proteins; Public Health; Publishing; Regulation; Renal tubule structure; Research; Research Personnel; Risk Factors; Role; Site; Societies; Sodium Chloride; Stroke; Syndrome; Techniques; Testing; Type II Pseudohypoaldosteronism; Ubiquitin; Ubiquitin Like Proteins; Up-Regulation; Work; blood pressure regulation; cost efficient; cullin-3; disease phenotype; familial hyperkalemic hypertension; human disease; hypertension treatment; in vivo; in vivo evaluation; interest; kidney fibrosis; mouse model; multicatalytic endopeptidase complex; mutant; novel therapeutics; prevent; protein degradation; renal damage; skills; success; symporter; thiazide; ubiquitin ligase; ubiquitin-protein ligase

Project Summary / Abstract Hypertension is the most common risk factor for heart disease and stroke; therefore, it is important to understand the pathogenesis of hypertension for better prevention and treatment. Rare Mendelian causes of hypertension identify previously unrecognized physiological pathways and networks, which can illuminate new treatments for disease. The Mendelian syndrome Familial Hyperkalemic Hypertension (FHHt, or pseudohypoaldosteronism type II) is a monogenic disease resulting from mutations which increase expression of with-no-lysine kinases (WNKs). Cullin-RING ligases (CRLs) were recently discovered to regulate blood pressure via proteasomal degradation of WNKs. Regulation of CRL activity is facilitated by the deneddylase, COP9 Signalosome (CSN), which binds to the complex and removes the ubiquitin-like protein, NEDD8. A mutation in cullin 3 (CUL3) causes FHHt and was shown, by in vitro analysis, to have enhanced CUL3 neddylation, increased degradation of the substrate adaptor kelch-like 3 (KLHL3), and decreased binding to the CSN. We hypothesized that the impaired interaction with the CSN was integral to the disease. The CSN is a well-studied multi-subunit protein, but the data here provides the first evidence that disordered CSN activity in the kidney may relate to hypertension and chronic kidney disease (CKD). The applicant has characterized a genetic mouse model of CSN dysfunction, in which the catalytic subunit of the CSN, Jab1 is deleted from kidney-tubule cells (KS-Jab1-/-). These mice developed an unusual phenotype; there was decreased KLHL3 and upregulation of the WNK-SPAK pathway akin to FHHt, however, several unexpected consequences of Jab1 deletion throughout the nephron were noted that made the observed phenotype differ from the human disease. This included a decrease in the abundance of the Na-Cl co-transporter (NCC) after several weeks, and progressive and spontaneous kidney fibrosis, mimicking chronic kidney disease. Here, the applicant proposes to further explore these provocative results in three specific aims. Aim 1 will continue to test the hypothesis that impaired CSN function causes FHHt by generating mouse models that more faithfully mimic the disease mutation. In Aim 2, a combination of in vitro and in vivo techniques will be used to determine whether the CSN plays a role in modulating NCC directly. Aim 3 will examine the kidney damage caused by deletion of Jab1. Nrf2 accumulation will be investigated as a possible mechanism for the damage by generating Jab1 and Nrf2 double knockout mice. In addition to successful completion of these aims the mentoring and scientific environment make the applicant an ideal candidate to develop independence in renal physiology research. The proposed research will help reveal the mechanisms involved in regulation of blood pressure through the CUL3-KLHL3-WNK4 pathway which could lead to pharmaceutical treatment of hypertension by targeting CRLs, or the CSN. The results will also open two entirely new areas of focus, the role that the CSN plays in regulating NCC degradation and the potential role played by the CSN in mediating or accelerating the development of chronic kidney disease.

项目总结/摘要 高血压是心脏病和中风最常见的危险因素;因此，重要的是要了解 对高血压的发病机理进行更好的防治。罕见的孟德尔式高血压病因 识别以前未被识别的生理途径和网络，这可以阐明新的治疗方法， 疾病孟德尔综合征家族性高钾血症（FHHt，或假性醛固酮减少症 II型）是由增加无赖氨酸激酶表达的突变引起的单基因疾病 （WNKs）。最近发现Cullin-RING连接酶（CRL）通过蛋白酶体调节血压。 WNK的降解。CRL活性的调节由去卷曲酶，COP 9信号体（CSN）， 它与复合物结合并去除泛素样蛋白NEDD 8。cullin 3（CUL 3）的突变导致 通过体外分析显示，FHHt和FHHt具有增强的CUL 3 neddylation， 底物衔接子kelch样3（KLHL 3），并减少与CSN的结合。我们假设受损的人 与CSN的相互作用是疾病的组成部分。CSN是一种被充分研究的多亚基蛋白，但是 这里的数据提供了第一个证据，表明肾脏中CSN活性紊乱可能与高血压有关， 慢性肾病（CKD）。申请人已经表征了CSN功能障碍的遗传小鼠模型， 其中CSN的催化亚基Jab 1从肾小管细胞中缺失（KS-Jab 1-/-）。这些小鼠 出现了一种不寻常的表型; KLHL 3减少，WNK-SPAK通路上调 然而，与FHHt类似，注意到Jab 1在整个肾单位中缺失的几个意想不到的后果 使得观察到的表型不同于人类疾病。这包括了 几周后的Na-Cl协同转运蛋白（NCC），以及进行性和自发性肾纤维化， 模仿慢性肾病在此，申请人建议进一步探索这些具有启发性的结果， 三个具体目标。目标1将继续检验CSN功能受损导致FHHt的假设， 产生更忠实地模仿疾病突变的小鼠模型。在目标2中，体外和体外细胞培养的组合， 将使用体内技术来确定CSN是否在直接调节NCC中起作用。目标3将 检查Jab 1缺失引起的肾损伤。Nrf 2蓄积将作为可能的研究 通过产生Jab 1和Nrf 2双敲除小鼠来研究损伤机制。除了成功 完成这些目标的指导和科学环境使申请人成为理想的候选人， 在肾脏生理学研究方面发展独立性。这项拟议中的研究将有助于揭示 通过CUL 3-KLHL 3-WNK 4通路参与血压调节，这可能导致 通过靶向CRL或CSN的高血压药物治疗。结果也将完全打开两个 新的重点领域，CSN在调节NCC退化方面发挥的作用，以及CSN CSN介导或加速慢性肾脏疾病的发展。