FIG. 1.

Gal-3 expression is repressed in p53-mediated apoptosis. (A) RKO cells were exposed to UV (50 J/m²) and collected 24 h later for cell cycle analysis upon PI staining. DNA-content analysis by flow cytometry of one indicative experiment is reported. (B) Immunoblotting kinetics of p53, PARP-1 and its cleaved form (PARP-1*), and Gal-3 at the indicated times after UV irradiation (50 J/m²). α-Tubulin expression is used as a loading control. (C) Immunoblots with antibody to p53 on RKO cells stably transfected with pSUPER-ctr and pSUPER-p53 vectors. α-Tubulin was used as a loading control. (D) Percentage of dead cells determined by trypan blue exclusion in the indicated cells at the indicated times after UV irradiation. Means ± standard deviations of three independent experiments are reported. (E) Immunoblot of Gal-3 on the indicated cells after UV irradiation. α-Tubulin was used as a loading control. (F) Immunoblot of Gal-3 48 h after UV irradiation of MEF from p53^+/+ and p53^−/− mice. Due to the small amount of apoptosis in these primary cells, the UV-irradiated MEFs were harvested, with the dead, floating cells (f) kept separate from the adherent ones (a). In the case of p53^−/− MEFs, only adherent cells were present. (G) Immunoblotting kinetics of p53 and Gal-3 after infection of p53-null H1299 cells with Adp53 recombinant adenovirus or dl70.3 control virus at an MOI of 50. α-Tubulin was used as a loading control. (H) H1299 cells were infected as described in panel G in the presence of the pan-caspase inhibitor z-VAD or its solvent. Percentage of dead cells was calculated as described for panel D at 24 h postinfection when cells were harvested for immunoblot analyses, as described for panel G. α-tub, α-tubulin.