裂殖酵母全基因组范围内研究多核糖体对于5’端不同的转录本的选择性

真核生物高度复杂的核心启动子产生了具有高度多样性的转录本5’端。这种多样性体现了真核生物转录调控的复杂性：核心启动子为了能够更为精准和动态调控基因表达而使用了多样的转录起始位点。然而，转录本的5’端多样性在转录后调控中所发挥的作用仍是一个有待研究的问题。本项目旨在利用CAGE技术并结合二代测序技术，在裂殖酵母在全基因组范围内精准捕获与多核糖体结合的转录本5’端，并通过与总RNA中的转录本5’端做定量比较，以阐明多核糖体对具有不同5’端的转录本的选择性使用，从而进一步揭示蛋白翻译对于转录起始位点和核心启动子的间接选择性。同时，本项目也将研究这种选择性与转录本5’端序列以及基因功能的相关性。总之，本项目不仅将为阐明裂殖酵母的5’端多样性在转录后调控中起到的作用提供重要的线索，也将为进一步理解高等真核生物的基因表达调控机制提供宝贵的参考信息。

The highly complex core promoters in eukaryotes generate highly diverse 5’ ends of transcripts. This diversity is one manifestation of the complex transcriptional regulation in eukaryotes: core promoters employ diverse transcription start sites to precisely and dynamically regulate gene expression. However, the role of the 5’ end diversity in post-transcriptional regulation remains unclear. In this project, we will combine the CAGE (cap analysis of gene expression) technique with next-generation sequencing to precisely capture the 5’ ends of polysome-associated transcripts on a genome-wide scale in Schizosaccharomyces pombe. By comparing the 5’ ends of polysome-associated transcripts with the 5’ ends of transcripts in total RNA, we will demonstrate the polysome selectivity toward transcripts with different 5’ ends and further reveal an indirect translational selectivity toward transcription start sites and core promoters. In addition, we will investigate the relationship between the polysome selectivity and the 5’ end sequences and gene functions. In conclusion, this project will not only provide important clues for deciphering the role of the 5’ end diversity in post-transcriptional regulation of Schizosaccharomyces pombe, but also yield useful reference for further understanding the regulatory mechanisms of gene expression in higher eukaryotes.