Fig. 1
Screening of ATG4B inhibitors based on the approved drugs library by FRET assay. A Illustration of the FRET-based high-throughput screening platform for ATG4B inhibitors. B Scatter plot of inhibition rate of approved library for ATG4B based on FRET assay. Candidate compounds were marked in red. Recombinant ATG4B (0.75 μg/ml) was incubated with 1600 compounds (10 μM) from approved library for 30 min at 37 °C, then FRET substrates (0.75 μg/ml) were added and inhibition rates were determined as indicated. C The inhibitory effect of twenty-four candidate compounds (10 μM) were detected by SDS-PAGE and Coomassie brilliant blue (CBB) staining according to the cleavage of substrates. CON as control without enzymes, NC as negative control without inhibitor, FMK-9a as positive control. D The dose-dependent inhibition of compound 669 (Ebselen) were determined by SDS-PAGE. E IC50 calculation of compound 669 (Ebselen) for ATG4B from fitted curve by FRET assay and its structural formula