G4解旋酶G4R1通过解旋G4调控基因表达和在细胞增殖中的作用机制研究

项目名称： G4解旋酶G4R1通过解旋G4调控基因表达和在细胞增殖中的作用机制研究

项目编号： No.31300654

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 生物科学

项目作者： 黄伟伟

作者单位： 西北农林科技大学

项目金额： 25万元

中文摘要： 四联体（G4）是由富含鸟嘌呤的核苷酸链所形成的四链二级结构，广泛存在于基因组中，在维持基因组稳定和调控基因表达等方面具有重要作用。G4能够为特定解旋酶所解旋。在细胞中起主要G4解旋作用的解旋酶是G4R1。G4R1具有高度的G4-DNA和G4-RNA结合和解旋活性。敲除G4R1能够影响大量具有G4的基因表达，提示G4R1在调控基因表达中具有重要作用。然而对于G4R1在体内如何解旋G4和调控基因表达，及在细胞增殖中作用还尚不清楚。本研究拟从DNA，蛋白和细胞三个层面入手，通过ChIP-Seq，IP-MS和细胞学检测等技术手段，鉴别G4R1通过解旋G4所调控的靶基因；鉴定参与G4R1解旋G4的互作蛋白或修饰；检测G4R1在正常和病理细胞增殖中的作用，旨在证实G4R1通过解旋G4-DNA的基因表达调控机制和在细胞增殖中的作用,为揭示G4-DNA及G4R1在细胞中的作用机制奠定基础。

中文关键词： 四联体；G4R1；基因表达调控；蛋白互作；乳腺癌

英文摘要： G-quadruplex (G4) are four-stranded tetrad structures linked together by Hoogsteen hydrogen bonds formed between four guanines in G-rich nucleic acid sequence. G4 are widely present in the genome, and have important roles in the genome stability maintenance and gene expression regulation. Some helicases specifically bind and resolve G4-DNA, which is important for the genome metabolism. G4 resolvase 1 (G4R1)，which is responsible for the major G4-DNA resolving activity in HeLa cells, binds and unwinds G4-DNA and G4-RNA with high affinity in vitro. The Knockout of G4R1 affects the expression of many genes having G4-DNA in their promoter region. Our previous study has demonstrated that G4R1 enhances YY1 expression through resolving the G4-DNA in YY1 promoter. These studies suggested that G4R1 play important role in the regulation of gene expression based on its' G4 resolving activity. We also found that G4R1 is over-expressed in breast cancer, which suggests G4R1 may play a role in cell proliferation and tumorigenesis. However, the mechanism of G4R1 binding and resolving of G4-DNA in vivo, and its' role in gene expression regulation and cell proliferation are less studied. In this study, using ChIP-Seq, IP-MS, cell proliferation assay and other methods, we intend to work at the DNA, proteins and cells levels in orde

英文关键词： G-quadruplex；G4R1；Gene Expression Regulation；Protein interaction；Breast cancer