Determination of IGFBP-3 and -4 mRNA Downregulation by HB-EGF

HB-EGF 下调 IGFBP-3 和 -4 mRNA 的测定

基本信息

批准号：
7252381
负责人：
PAUL A HARDING
金额：
$ 21.09万
依托单位：
MIAMI UNIVERSITY OXFORD
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-05-10 至 2011-05-09
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7252381
关键词：
Affect Aliquot Animals Binding Binding Proteins Biological Cell Line Cell Proliferation Complementary DNA Condition Conditioned Culture Media Data Diabetes Mellitus Diabetic mouse Disruption Disulfides Down-Regulation EGF gene EGF-Like Domain Epidermal Growth Factor Receptor Goals Growth Growth Factor Hypertrophy Immunohistochemistry Individual Insulin Insulin-Like Growth Factor Binding Protein 3 Insulin-Like Growth Factor I Insulin-Like Growth-Factor Binding Protein 1 Insulin-Like Growth-Factor-Binding Proteins Kidney Kidney Diseases Knockout Mice Laboratories Length Ligands Light Measures Mediating Mediator of activation protein Membrane Messenger RNA Mus Process Protein Overexpression Proteins Proteolytic Processing Puberty RNA Radioimmunoassay Rattus Resistance Reverse Transcriptase Polymerase Chain Reaction Role Serum Signal Pathway Signal Transduction Site Somatomedins Streptozocin Sum Time Transgenic Mice Transgenic Organisms Tyrosine Phosphorylation Western Blotting analog diabetic disulfide bond extracellular factor C heparin-binding EGF-like growth factor insight kidney cell mouse model non-diabetic research study response stable cell line

项目摘要

DESCRIPTION (provided by applicant): The primary goal of our laboratory is to understand the role of growth factors in diabetes. We will investigate the mechanisms of heparin-binding EGF-like growth factor (HBEGF) in the insulin-like signaling pathway. HB-EGF stimulates cell proliferation and is up-regulated in response to diabetic conditions (Lee et al., 1995). In order to investigate the role of HB-EGF in diabetes, we will induce diabetes in both HB-EGF transgenic mouse mice that over-expresses HB-EGF in the kidney (Provenzano et al., 2005) and an HB-EGF null mouse model (Jackson et al., 2003) which lack HB-EGF. The kidneys will be analyzed for renal hypertrophy, an early indicator of diabetes, prior to the onset of puberty and immediately after puberty. Furthermore, a second growth factor, insulin-like growth factor (IGF-I), an important mediator of growth, accumulates in the kidney under diabetic conditions. Serum and kidney IGF-I levels will be measured in diabetic and nondiabetic animals. IGF-I levels are in part regulated by insulin-like binding proteins (IGFBPs). We have previously demonstrated that HB-EGF transgenic mice downregulate IGFBP-3 and -4 specifically in the kidney. In light of these data, we will quantify IGFBP-1 -5 in the kidney of diabetic and nondiabetic HB-EGF transgenic and HB-EGF null mice to determine the effects of these IGFBPs on diabetes by HB-EGF. HB-EGF is a single membrane spanning protein that undergoes extensive proteolytic processing the results in both extracellular and intracellular domains that are each capable of stimulating cellular division. We will determine whether one or both of these domains are responsible for mediating the insulin-like effects or whether the insulin-like effects are solely mediated by proteolytic processing. To gain insight into the HB-EGF structural requirements for insulin-like signaling, we will individually disrupt each of the 3 disulfide bonds within the EGF-like domain to determine which of these disulfide bonds are necessary to elicit biological activity. In sum, this proposal outlines experiments that will determine the emerging role of HB-EGF in renal disease as a result of diabetes.

描述（由申请人提供）：我们实验室的主要目标是了解生长因子在糖尿病中的作用。我们将研究肝素结合EGF样生长因子（HBEGF）在胰岛素样信号通路中的机制。 HB-EGF 刺激细胞增殖，并在糖尿病情况下上调（Lee 等，1995）。为了研究 HB-EGF 在糖尿病中的作用，我们将在肾脏中过度表达 HB-EGF 的 HB-EGF 转基因小鼠（Provenzano 等，2005）和 HB-EGF 缺失小鼠中诱导糖尿病。模型（Jackson 等，2003）缺乏 HB-EGF。在青春期开始前和青春期后立即对肾脏进行肾肥大分析，肾肥大是糖尿病的早期指标。此外，第二种生长因子，胰岛素样生长因子（IGF-I），一种重要的生长介质，在糖尿病条件下在肾脏中积聚。将测量糖尿病和非糖尿病动物的血清和肾脏 IGF-I 水平。 IGF-I 水平部分受胰岛素样结合蛋白 (IGFBP) 调节。我们之前已经证明 HB-EGF 转基因小鼠特别在肾脏中下调 IGFBP-3 和 -4。根据这些数据，我们将量化糖尿病和非糖尿病 HB-EGF 转基因小鼠和 HB-EGF 缺失小鼠肾脏中的 IGFBP-1 -5，以确定这些 IGFBP 通过 HB-EGF 对糖尿病的影响。 HB-EGF 是一种单跨膜蛋白，经过广泛的蛋白水解加工，产生细胞外和细胞内结构域，每个结构域都能够刺激细胞分裂。我们将确定这些结构域中的一个或两个是否负责介导胰岛素样作用，或者胰岛素样作用是否仅由蛋白水解加工介导。为了深入了解 HB-EGF 对胰岛素样信号传导的结构要求，我们将单独破坏 EGF 样结构域内的 3 个二硫键，以确定这些二硫键中的哪一个键对于引发生物活性是必要的。总之，该提案概述了一些实验，这些实验将确定 HB-EGF 在糖尿病引起的肾脏疾病中的新作用。