Mesonephric Model of Podocyte Injury and Regeneration

摘要 这个K99/R00应用程序的目标是利用我为其开发的一个新的动物模型系统 肾病综合征与足细胞再生的分子机制研究。这将有助于 我的研究生涯向独立调查员职位的过渡。 肾病综合征(NS)是一种肾脏疾病，以蛋白尿、低蛋白血症、水肿和 高脂血症，由于肾小球滤过屏障(GFB)功能的破坏。超标的原因 75%的激素抵抗型肾病综合征(SRNS)病例仍不清楚，也没有有效的治疗方法 可用于治疗这种疾病，导致局灶性节段性肾小球硬化(FSGS)并导致 终末期肾病(ESKD)SRNS遗传病因的最新发现和啮齿动物的研究 足细胞损伤模型揭示了足细胞在GFB正常功能中的关键作用 肾病综合征的发病机制。然而，NS的啮齿动物模型不适合于高通量筛查 治疗这种疾病的药物。最近的研究已经确定了肾脏祖细胞的一个亚群 成年人类肾脏能够再生肾上皮细胞，包括足细胞，这表明 以干/祖细胞为基础的治疗肾病综合征的新方法。然而，人们对此知之甚少 关于足细胞的再生机制。 为了解决这些问题，我建议建立斑马鱼中肾作为一种新的模式系统 肾病综合征：(1)利用我所建立的转基因斑马鱼模型来筛选 改善蛋白尿的化学物质；(2)研究表达wt1b的肾祖细胞的潜能 斑马鱼足细胞再生及足细胞再生过程中的基因表达 已建立的用于筛选温度敏感型肾病斑马鱼突变株和 确定NS的新的遗传原因。拟议研究的完成将提供(1)新的 可导致NS治疗的化合物；(2)对足细胞机制的新见解 再生；(3)参与NS发病机制的新基因；(4)新的斑马鱼模型。 疾病。 作为儿科和传染病系的博士后研究员， 密歇根大学，我致力于将斑马鱼中肾细胞培养成一种新的动物模型系统 肾病综合症是我的直接职业目标。我的长期职业目标是让自己成为一名 肾脏研究领域的独立研究员，专注于肾脏疾病的动物模型。这个 该奖项的培训(K99)阶段将由Friedhelm Hildebrandt博士指导，他是 霍华德·休斯医学研究所和国际公认的人类遗传学领域的领导者 儿童肾脏疾病，包括肾病综合征。密歇根大学有几十个活跃的和 致力于肾脏发育、肾脏疾病和斑马鱼发育的合作研究小组 和遗传学，这为我的培训和职业发展提供了一个理想的环境。

ABSTRACT The objective of this K99/R00 application is to utilize a new animal model system that I have developed for the study of molecular mechanisms of nephrotic syndrome and podocyte regeneration. This will aid the transition of my research career toward an independent investigator position. Nephrotic syndrome (NS) is a kidney disease characterized by proteinuria, hypoalbuminemia, edema, and hyperlipidemia, due to the disruption of renal glomerular filtration barrier (GFB) function. The causes of over 75% of steroid resistant nephrotic syndrome (SRNS) cases are still unknown and no effective therapy is available for the disease, which results in focal segmental glomerular sclerosis (FSGS) and leads to end-stage kidney disease (ESKD). Recent discoveries of genetic causes of SRNS and studies of rodent models of podocyte damage revealed the pivotal role of podocytes in the normal function of GFB and the pathogenesis of NS. However, rodent models for NS are not suitable for high-throughput screening of therapeutical agents for the disease. Recent studies have identified a subset of renal progenitor cells in adult human kidney that are capable of regenerating renal epithelial cells, including podocytes, suggesting a novel stem/progenitor cell-based approach for the treatment of nephrotic syndrome. However, little is known about the regenerative mechanism of podocytes. To address these questions, I propose to establish zebrafish mesonephros as a new model system for nephrotic syndrome by: (1) utilizing the transgenic zebrafish models that I have generated to screen for chemicals ameliorating proteinuria; (2) investigating the potential of wt1b-expressing renal progenitor cell to regenerate podocytes in zebrafish and gene expression during podocyte regeneration; (3) using the established GFB assay(s) to screen for temperature-sensitive nephrotic zebrafish mutants and identify novel genetic causes of NS. Accomplishment of the proposed research will provide (1) new chemical compounds that can lead to therapies for NS; (2) new insights into the mechanism of podocyte regeneration; (3) new genes that are involved in the pathogenesis of NS; and (4) new zebrafish models for the disease. Being a postdoctoral research fellow in the Department of Pediatrics and Communicable Diseases, University of Michigan, I am committed to develop zebrafish mesonephros into a new animal model system for nephrotic syndrome as my immediate career goal. My long-term career goal is to establish myself as an independent investigator in the field of kidney research, focusing on animal models of kidney diseases. The training (K99) phase of this award will be mentored by Dr. Friedhelm Hildebrandt, who is an investigator of Howard Hughes Medical Institute and internationally recognized leader in the fields of human genetics of pediatric kidney diseases, including nephrotic syndrome. University of Michigan has dozens of active and collaborative research groups working on kidney development, kidney diseases, and zebrafish development and genetics, which provides an ideal environment for my training and career development.