The effect of linker histone's nucleosome binding affinity on chromatin unfolding mechanisms.

ABSTRACT: Eukaryotic gene activation requires selective unfolding of the chromatin fiber to access the DNA for processes such as DNA transcription, replication, and repair. Mutation/modification experiments of linker histone (LH) H1 suggest the importance of dynamic mechanisms for LH binding/dissociation, but the effects on chromatin's unfolding pathway remain unclear. Here we investigate the stretching response of chromatin fibers by mesoscale modeling to complement single-molecule experiments, and present various unfolding mechanisms for fibers with different nucleosome repeat lengths (NRLs) with/without LH that are fixed to their cores or bind/unbind dynamically with different affinities. Fiber softening occurs for long compared to short NRL (due to facile stacking rearrangements), dynamic compar

SUBMITTER: Collepardo-Guevara R 

PROVIDER: S-EPMC3183807 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature