Figure 4.

Interactions of Aurora B with Survivin and CENP-A and its kinase activity are sensitive to RNA depletion. (A) Co-IP experiment using an anti-Aurora B antibody. RNaseA treatment was performed before or after IP of Aurora B. Input lysates (INPUT) and precipitated proteins in the absence of immunoprecipitating antibody (first line) are shown as positive and negative controls, respectively. Co-precipitated Survivin and CENP-A were visualized by western blotting (WB). Asterisk indicates IgG heavy chain which is detected by the secondary antibody. (B) In vitro kinase activity of immunoprecipitated Aurora B from MEL nuclear extracts, treated (+) or not (−) with RNaseA, using core histones as exogenous substrate. Specific histone H3 phosphate incorporation (³²P-H3) was revealed by autoradiography, Aurora B protein levels were determined by western blotting and histones visualized by Ponceau red staining.