Structural and Mechanistic basis for RNA Silencing

项目概要/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， 阿尔戈诺特。Argonaute蛋白的天然功能是通过microRNA介导基因调控 小分子RNA（miRNAs）是在不同的生理过程中有助于细胞稳态的小RNA， 如干细胞维持、受精和心脏发育。人Argoanute-2（Ago 2）也可以是 通过引入小干扰RNA用于实验和治疗目的， siRNA是由Ago 2结合并用于指导靶基因沉默的siRNA。总体 这项研究的目的是了解Argonaute如何产生和使用小RNA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 加强努力，在治疗环境中利用这些机制，并为疾病治疗提供信息 异常的miRNA功能导致的状态。此外，由于miRNAs在许多方面起作用， 人类生物学，理解功能的改善将使研究人员能够研究不同的方面 人类的健康和疾病。主要项目包括：1）确定人类Dicer的结构， 催化miRNA生物合成的最后一步的酶，目的是了解Dicer 突变驱动多种多样的和毁灭性的人类癌症形式; 2）确定miRNA的决定因素 靶向，目的是提高对miRNA靶点的预测; 3）研究miRNA的结构- 诱导沉默复合物，重点是了解液：液相分离如何有助于 4）建立siRNA切割mRNA的结构基础， 目的是为治疗性siRNA的合理设计提供新的见解。综合研究包括 有望为破译和控制阿尔戈诺特提供必要的基础知识- 介导的人类基因表达调控。

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.