Structural and Mechanistic basis for RNA Silencing

项目摘要/摘要 人体内几乎每个细胞都含有一组可编程的基因沉默蛋白，名为 阿尔加索特。ArgAerte蛋白的天然功能是通过microRNAs介导基因调控 (MiRNAs)，在不同的生理过程中有助于细胞内稳态的小RNA，如 干细胞维持、受精和心脏发育。人类Argoanut2(Ago2)也可以 通过引入小干扰RNA用于实验和治疗目的 (SiRNAs)，与Ago2结合，用于指导靶基因的沉默。最重要的是 这项研究的目标是了解小RNA是如何产生的，并被ArgAerte用来沉默 基因。这项工作的合理动机是，对沉默过程的更好理解将 加强在治疗环境中利用这些机制的努力，并为疾病治疗提供信息 由miRNA功能异常引起的状态。此外，由于miRNAs在许多方面都有贡献 人类生物学，对功能理解的改进将使研究人员能够从不同方面进行研究 人类的健康和疾病。主要项目包括：1)确定人类骰子的结构， 催化miRNA生物发生的最后一步的酶，目的是了解迪格尔是如何 突变导致多种破坏性的人类癌症；2)确定miRNA的决定因素 靶向，目的是提高对miRNA靶标的预测；3)研究miRNA的结构 诱导沉默复合体，重点是低估液：液相分离的贡献 对miRNAs的基因调控；4)建立siRNAs切割mrna的结构基础，与 目的是为合理设计治疗性siRNA提供新的见解。合并后的研究是 预计将提供必要的基础知识来破译和控制阿加宇航员- 介导对人类基因表达的调控。

Project Summary/Abstract Nearly every cell in the human body contains a set of programmable gene-silencing proteins named Argonaute. The natural function of Argonaute proteins is to mediate gene-regulation by microRNAs (miRNAs), small RNAs that contribute to cellular homeostasis during diverse physiological process, such as stem cell maintenance, fertilization, and heart development. Human Argoanute-2 (Ago2) can also be harnessed for experimental and therapeutic purposes through the introduction of small interfering RNAs (siRNAs), which are bound by Ago2 and used to direct the silencing of targeted genes. The overarching goal of this research is to understand how small RNAs are generated and used by Argonaute to silence genes. The rational motivating this work is that improved understanding of silencing processes will empower efforts to harness these mechanisms in a therapeutic setting and inform treatment of disease states resulting from aberrant miRNA function. Additionally, because miRNAs contribute in many facets of human biology, improvements in understanding function will enable researchers studying diverse aspects of human health and disease. Major projects include: 1) determining the structure of human Dicer, the enzyme that catalyzes the final step of miRNA biogenesis, with the goal of understanding how Dicer mutations drive diverse and devastating forms of human cancer; 2) identifying determinants of miRNA targeting with the goal of improving prediction of miRNA targets; 3) investigate the structure of miRNA- induced silencing complexes with a focus on understating how liquid:liquid phase separation contributes to gene-regulation by miRNAs; 4) establish the structural basis for mRNA cleavage by siRNAs, with the goal of providing novel insights for rational design of therapeutic siRNAs. The combined studies are expected to provide fundamental knowledge necessary for deciphering and controlling Argonaute- mediated regulation of human gene expression.