LAMININ BETA2 AND GLOMERULAR FILTRATION

层粘连蛋白 Beta2 和肾小球滤过

基本信息

批准号：
7571679
负责人：
JEFFREY H MINER
金额：
$ 32.3万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-03-01 至 2012-02-29
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7571679
关键词：
Address Affect Agrin Albumins Amino Acids Applications Grants Architecture Basement membrane Behavior Biochemical Biological Assay Biology Cell Membrane Permeability Cells Collagen Type IV Companions Congenital Nephrotic Syndrome Congenital neurologic anomalies Coupled Data Defect Diabetic Nephropathy Diffuse Diffusion Disease Disease Progression Down-Regulation Endothelial Cells Engineering Etiology Exhibits Extracellular Matrix Extracellular Space Failure Ferritin Filtration Foot Process Gel Genetic Goals Grant Half-Life Health Heparan Sulfate Proteoglycan Heterogeneity Human Human Engineering In Vitro Incidence Kidney Kidney Diseases Kinetics Laboratories Laminin Lead Life Maintenance Membrane Biology Methods Missense Mutation Mus Mutation Nature Nephrotic Syndrome Nervous system structure Neuromuscular Junction Nidogen Obesity Plasma Proteins Play Point Mutation Porosity Proteins Proteinuria Proteomics Publishing Renal glomerular disease Role Signal Transduction Specificity Synapses Syndrome Testing Transgenic Mice Translating abstracting design disease-causing mutation glomerular basement membrane glomerular filtration human disease in vivo insight interest laminin S laminin-1 membrane assembly mutant null mutation overexpression podocyte polymerization prevent programs slit diaphragm stem

项目摘要

DESCRIPTION (provided by applicant): Project Summary/Abstract Kidney disease is huge worldwide health problem that is becoming increasingly prevalent. Primary glomerular disease, both acquired and genetic, represents a significant proportion of these cases, due in part to the incidence of diabetic nephropathy. We are interested in understanding the makeup of the glomerular filtration barrier and how it becomes damaged and leaky to plasma proteins. Our focus over the last decade has been to investigate the composition and function of the glomerular basement membrane (GBM), a specialized extracellular matrix that is an integral component of the filtration barrier. The GBM contains laminin, collagen IV, nidogen, and the heparan sulfate proteoglycan agrin. Recent analysis of mice lacking the laminin 22 chain, the only laminin 2 chain present in normal GBM, suggests that the GBM itself serves as the primary barrier to albumin, as the affected mice exhibit proteinuria even when podocytes have apparently normal foot process and slit diaphragm architecture. In addition, in vivo GBM permeability studies show that the mutant GBM is more permeable to ferritin than is control. Recently, mutations in human LAMB2 have been shown to cause kidney disease. Null mutations cause Pierson syndrome (congenital nephrotic syndrome with ocular and nervous system abnormalities), whereas some missense mutations cause isolated congenital nephrotic syndrome. The focus of this proposal is to understand the mechanism whereby these mutations in human LAMB2 cause glomerular filtration defects. To accomplish this, we will 1) engineer human LAMB2 missense mutations into mice so that behavior of the mutant proteins, disease progression, and glomerular ultrastructure can be followed in detail; 2) use biochemical methods to investigate the ability of the mutant forms to assemble and polymerize in vitro; 3) test the hypothesis that a reduction in the amount of total laminin in the GBM in the absence of 22 contributes to filtration barrier defects; 4) assay the ability of laminin heterotrimers and agrin to diffuse in the plane of the GBM; 5) determine the half-lives of laminin 22 and agrin in the GBM. Together, the results of these studies will provide important new insights into laminin and basement membrane biology and lead to a better understanding of the mechanism of glomerular filtration and the etiology of glomerular disease. Project Narrative/Relevance Kidney disease is huge worldwide health problem that is becoming increasingly prevalent. Primary glomerular disease represents a significant proportion of these cases, due in part to the increasing incidence of diabetic nephropathy and obesity. The goal of this proposal is to provide a better understanding the makeup of the glomerular filtration barrier and how it becomes damaged and leaky to plasma proteins, with a focus on laminin 22, an important component of the glomerular basement membrane.

描述（由申请人提供）：项目摘要/摘要肾脏疾病是越来越普遍的全球健康问题。原发性肾小球疾病均获得遗传和遗传性，代表着这些病例的很大一部分，部分原因是糖尿病性肾病的发生率。我们有兴趣了解肾小球滤过屏障的构成，以及它如何损坏和对等离子体蛋白的漏水。在过去的十年中，我们的重点是研究肾小球基底膜（GBM）的组成和功能，这是一种专门的细胞外基质，是过滤屏障的组成部分。 GBM含有层粘连蛋白，胶原蛋白IV，Nidogen和硫酸乙酰肝素蛋白聚糖Agrin。对缺乏层粘连蛋白22链的小鼠（正常GBM中唯一存在的层粘连蛋白2链）的最新分析表明，GBM本身是白蛋白的主要障碍，因为受影响的小鼠即使在足够的脚步过程中显然具有正常的脚步过程和裂解膜片结构，也会表现出蛋白尿。此外，体内GBM渗透率研究表明，突变体GBM对铁蛋白的渗透性比对照更容易渗透。最近，人LAMB2中的突变已显示出引起肾脏疾病。无效突变引起皮尔森综合征（先天性肾病综合征，眼和神经系统异常），而某些错义突变会导致孤立的先天性肾病综合征。该提案的重点是了解人LAMB2中这些突变会导致肾小球过滤缺陷的机制。为此，我们将1）工程师人类LAMB2错义突变到小鼠中，以便可以详细遵循突变蛋白，疾病进展和肾小球超微结构的行为； 2）使用生化方法研究突变体在体外组装和聚合的能力； 3）检验以下假设：在不存在22个GBM中，GBM中总层粘连蛋白的量减少有助于过滤屏障缺陷； 4）测定层粘连蛋白异三聚体和Agrin在GBM平面中扩散的能力； 5）确定GBM中层粘连蛋白22和Agrin的半衰期。总之，这些研究的结果将为层粘连蛋白和基底膜生物学提供重要的新见解，并可以更好地理解肾小球过滤的机理和肾小球疾病的病因。项目叙述/相关性肾脏疾病是越来越普遍的全球健康问题。原发性肾小球疾病代表着这些病例的很大一部分，部分原因是糖尿病性肾病和肥胖的发生率增加。该提案的目的是更好地了解肾小球滤过屏障的构成，以及它如何损坏和渗漏到血浆蛋白，重点是层粘连蛋白22，这是肾小球基底膜的重要组成部分。