Fig. 3. Western blots of cell lysates and immunoprecipitates (IP). Interaction of TC48 with p23 and p25 in mammalian cells. Cos-1 cells were co-transfected with GFP-TC48 and myc-p25 (A), or GFP-TC48 and myc-p23 (B) expression constructs. After 36 hours of transfection, cell lysates were prepared and immunoprecipitation with anti-myc or control antibody was performed as described in Materials and Methods. Input is 5% of the total cell lysate; IgG(H) is the band generated by the heavy chain of antibodies used for immunoprecipitation. G11 is the mouse monoclonal antibody that recognizes overexpressed TCPTP. (C) Cos-1 cells were transfected with GFP-TC48 and, after 36 hours, cell lysates were subjected to immunoprecipitation with control antibody (C) or antisera that recognize native p23 or p25 proteins. Western blot of immunoprecipitates was done with GFP monoclonal antibody. Lysates from untransfected cells were also used as controls for immunoprecipitation.