HuR in Allergic Asthma

描述（由申请人提供）：由于未知的原因，哮喘的患病率和严重程度一直在增加。尽管我们对其病理生理学的理解仍然很差，但人们普遍认为哮喘是一种炎症性疾病，CD4+ T细胞分泌Th2细胞因子已被确定为其发展的主要罪魁祸首。这些基因中有许多是转录后调控的，但它们的调控还没有得到很好的理解。我们提出了一个新的范式，即转录后操纵子假说，该假说认为RNA结合蛋白协调调节生物相关分子的表达。我们的假设是，RNA结合蛋白HuR在变应性气道炎症中协调调节Th2极化和细胞因子基因表达。HuR是在3'非翻译区含有富AU不稳定元素（AREs）的不稳定mrna的主要稳定剂。所有Th2细胞因子和90%的细胞因子和趋化因子都有AREs。1. 确定HuR调节对淋巴细胞Th2极化和细胞因子产生的影响。我们将使用慢病毒载体在CD4+ T细胞中低表达HuR，并检测Th1/Th2极化和细胞因子基因表达。2. 确定HuR过表达和过表达在小鼠变应性气道炎症模型中的作用。我们将测试改变HuR水平是否会改变过敏性气道炎症动物模型中的哮喘发展。3. HuR介导的过敏性炎症是否与microrna有关？我们将使用阵列技术从卵致敏动物的肺中分离和鉴定microrna。我们的方法将为哮喘相关的促炎基因的识别和调控提供更全面的理解。更好地了解促炎基因在转录后水平的调控可能会导致治疗哮喘的靶向治疗。公共卫生相关性：世界范围内过敏和哮喘发病率和流行率上升的原因目前尚不清楚。转录后基因调控和microrna方面令人兴奋的新发现可能会对我们对过敏原驱动哮喘的理解产生广泛的影响。这一建议的目的是为了更好地理解细胞因子基因是如何在转录后水平调控的。这将极大地帮助我们了解疾病的发病机理和治疗方法，并对公众健康产生直接影响。小灵通398/2590 （Rev. 09/04）第15页延续格式页

DESCRIPTION (provided by applicant): Asthma has been increasing in prevalence and severity for unknown reasons. Though our understanding of the pathophysiology remains poor, it is widely accepted that asthma is an inflammatory disease and CD4+ T cells elaborating Th2 cytokines have been identified as major culprits in its development. Many of these genes are posttranscriptionally regulated but their regulation is not well understood. We have developed a new paradigm, the posttranscriptional operon hypothesis, which states that RNA binding proteins are coordinately regulating the expression of biologically related molecules. Our hypothesis is that the RNA binding protein, HuR, is coordinately regulating Th2 polarization and cytokine gene expression in allergic airway inflammation. HuR is a major stabilizer of labile mRNAs containing AU rich instability elements (AREs) in their 3' untranslated regions. All the Th2 cytokines and 90% of cytokines and chemokines have AREs. 1. Determine effects of HuR modulation upon Th2 polarization and cytokine production in lymphocytes. We will employ lentiviral vectors to under-express HuR in CD4+ T cells and assay Th1/Th2 polarization and cytokine gene expression. 2. Determine role of HuR over-expression and under-expression in murine models of allergic airway inflammation. We will test whether altering HuR levels will modify asthma development in animal models of allergic airway inflammation. 3. Does HuR mediated allergic inflammation involves microRNAs? We will isolate and identify microRNAs from lungs of ova sensitized animals using arrays. Our approach will provide a fuller understanding of the identity and regulation of proinflammatory genes involved in asthma. Better understanding of proinflammatory gene regulation at the posttranscriptional level may potentially lead to targeted therapies to treat asthma. PUBLIC HEALTH RELEVANCE: The reasons for the increasing incidence and prevalence of allergies and asthma worldwide are presently unknown. Exciting new discoveries in posttranscriptional gene regulation and microRNAs potentially may have broad impacts on our understanding of allergen driven asthma. The aim of this proposal is to better understand how cytokine genes are regulated at the posttranscriptional level. This would greatly aid in our understanding of disease pathogenesis and treatment and have a direct impact on public health. PHS 398/2590 (Rev. 09/04) Page 15 Continuation Format Page