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Histone Deacetylases (HDACs): Function, Mechanism, & Inhibition

Nucleic Acids Structure and Mapping

  1. Sibaji Sarkar,
  2. Mckenna Longacre,
  3. Nela Tatur,
  4. Sarah Heerboth,
  5. Karolina Lapinska

Published Online: 9 JAN 2014

DOI: 10.1002/9780470027318.a9365

Encyclopedia of Analytical Chemistry

Encyclopedia of Analytical Chemistry

How to Cite

Sarkar, S., Longacre, M., Tatur, N., Heerboth, S. and Lapinska, K. 2014. Histone Deacetylases (HDACs): Function, Mechanism, & Inhibition. Encyclopedia of Analytical Chemistry. 1–9.

Author Information

  1. Boston University School of Medicine, Boston, MA, USA

Publication History

  1. Published Online: 9 JAN 2014


Acetylation and deacetylation of histones provide a balance between an open conformation and a closed chromatin conformation for the regulation of transcription. This regulation is complex, but is principally regulated by histone acetylases (HATs) and deacetylases. Histone deacetylases (HDACs) are of three classes. Class I are principally localized in the nucleus, where Class II members are localized both in nucleus and in cytoplasm. The Classes I and II HDACs, in addition to their well-known role in deacetylating histones for the inhibition of transcription also deacetylate lysine residues of other regulatory proteins to modulate their functions. Class III HDACs, which are also called sirtuins, are principally involved in metabolic processes and aging and also regulate other cellular functions. Activators of sirtuins show similar effects of low-calorie diet. Inhibitors of Classes I and II HDACs are utilized as drugs in many types of diseases including neurological disorders and cancer. Recent studies demonstrated that acetylation and deacetylation of histones regulate gene expression in coordination with other modifications such as ubiquitination, methylation, and phosphorylation. CpG island DNA methylation adds another complexity to the HDAC-mediated gene expression inhibition. It is hypothesized that regulation of proteins of similar functions could possibly be modulated by similar modifications. Elucidation of such common modifications may lead to identification of a signature, which is called histone code.