Movement of RNA between animal cells

描述（由申请人提供）：使用双链RNA （dsRNA）触发RNA干扰，从而沉默匹配的疾病基因，是许多人类疾病的治疗方法。然而，很难将这些基于rna的药物输送到人体细胞中。相反，当dsRNA被引入植物和一些动物（如秀丽隐杆线虫）的一个细胞时，由于dsRNA形式的移动RNA在细胞之间的运输，远距离细胞中的基因也被沉默。这种RNA在细胞间的直接运输代表了一种细胞间信号传导的新形式，它是在线虫和植物的基因沉默研究中偶然发现的。在细胞核中转录的RNA是如何从动物细胞中分泌出来，以使远处细胞中的靶基因沉默的，目前还不清楚。对秀丽隐杆线虫的研究发现了摄取移动rna所需的保守蛋白，这表明类似的机制可能存在于包括哺乳动物在内的其他动物中。有趣的是，细胞外rna群体已经在人类血液中被发现，并被用作评估内脏疾病状态的诊断工具，内脏可能是这些rna的来源。这项提议的目标是利用线虫中可用的工具来揭示dsRNA如何被修饰以产生从细胞分泌的可移动rna，并分析控制这些rna从细胞输出的基因。利用可用的突变体，我们将采用生化和遗传方法来鉴定修饰的dsRNAs和由此产生的移动rna。我们将使用我们分离出的在rna细胞间运输中有缺陷的新突变体来发现控制这一过程的其他基因并分析它们。这些目标的完成可以揭示RNA如何被修饰以从动物细胞输出，并可以开始通过RNA在动物细胞之间的直接运输来组装细胞间信号通路。这些研究也与了解完全未知的细胞外rna生物学有关，可以成为内部器官疾病的有力诊断工具。最后，如果我们了解对dsRNA和其他细胞机制的什么修饰能够使移动RNA有效地进入秀丽隐杆线虫细胞，我们就可以设计类似的修饰dsRNA，以便有效地递送到人类细胞中进行RNA干扰治疗。

DESCRIPTION (provided by applicant): The use of double-stranded RNA (dsRNA) to trigger RNA interference and thereby silence matching disease genes is being pursued as a therapeutic approach for many human diseases. However, it is difficult to deliver these RNA-based drugs into human cells. In contrast, when dsRNA is introduced into one cell in plants and in some animals such as the worm C. elegans, genes in distant cells are also silenced due to the transport between cells of forms of dsRNA called mobile RNA. This direct transport of RNA between cells represents a novel form of intercellular signaling that was accidentally discovered as part of gene silencing studies in the worm C. elegans and in plants. How RNA that is transcribed in the nucleus is secreted from animal cells to silence a target gene in distant cells s not well understood. Studies in C. elegans identified conserved proteins required for the uptake of mobile RNAs suggesting that similar mechanisms may exist in other animals, including mammals. Intriguingly, populations of extracellular RNAs have been found in human blood and are being pursued as diagnostic tools to assess the disease state of internal organs, which are presumably the source of such RNAs. The goals of this proposal are to use the tools available in C. elegans to uncover how dsRNA is modified to generate mobile RNAs that are secreted from cells and to analyze genes that control the export of such RNAs from cells. Using available mutants, we will take biochemical and genetic approaches to identify modified dsRNAs and the mobile RNAs that result from them. We will use new mutants we have isolated that are defective in the intercellular transport of RNAs to discover additional genes that control this process and analyze them. The completion of these aims can reveal how RNAs are modified for export from animal cells and can begin to assemble the pathway for intercellular signaling by the direct transport of RNA between animal cells. These studies are also relevant to understand the entirely unknown biology of extracellular RNAs, which can become powerful diagnostic tools for diseases of internal organs. Finally, if we understand what modifications to dsRNA and other cellular machinery enable the efficient entry of mobile RNAs into C. elegans cells, we can design similar modified dsRNAs for efficient delivery into human cells for RNA interference-based therapy.