硫氧还蛋白识别其蛋白质底物的结构生物学基础和通用规律

项目名称： 硫氧还蛋白识别其蛋白质底物的结构生物学基础和通用规律

项目编号： No.30870490

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 生物科学

项目作者： 周丛照

作者单位： 中国科学技术大学

项目金额： 32万元

中文摘要： 硫氧还蛋白系统是原核和真核生物中最普遍和最重要的氧化还原系统，它通过控制各种不同的蛋白质底物的氧化还原状态而参与大量的生物学过程。然而，现在并不清楚这些结构高度保守的小分子量蛋白是如何识别三维结构和生物学功能各不相同的底物蛋白，并实现有效的电子传递。我们以酿酒酵母这一最经典的真核模式生物为研究对象，以X射线晶体衍射的方法为手段，系统表达和纯化了硫氧还蛋白的一批底物蛋白，解析了一组具有代表性的底物蛋白及其与硫氧还蛋白复合物的晶体结构。结合定点突变、活性分析和计算机预测等手段揭示了硫氧还蛋白识别其底物蛋白的结构生物学基础和通用规律。这将有助于我们设计并优化可以阻断二者相互识别的化学小分子，用于氧化应激相关疾病的治疗。

中文关键词： 硫氧还蛋白；晶体结构；蛋白质复合物；相互作用界面；酿酒酵母

英文摘要： Thioredoxin system is the most ubiquitous and important redox system in prokaryotes and eukaryotes. It involves in many biological processes through modulating the redox states of the protein substrates. However, it is unclear how the thioredoxin that has a highly conserved structure and low molecular weight recognizes the protein substrates of distinct structures and functions, and then transfer electrons successfully. Here, we systematically prepared a series of protein substrates of thioredoxin from Saccharomyces cerevisiae and determined their structures as well as complex with thioredoxin using X-ray diffraction crystallography. Furthermore, we identified the functions of these proteins in combination with mutagenesis, enzymatic assays and bioinformatics prediction. These results provide insights into the structural basis and general rules of recognizing protein substrates by thioredoxin. It will help us to design and refine inhibitors which can block the recognition interfaces, and screen potential drug candidates for treatment of oxidative stress related diseases.

英文关键词： thioredoxin;crystal structure;protein complex;interface;Saccharomyces cerevisiae