Brownian dynamics simulation of the interaction between DNA and histone

In all eukaryotes,DNA wraps around a histone octamer in a left-handed way,forming a stable nucleosome structure.We numerically study the interaction between DNA and histone using a Brownian dynamics simulation.The process of nucleosome formation is shown in detail.We propose a histone octamer rotation model for the process of nucleosome formation.By simulating the stretching of a nucleosome chain we obtain the force versus extension and extension versus time curves,which are found to be consistent with experimental results.The process of chirality formation of a nucleosome is studied by building up a histone octamer model with a quantitatively adjustable chirality,and the chirality is found to be strongly dependent on the chirality of the histone octamer.We also show that the nucleosome chirality may be broken at elevated temperatures.