Mass spectrometric characterization of human histone H3: a bird's eye view.
The modification of H3 in asynchronous HeLa cells was profiled using Top Down Mass Spectrometry. A broad distribution of species differing by 14 Da and containing less than 3% unmodified protein was observed for all three variants. Species of up to +168 Da were observed for H3.1, and fragmentation of all species by Electron Capture Dissociation (ECD) revealed approximately 5% methylation of K4 and approximately 50% dimethylation of K9. K14 and K23 were major sites of acetylation. H3.3 was slightly hypermodified with the apex of the distribution shifted by approximately +14 Da compared to H3.1. H3.1 (50% and 15%) from colchicine-treated cells was monophosphorylated and diphosphorylated, respectively, with equivalent modification of S10 and S28.
Thomas
C Eric
CE
Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Kelleher
Neil L
NL
Mizzen
Craig A
CA
D000107:Acetylation; D000595:Amino Acid Sequence; D006367:HeLa Cells; D006657:Histones / Q000737:chemistry*; D006801:Humans; D008745:Methylation; D008969:Molecular Sequence Data; D010766:Phosphorylation; D020033:Protein Isoforms / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization
D006657:Histones; D020033:Protein Isoforms