Basis of Variability of Lung GPCR Signaling

肺 GPCR 信号传导变异的基础

• 批准号: 6796008
• 负责人: Stephen B Liggett
• 金额: $ 38.38万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2005-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6796008
• 关键词: DNA; G protein; biological signal transduction; genetic polymorphism; genetic regulation; genetic screening; genotype; haploidy; human genetic material tag; lung; population genetics; receptor coupling; receptor expression; recombinant proteins; respiratory pharmacology; tissue /cell culture

DESCRIPTION (provided by applicant): Many major signaling events in the lung are carried out by the superfamily of G-protein coupled receptors (GPCRs). These include bronchial smooth muscle relaxation and contraction, mucous secretion, ciliary beat frequency, inflammation, immune cell trafficking, pulmonary vascular tone and permeability, and alveolar fluid and electrolyte transport, as well as many yet to be defined functions. Approximately 75 GPCRs are estimated to be expressed in human lung. Within the next five years, the great majority of all therapeutic agents will target GPCRs. However, the physiologic, pathologic, and pharmacologic behavior of GPCR signaling displays substantial interindividual variability which is thought to be due to common variants (polymorphisms) of the genes encoding these receptors. Such polymorphisms have been estimated to account for as much as 50% of the variability in the response to therapeutic agonists and antagonists targeted to GPCRs. Indeed, with just one GPCR, the (2-adrenergic receptor, we have shown that coding and promoter polymorphisms alter receptor expression, function, and regulation in vitro in cells, and in asthmatic patients, they are associated with clinical phenotypes and the response to beta-agonist therapy. The long-term goals of this proposal are to identify polymorphisms of up to 20 pulmonary GPCR genes, and by the use of recombinant expression techniques to delineate their biochemical and pharmacologic impact on cellular signaling relevant to lung homeostasis and pathobiology. In Aim 1, the polymorphisms of these 20 GPCR genes will be delineated in the promoter, 5' untranslated, coding, intron/exon junctions, and 3' untranslated regions from genomic DNA samples from a cohort of 60 ethnically diverse individuals. In Aim 2, the common combinations of polymorphisms (haplotypes) will be delineated in the population. In Aim 3, constructs will be developed and model cell systems utilized for recombinant expression of GPCR haplotypes to determine the biological effects of polymorphisms on receptor expression, signaling, or regulation. These studies will provide the basis for interindividual susceptibility and therapeutic responsiveness, the variability in pathobiology, and the potential for developing new treatment strategies, for a diverse range of lung diseases including asthma, pulmonary hypertension, pneumonia, pulmonary fibrosis, COPD, and pulmonary edema.

描述(申请人提供)：肺中的许多主要信号事件是由G蛋白偶联受体(GPCRs)超家族执行的。这些包括支气管平滑肌松弛和收缩、粘液分泌、纤毛跳动频率、炎症、免疫细胞运输、肺血管张力和通透性、肺泡液和电解质运输以及许多尚未确定的功能。据估计，大约有75个GPCRs在人肺中表达。在未来五年内，绝大多数治疗药物将针对GPCRs。然而，GPCR信号的生理、病理和药理学行为表现出很大的个体间差异，这被认为是由于编码这些受体的基因的共同变异(多态)所致。据估计，在针对GPCRs的治疗激动剂和拮抗剂的反应中，这种多态可以解释高达50%的变异性。事实上，只有一种GPCR，即(2-肾上腺素能受体)，我们已经证明编码和启动子多态在细胞内改变受体的表达、功能和体外调节，在哮喘患者中，它们与临床表型和对β-激动剂治疗的反应有关。这项建议的长期目标是识别多达20个肺GPCR基因的多态性，并通过使用重组表达技术来描述它们对与肺内稳态和病理生物学相关的细胞信号的生化和药理学影响。在目标1中，将从60个不同种族的个体的基因组DNA样本中，在启动子、5‘非翻译区、编码区、内含子/外显子连接区和3’非翻译区描绘这20个GPCR基因的多态。在目标2中，将描述种群中常见的多态组合(单倍型)。在目标3中，将开发构建并利用模型细胞系统重组表达GPCR单倍型，以确定多态对受体表达、信号或调节的生物学效应。这些研究将为包括哮喘、肺动脉高压、肺炎、肺纤维化、慢性阻塞性肺疾病和肺水肿在内的各种肺部疾病的个体间易感性和治疗反应性、病理生物学的变异性以及开发新的治疗策略的潜力提供基础。