(a) Level of expression of SREBP1 and SREBP2 after rosuvastatin or betulin treatment in Hela cells. Subconfluent cells a fixed with 3.7% paraforldeide after 8 days of rosovastatin (0.1 μM) or betulin (20 μM) treatment and incubated with anti-SREBP1 (1:100, ab28481) or anti SREBP-2 (1 μg/ml ab30682, Abcam) overnight at 4 °C. Then, the cells are incubated with anti-rabbit AlexaFluo488 for 1 h at room temperature. Nuclei are stained with DAPI. Untreated cells are also shown for reference. Images are acquired by Leica SP2 laser scanning confocal microscope. (b) Western blot of SREBP1 and SREBP2 in Hela cells untreated and after 8 days of treatment with (20 μM betulin. 10 μg total protein were loaded on 10% polyacrilamide gel, transferred on PVDF and incubated or anti-SREPB1 (1:500, ab28481, AbCam) or anti-SREBP2 (1:100, ab30682, AbCam) were used overnight at 4 °C. Mouse anti-alpha Tubulin antibody (1:5000, Sigma) for 1 h at room temperature was used as housekeeping. A secondary antibody anti goat-HRP (1:5000, ECL Blotting reagents (GE Healthcare RPN2109)/SuperSignalTM West Femto Maximum Sensitivity Substrate, Thermo scientific) was used for 1 h at room temperature to detect chemiluminiscence. The bands reported are the precursor of SREBP1 and SREBP2, pre-SREBP.