histone deacetylase

Histone deacetylases (HDACs) are enzymes that play a crucial role in regulating gene expression through epigenetic mechanisms. They function by removing acetyl groups from histones, which are proteins that package DNA within the cell nucleus. This deacetylation process generally leads to the repression of gene activity.12

Histones, composed of basic amino acids like lysine and arginine, combine with DNA to form nucleosomes, the fundamental units of chromatin. This packaging allows the long DNA molecules to fit within the nucleus and influences the accessibility of DNA to transcription machinery, thereby controlling gene expression. Modifications to histones, including acetylation and methylation, are key to epigenetic regulation, altering gene activity without changing the DNA sequence itself.21