How short-ranged electrostatics controls the chromatin structure on much larger scales

Helmut Schiessel

doi:10.1209/epl/i2002-00616-4

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arXiv · cond-mat/0110032

How short-ranged electrostatics controls the chromatin structure on much larger scales

Helmut Schiessel

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Abstract

We propose that the degree of sweeling of the 30nm chromatin fiber (a "measure" of its transcriptional activity) is mainly determined by the short-ranged electrostatical interaction between different sections of the "folded" DNA chain. These sections constitute only a small fraction of the chain and they are located close to the entry-exit points of the DNA chain at the nucleosome core particles. We present a model that allows to estimate the degree of swelling of chromatin fibers as a function of salt concentration, charge density of the strands etc. Different mechanisms by which the state of chromatin can be controlled in vitro and in vivo are discussed.

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Helmut Schiessel. 2001-10-01. How short-ranged electrostatics controls the chromatin structure on much larger scales. https://doi.org/10.1209/epl%2Fi2002-00616-4

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