Control of Cytoxine mRNA Stability by AUF1

描述（由申请人提供）： 该提议针对一种重要但知之甚少的基因控制机制，即哺乳动物细胞中短寿命细胞因子和原癌基因mRNA的靶向降解，其由这些mRNA的3'非翻译区（3' UTR）中的富含A+ U的元件（ARE）促进。 这项更新申请建立在我们在前一个项目期间的工作基础上，旨在表征一种名为AUF 1的ARE结合蛋白的功能，该蛋白促进ARE-mRNA的快速衰变。 目的1将通过质谱鉴定和表征新的AUF 1相互作用蛋白，验证体内相互作用，并研究这些相互作用在ARE-mRNA衰变中的功能重要性。 迄今为止，仅鉴定了几种AUF 1相互作用蛋白。 由于AUF 1缺乏酶活性，因此AUF 1通过与其他蛋白质的相互作用促进或调节细胞因子和原癌基因ARE-mRNA的衰变。 目的2将分析AUF 1在促进或调节内源性和报告基因ARE-mRNA在分离的原代小鼠脾和胸腺淋巴细胞中的快速周转中的功能，其中AUF 1主要表达。 我们最近开发的AUF 1基因敲除小鼠，并研究了AUF 1的表达主要定位于脾和胸腺淋巴细胞，使得研究AUF 1在其真实表达细胞类型和器官中的分子和生化功能成为可能。 目的3将表征小鼠中AUF 1的功能。 目前对AUF 1在动物中的作用了解甚少。 通过比较野生型和AUF 1基因敲除小鼠，研究AUF 1在促进或调节胸腺和脾脏中淋巴细胞细胞因子mRNA稳定性方面的功能。研究还将在不同的相关实验环境中检查AUF 1敲除小鼠的表型。

DESCRIPTION (provided by applicant): This proposal is directed to an important but very poorly understood mechanism of gene control, the targeted degradation of short-lived cytokine and proto-oncogene mRNAs in mammalian cells, which is promoted by an A+U-rich element (ARE) in the 3' untranslated region (3'UTR) of these mRNAs. This renewal application builds on our work during the previous project period and seeks to characterize the function of one ARE-binding protein known as AUF1, which promotes rapid decay of ARE-mRNAs. Aim 1 will identify and characterize new AUF1 interacting proteins by mass spectrometry, verify interactions in vivo, and investigate the functional importance of these interactions in ARE-mRNA decay. Only several of the AUFl-interacting proteins have been identified to date. Since AUF1 lacks enzymatic activity, it is through interactions with other proteins that AUF1 facilitates or regulates decay of cytokine and proto-oncogene ARE-mRNAs. Aim 2 will analyze the function of AUF1 in promoting or regulating the rapid turnover of endogenous and reporter ARE-mRNAs in isolated primary mouse spleen and thymus lymphocytic cells, where AUF1 is predominantly expressed. Our recent development of an AUF1 knockout mouse, and studies which localized AUF1 expression largely to splenic and thymic lymphocytes, makes it possible to investigate the molecular and biochemical functions of AUF1 in its authentic expressing cell type and organ. Aim 3 will characterize the function of AUF1 in the mouse. There is little if any understanding of the role of AUF1 in animals. By comparing wild type and AUF1 knockout mice, studies will investigate the function of AUF1 in promoting or regulating the stability of lymphocytic cytokine mRNAs in the thymus and spleen. Studies will also examine the phenotype of the AUF1 knockout mouse in different relevant experimental settings.