Investigating Bak/Bax activating conformation change by immunoprecipitation

Activation of both Bax and Bak during apoptosis involves significant conformation change. Investigation of this phenomenon by immunoprecipitation (IP) requires a detergent such as CHAPS that does not induce significant conformation change. IP with conformation-specific Bax or Bak antibodies is observed in CHAPS only following an apoptotic stimulus, whereas the same antibodies will immunoprecipitate from both nonapoptotic and apoptotic cells in the presence of Triton X-100. Thus, the latter detergent can serve as a positive control for IP, as described here.