THE ROLE OF INSULIN IN HUMAN FETAL LUNG DEVELOPMENT

描述：(改编自《调查者摘要》)：假设是 糖尿病妇女胎儿肺发育迟缓与 高胰岛素引起的表面活性物质相关蛋白缺乏症。目标 1阐明了胰岛素介导的信号转导途径 抑制SP-A、SP-B基因表达。信号转导抑制剂， 酶分析、信号中间产物的特性和转染法 具有主要的否定和构造活性的构造将被用于 验证PI-3K信号转导通路介导 胰岛素的作用。目标2是确定SP-A中的顺式作用元件 以及介导胰岛素抑制作用的SP-B基因。荧光素酶 报告基因构建将用于定位抑制的胰岛素反应 人SP-A1和SP-A2基因5‘侧翼区的元件。目标3是 鉴定与SP-A1和SP-B相互作用的转录因子 胰岛素反应元件。将使用电泳迁移率变化分析 验证HNF-3a和C/EBPA介导胰岛素诱导的假说 抑制SP-A、SP-B基因表达。目标4是描述分子 事件(磷酸化、定位和/或基因表达的变化) 将信号转导与转录因子联系起来，转录因子与 SP-A1和SP-B基因中的胰岛素反应元件。

DESCRIPTION: (Adapted from the Investigator's Abstract): The hypothesis is that delayed lung development in the fetus of the diabetic woman is related to surfactant-associated protein deficiency caused by high levels of insulin. Aim 1 is to elucidate the signal transduction pathways involved in insulin-mediated inhibition of SP-A and SP-B gene expression. Signal transduction inhibitors, enzyme assays, characterization of signaling intermediates and transfection with dominant negative and constitutively active constructs will be used to test the hypothesis that the PI-3K signal transduction pathway mediates the effects of insulin. Aim 2 is to identify the cis-acting elements in the SP-A and SP-B genes which mediate the inhibitory effects of insulin. Luciferase reporter gene constructs will be used to localize inhibitory insulin response elements in the 5' flanking region of the human SP-A1 and SP-A2 genes. Aim 3 is to identify the transcription factors that interact with the SP-A1 and SP-B insulin response elements. Electrophoretic mobility shift assays will be used to test the hypothesis that HNF-3a and C/EBPa mediate the insulin-induced inhibition of SP-A and SP-B gene expression. Aim 4 is to describe the molecular events (phosphorylation, localization, and/or changes in gene expression) that link signal transduction to transcription factors which interact with the insulin response elements in the SP-A1 and SP-B genes.