Figure 4

Connexin43 and PKCδ are present in a protein complex. (A). Whole cell extracts from cells treated with vehicle or 5 ng/ml FGF2 for 15 minutes were subjected to western blotting with the indicated antibodies (n = 3). (B). Whole cell extracts were immunoprecipitated (IP) with non-immune IgG, anti-PKC (δ, pan or ε) or anti-Cx43 antibodies, as indicated. The supernatant (S) and bead (B) fractions from the immunoprecipitations were subjected to western blotting (WB) with anti-PKC (δ, pan or ε) antibodies. Immunoprecipitation with anti-Cx43 antibodies co-precipitates PKCδ (as well as PKCε). (C). Whole cell extracts were immunoprecipitated with non-immune IgG, anti-Cx43, or anti-PKC (pan, δ, or ε) antibodies, as indicated. The supernatant (S) and bead (B) fractions from the immunoprecipitations were subjected to western blotting with Cx43 antibodies. All three anti-PKC antibodies co-precipitate Cx43. (D). Whole cell extracts were prepared from cells treated with 5 ng/ml FGF2 for 10 minutes. The extracts were immunoprecipitated with non-immune IgG, anti-Cx43, or anti-phospho-PKCδ (Thr505) antibodies, as indicated. The bead fractions from the immunoprecipitations were subjected to western blotting with anti-Cx43 or anti-phospho-serine antibodies. Anti-phospho-PKCδ (Thr505) antibodies preferentially co-immunoprecipitate serine phosphorylated Cx43.