Transcriptional Activation by Small RNA: Mechanism and Design Rules

描述(申请人提供)：本申请的目标是建立一种由小RNA介导的新的基因调控范例。直到最近，小RNA一直被认为主要作为一种进化保守的基因沉默机制(RNAi)的中介。我们和其他人发现，靶向基因启动子序列的小双链RNA(DsRNA)可以在转录水平上以序列特异性的方式诱导有效和持久的基因激活，我们称之为RNAa。尽管在活细胞中重新编程基因表达的潜力巨大，但RNAa的分子机制在很大程度上是未知的，靶标选择的规则仍然相当模糊。我们建议使用基因组、生物信息学和分子生物学方法的组合来解决以下问题：如何实现启动子靶向dsRNA的转录激活？涉及到的分子机器是什么？RNAa是细胞天然利用的生理功能吗？控制dsRNA启动子靶向的敏感性和特异性的一般规则是什么？了解RNAa的分子机制并将其建立为一种新的范式，可能会改变研究基因功能和治疗癌症等疾病的方式。 与公共卫生相关：RNAa可能是一种具有根本重要性的生物学机制。了解这一机制将具有改善公共卫生的巨大潜力。首先，RNAa可以为许多生理和疾病过程提供新的见解；其次，RNAa可以作为一种工具来询问基因功能并研究其在疾病中的作用；最后，RNAa可能成为许多疾病特别是癌症的传统基因治疗的有前途的替代品。

DESCRIPTION (provided by applicant): The goal of this application is to establish a new paradigm of gene regulation mediated by small RNA. Until recently, small RNAs have been thought to function mainly as the mediators of an evolutionally conserved gene silencing mechanism known as RNAi. We and others discovered that small double stranded RNA (dsRNA) targeting gene promoter sequence can induce potent and prolonged gene activation at the transcriptional level and in a sequence-specific manner, a phenomenon we termed RNAa. Despite the enormous potential for reprogramming gene expression in living cells, the molecular mechanism of RNAa is largely unknown and the rules for target selection are still quite obscure. We propose to use a combination of genomic, bioinformatic, and molecular biology approaches to address the following questions: How is transcriptional activation by promoter-targeted dsRNA achieved? What are the molecular machines involved? Is RNAa naturally exploited by cells for physiological function? What are the general rules governing the sensitivity and specificity of dsRNA-promoter targeting? Understanding the molecular mechanism of RNAa and establishing it as a new paradigm are likely to transform the way gene function is studied and diseases such as cancer are treated. PUBLIC HEALTH RELEVANCE: RNAa is potentially a biological mechanism of fundamental importance. Understand this mechanism will have enormous potential for improving public health. First, RNAa may provide new insight to many physiological and diseases processes; second, RNAa can be used as a tool to interrogate gene function and study their involvement in diseases; lastly, RNAa may serve as a promising surrogate for traditional gene therapy for many diseases especially cancer.