Correlated and Decorrelated Positional and Orientational Order in the Nucleosomal Core Particle Mesophases

TL;DR

This paper studies how nucleosomal core particles organize in dense phases, revealing complex orientational and positional orderings and proposing scenarios for phase transitions from hexagonal to lamellar structures.

Contribution

It introduces a detailed analysis of the coupling between orientational and positional order in nucleosomal mesophases and suggests mechanisms for phase transitions.

Findings

Inhomogeneous polar ordering leads to 2D crystallization.

Different orientations of polarization vectors are observed within the unit cell.

Proposed scenarios explain transitions from hexagonal to lamellar phases.

Abstract

We investigate the orientational order of transverse polarization vectors of long columns of nucleosomal core particles and their coupling to positional order in high density mesophases discovered recently. Inhomogeneous polar ordering of these columns precipitates crystalization of the 2D sections with different orientations of the transverse polarization vector on each column in the unit cell. We propose possible scenarios for going from the 2D hexagonal phase into distorted lamellar and related phases observed experimentally.