Transfected hβc spontaneously associates with endogenous mβc and the βc complex is phosphorylated inappropriately in response to E21R.
Factor-deprived human UT7 cells (A) or mouse hGMR BaF-B03 cells (B-D) were stimulated as indicated for 5 minutes at 25°C. Cells were lysed and hβc was immunoprecipitated with 8E4 anti-hβc antibody (A-C). The presence of tyrosine phosphorylated hβc was detected using an antiphosphotyrosine antibody, PY20 (A) or 4G10 (B,C). Filters were then stripped and reprobed for the presence of hβc with 1C1 anti-hβc antibody (A,B). The presence of mβc following hβc immunoprecipitation was determined on a duplicate filter using anti-mβc antibody, K-17 (C). Tyrosine phosphorylated proteins were immunoprecipitated with the 4G10 antiphosphotyrosine antibody (D) and the presence of hβc detected using 1C1 antibody. The filter was then stripped and reprobed for the presence of mβc with K-17.
