Fig. 5.

In vivo inhibitory effect of Nopp140 on CK2. (A) Overexpression or knockdown of Nopp140. HeLa cells were transfected with the Nopp140 expression vector (pNopp) or siRNAs targeting Nopp140 (siNopp). For the Western blot, 20 μg of the proteins from the cleared lysates were used. (B) Negatively regulated CK2 activity by Nopp140. The cleared lysates of the HeLa cells transfected with pNopp or siNopp were incubated with α-casein. The reaction was further reacted with Kinase-Glo, and the luminescence intensity was measured using a microplate luminometer. The CK2 inhibitor DRB was used as a reference under the same conditions. All experiments were performed in triplicate. (C) Selectively regulated CK2 activity by Nopp140. The lysates of the HeLa cells treated with DRB or transfected with pNopp140 or siNopp140 were immunoblotted with phosphoserine antibodies.