Mechanisms of Gene Regulation by MicroRNAs

描述（由申请人提供）：这些研究将侧重于哺乳动物细胞中microRNA介导的mRNA降解，目的是了解microRNA加速脱氧腺苷化（作为其mRNA靶标降解的早期步骤）的机制，以及mRNA脱氧腺苷化和衰变对microRNA基因调控的贡献。使用培养的哺乳动物细胞作为模型系统和分子生物学方法作为分析工具，我们将研究有助于microRNA定向deadenylation的蛋白质，它们相互关联的方式，以及这些相互作用对miRNA功能的重要性。此外，我们将研究mRNA背景对microRNA影响mRNA稳定性的程度的影响。最后，我们将探讨microRNA识别mRNA中靶位点的机制。这些研究的结果应该增强我们对真核基因调控的广泛机制的认识，而这种机制目前还知之甚少。这些知识最终应该是有价值的理解疾病的病因，在某些情况下，被认为是与微小RNA功能的缺陷，并提高RNA干扰作为一种医学治疗的疗效。人们越来越意识到，人类细胞中数百种不同的microRNA在基因调控中起着关键作用。其他证据表明，microRNA对病毒感染很重要，microRNA功能的缺陷可能导致癌症和先天性畸形。拟议的研究最终将有助于了解与microRNA功能或功能障碍相关的疾病的病因，并提高基于小RNA分子的医学治疗的疗效。

DESCRIPTION (provided by applicant): These investigations will focus on microRNA-mediated mRNA degradation in mammalian cells, with the goal of understanding the mechanism by which microRNAs expedite deadenylation as an early step in the degradation of their mRNA targets and the contribution of mRNA deadenylation and decay to gene regulation by microRNAs. Using cultured mammalian cells as model systems and molecular biological methods as analytical tools, we will investigate the proteins that contribute to microRNA-directed deadenylation, the manner in which they associate with one another, and the importance of those interactions for miRNA function. In addition, we will examine the impact of mRNA context on the degree to which microRNAs influence mRNA stability. Finally, we will explore the mechanism by which microRNAs identify their target sites in mRNA. The results of these studies should enhance our knowledge of a widespread mechanism of eukaryotic gene regulation that presently is poorly understood. This knowledge should ultimately be of value for understanding the etiology of diseases thought in some instances to be related to defects in microRNA function and for improving the efficacy of RNA interference as a medical therapy. Lay language statement: There is growing awareness that the hundreds of distinct microRNAs in human cells play key roles in gene regulation. Additional evidence suggests that microRNAs are important for viral infection and that defects in microRNA function can contribute to cancer and congenital abnormalities. The proposed research should eventually be of value for understanding the etiology of diseases related to microRNA function or dysfunction and for improving the efficacy of medical therapies based on small RNA molecules.