Using Structuring Interacting RNAs (sxRNAs) as microRNA Inhibitors

描述（由申请人提供）：我们建议为科学家开发一种跨分子RNA开关，以负面影响内源性microRNA的活性，用作分子工具或治疗剂，即抗miR。自从发现miRNA以来，有效的抗miR的产生一直很重要，首先是研究和验证miRNA相互作用，其次是作为治疗工具。但是，创造有效的anti-miR并不简单。乍看之下，一条长度匹配、序列完全互补的RNA链可能是对抗特定miRNA的理想抗miR，但完全互补的序列会诱导RISC复合物并被切割，从而使单独的策略无效。虽然抗miR的骨架可以被修饰，但这些修饰不能完全解决互补性和切割的这种权衡，并给抗miR的任何治疗用途增加了肝毒性问题。我们一直在研究我们称之为“结构相互作用RNA”（或sxRNA），并认为sxRNA是一种转录后调节机制，调节RNA结合蛋白与mRNA的相互作用。这基本上是一种新的反式作用RNA-RNA相互作用，形成三向连接。该方法具有用作抗miR的三个优点：（1）在miRNA相互作用的边界内存在茎环消除了对切割的担忧，（2）茎环的侧翼可以与miRNA完美互补以增加结合，以及（3）三向连接似乎是非常稳定的结构。我们的目标是使用sxRNA优化抗miR，并针对其他市售抗miR测试最佳候选物。使用sxRNA作为分子工具在产品水平上的成功应该使该技术具有更多的用途。

DESCRIPTION (provided by applicant): We propose developing a trans-molecular RNA-switch for scientists to negatively affect the activity of endogenous microRNA for use as a molecular tool or therapeutic, an anti-miR. Since the discovery of miRNA, the creation of effective anti-miRs has been important, first to study and verify miRNA interactions, and, secondly, as a therapeutic tool. But, creating an effective anti-miR is not straightforward. At firt glance, one would thing that a strand of RNA in matching length and perfectly complementary in sequence would be the ideal anti-miR to fight for the attention of a particular miRNA and effectively neutralize it. However, a perfectly complementary sequence would induce the RISC complex and get cleaved rendering that strategy alone ineffective. While the backbone of the anti-miR can be modified, those modifications do not completely resolve this trade-off in complementariness and cleavage and add hepatoxicity issues to any therapeutic use of anti-miRs. We have been studying what we call "structurally interacting RNA" (or sxRNA) and believe sxRNA to be a post-transcriptional regulatory mechanism that regulates RNA Binding Protein interactions with mRNA. This is essentially a novel trans-acting RNA-RNA interaction forming a three way junction. This approach has three advantages for use as an anti-miR: (1) the presence of a stem loop within the bounds of the miRNA interaction eliminates concerns about cleavage, (2) the flanks of the stem loop can be perfectly complementary to an miRNA to increase binding and (3) three way junctions appear to be very stable structures. Our goal with this proposal is optimize an anti-miR using sxRNA and test the best candidate against other commercially available anti-miRs. Success at the product level using sxRNA as a molecular tool should ideally position the technology for additional uses.