FIGURE 6:

PRA and PRB interact with FAK complexes and regulate their turnover. (A) MDA-iPRAB cells were induced by RSL1 and/or Dox for 24 h and then exposed to 10^–8 M R5020 or vehicle for 1 h. Cell lysates were incubated with either total FAK antibody or nonrelated antibody (immunoglobulin G). Lysates (input) and immunoprecipitates (IPs) were analyzed by Western blot for FAK^Y397P, FAK^total, PRA, PRB, and tubulin. Framed inset: the coIP experiments were repeated using iPRAB cells induced by either Dox or RSL1 + Dox to induce PRB or PRA + PRB for 24 h. (B) iPRAB cells were induced by either RSL1 or Dox or both of them and then treated or not by 10⁻⁸ M R5020 for 10 h. Western blots were performed and quantified as described in Figure 4A for FAK^Y397P, FAK^total, PRA, PRB, and tubulin (mean ± SEM, Mann–Whitney statistical test). (C) Ishikawa cells stably transfected by either PRA or PRB and T47D cells endogenously expressing PRA and PRB were treated either by 10⁻⁸ M R5020 or vehicle for 24 h. Western blot analyses were performed as in B.