When DNA is compacted by histones into 10-nm and 30-nm fibers, the DNA is unable to interact with proteins required for gene expression. Therefore, to allow for these proteins to act, the chromatin must constantly alter its structure. Which processes contribute to this dynamic activity?
A) DNA supercoiling at or around H1
B) methylation and phosphorylation of histone tails
C) hydrolysis of DNA molecules where they are wrapped around the nucleosome core
D) accessibility of heterochromatin to phosphorylating enzymes
E) nucleotide excision and reconstruction
Illustration of multidirectionality and low density of fibers in typical fascia.
Acetylation of core histones
Preload is related to the amount of blood and stretching of the ventricular myocardial fibers
Comparison of the chromatin fibers with metaphase chromosomes
Clusters of histones in nucleosomes have their N-terminal tails
Opener Chromatin fibers spilling out of a chicken erythrocyte