Chromatin fibers stabilize nucleosomes under torsional stress

Abstract

Torsional stress is generated during DNA replication and transcription, however, the propagation of twist in condensed chromatin is poorly understood. Here the authors measure how force and torque impact chromatin fibers and find that the fibers fold into a left-handed superhelix that can be stabilized by positive torsion, suggesting that chromatin fibers stabilize nucleosomes under torsional stress.