一种尚未报导的高频率重组现象研究

项目名称： 一种尚未报导的高频率重组现象研究

项目编号： No.31272297

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 生物科学

项目作者： 马润林

作者单位： 中国科学院遗传与发育生物学研究所

项目金额： 86万元

中文摘要： 重组(Recombination)是自然界最普遍最根本的遗传现象之一，高等生物生殖细胞在减数分裂前每一对姊妹染色单体间都会发生随机交换而维持高杂合度。然而有关重组的初始动力和机制尚未在分子水平上完全阐明。我们在构建多个物种的细菌人工染色体（BAC）文库过程中观察到一种不依赖于重组酶RecA的重组现象，其频率随DNA插入片段增大而大幅提高。据此我们提出科学假设：生物中还存在着一个尚未被报道的重组机制，这种机制在选择压力下启动并替代RecA而维持重组功能。本研究拟在已成功建立BAC文库群独特实验体系基础上，系统分析并阐明在重组酶RecA缺失条件下，大肠杆菌与BAC质粒及不同物种基因组间发生高频率重组的现象和特征；进而通过基因扫描、突变、siRNA、2D电泳、酵母双杂交等技术验证这种重组发生的要素、特征和物质基础，以求最终发现替代RecA的功能蛋白或RNA。本研究可能在重组机制及其应用实现突破。

中文关键词： 上皮间质转化；TET；黑色素瘤；；

英文摘要： Genetic recombination is one of the most fundermental phenomina in nature. Animals and plants have evolved to have two arms of sister chromatins randomly exchanged for each chromosome at meosis to maintain a high level of genetic heterozygosity. However, the mechanism behand such recombination remains elucidated. We observed an abnormally high rate of recombination during the construction of bacterial artificial chromosome (BAC) libraries, and such recombinaiton is independent of recombinase RecA. We hypothesize that there exists an un-reported mechanism of recombination. We propose to investigate such phenomina utilizing the BAC libraries we have constructed for human, swine, sheep, mouse, fish, orange, triichomones and fungi. This project is aimed to analyze the phenomenon and its characteristics in different species utilizing the BAC plasmid and RecA deficient E. coli. We plan to find out the key sequences or elements, including novel protein or RNAs which could subsitute the function of RecA under certain stressed conditions. This project has a potential of making an important breakthrough in the area of basic research, expecially in recombination mechanism.

英文关键词： Epithelial Mesenchymal Transition；TET；Melanoma；；