Europhys. Lett.
Volume 62, Number 5, June 2003
Page(s) 753 - 759
Section Interdisciplinary physics and related areas of science and technology
Published online 01 May 2003
DOI: 10.1209/epl/i2003-00437-y
Europhys. Lett., 62 (5) , pp. 753-759 (2003)

An exact theory of histone-DNA adsorption and wrapping

Tom Chou

Department of Biomathematics and IPAM, UCLA - Los Angeles, CA 90095-1766, USA

(Received 6 January 2003; accepted in final form 27 March 2003)

We find exact solutions to a one-dimensional (1D) interacting particle theory and apply the results to the adsorption and wrapping of polymers (such as DNA) around protein particles (such as histones). Each adsorbed protein is represented by a Tonks gas particle. The length of each particle is a degree of freedom that represents the degree of DNA wrapping around each histone. Thermodynamic quantities are computed as functions of wrapping energy, adsorbed histone density, and bulk histone concentration (or chemical potential); their experimental signatures are also discussed. Histone density is found to undergo a two-stage adsorption process as a function of chemical potential, while the mean coverage by high affinity proteins exhibits a maximum as a function of the chemical potential. However, fluctuations in the coverage are concurrently maximal. Histone-histone correlation functions are also computed and exhibit rich two-length-scale behavior.

87.14.Gg - DNA, RNA.
05.20.-y - Classical statistical mechanics.
68.43.De - Statistical mechanics of adsorbates.

© EDP Sciences 2003