Profiling and Dissecting the Dynamic Regulation of RNA Editing

非常普遍的RNA编辑和修饰(构成表位转录组) 有助于转录组的多样性和灵活性。其中最常见的一种类型是腺苷到- 肌苷(A-to-I)，由作用于RNA的腺苷脱氨酶(ADAR)家族催化。 Adar与双链RNA(DsRNA)结合，并将特定的腺苷脱氨为肌苷，肌苷是 被细胞机器读作鸟苷。ADAR的丢失导致一系列神经系统疾病 在模式生物中证明的表型。RNA编辑级别的改变与 神经性疾病的数量。RNA编辑的规则是非常动态的，在不同的 组织，并处于不同的发育阶段。虽然我们之前由这笔赠款资助的工作导致了 在组织水平上的动态调节的前所未有的视角，这些测量代表了 编辑级别变化很大或基本相同的许多单元格的平均值。我们缺少一个好的 了解不同细胞类型甚至单个细胞之间的RNA编辑差异有多大。 特别是在神经元高度可塑性和存在多种细胞类型的大脑中，RNA编辑可能会 在微调调节大脑功能和神经元连接的mRNA信息方面发挥作用 在一生中。在这项工作中，我们旨在了解RNA编辑的动态调节 前所未有的深度。首先，我们将分析苍蝇、小鼠、 和人类。我们还将研究编辑在发展阶段和年中的变化 在模式生物中对环境刺激的反应。第二，我们将分配RNA的功能 利用高度自动化和灵敏的表型对果蝇不同神经回路的编辑 化验。最后，为了机械地剖析动态规则，我们将对其进行识别和验证 其他RNA编辑调节器，并确定这些调节器影响的机制 在果蝇和哺乳动物中进行编辑。这项工作将提供对动态的更深入的理解 不同神经细胞类型中A-to-I RNA编辑的调节以及RNA的作用 在大脑功能中进行编辑。

The remarkably prevalent RNA editing and modifications (which constitute the epitranscriptome) contribute to transcriptome diversity and flexibility. One of the most common types is adenosine-to- inosine (A-to-I), catalyzed by the adenosine deaminase acting on RNA (ADAR) family of enzymes. ADAR binds to double-stranded RNA (dsRNA) and deaminates specific adenosine to inosine, which is read as guanosine by the cellular machinery. Loss of ADAR leads to a range of neurological phenotypes as demonstrated in model organisms. Alteration of RNA editing levels is associated with a number of neurological disorders. The regulation of RNA editing is very dynamic, varying in different tissues and at different developmental stages. While our previous work funded by this grant led to an unprecedented view of dynamic regulation at the tissue level, the measurements represent an average of many cells with widely variable or largely equal editing levels. We lack a good understanding of how much RNA editing varies between different cell types or even single cells. Particularly in the brain, where neurons are highly plastic and many cell types exist, RNA editing may play a role in fine-tuning mRNA messages that modulate brain function and neuronal connectivity throughout life. In this work, we aim to understand the dynamic regulation of RNA editing at an unprecedented depth. First, we will profile RNA editing in different neuronal cell types in flies, mice, and humans. We will also examine the changes of editing during developmental stages and in response to environmental stimuli in model organisms. Second, we will assign functions of RNA editing in different neural circuits in Drosophila using a highly automated and sensitive phenotypic assay. Finally, to mechanistically dissect the dynamic regulation, we will identify and validate additional RNA editing regulators and determine the mechanisms by which these regulators influence editing in Drosophila and mammals. This work will provide a deeper understanding of the dynamic regulation of A-to-I RNA editing in different neuronal cell types and shed light on the role of RNA editing in brain function.