FIG. 2.
Interaction between RbAp48 and CBP in HeLa cells. (a) GST pull-down assay. A GST fusion protein encoding RbAp48273–425, which contains carboxyl-terminal WD repeats 4 through 7 (GST-RbAp48273–425), and a GST fusion protein containing full-length RbAp48 (GST-RbAp48) were coupled to glutathione-agarose beads and incubated with HeLa cell nuclear extracts. CBP bound to the GST-RbAp48 fusion proteins was visualized by Western blotting. (b) Association of CBP and RbAp48 in vivo. Endogenous RbAp48 was immunoprecipitated from HeLa cell nuclear extracts using a monoclonal antibody against RbAp48. CBP coimmunoprecipitated with RbAp48 and was visualized by Western blotting. Normal mouse immunoglobulin G (IgG) was used as a negative control.