Fig. 9: Cell viability and the corresponding degradation of Cofilin-2 upon assembly-directed protein degradation.

a–c Viability of MCF-7 cells treated with different concentrations of (a) BQA-K(Tz)GGGFF for 24 h; (b) TP2T for 24 h; or (c) BQA-K(Tz)GGGFF (100 µM) for 24 h followed by incubation with different concentrations of TP2T for 24 h (n = 3 independent experiments, mean ± SD). d Flow cytometry analysis of cell apoptosis in MCF-7 cells incubated with BQA-K(Tz)GGGFF (100 µM) followed by TP2T (500 nM). e Quantitation of the corresponding apoptosis rate (n = 3 independent experiments, mean ± SD). f Western blot of Cofilin-2 in the hydrogel-based protein pull-down assay. g Fluorescence images of MCF-7 cells treated with or without SA-PROTAC-2 (treatment with BQA-K(Tz)GGGFF (100 µM) for 24 h and then TP2T (50 nM) for 24 h). F-actin was stained with Actin-Tracker Green-488. Scale bar: 10 µm. h, i Western blotting for Cofilin-2 and β-actin showing TP2T concentration-dependent cell-selective downregulation of Cofilin-2 protein levels in (h) MCF-7 cells and (i) HUVECs. j, k Quantitation of the corresponding relative protein expression levels in (j) MCF-7 cells and (k) HUVECs (n = 3 independent experiments, mean ± S.E.M). l Mechanistic investigation of Cofilin-2 degradation. Statistical analysis was performed using a two-tailed Student’s t test with Welch’s correction. The confocal microscopy (g) and immunoblotting experiments (f, i) were repeated three times with similar results. Source data are provided as a Source Data file.