Abstract
Histone post-translational modifications influence many fundamental cellular events by regulating chromatin structure and gene transcriptional activity. These modifications are highly dynamic and tightly controlled, with many enzymes devoted to the addition and removal of these modifications. Interestingly, these modifying enzymes are themselves fine-tuned and precisely regulated at the level of protein turnover by ubiquitin-proteasomal processing. Here, we focus on recent progress centered on the mechanisms regulating ubiquitination of histone modifying enzymes, including ubiquitin proteasomal degradation and the reverse process of deubiquitination. We will also discuss the potential pathophysiological significance of these processes.