核酸适配体结构与动力学的非线性光谱研究

项目名称： 核酸适配体结构与动力学的非线性光谱研究

项目编号： No.21503093

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 环境科学、安全科学

项目作者： 魏锋

作者单位： 江汉大学

项目金额： 21万元

中文摘要： 核酸适配体分子的二级结构变化与动力学过程是它们实现基因调控与抗癌、抗病毒治疗的关键。本项目拟基于皮秒和频光谱系统搭建高通量多尺度的分析检测平台，对G-四链体适配体分子的结构与动力学过程进行原位实时的表征，研究适配体分子结构转变的作用机理。前期实验结果表明，适配体分子在“指纹区”包含丰富的光谱信息，可以用于适配体分子的结构分析。拟利用现有的光谱分辨和偏振分辨的和频光谱系统，对适配体分子的二级结构进行多谱段表征和手性光谱表征。发展分析方法获取适配体分子的取向信息和手性结构信息，考察溶液离子浓度、pH值、温度、磷脂电荷密度和蛋白质浓度对适配体分子结构的影响。和频振动光谱与电化学检测、表面等离子体共振等方法联用，获取适配体分子与细胞膜、蛋白质分子相互作用时的动力学特征。基于核酸适配体分子在不同条件下的结构、分子取向和动力学特征，解释适配体-细胞膜，适配体-蛋白质相互作用的分子机理和关键分子作用力。

中文关键词： 适配体；二级结构；非线性光谱；动力学过程；G-四链体

英文摘要： The secondary structure and reaction kinetics of aptamers are the keys to their functions in genetic regulation, anti-cancer therapy and anti-viral therapy. In this project, a high-throughput and multi-detection characterization platform is to be built based on the picosecond sum frequency generation spectroscopy system, to investigate the secondary structure and reaction kinetics of G-quadruplex structured aptamers. Our preliminary experimental results indicate that multiple characteristic vibrational peaks of nucleotide bases can be detected within the “finger-print” region. These spectra information can be utilized to analyze the secondary structures of aptamers. The aptamer molecules are to be investigated by wavenumber resolved and polarization resolved sum frequency generation vibrational spectroscopy (SFG-VS) via chiral sensitive detection and multi-spectra detection. The polarization analyzing methods and chiral structure analyzing methods are to be developed to gain molecular insights into the structures of aptamers at different ion concentration, pH value, termperature, lipid charge density and peptide concentration. By merging multiple characterizing techniques, such as surface plasmon resonance imaging and electrochemical detections, with SFG-VS, the kinetics of aptamers can be characterized in situ and in real time. The molecular mechanisms and driving forces of aptamer-membrane interaction, aptamer-protein interaction are also to be elucidated, based on the structures, tilt angles and kinetics of aptamers during such interactions.

英文关键词： Aptamer;Secondary structure;Nonlinear spectroscopy;Reaction kinetics;G-quadruplex