DDRGK1 regulates the stability of IκBα.

<p>(A) Effect of down-regulation of DDRGK1 on the NF-κB family protein expression. U2OS cells were transiently transfected with mixed DDRGK1 siRNAs or a control siRNA. 48 hours after transfection, cell lysates were prepared and subjected to immunoblot analysis of NF-κB-related protein expression (p50, p65, IKKα, IKKβ, IKKγ, IκBα). The β-actin was used as a loading control. (B) DDRGK1 regulates the stability of IκBα. U2OS cells were transfected with mixed DDRGK1 siRNAs or a control siRNA. 48 hours after transfection, cells were treated with 10 ng/ml TNF-α at indicated time. The cell lysates were prepared and subjected to immunoblotting analysis of IκBα expression. (C) DDRGK1 regulates the phosphorylation of IκBα. U2OS cells were transfected with mixed DDRGK1 siRNAs or a control siRNA. 48 hours after transfection, cells were treated with 10 ng/ml TNF-α at indicated time in the presence of 20 µM MG132. The cell lysates were subjected to immunoblotting analysis with the phospho-IκBα antibody. β-actin was used as a loading control.