Linking endocytosis to cell signaling in proteinuria induced tubular apoptosis

将内吞作用与蛋白尿诱导的肾小管凋亡中的细胞信号传导联系起来

• 批准号: 7845027
• 负责人: Elif Erkan
• 金额: $ 13.92万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-05-15 至 2012-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7845027
• 关键词: Accounting; Adaptor Signaling Protein; Adolescent; Adult; Affect; Albumins; Apoptosis; Apoptotic; Arts; Atrophic; Binding; Biological Assay; Biotinylation; Cell Proliferation; Cell Survival; Cell model; Cells; Cellular biology; Cessation of life; Chronic Glomerulonephritis; Chronic Kidney Failure; Clathrin; Clinical; Cloning; Deterioration; Disease; Down-Regulation; End stage renal failure; Endocytosis; Epithelial Cells; Event; Fibrosis; Goals; Human; Image; Impairment; In Vitro; Inflammatory; Injury; Kidney; Kidney Diseases; Knock-in Mouse; LDL-Receptor Related Protein 2; Lead; Learning; Ligand Binding; Link; Mediating; Mediator of activation protein; Medical; Mentors; Methods; Mitochondria; Modeling; Molecular; Monitor; Morbidity - disease rate; Nature; Nutrient; Outcome Measure; Pathologic; Pathway interactions; Patients; Phosphorylation; Physiologic pulse; Physiological; Plasma Proteins; Play; Prevention strategy; Principal Investigator; Process; Production; Prognostic Factor; Proteins; Proteinuria; Proto-Oncogene Proteins c-akt; Renal function; Renal glomerular disease; Role; Series; Signal Transduction; Site; Sorting - Cell Movement; Techniques; Testing; Therapeutic Intervention; Training; Tubular formation; cell injury; glomerular filtration; in vivo Model; knock-down; mortality; novel; prevent; protein complex; protein protein interaction; public health relevance; receptor; receptor mediated endocytosis; research study; response; tool; trafficking; uptake; yeast two hybrid system

DESCRIPTION (provided by applicant): Chronic glomerulonephritis is associated with progressive kidney disease in adults and adolescents. In glomerular disorders, high amounts of protein particularly albumin pass through the damaged glomerular filtration barrier. It has long been established that proteinuria is detrimental to kidneys and patients with heavy proteinuria show a rapid deterioration of their renal function. In the previous studies, the candidate showed that high concentrations of albumin, above the reabsorptive capacity of the proximal tubule cells, mimicking the nephrotic milieu result in apoptosis. Endocytosis of proteins and nutrients in the proximal tubule is regulated by a highly sophisticated machinery containing clathrin, receptors and adaptor proteins. The best described receptor-adaptor protein complex in the proximal tubule is megalin-disabled-2 (Dab2). Dab2 is also implicated in signal transduction events regulating cell proliferation and differentiation. The candidate proposes that there is an overlap between endocytosis and cell signaling event that mediate albumin induced apoptosis. Preliminary studies showed an interaction between the survival factor protein kinase B (PKB/Akt) and endocytic adaptor protein Dab2. The down regulation of this interaction associated with albumin-induced apoptosis allowed us to hypothesize that Dab2 is a key adaptor protein that regulates both apoptosis and endocytosis. The goal of this project is to elucidate the mechanism and implications of this interaction to cell survival. Thus in aim 1, the candidate will investigate the role of albumin endocytosis on Dab2-PKB interaction and the fate/trafficking of megalin/Dab2 with albumin overload. In aim 2, the candidate will study the role of Dab2 in albumin-induced apoptosis and the nature of Dab2-PKB interaction. Short-term goal of the candidate is to acquire further training that will enable her to learn the state-of-art cell biology techniques such as cloning, protein-protein interactions and confocal imaging under the guidance of her mentor Dr.Linton Traub. The long term objective is to discover therapeutic interventions that will halt the proteinuria induced progression of glomerular disease by investigating the molecular network of events that are associated with proximal tubule injury and albumin endocytosis. PUBLIC HEALTH RELEVANCE: Chronic glomerulonephritis is an important problem with high morbidity resulting in chronic renal failure. The degree of proteinuria correlates with the rate of progression. The main goal of this project is to dissect the mechanism of proteinuria induced kidney damage in an attempt to develop preventive strategies to halt progression of glomerular diseases.

描述(由申请人提供)： 慢性肾小球肾炎与成人和青少年的进行性肾脏疾病有关。在肾小球疾病中，大量的蛋白质，特别是白蛋白通过受损的肾小球滤过屏障。蛋白尿对肾脏的损害由来已久，蛋白尿严重的患者表现出肾功能的迅速恶化。在以前的研究中，候选研究表明，高浓度的白蛋白高于近端小管细胞的重吸收能力，模拟肾病环境会导致细胞凋亡。近端小管中蛋白质和营养物质的内吞作用是由一个高度复杂的机制调节的，该机制含有网状蛋白、受体和接头蛋白。在近端小管中描述最好的受体-适配器蛋白复合体是巨蛋白失活-2(DAB2)。DAB2还参与调节细胞增殖和分化的信号转导事件。这位候选人提出，内吞作用和介导白蛋白诱导的细胞凋亡的细胞信号事件之间存在重叠。初步研究表明，存活因子蛋白激酶B(PKB/Akt)与内吞适配蛋白DAB2之间存在相互作用。这种与白蛋白诱导的细胞凋亡相关的相互作用的下调使我们可以假设DAB2是一种关键的适配器蛋白，既调节细胞凋亡又调节细胞吞噬。这个项目的目标是阐明这种相互作用对细胞生存的机制和影响。因此，在目标1中，候选人将研究白蛋白内吞作用在DAB2-PKB相互作用中的作用以及白蛋白超载时megalin/DAB2的命运/转运。在目标2中，候选人将研究DAB2在白蛋白诱导的细胞凋亡中的作用以及DAB2-PKB相互作用的性质。应聘者的短期目标是获得进一步的培训，使她能够在她的导师林顿·特劳布博士的指导下学习最先进的细胞生物学技术，如克隆、蛋白质相互作用和共聚焦成像。长期目标是通过研究与近端小管损伤和白蛋白内吞相关的事件的分子网络，发现可以阻止蛋白尿引起的肾小球疾病进展的治疗干预措施。 公共卫生相关性：慢性肾小球肾炎是一个发病率很高的重要问题，可导致慢性肾功能衰竭。蛋白尿的程度与进展速度有关。该项目的主要目标是剖析蛋白尿引起的肾脏损害的机制，试图开发预防策略来阻止肾小球疾病的进展。