长非编码RNA的剪接调控机制研究

The recently increased application of transcriptome deep sequencing has led to an explosion in the number of documented non-coding RNAs (ncRNAs), including miRNA and long non-coding RNAs (lncRNAs), and also reveals biological functions of many lncRNAs. Usually containing introns, lncRNAs are the majority of identified new ncRNAs, which require pre-RNA splicing during the post-transcriptional processing. However, most recently studies have been focused on the identification of new lncRNAs and their functions, splicing regulation of these lncRNAs are remaining unclear. In this project, we will focus on lncRNAs from Drosophila and Human sapiens, using approaches from bioinformatics, RNA biology, molecular biology and transgenic flies to investigate the systematic differences of RNA splicing between non-coding genes and coding genes, to search for conserved and functional intronic RNA cis-elements, to elucidate splicing mechanism of some function-knowing lncRNAs and biological differences of their variant alternative splicing products. Therefore, ongoing of our project will provide deep insights of understanding the functional mechanism of lncRNAs and their regulation roles in the gene expression, development and differentiation.

近年来发现了包括长非编码RNA (lncRNA)在内的大量非编码基因,并在生物学功能研究上取得了重要进展。lncRNA占新发现RNA大多数，且通常具有需要通过RNA剪接去除的内含子。剪接是RNA加工和基因表达调控的重要步骤，然而已有研究集中在新lncRNA的寻找与功能鉴定上，其自身内含子如何去除和剪接水平上lncRNA表达调控机制尚未得到足够重视。本项目以果蝇与人类中lncRNA为对象，综合运用生物信息学，RNA分子生物学和转基因果蝇等技术，开展lncRNA基本剪接元件分析、内含子中保守顺式作用元件功能和选择性剪接调控机制等方面研究。预期这一研究将揭示ncRNA的剪接与编码基因剪接是否存在差异性，发现lncRNA内含子中重要的顺式作用元件，阐明一些重要lncRNA表达的剪接机制及其多种选择性剪接产物的功能差异性，从而有利于进一步理解lncRNA的功能及其在基因表达与发育、代谢中的调控作用。

RNA剪接是转录后加工与基因表达调控的关键步骤，本项目以果蝇与人类的长非编码RNA（lncRNA） 中内含子元件和选择性剪接为研究对象，先后采用生物信息学，RNA分子生物学和果蝇基因组编辑等多种技术，开展分析了果蝇与人类lncRNA的相关研究。首先，我们比对分析了长非编码RNA与编码基因的基本剪接元件，发现它们在序列上总体差异不显著。但是在5’与3’剪接位点强度上，长非编码RNA内含子比编码RNA内含子的显著偏低。其次，我们系统分析了果蝇属昆虫lncRNA内含子的保守性，获得和建立了325个lncRNA内含子中除剪接基本元件外的保守元件数据库。最后深入研究了果蝇lncRNA rox2，揭示出其特异性选择性剪接受到性别决定因子Sxl的调控。因此，本项目研究结果揭示出非编码与编码基因内含子的基本剪接元件存在的相同点与差异性；建立和提供了果蝇属昆虫保守lncRNA内含子中的潜在顺式作用元件；阐明了rox2这一lncRNA的性别特异性选择性剪接的调控机制。本项目的执行对进一步深入理解lncRNA的生物学功能，其在基因表达和发育代谢中的调控机制具有重要的理论意义。