FIGURE 4.

CGN-induced increases in phospho-NIK are inhibited by BCL10 silencing. Phospho-NIK and total NIK were measured by FACE assay using antibodies for phospho-NIK (Thr⁵⁵⁹) and total NIK. A, in the MEF cells, no changes in total NIK followed CGN treatment. Following CGN, phospho-NIK increased significantly in the WT cells (p < 0.001). The CGN-induced increases in phospho-NIK were inhibited by BCL10 silencing. B, similar effects were found in the IKKα^−/− cells (p < 0.001 for phospho-NIK increase). C, in the IKKB^−/− cells, similar responses were detected (p < 0.001 for phospho-NIK increase). D, similarly, in the NCM460 cells, CGN produced an increase of ∼11% in phospho-NIK (p < 0.001). These findings demonstrate a requirement for BCL10 for the phosphorylation of NIK following CGN exposure.