histone acetyltransferase

biology

Also known as: HAT

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Last updated

July 22, 2026

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Histone acetyltransferases (HATs) are enzymes that play a crucial role in regulating gene expression through a process called epigenetic regulation. They function by adding acetyl groups to histones, which are proteins that package and organize DNA within the cell's nucleus. This acetylation process generally leads to the activation of genes, making the DNA more accessible for transcription.12

Histones, along with DNA, form nucleosomes, the basic structural units of chromatin. The chemical modifications on histones, such as acetylation by HATs or methylation, can either activate or repress gene expression without altering the underlying DNA sequence. This mechanism is vital for controlling cellular processes and development.12

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histone
…act on histones, such as histone acetyltransferases (HATs), which add acetyl groups and promote gene activation, and histone deacetylases (HDACs), which remove acetyl groups and generally block gene activity.
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…act on histones, such as histone acetyltransferases (HATs), which add acetyl groups and promote gene activation, and histone deacetylases (HDACs), which remove acetyl groups and generally block gene activity.
Read More