Figure 2.

Knockdown of CSN2 affects the basal protein level of IκBα. Cells were transiently transfected with one of two different CSN2-specific siRNAs or transfected with a nontargeting siRNA (mock). After 48 h, they were harvested by RIPA lysis. (A) Cell lysates from mock-transfected and CSN2-knockdown cells were analysed by SDS–PAGE and Western blotting. Immunodetection of CSN subunits, Cul1, IκBα, β-TrCP and ERK (see indicated panels), was performed using specific antibodies. (B) Quantification of the results shown for β-TrCP and IκBα in (A). Densitometric values for protein bands were normalised to ERK content in each sample and depicted relative to the values of untreated mock-transfected cells. The data are representative for at least three independent experiments.