Journal
MOLECULAR CELL
Volume 27, Issue 1, Pages 135-147Publisher
CELL PRESS
DOI: 10.1016/j.molcel.2007.05.037
Keywords
-
Categories
Ask authors/readers for more resources
Using magnetic tweezers to investigate the mechanical response of single chromatin fibers, we show that fibers submitted to large positive torsion transiently trap positive turns at a rate of one turn per nucleosome. A comparison with the response of fibers of tetrasomes (the [H3-H4](2) tetramer bound with similar to 50 bp of DNA) obtained by depletion of H2A-H2B dimers suggests that the trapping reflects a nucleosome chiral transition to a metastable form built on the previously documented right-handed tetrasome. In view of its low energy, < 8 kT, we propose that this transition is physiologically relevant and serves to break the docking of the dimers on the tetramer that in the absence of other factors exerts a strong block against elongation of transcription by the main RNA polymerase.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available