GSK--3β, not GSK-3α, decreases ZNF281 in CRC cells (A and B) HCT116 cells transfected with ZNF281, GSK-3β-WT, or GSK-3α, or GSK-3β-S9A, or GSK-3β-K85M were treated with or without the GSK-3β inhibitors LiCl (20 mM). Indicated proteins were then analyzed by Western blotting. (C) The whole lysates of wild type MEF cells and GSK-3β knockout MEF cells were subjected to immunoblotting with indicated antibodies. (D) CHX (20 μM) was used to treat MEF cells and GSK-3β knockout MEF cells for the indicated times, and endogenous ZNF281 was analyzed using western blot, and the half-lives of ZNF281 were determined. (E) siRNA against GSK-3β and GSK-3α was transfected into different kinds of human cell lines, and cell lysates were then analyzed to detect endogenous ZNF281. (F) HCT116 cells were transfected with indicated plasmids and treated with or without the proteasome inhibitor MG132 (10 μM) for 10 h. Then western blotting was performed.