Nucleosome Switching

TL;DR

This paper analyzes nucleosome positioning along yeast DNA using statistical mechanics, revealing regions with sharp switching behavior correlated with transcription-factor binding sites, indicating a potential regulatory mechanism.

Contribution

It introduces a model showing nucleosome switching regions and their correlation with functional DNA sites, advancing understanding of chromatin organization.

Findings

Identification of nucleosome switching regions with first-order transition behavior

Strong correlation between nucleosome switches and transcription-factor binding sites

Model predicts nucleosome distribution changes with chemical potential variations

Abstract

We present a statistical-mechanical analysis of the positioning of nucleosomes along one of the chromosomes of yeast DNA as a function of the strength of the binding potential and of the chemical potential of the nucleosomes. We find a significant density of two-level nucleosome switching regions where, as a function of the chemical potential, the nucleosome distribution undergoes a "micro" first-order transition. The location of these nucleosome switches shows a strong correlation with the location of transcription-factor binding sites.