Prader-Willi综合征区域长非编码RNA sno-lncRNAs的分子功能机制

长非编码RNA一般指长度大于200个核苷酸、不具编码蛋白质能力的长链RNA分子。它们广泛参与调控细胞的重要功能，并与一些人类重大疾病相关。我们前期研究发现一类内含子来源的两端以snoRNAs结尾的长非编码RNA，命名为sno-lncRNAs。其中5个来源于Prader-Willi综合征（PWS）区域，在PWS病人中表达缺失。该区域sno-lncRNAs在正常人源胚胎干细胞中高表达，富集并形成稳定的细胞核亚结构；其产生依赖于snoRNP复合物，并参与剪接调控因子Fox介导的可变剪接。然而这些新分子在体内的作用靶标，及其表达缺失与PWS疾病的关系仍不清楚。本申请项目拟采用RNA反义核酸纯化方法（RAP）精确研究与PWS区域sno-lncRNAs相互作用的多种生物大分子（包括蛋白质、RNA和DNA），通过多种实验和计算方法建立sno-lncRNAs的分子功能模型，为PWS致病机理研究拓展新方向。

Long noncoding RNAs (lncRNAs) are non-protein-coding RNAs longer than 200 nucleotides, many of which play important roles in biological processes and are associated with a number of human diseases. We have reported a class of intron-derived lncRNAs named sno-lncRNAs, and five of them are absent in human genetic disorder Prader-Willi Syndrome (PWS). These PWS-region-associated sno-lncRNAs are highly expressed in human embryonic stem cells (hESCs), enriched in nucleus with sub-nuclear localization, and involved in Fox-regulated alternative splicing. However, whether other molecular partners (such as proteins, RNA and DNA) are also involved in functions of those sno-lncRNAs and how they perform in hESCs remain unclear. The relationship between lack of expression of those sno-lncRNAs and PWS disease is also unknown. In this proposal, we will employ a recently-developed technology, RNA Antisense Purification (RAP), to perform a high-throughput survey of proteins, RNA and chromatin DNA that interact with those sno-lncRNAs in hESCs. Sno-lncRNAs-centric interactome will be resolved with comprehensive experimental validation using iCLIP, Hi-C and combined bioinformatic analysis. Together, these proposed studies will illustrate the molecular basis of PWS-region-associated sno-lncRNAs, and also provide new insights into PWS pathogenesis.