Intra- and Inter-nucleosome interactions of the core histone
tail domains
Jeffrey Hayes
University of Rochester
The core histone tail domains are critical elements of chromatin structures, stabilizing wrapping of DNA within the nucleosome and directing folding of nucleosome arrays into chromatin fibers and higher order structures. We have documented a complicated array of intra- and inter-nucleosome interactions of the H3 and H4 tail domains during salt-dependent folding and oligomerization of model nucleosome arrays. We have also developed a sensitive chemical kinetics method to determine affinity of tail interactions within chromatin complexes and have studied the effect of acetylation on these interactions. We find that acetylation does not simply cause a global weakening of tail-DNA interactions within the nucleosome and that this modification overrides the effect of H1-dependent stimulation of inter-array interactions.