Partial knockdown of RPS14 leads to binding of RPL11 to HDM2. (A) Western blots showing the increased levels of p53 and RPL11 in A549 cells expressing the indicated shRNAs for 72 hours. Tubulin was used as a loading control. (B) Immunofluorescent images of discrete or disrupted nucleoli in A549 cells expressing the indicated shRNAs or cells treated with 10 ng/mL actinomycin D (Act. D) for 12 hours, respectively. Nucleoli were stained with an antibody against nucleophosmin (B23). Images were visualized with a fluorescent microscope (Olympus IX71) and with the 100× objective lens (Carl Zeiss) and analyzed using IPlab 3.6.5 software. Cells were mounted in Vectashield mounting medium containing 4,6-diamidino-2-phenylindole as counterstain for DNA. Images were visualized with Olympus PLanF1 using 100×/1.30 Oil objective (Carl Zeiss) and captured using SensiCam High Performance camera (The Cooke Corporation). (C) Immunoprecipitation of A549 cell lysates was performed using anti-HDM2 or normal rabbit IgG antibodies. Western blots show the levels of HDM2 and RPL11 in the immunoprecipitates.