Histone H4 (Tyr-72), Phosphospecific Antibody

Chromatin structure is regulated through the activity of core histones (H2A, H2B, H3, and H4) that form the nucleosome. Histone activity is regulated by a variety of post-translational modifications, including acetylation, phosphorylation, and methylation. Histone acetylation and methylation occur primarily at lysine (K) residues in the amino-terminal tail domain. These modifications are important for the regulation of histone deposition, transcriptional activation, DNA replication and repair. Acetylation and methylation of specific lysine residues creates docking sites for DNA repair, transcription, and chromatin regulatory proteins. Methylation of histones may be regulated by phosphorylation events at sites downstream of the N-terminal tail. In histone H4, both EGFR activation and inonizing radiation induce EGFR nuclear translocation and Histone H4 (Tyr-72) phosphorylation, which creates a docking site for Set8 methyltransferase. This promotes K20 methylation in Histone H4 leading to DNA synthesis and repair.

The antibody was cross adsorbed to unphosphorylated histone H4 (Tyr-72) peptide before affinity purification using phospho-histone H4 (Tyr-72) peptide. This antibody antibody detects a 10 kDa* protein on SDS-PAGE immunoblots of human PC3 and A431 cells. This reactivity is not observed after alkaline phosphatase dephosphorylation of histone H4. This site is well conserved in rat and mouse histone H4, but the site is not found in other histone family members.