噬菌体phiC31整合酶在牛基因组中介导基因定点整合的分子机制研究

项目名称： 噬菌体phiC31整合酶在牛基因组中介导基因定点整合的分子机制研究

项目编号： No.31301009

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： 曲立娟

作者单位： 上海市第八人民医院

项目金额： 25万元

中文摘要： 噬菌体phiC31整合酶介导外源基因在基因组中的特异性整合是转基因生物和基因治疗领域最有希望的方法之一，但其在真核细胞中介导定点整合的机制研究还不深入。我们在前期工作中首次鉴定了牛基因组中32个整合酶位点，发现DNA序列可能是整合酶发挥定点整合作用的重要影响因素。本研究拟在此基础上构建表达phiC31整合酶的牛细胞株，通过染色质免疫共沉淀-测序技术分析phiC31整合酶在基因组范围内识别结合的DNA序列；运用生物信息学方法分析其作用位点及旁侧序列的序列特征；通过研究组蛋白乙酰化状态改变对整合酶识别位点的影响，来探讨表观修饰在引导整合酶对位点特异性识别上所发挥的作用。本项目首次在全基因组范围、从序列特征和表观修饰两方面来研究整合酶在牛基因组中介导定点整合的机制，这些研究将为加快phiC31整合酶在基因工程中的应用、为提高转基因操作和基因治疗的安全性有和效性提供理论支持。

中文关键词： phiC31整合酶；结合位点；染色质免疫共沉淀-测序；；

英文摘要： The Streptomyces phage phiC31 integrase can effectively integrate attB-containing transgenes directly into mammalian genomes at endogenous pseudo attP sites. It is a potential tool for both gene therapy and generation of transgenic animals,however,the mechanism of site-specific integration is not clear. In our previous study, 32 integration sites were found in bovine genome for the first time and by analyzing the DNA sequences of pseudo attP sites, we found that DNA sequence recognition might play an important role in guiding phiC31-mediated site-specific integration. In this study, we will establish a bovine cell line stably expressing phiC31 integrase protein, use chromatin immunoprecipitation- sequencing(ChIP-seq) method to find the DNA sequences phiC31 integrase binding, analyze the sequence characters of pseudo attP sites and the sequence around them by bioinformatics methods. We will also analyze the influence of histone acetylation on site-specific integration by phiC31 integrase,in order to find if the epigenetic modification plays a role in regulating the function of this integrase in bovine genome. In this project, we study the action characters of phiC31 integrase on the genome scale for the first time, analyze the mechanism of this system from the aspects of sequence recognition and epigenetic modifi

英文关键词： phiC31 integrase；binding sites；ChIP-Sequencing；；