Representative blot from a previous lot. HeLa acid extracts were resolved by electrophoresis, transferred to nitrocellulose and probed with H5110-17H H4 (1:2000) (Lane 1) or pre-absorbed with 1uM Histone H4 peptides with the following modifications: Lane 2: monomethyl-lysine 20 Lane 3: dimethyl-lysine 20 Lane 4: trimethyl-lysine 20 Proteins were visualized using a goat anti-rabbit secondary antibody conjugated to HRP and a chemiluminescence detection system. Arrow indicates trimethyl- Histone H4 (Lys20), (10kD).