Figure 6. Acetylated-p27 is more stable. (A) 293 cells were treated with CHX for different time periods, cells were then lysed and IP was performed with acetylated-lysine antibody (lower). The protein half-life of acetylated-p27 (lower) was analyzed by western blot. The protein half-life of p27 was detected as control (upper). (B) The ubiquitination of acetylated-p27 was detected. After treatment with MG132, 293 cells were harvested and IP was performed with acetylated-lysine antibody, then IP with p27 antibody was performed using the elution products. The second elution products were loaded on the SDS-PAGE gel for western blot to detect the ubiquitination level of acetylated-p27.