The role of phosphorylation of histone H3 at serine 10 in chromatin condensation in vitro

Abstract

Post-translational modifications on histone tails play essential roles in modulating chromatin higher order structure. Phosphorylation of histone H3 at serine 10 (H3S10ph) is associated with chromosome condensation. However direct evidence and the molecular mechanism underlying chromosome condensation induced by H3S10ph in human is unclear. Herein, we employed in vitro reconstituted nucleosomal arrays mimicking H3S10ph by substitution S10 to aspartic acid (H3S10D) using human recombinant histones and highly tandem repeats widom 601 sequence. Using analytical ultracentrifugation sedimentation velocity (AUC-SV) analysis and transmission electron microscopy (TEM) observation, we found that there is no significant difference in the local folding and condensation between WT H3 and H3S10D containing nucleosomal arrays. Thus, our results suggest that H3 phosphorylation at serine 10 does not directly play a role in chromatin condensation and thus higher order structure.