G-四链体DNA与石房蛤毒素相互作用机理研究

项目名称： G-四链体DNA与石房蛤毒素相互作用机理研究

项目编号： No.21504021

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 郑斌

作者单位： 合肥师范学院

项目金额： 21万元

中文摘要： 石房蛤毒素（saxitoxin，STX）对DNA的G-四链体结构形成的阻碍作用可作为构建基于DNA的检测STX传感体系的重要手段，然而，STX与G-四链体之间的相互作用机理尚需探讨。本项目拟选取具有不同强度和层数的G-四链体与STX作为研究对象，通过圆二色谱研究STX对G-四链体形成过程构象转变的影响；利用等温滴定微量热法和驻留分光光度计研究STX对G-四链体形成过程热力学和动力学的影响，探究结合反应级数、相互作用Gibbs自由能、作用位点数等；利用核磁共振和电喷雾质谱进行作用位点研究，并探讨STX与G-四链体相互作用机理。利用STX对G-四链体构象转变的影响规律，设计针对STX检测的DNA识别元件。通过此项研究，不仅可以探究富含鸟嘌呤的DNA序列与STX之间的相互作用机理，亦可对检测STX的传感体系的设计提供理论基础。

中文关键词： G-四链体；石房蛤毒素；相互作用；机理

英文摘要： The inhibition effect of saxitoxin (STX) on G-quadruplex DNA formation can be utilized for the construction of DNA based STX detection system. However, the interaction mechanism between STX and G-qudruplex DNA is not clear. Therefore, in this project, we prepare to study the interaction between STX and G-quadruplex DNAs with different strengths and layers. The conformational switches are monitored by circular dichroism spectroscopy (CD). The thermodynamics and kinetics are studied by isothermal titration calorimetry (ITC) and stop-flow spectroscopy to deduce the order of reaction, Gibbs free energy and interaction site numbers. The interaction sites are inspected through nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS) to explore the interaction mechanism. Through the above studies, we mean to obtain the influence rule of STX on G-quadruplex conformation and design DNA sequence as STX recognition element in future sensor preparation. In all, our project will not only explore the interaction mechanism between STX and DNA sequences rich in guanine bases but also will lay foundations for STX sensing system construction.

英文关键词： G-quadruplex;saxitoxin;interaction;mechanism