Physics – Condensed Matter – Soft Condensed Matter
Scientific paper
2001-04-25
Physical Review E (1 november 2001)
Physics
Condensed Matter
Soft Condensed Matter
38 pages 15 figures
Scientific paper
This paper focuses on mechanical aspects of chromatin biological functioning. Within a basic geometric modeling of the chromatin assembly, we give for the first time the complete set of elastic constants (twist and bend persistence lengths, stretch modulus and twist-stretch coupling constant) of the so-called 30-nm chromatin fiber, in terms of DNA elastic properties and geometric properties of the fiber assembly. The computation naturally embeds the fiber within a current analytical model known as the ``extensible worm-like rope'', allowing a straightforward prediction of the force-extension curves. We show that these elastic constants are strongly sensitive to the linker length, up to 1 bp, or equivalently to its twist, and might locally reach very low values, yielding a highly flexible and extensible domain in the fiber. In particular, the twist-stretch coupling constant, reflecting the chirality of the chromatin fiber, exhibits steep variations and sign changes when the linker length is varied. We argue that this tunable elasticity might be a key feature for chromatin function, for instance in the initiation and regulation of transcription.
Ben-Haim Eli
Lesne Annick
Victor Jean-Marc
No associations
LandOfFree
Chromatin: a tunable spring at work inside chromosomes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Chromatin: a tunable spring at work inside chromosomes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chromatin: a tunable spring at work inside chromosomes will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-647820