The Structure and Function of the CRTH2 PDG2 Receptor

CRTH2 PDG2 受体的结构和功能

基本信息

批准号：
6868511
负责人：
RICHARD M. BREYER
金额：
$ 37.75万
依托单位：
VANDERBILT UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-02-01 至 2010-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6868511
关键词：
asthma biological signal transduction cell migration computer simulation disease /disorder model genetically modified animals laboratory mouse ovalbumin point mutation prostaglandin receptor protein sequence receptor binding receptor expression site directed mutagenesis tissue /cell culture

项目摘要

DESCRIPTION (provided by applicant): Prostaglandin D2 (PGD2) is a major cyclooxygenase metabolite, and its release has been hypothesized to contribute to the inflammation and increased airway hyperreactivity observed in asthma. PGD2 appears to act in part through a recently cloned GPCR designated CRTH2. CRTH2 mRNA expression pattern is consistent with an important role for this receptor in the etiology of allergic disease. The principal hypothesis of this proposal is that critical PGD2 evoked changes in the immune inflammatory response are mediated, at least in part, by CRTH2-evoked responses. We further propose that some of the effects of PGD2 metabolites including PGJ2 and 15d PGJ2 are mediated via the CRTH2 receptor. To test this hypothesis we propose in Specific Aim 1 to define the pharmacology of the mouse CRTH2 receptor. We will express the CRTH2 receptor in cell culture and determine its ligand binding and signal transduction properties. In Specific Aim 2 we will identify amino acid residues critical for ligand binding and signal transduction by site directed mutagenesis. Using modeling and molecular dynamics simulations as a guide, we will introduce point mutations into the CRTH2 receptor, and express mutant receptors in cell culture systems. In Specific Aim 3 we will explore whether PGD2 modulates inflammatory effects and/or bronchoconstriction in mouse models of asthma via the CRTH2 receptor. We will analyze ovalbumin (OVA) allergic sensitization, a TH2 type immune model, in CRTH2 knockout mice and compare this with DP null animals. We further propose to cross the CRTH2 null mice with DP null mice to test the effect of loss of both PGD2 receptors. Completion of these studies should aid in the elucidation of the physiologic role of PGD2 in cellular migration and infiltration in allergic airway disease and will provide insight as to the role of this receptor in mouse models of allergic inflammation.

描述（由申请人提供）：前列腺素D2（PGD2）是主要的环氧酶代谢产物，其释放已被认为有助于炎症并增加气道高反应性。 PGD2似乎部分通过最近克隆的GPCR指定的CRTH2起作用。 CRTH2 mRNA表达模式与该受体在过敏性疾病的病因中的重要作用一致。该提议的主要假设是，关键的PGD2引起的免疫炎症反应的变化至少部分通过CRTH2诱发的反应介导。我们进一步提出，PGD2代谢产物（包括PGJ2和15D PGJ2）的某些作用是通过CRTH2受体介导的。为了检验该假设，我们在特定目标1中提出了定义小鼠CRTH2受体的药理学。我们将在细胞培养中表达CRTH2受体，并确定其配体结合和信号转导特性。在特定目标2中，我们将确定对位点定向诱变对配体结合和信号转导至关重要的氨基酸残基。使用建模和分子动力学模拟作为指导，我们将在CRTH2受体中引入点突变，并在细胞培养系统中表达突变受体。在特定目标3中，我们将探索PGD2是否通过CRTH2受体在哮喘的小鼠模型中调节炎症作用和/或支气管收缩。我们将在CRTH2基因敲除小鼠中分析椭圆蛋白（OVA）过敏性敏化（一种Th2型免疫模型），并将其与DP无效动物进行比较。我们进一步建议将CRTH2无效的小鼠与DP无效小鼠穿越CRTH2 NULL小鼠，以测试两种PGD2受体丧失的影响。这些研究的完成应有助于阐明PGD2在过敏性气道疾病中PGD2在细胞迁移和浸润中的生理作用，并将为该受体在过敏性炎症的小鼠模型中的作用提供见解。