CCSP Promoter Function and Tumor Necrosis Factor

描述(由申请人提供)：本修订申请旨在阐明急性呼吸道感染和炎症期间肺特异基因转录调控的机制。感染期间肺功能的动态平衡可能受到关键的肺特异基因的调节。重要的肺内稳态蛋白，包括表面活性蛋白(SP)基因和Clara细胞分泌蛋白(CCSP)在急性感染后显著减少。初步数据表明，CCSP基因的表达通过减弱启动子功能而下调，特别是在包含几个关键的反式激活结合位点的近端反式激活启动子区域。同样，新的发现暗示了炎症介质，特别是肿瘤坏死因子-α，在宿主对急性感染的反应中调节肺基因转录的作用。CCSP和SP基因的近端启动子元件有很强的相似性，提示这两个基因的转录调控机制在正常和病变肺中可能是协调的。使用CCSP转录调控作为模型，现在可以使用转基因方法在体外和体内系统中研究肺特异基因的转录调控和DNA-蛋白质相互作用。具体地说，这项应用旨在描述CCSP启动子区域的DNA-蛋白质相互作用，并阐明转录因子调节机制，在宿主对急性感染的反应中，转录因子通过特定的炎症介质异常调节肺特异基因的表达。利用CCSP启动子调控作为了解小鼠肺转录调控的模型具有明显的优势，包括能够发展转基因动物来研究肺特异的转录调控和体内DNA-蛋白质的相互作用。使用这种方法，可以在体内评估病原体或炎症介质对肺特异基因转录调控的机制；这一策略通常不适用于其他转录调控基因的研究。阐明DNA-蛋白质相互作用和转录因子调节减弱肺特异性转录可能对了解严重呼吸道感染和炎症时肺功能下降的机制具有重要意义。

DESCRIPTION (provided by applicant): This revised application seeks to elucidate the mechanisms of transcriptional regulation of lung-specific genes during acute respiratory infection and inflammation. Homeostasis of lung function during infection is likely regulated by critical lung-specific genes. Important lung homeostatic proteins, including surfactant protein (SP) genes and the Clara cell secretory protein (CCSP) are markedly decreased following acute infection. Preliminary data herein indicate that CCSP gene expression is down regulated through attenuation of promoter function, specifically in the proximal transactivating promoter region containing several critical transactivating binding sites. Likewise, new findings implicate the role of inflammatory mediators, in particular TNF-alpha, in the regulation of lung gene transcription during the host response to acute infection. Strong similarities exist in the proximal promoter elements of CCSP and SP genes, suggesting that mechanisms of transcriptional regulation of these genes may be coordinated both in normal and diseased lung. Using CCSP transcriptional regulation as a model, transcriptional regulation, and DNA-protein interactions of lung-specific genes can now be studied in both in vitro and in vivo systems using a transgenic approach. Specifically, this application proposes to delineate the DNA-protein interactions in the CCSP promoter loci and elucidate mechanisms of transcription factor regulation that aberrantly regulate lung-specific gene expression by specific inflammatory mediators during the host response to acute infection. The use of CCSP promoter regulation as a model for understanding transcriptional regulation in the mouse lung has distinct advantages, including the ability to develop transgenic animals for the study of lung-specific transcriptional regulation and DNA-protein interactions in vivo. Using this approach, the mechanisms of transcriptional regulation of lung-specific genes by pathogens or inflammatory mediators can be assessed in vivo; a strategy that is often unavailable for the study of other transcriptionally regulated genes. Elucidation of the DNA-protein interactions and transcription factor regulation that attenuate lung-specific transcription will likely be important to understand the mechanisms of diminished lung function during severe respiratory infections and inflammation.