CGMP-Dependent Protein Kinase (PKG) Expression

CGMP 依赖性蛋白激酶 (PKG) 表达

基本信息

批准号：
7268376
负责人：
Thomas M. Lincoln
金额：
$ 32.96万
依托单位：
UNIVERSITY OF SOUTH ALABAMA
依托单位国家：
美国
项目类别：
财政年份：
2001
资助国家：
美国
起止时间：
2001-01-01 至 2011-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7268376
关键词：
26S proteasome 3&apos Untranslated Regions Accounting Adopted Antiatherogenic Atherosclerosis Binding Binding Proteins Blood Vessels Cell physiology Cells Characteristics Condition Contractile Proteins Cyclic GMP Cyclic GMP-Dependent Protein Kinases Disruption Down-Regulation Elevation Enzymes Funding Gene Expression Genes Growth Growth Factor Human In Vitro Inflammation Inflammatory Interleukin-1 Laboratories Literature Mediating Messenger RNA Molecular Muscle relaxation phase Nature Nitric Oxide Not Defined Personal Satisfaction Phenotype Phosphotransferases Play Polyadenylation Process Production Promoter Regions Property Protein Binding Protein Isoforms Protein Kinase Protein Region Proteins Proteolysis Reader Regulation Role Science Signal Transduction Site Smooth Muscle Myocytes Surface Testing Tumor Necrosis Factor-alpha Ubiquitin Ubiquitination Vasodilation cGMP-dependent protein kinase I cell growth cis acting element cyclic GMP-binding protein cytokine design human NOS2A protein in vivo mRNA Stability multicatalytic endopeptidase complex protein expression response ubiquitin-protein ligase

项目摘要

DESCRIPTION (provided by applicant): Type-l cyclic GMP-dependent protein kinase (PKG-I) mediates nitric oxide (NO) signaling in vascular smooth muscle cells (VSMC). Two isoforms, PKG-la and PKG-I¿, are believed to mediate the NO-dependent smooth muscle relaxation, inhibition of cell growth, and increase in contractile protein gene expression. However, inflammatory cytokines such as interleukin-1 (IL-1) are known to stimulate VSMC growth and block contractile protein gene expression. Our laboratory has shown that inflammatory cytokines also inhibit PKG-I expression in VSMC suggesting that at least one mechanism of action of these cytokines is to suppress PKG-I and induce a fibroproliferative VSMC phenotype. The mechanisms by which cytokines inhibit VSMC expression of PKG-I will be explored in this proposal. This is a basic and fundamental science proposal to identify in VSMC the molecular mechanisms regulating PKG-I expression in these cells. The central hypothesis is that IL-1 and other cytokines down-regulate PKG-I expression through two major mechanisms: first, through increased production of cGMP in the cells (via and induction of type II NO synthase or iNOS), PKG-I is ubiquitinylated and degraded in the 26S proteasome, and second, through suppression of AU-rich binding proteins that bind to and stabilize the PKG-I mRNA. Aim 1 will examine the mechanisms by which PKG-I is targeted for ubiquitinylation. Our hypothesis is that the binding of cGMP, specifically to the PKG-la isoform, induces autophosphorylation of the regulatory domain of the kinase which targets it for ubiquitinylation. We will identify the autophosphorylation site, the ubiquitinylation site, and the E3 ligase that binds autophosphorylated PKG-la. The effects of down-regulation of PKG-la on VSMC phenotypic properties will be assessed. In Aim 2, we will examine the role of the 3'-untranslated region (UTR) of the PKG-I mRNA in stabilizing both the message and the protein. Our hypothesis is that specific AU-rich binding proteins stabilize PKG-I mRNA and that inflammatory cytokines down-regulate these stabilizing proteins thus producing a destabilized mRNA and suppressed protein expression. In both of these mechanisms, PKG-la and I¿ may be down-regulated in response to inflammation and increased cytokine production. These effects may facilitate the modulation of contractile VSMC to synthetic VSMC.

描述（由申请人提供）：I 型环 GMP 依赖性蛋白激酶 (PKG-I) 介导血管平滑肌细胞 (VSMC) 中的一氧化氮 (NO) 信号传导，PKG-la 和 PKG-I¿ ，被认为介导 NO 依赖性平滑肌松弛、细胞生长抑制和收缩蛋白基因表达增加。然而，已知白细胞介素-1 (IL-1) 等炎症细胞因子可刺激 VSMC 生长并阻断收缩蛋白。我们的实验室表明，炎性细胞因子也会抑制 VSMC 中的 PKG-I 表达，表明这些细胞因子的至少一种作用机制是抑制 PKG-I 并诱导纤维增殖性 VSMC 表型。本提案将探讨细胞因子抑制 VSMC 表达 PKG-I 的机制。这是一项基础科学提案，旨在确定 VSMC 中调节这些细胞中 PKG-I 表达的分子机制。中心假设是 IL-。 1 和其他细胞因子通过两种主要机制下调 PKG-I 表达：首先，通过增加细胞中 cGMP 的产生（通过和诱导 II 型 NO 合酶或 iNOS），PKG-I目标 1 将检查 PKG-I 泛素化的机制。 cGMP 的结合，特别是与 PKG-1a 同种型的结合，诱导激酶调节域的自身磷酸化，从而靶向其进行泛素化。将鉴定自磷酸化位点、泛素化位点和结合自磷酸化 PKG-la 的 E3 连接酶。将评估 PKG-la 下调对 VSMC 表型特性的影响。 PKG-I mRNA 的 3'-非翻译区 (UTR) 可以稳定信息和蛋白质，我们的假设是富含特定 AU 的结合蛋白。 PKG-I mRNA 和炎症细胞因子下调这些稳定蛋白，从而产生不稳定的 mRNA 并抑制蛋白表达。在这两种机制中，PKG-la 和 I¿这些效应可能会因炎症反应而下调，并可能促进收缩性 VSMC 向合成 VSMC 的调节。