CABIN1 regulates senescence. (A) PD 30 and PD 88 IMR90 fibroblasts stained for markers of senescence, SA β-Gal and SAHF. (B) Cells from panel A were scored for the percentage of cells expressing SA β-Gal, cyclin A, SAHF, HIRA foci, and CABIN1 foci. Values are means ± standard errors of the means (SEM) of three independent experiments. (C) Cells from panel A stained with antibodies to HIRA, PML bodies, and CABIN1 and with DAPI to visualize SAHF. (D) Relative intensity of DAPI, PML body, and CABIN1 fluorescence along a straight line through the CABIN1/PML focus. (E) Western blot showing expression of oncogenic H-RasG12V in IMR90 cells. (F) H-RasG12V-expressing cells stained with antibodies to PML bodies, CABIN1, and with DAPI (4′,6-diamidino-2-phenylindole). (G) IMR90 cells were infected with pLXSN or pLXSN-myc-CABIN1, and lysates were Western blotted with the indicated antibodies. (H) Cells from panel G were scored for SA β-Gal, cyclin A, HIRA foci, and SAHF. Values are means ± SEM of three independent experiments. (I) Cells from panel G stained to detect SA β-Gal and with DAPI to detect SAHF.