Figure 1

Effect of PTEN on the degradation of AIB1. (A) COS-7 cells transfected with Flag-tagged AIB1 and Gfp-tagged wild-type (wt) or G129R mutant (mu) PTEN were collected 24 h after transfection and subjected to western blot analysis with the indicated antibodies. (B) COS-7 cells were transfected with Flag-tagged AIB1 and Gfp-tagged wt or mu PTEN, and then subjected to reverse-transcription PCR analysis 24 h after transfection. (C) COS-7 cells transfected with Flag-tagged AIB1 and Gfp-tagged wt or mu PTEN were treated with or without 10 μM MG132 for 8 h. The cells were then collected and subjected to western blot analysis with the indicated antibodies. (D) MCF-7 cells transfected with siPTEN or control plasmid (siLuc) were collected and subjected to western blot analysis with the indicated antibodies 24 h after transfection. (E) MCF-7 cells transfected with siPTEN or control plasmid (siLuc) were collected 24 h after transfection and subjected to reverse-transcription PCR analysis. (F) MCF-7 cells transfected with or without Gfp-tagged wt or mu PTEN were treated with 10 μg/ml cycloheximide (CHX) for different periods of time (0, 2, 4, 6, 8 h) before subjected to western blot analysis to detect the change in AIB1 protein level. The graph shows the relative intensity of the AIB1 bands at the different time points. (G) MCF-7 cells transfected with Myc-tagged Ub and Gfp-tagged wt or mu PTEN were treated with 10 μM MG132 for 8 h. The cells were collected and then subjected to immunoprecipitation with anti-IgG or -AIB1 antibody followed by western blot analysis with anti-Myc antibody.