Specifically, I would like to know how histone modifications that are associated with changes in gene expression, change the flexibility of the chromatin fiber. For an example, does H3K27ac make the chromatin more flexible, and by how much?
Specific references would be appreciated because I can not find them.
I am not sure i understand the question but depending on the physichochemical characteristics that the chemical groups modifying histones introduce to the polymer could either lower or higher the persistence length of it, i think that the above in combination with structural characteristics of the fiber region that define protein interactions near genes and nuclear molecular consistency drive the persistence length of a chromatin fiber
Great question, not many studies have addressed this issue. Look at some excellent computational modeling of this issue (e.g Garyk Papoain's lab), and sedimentation experiments by Jeff Hansen's lab.
Although oversimplifying things lacks accuracy maybe the negativity of acetyl groups repulse the negatively charged dna backbone away from the histonic octamer and thus creating a less compacted nucleosome
- Badges
- Science topic
- Similar topics
- Phytochemistry
- Extracts