Fig. 7.

Bidirectional regulation of δ-catenin Ser-447 phosphorylation by neuronal activity. Hippocampal neurons (DIV23–27) were treated with bicuculline (50 μm) (A) or TTX (3 μm) (B) for the indicated times and immunoblotted with pS-447 δ-catenin phosphoantibody and for total δ-catenin (δ-cat). In C and D, SP600125 (20 μm) or MG132 (10 μm) was added 10 min prior to TTX (3 μm). Graphs at right show immunoblot intensity of Ser(P)-447 δ-catenin, total δ-catenin, and their ratio normalized to DMSO control (mean ± S.E., n = 9). *, p < 0.05; **, p < 0.01; ***, p < 0.001 (Student's t test).