Regulation of CD154 gene expression in vivo

描述(申请人提供)：CD154(CD40配体)表达被激活 CD154-CD40的相互作用已被证明在模型中具有有益的作用 自身免疫、炎症和移植物排斥反应。尽管如此，几乎没有什么 知道它的表达的调节，除了它似乎有 区别于细胞因子基因的几个特征。几项研究已经 表明了作为调节的主要决定因素的mRNA稳定性的重要性 CD154的表达。我们实验室的工作已经描绘出一个新的区域 调节嵌合报告基因表达的人CD154；UTR。这 顺式作用元件在小鼠和人类细胞中都是活性的，高度 保守的，并调解相当于富Au元素的影响(Aure) 它们已被证明是调节细胞因子的中心，如 肿瘤坏死因子-α和白介素2。仔细分析正常T淋巴细胞的mRNA稳定性 受技术考虑的限制。因此，我们建议测试一下 该顺式作用元件通过同源突变CD154基因表达 在小鼠生殖系中进行重组以产生一个小鼠系，在该系中 元素不再起作用。通过这种方法，我们将确定 CD154转录后调控在健康和健康中的作用 疾病，在肿瘤坏死因子-αAure突变小鼠身上得到了令人信服的证明。 因此，我们将创建一个模型系统来研究它的独特之处 监管，并可能开发新的方法来监管其 生物合成。

DESCRIPTION (provided by applicant): CD154 (CD40 ligan) expression by activated of CD 154-CD40 interactions has been shown to have salutary effects in models of autoimmunity, inflammation, and graft rejection. Despite this, little is known about the regulation of its expression, except that it appears to have several features that distinguish it from cytokine genes. Several studies have indicated the importance of mRNA stability as a major determinant in regulating CD154 expression. Work in our laboratory has delineated a novel region of the human CD 154 >UTR that regulates chimeric reporter gene expression. This cis-acting element is active in both murine and human cells, is highly conserved, and mediates effects equivalent to that of AU-rich elements (AURE) which have been shown to be central in the regulation of cytokines such as TNF-a and IL-2. Careful analysis of mRNA stability in normal T lymphocytes is limited by technical considerations. Therefore, we propose to test the role of this cis-acting element in CD 154 gene expression by mutating it by homologous recombination in the murine germ line to generate a mouse line in which this element is no longer functional. Through this approach, we will determine the role of post-transcriptional regulation of CD 154 expression in health and disease, as was compellingly demonstrated with the TNF-alpha AURE mutant mice. As a result, we will create a model system with which to study its unique regulation and possibly develop novel approaches to regulating its biosynthesis.