Fig. 1

Small molecule S9 binds MDM2 and antagonizes interaction between MDM2 and RPL11. A Structure of compound S9 as for MDM2 inhibitor which was obtained from molecular docking based virtual screening. B Predicted binding mode of MDM2 complexed with compound S9. The protein MDM2 is shown in cartoon mode and colored in blue. S9 is shown in stick mode and colored in green. The key residues for S9 binding were also labeled and colored in yellow. C Addition of 100 μM S9 to U2OS cells followed by western blot detection of thermal stability of MDM2. The line chart beside shows the quantitation results of western blotting images. D U2OS cells were cotransfected with pcDNA3-Flag-MDM2 and pcDNA3-Myc-L11 followed by treatment of S9 for 24 h. Co-IP was performed with anti-Flag antibody followed by immunoblotting with anti-Flag, anti-p53 and anti-Myc antibodies. E U2OS cells were treated with different concentration of S9 for 24 h. Co-IP was performed with homemade anti-MDM2 antibody (2A10) followed by immunoblotting with anti-MDM2, anti-p53 and anti-L11 antibodies