Class I histone deacetylase (HDAC (specifically HDAC1, HDAC2, HDAC3, HDAC8 as the class I members))

Class I histone deacetylase refers to a subgroup of the histone deacetylase family consisting of HDAC1, HDAC2, HDAC3, and HDAC8 in humans. These zinc-dependent enzymes are primarily nuclear and are responsible for removing acetyl groups from lysine residues on the N-terminal tails of core histones, thereby promoting chromatin condensation and repression of gene transcription[2][3][7]. They also act on non-histone proteins to regulate protein function, stability, and interactions[5]. Class I HDACs serve as core catalytic components of large multiprotein complexes involved in key cellular processes such as gene expression regulation, cell cycle progression, differentiation, and apoptosis[2][3][5]. Deregulation of class I HDACs is implicated in the pathogenesis of various diseases, notably cancer, neurodegenerative conditions, and some psychiatric disorders[5][6]. Multiple approved and investigational drugs target these enzymes to modulate epigenetic states in cancer and other diseases, most often via inhibition of deacetylase activity[6].

Other names

HDAC1HDAC2HDAC3HDAC8Rpd3-like histone deacetylase (homology-based)Lysine deacetylase (alternate enzyme family name)

Inhibition of deacetylase activity (leading to increased acetylation), Modulation of chromatin accessibility (leading to activation or repression of target genes), Induction of cell cycle arrest or apoptosis (in cancer therapy), Resensitization to other chemotherapeutic agents