DOT1介导的H3K79甲基化修饰的调节机制

项目名称： DOT1介导的H3K79甲基化修饰的调节机制

项目编号： No.31471206

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 生物科学

项目作者： Man Mohan

作者单位： 上海交通大学

项目金额： 90万元

中文摘要： DOT1是一个高度保守的组蛋白H3第79位赖氨酸（H3K79）的甲基转移酶。DOT1和H3K79甲基化跟基因转录调控相关，在MLL融合基因导致的白血病中起关键作用。本项目中，我们计划研究DOT1介导的H3K79甲基化的分子调控机制，及其磷酸化修饰是否调节甲基转移酶活性。首先，我们将纯化和鉴定DOT1相互作用蛋白及其复合物,运用ChIP-seq以及RNA-seq的方法鉴定这些复合物的靶基因，并研究它们在基因转录调控中的作用。为了研究DOT1磷酸化是否调控其酶活性，我们将突变DOT1上的磷酸化位点并检测突变体的活性。我们将进一步筛选DOT1的激酶，研究DOT1的磷酸化及其激酶在DOT1所介导的功能中的作用，包括基因转录调控，Wnt和STAT信号通路，以及细胞周期调控等。本项目将揭示DOT1介导的H3K79甲基化的新的分子调节机制，为白血病的诊断治疗提供新的理论模型。

中文关键词： H3K79；甲基化；表观遗传学；白血病；DOT1L；转录

英文摘要： DOT1 is a highly conserved Histone Methyltransferase (HMTases) capable of methylating lysine 79 of Histone H3 (H3K79). DOT1 and H3K79 methylation are associated with transcriptional regulation, and this function is proposed to play a crucial role in Mixed Lineage Leukemia (MLL) translocation based leukemic pathogenesis. Therefore it is crucial to understand the molecular mechanism of generation and regulation of H3K79 methylation. We will employ two strategies towards this goal - 1) purification and characterization of interaction partners of DOT1 and define various DOT1 complexes. Using combined approach of biochemical assays and ChIP-seq and RNA-seq technologies, how these protein complexes and interaction partners regulate H3K79 methylation and gene transcription will be investigated. 2) As phosphorylation of DOT1 might regulate its H3K79 methylase activity, we will analyze the function of phosphorylated residues by in vitro histone methyltransferase assay. To understand the biological function of various DOT1 complexes and interaction partners, and phosphorylated DOT1, we will analyze their roles in DOT1 mediated function including gene transcription, Wnt and STAT signaling pathways, and cell cycle. These studies will help us understand the mechanisms of regulation of H3K79 methylation by DOT1 and how mis-regulation of these mechanisms may lead to leukemogenesis.

英文关键词： H3K79 Methylation;Epigenetics;Leukemia;DOT1L;Transcription