Lipid rafts, dopamine 1 receptor, and hypertension

脂筏、多巴胺 1 受体和高血压

• 批准号: 9886774
• 负责人: Pedro A. Jose
• 金额: $ 64.24万
• 依托单位: GEORGE WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-09 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9886774
• 关键词: ADRBK1 gene; Adenylate Cyclase; Agonist; Back; Biological; Blood Pressure; C57BL/6 Mouse; Caucasians; Cell membrane; Cells; Coupled; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; DRD1 Protein; DRD1 gene; Data; Diet; Dopamine; Dopamine D1 Receptor; Dopamine Receptor; Essential Hypertension; Ethnic Origin; Ethylmaleimide; Family; G protein coupled receptor kinase; G-Protein-Coupled Receptors; Gene Frequency; Genes; Genetic Polymorphism; Golgi Apparatus; Haplotypes; Human; Hypertension; Impairment; Kidney; Knowledge; Leucine; Lipids; Maintenance; Mediating; Membrane; Membrane Microdomains; Minor; Molecular; Mus; Mutate; Mutation; NADPH Oxidase; Palmitic Acylation Site; Paraoxonase-2; Pathway interactions; Pharmacology; Phosphorylation; Phosphotransferases; Plasma; Plasma Cells; Population; Production; Protein Dephosphorylation; Protein phosphatase; Proteins; Proximal Kidney Tubules; Reactive Oxygen Species; Receptor Gene; Recycling; Regulation; Renal tubule structure; Rodent; Scaffolding Protein; Sodium Chloride; Sorting - Cell Movement; Testing; Variant; Zinc Fingers; antioxidant enzyme; blood pressure regulation; desensitization; genetic variant; high salt diet; mutant; normotensive; palmitoylation; prevent; receptor; receptor expression; receptor function; response; salt sensitive hypertension; sorting nexins; trafficking

Project Summary The D1 dopamine receptor (D1R) is important in the regulation of blood pressure (BP). Drd1 germline deletion in mice causes hypertension. G protein-coupled receptor kinase type 4 (GRK4) is important in the normal cellular recycling and function of D1R. However, some of the recycled D1R has to be targeted to lipid rafts to be functional. Thus, mutant D1Rs 347C>A and 351C>A still target to the plasma membrane but fail to localize in lipid rafts; these mutations prevent the increase in D1R-mediated stimulation of cAMP production in renal proximal tubule cells (RPTCs) and impair (e.g., 347C>A) normal BP regulation in mice. C347 and C351 in D1R are palmitoylation sites; SNX19 functions as a scaffold protein for the palmitoylation of D1R at the Golgi, via Golgi-specific zinc finger protein. Lipid rafts are also needed for the proper membrane distribution and maintenance of adenylyl cyclases 5 and 6 and regulation by D1R. Inhibition or molecular biological disruption of palmitoylation prevents D1R targeting to lipid rafts, impairs D1R function, and causes hypertension. Silencing SNX19 impairs D1R-mediated increase in cAMP and decrease in Na+ transport in RPTCs but not distal convoluted tubule cells. Renal SNX19 is important in the regulation of BP; renal-restricted silencing of Snx19 increases BP in C57Bl/6 mice on normal but not low salt diet. Germline deletion of SNX19 in mice also increases BP on normal salt diet. SNX19 is upstream of D1R. SNX19 rs2298566 is associated with decreased ability to excrete Na+ and high BP in humans and impairs D1R function in human (h)RPTCs. SNX19 protein is decreased in hRPTCs from hypertensive humans. We will test the overall hypothesis that SNX19 is important in the trafficking of D1R to lipid rafts in the RPT plasma membrane for normal D1R function. Impaired functioning of D1R in the kidney, caused by its impaired trafficking to lipid rafts in RPT plasma membranes, causes salt-sensitive hypertension. Specific Aim 1 will test the hypothesis that SNX19 targeting of D1R into the lipid rafts of RPTC plasma membrane is crucial for normal D1R function. SNX19 and GRK4 interact in lipid rafts to regulate D1R function, including D1R-mediated inhibition of Na+ transport in RPTCs. Specific aim 2 will test the hypothesis that mutations of the palmitoylation sites in the D1R gene prevent the ability of SNX19 to target the D1R to lipid rafts in the RPTC plasma membrane. Germline deletion or renal-restricted deletion of SNX19 in C57Bl/6 mice causes salt- sensitive hypertension. Mutating DRD1 to prevent D1R targeting to lipid rafts of RPTC plasma membrane also causes salt-sensitive hypertension. These genes and their proteins could be targets in the treatment of human essential hypertension.

项目概要 D1 多巴胺受体 (D1R) 对于血压 (BP) 的调节很重要。博士1 小鼠种系缺失会导致高血压。 G 蛋白偶联受体激酶 4 型 (GRK4) 对于 D1R 的正常细胞回收和功能很重要。然而，一些 回收的 D1R 必须靶向脂筏才能发挥作用。因此，突变体 D1R 347C>A 和 351C>仍以质膜为目标，但未能定位于脂筏；这些突变 防止肾近曲小管中 D1R 介导的 cAMP 产生刺激增加 细胞（RPTC）并损害（例如，347C>A）小鼠的正常血压调节。 D1R 中的 C347 和 C351 是棕榈酰化位点； SNX19 作为 D1R 棕榈酰化的支架蛋白 高尔基体，通过高尔基体特异性锌指蛋白。适当的脂筏也是必要的 腺苷酸环化酶 5 和 6 的膜分布和维持以及 D1R 的调节。 棕榈酰化的抑制或分子生物学破坏可防止 D1R 靶向脂筏， 损害D1R功能，并导致高血压。沉默 SNX19 会损害 D1R 介导的 RPTC 中 cAMP 增加，Na+ 转运减少，但远曲小管细胞则不然。 肾 SNX19 在血压调节中发挥重要作用； Snx19 的肾限制性沉默增加 正常但非低盐饮食的 C57Bl/6 小鼠的血压。小鼠中 SNX19 的种系缺失 正常盐饮食会增加血压。 SNX19 是 D1R 的上游。 SNX19 rs2298566 关联 人类排泄 Na+ 的能力下降，血压升高，并损害人类 D1R 功能 (h) RPTC。高血压人群的 hRPTC 中 SNX19 蛋白减少。我们将测试 总体假设：SNX19 在 D1R 向 RPT 中脂筏的运输中发挥重要作用 质膜维持正常的 D1R 功能。 D1R 肾脏功能受损，导致 由于其向 RPT 质膜中脂筏的运输受损，导致盐敏感 高血压。具体目标 1 将检验 SNX19 将 D1R 靶向脂质的假设 RPTC 质膜筏对于 D1R 的正常功能至关重要。 SNX19 和 GRK4 相互作用 脂筏中调节 D1R 功能，包括 D1R 介导的 Na+ 转运抑制 RPTC。具体目标 2 将检验以下假设：棕榈酰化位点的突变 D1R 基因阻止 SNX19 将 D1R 靶向 RPTC 血浆中的脂筏的能力 膜。 C57Bl/6 小鼠中 SNX19 的种系缺失或肾限制性缺失会导致盐- 敏感高血压。突变 DRD1 以阻止 D1R 靶向 RPTC 血浆的脂筏 膜还会引起盐敏感性高血压。这些基因及其蛋白质可能是 治疗人类原发性高血压的目标。