ICP27 arginine-to-lysine mutant proteins are less stable than wild-type (WT) HSV-1 ICP27. HeLa cells were infected with WT HSV-1 KOS, ΔRGG, or the indicated ICP27 arginine-to-lysine viral mutants. The general methylation inhibitor AdOx was added 2 h after infection, and the translation inhibitor cycloheximide (CH) was added 5 h after infection to the indicated samples. Cell lysates were collected 5 h after infection, and proteins were resolved by SDS-PAGE and transferred to nitrocellulose. ICP27 and β-actin were identified by Western blot analysis using monoclonal antibodies. Densitometry analysis was used to quantify the bands, and the relative amount of ICP27 was normalized against the loading control β-actin. The amount of ICP27 present 5 h after infection was set to 100%. Plotted are the averages of three experiments. Error bars represent standard errors of the means.