Histone deacetylases: silencers for hire

Over the past few years, the long-standing idea that covalent modification of chromatin can play a role in determining states of gene activity has bee n confirmed. Eukaryotic genes can be silenced by deacetylation of acetyllys ine moieties in the N-terminal tails of histones, Recent work links histone deacetylases with an increasing number of repressors, suggesting that deac etylation might be a rather pervasive feature of transcriptional repression systems.