Fig. (4) Protein stability of Tip60 (wt), or N324A mutant A) GFP-Tip60 or Tip60 N324A mutant was transfected into HEK293 cells and the cells were treated with cyclohexamide. The Tip60 proteins were chased for the indicated time periods. Western blotting with a monoclonal Tip60 antibody of SDS-PAGE subjected GFP-Tip60 proteins is shown. To monitor the protein amount, an equal amount of cell lysate was subjected to western blotting with an actin antibody. Results shown are one of five repeated experiments. B) Quantification of the pulse-chase experiment is shown by image analysis with the Fuji Image Quant software.