大分子拥挤下核酸单链的结构性质

大分子拥挤下核酸单链的结构性质 Structure Properties of Single-Stranded Nucleic Acid with Macromolecular Crowding 刘凯吉 LIU Kaiji 1 first-author 王凤华 WANG Fenghua 1 谭志杰 TAN Zhijie 1 武汉大学物理科学与技术学院 武汉大学物理科学与技术学院 School of Physics and Technology,Wuhan University School of Physics and Technology,Wuhan University 通过粗粒化模型构建核酸单链,采用Monte Carlo方法系统地研究了拥挤大分子体积比和尺寸对中性核酸单链结构性质的影响,得到了核酸单链端-端距离Ree与大分子体积比Φc和半径Rc的关系曲线.实验结果表明,大分子拥挤可导致核酸单链形成更加紧凑的结构,拥挤分子的体积分数越大、尺寸越小,核酸单链的结构越紧凑,而且大分子拥挤对较长的核酸单链影响更大,并进一步通过分析拥挤大分子的分布,揭示了大分子拥挤效应产生的机制. Nucleic acid generally resides in cellular environments with macromolecular crowding.In this work,using a coarse-grained model for single-stranded（ss）nucleic acid chain and Monte Carlo simulation,we systematically investigated the effects of volume fraction and size of crowding macromolecules on the structure properties of the ss nucleic acid chains,and obtained the relationship between the chains’ end-to-end distance Ree and the volume fractionΦc and radius Rc of crowding macromolecules.Our calculations show that the macromolecular crowding can cause a structural collapse of ss chain,which is more significant at higher volume fractionsΦc and smaller radius Rc.In addition,through analyzing the spatial distribution of crowding macromolecules,we revealed the mechanism for the effect of macromolecular crowding on nucleic acid chains. 核酸单链 Monte Carlo模拟 拥挤大分子 结构塌缩 偶分布函数 single-stranded nucleic acid Monte Carlo simulation macromolecular crowding structural collapse pair distribution function 10.14188/j.1671-8836.2014.02.004 O561 国家自然科学基金资助项目（11074191;11175132） 2014-02-01 2021-04-01 2 60