化学因素对基于DNA折纸界面上的核酸适配体与凝血酶相互作用影响的研究  

Chemical factors on the binding reaction of thrombin and aptamer based on DNA origami interface

作　　者：樊友杰[1] 吴娜[2,3] 李宾[2] 

机构地区：[1]宁波大学物理系,浙江宁波315211 [2]中国科学院上海应用物理研究所,物理生物学研究室,上海201800 [3]中国科学院大学,北京100049

出　　处：《电子显微学报》2013年第2期144-149,共6页Journal of Chinese Electron Microscopy Society

基　　金：国家科技部973项目(No.2012CB932600;No.2013CB932801);国家自然科学基金资助项目(No.21073222;No.11074137);中国科学院知识创新工程重要方向资助项目(No.KJCX2-EW-N03)

摘　　要：核酸适配体(aptamer)与DNA折纸都是由DNA分子折叠而成,两者具有得天独厚的相似性与相容性。本文将aptamer修饰在DNA折纸界面预先设定的位置上,通过原子力显微镜成像手段,在单分子水平上研究了化学因素对DNA折纸界面上的aptamer与凝血酶(thrombin)反应的影响。实验结果表明:修饰固定在DNA折纸界面上的aptamer与thrombin间的结合能力与缓冲液、某些金属离子及其浓度相关,发现HEPES缓冲液是一种比较适合基于DNA折纸的aptamer与thrombin反应的化学反应环境,在此缓冲体系中加入一定浓度的Mg2+和K+是保持反应体系稳定性及其DNA空间构型的有效途径。该研究结果有助于加深对aptamer的三维结构以及与靶分子间的对应识别关系的理解,对DNA折纸与aptamer在生物分子识别的研究和应用方面将起到一定的借鉴作用。Aptamer and DNA origami have the unique similarity and compatibility due to folding both by DNA molecules.With atomic force microscopy,we studied the chemical factors that affect the binding reaction of thrombin with aptamer which designed on DNA origami at the single molecular level.Results show that the binding ability of thrombin with aptamer fixed on the interface of DNA origami is obviously affected by the chemical factors including the buffers,metal ions,and ionic strength.We find that HEPES buffer containing a certain concentrations of Mg2＋ and K＋ is essential to keep the DNA origami stable and induce aptamers forming effective spatial configurations that recognize and bind its partner-thrombin,thus it is one kind of suitable chemical reaction environments for the aptamer-thrombin binding reaction happening on the interface of DNA origami.This study is useful to our understanding the relationship between the three-dimensional structure of aptamers and its specific recognition capability for its target molecule based on the interface of DNA origami.

关 键 词：原子力显微镜 DNA折纸 核酸适配体 凝血酶 化学因素 

分 类 号：Q52[生物学—生物化学] Q75