FIG 6.

CDK1 increases the CREB and c-Rel activation and enhances their binding to the miR-22 promoter. (A and B) HeLa cells were transfected with 3×FLAG-CMV-10-CDK1 or empty vector for 24 h. Fixed chromatin samples were prepared and immunoprecipitated by using antibodies specific to c-Rel and CREB or by using nonimmune IgG. The enrichment of the c-Rel- and CREB-binding site onto the miR-22 promoter in the ChIP product was analyzed by PCR. The PCR products were separated by acrylamide gel electrophoresis. Representative gels are shown in panel A, and densitometry analysis is presented in panel B. (C) HeLa cells were transfected with 3×FLAG-CMV-10-CDK1 or empty vector for 12, 18, and 24 h. Cell lysates were analyzed by Western blotting with indicated antibodies. Protein levels of p-IκBα and p-CREB were quantified by immunoblot scanning using image J software and normalized to the amount of GAPDH. **, P < 0.01.