FIGURE 4.

Both ΔF508 CFTR and Δ264 CFTR are associated with VCP and HDAC6 protein complex. Cos-7 cells were transfected with ΔF508 or Δ264 CFTR and treated with 10 μm MG-132 for 8 h. A, CFTR was immunoprecipitated (IP) from 500 μg of total protein and immunoblotted for VCP or HDAC6 (left panel). Protein from non-CFTR transfected Cos-7 cells was used as a negative control for CFTR immunoprecipitation, whereas total protein extracts (25 μg) were loaded as positive control (right panel). Higher amounts of both VCP and HDAC6 are coimmunoprecipitated with Δ264, as compared with ΔF508 CFTR. B, VCP or HDAC6 immunoprecipitated with ΔF508 or Δ264 CFTR for each group is shown as percentage change (mean ± S.D.) from ΔF508 protein complex. Statistics were also compared with the ΔF508 protein complex.