Effects of Ionic Dependence of DNA Persistence Length on the DNA Condensation at Room Temperature  

作　　者：毛伟 刘艳辉 胡林 许厚强 

机构地区：[1]College of Science, Guizhou University [2]Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region Ministry of Education, College of Animal Science, Guizhou University [3]State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences

出　　处：《Communications in Theoretical Physics》2016年第5期639-644,共6页理论物理通讯（英文版）

基　　金：Supported by National Natural Science Foundation of China under Grant Nos.11047022,11204045,11464004 and 31360215;The Research Foundation from Ministry of Education of China(212152);Guizhou Provincial Tracking Key Program of Social Development(SY20123089;SZ20113069);The General Financial Grant from the China Postdoctoral Science Foundation(2014M562341);The Research Foundation for Young University Teachers from Guizhou University(201311);The West Light Foundation(2015)and College Innovation Talent Team of Guizhou Province,(2014)32

摘　　要：DNA persistence length is a key parameter for quantitative interpretation of the conformational properties of DNA and related to the bending rigidity of DNA.A series of experiments pointed out that,in the DNA condensation process by multivalent cations,the condensed DNA takes elongated coil or compact globule states and the population of the compact globule states increases with an increase in ionic concentration.At the same time,single molecule experiments carried out in solution with multivalent cations(such as spermidine,spermine)indicated that DNA persistence length strongly depends on the ionic concentration.In order to revolve the effects of ionic concentration dependence of persistence length on DNA condensation,a model including the ionic concentration dependence of persistence length and strong correlation of multivalent cation on DNA is provided.The autocorrelation function of the tangent vectors is found as an effective way to detect the ionic concentration dependence of toroidal conformations.With an increase in ion concentration,the first periodic oscillation contained in the autocorrelation function shifts,the number of segment contained in the first periodic oscillation decreases gradually.According to the experiments,the average long-axis length is defined to estimate the ionic concentration dependence of condensation process further.The relation between long-axis length and ionic concentration matches the experimental results qualitatively.

关 键 词：DNA condensation Monte Carlo simulation persistence length multivalent cation 

分 类 号：Q52[生物学—生物化学]