Figure 4

Determination of the localization and interaction of molecular markers in vitro . FETα and FETα-DN cells were grown to 80% confluence followed by growth factor deprivation for 48 h. (A) Subcellular fractionation to separate cytosolic from mitochondrial fractions was performed on FETα and FETα-DN cells followed by western blot analysis probing for XIAP and survivin. Hsp70 and porin proteins were used as compartmentalization controls for cytosol and mitochondria, respectively; or (B) Differences in survivin/XIAP complex formation were determined by immunoprecipitation with XIAP mouse monoclonal antibody followed by western blot analysis was performed for survivin.