Histone deacetylase complexes: functional entities or molecular reservoirs.

Recent investigations have allowed the identification of an increasing number of distinct nuclear multi-component complexes containing several types of enzymatic activity. Many of the complexes containing histone deacetylases are believed to control transcription and chromatin remodeling. We suggest here that at least some of these abundant complexes are likely to be "molecular reservoirs" of dynamic composition that exchange factors with other less abundant and functional complexes, according to specific required activities.