The nucleosome -- a complex of 147 base-pairs of DNA with eight histone proteins -- is the fundamental unit of chromatin compaction in the living cell, which controls access to its genetic information. The exact mechanism of the control remain unclear. We analyze the DNA wrapping/unwrapping transition in the nucleosome by a simplified physical model that reveals possible general principle of the accessibility control -- alteration of the nucleosome core charge via post-translational modifications. An all-atom model confirms the basic idea, but reveals many counter-intuitive details and makes further predictions. Stability of the nucleosome complex is predicted to depend strongly on pH of the environment in the physiologically relevant range.

Nucleosome: The very special protein-DNA complex

254th National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.