Untransfected U2OS cells were lyzed and subjected to immunoprecipitation with control immunoglobulin G (IgG) or anti-XRN2 antibodies. The bound proteins were separated by SDS-PAGE followed by Western blotting with anti-DDX5 or anti-XRN2 antibodies. The migration of DDX5 and XRN2 is depicted with an arrow. 