FIG. 3.

Mapping of residues involved in plakoglobin phosphorylation by Src, Fer, and Fyn kinases. Five picomoles of GST-plakoglobin deletion mutants (A) or the indicated point mutants (B) was phosphorylated with either 0.5 U of recombinant Src (upper panel), Fer kinase purified from transfected RWP1 cells (middle panel), or Fyn kinase immunoprecipitated from transfected RWP1 cells (lower panel) as described in Materials and Methods. Samples were analyzed by Western blotting (WB) with anti-PTyr MAb and reblotted with anti-GST (A) or anti-plakoglobin (B) to ensure that similar levels of GST-plakoglobin forms were present in all cases. +, present; −, absent.