SnoRNA-guided modifications of mRNA

摘要 最近的研究表明，转录后的mRNA修饰可以调节基因的表达， 与细胞分化、发育和癌症有关。例如，M6A修改可以 调节信使核糖核酸生物学的基本方面，如剪接、稳定性和翻译。相比之下，更不用说 已知的是mRNA上的内部2‘-O-甲基化(Nm)。现在，使用遗传模型，我们的数据表明， 核仁RNAs(SnoRNAs)可以通过纤维蛋白(FBL)酶来引导mRNA的内部Nm修饰。我们的 研究结果还表明，Nm修饰可以调节体内的mRNA水平和蛋白表达。在这 应用，我们建议定义导致mRNA Nm修饰的机制，并理解 Nm如何调控基因表达。我们的长期目标是确定snoRNA如何引导对 信使核糖核酸影响基因表达、细胞生物学和生物体健康。这项提议的目标是具体地 确定snoRNA引导的Nm修饰如何调节Pxdn mRNA的表达。我们的中心假设 是Rpl13a snoRNAs引导FBL介导的Pxdn mRNA的Nm修饰，以及该修饰 增加信使核糖核酸丰度，但抑制蛋白质翻译。我们建议用以下方法来检验我们的假设 具体目标：(1)确定针对Pxdn mRNA的snoRNA(S)和蛋白质组分以进行Nm修饰； (2)确定snoRNA引导的Pxdn修饰如何调节RNA和蛋白质的表达；以及(3)发现 细胞中snoRNA引导的Nm修饰网络。这些目标的成功实现将为 第一次，Nm基因修饰是如何调控基因表达的。我们还希望我们的工作将定义 SnoRNAs在mRNA修饰中的新作用。因此，这项工作将开辟研究的新途径 RNA修饰和snoRNA生物学。

ABSTRACT Recent studies have demonstrated that post-transcriptional mRNA modifications can regulate gene expression, with implications for cellular differentiation, development, and cancer. For example, the m6A modification can regulate fundamental aspects of mRNA biology, such as splicing, stability, and translation. In contrast, much less is known about internal 2'-O-methylation (Nm) on mRNA. Now, using genetic models, our data suggest that small nucleolar RNAs (snoRNAs) can guide internal Nm modification of mRNA, via the enzyme fibrillarin (FBL). Our findings also suggest that Nm modification can regulate mRNA levels and protein expression in vivo. In this application, we propose to define the mechanisms that lead to Nm modification of mRNA, and to understand how Nm regulates gene expression. Our long-term goals are to determine how snoRNA-guided modifications of mRNA impact gene expression, cell biology, and organism health. The objective of this proposal is to specifically determine how snoRNA-guided Nm modification regulates the expression of Pxdn mRNA. Our central hypothesis is that Rpl13a snoRNAs guide FBL-mediated Nm modification of Pxdn mRNA, and that the modification increases mRNA abundance but inhibits protein translation. We propose to test our hypothesis with the following Specific Aims: (1) Define the snoRNA(s) and protein components that target Pxdn mRNA for Nm modification; (2) Define how snoRNA-guided modification of Pxdn regulates RNA and protein expression; and (3) Discover the network of snoRNA-guided Nm modifications in cells. Successful completion of these Aims will define, for the first time, how Nm modification of mRNA regulates gene expression. We also expect that our work will define a new role for snoRNAs in the modification of mRNA. As such, this work will open new avenues in the study of both RNA modifications and snoRNA biology.