Fig. 4.

STAT3 facilitates the proteasomal degradation of β-catenin. (A) HEK293T cells were transfected with wtSTAT3-myc and β-catenin-HA. After 24 h, cells were harvested. We performed an immunoprecipitation assay with an anti-HA-antibody, and Western blotting was completed with the indicated antibodies. (B) HEK293T cells were transfected with wtSTAT3-myc and β-catenin-HA and then treated with 10 μM MG132 for 10 h before harvest. After 24 h of transfection, cells were harvested. An immunoprecipitation assay was performed with an anti-HA-antibody, and Western blotting was completed with the indicated antibodies. (C) Graphical summarization. Two distinct mechanisms of β-catenin degradation by activated STAT3 is described.