Histone H3 and Histone H4 (H3 and H4)

Histone H3 and Histone H4 are highly conserved nuclear proteins fundamental to eukaryotic chromatin structure. Together with histones H2A and H2B, they form the nucleosome core around which DNA is wrapped, enabling efficient DNA packaging and contributing to chromatin architecture. Both H3 and H4 possess N-terminal tails that undergo extensive post-translational modifications—including acetylation, methylation, phosphorylation, and ubiquitination—that regulate gene transcription, DNA replication, DNA repair, and chromosome stability by altering chromatin accessibility. These modifications serve as “epigenetic marks” linked to cellular differentiation, development, and disease processes. Dysregulation or mutation of histone H3 or H4 or their modifying enzymes is implicated in various cancers, developmental syndromes, and neurodegenerative diseases. Targeting histone-modifying processes is an established therapeutic strategy, with several approved drugs that act as inhibitors of histone deacetylases and methyltransferases, affecting the function of H3 and H4 within the chromatin context[2][4][5][6][8].

Other names

Core histones H3 and H4H3 histone familyH4 histone familyHistone cluster proteins (various gene-based aliases: HIST1H4A, HIST1H3A, etc.)

Inhibition of histone deacetylation (leads to increased acetylation and gene expression) Inhibition of histone methylation (impacts chromatin state and transcription) Modulation of nucleosome dynamics and chromatin accessibility