A NOVEL TRANSGENIC MOUSE MODEL FOR DIABETES

一种新型糖尿病转基因小鼠模型

• 批准号: 6898106
• 负责人: AMY S LEE
• 金额: $ 16.25万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-05-01 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6898106
• 关键词: diabetes mellitus genetics; disease /disorder model; genetic models; genetically modified animals; glucose metabolism; laboratory mouse; model design /development; noninsulin dependent diabetes mellitus; obesity

DESCRIPTION (provided by applicant): This proposal aims to establish a novel transgenic mouse line, referred to as D2D that can serve as a model for the study of diabetes and obesity. Our laboratory has been studying the transcriptional regulation of a glucose regulated protein GRP78 that is a major molecular chaperone localized in the endoplasmic reticulum (ER). To understand how physiological stress activates the Grp78 promoter in vivo, we have created a series of transgenic mouse lines. One of these lines, D2D, contains a genetically modified version of the Grp78 promoter driving the expression of the bacterial lacZ gene encoding for beta-galactosidase. In this line, the lacZ transgene activity is strongly expressed in all pancreatic beta-cells, and some expression is also detected in the liver and brain including the hypothalamus controlling glucose sensing. To our surprise, we discovered that the D2D founder mouse became increasingly obese with age. Further analysis of the founder and its F1 and F2 offspring reveals that the D2D line exhibits properties of type II diabetes and age dependent onset of obesity. Examination of the D2D pancreatic sections showed normal range of beta-cell mass, proliferation and apoptosis. Taken together, our preliminary results suggest that D2D could offer a novel model for type II diabetes and obesity, and provide a new experimental system for the study of beta-cell defect with possible connection to liver and brain problems. In Specific Aim 1, we propose to perform comprehensive analyses of glucose metabolism and phenotypic tests for the D2D mice and two other independently derived lines that exhibit similar but distinct lacZ expression profile. In Specific Aim 2, we will determine the various mechanism(s) that could account for the diabetic phenotype observed in D2D. This pilot project has the potential to identify a new gene critical for glucose homeostasis through integration site analysis of D2D and it will provide the foundation for future studies to decipher the detail mechanism and preclinical applications of the D2D model towards therapy of diabetes and obesity.

描述（由申请人提供）：本提案旨在建立一种新的转基因小鼠系，称为D2D，可作为糖尿病和肥胖研究的模型。我们的实验室一直在研究葡萄糖调节蛋白GRP78的转录调控，GRP78是内质网（ER）中主要的分子伴侣。为了了解生理应激如何在体内激活Grp78启动子，我们创建了一系列转基因小鼠系。其中一个品系D2D含有Grp78启动子的转基因版本，该启动子驱动编码β -半乳糖苷酶的细菌lacZ基因的表达。在这条线中，lacZ转基因活性在所有胰腺β细胞中都有强烈表达，在肝脏和大脑中也检测到一些表达，包括控制葡萄糖传感的下丘脑。令我们惊讶的是，我们发现D2D创始小鼠随着年龄的增长变得越来越肥胖。对创始人及其F1和F2后代的进一步分析表明，D2D系表现出II型糖尿病和年龄依赖性肥胖发病的特性。胰腺D2D切片显示β细胞团块、增殖和凋亡范围正常。综上所述，我们的初步结果表明，D2D可以为II型糖尿病和肥胖提供一个新的模型，并为研究可能与肝和脑问题相关的β细胞缺陷提供一个新的实验系统。在具体目标1中，我们建议对D2D小鼠和其他两个独立衍生的小鼠进行糖代谢和表型测试的综合分析，这些小鼠表现出相似但不同的lacZ表达谱。在特异性目标2中，我们将确定各种机制，可以解释在D2D中观察到的糖尿病表型。该试点项目有可能通过D2D的整合位点分析鉴定出葡萄糖稳态的新关键基因，并将为未来的研究提供基础，以破译D2D模型治疗糖尿病和肥胖的详细机制和临床前应用。