Assessing the role of circRNAs in memory consolidation

项目摘要 在不同的RNA种类中，环状RNA（circRNA）特别迷人，因为它们是 高度抗降解。这类新的RNA在多种真核生物中表达， 不同的细胞类型，包括神经元，并证明了哺乳动物之间的保护。此外，它们是 独立于其同源线性同种型调节。从机制上讲，它们可以起到miRNA海绵的作用， 调节剪接和转录，与RNA结合蛋白结合。一些circRNA具有IRES，因此 可以翻译。然而，circRNA是否在长期记忆中发挥关键作用尚不清楚。因此 对circRNA对LTM的贡献的深入理解有望提供机制见解， 鉴定新的LTM调节剂。为此，使用情境恐惧记忆作为LTM模型，我们有 进行了无偏分析，从齿状回（DG）亚区的circRNAss的表达， 小鼠海马。对DG中差异表达的circRNA的初步分析表明， 在恐惧条件动物中上调（padj<0.05）的三种不同circRNA的鉴定 与单独的背景或单独的电击对照相比。这些结果表明，circRNA受到 学习过程中的转录变化。这一提议的核心假设是， 海马亚区特异性circRNA的变化介导背景恐惧的巩固 记忆为了验证这一假设，我们在这里提出进行无偏分析的时间调节， 情境恐惧条件反射后海马三突触回路中的circRNA表达，以及 差异表达的circRNA的功能解剖。我们预计， 该提案中概述的实验将揭示circRNA机制在长期记忆中的新作用 存储.

PROJECT SUMMARY Among different RNA species, circular RNAs (circRNAs) are particularly fascinating because they are highly resistant to degradation. This novel class of RNAs is expressed in a variety of eukaryotic organisms, in different cell types including neurons, and demonstrates conservation across mammals. Furthermore, they are regulated independently of their cognate linear isoforms. Mechanistically they can function as miRNA sponges, regulate splicing and transcription, bind to RNA binding proteins. Some circRNAs possess IRES and therefore could be translated. However, whether circRNAs play a critical role in long-term memory is unknown. Thus, a deep understanding of the contribution of circRNAs to LTM is expected to provide mechanistic insights and identify novel regulators of LTM. To this end, using contextual fear memory as a model for LTM, we have carried out an unbiased analysis of expression of circRNAss from the dentate gyrus (DG) subregion of the mouse hippocampus. Preliminary analysis of differentially expressed circRNAs in DG has resulted in the identification of three different circRNAs that are upregulated (padj<0.05) in fear-conditioned animals compared to context alone or shock alone controls. These results suggest that circRNAs are subjected to transcriptional changes during learning. The central hypothesis of this proposal is that the transcriptional changes in specific circRNAs in hippocampal subregions mediate the consolidation of contextual fear memory. To test this hypothesis, we here propose to carry out unbiased analysis of temporal regulation of circRNA expression in the tri-synaptic circuitry of the hippocampus following contextual fear conditioning, and functional dissection of differentially expressed circRNAs. We anticipate that successful completion of the experiments outlined in this proposal will unravel novel roles of circRNAs mechanisms in long-term memory storage.